1 /* (C) 1999-2001 Paul `Rusty' Russell
2 * (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org>
3 * (C) 2006-2012 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>
25 #include <net/netfilter/nf_log.h>
26 #include <net/netfilter/ipv4/nf_conntrack_ipv4.h>
27 #include <net/netfilter/ipv6/nf_conntrack_ipv6.h>
29 static unsigned int udp_timeouts
[UDP_CT_MAX
] = {
30 [UDP_CT_UNREPLIED
] = 30*HZ
,
31 [UDP_CT_REPLIED
] = 180*HZ
,
34 static inline struct nf_udp_net
*udp_pernet(struct net
*net
)
36 return &net
->ct
.nf_ct_proto
.udp
;
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
)
76 return udp_pernet(net
)->timeouts
;
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(net
, 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(net
, 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(net
, 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
[],
161 struct net
*net
, void *data
)
163 unsigned int *timeouts
= data
;
164 struct nf_udp_net
*un
= udp_pernet(net
);
166 /* set default timeouts for UDP. */
167 timeouts
[UDP_CT_UNREPLIED
] = un
->timeouts
[UDP_CT_UNREPLIED
];
168 timeouts
[UDP_CT_REPLIED
] = un
->timeouts
[UDP_CT_REPLIED
];
170 if (tb
[CTA_TIMEOUT_UDP_UNREPLIED
]) {
171 timeouts
[UDP_CT_UNREPLIED
] =
172 ntohl(nla_get_be32(tb
[CTA_TIMEOUT_UDP_UNREPLIED
])) * HZ
;
174 if (tb
[CTA_TIMEOUT_UDP_REPLIED
]) {
175 timeouts
[UDP_CT_REPLIED
] =
176 ntohl(nla_get_be32(tb
[CTA_TIMEOUT_UDP_REPLIED
])) * HZ
;
182 udp_timeout_obj_to_nlattr(struct sk_buff
*skb
, const void *data
)
184 const unsigned int *timeouts
= data
;
186 if (nla_put_be32(skb
, CTA_TIMEOUT_UDP_UNREPLIED
,
187 htonl(timeouts
[UDP_CT_UNREPLIED
] / HZ
)) ||
188 nla_put_be32(skb
, CTA_TIMEOUT_UDP_REPLIED
,
189 htonl(timeouts
[UDP_CT_REPLIED
] / HZ
)))
190 goto nla_put_failure
;
197 static const struct nla_policy
198 udp_timeout_nla_policy
[CTA_TIMEOUT_UDP_MAX
+1] = {
199 [CTA_TIMEOUT_UDP_UNREPLIED
] = { .type
= NLA_U32
},
200 [CTA_TIMEOUT_UDP_REPLIED
] = { .type
= NLA_U32
},
202 #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
205 static struct ctl_table udp_sysctl_table
[] = {
207 .procname
= "nf_conntrack_udp_timeout",
208 .maxlen
= sizeof(unsigned int),
210 .proc_handler
= proc_dointvec_jiffies
,
213 .procname
= "nf_conntrack_udp_timeout_stream",
214 .maxlen
= sizeof(unsigned int),
216 .proc_handler
= proc_dointvec_jiffies
,
220 #ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT
221 static struct ctl_table udp_compat_sysctl_table
[] = {
223 .procname
= "ip_conntrack_udp_timeout",
224 .maxlen
= sizeof(unsigned int),
226 .proc_handler
= proc_dointvec_jiffies
,
229 .procname
= "ip_conntrack_udp_timeout_stream",
230 .maxlen
= sizeof(unsigned int),
232 .proc_handler
= proc_dointvec_jiffies
,
236 #endif /* CONFIG_NF_CONNTRACK_PROC_COMPAT */
237 #endif /* CONFIG_SYSCTL */
239 static int udp_kmemdup_sysctl_table(struct nf_proto_net
*pn
,
240 struct nf_udp_net
*un
)
245 pn
->ctl_table
= kmemdup(udp_sysctl_table
,
246 sizeof(udp_sysctl_table
),
250 pn
->ctl_table
[0].data
= &un
->timeouts
[UDP_CT_UNREPLIED
];
251 pn
->ctl_table
[1].data
= &un
->timeouts
