netfilter: xt_NFQUEUE: coalesce IPv4 and IPv6 hashing
[linux-3.10.git] / net / netfilter / nf_conntrack_proto_udplite.c
1 /* (C) 1999-2001 Paul `Rusty' Russell
2  * (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org>
3  * (C) 2007 Patrick McHardy <kaber@trash.net>
4  *
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.
8  */
9
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>
19
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
27 enum udplite_conntrack {
28         UDPLITE_CT_UNREPLIED,
29         UDPLITE_CT_REPLIED,
30         UDPLITE_CT_MAX
31 };
32
33 static unsigned int udplite_timeouts[UDPLITE_CT_MAX] = {
34         [UDPLITE_CT_UNREPLIED]  = 30*HZ,
35         [UDPLITE_CT_REPLIED]    = 180*HZ,
36 };
37
38 static int udplite_net_id __read_mostly;
39 struct udplite_net {
40         struct nf_proto_net pn;
41         unsigned int timeouts[UDPLITE_CT_MAX];
42 };
43
44 static inline struct udplite_net *udplite_pernet(struct net *net)
45 {
46         return net_generic(net, udplite_net_id);
47 }
48
49 static bool udplite_pkt_to_tuple(const struct sk_buff *skb,
50                                  unsigned int dataoff,
51                                  struct nf_conntrack_tuple *tuple)
52 {
53         const struct udphdr *hp;
54         struct udphdr _hdr;
55
56         hp = skb_header_pointer(skb, dataoff, sizeof(_hdr), &_hdr);
57         if (hp == NULL)
58                 return false;
59
60         tuple->src.u.udp.port = hp->source;
61         tuple->dst.u.udp.port = hp->dest;
62         return true;
63 }
64
65 static bool udplite_invert_tuple(struct nf_conntrack_tuple *tuple,
66                                  const struct nf_conntrack_tuple *orig)
67 {
68         tuple->src.u.udp.port = orig->dst.u.udp.port;
69         tuple->dst.u.udp.port = orig->src.u.udp.port;
70         return true;
71 }
72
73 /* Print out the per-protocol part of the tuple. */
74 static int udplite_print_tuple(struct seq_file *s,
75                                const struct nf_conntrack_tuple *tuple)
76 {
77         return seq_printf(s, "sport=%hu dport=%hu ",
78                           ntohs(tuple->src.u.udp.port),
79                           ntohs(tuple->dst.u.udp.port));
80 }
81
82 static unsigned int *udplite_get_timeouts(struct net *net)
83 {
84         return udplite_pernet(net)->timeouts;
85 }
86
87 /* Returns verdict for packet, and may modify conntracktype */
88 static int udplite_packet(struct nf_conn *ct,
89                           const struct sk_buff *skb,
90                           unsigned int dataoff,
91                           enum ip_conntrack_info ctinfo,
92                           u_int8_t pf,
93                           unsigned int hooknum,
94                           unsigned int *timeouts)
95 {
96         /* If we've seen traffic both ways, this is some kind of UDP
97            stream.  Extend timeout. */
98         if (test_bit(IPS_SEEN_REPLY_BIT, &ct->status)) {
99                 nf_ct_refresh_acct(ct, ctinfo, skb,
100                                    timeouts[UDPLITE_CT_REPLIED]);
101                 /* Also, more likely to be important, and not a probe */
102                 if (!test_and_set_bit(IPS_ASSURED_BIT, &ct->status))
103                         nf_conntrack_event_cache(IPCT_ASSURED, ct);
104         } else {
105                 nf_ct_refresh_acct(ct, ctinfo, skb,
106                                    timeouts[UDPLITE_CT_UNREPLIED]);
107         }
108         return NF_ACCEPT;
109 }
110
111 /* Called when a new connection for this protocol found. */
112 static bool udplite_new(struct nf_conn *ct, const struct sk_buff *skb,
113                         unsigned int dataoff, unsigned int *timeouts)
114 {
115         return true;
116 }
117
118 static int udplite_error(struct net *net, struct nf_conn *tmpl,
