1 /* (C) 1999-2001 Paul `Rusty' Russell
2 * (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org>
3 * (C) 2007 Patrick McHardy <kaber@trash.net>
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
10 #include <linux/types.h>
11 #include <linux/timer.h>
12 #include <linux/module.h>
13 #include <linux/netfilter.h>
14 #include <linux/udp.h>
15 #include <linux/seq_file.h>
16 #include <linux/skbuff.h>
17 #include <linux/ipv6.h>
18 #include <net/ip6_checksum.h>
19 #include <net/checksum.h>
21 #include <linux/netfilter.h>
22 #include <linux/netfilter_ipv4.h>
23 #include <linux/netfilter_ipv6.h>
24 #include <net/netfilter/nf_conntrack_l4proto.h>
25 #include <net/netfilter/nf_conntrack_ecache.h>
27 static unsigned int nf_ct_udplite_timeout __read_mostly
= 30*HZ
;
28 static unsigned int nf_ct_udplite_timeout_stream __read_mostly
= 180*HZ
;
30 static int udplite_pkt_to_tuple(const struct sk_buff
*skb
,
32 struct nf_conntrack_tuple
*tuple
)
34 struct udphdr _hdr
, *hp
;
36 hp
= skb_header_pointer(skb
, dataoff
, sizeof(_hdr
), &_hdr
);
40 tuple
->src
.u
.udp
.port
= hp
->source
;
41 tuple
->dst
.u
.udp
.port
= hp
->dest
;
45 static int udplite_invert_tuple(struct nf_conntrack_tuple
*tuple
,
46 const struct nf_conntrack_tuple
*orig
)
48 tuple
->src
.u
.udp
.port
= orig
->dst
.u
.udp
.port
;
49 tuple
->dst
.u
.udp
.port
= orig
->src
.u
.udp
.port
;
53 /* Print out the per-protocol part of the tuple. */
54 static int udplite_print_tuple(struct seq_file
*s
,
55 const struct nf_conntrack_tuple
*tuple
)
57 return seq_printf(s
, "sport=%hu dport=%hu ",
58 ntohs(tuple
->src
.u
.udp
.port
),
59 ntohs(tuple
->dst
.u
.udp
.port
));
62 /* Print out the private part of the conntrack. */
63 static int udplite_print_conntrack(struct seq_file
*s
,
64 const struct nf_conn
*conntrack
)
69 /* Returns verdict for packet, and may modify conntracktype */
70 static int udplite_packet(struct nf_conn
*conntrack
,
71 const struct sk_buff
*skb
,
73 enum ip_conntrack_info ctinfo
,
77 /* If we've seen traffic both ways, this is some kind of UDP
78 stream. Extend timeout. */
79 if (test_bit(IPS_SEEN_REPLY_BIT
, &conntrack
->status
)) {
80 nf_ct_refresh_acct(conntrack
, ctinfo
, skb
,
81 nf_ct_udplite_timeout_stream
);
82 /* Also, more likely to be important, and not a probe */
83 if (!test_and_set_bit(IPS_ASSURED_BIT
, &conntrack
->status
))
84 nf_conntrack_event_cache(IPCT_STATUS
, skb
);
86 nf_ct_refresh_acct(conntrack
, ctinfo
, skb
,
87 nf_ct_udplite_timeout
);
92 /* Called when a new connection for this protocol found. */
93 static int udplite_new(struct nf_conn
*conntrack
, const struct sk_buff
*skb
,
99 static int udplite_error(struct sk_buff
*skb
, unsigned int dataoff
,
100 enum ip_conntrack_info
*ctinfo
,
102 unsigned int hooknum
)
104 unsigned int udplen
= skb
->len
- dataoff
;
105 struct udphdr _hdr
, *hdr
;
108 /* Header is too small? */
109 hdr
= skb_header_pointer(skb
, dataoff
, sizeof(_hdr
), &_hdr
);
111 if (LOG_INVALID(IPPROTO_UDPLITE
))
112 nf_log_packet(pf
, 0, skb
, NULL
, NULL
, NULL
,
113 "nf_ct_udplite: short packet ");
117 cscov
= ntohs(hdr
->len
);
120 else if (cscov
< sizeof(*hdr
) || cscov
> udplen
) {
121 if (LOG_INVALID(IPPROTO_UDPLITE
))
122 nf_log_packet(pf
, 0, skb
, NULL
, NULL
, NULL
,
123 "nf_ct_udplite: invalid checksum coverage ");
127 /* UDPLITE mandates checksums */
129 if (LOG_INVALID(IPPROTO_UDPLITE
))
130 nf_log_packet(pf
, 0, skb
, NULL
, NULL
, NULL
,
