2007-07-15 05:48:44 +02:00
|
|
|
/* (C) 1999-2001 Paul `Rusty' Russell
|
|
|
|
* (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org>
|
|
|
|
* (C) 2007 Patrick McHardy <kaber@trash.net>
|
|
|
|
*
|
|
|
|
* 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/types.h>
|
|
|
|
#include <linux/timer.h>
|
|
|
|
#include <linux/module.h>
|
|
|
|
#include <linux/udp.h>
|
|
|
|
#include <linux/seq_file.h>
|
|
|
|
#include <linux/skbuff.h>
|
|
|
|
#include <linux/ipv6.h>
|
|
|
|
#include <net/ip6_checksum.h>
|
|
|
|
#include <net/checksum.h>
|
|
|
|
|
|
|
|
#include <linux/netfilter.h>
|
|
|
|
#include <linux/netfilter_ipv4.h>
|
|
|
|
#include <linux/netfilter_ipv6.h>
|
|
|
|
#include <net/netfilter/nf_conntrack_l4proto.h>
|
|
|
|
#include <net/netfilter/nf_conntrack_ecache.h>
|
2007-12-18 07:38:49 +01:00
|
|
|
#include <net/netfilter/nf_log.h>
|
2007-07-15 05:48:44 +02:00
|
|
|
|
|
|
|
static unsigned int nf_ct_udplite_timeout __read_mostly = 30*HZ;
|
|
|
|
static unsigned int nf_ct_udplite_timeout_stream __read_mostly = 180*HZ;
|
|
|
|
|
|
|
|
static int udplite_pkt_to_tuple(const struct sk_buff *skb,
|
|
|
|
unsigned int dataoff,
|
|
|
|
struct nf_conntrack_tuple *tuple)
|
|
|
|
{
|
|
|
|
struct udphdr _hdr, *hp;
|
|
|
|
|
|
|
|
hp = skb_header_pointer(skb, dataoff, sizeof(_hdr), &_hdr);
|
|
|
|
if (hp == NULL)
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
tuple->src.u.udp.port = hp->source;
|
|
|
|
tuple->dst.u.udp.port = hp->dest;
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
|
|
|
|
static int udplite_invert_tuple(struct nf_conntrack_tuple *tuple,
|
|
|
|
const struct nf_conntrack_tuple *orig)
|
|
|
|
{
|
|
|
|
tuple->src.u.udp.port = orig->dst.u.udp.port;
|
|
|
|
tuple->dst.u.udp.port = orig->src.u.udp.port;
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Print out the per-protocol part of the tuple. */
|
|
|
|
static int udplite_print_tuple(struct seq_file *s,
|
|
|
|
const struct nf_conntrack_tuple *tuple)
|
|
|
|
{
|
|
|
|
return seq_printf(s, "sport=%hu dport=%hu ",
|
|
|
|
ntohs(tuple->src.u.udp.port),
|
|
|
|
ntohs(tuple->dst.u.udp.port));
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Returns verdict for packet, and may modify conntracktype */
|
|
|
|
static int udplite_packet(struct nf_conn *conntrack,
|
|
|
|
const struct sk_buff *skb,
|
|
|
|
unsigned int dataoff,
|
|
|
|
enum ip_conntrack_info ctinfo,
|
|
|
|
int pf,
|
|
|
|
unsigned int hooknum)
|
|
|
|
{
|
|
|
|
/* If we've seen traffic both ways, this is some kind of UDP
|
|
|
|
stream. Extend timeout. */
|
|
|
|
if (test_bit(IPS_SEEN_REPLY_BIT, &conntrack->status)) {
|
|
|
|
nf_ct_refresh_acct(conntrack, ctinfo, skb,
|
|
|
|
nf_ct_udplite_timeout_stream);
|
|
|
|
/* Also, more likely to be important, and not a probe */
|
|
|
|
if (!test_and_set_bit(IPS_ASSURED_BIT, &conntrack->status))
|
|
|
|
nf_conntrack_event_cache(IPCT_STATUS, skb);
|
|
|
|
} else
|
|
|
|
nf_ct_refresh_acct(conntrack, ctinfo, skb,
|
|
|
|
nf_ct_udplite_timeout);
|
|
|
|
|
|
|
|
return NF_ACCEPT;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Called when a new connection for this protocol found. */