119                          struct sk_buff *skb,
120                          unsigned int dataoff,
121                          enum ip_conntrack_info *ctinfo,
122                          u_int8_t pf,
123                          unsigned int hooknum)
124 {
125         unsigned int udplen = skb->len - dataoff;
126         const struct udphdr *hdr;
127         struct udphdr _hdr;
128         unsigned int cscov;
129
130         /* Header is too small? */
131         hdr = skb_header_pointer(skb, dataoff, sizeof(_hdr), &_hdr);
132         if (hdr == NULL) {
133                 if (LOG_INVALID(net, IPPROTO_UDPLITE))
134                         nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
135                                       "nf_ct_udplite: short packet ");
136                 return -NF_ACCEPT;
137         }
138
139         cscov = ntohs(hdr->len);
140         if (cscov == 0)
141                 cscov = udplen;
142         else if (cscov < sizeof(*hdr) || cscov > udplen) {
143                 if (LOG_INVALID(net, IPPROTO_UDPLITE))
144                         nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
145                                 "nf_ct_udplite: invalid checksum coverage ");
146                 return -NF_ACCEPT;
147         }
148
149         /* UDPLITE mandates checksums */
150         if (!hdr->check) {
151                 if (LOG_INVALID(net, IPPROTO_UDPLITE))
152                         nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
153                                       "nf_ct_udplite: checksum missing ");
154                 return -NF_ACCEPT;
155         }
156
157         /* Checksum invalid? Ignore. */
158         if (net->ct.sysctl_checksum && hooknum == NF_INET_PRE_ROUTING &&
159             nf_checksum_partial(skb, hooknum, dataoff, cscov, IPPROTO_UDP,
160                                 pf)) {
161                 if (LOG_INVALID(net, IPPROTO_UDPLITE))
162                         nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
163                                       "nf_ct_udplite: bad UDPLite checksum ");
164                 return -NF_ACCEPT;
165         }
166
167         return NF_ACCEPT;
168 }
169
170 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
171
172 #include <linux/netfilter/nfnetlink.h>
173 #include <linux/netfilter/nfnetlink_cttimeout.h>
174
175 static int udplite_timeout_nlattr_to_obj(struct nlattr *tb[],
176                                          struct net *net, void *data)
177 {
178         unsigned int *timeouts = data;
179         struct udplite_net *un = udplite_pernet(net);
180
181         /* set default timeouts for UDPlite. */
182         timeouts[UDPLITE_CT_UNREPLIED] = un->timeouts[UDPLITE_CT_UNREPLIED];
183         timeouts[UDPLITE_CT_REPLIED] = un->timeouts[UDPLITE_CT_REPLIED];
184
185         if (tb[CTA_TIMEOUT_UDPLITE_UNREPLIED]) {
186                 timeouts[UDPLITE_CT_UNREPLIED] =
187                   ntohl(nla_get_be32(tb[CTA_TIMEOUT_UDPLITE_UNREPLIED])) * HZ;
188         }
189         if (tb[CTA_TIMEOUT_UDPLITE_REPLIED]) {
190                 timeouts[UDPLITE_CT_REPLIED] =
191                   ntohl(nla_get_be32(tb[CTA_TIMEOUT_UDPLITE_REPLIED])) * HZ;
192         }
193         return 0;
194 }
195
196 static int
197 udplite_timeout_obj_to_nlattr(struct sk_buff *skb, const void *data)
198 {
199         const unsigned int *timeouts = data;
200
201         if (nla_put_be32(skb, CTA_TIMEOUT_UDPLITE_UNREPLIED,
202                          htonl(timeouts[UDPLITE_CT_UNREPLIED] / HZ)) ||
203             nla_put_be32(skb, CTA_TIMEOUT_UDPLITE_REPLIED,
204                          htonl(timeouts[UDPLITE_CT_REPLIED] / HZ)))
205                 goto nla_put_failure;
206         return 0;
207
208 nla_put_failure:
209         return -ENOSPC;
210 }
211
212 static const struct nla_policy