131 "nf_ct_udplite: checksum missing ");
135 /* Checksum invalid? Ignore. */
136 if (nf_conntrack_checksum
&& !skb_csum_unnecessary(skb
) &&
137 ((pf
== PF_INET
&& hooknum
== NF_IP_PRE_ROUTING
) ||
138 (pf
== PF_INET6
&& hooknum
== NF_IP6_PRE_ROUTING
))) {
140 struct iphdr
*iph
= ip_hdr(skb
);
142 skb
->csum
= csum_tcpudp_nofold(iph
->saddr
, iph
->daddr
,
143 udplen
, IPPROTO_UDPLITE
, 0);
145 struct ipv6hdr
*ipv6h
= ipv6_hdr(skb
);
146 __wsum hsum
= skb_checksum(skb
, 0, dataoff
, 0);
148 skb
->csum
= ~csum_unfold(
149 csum_ipv6_magic(&ipv6h
->saddr
, &ipv6h
->daddr
,
150 udplen
, IPPROTO_UDPLITE
,
154 skb
->ip_summed
= CHECKSUM_NONE
;
155 if (__skb_checksum_complete_head(skb
, dataoff
+ cscov
)) {
156 if (LOG_INVALID(IPPROTO_UDPLITE
))
157 nf_log_packet(pf
, 0, skb
, NULL
, NULL
, NULL
,
158 "nf_ct_udplite: bad UDPLite "
162 skb
->ip_summed
= CHECKSUM_UNNECESSARY
;
169 static unsigned int udplite_sysctl_table_users
;
170 static struct ctl_table_header
*udplite_sysctl_header
;
171 static struct ctl_table udplite_sysctl_table
[] = {
173 .ctl_name
= CTL_UNNUMBERED
,
174 .procname
= "nf_conntrack_udplite_timeout",
175 .data
= &nf_ct_udplite_timeout
,
176 .maxlen
= sizeof(unsigned int),
178 .proc_handler
= &proc_dointvec_jiffies
,
181 .ctl_name
= CTL_UNNUMBERED
,
182 .procname
= "nf_conntrack_udplite_timeout_stream",
183 .data
= &nf_ct_udplite_timeout_stream
,
184 .maxlen
= sizeof(unsigned int),
186 .proc_handler
= &proc_dointvec_jiffies
,
192 #endif /* CONFIG_SYSCTL */
194 static struct nf_conntrack_l4proto nf_conntrack_l4proto_udplite4 __read_mostly
=
197 .l4proto
= IPPROTO_UDPLITE
,
199 .pkt_to_tuple
= udplite_pkt_to_tuple
,
200 .invert_tuple
= udplite_invert_tuple
,
201 .print_tuple
= udplite_print_tuple
,
202 .print_conntrack
= udplite_print_conntrack
,
203 .packet
= udplite_packet
,
205 .error
= udplite_error
,
206 #if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
207 .tuple_to_nfattr
= nf_ct_port_tuple_to_nfattr
,
208 .nfattr_to_tuple
= nf_ct_port_nfattr_to_tuple
,
211 .ctl_table_users
= &udplite_sysctl_table_users
,
212 .ctl_table_header
= &udplite_sysctl_header
,
213 .ctl_table
= udplite_sysctl_table
,
217 static struct nf_conntrack_l4proto nf_conntrack_l4proto_udplite6 __read_mostly
=
220 .l4proto
= IPPROTO_UDPLITE
,
222 .pkt_to_tuple
= udplite_pkt_to_tuple
,
223 .invert_tuple
= udplite_invert_tuple
,
224 .print_tuple
= udplite_print_tuple
,
225 .print_conntrack
= udplite_print_conntrack
,
226 .packet
= udplite_packet
,
228 .error
= udplite_error
,
229 #if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
230 .tuple_to_nfattr
= nf_ct_port_tuple_to_nfattr
,
231 .nfattr_to_tuple
= nf_ct_port_nfattr_to_tuple
,
234 .ctl_table_users
= &udplite_sysctl_table_users
,
235 .ctl_table_header
= &udplite_sysctl_header
,
236 .ctl_table
= udplite_sysctl_table
,
240 static int __init
nf_conntrack_proto_udplite_init(void)
244 err
= nf_conntrack_l4proto_register(&nf_conntrack_l4proto_udplite4
);
247 err
= nf_conntrack_l4proto_register(&nf_conntrack_l4proto_udplite6
);
252 nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_udplite4
);
257 static void __exit
nf_conntrack_proto_udplite_exit(void)
259 nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_udplite6
);
260 nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_udplite4
);
263 module_init(nf_conntrack_proto_udplite_init
);
264 module_exit(nf_conntrack_proto_udplite_exit
);
266 MODULE_LICENSE("GPL");