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/udp.h>
14 #include <linux/seq_file.h>
15 #include <linux/skbuff.h>
16 #include <linux/ipv6.h>
17 #include <net/ip6_checksum.h>
18 #include <net/checksum.h>
20 #include <linux/netfilter.h>
21 #include <linux/netfilter_ipv4.h>
22 #include <linux/netfilter_ipv6.h>
23 #include <net/netfilter/nf_conntrack_l4proto.h>
24 #include <net/netfilter/nf_conntrack_ecache.h>
26 static unsigned int nf_ct_udplite_timeout __read_mostly
= 30*HZ
;
27 static unsigned int nf_ct_udplite_timeout_stream __read_mostly
= 180*HZ
;
29 static int udplite_pkt_to_tuple(const struct sk_buff
*skb
,
31 struct nf_conntrack_tuple
*tuple
)
33 struct udphdr _hdr
, *hp
;
35 hp
= skb_header_pointer(skb
, dataoff
, sizeof(_hdr
), &_hdr
);
39 tuple
->src
.u
.udp
.port
= hp
->source
;
40 tuple
->dst
.u
.udp
.port
= hp
->dest
;
44 static int udplite_invert_tuple(struct nf_conntrack_tuple
*tuple
,
45 const struct nf_conntrack_tuple
*orig
)
47 tuple
->src
.u
.udp
.port
= orig
->dst
.u
.udp
.port
;
48 tuple
->dst
.u
.udp
.port
= orig
->src
.u
.udp
.port
;
52 /* Print out the per-protocol part of the tuple. */
53 static int udplite_print_tuple(struct seq_file
*s
,
54 const struct nf_conntrack_tuple
*tuple
)
56 return seq_printf(s
, "sport=%hu dport=%hu ",
57 ntohs(tuple
->src
.u
.udp
.port
),
58 ntohs(tuple
->dst
.u
.udp
.port
));
61 /* Print out the private part of the conntrack. */
62 static int udplite_print_conntrack(struct seq_file
*s
,
63 const struct nf_conn
*conntrack
)
68 /* Returns verdict for packet, and may modify conntracktype */
69 static int udplite_packet(struct nf_conn
*conntrack
,
70 const struct sk_buff
*skb
,
72 enum ip_conntrack_info ctinfo
,
76 /* If we've seen traffic both ways, this is some kind of UDP
77 stream. Extend timeout. */
78 if (test_bit(IPS_SEEN_REPLY_BIT
, &conntrack
->status
)) {
79 nf_ct_refresh_acct(conntrack
, ctinfo
, skb
,
80 nf_ct_udplite_timeout_stream
);
81 /* Also, more likely to be important, and not a probe */
82 if (!test_and_set_bit(IPS_ASSURED_BIT
, &conntrack
->status
))
83 nf_conntrack_event_cache(IPCT_STATUS
, skb
);
85 nf_ct_refresh_acct(conntrack
, ctinfo
, skb
,
86 nf_ct_udplite_timeout
);
91 /* Called when a new connection for this protocol found. */
92 static int udplite_new(struct nf_conn
*conntrack
, const struct sk_buff
*skb
,
98 static int udplite_error(struct sk_buff
*skb
, unsigned int dataoff
,
99 enum ip_conntrack_info
*ctinfo
,
101 unsigned int hooknum
)
103 unsigned int udplen
= skb
->len
- dataoff
;
104 struct udphdr _hdr
, *hdr
;
107 /* Header is too small? */
108 hdr
= skb_header_pointer(skb
, dataoff
, sizeof(_hdr
), &_hdr
);
110 if (LOG_INVALID(IPPROTO_UDPLITE
))
111 nf_log_packet(pf
, 0, skb
, NULL
, NULL
, NULL
,
112 "nf_ct_udplite: short packet ");
116 cscov
= ntohs(hdr
->len
);
119 else if (cscov
< sizeof(*hdr
) || cscov
> udplen
) {
120 if (LOG_INVALID(IPPROTO_UDPLITE
))
121 nf_log_packet(pf
, 0, skb
, NULL
, NULL
, NULL
,
122 "nf_ct_udplite: invalid checksum coverage ");
126 /* UDPLITE mandates checksums */
128 if (LOG_INVALID(IPPROTO_UDPLITE
))
129 nf_log_packet(pf
, 0, skb
, NULL
, NULL
, NULL
,
130 "nf_ct_udplite: checksum missing ");
134 /* Checksum invalid? Ignore. */
135 if (nf_conntrack_checksum
&& !skb_csum_unnecessary(skb
) &&
