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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * UDP over IPv6
4 * Linux INET6 implementation
5 *
6 * Authors:
7 * Pedro Roque <roque@di.fc.ul.pt>
8 *
9 * Based on linux/ipv4/udp.c
10 *
11 * Fixes:
12 * Hideaki YOSHIFUJI : sin6_scope_id support
13 * YOSHIFUJI Hideaki @USAGI and: Support IPV6_V6ONLY socket option, which
14 * Alexey Kuznetsov allow both IPv4 and IPv6 sockets to bind
15 * a single port at the same time.
16 * Kazunori MIYAZAWA @USAGI: change process style to use ip6_append_data
17 * YOSHIFUJI Hideaki @USAGI: convert /proc/net/udp6 to seq_file.
18 */
19
20#include <linux/errno.h>
21#include <linux/types.h>
22#include <linux/socket.h>
23#include <linux/sockios.h>
24#include <linux/net.h>
25#include <linux/in6.h>
26#include <linux/netdevice.h>
27#include <linux/if_arp.h>
28#include <linux/ipv6.h>
29#include <linux/icmpv6.h>
30#include <linux/init.h>
31#include <linux/module.h>
32#include <linux/skbuff.h>
33#include <linux/slab.h>
34#include <linux/uaccess.h>
35#include <linux/indirect_call_wrapper.h>
36
37#include <net/addrconf.h>
38#include <net/ndisc.h>
39#include <net/protocol.h>
40#include <net/transp_v6.h>
41#include <net/ip6_route.h>
42#include <net/raw.h>
43#include <net/tcp_states.h>
44#include <net/ip6_checksum.h>
45#include <net/ip6_tunnel.h>
46#include <net/xfrm.h>
47#include <net/inet_hashtables.h>
48#include <net/inet6_hashtables.h>
49#include <net/busy_poll.h>
50#include <net/sock_reuseport.h>
51
52#include <linux/proc_fs.h>
53#include <linux/seq_file.h>
54#include <trace/events/skb.h>
55#include "udp_impl.h"
56
57static u32 udp6_ehashfn(const struct net *net,
58 const struct in6_addr *laddr,
59 const u16 lport,
60 const struct in6_addr *faddr,
61 const __be16 fport)
62{
63 static u32 udp6_ehash_secret __read_mostly;
64 static u32 udp_ipv6_hash_secret __read_mostly;
65
66 u32 lhash, fhash;
67
68 net_get_random_once(&udp6_ehash_secret,
69 sizeof(udp6_ehash_secret));
70 net_get_random_once(&udp_ipv6_hash_secret,
71 sizeof(udp_ipv6_hash_secret));
72
73 lhash = (__force u32)laddr->s6_addr32[3];
74 fhash = __ipv6_addr_jhash(faddr, udp_ipv6_hash_secret);
75
76 return __inet6_ehashfn(lhash, lport, fhash, fport,
77 udp_ipv6_hash_secret + net_hash_mix(net));
78}
79
80int udp_v6_get_port(struct sock *sk, unsigned short snum)
81{
82 unsigned int hash2_nulladdr =
83 ipv6_portaddr_hash(sock_net(sk), &in6addr_any, snum);
84 unsigned int hash2_partial =
85 ipv6_portaddr_hash(sock_net(sk), &sk->sk_v6_rcv_saddr, 0);
86
87 /* precompute partial secondary hash */
88 udp_sk(sk)->udp_portaddr_hash = hash2_partial;
89 return udp_lib_get_port(sk, snum, hash2_nulladdr);
90}
91
92void udp_v6_rehash(struct sock *sk)
93{
94 u16 new_hash = ipv6_portaddr_hash(sock_net(sk),
95 &sk->sk_v6_rcv_saddr,
96 inet_sk(sk)->inet_num);
97
98 udp_lib_rehash(sk, new_hash);
99}
100
101static int compute_score(struct sock *sk, struct net *net,
102 const struct in6_addr *saddr, __be16 sport,
103 const struct in6_addr *daddr, unsigned short hnum,
104 int dif, int sdif)
105{
106 int score;
107 struct inet_sock *inet;
108 bool dev_match;
109
110 if (!net_eq(sock_net(sk), net) ||
111 udp_sk(sk)->udp_port_hash != hnum ||
112 sk->sk_family != PF_INET6)
113 return -1;
114
115 if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
116 return -1;
117
118 score = 0;
119 inet = inet_sk(sk);
120
121 if (inet->inet_dport) {
122 if (inet->inet_dport != sport)
123 return -1;
124 score++;
125 }
126
127 if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
128 if (!ipv6_addr_equal(&sk->sk_v6_daddr, saddr))
129 return -1;
130 score++;
131 }
132
133 dev_match = udp_sk_bound_dev_eq(net, sk->sk_bound_dev_if, dif, sdif);
134 if (!dev_match)
135 return -1;
136 if (sk->sk_bound_dev_if)
137 score++;
138
139 if (READ_ONCE(sk->sk_incoming_cpu) == raw_smp_processor_id())
140 score++;
141
142 return score;
143}
144
145static struct sock *lookup_reuseport(struct net *net, struct sock *sk,
146 struct sk_buff *skb,
147 const struct in6_addr *saddr,
148 __be16 sport,
149 const struct in6_addr *daddr,
150 unsigned int hnum)
151{
152 struct sock *reuse_sk = NULL;
153 u32 hash;
154
155 if (sk->sk_reuseport && sk->sk_state != TCP_ESTABLISHED) {
156 hash = udp6_ehashfn(net, daddr, hnum, saddr, sport);
157 reuse_sk = reuseport_select_sock(sk, hash, skb,
158 sizeof(struct udphdr));
159 }
160 return reuse_sk;
161}
162
163/* called with rcu_read_lock() */
164static struct sock *udp6_lib_lookup2(struct net *net,
165 const struct in6_addr *saddr, __be16 sport,
166 const struct in6_addr *daddr, unsigned int hnum,
167 int dif, int sdif, struct udp_hslot *hslot2,
168 struct sk_buff *skb)
169{
170 struct sock *sk, *result;
171 int score, badness;
172
173 result = NULL;
174 badness = -1;
175 udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) {
176 score = compute_score(sk, net, saddr, sport,
177 daddr, hnum, dif, sdif);
178 if (score > badness) {
179 result = lookup_reuseport(net, sk, skb,
180 saddr, sport, daddr, hnum);
181 /* Fall back to scoring if group has connections */
182 if (result && !reuseport_has_conns(sk, false))
183 return result;
184
185 result = result ? : sk;
186 badness = score;
187 }
188 }
189 return result;
190}
191
192static inline struct sock *udp6_lookup_run_bpf(struct net *net,
193 struct udp_table *udptable,
194 struct sk_buff *skb,
195 const struct in6_addr *saddr,
196 __be16 sport,
197 const struct in6_addr *daddr,
198 u16 hnum)
199{
200 struct sock *sk, *reuse_sk;
201 bool no_reuseport;
202
203 if (udptable != &udp_table)
204 return NULL; /* only UDP is supported */
205
206 no_reuseport = bpf_sk_lookup_run_v6(net, IPPROTO_UDP,
207 saddr, sport, daddr, hnum, &sk);
208 if (no_reuseport || IS_ERR_OR_NULL(sk))
209 return sk;
210
211 reuse_sk = lookup_reuseport(net, sk, skb, saddr, sport, daddr, hnum);
212 if (reuse_sk)
213 sk = reuse_sk;
214 return sk;
215}
216
217/* rcu_read_lock() must be held */
218struct sock *__udp6_lib_lookup(struct net *net,
219 const struct in6_addr *saddr, __be16 sport,
220 const struct in6_addr *daddr, __be16 dport,
221 int dif, int sdif, struct udp_table *udptable,
222 struct sk_buff *skb)
223{
224 unsigned short hnum = ntohs(dport);
225 unsigned int hash2, slot2;
226 struct udp_hslot *hslot2;
227 struct sock *result, *sk;
228
229 hash2 = ipv6_portaddr_hash(net, daddr, hnum);
230 slot2 = hash2 & udptable->mask;
231 hslot2 = &udptable->hash2[slot2];
232
233 /* Lookup connected or non-wildcard sockets */
234 result = udp6_lib_lookup2(net, saddr, sport,
235 daddr, hnum, dif, sdif,
236 hslot2, skb);
237 if (!IS_ERR_OR_NULL(result) && result->sk_state == TCP_ESTABLISHED)
238 goto done;
239
240 /* Lookup redirect from BPF */
241 if (static_branch_unlikely(&bpf_sk_lookup_enabled)) {
242 sk = udp6_lookup_run_bpf(net, udptable, skb,
243 saddr, sport, daddr, hnum);
244 if (sk) {
245 result = sk;
246 goto done;
247 }
248 }
249
250 /* Got non-wildcard socket or error on first lookup */
251 if (result)
252 goto done;
253
254 /* Lookup wildcard sockets */
255 hash2 = ipv6_portaddr_hash(net, &in6addr_any, hnum);
256 slot2 = hash2 & udptable->mask;
257 hslot2 = &udptable->hash2[slot2];
258
259 result = udp6_lib_lookup2(net, saddr, sport,
260 &in6addr_any, hnum, dif, sdif,
261 hslot2, skb);
262done:
263 if (IS_ERR(result))
264 return NULL;
265 return result;
266}
267EXPORT_SYMBOL_GPL(__udp6_lib_lookup);
268
269static struct sock *__udp6_lib_lookup_skb(struct sk_buff *skb,
270 __be16 sport, __be16 dport,
271 struct udp_table *udptable)
272{
273 const struct ipv6hdr *iph = ipv6_hdr(skb);
274
275 return __udp6_lib_lookup(dev_net(skb->dev), &iph->saddr, sport,
276 &iph->daddr, dport, inet6_iif(skb),
277 inet6_sdif(skb), udptable, skb);
278}
279
280struct sock *udp6_lib_lookup_skb(const struct sk_buff *skb,
281 __be16 sport, __be16 dport)
282{
283 const struct ipv6hdr *iph = ipv6_hdr(skb);
284
285 return __udp6_lib_lookup(dev_net(skb->dev), &iph->saddr, sport,
286 &iph->daddr, dport, inet6_iif(skb),
287 inet6_sdif(skb), &udp_table, NULL);
288}
289
290/* Must be called under rcu_read_lock().
291 * Does increment socket refcount.
292 */
293#if IS_ENABLED(CONFIG_NF_TPROXY_IPV6) || IS_ENABLED(CONFIG_NF_SOCKET_IPV6)
294struct sock *udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport,
295 const struct in6_addr *daddr, __be16 dport, int dif)
296{
297 struct sock *sk;
298
299 sk = __udp6_lib_lookup(net, saddr, sport, daddr, dport,
300 dif, 0, &udp_table, NULL);
301 if (sk && !refcount_inc_not_zero(&sk->sk_refcnt))
302 sk = NULL;
303 return sk;
304}
305EXPORT_SYMBOL_GPL(udp6_lib_lookup);
306#endif
307
308/* do not use the scratch area len for jumbogram: their length execeeds the
309 * scratch area space; note that the IP6CB flags is still in the first
310 * cacheline, so checking for jumbograms is cheap
311 */
312static int udp6_skb_len(struct sk_buff *skb)
313{
314 return unlikely(inet6_is_jumbogram(skb)) ? skb->len : udp_skb_len(skb);
315}
316
317/*
318 * This should be easy, if there is something there we
319 * return it, otherwise we block.
320 */
321
322int udpv6_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
323 int noblock, int flags, int *addr_len)
324{
325 struct ipv6_pinfo *np = inet6_sk(sk);
326 struct inet_sock *inet = inet_sk(sk);
327 struct sk_buff *skb;
328 unsigned int ulen, copied;
329 int off, err, peeking = flags & MSG_PEEK;
330 int is_udplite = IS_UDPLITE(sk);
331 struct udp_mib __percpu *mib;
332 bool checksum_valid = false;
333 int is_udp4;
334
335 if (flags & MSG_ERRQUEUE)
336 return ipv6_recv_error(sk, msg, len, addr_len);
337
338 if (np->rxpmtu && np->rxopt.bits.rxpmtu)
339 return ipv6_recv_rxpmtu(sk, msg, len, addr_len);
340
341try_again:
342 off = sk_peek_offset(sk, flags);
343 skb = __skb_recv_udp(sk, flags, noblock, &off, &err);
344 if (!skb)
345 return err;
346
347 ulen = udp6_skb_len(skb);
348 copied = len;
349 if (copied > ulen - off)
350 copied = ulen - off;
351 else if (copied < ulen)
352 msg->msg_flags |= MSG_TRUNC;
353
354 is_udp4 = (skb->protocol == htons(ETH_P_IP));
355 mib = __UDPX_MIB(sk, is_udp4);
356
357 /*
358 * If checksum is needed at all, try to do it while copying the
359 * data. If the data is truncated, or if we only want a partial
360 * coverage checksum (UDP-Lite), do it before the copy.
