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 const 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
,
42 struct nf_conntrack_tuple
*tuple
)
44 const struct udphdr
*hp
;
47 /* Actually only need first 4 bytes to get ports. */
48 hp
= skb_header_pointer(skb
, dataoff
, 4, &_hdr
);
52 tuple
->src
.u
.udp
.port
= hp
->source
;
53 tuple
->dst
.u
.udp
.port
= hp
->dest
;
58 static bool udp_invert_tuple(struct nf_conntrack_tuple
*tuple
,
59 const struct nf_conntrack_tuple
*orig
)
61 tuple
->src
.u
.udp
.port
= orig
->dst
.u
.udp
.port
;
62 tuple
->dst
.u
.udp
.port
= orig
->src
.u
.udp
.port
;
66 static unsigned int *udp_get_timeouts(struct net
*net
)
68 return udp_pernet(net
)->timeouts
;
71 /* Returns verdict for packet, and may modify conntracktype */
72 static int udp_packet(struct nf_conn
*ct
,
73 const struct sk_buff
*skb
,
75 enum ip_conntrack_info ctinfo
,
76 unsigned int *timeouts
)
78 /* If we've seen traffic both ways, this is some kind of UDP
79 stream. Extend timeout. */
80 if (test_bit(IPS_SEEN_REPLY_BIT
, &ct
->status
)) {
81 nf_ct_refresh_acct(ct
, ctinfo
, skb
,
82 timeouts
[UDP_CT_REPLIED
]);
83 /* Also, more likely to be important, and not a probe */
84 if (!test_and_set_bit(IPS_ASSURED_BIT
, &ct
->status
))
85 nf_conntrack_event_cache(IPCT_ASSURED
, ct
);
87 nf_ct_refresh_acct(ct
, ctinfo
, skb
,
88 timeouts
[UDP_CT_UNREPLIED
]);
93 /* Called when a new connection for this protocol found. */
94 static bool udp_new(struct nf_conn
*ct
, const struct sk_buff
*skb
,
95 unsigned int dataoff
, unsigned int *timeouts
)
100 #ifdef CONFIG_NF_CT_PROTO_UDPLITE
101 static void udplite_error_log(const struct sk_buff
*skb
, struct net
*net
,
102 u8 pf
, const char *msg
)
104 nf_l4proto_log_invalid(skb
, net
, pf
, IPPROTO_UDPLITE
, "%s", msg
);
107 static int udplite_error(struct net
*net
, struct nf_conn
*tmpl
,
109 unsigned int dataoff
,
110 u8 pf
, unsigned int hooknum
)
112 unsigned int udplen
= skb
->len
- dataoff
;
113 const struct udphdr
*hdr
;
117 /* Header is too small? */
118 hdr
= skb_header_pointer(skb
, dataoff
, sizeof(_hdr
), &_hdr
);
120 udplite_error_log(skb
, net
, pf
, "short packet");
124 cscov
= ntohs(hdr
->len
);
127 } else if (cscov
< sizeof(*hdr
) || cscov
> udplen
) {
128 udplite_error_log(skb
, net
, pf
, "invalid checksum coverage");
132 /* UDPLITE mandates checksums */
134 udplite_error_log(skb
, net
, pf
, "checksum missing");
138 /* Checksum invalid? Ignore. */
139 if (net
->ct
.sysctl_checksum
&& hooknum
== NF_INET_PRE_ROUTING
&&
140 nf_checksum_partial(skb
, hooknum
, dataoff
, cscov
, IPPROTO_UDP
,
142 udplite_error_log(skb
, net
, pf
, "bad checksum");
150 static void udp_error_log(const struct sk_buff
*skb
, struct net
*net
,
151 u8 pf
, const char *msg
)
153 nf_l4proto_log_invalid(skb
, net
, pf
, IPPROTO_UDP
, "%s", msg
);
156 static int udp_error(struct net
*net
, struct nf_conn
*tmpl
, struct sk_buff
*skb
,
157 unsigned int dataoff
,
159 unsigned int hooknum
)
161 unsigned int udplen
= skb
->len
- dataoff
;
162 const struct udphdr
*hdr
;
165 /* Header is too small? */
166 hdr
= skb_header_pointer(skb
, dataoff
, sizeof(_hdr
), &_hdr
);
168 udp_error_log(skb
, net
, pf
, "short packet");
172 /* Truncated/malformed packets */
173 if (ntohs(hdr
->len
) > udplen
|| ntohs(hdr
->len
) < sizeof(*hdr
)) {
174 udp_error_log(skb
, net
, pf
, "truncated/malformed packet");
178 /* Packet with no checksum */
182 /* Checksum invalid? Ignore.
183 * We skip checking packets on the outgoing path
184 * because the checksum is assumed to be correct.
