1 /* (C) 1999-2001 Paul `Rusty' Russell
2 * (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org>
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
9 #include <linux/types.h>
10 #include <linux/timer.h>
11 #include <linux/module.h>
12 #include <linux/udp.h>
13 #include <linux/seq_file.h>
14 #include <linux/skbuff.h>
15 #include <linux/ipv6.h>
16 #include <net/ip6_checksum.h>
17 #include <net/checksum.h>
19 #include <linux/netfilter.h>
20 #include <linux/netfilter_ipv4.h>
21 #include <linux/netfilter_ipv6.h>
22 #include <net/netfilter/nf_conntrack_l4proto.h>
23 #include <net/netfilter/nf_conntrack_ecache.h>
24 #include <net/netfilter/nf_log.h>
25 #include <net/netfilter/ipv4/nf_conntrack_ipv4.h>
26 #include <net/netfilter/ipv6/nf_conntrack_ipv6.h>
34 static unsigned int udp_timeouts
[UDP_CT_MAX
] = {
35 [UDP_CT_UNREPLIED
] = 30*HZ
,
36 [UDP_CT_REPLIED
] = 180*HZ
,
39 static bool udp_pkt_to_tuple(const struct sk_buff
*skb
,
41 struct nf_conntrack_tuple
*tuple
)
43 const struct udphdr
*hp
;
46 /* Actually only need first 8 bytes. */
47 hp
= skb_header_pointer(skb
, dataoff
, sizeof(_hdr
), &_hdr
);
51 tuple
->src
.u
.udp
.port
= hp
->source
;
52 tuple
->dst
.u
.udp
.port
= hp
->dest
;
57 static bool udp_invert_tuple(struct nf_conntrack_tuple
*tuple
,
58 const struct nf_conntrack_tuple
*orig
)
60 tuple
->src
.u
.udp
.port
= orig
->dst
.u
.udp
.port
;
61 tuple
->dst
.u
.udp
.port
= orig
->src
.u
.udp
.port
;
65 /* Print out the per-protocol part of the tuple. */
66 static int udp_print_tuple(struct seq_file
*s
,
67 const struct nf_conntrack_tuple
*tuple
)
69 return seq_printf(s
, "sport=%hu dport=%hu ",
70 ntohs(tuple
->src
.u
.udp
.port
),
71 ntohs(tuple
->dst
.u
.udp
.port
));
74 static unsigned int *udp_get_timeouts(struct net
*net
)
79 /* Returns verdict for packet, and may modify conntracktype */
80 static int udp_packet(struct nf_conn
*ct
,
81 const struct sk_buff
*skb
,
83 enum ip_conntrack_info ctinfo
,
86 unsigned int *timeouts
)
88 /* If we've seen traffic both ways, this is some kind of UDP
89 stream. Extend timeout. */
90 if (test_bit(IPS_SEEN_REPLY_BIT
, &ct
->status
)) {
91 nf_ct_refresh_acct(ct
, ctinfo
, skb
,
92 timeouts
[UDP_CT_REPLIED
]);
93 /* Also, more likely to be important, and not a probe */
94 if (!test_and_set_bit(IPS_ASSURED_BIT
, &ct
->status
))
95 nf_conntrack_event_cache(IPCT_ASSURED
, ct
);
97 nf_ct_refresh_acct(ct
, ctinfo
, skb
,
98 timeouts
[UDP_CT_UNREPLIED
]);
103 /* Called when a new connection for this protocol found. */
104 static bool udp_new(struct nf_conn
*ct
, const struct sk_buff
*skb
,
105 unsigned int dataoff
, unsigned int *timeouts
)
110 static int udp_error(struct net
*net
, struct nf_conn
*tmpl
, struct sk_buff
*skb
,
111 unsigned int dataoff
, enum ip_conntrack_info
*ctinfo
,
113 unsigned int hooknum
)
115 unsigned int udplen
= skb
->len
- dataoff
;
116 const struct udphdr
*hdr
;
119 /* Header is too small? */
120 hdr
= skb_header_pointer(skb
, dataoff
, sizeof(_hdr
), &_hdr
);
122 if (LOG_INVALID(net
, IPPROTO_UDP
))
123 nf_log_packet(pf
, 0, skb
, NULL
, NULL
, NULL
,
124 "nf_ct_udp: short packet ");
128 /* Truncated/malformed packets */
129 if (ntohs(hdr
->len
) > udplen
|| ntohs(hdr
->len
) < sizeof(*hdr
)) {
130 if (LOG_INVALID(net
, IPPROTO_UDP
))
131 nf_log_packet(pf
, 0, skb
, NULL
, NULL
, NULL
,
132 "nf_ct_udp: truncated/malformed packet ");
136 /* Packet with no checksum */
140 /* Checksum invalid? Ignore.