361 */
362
363 if (copied < ulen || peeking ||
364 (is_udplite && UDP_SKB_CB(skb)->partial_cov)) {
365 checksum_valid = udp_skb_csum_unnecessary(skb) ||
366 !__udp_lib_checksum_complete(skb);
367 if (!checksum_valid)
368 goto csum_copy_err;
369 }
370
371 if (checksum_valid || udp_skb_csum_unnecessary(skb)) {
372 if (udp_skb_is_linear(skb))
373 err = copy_linear_skb(skb, copied, off, &msg->msg_iter);
374 else
375 err = skb_copy_datagram_msg(skb, off, msg, copied);
376 } else {
377 err = skb_copy_and_csum_datagram_msg(skb, off, msg);
378 if (err == -EINVAL)
379 goto csum_copy_err;
380 }
381 if (unlikely(err)) {
382 if (!peeking) {
383 atomic_inc(&sk->sk_drops);
384 SNMP_INC_STATS(mib, UDP_MIB_INERRORS);
385 }
386 kfree_skb(skb);
387 return err;
388 }
389 if (!peeking)
390 SNMP_INC_STATS(mib, UDP_MIB_INDATAGRAMS);
391
392 sock_recv_ts_and_drops(msg, sk, skb);
393
394 /* Copy the address. */
395 if (msg->msg_name) {
396 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
397 sin6->sin6_family = AF_INET6;
398 sin6->sin6_port = udp_hdr(skb)->source;
399 sin6->sin6_flowinfo = 0;
400
401 if (is_udp4) {
402 ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
403 &sin6->sin6_addr);
404 sin6->sin6_scope_id = 0;
405 } else {
406 sin6->sin6_addr = ipv6_hdr(skb)->saddr;
407 sin6->sin6_scope_id =
408 ipv6_iface_scope_id(&sin6->sin6_addr,
409 inet6_iif(skb));
410 }
411 *addr_len = sizeof(*sin6);
412
413 BPF_CGROUP_RUN_PROG_UDP6_RECVMSG_LOCK(sk,
414 (struct sockaddr *)sin6);
415 }
416
417 if (udp_sk(sk)->gro_enabled)
418 udp_cmsg_recv(msg, sk, skb);
419
420 if (np->rxopt.all)
421 ip6_datagram_recv_common_ctl(sk, msg, skb);
422
423 if (is_udp4) {
424 if (inet->cmsg_flags)
425 ip_cmsg_recv_offset(msg, sk, skb,
426 sizeof(struct udphdr), off);
427 } else {
428 if (np->rxopt.all)
429 ip6_datagram_recv_specific_ctl(sk, msg, skb);
430 }
431
432 err = copied;
433 if (flags & MSG_TRUNC)
434 err = ulen;
435
436 skb_consume_udp(sk, skb, peeking ? -err : err);
437 return err;
438
439csum_copy_err:
440 if (!__sk_queue_drop_skb(sk, &udp_sk(sk)->reader_queue, skb, flags,
441 udp_skb_destructor)) {
442 SNMP_INC_STATS(mib, UDP_MIB_CSUMERRORS);
443 SNMP_INC_STATS(mib, UDP_MIB_INERRORS);
444 }
445 kfree_skb(skb);
446
447 /* starting over for a new packet, but check if we need to yield */
448 cond_resched();
449 msg->msg_flags &= ~MSG_TRUNC;
450 goto try_again;
451}
452
453DEFINE_STATIC_KEY_FALSE(udpv6_encap_needed_key);
454void udpv6_encap_enable(void)
455{
456 static_branch_inc(&udpv6_encap_needed_key);
457}
458EXPORT_SYMBOL(udpv6_encap_enable);
459
460/* Handler for tunnels with arbitrary destination ports: no socket lookup, go
461 * through error handlers in encapsulations looking for a match.
462 */
463static int __udp6_lib_err_encap_no_sk(struct sk_buff *skb,
464 struct inet6_skb_parm *opt,
465 u8 type, u8 code, int offset, __be32 info)
466{
467 int i;
468
469 for (i = 0; i < MAX_IPTUN_ENCAP_OPS; i++) {
470 int (*handler)(struct sk_buff *skb, struct inet6_skb_parm *opt,
471 u8 type, u8 code, int offset, __be32 info);
472 const struct ip6_tnl_encap_ops *encap;
473
474 encap = rcu_dereference(ip6tun_encaps[i]);
475 if (!encap)
476 continue;
477 handler = encap->err_handler;
478 if (handler && !handler(skb, opt, type, code, offset, info))
479 return 0;
480 }
481
482 return -ENOENT;
483}
484
485/* Try to match ICMP errors to UDP tunnels by looking up a socket without
486 * reversing source and destination port: this will match tunnels that force the
487 * same destination port on both endpoints (e.g. VXLAN, GENEVE). Note that
488 * lwtunnels might actually break this assumption by being configured with
489 * different destination ports on endpoints, in this case we won't be able to
490 * trace ICMP messages back to them.
491 *
492 * If this doesn't match any socket, probe tunnels with arbitrary destination
493 * ports (e.g. FoU, GUE): there, the receiving socket is useless, as the port
494 * we've sent packets to won't necessarily match the local destination port.
495 *
496 * Then ask the tunnel implementation to match the error against a valid
497 * association.
498 *
499 * Return an error if we can't find a match, the socket if we need further
500 * processing, zero otherwise.
501 */
502static struct sock *__udp6_lib_err_encap(struct net *net,
503 const struct ipv6hdr *hdr, int offset,
504 struct udphdr *uh,
505 struct udp_table *udptable,
506 struct sock *sk,
507 struct sk_buff *skb,
508 struct inet6_skb_parm *opt,
509 u8 type, u8 code, __be32 info)
510{
511 int (*lookup)(struct sock *sk, struct sk_buff *skb);
512 int network_offset, transport_offset;
513 struct udp_sock *up;
514
515 network_offset = skb_network_offset(skb);
516 transport_offset = skb_transport_offset(skb);
517
518 /* Network header needs to point to the outer IPv6 header inside ICMP */
519 skb_reset_network_header(skb);
520
521 /* Transport header needs to point to the UDP header */
522 skb_set_transport_header(skb, offset);
523
524 if (sk) {
525 up = udp_sk(sk);
526
527 lookup = READ_ONCE(up->encap_err_lookup);
528 if (lookup && lookup(sk, skb))
529 sk = NULL;
530
531 goto out;
532 }
533
534 sk = __udp6_lib_lookup(net, &hdr->daddr, uh->source,
535 &hdr->saddr, uh->dest,
536 inet6_iif(skb), 0, udptable, skb);
537 if (sk) {
538 up = udp_sk(sk);
539
540 lookup = READ_ONCE(up->encap_err_lookup);
541 if (!lookup || lookup(sk, skb))
542 sk = NULL;
543 }
544
545out:
546 if (!sk) {
547 sk = ERR_PTR(__udp6_lib_err_encap_no_sk(skb, opt, type, code,
548 offset, info));
549 }
550
551 skb_set_transport_header(skb, transport_offset);
552 skb_set_network_header(skb, network_offset);
553
554 return sk;
555}
556
557int __udp6_lib_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
558 u8 type, u8 code, int offset, __be32 info,
559 struct udp_table *udptable)
560{
561 struct ipv6_pinfo *np;
562 const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data;
563 const struct in6_addr *saddr = &hdr->saddr;
564 const struct in6_addr *daddr = &hdr->daddr;
565 struct udphdr *uh = (struct udphdr *)(skb->data+offset);
566 bool tunnel = false;
567 struct sock *sk;
568 int harderr;
569 int err;
570 struct net *net = dev_net(skb->dev);
571
572 sk = __udp6_lib_lookup(net, daddr, uh->dest, saddr, uh->source,
573 inet6_iif(skb), inet6_sdif(skb), udptable, NULL);
574
575 if (!sk || udp_sk(sk)->encap_type) {
576 /* No socket for error: try tunnels before discarding */
577 if (static_branch_unlikely(&udpv6_encap_needed_key)) {
578 sk = __udp6_lib_err_encap(net, hdr, offset, uh,
579 udptable, sk, skb,
580 opt, type, code, info);
581 if (!sk)
582 return 0;
583 } else
584 sk = ERR_PTR(-ENOENT);
585
586 if (IS_ERR(sk)) {
587 __ICMP6_INC_STATS(net, __in6_dev_get(skb->dev),
588 ICMP6_MIB_INERRORS);
589 return PTR_ERR(sk);
590 }
591
592 tunnel = true;
593 }
594
595 harderr = icmpv6_err_convert(type, code, &err);
596 np = inet6_sk(sk);
597
598 if (type == ICMPV6_PKT_TOOBIG) {
599 if (!ip6_sk_accept_pmtu(sk))
600 goto out;
601 ip6_sk_update_pmtu(skb, sk, info);
602 if (np->pmtudisc != IPV6_PMTUDISC_DONT)
603 harderr = 1;
604 }
605 if (type == NDISC_REDIRECT) {
606 if (tunnel) {
607 ip6_redirect(skb, sock_net(sk), inet6_iif(skb),
608 sk->sk_mark, sk->sk_uid);
609 } else {
610 ip6_sk_redirect(skb, sk);
611 }
612 goto out;
613 }
614
615 /* Tunnels don't have an application socket: don't pass errors back */
616 if (tunnel)
617 goto out;
618
619 if (!np->recverr) {
620 if (!harderr || sk->sk_state != TCP_ESTABLISHED)
621 goto out;
622 } else {
623 ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1));
624 }
625
626 sk->sk_err = err;
627 sk_error_report(sk);
628out:
629 return 0;
630}
631
632static int __udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
633{
634 int rc;
635
636 if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
637 sock_rps_save_rxhash(sk, skb);
638 sk_mark_napi_id(sk, skb);
639 sk_incoming_cpu_update(sk);
640 } else {
641 sk_mark_napi_id_once(sk, skb);
642 }
643
644 rc = __udp_enqueue_schedule_skb(sk, skb);
645 if (rc < 0) {
646 int is_udplite = IS_UDPLITE(sk);
647
648 /* Note that an ENOMEM error is charged twice */
649 if (rc == -ENOMEM)
650 UDP6_INC_STATS(sock_net(sk),
651 UDP_MIB_RCVBUFERRORS, is_udplite);
652 else
653 UDP6_INC_STATS(sock_net(sk),
654 UDP_MIB_MEMERRORS, is_udplite);
655 UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
656 kfree_skb(skb);
657 return -1;
658 }
659
660 return 0;
661}
662
663static __inline__ int udpv6_err(struct sk_buff *skb,
664 struct inet6_skb_parm *opt, u8 type,
665 u8 code, int offset, __be32 info)
666{
667 return __udp6_lib_err(skb, opt, type, code, offset, info, &udp_table);
668}
669
670static int udpv6_queue_rcv_one_skb(struct sock *sk, struct sk_buff *skb)
671{
672 struct udp_sock *up = udp_sk(sk);
673 int is_udplite = IS_UDPLITE(sk);
674
675 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
676 goto drop;
677
678 if (static_branch_unlikely(&udpv6_encap_needed_key) && up->encap_type) {
679 int (*encap_rcv)(struct sock *sk, struct sk_buff *skb);
680
681 /*
682 * This is an encapsulation socket so pass the skb to
683 * the socket's udp_encap_rcv() hook. Otherwise, just
684 * fall through and pass this up the UDP socket.
685 * up->encap_rcv() returns the following value:
686 * =0 if skb was successfully passed to the encap
687 * handler or was discarded by it.