[UDP_CT_REPLIED
];
256 static int udp_kmemdup_compat_sysctl_table(struct nf_proto_net
*pn
,
257 struct nf_udp_net
*un
)
260 #ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT
261 pn
->ctl_compat_table
= kmemdup(udp_compat_sysctl_table
,
262 sizeof(udp_compat_sysctl_table
),
264 if (!pn
->ctl_compat_table
)
267 pn
->ctl_compat_table
[0].data
= &un
->timeouts
[UDP_CT_UNREPLIED
];
268 pn
->ctl_compat_table
[1].data
= &un
->timeouts
[UDP_CT_REPLIED
];
274 static int udp_init_net(struct net
*net
, u_int16_t proto
)
277 struct nf_udp_net
*un
= udp_pernet(net
);
278 struct nf_proto_net
*pn
= &un
->pn
;
283 for (i
= 0; i
< UDP_CT_MAX
; i
++)
284 un
->timeouts
[i
] = udp_timeouts
[i
];
287 if (proto
== AF_INET
) {
288 ret
= udp_kmemdup_compat_sysctl_table(pn
, un
);
292 ret
= udp_kmemdup_sysctl_table(pn
, un
);
294 nf_ct_kfree_compat_sysctl_table(pn
);
296 ret
= udp_kmemdup_sysctl_table(pn
, un
);
301 static struct nf_proto_net
*udp_get_net_proto(struct net
*net
)
303 return &net
->ct
.nf_ct_proto
.udp
.pn
;
306 struct nf_conntrack_l4proto nf_conntrack_l4proto_udp4 __read_mostly
=
309 .l4proto
= IPPROTO_UDP
,
311 .pkt_to_tuple
= udp_pkt_to_tuple
,
312 .invert_tuple
= udp_invert_tuple
,
313 .print_tuple
= udp_print_tuple
,
314 .packet
= udp_packet
,
315 .get_timeouts
= udp_get_timeouts
,
318 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
319 .tuple_to_nlattr
= nf_ct_port_tuple_to_nlattr
,
320 .nlattr_to_tuple
= nf_ct_port_nlattr_to_tuple
,
321 .nlattr_tuple_size
= nf_ct_port_nlattr_tuple_size
,
322 .nla_policy
= nf_ct_port_nla_policy
,
324 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
326 .nlattr_to_obj
= udp_timeout_nlattr_to_obj
,
327 .obj_to_nlattr
= udp_timeout_obj_to_nlattr
,
328 .nlattr_max
= CTA_TIMEOUT_UDP_MAX
,
329 .obj_size
= sizeof(unsigned int) * CTA_TIMEOUT_UDP_MAX
,
330 .nla_policy
= udp_timeout_nla_policy
,
332 #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
333 .init_net
= udp_init_net
,
334 .get_net_proto
= udp_get_net_proto
,
336 EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_udp4
);
338 struct nf_conntrack_l4proto nf_conntrack_l4proto_udp6 __read_mostly
=
341 .l4proto
= IPPROTO_UDP
,
343 .pkt_to_tuple
= udp_pkt_to_tuple
,
344 .invert_tuple
= udp_invert_tuple
,
345 .print_tuple
= udp_print_tuple
,
346 .packet
= udp_packet
,
347 .get_timeouts
= udp_get_timeouts
,
350 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
351 .tuple_to_nlattr
= nf_ct_port_tuple_to_nlattr
,
352 .nlattr_to_tuple
= nf_ct_port_nlattr_to_tuple
,
353 .nlattr_tuple_size
= nf_ct_port_nlattr_tuple_size
,
354 .nla_policy
= nf_ct_port_nla_policy
,
356 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
358 .nlattr_to_obj
= udp_timeout_nlattr_to_obj
,
359 .obj_to_nlattr
= udp_timeout_obj_to_nlattr
,
360 .nlattr_max
= CTA_TIMEOUT_UDP_MAX
,
361 .obj_size
= sizeof(unsigned int) * CTA_TIMEOUT_UDP_MAX
,
362 .nla_policy
= udp_timeout_nla_policy
,
364 #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
365 .init_net
= udp_init_net
,
366 .get_net_proto
= udp_get_net_proto
,
368 EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_udp6
);