185 * FIXME: Source route IP option packets --RR */
186 if (net
->ct
.sysctl_checksum
&& hooknum
== NF_INET_PRE_ROUTING
&&
187 nf_checksum(skb
, hooknum
, dataoff
, IPPROTO_UDP
, pf
)) {
188 udp_error_log(skb
, net
, pf
, "bad checksum");
195 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
197 #include <linux/netfilter/nfnetlink.h>
198 #include <linux/netfilter/nfnetlink_cttimeout.h>
200 static int udp_timeout_nlattr_to_obj(struct nlattr
*tb
[],
201 struct net
*net
, void *data
)
203 unsigned int *timeouts
= data
;
204 struct nf_udp_net
*un
= udp_pernet(net
);
206 /* set default timeouts for UDP. */
207 timeouts
[UDP_CT_UNREPLIED
] = un
->timeouts
[UDP_CT_UNREPLIED
];
208 timeouts
[UDP_CT_REPLIED
] = un
->timeouts
[UDP_CT_REPLIED
];
210 if (tb
[CTA_TIMEOUT_UDP_UNREPLIED
]) {
211 timeouts
[UDP_CT_UNREPLIED
] =
212 ntohl(nla_get_be32(tb
[CTA_TIMEOUT_UDP_UNREPLIED
])) * HZ
;
214 if (tb
[CTA_TIMEOUT_UDP_REPLIED
]) {
215 timeouts
[UDP_CT_REPLIED
] =
216 ntohl(nla_get_be32(tb
[CTA_TIMEOUT_UDP_REPLIED
])) * HZ
;
222 udp_timeout_obj_to_nlattr(struct sk_buff
*skb
, const void *data
)
224 const unsigned int *timeouts
= data
;
226 if (nla_put_be32(skb
, CTA_TIMEOUT_UDP_UNREPLIED
,
227 htonl(timeouts
[UDP_CT_UNREPLIED
] / HZ
)) ||
228 nla_put_be32(skb
, CTA_TIMEOUT_UDP_REPLIED
,
229 htonl(timeouts
[UDP_CT_REPLIED
] / HZ
)))
230 goto nla_put_failure
;
237 static const struct nla_policy
238 udp_timeout_nla_policy
[CTA_TIMEOUT_UDP_MAX
+1] = {
239 [CTA_TIMEOUT_UDP_UNREPLIED
] = { .type
= NLA_U32
},
240 [CTA_TIMEOUT_UDP_REPLIED
] = { .type
= NLA_U32
},
242 #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
245 static struct ctl_table udp_sysctl_table
[] = {
247 .procname
= "nf_conntrack_udp_timeout",
248 .maxlen
= sizeof(unsigned int),
250 .proc_handler
= proc_dointvec_jiffies
,
253 .procname
= "nf_conntrack_udp_timeout_stream",
254 .maxlen
= sizeof(unsigned int),
256 .proc_handler
= proc_dointvec_jiffies
,
260 #endif /* CONFIG_SYSCTL */
262 static int udp_kmemdup_sysctl_table(struct nf_proto_net
*pn
,
263 struct nf_udp_net
*un
)
268 pn
->ctl_table
= kmemdup(udp_sysctl_table
,
269 sizeof(udp_sysctl_table
),
273 pn
->ctl_table
[0].data
= &un
->timeouts
[UDP_CT_UNREPLIED
];
274 pn
->ctl_table
[1].data
= &un
->timeouts
[UDP_CT_REPLIED
];
279 static int udp_init_net(struct net
*net
, u_int16_t proto
)
281 struct nf_udp_net
*un
= udp_pernet(net
);
282 struct nf_proto_net
*pn
= &un
->pn
;
287 for (i
= 0; i
< UDP_CT_MAX
; i
++)
288 un
->timeouts
[i
] = udp_timeouts
[i
];
291 return udp_kmemdup_sysctl_table(pn
, un
);
294 static struct nf_proto_net
*udp_get_net_proto(struct net
*net
)
296 return &net
->ct
.nf_ct_proto
.udp
.pn
;
299 const struct nf_conntrack_l4proto nf_conntrack_l4proto_udp4
=
302 .l4proto
= IPPROTO_UDP
,
304 .pkt_to_tuple
= udp_pkt_to_tuple
,
305 .invert_tuple
= udp_invert_tuple
,
306 .packet
= udp_packet
,
307 .get_timeouts
= udp_get_timeouts
,
310 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
311 .tuple_to_nlattr
= nf_ct_port_tuple_to_nlattr
,
312 .nlattr_to_tuple
= nf_ct_port_nlattr_to_tuple
,
313 .nlattr_tuple_size
= nf_ct_port_nlattr_tuple_size
,
314 .nla_policy
= nf_ct_port_nla_policy
,
316 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
318 .nlattr_to_obj
= udp_timeout_nlattr_to_obj
,
319 .obj_to_nlattr
= udp_timeout_obj_to_nlattr
,
320 .nlattr_max
= CTA_TIMEOUT_UDP_MAX
,
321 .obj_size
= sizeof(unsigned int) * CTA_TIMEOUT_UDP_MAX