688 * >0 if skb should be passed on to UDP.
689 * <0 if skb should be resubmitted as proto -N
690 */
691
692 /* if we're overly short, let UDP handle it */
693 encap_rcv = READ_ONCE(up->encap_rcv);
694 if (encap_rcv) {
695 int ret;
696
697 /* Verify checksum before giving to encap */
698 if (udp_lib_checksum_complete(skb))
699 goto csum_error;
700
701 ret = encap_rcv(sk, skb);
702 if (ret <= 0) {
703 __UDP_INC_STATS(sock_net(sk),
704 UDP_MIB_INDATAGRAMS,
705 is_udplite);
706 return -ret;
707 }
708 }
709
710 /* FALLTHROUGH -- it's a UDP Packet */
711 }
712
713 /*
714 * UDP-Lite specific tests, ignored on UDP sockets (see net/ipv4/udp.c).
715 */
716 if ((up->pcflag & UDPLITE_RECV_CC) && UDP_SKB_CB(skb)->partial_cov) {
717
718 if (up->pcrlen == 0) { /* full coverage was set */
719 net_dbg_ratelimited("UDPLITE6: partial coverage %d while full coverage %d requested\n",
720 UDP_SKB_CB(skb)->cscov, skb->len);
721 goto drop;
722 }
723 if (UDP_SKB_CB(skb)->cscov < up->pcrlen) {
724 net_dbg_ratelimited("UDPLITE6: coverage %d too small, need min %d\n",
725 UDP_SKB_CB(skb)->cscov, up->pcrlen);
726 goto drop;
727 }
728 }
729
730 prefetch(&sk->sk_rmem_alloc);
731 if (rcu_access_pointer(sk->sk_filter) &&
732 udp_lib_checksum_complete(skb))
733 goto csum_error;
734
735 if (sk_filter_trim_cap(sk, skb, sizeof(struct udphdr)))
736 goto drop;
737
738 udp_csum_pull_header(skb);
739
740 skb_dst_drop(skb);
741
742 return __udpv6_queue_rcv_skb(sk, skb);
743
744csum_error:
745 __UDP6_INC_STATS(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite);
746drop:
747 __UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
748 atomic_inc(&sk->sk_drops);
749 kfree_skb(skb);
750 return -1;
751}
752
753static int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
754{
755 struct sk_buff *next, *segs;
756 int ret;
757
758 if (likely(!udp_unexpected_gso(sk, skb)))
759 return udpv6_queue_rcv_one_skb(sk, skb);
760
761 __skb_push(skb, -skb_mac_offset(skb));
762 segs = udp_rcv_segment(sk, skb, false);
763 skb_list_walk_safe(segs, skb, next) {
764 __skb_pull(skb, skb_transport_offset(skb));
765
766 udp_post_segment_fix_csum(skb);
767 ret = udpv6_queue_rcv_one_skb(sk, skb);
768 if (ret > 0)
769 ip6_protocol_deliver_rcu(dev_net(skb->dev), skb, ret,
770 true);
771 }
772 return 0;
773}
774
775static bool __udp_v6_is_mcast_sock(struct net *net, struct sock *sk,
776 __be16 loc_port, const struct in6_addr *loc_addr,
777 __be16 rmt_port, const struct in6_addr *rmt_addr,
778 int dif, int sdif, unsigned short hnum)
779{
780 struct inet_sock *inet = inet_sk(sk);
781
782 if (!net_eq(sock_net(sk), net))
783 return false;
784
785 if (udp_sk(sk)->udp_port_hash != hnum ||
786 sk->sk_family != PF_INET6 ||
787 (inet->inet_dport && inet->inet_dport != rmt_port) ||
788 (!ipv6_addr_any(&sk->sk_v6_daddr) &&
789 !ipv6_addr_equal(&sk->sk_v6_daddr, rmt_addr)) ||
790 !udp_sk_bound_dev_eq(net, sk->sk_bound_dev_if, dif, sdif) ||
791 (!ipv6_addr_any(&sk->sk_v6_rcv_saddr) &&
792 !ipv6_addr_equal(&sk->sk_v6_rcv_saddr, loc_addr)))
793 return false;
794 if (!inet6_mc_check(sk, loc_addr, rmt_addr))
795 return false;
796 return true;
797}
798
799static void udp6_csum_zero_error(struct sk_buff *skb)
800{
801 /* RFC 2460 section 8.1 says that we SHOULD log
802 * this error. Well, it is reasonable.
803 */
804 net_dbg_ratelimited("IPv6: udp checksum is 0 for [%pI6c]:%u->[%pI6c]:%u\n",
805 &ipv6_hdr(skb)->saddr, ntohs(udp_hdr(skb)->source),
806 &ipv6_hdr(skb)->daddr, ntohs(udp_hdr(skb)->dest));
807}
808
809/*
810 * Note: called only from the BH handler context,
811 * so we don't need to lock the hashes.
812 */
813static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
814 const struct in6_addr *saddr, const struct in6_addr *daddr,
815 struct udp_table *udptable, int proto)
816{
817 struct sock *sk, *first = NULL;
818 const struct udphdr *uh = udp_hdr(skb);
819 unsigned short hnum = ntohs(uh->dest);
820 struct udp_hslot *hslot = udp_hashslot(udptable, net, hnum);
821 unsigned int offset = offsetof(typeof(*sk), sk_node);
822 unsigned int hash2 = 0, hash2_any = 0, use_hash2 = (hslot->count > 10);
823 int dif = inet6_iif(skb);
824 int sdif = inet6_sdif(skb);
825 struct hlist_node *node;
826 struct sk_buff *nskb;
827
828 if (use_hash2) {
829 hash2_any = ipv6_portaddr_hash(net, &in6addr_any, hnum) &
830 udptable->mask;
831 hash2 = ipv6_portaddr_hash(net, daddr, hnum) & udptable->mask;
832start_lookup:
833 hslot = &udptable->hash2[hash2];
834 offset = offsetof(typeof(*sk), __sk_common.skc_portaddr_node);
835 }
836
837 sk_for_each_entry_offset_rcu(sk, node, &hslot->head, offset) {
838 if (!__udp_v6_is_mcast_sock(net, sk, uh->dest, daddr,
839 uh->source, saddr, dif, sdif,
840 hnum))
841 continue;
842 /* If zero checksum and no_check is not on for
843 * the socket then skip it.
844 */
845 if (!uh->check && !udp_sk(sk)->no_check6_rx)
846 continue;
847 if (!first) {
848 first = sk;
849 continue;
850 }
851 nskb = skb_clone(skb, GFP_ATOMIC);
852 if (unlikely(!nskb)) {
853 atomic_inc(&sk->sk_drops);
854 __UDP6_INC_STATS(net, UDP_MIB_RCVBUFERRORS,
855 IS_UDPLITE(sk));
856 __UDP6_INC_STATS(net, UDP_MIB_INERRORS,
857 IS_UDPLITE(sk));
858 continue;
859 }
860
861 if (udpv6_queue_rcv_skb(sk, nskb) > 0)
862 consume_skb(nskb);
863 }
864
865 /* Also lookup *:port if we are using hash2 and haven't done so yet. */
866 if (use_hash2 && hash2 != hash2_any) {
867 hash2 = hash2_any;
868 goto start_lookup;
869 }
870
871 if (first) {
872 if (udpv6_queue_rcv_skb(first, skb) > 0)
873 consume_skb(skb);
874 } else {
875 kfree_skb(skb);
876 __UDP6_INC_STATS(net, UDP_MIB_IGNOREDMULTI,
877 proto == IPPROTO_UDPLITE);
878 }
879 return 0;
880}
881
882static void udp6_sk_rx_dst_set(struct sock *sk, struct dst_entry *dst)
883{
884 if (udp_sk_rx_dst_set(sk, dst)) {
885 const struct rt6_info *rt = (const struct rt6_info *)dst;
886
887 inet6_sk(sk)->rx_dst_cookie = rt6_get_cookie(rt);
888 }
889}
890
891/* wrapper for udp_queue_rcv_skb tacking care of csum conversion and
892 * return code conversion for ip layer consumption
893 */
894static int udp6_unicast_rcv_skb(struct sock *sk, struct sk_buff *skb,
895 struct udphdr *uh)
896{
897 int ret;
898
899 if (inet_get_convert_csum(sk) && uh->check && !IS_UDPLITE(sk))
900 skb_checksum_try_convert(skb, IPPROTO_UDP, ip6_compute_pseudo);
901
902 ret = udpv6_queue_rcv_skb(sk, skb);
903
904 /* a return value > 0 means to resubmit the input */
905 if (ret > 0)
906 return ret;
907 return 0;
908}
909
910int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
911 int proto)
912{
913 const struct in6_addr *saddr, *daddr;
914 struct net *net = dev_net(skb->dev);
915 struct udphdr *uh;
916 struct sock *sk;
917 bool refcounted;
918 u32 ulen = 0;
919
920 if (!pskb_may_pull(skb, sizeof(struct udphdr)))
921 goto discard;
922
923 saddr = &ipv6_hdr(skb)->saddr;
924 daddr = &ipv6_hdr(skb)->daddr;
925 uh = udp_hdr(skb);
926
927 ulen = ntohs(uh->len);
928 if (ulen > skb->len)
929 goto short_packet;
930
931 if (proto == IPPROTO_UDP) {
932 /* UDP validates ulen. */
933
934 /* Check for jumbo payload */
935 if (ulen == 0)
936 ulen = skb->len;
937
938 if (ulen < sizeof(*uh))
939 goto short_packet;
940
941 if (ulen < skb->len) {
942 if (pskb_trim_rcsum(skb, ulen))
943 goto short_packet;
944 saddr = &ipv6_hdr(skb)->saddr;
945 daddr = &ipv6_hdr(skb)->daddr;
946 uh = udp_hdr(skb);
947 }
948 }
949
950 if (udp6_csum_init(skb, uh, proto))
951 goto csum_error;
952
953 /* Check if the socket is already available, e.g. due to early demux */
954 sk = skb_steal_sock(skb, &refcounted);
955 if (sk) {
956 struct dst_entry *dst = skb_dst(skb);
957 int ret;
958
959 if (unlikely(sk->sk_rx_dst != dst))
960 udp6_sk_rx_dst_set(sk, dst);
961
962 if (!uh->check && !udp_sk(sk)->no_check6_rx) {
963 if (refcounted)
964 sock_put(sk);
965 goto report_csum_error;
966 }
967
968 ret = udp6_unicast_rcv_skb(sk, skb, uh);
969 if (refcounted)
970 sock_put(sk);
971 return ret;
972 }
973
974 /*
975 * Multicast receive code
976 */
977 if (ipv6_addr_is_multicast(daddr))
978 return __udp6_lib_mcast_deliver(net, skb,
979 saddr, daddr, udptable, proto);
980
981 /* Unicast */
982 sk = __udp6_lib_lookup_skb(skb, uh->source, uh->dest, udptable);
983 if (sk) {
984 if (!uh->check && !udp_sk(sk)->no_check6_rx)
985 goto report_csum_error;
986 return udp6_unicast_rcv_skb(sk, skb, uh);
987 }
988
989 if (!uh->check)
990 goto report_csum_error;
991
992 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
993 goto discard;
994
995 if (udp_lib_checksum_complete(skb))
996 goto csum_error;
997
998 __UDP6_INC_STATS(net, UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE);
999 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
1000
1001 kfree_skb(skb);
1002 return 0;
1003
1004short_packet:
1005 net_dbg_ratelimited("UDP%sv6: short packet: From [%pI6c]:%u %d/%d to [%pI6c]:%u\n",
1006 proto == IPPROTO_UDPLITE ? "-Lite" : "",
1007 saddr, ntohs(uh->source),
1008 ulen, skb->len,
1009 daddr, ntohs(uh->dest));
1010 goto discard;
1011
1012report_csum_error:
1013 udp6_csum_zero_error(skb);
1014csum_error:
1015 __UDP6_INC_STATS(net, UDP_MIB_CSUMERRORS, proto == IPPROTO_UDPLITE);
1016discard:
1017 __UDP6_INC_STATS(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE);
1018 kfree_skb(skb);
1019 return 0;
1020}
1021
1022
1023static struct sock *__udp6_lib_demux_lookup(struct net *net,
1024 __be16 loc_port, const struct in6_addr *loc_addr,
1025 __be16 rmt_port, const struct in6_addr *rmt_addr,
1026 int dif, int sdif)
1027{
1028 unsigned short hnum = ntohs(loc_port);
1029 unsigned int hash2 = ipv6_portaddr_hash(net, loc_addr, hnum);
1030 unsigned int slot2 = hash2 & udp_table.mask;
1031 struct udp_hslot *hslot2 = &udp_table.hash2[slot2];
1032 const __portpair ports = INET_COMBINED_PORTS(rmt_port, hnum);
1033 struct sock *sk;
1034
1035 udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) {
1036 if (sk->sk_state == TCP_ESTABLISHED &&
1037 INET6_MATCH(sk, net, rmt_addr, loc_addr, ports, dif, sdif))
1038 return sk;
1039 /* Only check first socket in chain */
1040 break;
1041 }
1042 return NULL;
1043}
1044
1045INDIRECT_CALLABLE_SCOPE void udp_v6_early_demux(struct sk_buff *skb)
1046{
1047 struct net *net = dev_net(skb->dev);
1048 const struct udphdr *uh;
1049 struct sock *sk;
1050 struct dst_entry *dst;
1051 int dif = skb->dev->ifindex;
1052 int sdif = inet6_sdif(skb);
1053
1054 if (!pskb_may_pull(skb, skb_transport_offset(skb) +
1055 sizeof(struct udphdr)))
1056 return;
1057
1058 uh = udp_hdr(skb);
1059
1060 if (skb->pkt_type == PACKET_HOST)
1061 sk = __udp6_lib_demux_lookup(net, uh->dest,
1062 &ipv6_hdr(skb)->daddr,
1063 uh->source, &ipv6_hdr(skb)->saddr,
1064 dif, sdif);
1065 else
1066 return;
1067
1068 if (!sk || !refcount_inc_not_zero(&sk->sk_refcnt))
1069 return;
1070
1071 skb->sk = sk;
1072 skb->destructor = sock_efree;
1073 dst = READ_ONCE(sk->sk_rx_dst);
1074
1075 if (dst)
1076 dst = dst_check(dst, inet6_sk(sk)->rx_dst_cookie);
1077 if (dst) {
1078 /* set noref for now.