136 ((pf
== PF_INET
&& hooknum
== NF_IP_PRE_ROUTING
) ||
137 (pf
== PF_INET6
&& hooknum
== NF_IP6_PRE_ROUTING
))) {
139 struct iphdr
*iph
= ip_hdr(skb
);
141 skb
->csum
= csum_tcpudp_nofold(iph
->saddr
, iph
->daddr
,
142 udplen
, IPPROTO_UDPLITE
, 0);
144 struct ipv6hdr
*ipv6h
= ipv6_hdr(skb
);
145 __wsum hsum
= skb_checksum(skb
, 0, dataoff
, 0);
147 skb
->csum
= ~csum_unfold(
148 csum_ipv6_magic(&ipv6h
->saddr
, &ipv6h
->daddr
,
149 udplen
, IPPROTO_UDPLITE
,
153 skb
->ip_summed
= CHECKSUM_NONE
;
154 if (__skb_checksum_complete_head(skb
, dataoff
+ cscov
)) {
155 if (LOG_INVALID(IPPROTO_UDPLITE
))
156 nf_log_packet(pf
, 0, skb
, NULL
, NULL
, NULL
,
157 "nf_ct_udplite: bad UDPLite "
161 skb
->ip_summed
= CHECKSUM_UNNECESSARY
;
168 static unsigned int udplite_sysctl_table_users
;
169 static struct ctl_table_header
*udplite_sysctl_header
;
170 static struct ctl_table udplite_sysctl_table
[] = {
172 .ctl_name
= CTL_UNNUMBERED
,
173 .procname
= "nf_conntrack_udplite_timeout",
174 .data
= &nf_ct_udplite_timeout
,
175 .maxlen
= sizeof(unsigned int),
177 .proc_handler
= &proc_dointvec_jiffies
,
180 .ctl_name
= CTL_UNNUMBERED
,
181 .procname
= "nf_conntrack_udplite_timeout_stream",
182 .data
= &nf_ct_udplite_timeout_stream
,
183 .maxlen
= sizeof(unsigned int),
185 .proc_handler
= &proc_dointvec_jiffies
,
191 #endif /* CONFIG_SYSCTL */
193 static struct nf_conntrack_l4proto nf_conntrack_l4proto_udplite4 __read_mostly
=
196 .l4proto
= IPPROTO_UDPLITE
,
198 .pkt_to_tuple
= udplite_pkt_to_tuple
,
199 .invert_tuple
= udplite_invert_tuple
,
200 .print_tuple
= udplite_print_tuple
,
201 .print_conntrack
= udplite_print_conntrack
,
202 .packet
= udplite_packet
,
204 .error
= udplite_error
,
205 #if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
206 .tuple_to_nfattr
= nf_ct_port_tuple_to_nfattr
,
207 .nfattr_to_tuple
= nf_ct_port_nfattr_to_tuple
,
210 .ctl_table_users
= &udplite_sysctl_table_users
,
211 .ctl_table_header
= &udplite_sysctl_header
,
212 .ctl_table
= udplite_sysctl_table
,
216 static struct nf_conntrack_l4proto nf_conntrack_l4proto_udplite6 __read_mostly
=
219 .l4proto
= IPPROTO_UDPLITE
,
221 .pkt_to_tuple
= udplite_pkt_to_tuple
,
222 .invert_tuple
= udplite_invert_tuple
,
223 .print_tuple
= udplite_print_tuple
,
224 .print_conntrack
= udplite_print_conntrack
,
225 .packet
= udplite_packet
,
227 .error
= udplite_error
,
228 #if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
229 .tuple_to_nfattr
= nf_ct_port_tuple_to_nfattr
,
230 .nfattr_to_tuple
= nf_ct_port_nfattr_to_tuple
,
233 .ctl_table_users
= &udplite_sysctl_table_users
,
234 .ctl_table_header
= &udplite_sysctl_header
,
235 .ctl_table
= udplite_sysctl_table
,
239 static int __init
nf_conntrack_proto_udplite_init(void)
243 err
= nf_conntrack_l4proto_register(&nf_conntrack_l4proto_udplite4
);
246 err
= nf_conntrack_l4proto_register(&nf_conntrack_l4proto_udplite6
);
251 nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_udplite4
);
256 static void __exit
nf_conntrack_proto_udplite_exit(void)
258 nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_udplite6
);
259 nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_udplite4
);
262 module_init(nf_conntrack_proto_udplite_init
);
263 module_exit(nf_conntrack_proto_udplite_exit
);
265 MODULE_LICENSE("GPL");