,
322 .nla_policy
= udp_timeout_nla_policy
,
324 #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
325 .init_net
= udp_init_net
,
326 .get_net_proto
= udp_get_net_proto
,
328 EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_udp4
);
330 #ifdef CONFIG_NF_CT_PROTO_UDPLITE
331 const struct nf_conntrack_l4proto nf_conntrack_l4proto_udplite4
=
334 .l4proto
= IPPROTO_UDPLITE
,
336 .pkt_to_tuple
= udp_pkt_to_tuple
,
337 .invert_tuple
= udp_invert_tuple
,
338 .packet
= udp_packet
,
339 .get_timeouts
= udp_get_timeouts
,
341 .error
= udplite_error
,
342 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
343 .tuple_to_nlattr
= nf_ct_port_tuple_to_nlattr
,
344 .nlattr_to_tuple
= nf_ct_port_nlattr_to_tuple
,
345 .nlattr_tuple_size
= nf_ct_port_nlattr_tuple_size
,
346 .nla_policy
= nf_ct_port_nla_policy
,
348 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
350 .nlattr_to_obj
= udp_timeout_nlattr_to_obj
,
351 .obj_to_nlattr
= udp_timeout_obj_to_nlattr
,
352 .nlattr_max
= CTA_TIMEOUT_UDP_MAX
,
353 .obj_size
= sizeof(unsigned int) * CTA_TIMEOUT_UDP_MAX
,
354 .nla_policy
= udp_timeout_nla_policy
,
356 #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
357 .init_net
= udp_init_net
,
358 .get_net_proto
= udp_get_net_proto
,
360 EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_udplite4
);
363 const struct nf_conntrack_l4proto nf_conntrack_l4proto_udp6
=
366 .l4proto
= IPPROTO_UDP
,
368 .pkt_to_tuple
= udp_pkt_to_tuple
,
369 .invert_tuple
= udp_invert_tuple
,
370 .packet
= udp_packet
,
371 .get_timeouts
= udp_get_timeouts
,
374 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
375 .tuple_to_nlattr
= nf_ct_port_tuple_to_nlattr
,
376 .nlattr_to_tuple
= nf_ct_port_nlattr_to_tuple
,
377 .nlattr_tuple_size
= nf_ct_port_nlattr_tuple_size
,
378 .nla_policy
= nf_ct_port_nla_policy
,
380 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
382 .nlattr_to_obj
= udp_timeout_nlattr_to_obj
,
383 .obj_to_nlattr
= udp_timeout_obj_to_nlattr
,
384 .nlattr_max
= CTA_TIMEOUT_UDP_MAX
,
385 .obj_size
= sizeof(unsigned int) * CTA_TIMEOUT_UDP_MAX
,
386 .nla_policy
= udp_timeout_nla_policy
,
388 #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
389 .init_net
= udp_init_net
,
390 .get_net_proto
= udp_get_net_proto
,
392 EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_udp6
);
394 #ifdef CONFIG_NF_CT_PROTO_UDPLITE
395 const struct nf_conntrack_l4proto nf_conntrack_l4proto_udplite6
=
398 .l4proto
= IPPROTO_UDPLITE
,
400 .pkt_to_tuple
= udp_pkt_to_tuple
,
401 .invert_tuple
= udp_invert_tuple
,
402 .packet
= udp_packet
,
403 .get_timeouts
= udp_get_timeouts
,
405 .error
= udplite_error
,
406 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
407 .tuple_to_nlattr
= nf_ct_port_tuple_to_nlattr
,
408 .nlattr_to_tuple
= nf_ct_port_nlattr_to_tuple
,
409 .nlattr_tuple_size
= nf_ct_port_nlattr_tuple_size
,
410 .nla_policy
= nf_ct_port_nla_policy
,
412 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
414 .nlattr_to_obj
= udp_timeout_nlattr_to_obj
,
415 .obj_to_nlattr
= udp_timeout_obj_to_nlattr
,
416 .nlattr_max
= CTA_TIMEOUT_UDP_MAX
,
417 .obj_size
= sizeof(unsigned int) * CTA_TIMEOUT_UDP_MAX
,
418 .nla_policy
= udp_timeout_nla_policy
,
420 #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
421 .init_net
= udp_init_net
,
422 .get_net_proto
= udp_get_net_proto
,
424 EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_udplite6
);