213 udplite_timeout_nla_policy[CTA_TIMEOUT_UDPLITE_MAX+1] = {
214         [CTA_TIMEOUT_UDPLITE_UNREPLIED] = { .type = NLA_U32 },
215         [CTA_TIMEOUT_UDPLITE_REPLIED]   = { .type = NLA_U32 },
216 };
217 #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
218
219 #ifdef CONFIG_SYSCTL
220 static struct ctl_table udplite_sysctl_table[] = {
221         {
222                 .procname       = "nf_conntrack_udplite_timeout",
223                 .maxlen         = sizeof(unsigned int),
224                 .mode           = 0644,
225                 .proc_handler   = proc_dointvec_jiffies,
226         },
227         {
228                 .procname       = "nf_conntrack_udplite_timeout_stream",
229                 .maxlen         = sizeof(unsigned int),
230                 .mode           = 0644,
231                 .proc_handler   = proc_dointvec_jiffies,
232         },
233         { }
234 };
235 #endif /* CONFIG_SYSCTL */
236
237 static int udplite_kmemdup_sysctl_table(struct nf_proto_net *pn,
238                                         struct udplite_net *un)
239 {
240 #ifdef CONFIG_SYSCTL
241         if (pn->ctl_table)
242                 return 0;
243
244         pn->ctl_table = kmemdup(udplite_sysctl_table,
245                                 sizeof(udplite_sysctl_table),
246                                 GFP_KERNEL);
247         if (!pn->ctl_table)
248                 return -ENOMEM;
249
250         pn->ctl_table[0].data = &un->timeouts[UDPLITE_CT_UNREPLIED];
251         pn->ctl_table[1].data = &un->timeouts[UDPLITE_CT_REPLIED];
252 #endif
253         return 0;
254 }
255
256 static int udplite_init_net(struct net *net, u_int16_t proto)
257 {
258         struct udplite_net *un = udplite_pernet(net);
259         struct nf_proto_net *pn = &un->pn;
260
261         if (!pn->users) {
262                 int i;
263
264                 for (i = 0 ; i < UDPLITE_CT_MAX; i++)
265                         un->timeouts[i] = udplite_timeouts[i];
266         }
267
268         return udplite_kmemdup_sysctl_table(pn, un);
269 }
270
271 static struct nf_conntrack_l4proto nf_conntrack_l4proto_udplite4 __read_mostly =
272 {
273         .l3proto                = PF_INET,
274         .l4proto                = IPPROTO_UDPLITE,
275         .name                   = "udplite",
276         .pkt_to_tuple           = udplite_pkt_to_tuple,
277         .invert_tuple           = udplite_invert_tuple,
278         .print_tuple            = udplite_print_tuple,
279         .packet                 = udplite_packet,
280         .get_timeouts           = udplite_get_timeouts,
281         .new                    = udplite_new,
282         .error                  = udplite_error,
283 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
284         .tuple_to_nlattr        = nf_ct_port_tuple_to_nlattr,
285         .nlattr_tuple_size      = nf_ct_port_nlattr_tuple_size,
286         .nlattr_to_tuple        = nf_ct_port_nlattr_to_tuple,
287         .nla_policy             = nf_ct_port_nla_policy,
288 #endif
289 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
290         .ctnl_timeout           = {
291                 .nlattr_to_obj  = udplite_timeout_nlattr_to_obj,
292                 .obj_to_nlattr  = udplite_timeout_obj_to_nlattr,
293                 .nlattr_max     = CTA_TIMEOUT_UDPLITE_MAX,
294                 .obj_size       = sizeof(unsigned int) *
295                                         CTA_TIMEOUT_UDPLITE_MAX,
296                 .nla_policy     = udplite_timeout_nla_policy,
297         },
298 #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
299         .net_id                 = &udplite_net_id,
300         .init_net               = udplite_init_net,
301 };
302
303 static struct nf_conntrack_l4proto nf_conntrack_l4proto_udplite6 __read_mostly =
304 {
305         .l3proto                = PF_INET6,