141 * We skip checking packets on the outgoing path
142 * because the checksum is assumed to be correct.
143 * FIXME: Source route IP option packets --RR */
144 if (net
->ct
.sysctl_checksum
&& hooknum
== NF_INET_PRE_ROUTING
&&
145 nf_checksum(skb
, hooknum
, dataoff
, IPPROTO_UDP
, pf
)) {
146 if (LOG_INVALID(net
, IPPROTO_UDP
))
147 nf_log_packet(pf
, 0, skb
, NULL
, NULL
, NULL
,
148 "nf_ct_udp: bad UDP checksum ");
155 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
157 #include <linux/netfilter/nfnetlink.h>
158 #include <linux/netfilter/nfnetlink_cttimeout.h>
160 static int udp_timeout_nlattr_to_obj(struct nlattr
*tb
[], void *data
)
162 unsigned int *timeouts
= data
;
164 /* set default timeouts for UDP. */
165 timeouts
[UDP_CT_UNREPLIED
] = udp_timeouts
[UDP_CT_UNREPLIED
];
166 timeouts
[UDP_CT_REPLIED
] = udp_timeouts
[UDP_CT_REPLIED
];
168 if (tb
[CTA_TIMEOUT_UDP_UNREPLIED
]) {
169 timeouts
[UDP_CT_UNREPLIED
] =
170 ntohl(nla_get_be32(tb
[CTA_TIMEOUT_UDP_UNREPLIED
])) * HZ
;
172 if (tb
[CTA_TIMEOUT_UDP_REPLIED
]) {
173 timeouts
[UDP_CT_REPLIED
] =
174 ntohl(nla_get_be32(tb
[CTA_TIMEOUT_UDP_REPLIED
])) * HZ
;
180 udp_timeout_obj_to_nlattr(struct sk_buff
*skb
, const void *data
)
182 const unsigned int *timeouts
= data
;
184 if (nla_put_be32(skb
, CTA_TIMEOUT_UDP_UNREPLIED
,
185 htonl(timeouts
[UDP_CT_UNREPLIED
] / HZ
)) ||
186 nla_put_be32(skb
, CTA_TIMEOUT_UDP_REPLIED
,
187 htonl(timeouts
[UDP_CT_REPLIED
] / HZ
)))
188 goto nla_put_failure
;
195 static const struct nla_policy
196 udp_timeout_nla_policy
[CTA_TIMEOUT_UDP_MAX
+1] = {
197 [CTA_TIMEOUT_UDP_UNREPLIED
] = { .type
= NLA_U32
},
198 [CTA_TIMEOUT_UDP_REPLIED
] = { .type
= NLA_U32
},
200 #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
203 static unsigned int udp_sysctl_table_users
;
204 static struct ctl_table_header
*udp_sysctl_header
;
205 static struct ctl_table udp_sysctl_table
[] = {
207 .procname
= "nf_conntrack_udp_timeout",
208 .data
= &udp_timeouts
[UDP_CT_UNREPLIED
],
209 .maxlen
= sizeof(unsigned int),
211 .proc_handler
= proc_dointvec_jiffies
,
214 .procname
= "nf_conntrack_udp_timeout_stream",
215 .data
= &udp_timeouts
[UDP_CT_REPLIED
],
216 .maxlen
= sizeof(unsigned int),
218 .proc_handler
= proc_dointvec_jiffies
,
222 #ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT
223 static struct ctl_table udp_compat_sysctl_table
[] = {
225 .procname
= "ip_conntrack_udp_timeout",
226 .data
= &udp_timeouts
[UDP_CT_UNREPLIED
],
227 .maxlen
= sizeof(unsigned int),
229 .proc_handler
= proc_dointvec_jiffies
,
232 .procname
