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 /* Print out the per-protocol part of the tuple. */
67 static void udp_print_tuple(struct seq_file *s,
68 const struct nf_conntrack_tuple *tuple)
70 seq_printf(s, "sport=%hu dport=%hu ",
71 ntohs(tuple->src.u.udp.port),
72 ntohs(tuple->dst.u.udp.port));
75 static unsigned int *udp_get_timeouts(struct net *net)
77 return udp_pernet(net)->timeouts;
80 /* Returns verdict for packet, and may modify conntracktype */
81 static int udp_packet(struct nf_conn *ct,
82 const struct sk_buff *skb,
84 enum ip_conntrack_info ctinfo,
87 unsigned int *timeouts)
89 /* If we've seen traffic both ways, this is some kind of UDP
90 stream. Extend timeout. */
91 if (test_bit(IPS_SEEN_REPLY_BIT, &ct->status)) {
92 nf_ct_refresh_acct(ct, ctinfo, skb,
93 timeouts[UDP_CT_REPLIED]);
94 /* Also, more likely to be important, and not a probe */
95 if (!test_and_set_bit(IPS_ASSURED_BIT, &ct->status))
96 nf_conntrack_event_cache(IPCT_ASSURED, ct);
98 nf_ct_refresh_acct(ct, ctinfo, skb,
99 timeouts[UDP_CT_UNREPLIED]);
104 /* Called when a new connection for this protocol found. */
105 static bool udp_new(struct nf_conn *ct, const struct sk_buff *skb,
106 unsigned int dataoff, unsigned int *timeouts)
111 #ifdef CONFIG_NF_CT_PROTO_UDPLITE
112 static int udplite_error(struct net *net, struct nf_conn *tmpl,
114 unsigned int dataoff,
115 u8 pf, unsigned int hooknum)
117 unsigned int udplen = skb->len - dataoff;
118 const struct udphdr *hdr;
122 /* Header is too small? */
123 hdr = skb_header_pointer(skb, dataoff, sizeof(_hdr), &_hdr);
125 if (LOG_INVALID(net, IPPROTO_UDPLITE))
126 nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
127 "nf_ct_udplite: short packet ");
131 cscov = ntohs(hdr->len);
134 } else if (cscov < sizeof(*hdr) || cscov > udplen) {
135 if (LOG_INVALID(net, IPPROTO_UDPLITE))
136 nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
137 "nf_ct_udplite: invalid checksum coverage ");
141 /* UDPLITE mandates checksums */
143 if (LOG_INVALID(net, IPPROTO_UDPLITE))
144 nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
145 "nf_ct_udplite: checksum missing ");
149 /* Checksum invalid? Ignore. */
150 if (net->ct.sysctl_checksum && hooknum == NF_INET_PRE_ROUTING &&
151 nf_checksum_partial(skb, hooknum, dataoff, cscov, IPPROTO_UDP,
153 if (LOG_INVALID(net, IPPROTO_UDPLITE))
154 nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
155 "nf_ct_udplite: bad UDPLite checksum ");
163 static int udp_error(struct net *net, struct nf_conn *tmpl, struct sk_buff *skb,
164 unsigned int dataoff,
166 unsigned int hooknum)
168 unsigned int udplen = skb->len - dataoff;
169 const struct udphdr *hdr;
172 /* Header is too small? */
173 hdr = skb_header_pointer(skb, dataoff, sizeof(_hdr), &_hdr);
175 if (LOG_INVALID(net, IPPROTO_UDP))
176 nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
177 "nf_ct_udp: short packet ");
181 /* Truncated/malformed packets */
182 if (ntohs(hdr->len) > udplen || ntohs(hdr->len) < sizeof(*hdr)) {
183 if (LOG_INVALID(net, IPPROTO_UDP))
184 nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
185 "nf_ct_udp: truncated/malformed packet ");
189 /* Packet with no checksum */
193 /* Checksum invalid? Ignore.
194 * We skip checking packets on the outgoing path
195 * because the checksum is assumed to be correct.