|
|
|
|
static int udplite_new(struct nf_conn *conntrack, const struct sk_buff *skb,
|
|
|
|
unsigned int dataoff)
|
|
|
|
{
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
|
|
|
|
static int udplite_error(struct sk_buff *skb, unsigned int dataoff,
|
|
|
|
enum ip_conntrack_info *ctinfo,
|
|
|
|
int pf,
|
|
|
|
unsigned int hooknum)
|
|
|
|
{
|
|
|
|
unsigned int udplen = skb->len - dataoff;
|
|
|
|
struct udphdr _hdr, *hdr;
|
|
|
|
unsigned int cscov;
|
|
|
|
|
|
|
|
/* Header is too small? */
|
|
|
|
hdr = skb_header_pointer(skb, dataoff, sizeof(_hdr), &_hdr);
|
|
|
|
if (hdr == NULL) {
|
|
|
|
if (LOG_INVALID(IPPROTO_UDPLITE))
|
|
|
|
nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
|
|
|
|
"nf_ct_udplite: short packet ");
|
|
|
|
return -NF_ACCEPT;
|
|
|
|
}
|
|
|
|
|
|
|
|
cscov = ntohs(hdr->len);
|
|
|
|
if (cscov == 0)
|
|
|
|
cscov = udplen;
|
|
|
|
else if (cscov < sizeof(*hdr) || cscov > udplen) {
|
|
|
|
if (LOG_INVALID(IPPROTO_UDPLITE))
|
|
|
|
nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
|
|
|
|
"nf_ct_udplite: invalid checksum coverage ");
|
|
|
|
return -NF_ACCEPT;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* UDPLITE mandates checksums */
|
|
|
|
if (!hdr->check) {
|
|
|
|
if (LOG_INVALID(IPPROTO_UDPLITE))
|
|
|
|
nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
|
|
|
|
"nf_ct_udplite: checksum missing ");
|
|
|
|
return -NF_ACCEPT;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Checksum invalid? Ignore. */
|
|
|
|
if (nf_conntrack_checksum && !skb_csum_unnecessary(skb) &&
|
2007-11-20 03:53:30 +01:00
|
|
|
hooknum == NF_INET_PRE_ROUTING) {
|
2007-07-15 05:48:44 +02:00
|
|
|
if (pf == PF_INET) {
|
|
|
|
struct iphdr *iph = ip_hdr(skb);
|
|
|
|
|
|
|
|
skb->csum = csum_tcpudp_nofold(iph->saddr, iph->daddr,
|
|
|
|
udplen, IPPROTO_UDPLITE, 0);
|
|
|
|
} else {
|
|
|
|
struct ipv6hdr *ipv6h = ipv6_hdr(skb);
|
|
|
|
__wsum hsum = skb_checksum(skb, 0, dataoff, 0);
|
|
|
|
|
|
|
|
skb->csum = ~csum_unfold(
|
|
|
|
csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr,
|
|
|
|
udplen, IPPROTO_UDPLITE,
|
|
|
|
csum_sub(0, hsum)));
|
|
|
|
}
|
|
|
|
|
|
|
|
skb->ip_summed = CHECKSUM_NONE;
|
|
|
|
if (__skb_checksum_complete_head(skb, dataoff + cscov)) {
|
|
|
|
if (LOG_INVALID(IPPROTO_UDPLITE))
|
|
|
|
nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
|
|
|
|
"nf_ct_udplite: bad UDPLite "
|
|
|
|
"checksum ");
|
|
|
|
return -NF_ACCEPT;
|
|
|
|
}
|
|
|
|
skb->ip_summed = CHECKSUM_UNNECESSARY;
|
|
|
|
}
|
|
|
|
|
|
|
|
return NF_ACCEPT;
|
|
|
|
}
|
|
|
|
|
|
|
|
#ifdef CONFIG_SYSCTL
|
|
|
|
static unsigned int udplite_sysctl_table_users;
|
|
|
|
static struct ctl_table_header *udplite_sysctl_header;
|
|
|
|
static struct ctl_table udplite_sysctl_table[] = {
|
|
|
|
{
|
|
|
|
.ctl_name = CTL_UNNUMBERED,
|
|
|
|
.procname = "nf_conntrack_udplite_timeout",
|
|
|
|
.data = &nf_ct_udplite_timeout,
|
|
|
|
.maxlen = sizeof(unsigned int),
|
|
|
|
.mode = 0644,
|
|
|
|
.proc_handler = &proc_dointvec_jiffies,
|
|
|
|
},
|
|
|
|
{
|
|
|
|
.ctl_name = CTL_UNNUMBERED,
|
|
