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,
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,
77 unsigned int *timeouts)
79 /* If we've seen traffic both ways, this is some kind of UDP
80 stream. Extend timeout. */
81 if (test_bit(IPS_SEEN_REPLY_BIT, &ct->status)) {
82 nf_ct_refresh_acct(ct, ctinfo, skb,
83 timeouts[UDP_CT_REPLIED]);
84 /* Also, more likely to be important, and not a probe */
85 if (!test_and_set_bit(IPS_ASSURED_BIT, &ct->status))
86 nf_conntrack_event_cache(IPCT_ASSURED, ct);
88 nf_ct_refresh_acct(ct, ctinfo, skb,
89 timeouts[UDP_CT_UNREPLIED]);
94 /* Called when a new connection for this protocol found. */
95 static bool udp_new(struct nf_conn *ct, const struct sk_buff *skb,
96 unsigned int dataoff, unsigned int *timeouts)
101 #ifdef CONFIG_NF_CT_PROTO_UDPLITE
102 static int udplite_error(struct net *net, struct nf_conn *tmpl,
104 unsigned int dataoff,
105 u8 pf, unsigned int hooknum)
107 unsigned int udplen = skb->len - dataoff;
108 const struct udphdr *hdr;
112 /* Header is too small? */
113 hdr = skb_header_pointer(skb, dataoff, sizeof(_hdr), &_hdr);
115 if (LOG_INVALID(net, IPPROTO_UDPLITE))
116 nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
117 "nf_ct_udplite: short packet ");
121 cscov = ntohs(hdr->len);
124 } else if (cscov < sizeof(*hdr) || cscov > udplen) {
125 if (LOG_INVALID(net, IPPROTO_UDPLITE))
126 nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
127 "nf_ct_udplite: invalid checksum coverage ");
131 /* UDPLITE mandates checksums */
133 if (LOG_INVALID(net, IPPROTO_UDPLITE))
134 nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
135 "nf_ct_udplite: checksum missing ");
139 /* Checksum invalid? Ignore. */
140 if (net->ct.sysctl_checksum && hooknum == NF_INET_PRE_ROUTING &&
141 nf_checksum_partial(skb, hooknum, dataoff, cscov, IPPROTO_UDP,
143 if (LOG_INVALID(net, IPPROTO_UDPLITE))
144 nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
145 "nf_ct_udplite: bad UDPLite checksum ");
153 static int udp_error(struct net *net, struct nf_conn *tmpl, struct sk_buff *skb,
154 unsigned int dataoff,
156 unsigned int hooknum)
158 unsigned int udplen = skb->len - dataoff;
159 const struct udphdr *hdr;
162 /* Header is too small? */
163 hdr = skb_header_pointer(skb, dataoff, sizeof(_hdr), &_hdr);
165 if (LOG_INVALID(net, IPPROTO_UDP))
166 nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
167 "nf_ct_udp: short packet ");
171 /* Truncated/malformed packets */
172 if (ntohs(hdr->len) > udplen || ntohs(hdr->len) < sizeof(*hdr)) {
173 if (LOG_INVALID(net, IPPROTO_UDP))
174 nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
175 "nf_ct_udp: truncated/malformed packet ");
179 /* Packet with no checksum */
183 /* Checksum invalid? Ignore.
184 * We skip checking packets on the outgoing path
185 * because the checksum is assumed to be correct.