1079 * any place which wants to hold dst has to call
1080 * dst_hold_safe()
1081 */
1082 skb_dst_set_noref(skb, dst);
1083 }
1084}
1085
1086INDIRECT_CALLABLE_SCOPE int udpv6_rcv(struct sk_buff *skb)
1087{
1088 return __udp6_lib_rcv(skb, &udp_table, IPPROTO_UDP);
1089}
1090
1091/*
1092 * Throw away all pending data and cancel the corking. Socket is locked.
1093 */
1094static void udp_v6_flush_pending_frames(struct sock *sk)
1095{
1096 struct udp_sock *up = udp_sk(sk);
1097
1098 if (up->pending == AF_INET)
1099 udp_flush_pending_frames(sk);
1100 else if (up->pending) {
1101 up->len = 0;
1102 up->pending = 0;
1103 ip6_flush_pending_frames(sk);
1104 }
1105}
1106
1107static int udpv6_pre_connect(struct sock *sk, struct sockaddr *uaddr,
1108 int addr_len)
1109{
1110 if (addr_len < offsetofend(struct sockaddr, sa_family))
1111 return -EINVAL;
1112 /* The following checks are replicated from __ip6_datagram_connect()
1113 * and intended to prevent BPF program called below from accessing
1114 * bytes that are out of the bound specified by user in addr_len.
1115 */
1116 if (uaddr->sa_family == AF_INET) {
1117 if (__ipv6_only_sock(sk))
1118 return -EAFNOSUPPORT;
1119 return udp_pre_connect(sk, uaddr, addr_len);
1120 }
1121
1122 if (addr_len < SIN6_LEN_RFC2133)
1123 return -EINVAL;
1124
1125 return BPF_CGROUP_RUN_PROG_INET6_CONNECT_LOCK(sk, uaddr);
1126}
1127
1128/**
1129 * udp6_hwcsum_outgoing - handle outgoing HW checksumming
1130 * @sk: socket we are sending on
1131 * @skb: sk_buff containing the filled-in UDP header
1132 * (checksum field must be zeroed out)
1133 * @saddr: source address
1134 * @daddr: destination address
1135 * @len: length of packet
1136 */
1137static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb,
1138 const struct in6_addr *saddr,
1139 const struct in6_addr *daddr, int len)
1140{
1141 unsigned int offset;
1142 struct udphdr *uh = udp_hdr(skb);
1143 struct sk_buff *frags = skb_shinfo(skb)->frag_list;
1144 __wsum csum = 0;
1145
1146 if (!frags) {
1147 /* Only one fragment on the socket. */
1148 skb->csum_start = skb_transport_header(skb) - skb->head;
1149 skb->csum_offset = offsetof(struct udphdr, check);
1150 uh->check = ~csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 0);
1151 } else {
1152 /*
1153 * HW-checksum won't work as there are two or more
1154 * fragments on the socket so that all csums of sk_buffs
1155 * should be together
1156 */
1157 offset = skb_transport_offset(skb);
1158 skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
1159 csum = skb->csum;
1160
1161 skb->ip_summed = CHECKSUM_NONE;
1162
1163 do {
1164 csum = csum_add(csum, frags->csum);
1165 } while ((frags = frags->next));
1166
1167 uh->check = csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP,
1168 csum);
1169 if (uh->check == 0)
1170 uh->check = CSUM_MANGLED_0;
1171 }
1172}
1173
1174/*
1175 * Sending
1176 */
1177
1178static int udp_v6_send_skb(struct sk_buff *skb, struct flowi6 *fl6,
1179 struct inet_cork *cork)
1180{
1181 struct sock *sk = skb->sk;
1182 struct udphdr *uh;
1183 int err = 0;
1184 int is_udplite = IS_UDPLITE(sk);
1185 __wsum csum = 0;
1186 int offset = skb_transport_offset(skb);
1187 int len = skb->len - offset;
1188 int datalen = len - sizeof(*uh);
1189
1190 /*
1191 * Create a UDP header
1192 */
1193 uh = udp_hdr(skb);
1194 uh->source = fl6->fl6_sport;
1195 uh->dest = fl6->fl6_dport;
1196 uh->len = htons(len);
1197 uh->check = 0;
1198
1199 if (cork->gso_size) {
1200 const int hlen = skb_network_header_len(skb) +
1201 sizeof(struct udphdr);
1202
1203 if (hlen + cork->gso_size > cork->fragsize) {
1204 kfree_skb(skb);
1205 return -EINVAL;
1206 }
1207 if (skb->len > cork->gso_size * UDP_MAX_SEGMENTS) {
1208 kfree_skb(skb);
1209 return -EINVAL;
1210 }
1211 if (udp_sk(sk)->no_check6_tx) {
1212 kfree_skb(skb);
1213 return -EINVAL;
1214 }
1215 if (skb->ip_summed != CHECKSUM_PARTIAL || is_udplite ||
1216 dst_xfrm(skb_dst(skb))) {
1217 kfree_skb(skb);
1218 return -EIO;
1219 }
1220
1221 if (datalen > cork->gso_size) {
1222 skb_shinfo(skb)->gso_size = cork->gso_size;
1223 skb_shinfo(skb)->gso_type = SKB_GSO_UDP_L4;
1224 skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(datalen,
1225 cork->gso_size);
1226 }
1227 goto csum_partial;
1228 }
1229
1230 if (is_udplite)
1231 csum = udplite_csum(skb);
1232 else if (udp_sk(sk)->no_check6_tx) { /* UDP csum disabled */
1233 skb->ip_summed = CHECKSUM_NONE;
1234 goto send;
1235 } else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */
1236csum_partial:
1237 udp6_hwcsum_outgoing(sk, skb, &fl6->saddr, &fl6->daddr, len);
1238 goto send;
1239 } else
1240 csum = udp_csum(skb);
1241
1242 /* add protocol-dependent pseudo-header */
1243 uh->check = csum_ipv6_magic(&fl6->saddr, &fl6->daddr,
1244 len, fl6->flowi6_proto, csum);
1245 if (uh->check == 0)
1246 uh->check = CSUM_MANGLED_0;
1247
1248send:
1249 err = ip6_send_skb(skb);
1250 if (err) {
1251 if (err == -ENOBUFS && !inet6_sk(sk)->recverr) {
1252 UDP6_INC_STATS(sock_net(sk),
1253 UDP_MIB_SNDBUFERRORS, is_udplite);
1254 err = 0;
1255 }
1256 } else {
1257 UDP6_INC_STATS(sock_net(sk),
1258 UDP_MIB_OUTDATAGRAMS, is_udplite);
1259 }
1260 return err;
1261}
1262
1263static int udp_v6_push_pending_frames(struct sock *sk)
1264{
1265 struct sk_buff *skb;
1266 struct udp_sock *up = udp_sk(sk);
1267 struct flowi6 fl6;
1268 int err = 0;
1269
1270 if (up->pending == AF_INET)
1271 return udp_push_pending_frames(sk);
1272
1273 /* ip6_finish_skb will release the cork, so make a copy of
1274 * fl6 here.
1275 */
1276 fl6 = inet_sk(sk)->cork.fl.u.ip6;
1277
1278 skb = ip6_finish_skb(sk);
1279 if (!skb)
1280 goto out;
1281
1282 err = udp_v6_send_skb(skb, &fl6, &inet_sk(sk)->cork.base);
1283
1284out:
1285 up->len = 0;
1286 up->pending = 0;
1287 return err;
1288}
1289
1290int udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
1291{
1292 struct ipv6_txoptions opt_space;
1293 struct udp_sock *up = udp_sk(sk);
1294 struct inet_sock *inet = inet_sk(sk);
1295 struct ipv6_pinfo *np = inet6_sk(sk);
1296 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
1297 struct in6_addr *daddr, *final_p, final;
1298 struct ipv6_txoptions *opt = NULL;
1299 struct ipv6_txoptions *opt_to_free = NULL;
1300 struct ip6_flowlabel *flowlabel = NULL;
1301 struct flowi6 fl6;
1302 struct dst_entry *dst;
1303 struct ipcm6_cookie ipc6;
1304 int addr_len = msg->msg_namelen;
1305 bool connected = false;
1306 int ulen = len;
1307 int corkreq = READ_ONCE(up->corkflag) || msg->msg_flags&MSG_MORE;
1308 int err;
1309 int is_udplite = IS_UDPLITE(sk);
1310 int (*getfrag)(void *, char *, int, int, int, struct sk_buff *);
1311
1312 ipcm6_init(&ipc6);
1313 ipc6.gso_size = READ_ONCE(up->gso_size);
1314 ipc6.sockc.tsflags = sk->sk_tsflags;
1315 ipc6.sockc.mark = sk->sk_mark;
1316
1317 /* destination address check */
1318 if (sin6) {
1319 if (addr_len < offsetof(struct sockaddr, sa_data))
1320 return -EINVAL;
1321
1322 switch (sin6->sin6_family) {
1323 case AF_INET6:
1324 if (addr_len < SIN6_LEN_RFC2133)
1325 return -EINVAL;
1326 daddr = &sin6->sin6_addr;
1327 if (ipv6_addr_any(daddr) &&
1328 ipv6_addr_v4mapped(&np->saddr))
1329 ipv6_addr_set_v4mapped(htonl(INADDR_LOOPBACK),
1330 daddr);
1331 break;
1332 case AF_INET:
1333 goto do_udp_sendmsg;
1334 case AF_UNSPEC:
1335 msg->msg_name = sin6 = NULL;
1336 msg->msg_namelen = addr_len = 0;
1337 daddr = NULL;
1338 break;
1339 default:
1340 return -EINVAL;
1341 }
1342 } else if (!up->pending) {
1343 if (sk->sk_state != TCP_ESTABLISHED)
1344 return -EDESTADDRREQ;
1345 daddr = &sk->sk_v6_daddr;
1346 } else
1347 daddr = NULL;
1348
1349 if (daddr) {
1350 if (ipv6_addr_v4mapped(daddr)) {
1351 struct sockaddr_in sin;
1352 sin.sin_family = AF_INET;
1353 sin.sin_port = sin6 ? sin6->sin6_port : inet->inet_dport;
1354 sin.sin_addr.s_addr = daddr->s6_addr32[3];
1355 msg->msg_name = &sin;
1356 msg->msg_namelen = sizeof(sin);
1357do_udp_sendmsg:
1358 if (__ipv6_only_sock(sk))
1359 return -ENETUNREACH;
1360 return udp_sendmsg(sk, msg, len);
1361 }
1362 }
1363
1364 if (up->pending == AF_INET)
1365 return udp_sendmsg(sk, msg, len);
1366
1367 /* Rough check on arithmetic overflow,
1368 better check is made in ip6_append_data().