306         .l4proto                = IPPROTO_UDPLITE,
307         .name                   = "udplite",
308         .pkt_to_tuple           = udplite_pkt_to_tuple,
309         .invert_tuple           = udplite_invert_tuple,
310         .print_tuple            = udplite_print_tuple,
311         .packet                 = udplite_packet,
312         .get_timeouts           = udplite_get_timeouts,
313         .new                    = udplite_new,
314         .error                  = udplite_error,
315 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
316         .tuple_to_nlattr        = nf_ct_port_tuple_to_nlattr,
317         .nlattr_tuple_size      = nf_ct_port_nlattr_tuple_size,
318         .nlattr_to_tuple        = nf_ct_port_nlattr_to_tuple,
319         .nla_policy             = nf_ct_port_nla_policy,
320 #endif
321 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
322         .ctnl_timeout           = {
323                 .nlattr_to_obj  = udplite_timeout_nlattr_to_obj,
324                 .obj_to_nlattr  = udplite_timeout_obj_to_nlattr,
325                 .nlattr_max     = CTA_TIMEOUT_UDPLITE_MAX,
326                 .obj_size       = sizeof(unsigned int) *
327                                         CTA_TIMEOUT_UDPLITE_MAX,
328                 .nla_policy     = udplite_timeout_nla_policy,
329         },
330 #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
331         .net_id                 = &udplite_net_id,
332         .init_net               = udplite_init_net,
333 };
334
335 static int udplite_net_init(struct net *net)
336 {
337         int ret = 0;
338
339         ret = nf_ct_l4proto_pernet_register(net, &nf_conntrack_l4proto_udplite4);
340         if (ret < 0) {
341                 pr_err("nf_conntrack_udplite4: pernet registration failed.\n");
342                 goto out;
343         }
344         ret = nf_ct_l4proto_pernet_register(net, &nf_conntrack_l4proto_udplite6);
345         if (ret < 0) {
346                 pr_err("nf_conntrack_udplite6: pernet registration failed.\n");
347                 goto cleanup_udplite4;
348         }
349         return 0;
350
351 cleanup_udplite4:
352         nf_ct_l4proto_pernet_unregister(net, &nf_conntrack_l4proto_udplite4);
353 out:
354         return ret;
355 }
356
357 static void udplite_net_exit(struct net *net)
358 {
359         nf_ct_l4proto_pernet_unregister(net, &nf_conntrack_l4proto_udplite6);
360         nf_ct_l4proto_pernet_unregister(net, &nf_conntrack_l4proto_udplite4);
361 }
362
363 static struct pernet_operations udplite_net_ops = {
364         .init = udplite_net_init,
365         .exit = udplite_net_exit,
366         .id   = &udplite_net_id,
367         .size = sizeof(struct udplite_net),
368 };
369
370 static int __init nf_conntrack_proto_udplite_init(void)
371 {
372         int ret;
373
374         ret = register_pernet_subsys(&udplite_net_ops);
375         if (ret < 0)
376                 goto out_pernet;
377
378         ret = nf_ct_l4proto_register(&nf_conntrack_l4proto_udplite4);
379         if (ret < 0)
380                 goto out_udplite4;
381
382         ret = nf_ct_l4proto_register(&nf_conntrack_l4proto_udplite6);
383         if (ret < 0)
384                 goto out_udplite6;
385
386         return 0;
387 out_udplite6:
388         nf_ct_l4proto_unregister(&nf_conntrack_l4proto_udplite4);
389 out_udplite4:
390         unregister_pernet_subsys(&udplite_net_ops);
391 out_pernet:
392         return ret;
393 }
394
395 static void __exit nf_conntrack_proto_udplite_exit(void)
396 {
397         nf_ct_l4proto_unregister(&nf_conntrack_l4proto_udplite6);
398         nf_ct_l4proto_unregister(&nf_conntrack_l4proto_udplite4);
399         unregister_pernet_subsys(&udplite_net_ops);
400 }
401
402 module_init(nf_conntrack_proto_udplite_init);
403 module_exit(nf_conntrack_proto_udplite_exit);
404
405 MODULE_LICENSE("GPL");