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_conntrack_timeout.h>
26 #include <net/netfilter/nf_log.h>
27 #include <net/netfilter/ipv4/nf_conntrack_ipv4.h>
28 #include <net/netfilter/ipv6/nf_conntrack_ipv6.h>
30 static const unsigned int udp_timeouts
[UDP_CT_MAX
] = {
31 [UDP_CT_UNREPLIED
] = 30*HZ
,
32 [UDP_CT_REPLIED
] = 180*HZ
,
35 static inline struct nf_udp_net
*udp_pernet(struct net
*net
)
37 return &net
->ct
.nf_ct_proto
.udp
;
40 static unsigned int *udp_get_timeouts(struct net
*net
)
42 return udp_pernet(net
)->timeouts
;
45 /* Returns verdict for packet, and may modify conntracktype */
46 static int udp_packet(struct nf_conn
*ct
,
47 const struct sk_buff
*skb
,
49 enum ip_conntrack_info ctinfo
)
51 unsigned int *timeouts
;
53 timeouts
= nf_ct_timeout_lookup(ct
);
55 timeouts
= udp_get_timeouts(nf_ct_net(ct
));
57 /* If we've seen traffic both ways, this is some kind of UDP
58 stream. Extend timeout. */
59 if (test_bit(IPS_SEEN_REPLY_BIT
, &ct
->status
)) {
60 nf_ct_refresh_acct(ct
, ctinfo
, skb
,
61 timeouts
[UDP_CT_REPLIED
]);
62 /* Also, more likely to be important, and not a probe */
63 if (!test_and_set_bit(IPS_ASSURED_BIT
, &ct
->status
))
64 nf_conntrack_event_cache(IPCT_ASSURED
, ct
);
66 nf_ct_refresh_acct(ct
, ctinfo
, skb
,
67 timeouts
[UDP_CT_UNREPLIED
]);
72 /* Called when a new connection for this protocol found. */
73 static bool udp_new(struct nf_conn
*ct
, const struct sk_buff
*skb
,
79 #ifdef CONFIG_NF_CT_PROTO_UDPLITE
80 static void udplite_error_log(const struct sk_buff
*skb
, struct net
*net
,
81 u8 pf
, const char *msg
)
83 nf_l4proto_log_invalid(skb
, net
, pf
, IPPROTO_UDPLITE
, "%s", msg
);
86 static int udplite_error(struct net
*net
, struct nf_conn
*tmpl
,
89 u8 pf
, unsigned int hooknum
)
91 unsigned int udplen
= skb
->len
- dataoff
;
92 const struct udphdr
*hdr
;
96 /* Header is too small? */
97 hdr
= skb_header_pointer(skb
, dataoff
, sizeof(_hdr
), &_hdr
);
99 udplite_error_log(skb
, net
, pf
, "short packet");
103 cscov
= ntohs(hdr
->len
);
106 } else if (cscov
< sizeof(*hdr
) || cscov
> udplen
) {
107 udplite_error_log(skb
, net
, pf
, "invalid checksum coverage");
111 /* UDPLITE mandates checksums */
113 udplite_error_log(skb
, net
, pf
, "checksum missing");
117 /* Checksum invalid? Ignore. */
118 if (net
->ct
.sysctl_checksum
&& hooknum
== NF_INET_PRE_ROUTING
&&
119 nf_checksum_partial(skb
, hooknum
, dataoff
, cscov
, IPPROTO_UDP
,
121 udplite_error_log(skb
, net
, pf
, "bad checksum");
129 static void udp_error_log(const struct sk_buff
*skb
, struct net
*net
,
130 u8 pf
, const char *msg
)
132 nf_l4proto_log_invalid(skb
, net
, pf
, IPPROTO_UDP
, "%s", msg
);
135 static int udp_error(struct net
*net
, struct nf_conn
*tmpl
, struct sk_buff
*skb
,
136 unsigned int dataoff
,
138 unsigned int hooknum
)
140 unsigned int udplen
= skb
->len
- dataoff
;
141 const struct udphdr
*hdr
;
144 /* Header is too small? */
145 hdr
= skb_header_pointer(skb
, dataoff
, sizeof(_hdr
), &_hdr
);
147 udp_error_log(skb
, net
, pf
, "short packet");
151 /* Truncated/malformed packets */
152 if (ntohs(hdr
->len
) > udplen
|| ntohs(hdr
->len
) < sizeof(*hdr
)) {
153 udp_error_log(skb
, net
, pf
, "truncated/malformed packet");
157 /* Packet with no checksum */
161 /* Checksum invalid? Ignore.