1369 */
1370 if (len > INT_MAX - sizeof(struct udphdr))
1371 return -EMSGSIZE;
1372
1373 getfrag = is_udplite ? udplite_getfrag : ip_generic_getfrag;
1374 if (up->pending) {
1375 /*
1376 * There are pending frames.
1377 * The socket lock must be held while it's corked.
1378 */
1379 lock_sock(sk);
1380 if (likely(up->pending)) {
1381 if (unlikely(up->pending != AF_INET6)) {
1382 release_sock(sk);
1383 return -EAFNOSUPPORT;
1384 }
1385 dst = NULL;
1386 goto do_append_data;
1387 }
1388 release_sock(sk);
1389 }
1390 ulen += sizeof(struct udphdr);
1391
1392 memset(&fl6, 0, sizeof(fl6));
1393
1394 if (sin6) {
1395 if (sin6->sin6_port == 0)
1396 return -EINVAL;
1397
1398 fl6.fl6_dport = sin6->sin6_port;
1399 daddr = &sin6->sin6_addr;
1400
1401 if (np->sndflow) {
1402 fl6.flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK;
1403 if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) {
1404 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1405 if (IS_ERR(flowlabel))
1406 return -EINVAL;
1407 }
1408 }
1409
1410 /*
1411 * Otherwise it will be difficult to maintain
1412 * sk->sk_dst_cache.
1413 */
1414 if (sk->sk_state == TCP_ESTABLISHED &&
1415 ipv6_addr_equal(daddr, &sk->sk_v6_daddr))
1416 daddr = &sk->sk_v6_daddr;
1417
1418 if (addr_len >= sizeof(struct sockaddr_in6) &&
1419 sin6->sin6_scope_id &&
1420 __ipv6_addr_needs_scope_id(__ipv6_addr_type(daddr)))
1421 fl6.flowi6_oif = sin6->sin6_scope_id;
1422 } else {
1423 if (sk->sk_state != TCP_ESTABLISHED)
1424 return -EDESTADDRREQ;
1425
1426 fl6.fl6_dport = inet->inet_dport;
1427 daddr = &sk->sk_v6_daddr;
1428 fl6.flowlabel = np->flow_label;
1429 connected = true;
1430 }
1431
1432 if (!fl6.flowi6_oif)
1433 fl6.flowi6_oif = sk->sk_bound_dev_if;
1434
1435 if (!fl6.flowi6_oif)
1436 fl6.flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;
1437
1438 fl6.flowi6_mark = ipc6.sockc.mark;
1439 fl6.flowi6_uid = sk->sk_uid;
1440
1441 if (msg->msg_controllen) {
1442 opt = &opt_space;
1443 memset(opt, 0, sizeof(struct ipv6_txoptions));
1444 opt->tot_len = sizeof(*opt);
1445 ipc6.opt = opt;
1446
1447 err = udp_cmsg_send(sk, msg, &ipc6.gso_size);
1448 if (err > 0)
1449 err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, &fl6,
1450 &ipc6);
1451 if (err < 0) {
1452 fl6_sock_release(flowlabel);
1453 return err;
1454 }
1455 if ((fl6.flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) {
1456 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1457 if (IS_ERR(flowlabel))
1458 return -EINVAL;
1459 }
1460 if (!(opt->opt_nflen|opt->opt_flen))
1461 opt = NULL;
1462 connected = false;
1463 }
1464 if (!opt) {
1465 opt = txopt_get(np);
1466 opt_to_free = opt;
1467 }
1468 if (flowlabel)
1469 opt = fl6_merge_options(&opt_space, flowlabel, opt);
1470 opt = ipv6_fixup_options(&opt_space, opt);
1471 ipc6.opt = opt;
1472
1473 fl6.flowi6_proto = sk->sk_protocol;
1474 fl6.daddr = *daddr;
1475 if (ipv6_addr_any(&fl6.saddr) && !ipv6_addr_any(&np->saddr))
1476 fl6.saddr = np->saddr;
1477 fl6.fl6_sport = inet->inet_sport;
1478
1479 if (cgroup_bpf_enabled(BPF_CGROUP_UDP6_SENDMSG) && !connected) {
1480 err = BPF_CGROUP_RUN_PROG_UDP6_SENDMSG_LOCK(sk,
1481 (struct sockaddr *)sin6, &fl6.saddr);
1482 if (err)
1483 goto out_no_dst;
1484 if (sin6) {
1485 if (ipv6_addr_v4mapped(&sin6->sin6_addr)) {
1486 /* BPF program rewrote IPv6-only by IPv4-mapped
1487 * IPv6. It's currently unsupported.
1488 */
1489 err = -ENOTSUPP;
1490 goto out_no_dst;
1491 }
1492 if (sin6->sin6_port == 0) {
1493 /* BPF program set invalid port. Reject it. */
1494 err = -EINVAL;
1495 goto out_no_dst;
1496 }
1497 fl6.fl6_dport = sin6->sin6_port;
1498 fl6.daddr = sin6->sin6_addr;
1499 }
1500 }
1501
1502 if (ipv6_addr_any(&fl6.daddr))
1503 fl6.daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */
1504
1505 final_p = fl6_update_dst(&fl6, opt, &final);
1506 if (final_p)
1507 connected = false;
1508
1509 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr)) {
1510 fl6.flowi6_oif = np->mcast_oif;
1511 connected = false;
1512 } else if (!fl6.flowi6_oif)
1513 fl6.flowi6_oif = np->ucast_oif;
1514
1515 security_sk_classify_flow(sk, flowi6_to_flowi_common(&fl6));
1516
1517 if (ipc6.tclass < 0)
1518 ipc6.tclass = np->tclass;
1519
1520 fl6.flowlabel = ip6_make_flowinfo(ipc6.tclass, fl6.flowlabel);
1521
1522 dst = ip6_sk_dst_lookup_flow(sk, &fl6, final_p, connected);
1523 if (IS_ERR(dst)) {
1524 err = PTR_ERR(dst);
1525 dst = NULL;
1526 goto out;
1527 }
1528
1529 if (ipc6.hlimit < 0)
1530 ipc6.hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
1531
1532 if (msg->msg_flags&MSG_CONFIRM)
1533 goto do_confirm;
1534back_from_confirm:
1535
1536 /* Lockless fast path for the non-corking case */
1537 if (!corkreq) {
1538 struct inet_cork_full cork;
1539 struct sk_buff *skb;
1540
1541 skb = ip6_make_skb(sk, getfrag, msg, ulen,
1542 sizeof(struct udphdr), &ipc6,
1543 &fl6, (struct rt6_info *)dst,
1544 msg->msg_flags, &cork);
1545 err = PTR_ERR(skb);
1546 if (!IS_ERR_OR_NULL(skb))
1547 err = udp_v6_send_skb(skb, &fl6, &cork.base);
1548 goto out;
1549 }
1550
1551 lock_sock(sk);
1552 if (unlikely(up->pending)) {
1553 /* The socket is already corked while preparing it. */
1554 /* ... which is an evident application bug. --ANK */
1555 release_sock(sk);
1556
1557 net_dbg_ratelimited("udp cork app bug 2\n");
1558 err = -EINVAL;
1559 goto out;
1560 }
1561
1562 up->pending = AF_INET6;
1563
1564do_append_data:
1565 if (ipc6.dontfrag < 0)
1566 ipc6.dontfrag = np->dontfrag;
1567 up->len += ulen;
1568 err = ip6_append_data(sk, getfrag, msg, ulen, sizeof(struct udphdr),
1569 &ipc6, &fl6, (struct rt6_info *)dst,
1570 corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags);
1571 if (err)
1572 udp_v6_flush_pending_frames(sk);
1573 else if (!corkreq)
1574 err = udp_v6_push_pending_frames(sk);
1575 else if (unlikely(skb_queue_empty(&sk->sk_write_queue)))
1576 up->pending = 0;
1577
1578 if (err > 0)
1579 err = np->recverr ? net_xmit_errno(err) : 0;
1580 release_sock(sk);
1581
1582out:
1583 dst_release(dst);
1584out_no_dst:
1585 fl6_sock_release(flowlabel);
1586 txopt_put(opt_to_free);
1587 if (!err)
1588 return len;
1589 /*
1590 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space. Reporting
1591 * ENOBUFS might not be good (it's not tunable per se), but otherwise
1592 * we don't have a good statistic (IpOutDiscards but it can be too many
1593 * things). We could add another new stat but at least for now that
1594 * seems like overkill.
1595 */
1596 if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) {
1597 UDP6_INC_STATS(sock_net(sk),
1598 UDP_MIB_SNDBUFERRORS, is_udplite);
1599 }
1600 return err;
1601
1602do_confirm:
1603 if (msg->msg_flags & MSG_PROBE)
1604 dst_confirm_neigh(dst, &fl6.daddr);
1605 if (!(msg->msg_flags&MSG_PROBE) || len)
1606 goto back_from_confirm;
1607 err = 0;
1608 goto out;
1609}
1610
1611void udpv6_destroy_sock(struct sock *sk)
1612{
1613 struct udp_sock *up = udp_sk(sk);
1614 lock_sock(sk);
1615
1616 /* protects from races with udp_abort() */
1617 sock_set_flag(sk, SOCK_DEAD);
1618 udp_v6_flush_pending_frames(sk);
1619 release_sock(sk);
1620
1621 if (static_branch_unlikely(&udpv6_encap_needed_key)) {
1622 if (up->encap_type) {
1623 void (*encap_destroy)(struct sock *sk);
1624 encap_destroy = READ_ONCE(up->encap_destroy);
1625 if (encap_destroy)
1626 encap_destroy(sk);
1627 }
1628 if (up->encap_enabled) {
1629 static_branch_dec(&udpv6_encap_needed_key);
1630 udp_encap_disable();
1631 }
1632 }
1633
1634 inet6_destroy_sock(sk);
1635}
1636
1637/*
1638 * Socket option code for UDP
1639 */
1640int udpv6_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
1641 unsigned int optlen)
1642{
1643 if (level == SOL_UDP || level == SOL_UDPLITE)
1644 return udp_lib_setsockopt(sk, level, optname,
1645 optval, optlen,
1646 udp_v6_push_pending_frames);
1647 return ipv6_setsockopt(sk, level, optname, optval, optlen);
1648}
1649
1650int udpv6_getsockopt(struct sock *sk, int level, int optname,
1651 char __user *optval, int __user *optlen)
1652{
1653 if (level == SOL_UDP || level == SOL_UDPLITE)
1654 return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1655 return ipv6_getsockopt(sk, level, optname, optval, optlen);
1656}
1657
1658/* thinking of making this const? Don't.
1659 * early_demux can change based on sysctl.