|
|
.procname = "nf_conntrack_udplite_timeout_stream",
|
|
|
|
.data = &nf_ct_udplite_timeout_stream,
|
|
|
|
.maxlen = sizeof(unsigned int),
|
|
|
|
.mode = 0644,
|
|
|
|
.proc_handler = &proc_dointvec_jiffies,
|
|
|
|
},
|
|
|
|
{
|
|
|
|
.ctl_name = 0
|
|
|
|
}
|
|
|
|
};
|
|
|
|
#endif /* CONFIG_SYSCTL */
|
|
|
|
|
|
|
|
static struct nf_conntrack_l4proto nf_conntrack_l4proto_udplite4 __read_mostly =
|
|
|
|
{
|
|
|
|
.l3proto = PF_INET,
|
|
|
|
.l4proto = IPPROTO_UDPLITE,
|
|
|
|
.name = "udplite",
|
|
|
|
.pkt_to_tuple = udplite_pkt_to_tuple,
|
|
|
|
.invert_tuple = udplite_invert_tuple,
|
|
|
|
.print_tuple = udplite_print_tuple,
|
|
|
|
.packet = udplite_packet,
|
|
|
|
.new = udplite_new,
|
|
|
|
.error = udplite_error,
|
|
|
|
#if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
|
2007-09-28 23:37:41 +02:00
|
|
|
.tuple_to_nlattr = nf_ct_port_tuple_to_nlattr,
|
|
|
|
.nlattr_to_tuple = nf_ct_port_nlattr_to_tuple,
|
2007-09-28 23:39:55 +02:00
|
|
|
.nla_policy = nf_ct_port_nla_policy,
|
2007-07-15 05:48:44 +02:00
|
|
|
#endif
|
|
|
|
#ifdef CONFIG_SYSCTL
|
|
|
|
.ctl_table_users = &udplite_sysctl_table_users,
|
|
|
|
.ctl_table_header = &udplite_sysctl_header,
|
|
|
|
.ctl_table = udplite_sysctl_table,
|
|
|
|
#endif
|
|
|
|
};
|
|
|
|
|
|
|
|
static struct nf_conntrack_l4proto nf_conntrack_l4proto_udplite6 __read_mostly =
|
|
|
|
{
|
|
|
|
.l3proto = PF_INET6,
|
|
|
|
.l4proto = IPPROTO_UDPLITE,
|
|
|
|
.name = "udplite",
|
|
|
|
.pkt_to_tuple = udplite_pkt_to_tuple,
|
|
|
|
.invert_tuple = udplite_invert_tuple,
|
|
|
|
.print_tuple = udplite_print_tuple,
|
|
|
|
.packet = udplite_packet,
|
|
|
|
.new = udplite_new,
|
|
|
|
.error = udplite_error,
|
|
|
|
#if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
|
2007-09-28 23:37:41 +02:00
|
|
|
.tuple_to_nlattr = nf_ct_port_tuple_to_nlattr,
|
|
|
|
.nlattr_to_tuple = nf_ct_port_nlattr_to_tuple,
|
2007-09-28 23:39:55 +02:00
|
|
|
.nla_policy = nf_ct_port_nla_policy,
|
2007-07-15 05:48:44 +02:00
|
|
|
#endif
|
|
|
|
#ifdef CONFIG_SYSCTL
|
|
|
|
.ctl_table_users = &udplite_sysctl_table_users,
|
|
|
|
.ctl_table_header = &udplite_sysctl_header,
|
|
|
|
.ctl_table = udplite_sysctl_table,
|
|
|
|
#endif
|
|
|
|
};
|
|
|
|
|
|
|
|
static int __init nf_conntrack_proto_udplite_init(void)
|
|
|
|
{
|
|
|
|
int err;
|
|
|
|
|
|
|
|
err = nf_conntrack_l4proto_register(&nf_conntrack_l4proto_udplite4);
|
|
|
|
if (err < 0)
|
|
|
|
goto err1;
|
|
|
|
err = nf_conntrack_l4proto_register(&nf_conntrack_l4proto_udplite6);
|
|
|
|
if (err < 0)
|
|
|
|
goto err2;
|
|
|
|
return 0;
|
|
|
|
err2:
|
|
|
|
nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_udplite4);
|
|
|
|
err1:
|
|
|
|
return err;
|
|
|
|
}
|
|
|
|
|
|
|
|
static void __exit nf_conntrack_proto_udplite_exit(void)
|
|
|
|
{
|
|
|
|
nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_udplite6);
|
|
|
|
nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_udplite4);
|
|
|
|
}
|
|
|
|
|
|
|
|
module_init(nf_conntrack_proto_udplite_init);
|
|
|
|
module_exit(nf_conntrack_proto_udplite_exit);
|
|
|
|
|
|
|
|
MODULE_LICENSE("GPL");
|