162 * We skip checking packets on the outgoing path
163 * because the checksum is assumed to be correct.
164 * FIXME: Source route IP option packets --RR */
165 if (net
->ct
.sysctl_checksum
&& hooknum
== NF_INET_PRE_ROUTING
&&
166 nf_checksum(skb
, hooknum
, dataoff
, IPPROTO_UDP
, pf
)) {
167 udp_error_log(skb
, net
, pf
, "bad checksum");
174 #ifdef CONFIG_NF_CONNTRACK_TIMEOUT
176 #include <linux/netfilter/nfnetlink.h>
177 #include <linux/netfilter/nfnetlink_cttimeout.h>
179 static int udp_timeout_nlattr_to_obj(struct nlattr
*tb
[],
180 struct net
*net
, void *data
)
182 unsigned int *timeouts
= data
;
183 struct nf_udp_net
*un
= udp_pernet(net
);
186 timeouts
= un
->timeouts
;
188 /* set default timeouts for UDP. */
189 timeouts
[UDP_CT_UNREPLIED
] = un
->timeouts
[UDP_CT_UNREPLIED
];
190 timeouts
[UDP_CT_REPLIED
] = un
->timeouts
[UDP_CT_REPLIED
];
192 if (tb
[CTA_TIMEOUT_UDP_UNREPLIED
]) {
193 timeouts
[UDP_CT_UNREPLIED
] =
194 ntohl(nla_get_be32(tb
[CTA_TIMEOUT_UDP_UNREPLIED
])) * HZ
;
196 if (tb
[CTA_TIMEOUT_UDP_REPLIED
]) {
197 timeouts
[UDP_CT_REPLIED
] =
198 ntohl(nla_get_be32(tb
[CTA_TIMEOUT_UDP_REPLIED
])) * HZ
;
204 udp_timeout_obj_to_nlattr(struct sk_buff
*skb
, const void *data
)
206 const unsigned int *timeouts
= data
;
208 if (nla_put_be32(skb
, CTA_TIMEOUT_UDP_UNREPLIED
,
209 htonl(timeouts
[UDP_CT_UNREPLIED
] / HZ
)) ||
210 nla_put_be32(skb
, CTA_TIMEOUT_UDP_REPLIED
,
211 htonl(timeouts
[UDP_CT_REPLIED
] / HZ
)))
212 goto nla_put_failure
;
219 static const struct nla_policy
220 udp_timeout_nla_policy
[CTA_TIMEOUT_UDP_MAX
+1] = {
221 [CTA_TIMEOUT_UDP_UNREPLIED
] = { .type
= NLA_U32
},
222 [CTA_TIMEOUT_UDP_REPLIED
] = { .type
= NLA_U32
},
224 #endif /* CONFIG_NF_CONNTRACK_TIMEOUT */
227 static struct ctl_table udp_sysctl_table
[] = {
229 .procname
= "nf_conntrack_udp_timeout",
230 .maxlen
= sizeof(unsigned int),
232 .proc_handler
= proc_dointvec_jiffies
,
235 .procname
= "nf_conntrack_udp_timeout_stream",
236 .maxlen
= sizeof(unsigned int),
238 .proc_handler
= proc_dointvec_jiffies
,
242 #endif /* CONFIG_SYSCTL */
244 static int udp_kmemdup_sysctl_table(struct nf_proto_net
*pn
,
245 struct nf_udp_net
*un
)
250 pn
->ctl_table
= kmemdup(udp_sysctl_table
,
251 sizeof(udp_sysctl_table
),
255 pn
->ctl_table
[0].data
= &un
->timeouts
[UDP_CT_UNREPLIED
];
256 pn
->ctl_table
[1].data
= &un
->timeouts
[UDP_CT_REPLIED
];
261 static int udp_init_net(struct net
*net
, u_int16_t proto
)
263 struct nf_udp_net
*un
= udp_pernet(net
);
264 struct nf_proto_net
*pn
= &un
->pn
;
269 for (i
= 0; i
< UDP_CT_MAX
; i
++)
270 un
->timeouts
[i
] = udp_timeouts
[i
];
273 return udp_kmemdup_sysctl_table(pn
, un
);
276 static struct nf_proto_net
*udp_get_net_proto(struct net
*net
)
278 return &net
->ct
.nf_ct_proto
.udp
.pn
;
281 const struct nf_conntrack_l4proto nf_conntrack_l4proto_udp4
=
284 .l4proto
= IPPROTO_UDP
,
286 .packet
= udp_packet
,
289 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