1660 */
1661static struct inet6_protocol udpv6_protocol = {
1662 .early_demux = udp_v6_early_demux,
1663 .early_demux_handler = udp_v6_early_demux,
1664 .handler = udpv6_rcv,
1665 .err_handler = udpv6_err,
1666 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1667};
1668
1669/* ------------------------------------------------------------------------ */
1670#ifdef CONFIG_PROC_FS
1671int udp6_seq_show(struct seq_file *seq, void *v)
1672{
1673 if (v == SEQ_START_TOKEN) {
1674 seq_puts(seq, IPV6_SEQ_DGRAM_HEADER);
1675 } else {
1676 int bucket = ((struct udp_iter_state *)seq->private)->bucket;
1677 struct inet_sock *inet = inet_sk(v);
1678 __u16 srcp = ntohs(inet->inet_sport);
1679 __u16 destp = ntohs(inet->inet_dport);
1680 __ip6_dgram_sock_seq_show(seq, v, srcp, destp,
1681 udp_rqueue_get(v), bucket);
1682 }
1683 return 0;
1684}
1685
1686const struct seq_operations udp6_seq_ops = {
1687 .start = udp_seq_start,
1688 .next = udp_seq_next,
1689 .stop = udp_seq_stop,
1690 .show = udp6_seq_show,
1691};
1692EXPORT_SYMBOL(udp6_seq_ops);
1693
1694static struct udp_seq_afinfo udp6_seq_afinfo = {
1695 .family = AF_INET6,
1696 .udp_table = &udp_table,
1697};
1698
1699int __net_init udp6_proc_init(struct net *net)
1700{
1701 if (!proc_create_net_data("udp6", 0444, net->proc_net, &udp6_seq_ops,
1702 sizeof(struct udp_iter_state), &udp6_seq_afinfo))
1703 return -ENOMEM;
1704 return 0;
1705}
1706
1707void udp6_proc_exit(struct net *net)
1708{
1709 remove_proc_entry("udp6", net->proc_net);
1710}
1711#endif /* CONFIG_PROC_FS */
1712
1713/* ------------------------------------------------------------------------ */
1714
1715struct proto udpv6_prot = {
1716 .name = "UDPv6",
1717 .owner = THIS_MODULE,
1718 .close = udp_lib_close,
1719 .pre_connect = udpv6_pre_connect,
1720 .connect = ip6_datagram_connect,
1721 .disconnect = udp_disconnect,
1722 .ioctl = udp_ioctl,
1723 .init = udp_init_sock,
1724 .destroy = udpv6_destroy_sock,
1725 .setsockopt = udpv6_setsockopt,
1726 .getsockopt = udpv6_getsockopt,
1727 .sendmsg = udpv6_sendmsg,
1728 .recvmsg = udpv6_recvmsg,
1729 .release_cb = ip6_datagram_release_cb,
1730 .hash = udp_lib_hash,
1731 .unhash = udp_lib_unhash,
1732 .rehash = udp_v6_rehash,
1733 .get_port = udp_v6_get_port,
1734#ifdef CONFIG_BPF_SYSCALL
1735 .psock_update_sk_prot = udp_bpf_update_proto,
1736#endif
1737 .memory_allocated = &udp_memory_allocated,
1738 .sysctl_mem = sysctl_udp_mem,
1739 .sysctl_wmem_offset = offsetof(struct net, ipv4.sysctl_udp_wmem_min),
1740 .sysctl_rmem_offset = offsetof(struct net, ipv4.sysctl_udp_rmem_min),
1741 .obj_size = sizeof(struct udp6_sock),
1742 .h.udp_table = &udp_table,
1743 .diag_destroy = udp_abort,
1744};
1745
1746static struct inet_protosw udpv6_protosw = {
1747 .type = SOCK_DGRAM,
1748 .protocol = IPPROTO_UDP,
1749 .prot = &udpv6_prot,
1750 .ops = &inet6_dgram_ops,
1751 .flags = INET_PROTOSW_PERMANENT,
1752};
1753
1754int __init udpv6_init(void)
1755{
1756 int ret;
1757
1758 ret = inet6_add_protocol(&udpv6_protocol, IPPROTO_UDP);
1759 if (ret)
1760 goto out;
1761
1762 ret = inet6_register_protosw(&udpv6_protosw);
1763 if (ret)
1764 goto out_udpv6_protocol;
1765out:
1766 return ret;
1767
1768out_udpv6_protocol:
1769 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1770 goto out;
1771}
1772
1773void udpv6_exit(void)
1774{
1775 inet6_unregister_protosw(&udpv6_protosw);
1776 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1777}
1/*
2 * UDP over IPv6
3 * Linux INET6 implementation
4 *
5 * Authors:
6 * Pedro Roque <roque@di.fc.ul.pt>
7 *
8 * Based on linux/ipv4/udp.c
9 *
10 * Fixes:
11 * Hideaki YOSHIFUJI : sin6_scope_id support
12 * YOSHIFUJI Hideaki @USAGI and: Support IPV6_V6ONLY socket option, which
13 * Alexey Kuznetsov allow both IPv4 and IPv6 sockets to bind
14 * a single port at the same time.
15 * Kazunori MIYAZAWA @USAGI: change process style to use ip6_append_data
16 * YOSHIFUJI Hideaki @USAGI: convert /proc/net/udp6 to seq_file.
17 *
18 * This program is free software; you can redistribute it and/or
19 * modify it under the terms of the GNU General Public License
20 * as published by the Free Software Foundation; either version
21 * 2 of the License, or (at your option) any later version.
22 */
23
24#include <linux/errno.h>
25#include <linux/types.h>
26#include <linux/socket.h>
27#include <linux/sockios.h>
28#include <linux/net.h>
29#include <linux/in6.h>
30#include <linux/netdevice.h>
31#include <linux/if_arp.h>
32#include <linux/ipv6.h>
33#include <linux/icmpv6.h>
34#include <linux/init.h>
35#include <linux/module.h>
36#include <linux/skbuff.h>
37#include <linux/slab.h>
38#include <asm/uaccess.h>
39
40#include <net/ndisc.h>
41#include <net/protocol.h>
42#include <net/transp_v6.h>
43#include <net/ip6_route.h>
44#include <net/raw.h>
45#include <net/tcp_states.h>
46#include <net/ip6_checksum.h>
47#include <net/xfrm.h>
48#include <net/inet6_hashtables.h>
49#include <net/busy_poll.h>
50
51#include <linux/proc_fs.h>
52#include <linux/seq_file.h>
53#include <trace/events/skb.h>
54#include "udp_impl.h"
55
56static unsigned int udp6_ehashfn(struct net *net,
57 const struct in6_addr *laddr,
58 const u16 lport,
59 const struct in6_addr *faddr,
60 const __be16 fport)
61{
62 static u32 udp6_ehash_secret __read_mostly;
63 static u32 udp_ipv6_hash_secret __read_mostly;
64
65 u32 lhash, fhash;
66
67 net_get_random_once(&udp6_ehash_secret,
68 sizeof(udp6_ehash_secret));
69 net_get_random_once(&udp_ipv6_hash_secret,
70 sizeof(udp_ipv6_hash_secret));
71
72 lhash = (__force u32)laddr->s6_addr32[3];
73 fhash = __ipv6_addr_jhash(faddr, udp_ipv6_hash_secret);
74
75 return __inet6_ehashfn(lhash, lport, fhash, fport,
76 udp_ipv6_hash_secret + net_hash_mix(net));
77}
78
79int ipv6_rcv_saddr_equal(const struct sock *sk, const struct sock *sk2)
80{
81 const struct in6_addr *sk2_rcv_saddr6 = inet6_rcv_saddr(sk2);
82 int sk_ipv6only = ipv6_only_sock(sk);
83 int sk2_ipv6only = inet_v6_ipv6only(sk2);
84 int addr_type = ipv6_addr_type(&sk->sk_v6_rcv_saddr);
85 int addr_type2 = sk2_rcv_saddr6 ? ipv6_addr_type(sk2_rcv_saddr6) : IPV6_ADDR_MAPPED;
86
87 /* if both are mapped, treat as IPv4 */
88 if (addr_type == IPV6_ADDR_MAPPED && addr_type2 == IPV6_ADDR_MAPPED)
89 return (!sk2_ipv6only &&
90 (!sk->sk_rcv_saddr || !sk2->sk_rcv_saddr ||
91 sk->sk_rcv_saddr == sk2->sk_rcv_saddr));
92
93 if (addr_type2 == IPV6_ADDR_ANY &&
94 !(sk2_ipv6only && addr_type == IPV6_ADDR_MAPPED))
95 return 1;
96
97 if (addr_type == IPV6_ADDR_ANY &&
98 !(sk_ipv6only && addr_type2 == IPV6_ADDR_MAPPED))
99 return 1;
100
101 if (sk2_rcv_saddr6 &&
102 ipv6_addr_equal(&sk->sk_v6_rcv_saddr, sk2_rcv_saddr6))
103 return 1;
104
105 return 0;
106}
107
108static unsigned int udp6_portaddr_hash(struct net *net,
109 const struct in6_addr *addr6,
110 unsigned int port)
111{
112 unsigned int hash, mix = net_hash_mix(net);
113
114 if (ipv6_addr_any(addr6))
115 hash = jhash_1word(0, mix);
116 else if (ipv6_addr_v4mapped(addr6))
117 hash = jhash_1word((__force u32)addr6->s6_addr32[3], mix);
118 else
119 hash = jhash2((__force u32 *)addr6->s6_addr32, 4, mix);
120
121 return hash ^ port;
122}
123
124
125int udp_v6_get_port(struct sock *sk, unsigned short snum)
126{
127 unsigned int hash2_nulladdr =
128 udp6_portaddr_hash(sock_net(sk), &in6addr_any, snum);
129 unsigned int hash2_partial =
130 udp6_portaddr_hash(sock_net(sk), &sk->sk_v6_rcv_saddr, 0);
131
132 /* precompute partial secondary hash */
133 udp_sk(sk)->udp_portaddr_hash = hash2_partial;
134 return udp_lib_get_port(sk, snum, ipv6_rcv_saddr_equal, hash2_nulladdr);
135}
136
137static void udp_v6_rehash(struct sock *sk)
138{
139 u16 new_hash = udp6_portaddr_hash(sock_net(sk),
140 &sk->sk_v6_rcv_saddr,
141 inet_sk(sk)->inet_num);
142
143 udp_lib_rehash(sk, new_hash);
144}
145
146static inline int compute_score(struct sock *sk, struct net *net,
147 unsigned short hnum,
148 const struct in6_addr *saddr, __be16 sport,
149 const struct in6_addr *daddr, __be16 dport,
150 int dif)
151{
152 int score = -1;
153
154 if (net_eq(sock_net(sk), net) && udp_sk(sk)->udp_port_hash == hnum &&
155 sk->sk_family == PF_INET6) {
156 struct inet_sock *inet = inet_sk(sk);
157
158 score = 0;
159 if (inet->inet_dport) {
160 if (inet->inet_dport != sport)
161 return -1;
162 score++;
163 }
164 if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr)) {
165 if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
166 return -1;
167 score++;
168 }
169 if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
170 if (!ipv6_addr_equal(&sk->sk_v6_daddr, saddr))
171 return -1;
172 score++;
173 }
174 if (sk->sk_bound_dev_if) {
175 if (sk->sk_bound_dev_if != dif)
176 return -1;
177 score++;
178 }
179 }
180 return score;
181}
182
183#define SCORE2_MAX (1 + 1 + 1)
184static inline int compute_score2(struct sock *sk, struct net *net,
185 const struct in6_addr *saddr, __be16 sport,
186 const struct in6_addr *daddr, unsigned short hnum,
187 int dif)
188{
189 int score = -1;
190
191 if (net_eq(sock_net(sk), net) && udp_sk(sk)->udp_port_hash == hnum &&
192 sk->sk_family == PF_INET6) {
193 struct inet_sock *inet = inet_sk(sk);
194
195 if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
196 return -1;
197 score = 0;
198 if (inet->inet_dport) {
199 if (inet->inet_dport != sport)
200 return -1;
201 score++;
202 }
203 if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
204 if (!ipv6_addr_equal(&sk->sk_v6_daddr, saddr))
205 return -1;
206 score++;
207 }
208 if (sk->sk_bound_dev_if) {
209 if (sk->sk_bound_dev_if != dif)
210 return -1;
211 score++;
212 }
213 }
214 return score;
215}
216
217
218/* called with read_rcu_lock() */
219static struct sock *udp6_lib_lookup2(struct net *net,
220 const struct in6_addr *saddr, __be16 sport,
221 const struct in6_addr *daddr, unsigned int hnum, int dif,
222 struct udp_hslot *hslot2, unsigned int slot2)
223{
224 struct sock *sk, *result;
225 struct hlist_nulls_node *node;
226 int score, badness, matches = 0, reuseport = 0;
227 u32 hash = 0;
228
229begin:
230 result = NULL;
231 badness = -1;
232 udp_portaddr_for_each_entry_rcu(sk, node, &hslot2->head) {
233 score = compute_score2(sk, net, saddr, sport,
234 daddr, hnum, dif);
235 if (score > badness) {
236 result = sk;
237 badness = score;
238 reuseport = sk->sk_reuseport;
239 if (reuseport) {
240 hash = udp6_ehashfn(net, daddr, hnum,
241 saddr, sport);
242 matches = 1;
243 } else if (score == SCORE2_MAX)
244 goto exact_match;
245 } else if (score == badness && reuseport) {
246 matches++;
247 if (((u64)hash * matches) >> 32 == 0)
248 result = sk;
249 hash = next_pseudo_random32(hash);
250 }
251 }
252 /*
253 * if the nulls value we got at the end of this lookup is
254 * not the expected one, we must restart lookup.