186 * FIXME: Source route IP option packets --RR */
187 if (net->ct.sysctl_checksum && hooknum == NF_INET_PRE_ROUTING &&
188 nf_checksum(skb, hooknum, dataoff, IPPROTO_UDP, pf)) {
189 if (LOG_INVALID(net, IPPROTO_UDP))
190 nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
191 "nf_ct_udp: bad UDP checksum ");
198 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
200 #include <linux/netfilter/nfnetlink.h>
201 #include <linux/netfilter/nfnetlink_cttimeout.h>
203 static int udp_timeout_nlattr_to_obj(struct nlattr *tb[],
204 struct net *net, void *data)
206 unsigned int *timeouts = data;
207 struct nf_udp_net *un = udp_pernet(net);
209 /* set default timeouts for UDP. */
210 timeouts[UDP_CT_UNREPLIED] = un->timeouts[UDP_CT_UNREPLIED];
211 timeouts[UDP_CT_REPLIED] = un->timeouts[UDP_CT_REPLIED];
213 if (tb[CTA_TIMEOUT_UDP_UNREPLIED]) {
214 timeouts[UDP_CT_UNREPLIED] =
215 ntohl(nla_get_be32(tb[CTA_TIMEOUT_UDP_UNREPLIED])) * HZ;
217 if (tb[CTA_TIMEOUT_UDP_REPLIED]) {
218 timeouts[UDP_CT_REPLIED] =
219 ntohl(nla_get_be32(tb[CTA_TIMEOUT_UDP_REPLIED])) * HZ;
225 udp_timeout_obj_to_nlattr(struct sk_buff *skb, const void *data)
227 const unsigned int *timeouts = data;
229 if (nla_put_be32(skb, CTA_TIMEOUT_UDP_UNREPLIED,
230 htonl(timeouts[UDP_CT_UNREPLIED] / HZ)) ||
231 nla_put_be32(skb, CTA_TIMEOUT_UDP_REPLIED,
232 htonl(timeouts[UDP_CT_REPLIED] / HZ)))
233 goto nla_put_failure;
240 static const struct nla_policy
241 udp_timeout_nla_policy[CTA_TIMEOUT_UDP_MAX+1] = {
242 [CTA_TIMEOUT_UDP_UNREPLIED] = { .type = NLA_U32 },
243 [CTA_TIMEOUT_UDP_REPLIED] = { .type = NLA_U32 },
245 #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
248 static struct ctl_table udp_sysctl_table[] = {
250 .procname = "nf_conntrack_udp_timeout",
251 .maxlen = sizeof(unsigned int),
253 .proc_handler = proc_dointvec_jiffies,
256 .procname = "nf_conntrack_udp_timeout_stream",
257 .maxlen = sizeof(unsigned int),
259 .proc_handler = proc_dointvec_jiffies,
263 #endif /* CONFIG_SYSCTL */
265 static int udp_kmemdup_sysctl_table(struct nf_proto_net *pn,
266 struct nf_udp_net *un)
271 pn->ctl_table = kmemdup(udp_sysctl_table,
272 sizeof(udp_sysctl_table),
276 pn->ctl_table[0].data = &un->timeouts[UDP_CT_UNREPLIED];
277 pn->ctl_table[1].data = &un->timeouts[UDP_CT_REPLIED];
282 static int udp_init_net(struct net *net, u_int16_t proto)
284 struct nf_udp_net *un = udp_pernet(net);
285 struct nf_proto_net *pn = &un->pn;
290 for (i = 0; i < UDP_CT_MAX; i++)
291 un->timeouts[i] = udp_timeouts[i];
294 return udp_kmemdup_sysctl_table(pn, un);
297 static struct nf_proto_net *udp_get_net_proto(struct net *net)
299 return &net->ct.nf_ct_proto.udp.pn;
302 struct nf_conntrack_l4proto nf_conntrack_l4proto_udp4 __read_mostly =
305 .l4proto = IPPROTO_UDP,
307 .pkt_to_tuple = udp_pkt_to_tuple,
308 .invert_tuple = udp_invert_tuple,
309 .packet = udp_packet,
310 .get_timeouts = udp_get_timeouts,
313 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
314 .tuple_to_nlattr = nf_ct_port_tuple_to_nlattr,
315 .nlattr_to_tuple = nf_ct_port_nlattr_to_tuple,
316 .nlattr_tuple_size = nf_ct_port_nlattr_tuple_size,
317 .nla_policy = nf_ct_port_nla_policy,
319 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
321 .nlattr_to_obj = udp_timeout_nlattr_to_obj,
322 .obj_to_nlattr = udp_timeout_obj_to_nlattr,
323 .nlattr_max = CTA_TIMEOUT_UDP_MAX,
324 .obj_size = sizeof(unsigned int) * CTA_TIMEOUT_UDP_MAX,