= "ip_conntrack_udp_timeout_stream",
233 .data
= &udp_timeouts
[UDP_CT_REPLIED
],
234 .maxlen
= sizeof(unsigned int),
236 .proc_handler
= proc_dointvec_jiffies
,
240 #endif /* CONFIG_NF_CONNTRACK_PROC_COMPAT */
241 #endif /* CONFIG_SYSCTL */
243 struct nf_conntrack_l4proto nf_conntrack_l4proto_udp4 __read_mostly
=
246 .l4proto
= IPPROTO_UDP
,
248 .pkt_to_tuple
= udp_pkt_to_tuple
,
249 .invert_tuple
= udp_invert_tuple
,
250 .print_tuple
= udp_print_tuple
,
251 .packet
= udp_packet
,
252 .get_timeouts
= udp_get_timeouts
,
255 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
256 .tuple_to_nlattr
= nf_ct_port_tuple_to_nlattr
,
257 .nlattr_to_tuple
= nf_ct_port_nlattr_to_tuple
,
258 .nlattr_tuple_size
= nf_ct_port_nlattr_tuple_size
,
259 .nla_policy
= nf_ct_port_nla_policy
,
261 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
263 .nlattr_to_obj
= udp_timeout_nlattr_to_obj
,
264 .obj_to_nlattr
= udp_timeout_obj_to_nlattr
,
265 .nlattr_max
= CTA_TIMEOUT_UDP_MAX
,
266 .obj_size
= sizeof(unsigned int) * CTA_TIMEOUT_UDP_MAX
,
267 .nla_policy
= udp_timeout_nla_policy
,
269 #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
271 .ctl_table_users
= &udp_sysctl_table_users
,
272 .ctl_table_header
= &udp_sysctl_header
,
273 .ctl_table
= udp_sysctl_table
,
274 #ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT
275 .ctl_compat_table
= udp_compat_sysctl_table
,
279 EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_udp4
);
281 struct nf_conntrack_l4proto nf_conntrack_l4proto_udp6 __read_mostly
=
284 .l4proto
= IPPROTO_UDP
,
286 .pkt_to_tuple
= udp_pkt_to_tuple
,
287 .invert_tuple
= udp_invert_tuple
,
288 .print_tuple
= udp_print_tuple
,
289 .packet
= udp_packet
,
290 .get_timeouts
= udp_get_timeouts
,
293 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
294 .tuple_to_nlattr
= nf_ct_port_tuple_to_nlattr
,
295 .nlattr_to_tuple
= nf_ct_port_nlattr_to_tuple
,
296 .nlattr_tuple_size
= nf_ct_port_nlattr_tuple_size
,
297 .nla_policy
= nf_ct_port_nla_policy
,
299 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
301 .nlattr_to_obj
= udp_timeout_nlattr_to_obj
,
302 .obj_to_nlattr
= udp_timeout_obj_to_nlattr
,
303 .nlattr_max
= CTA_TIMEOUT_UDP_MAX
,
304 .obj_size
= sizeof(unsigned int) * CTA_TIMEOUT_UDP_MAX
,
305 .nla_policy
= udp_timeout_nla_policy
,
307 #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
309 .ctl_table_users
= &udp_sysctl_table_users
,
310 .ctl_table_header
= &udp_sysctl_header
,
311 .ctl_table
= udp_sysctl_table
,
314 EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_udp6
);