255 * We probably met an item that was moved to another chain.
256 */
257 if (get_nulls_value(node) != slot2)
258 goto begin;
259
260 if (result) {
261exact_match:
262 if (unlikely(!atomic_inc_not_zero_hint(&result->sk_refcnt, 2)))
263 result = NULL;
264 else if (unlikely(compute_score2(result, net, saddr, sport,
265 daddr, hnum, dif) < badness)) {
266 sock_put(result);
267 goto begin;
268 }
269 }
270 return result;
271}
272
273struct sock *__udp6_lib_lookup(struct net *net,
274 const struct in6_addr *saddr, __be16 sport,
275 const struct in6_addr *daddr, __be16 dport,
276 int dif, struct udp_table *udptable)
277{
278 struct sock *sk, *result;
279 struct hlist_nulls_node *node;
280 unsigned short hnum = ntohs(dport);
281 unsigned int hash2, slot2, slot = udp_hashfn(net, hnum, udptable->mask);
282 struct udp_hslot *hslot2, *hslot = &udptable->hash[slot];
283 int score, badness, matches = 0, reuseport = 0;
284 u32 hash = 0;
285
286 rcu_read_lock();
287 if (hslot->count > 10) {
288 hash2 = udp6_portaddr_hash(net, daddr, hnum);
289 slot2 = hash2 & udptable->mask;
290 hslot2 = &udptable->hash2[slot2];
291 if (hslot->count < hslot2->count)
292 goto begin;
293
294 result = udp6_lib_lookup2(net, saddr, sport,
295 daddr, hnum, dif,
296 hslot2, slot2);
297 if (!result) {
298 hash2 = udp6_portaddr_hash(net, &in6addr_any, hnum);
299 slot2 = hash2 & udptable->mask;
300 hslot2 = &udptable->hash2[slot2];
301 if (hslot->count < hslot2->count)
302 goto begin;
303
304 result = udp6_lib_lookup2(net, saddr, sport,
305 &in6addr_any, hnum, dif,
306 hslot2, slot2);
307 }
308 rcu_read_unlock();
309 return result;
310 }
311begin:
312 result = NULL;
313 badness = -1;
314 sk_nulls_for_each_rcu(sk, node, &hslot->head) {
315 score = compute_score(sk, net, hnum, saddr, sport, daddr, dport, dif);
316 if (score > badness) {
317 result = sk;
318 badness = score;
319 reuseport = sk->sk_reuseport;
320 if (reuseport) {
321 hash = udp6_ehashfn(net, daddr, hnum,
322 saddr, sport);
323 matches = 1;
324 }
325 } else if (score == badness && reuseport) {
326 matches++;
327 if (((u64)hash * matches) >> 32 == 0)
328 result = sk;
329 hash = next_pseudo_random32(hash);
330 }
331 }
332 /*
333 * if the nulls value we got at the end of this lookup is
334 * not the expected one, we must restart lookup.
335 * We probably met an item that was moved to another chain.
336 */
337 if (get_nulls_value(node) != slot)
338 goto begin;
339
340 if (result) {
341 if (unlikely(!atomic_inc_not_zero_hint(&result->sk_refcnt, 2)))
342 result = NULL;
343 else if (unlikely(compute_score(result, net, hnum, saddr, sport,
344 daddr, dport, dif) < badness)) {
345 sock_put(result);
346 goto begin;
347 }
348 }
349 rcu_read_unlock();
350 return result;
351}
352EXPORT_SYMBOL_GPL(__udp6_lib_lookup);
353
354static struct sock *__udp6_lib_lookup_skb(struct sk_buff *skb,
355 __be16 sport, __be16 dport,
356 struct udp_table *udptable)
357{
358 struct sock *sk;
359 const struct ipv6hdr *iph = ipv6_hdr(skb);
360
361 if (unlikely(sk = skb_steal_sock(skb)))
362 return sk;
363 return __udp6_lib_lookup(dev_net(skb_dst(skb)->dev), &iph->saddr, sport,
364 &iph->daddr, dport, inet6_iif(skb),
365 udptable);
366}
367
368struct sock *udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport,
369 const struct in6_addr *daddr, __be16 dport, int dif)
370{
371 return __udp6_lib_lookup(net, saddr, sport, daddr, dport, dif, &udp_table);
372}
373EXPORT_SYMBOL_GPL(udp6_lib_lookup);
374
375
376/*
377 * This should be easy, if there is something there we
378 * return it, otherwise we block.
379 */
380
381int udpv6_recvmsg(struct kiocb *iocb, struct sock *sk,
382 struct msghdr *msg, size_t len,
383 int noblock, int flags, int *addr_len)
384{
385 struct ipv6_pinfo *np = inet6_sk(sk);
386 struct inet_sock *inet = inet_sk(sk);
387 struct sk_buff *skb;
388 unsigned int ulen, copied;
389 int peeked, off = 0;
390 int err;
391 int is_udplite = IS_UDPLITE(sk);
392 int is_udp4;
393 bool slow;
394
395 if (flags & MSG_ERRQUEUE)
396 return ipv6_recv_error(sk, msg, len, addr_len);
397
398 if (np->rxpmtu && np->rxopt.bits.rxpmtu)
399 return ipv6_recv_rxpmtu(sk, msg, len, addr_len);
400
401try_again:
402 skb = __skb_recv_datagram(sk, flags | (noblock ? MSG_DONTWAIT : 0),
403 &peeked, &off, &err);
404 if (!skb)
405 goto out;
406
407 ulen = skb->len - sizeof(struct udphdr);
408 copied = len;
409 if (copied > ulen)
410 copied = ulen;
411 else if (copied < ulen)
412 msg->msg_flags |= MSG_TRUNC;
413
414 is_udp4 = (skb->protocol == htons(ETH_P_IP));
415
416 /*
417 * If checksum is needed at all, try to do it while copying the
418 * data. If the data is truncated, or if we only want a partial
419 * coverage checksum (UDP-Lite), do it before the copy.
420 */
421
422 if (copied < ulen || UDP_SKB_CB(skb)->partial_cov) {
423 if (udp_lib_checksum_complete(skb))
424 goto csum_copy_err;
425 }
426
427 if (skb_csum_unnecessary(skb))
428 err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr),
429 msg->msg_iov, copied);
430 else {
431 err = skb_copy_and_csum_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov);
432 if (err == -EINVAL)
433 goto csum_copy_err;
434 }
435 if (unlikely(err)) {
436 trace_kfree_skb(skb, udpv6_recvmsg);
437 if (!peeked) {
438 atomic_inc(&sk->sk_drops);
439 if (is_udp4)
440 UDP_INC_STATS_USER(sock_net(sk),
441 UDP_MIB_INERRORS,
442 is_udplite);
443 else
444 UDP6_INC_STATS_USER(sock_net(sk),
445 UDP_MIB_INERRORS,
446 is_udplite);
447 }
448 goto out_free;
449 }
450 if (!peeked) {
451 if (is_udp4)
452 UDP_INC_STATS_USER(sock_net(sk),
453 UDP_MIB_INDATAGRAMS, is_udplite);
454 else
455 UDP6_INC_STATS_USER(sock_net(sk),
456 UDP_MIB_INDATAGRAMS, is_udplite);
457 }
458
459 sock_recv_ts_and_drops(msg, sk, skb);
460
461 /* Copy the address. */
462 if (msg->msg_name) {
463 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
464 sin6->sin6_family = AF_INET6;
465 sin6->sin6_port = udp_hdr(skb)->source;
466 sin6->sin6_flowinfo = 0;
467
468 if (is_udp4) {
469 ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
470 &sin6->sin6_addr);
471 sin6->sin6_scope_id = 0;
472 } else {
473 sin6->sin6_addr = ipv6_hdr(skb)->saddr;
474 sin6->sin6_scope_id =
475 ipv6_iface_scope_id(&sin6->sin6_addr,
476 IP6CB(skb)->iif);
477 }
478 *addr_len = sizeof(*sin6);
479 }
480
481 if (np->rxopt.all)
482 ip6_datagram_recv_common_ctl(sk, msg, skb);
483
484 if (is_udp4) {
485 if (inet->cmsg_flags)
486 ip_cmsg_recv(msg, skb);
487 } else {
488 if (np->rxopt.all)
489 ip6_datagram_recv_specific_ctl(sk, msg, skb);
490 }
491
492 err = copied;
493 if (flags & MSG_TRUNC)
494 err = ulen;
495
496out_free:
497 skb_free_datagram_locked(sk, skb);
498out:
499 return err;
500
501csum_copy_err:
502 slow = lock_sock_fast(sk);
503 if (!skb_kill_datagram(sk, skb, flags)) {
504 if (is_udp4) {
505 UDP_INC_STATS_USER(sock_net(sk),
506 UDP_MIB_CSUMERRORS, is_udplite);
507 UDP_INC_STATS_USER(sock_net(sk),
508 UDP_MIB_INERRORS, is_udplite);
509 } else {
510 UDP6_INC_STATS_USER(sock_net(sk),
511 UDP_MIB_CSUMERRORS, is_udplite);
512 UDP6_INC_STATS_USER(sock_net(sk),
513 UDP_MIB_INERRORS, is_udplite);
514 }
515 }
516 unlock_sock_fast(sk, slow);
517
518 if (noblock)
519 return -EAGAIN;
520
521 /* starting over for a new packet */
522 msg->msg_flags &= ~MSG_TRUNC;
523 goto try_again;
524}
525
526void __udp6_lib_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
527 u8 type, u8 code, int offset, __be32 info,
528 struct udp_table *udptable)
529{
530 struct ipv6_pinfo *np;
531 const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data;
532 const struct in6_addr *saddr = &hdr->saddr;
533 const struct in6_addr *daddr = &hdr->daddr;
534 struct udphdr *uh = (struct udphdr*)(skb->data+offset);
535 struct sock *sk;
536 int err;
537
538 sk = __udp6_lib_lookup(dev_net(skb->dev), daddr, uh->dest,
539 saddr, uh->source, inet6_iif(skb), udptable);
540 if (sk == NULL)
541 return;
542
543 if (type == ICMPV6_PKT_TOOBIG) {
544 if (!ip6_sk_accept_pmtu(sk))
545 goto out;
546 ip6_sk_update_pmtu(skb, sk, info);
547 }
548 if (type == NDISC_REDIRECT) {
549 ip6_sk_redirect(skb, sk);
550 goto out;
551 }
552
553 np = inet6_sk(sk);
554
555 if (!icmpv6_err_convert(type, code, &err) && !np->recverr)
556 goto out;
557
558 if (sk->sk_state != TCP_ESTABLISHED && !np->recverr)
559 goto out;
560
561 if (np->recverr)
562 ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1));
563
564 sk->sk_err = err;
565 sk->sk_error_report(sk);
566out:
567 sock_put(sk);
568}
569
570static int __udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
571{
572 int rc;
573
574 if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
575 sock_rps_save_rxhash(sk, skb);
576 sk_mark_napi_id(sk, skb);
577 }
578
579 rc = sock_queue_rcv_skb(sk, skb);
580 if (rc < 0) {
581 int is_udplite = IS_UDPLITE(sk);
582
583 /* Note that an ENOMEM error is charged twice */
584 if (rc == -ENOMEM)
585 UDP6_INC_STATS_BH(sock_net(sk),
586 UDP_MIB_RCVBUFERRORS, is_udplite);
587 UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
588 kfree_skb(skb);
589 return -1;
590 }
591 return 0;
592}
593
594static __inline__ void udpv6_err(struct sk_buff *skb,
595 struct inet6_skb_parm *opt, u8 type,
596 u8 code, int offset, __be32 info )
597{
598 __udp6_lib_err(skb, opt, type, code, offset, info, &udp_table);
599}
600
601static struct static_key udpv6_encap_needed __read_mostly;
602void udpv6_encap_enable(void)
603{
604 if (!static_key_enabled(&udpv6_encap_needed))
605 static_key_slow_inc(&udpv6_encap_needed);
606}
607EXPORT_SYMBOL(udpv6_encap_enable);
608
609int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
610{
611 struct udp_sock *up = udp_sk(sk);
612 int rc;
613 int is_udplite = IS_UDPLITE(sk);
614
615 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
616 goto drop;
617
618 if (static_key_false(&udpv6_encap_needed) && up->encap_type) {
619 int (*encap_rcv)(struct sock *sk, struct sk_buff *skb);
620
621 /*
622 * This is an encapsulation socket so pass the skb to
623 * the socket's udp_encap_rcv() hook. Otherwise, just
624 * fall through and pass this up the UDP socket.