196 * FIXME: Source route IP option packets --RR */
197 if (net->ct.sysctl_checksum && hooknum == NF_INET_PRE_ROUTING &&
198 nf_checksum(skb, hooknum, dataoff, IPPROTO_UDP, pf)) {
199 if (LOG_INVALID(net, IPPROTO_UDP))
200 nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
201 "nf_ct_udp: bad UDP checksum ");
208 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
210 #include <linux/netfilter/nfnetlink.h>
211 #include <linux/netfilter/nfnetlink_cttimeout.h>
213 static int udp_timeout_nlattr_to_obj(struct nlattr *tb[],
214 struct net *net, void *data)
216 unsigned int *timeouts = data;
217 struct nf_udp_net *un = udp_pernet(net);
219 /* set default timeouts for UDP. */
220 timeouts[UDP_CT_UNREPLIED] = un->timeouts[UDP_CT_UNREPLIED];
221 timeouts[UDP_CT_REPLIED] = un->timeouts[UDP_CT_REPLIED];
223 if (tb[CTA_TIMEOUT_UDP_UNREPLIED]) {
224 timeouts[UDP_CT_UNREPLIED] =
225 ntohl(nla_get_be32(tb[CTA_TIMEOUT_UDP_UNREPLIED])) * HZ;
227 if (tb[CTA_TIMEOUT_UDP_REPLIED]) {
228 timeouts[UDP_CT_REPLIED] =
229 ntohl(nla_get_be32(tb[CTA_TIMEOUT_UDP_REPLIED])) * HZ;
235 udp_timeout_obj_to_nlattr(struct sk_buff *skb, const void *data)
237 const unsigned int *timeouts = data;
239 if (nla_put_be32(skb, CTA_TIMEOUT_UDP_UNREPLIED,
240 htonl(timeouts[UDP_CT_UNREPLIED] / HZ)) ||
241 nla_put_be32(skb, CTA_TIMEOUT_UDP_REPLIED,
242 htonl(timeouts[UDP_CT_REPLIED] / HZ)))
243 goto nla_put_failure;
250 static const struct nla_policy
251 udp_timeout_nla_policy[CTA_TIMEOUT_UDP_MAX+1] = {
252 [CTA_TIMEOUT_UDP_UNREPLIED] = { .type = NLA_U32 },
253 [CTA_TIMEOUT_UDP_REPLIED] = { .type = NLA_U32 },
255 #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
258 static struct ctl_table udp_sysctl_table[] = {
260 .procname = "nf_conntrack_udp_timeout",
261 .maxlen = sizeof(unsigned int),
263 .proc_handler = proc_dointvec_jiffies,
266 .procname = "nf_conntrack_udp_timeout_stream",
267 .maxlen = sizeof(unsigned int),
269 .proc_handler = proc_dointvec_jiffies,
273 #endif /* CONFIG_SYSCTL */
275 static int udp_kmemdup_sysctl_table(struct nf_proto_net *pn,
276 struct nf_udp_net *un)
281 pn->ctl_table = kmemdup(udp_sysctl_table,
282 sizeof(udp_sysctl_table),
286 pn->ctl_table[0].data = &un->timeouts[UDP_CT_UNREPLIED];
287 pn->ctl_table[1].data = &un->timeouts[UDP_CT_REPLIED];
292 static int udp_init_net(struct net *net, u_int16_t proto)
294 struct nf_udp_net *un = udp_pernet(net);
295 struct nf_proto_net *pn = &un->pn;
300 for (i = 0; i < UDP_CT_MAX; i++)
301 un->timeouts[i] = udp_timeouts[i];
304 return udp_kmemdup_sysctl_table(pn, un);
307 static struct nf_proto_net *udp_get_net_proto(struct net *net)
309 return &net->ct.nf_ct_proto.udp.pn;
312 struct nf_conntrack_l4proto nf_conntrack_l4proto_udp4 __read_mostly =
315 .l4proto = IPPROTO_UDP,
318 .pkt_to_tuple = udp_pkt_to_tuple,
319 .invert_tuple = udp_invert_tuple,
320 .print_tuple = udp_print_tuple,
321 .packet = udp_packet,
322 .get_timeouts = udp_get_timeouts,
325 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
326 .tuple_to_nlattr = nf_ct_port_tuple_to_nlattr,
327 .nlattr_to_tuple = nf_ct_port_nlattr_to_tuple,
328 .nlattr_tuple_size = nf_ct_port_nlattr_tuple_size,
329 .nla_policy = nf_ct_port_nla_policy,
331 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
333 .nlattr_to_obj = udp_timeout_nlattr_to_obj,
334 .obj_to_nlattr = udp_timeout_obj_to_nlattr,
335 .nlattr_max = CTA_TIMEOUT_UDP_MAX,
336 .obj_size = sizeof(unsigned int) * CTA_TIMEOUT_UDP_MAX,