325 .nla_policy = udp_timeout_nla_policy,
327 #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
328 .init_net = udp_init_net,
329 .get_net_proto = udp_get_net_proto,
331 EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_udp4);
333 #ifdef CONFIG_NF_CT_PROTO_UDPLITE
334 struct nf_conntrack_l4proto nf_conntrack_l4proto_udplite4 __read_mostly =
337 .l4proto = IPPROTO_UDPLITE,
339 .pkt_to_tuple = udp_pkt_to_tuple,
340 .invert_tuple = udp_invert_tuple,
341 .packet = udp_packet,
342 .get_timeouts = udp_get_timeouts,
344 .error = udplite_error,
345 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
346 .tuple_to_nlattr = nf_ct_port_tuple_to_nlattr,
347 .nlattr_to_tuple = nf_ct_port_nlattr_to_tuple,
348 .nlattr_tuple_size = nf_ct_port_nlattr_tuple_size,
349 .nla_policy = nf_ct_port_nla_policy,
351 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
353 .nlattr_to_obj = udp_timeout_nlattr_to_obj,
354 .obj_to_nlattr = udp_timeout_obj_to_nlattr,
355 .nlattr_max = CTA_TIMEOUT_UDP_MAX,
356 .obj_size = sizeof(unsigned int) * CTA_TIMEOUT_UDP_MAX,
357 .nla_policy = udp_timeout_nla_policy,
359 #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
360 .init_net = udp_init_net,
361 .get_net_proto = udp_get_net_proto,
363 EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_udplite4);
366 struct nf_conntrack_l4proto nf_conntrack_l4proto_udp6 __read_mostly =
369 .l4proto = IPPROTO_UDP,
371 .pkt_to_tuple = udp_pkt_to_tuple,
372 .invert_tuple = udp_invert_tuple,
373 .packet = udp_packet,
374 .get_timeouts = udp_get_timeouts,
377 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
378 .tuple_to_nlattr = nf_ct_port_tuple_to_nlattr,
379 .nlattr_to_tuple = nf_ct_port_nlattr_to_tuple,
380 .nlattr_tuple_size = nf_ct_port_nlattr_tuple_size,
381 .nla_policy = nf_ct_port_nla_policy,
383 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
385 .nlattr_to_obj = udp_timeout_nlattr_to_obj,
386 .obj_to_nlattr = udp_timeout_obj_to_nlattr,
387 .nlattr_max = CTA_TIMEOUT_UDP_MAX,
388 .obj_size = sizeof(unsigned int) * CTA_TIMEOUT_UDP_MAX,
389 .nla_policy = udp_timeout_nla_policy,
391 #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
392 .init_net = udp_init_net,
393 .get_net_proto = udp_get_net_proto,
395 EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_udp6);
397 #ifdef CONFIG_NF_CT_PROTO_UDPLITE
398 struct nf_conntrack_l4proto nf_conntrack_l4proto_udplite6 __read_mostly =
401 .l4proto = IPPROTO_UDPLITE,
403 .pkt_to_tuple = udp_pkt_to_tuple,
404 .invert_tuple = udp_invert_tuple,
405 .packet = udp_packet,
406 .get_timeouts = udp_get_timeouts,
408 .error = udplite_error,
409 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
410 .tuple_to_nlattr = nf_ct_port_tuple_to_nlattr,
411 .nlattr_to_tuple = nf_ct_port_nlattr_to_tuple,
412 .nlattr_tuple_size = nf_ct_port_nlattr_tuple_size,
413 .nla_policy = nf_ct_port_nla_policy,
415 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
417 .nlattr_to_obj = udp_timeout_nlattr_to_obj,
418 .obj_to_nlattr = udp_timeout_obj_to_nlattr,
419 .nlattr_max = CTA_TIMEOUT_UDP_MAX,
420 .obj_size = sizeof(unsigned int) * CTA_TIMEOUT_UDP_MAX,
421 .nla_policy = udp_timeout_nla_policy,
423 #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
424 .init_net = udp_init_net,
425 .get_net_proto = udp_get_net_proto,
427 EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_udplite6);