290 .tuple_to_nlattr
= nf_ct_port_tuple_to_nlattr
,
291 .nlattr_to_tuple
= nf_ct_port_nlattr_to_tuple
,
292 .nlattr_tuple_size
= nf_ct_port_nlattr_tuple_size
,
293 .nla_policy
= nf_ct_port_nla_policy
,
295 #ifdef CONFIG_NF_CONNTRACK_TIMEOUT
297 .nlattr_to_obj
= udp_timeout_nlattr_to_obj
,
298 .obj_to_nlattr
= udp_timeout_obj_to_nlattr
,
299 .nlattr_max
= CTA_TIMEOUT_UDP_MAX
,
300 .obj_size
= sizeof(unsigned int) * CTA_TIMEOUT_UDP_MAX
,
301 .nla_policy
= udp_timeout_nla_policy
,
303 #endif /* CONFIG_NF_CONNTRACK_TIMEOUT */
304 .init_net
= udp_init_net
,
305 .get_net_proto
= udp_get_net_proto
,
307 EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_udp4
);
309 #ifdef CONFIG_NF_CT_PROTO_UDPLITE
310 const struct nf_conntrack_l4proto nf_conntrack_l4proto_udplite4
=
313 .l4proto
= IPPROTO_UDPLITE
,
315 .packet
= udp_packet
,
317 .error
= udplite_error
,
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 #ifdef CONFIG_NF_CONNTRACK_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_CONNTRACK_TIMEOUT */
333 .init_net
= udp_init_net
,
334 .get_net_proto
= udp_get_net_proto
,
336 EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_udplite4
);
339 const struct nf_conntrack_l4proto nf_conntrack_l4proto_udp6
=
342 .l4proto
= IPPROTO_UDP
,
344 .packet
= udp_packet
,
347 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
348 .tuple_to_nlattr
= nf_ct_port_tuple_to_nlattr
,
349 .nlattr_to_tuple
= nf_ct_port_nlattr_to_tuple
,
350 .nlattr_tuple_size
= nf_ct_port_nlattr_tuple_size
,
351 .nla_policy
= nf_ct_port_nla_policy
,
353 #ifdef CONFIG_NF_CONNTRACK_TIMEOUT
355 .nlattr_to_obj
= udp_timeout_nlattr_to_obj
,
356 .obj_to_nlattr
= udp_timeout_obj_to_nlattr
,
357 .nlattr_max
= CTA_TIMEOUT_UDP_MAX
,
358 .obj_size
= sizeof(unsigned int) * CTA_TIMEOUT_UDP_MAX
,
359 .nla_policy
= udp_timeout_nla_policy
,
361 #endif /* CONFIG_NF_CONNTRACK_TIMEOUT */
362 .init_net
= udp_init_net
,
363 .get_net_proto
= udp_get_net_proto
,
365 EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_udp6
);
367 #ifdef CONFIG_NF_CT_PROTO_UDPLITE
368 const struct nf_conntrack_l4proto nf_conntrack_l4proto_udplite6
=
371 .l4proto
= IPPROTO_UDPLITE
,
373 .packet
= udp_packet
,
375 .error
= udplite_error
,
376 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
377 .tuple_to_nlattr
= nf_ct_port_tuple_to_nlattr
,
378 .nlattr_to_tuple
= nf_ct_port_nlattr_to_tuple
,
379 .nlattr_tuple_size
= nf_ct_port_nlattr_tuple_size
,
380 .nla_policy
= nf_ct_port_nla_policy
,
382 #ifdef CONFIG_NF_CONNTRACK_TIMEOUT
384 .nlattr_to_obj
= udp_timeout_nlattr_to_obj
,
385 .obj_to_nlattr
= udp_timeout_obj_to_nlattr
,
386 .nlattr_max
= CTA_TIMEOUT_UDP_MAX
,
387 .obj_size
= sizeof(unsigned int) * CTA_TIMEOUT_UDP_MAX
,
388 .nla_policy
= udp_timeout_nla_policy
,
390 #endif /* CONFIG_NF_CONNTRACK_TIMEOUT */
391 .init_net
= udp_init_net
,
392 .get_net_proto
= udp_get_net_proto
,
394 EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_udplite6
);