337 .nla_policy = udp_timeout_nla_policy,
339 #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
340 .init_net = udp_init_net,
341 .get_net_proto = udp_get_net_proto,
343 EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_udp4);
345 #ifdef CONFIG_NF_CT_PROTO_UDPLITE
346 struct nf_conntrack_l4proto nf_conntrack_l4proto_udplite4 __read_mostly =
349 .l4proto = IPPROTO_UDPLITE,
352 .pkt_to_tuple = udp_pkt_to_tuple,
353 .invert_tuple = udp_invert_tuple,
354 .print_tuple = udp_print_tuple,
355 .packet = udp_packet,
356 .get_timeouts = udp_get_timeouts,
358 .error = udplite_error,
359 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
360 .tuple_to_nlattr = nf_ct_port_tuple_to_nlattr,
361 .nlattr_to_tuple = nf_ct_port_nlattr_to_tuple,
362 .nlattr_tuple_size = nf_ct_port_nlattr_tuple_size,
363 .nla_policy = nf_ct_port_nla_policy,
365 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
367 .nlattr_to_obj = udp_timeout_nlattr_to_obj,
368 .obj_to_nlattr = udp_timeout_obj_to_nlattr,
369 .nlattr_max = CTA_TIMEOUT_UDP_MAX,
370 .obj_size = sizeof(unsigned int) * CTA_TIMEOUT_UDP_MAX,
371 .nla_policy = udp_timeout_nla_policy,
373 #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
374 .init_net = udp_init_net,
375 .get_net_proto = udp_get_net_proto,
377 EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_udplite4);
380 struct nf_conntrack_l4proto nf_conntrack_l4proto_udp6 __read_mostly =
383 .l4proto = IPPROTO_UDP,
386 .pkt_to_tuple = udp_pkt_to_tuple,
387 .invert_tuple = udp_invert_tuple,
388 .print_tuple = udp_print_tuple,
389 .packet = udp_packet,
390 .get_timeouts = udp_get_timeouts,
393 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
394 .tuple_to_nlattr = nf_ct_port_tuple_to_nlattr,
395 .nlattr_to_tuple = nf_ct_port_nlattr_to_tuple,
396 .nlattr_tuple_size = nf_ct_port_nlattr_tuple_size,
397 .nla_policy = nf_ct_port_nla_policy,
399 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
401 .nlattr_to_obj = udp_timeout_nlattr_to_obj,
402 .obj_to_nlattr = udp_timeout_obj_to_nlattr,
403 .nlattr_max = CTA_TIMEOUT_UDP_MAX,
404 .obj_size = sizeof(unsigned int) * CTA_TIMEOUT_UDP_MAX,
405 .nla_policy = udp_timeout_nla_policy,
407 #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
408 .init_net = udp_init_net,
409 .get_net_proto = udp_get_net_proto,
411 EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_udp6);
413 #ifdef CONFIG_NF_CT_PROTO_UDPLITE
414 struct nf_conntrack_l4proto nf_conntrack_l4proto_udplite6 __read_mostly =
417 .l4proto = IPPROTO_UDPLITE,
420 .pkt_to_tuple = udp_pkt_to_tuple,
421 .invert_tuple = udp_invert_tuple,
422 .print_tuple = udp_print_tuple,
423 .packet = udp_packet,
424 .get_timeouts = udp_get_timeouts,
426 .error = udplite_error,
427 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
428 .tuple_to_nlattr = nf_ct_port_tuple_to_nlattr,
429 .nlattr_to_tuple = nf_ct_port_nlattr_to_tuple,
430 .nlattr_tuple_size = nf_ct_port_nlattr_tuple_size,
431 .nla_policy = nf_ct_port_nla_policy,
433 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
435 .nlattr_to_obj = udp_timeout_nlattr_to_obj,
436 .obj_to_nlattr = udp_timeout_obj_to_nlattr,
437 .nlattr_max = CTA_TIMEOUT_UDP_MAX,
438 .obj_size = sizeof(unsigned int) * CTA_TIMEOUT_UDP_MAX,
439 .nla_policy = udp_timeout_nla_policy,
441 #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
442 .init_net = udp_init_net,
443 .get_net_proto = udp_get_net_proto,
445 EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_udplite6);