625 * up->encap_rcv() returns the following value:
626 * =0 if skb was successfully passed to the encap
627 * handler or was discarded by it.
628 * >0 if skb should be passed on to UDP.
629 * <0 if skb should be resubmitted as proto -N
630 */
631
632 /* if we're overly short, let UDP handle it */
633 encap_rcv = ACCESS_ONCE(up->encap_rcv);
634 if (skb->len > sizeof(struct udphdr) && encap_rcv != NULL) {
635 int ret;
636
637 ret = encap_rcv(sk, skb);
638 if (ret <= 0) {
639 UDP_INC_STATS_BH(sock_net(sk),
640 UDP_MIB_INDATAGRAMS,
641 is_udplite);
642 return -ret;
643 }
644 }
645
646 /* FALLTHROUGH -- it's a UDP Packet */
647 }
648
649 /*
650 * UDP-Lite specific tests, ignored on UDP sockets (see net/ipv4/udp.c).
651 */
652 if ((is_udplite & UDPLITE_RECV_CC) && UDP_SKB_CB(skb)->partial_cov) {
653
654 if (up->pcrlen == 0) { /* full coverage was set */
655 LIMIT_NETDEBUG(KERN_WARNING "UDPLITE6: partial coverage"
656 " %d while full coverage %d requested\n",
657 UDP_SKB_CB(skb)->cscov, skb->len);
658 goto drop;
659 }
660 if (UDP_SKB_CB(skb)->cscov < up->pcrlen) {
661 LIMIT_NETDEBUG(KERN_WARNING "UDPLITE6: coverage %d "
662 "too small, need min %d\n",
663 UDP_SKB_CB(skb)->cscov, up->pcrlen);
664 goto drop;
665 }
666 }
667
668 if (rcu_access_pointer(sk->sk_filter)) {
669 if (udp_lib_checksum_complete(skb))
670 goto csum_error;
671 }
672
673 if (sk_rcvqueues_full(sk, skb, sk->sk_rcvbuf))
674 goto drop;
675
676 skb_dst_drop(skb);
677
678 bh_lock_sock(sk);
679 rc = 0;
680 if (!sock_owned_by_user(sk))
681 rc = __udpv6_queue_rcv_skb(sk, skb);
682 else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) {
683 bh_unlock_sock(sk);
684 goto drop;
685 }
686 bh_unlock_sock(sk);
687
688 return rc;
689csum_error:
690 UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite);
691drop:
692 UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
693 atomic_inc(&sk->sk_drops);
694 kfree_skb(skb);
695 return -1;
696}
697
698static struct sock *udp_v6_mcast_next(struct net *net, struct sock *sk,
699 __be16 loc_port, const struct in6_addr *loc_addr,
700 __be16 rmt_port, const struct in6_addr *rmt_addr,
701 int dif)
702{
703 struct hlist_nulls_node *node;
704 struct sock *s = sk;
705 unsigned short num = ntohs(loc_port);
706
707 sk_nulls_for_each_from(s, node) {
708 struct inet_sock *inet = inet_sk(s);
709
710 if (!net_eq(sock_net(s), net))
711 continue;
712
713 if (udp_sk(s)->udp_port_hash == num &&
714 s->sk_family == PF_INET6) {
715 if (inet->inet_dport) {
716 if (inet->inet_dport != rmt_port)
717 continue;
718 }
719 if (!ipv6_addr_any(&sk->sk_v6_daddr) &&
720 !ipv6_addr_equal(&sk->sk_v6_daddr, rmt_addr))
721 continue;
722
723 if (s->sk_bound_dev_if && s->sk_bound_dev_if != dif)
724 continue;
725
726 if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr)) {
727 if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, loc_addr))
728 continue;
729 }
730 if (!inet6_mc_check(s, loc_addr, rmt_addr))
731 continue;
732 return s;
733 }
734 }
735 return NULL;
736}
737
738static void flush_stack(struct sock **stack, unsigned int count,
739 struct sk_buff *skb, unsigned int final)
740{
741 struct sk_buff *skb1 = NULL;
742 struct sock *sk;
743 unsigned int i;
744
745 for (i = 0; i < count; i++) {
746 sk = stack[i];
747 if (likely(skb1 == NULL))
748 skb1 = (i == final) ? skb : skb_clone(skb, GFP_ATOMIC);
749 if (!skb1) {
750 atomic_inc(&sk->sk_drops);
751 UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_RCVBUFERRORS,
752 IS_UDPLITE(sk));
753 UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS,
754 IS_UDPLITE(sk));
755 }
756
757 if (skb1 && udpv6_queue_rcv_skb(sk, skb1) <= 0)
758 skb1 = NULL;
759 }
760 if (unlikely(skb1))
761 kfree_skb(skb1);
762}
763/*
764 * Note: called only from the BH handler context,
765 * so we don't need to lock the hashes.
766 */
767static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
768 const struct in6_addr *saddr, const struct in6_addr *daddr,
769 struct udp_table *udptable)
770{
771 struct sock *sk, *stack[256 / sizeof(struct sock *)];
772 const struct udphdr *uh = udp_hdr(skb);
773 struct udp_hslot *hslot = udp_hashslot(udptable, net, ntohs(uh->dest));
774 int dif;
775 unsigned int i, count = 0;
776
777 spin_lock(&hslot->lock);
778 sk = sk_nulls_head(&hslot->head);
779 dif = inet6_iif(skb);
780 sk = udp_v6_mcast_next(net, sk, uh->dest, daddr, uh->source, saddr, dif);
781 while (sk) {
782 stack[count++] = sk;
783 sk = udp_v6_mcast_next(net, sk_nulls_next(sk), uh->dest, daddr,
784 uh->source, saddr, dif);
785 if (unlikely(count == ARRAY_SIZE(stack))) {
786 if (!sk)
787 break;
788 flush_stack(stack, count, skb, ~0);
789 count = 0;
790 }
791 }
792 /*
793 * before releasing the lock, we must take reference on sockets
794 */
795 for (i = 0; i < count; i++)
796 sock_hold(stack[i]);
797
798 spin_unlock(&hslot->lock);
799
800 if (count) {
801 flush_stack(stack, count, skb, count - 1);
802
803 for (i = 0; i < count; i++)
804 sock_put(stack[i]);
805 } else {
806 kfree_skb(skb);
807 }
808 return 0;
809}
810
811int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
812 int proto)
813{
814 struct net *net = dev_net(skb->dev);
815 struct sock *sk;
816 struct udphdr *uh;
817 const struct in6_addr *saddr, *daddr;
818 u32 ulen = 0;
819
820 if (!pskb_may_pull(skb, sizeof(struct udphdr)))
821 goto discard;
822
823 saddr = &ipv6_hdr(skb)->saddr;
824 daddr = &ipv6_hdr(skb)->daddr;
825 uh = udp_hdr(skb);
826
827 ulen = ntohs(uh->len);
828 if (ulen > skb->len)
829 goto short_packet;
830
831 if (proto == IPPROTO_UDP) {
832 /* UDP validates ulen. */
833
834 /* Check for jumbo payload */
835 if (ulen == 0)
836 ulen = skb->len;
837
838 if (ulen < sizeof(*uh))
839 goto short_packet;
840
841 if (ulen < skb->len) {
842 if (pskb_trim_rcsum(skb, ulen))
843 goto short_packet;
844 saddr = &ipv6_hdr(skb)->saddr;
845 daddr = &ipv6_hdr(skb)->daddr;
846 uh = udp_hdr(skb);
847 }
848 }
849
850 if (udp6_csum_init(skb, uh, proto))
851 goto csum_error;
852
853 /*
854 * Multicast receive code
855 */
856 if (ipv6_addr_is_multicast(daddr))
857 return __udp6_lib_mcast_deliver(net, skb,
858 saddr, daddr, udptable);
859
860 /* Unicast */
861
862 /*
863 * check socket cache ... must talk to Alan about his plans
864 * for sock caches... i'll skip this for now.
865 */
866 sk = __udp6_lib_lookup_skb(skb, uh->source, uh->dest, udptable);
867 if (sk != NULL) {
868 int ret;
869
870 ret = udpv6_queue_rcv_skb(sk, skb);
871 sock_put(sk);
872
873 /* a return value > 0 means to resubmit the input, but
874 * it wants the return to be -protocol, or 0
875 */
876 if (ret > 0)
877 return -ret;
878
879 return 0;
880 }
881
882 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
883 goto discard;
884
885 if (udp_lib_checksum_complete(skb))
886 goto csum_error;
887
888 UDP6_INC_STATS_BH(net, UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE);
889 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
890
891 kfree_skb(skb);
892 return 0;
893
894short_packet:
895 LIMIT_NETDEBUG(KERN_DEBUG "UDP%sv6: short packet: From [%pI6c]:%u %d/%d to [%pI6c]:%u\n",
896 proto == IPPROTO_UDPLITE ? "-Lite" : "",
897 saddr,
898 ntohs(uh->source),
899 ulen,
900 skb->len,
901 daddr,
902 ntohs(uh->dest));
903 goto discard;
904csum_error:
905 UDP6_INC_STATS_BH(net, UDP_MIB_CSUMERRORS, proto == IPPROTO_UDPLITE);
906discard:
907 UDP6_INC_STATS_BH(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE);
908 kfree_skb(skb);
909 return 0;
910}
911
912static __inline__ int udpv6_rcv(struct sk_buff *skb)
913{
914 return __udp6_lib_rcv(skb, &udp_table, IPPROTO_UDP);
915}
916
917/*
918 * Throw away all pending data and cancel the corking. Socket is locked.
919 */
920static void udp_v6_flush_pending_frames(struct sock *sk)
921{
922 struct udp_sock *up = udp_sk(sk);
923
924 if (up->pending == AF_INET)
925 udp_flush_pending_frames(sk);
926 else if (up->pending) {
927 up->len = 0;
928 up->pending = 0;
929 ip6_flush_pending_frames(sk);
930 }
931}
932
933/**
934 * udp6_hwcsum_outgoing - handle outgoing HW checksumming
935 * @sk: socket we are sending on
936 * @skb: sk_buff containing the filled-in UDP header
937 * (checksum field must be zeroed out)
938 */
939static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb,
940 const struct in6_addr *saddr,
941 const struct in6_addr *daddr, int len)
942{
943 unsigned int offset;
944 struct udphdr *uh = udp_hdr(skb);
945 __wsum csum = 0;
946
947 if (skb_queue_len(&sk->sk_write_queue) == 1) {
948 /* Only one fragment on the socket. */
949 skb->csum_start = skb_transport_header(skb) - skb->head;
950 skb->csum_offset = offsetof(struct udphdr, check);
951 uh->check = ~csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 0);
952 } else {
953 /*
954 * HW-checksum won't work as there are two or more
955 * fragments on the socket so that all csums of sk_buffs
956 * should be together
957 */
958 offset = skb_transport_offset(skb);
959 skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
960
961 skb->ip_summed = CHECKSUM_NONE;
962
963 skb_queue_walk(&sk->sk_write_queue, skb) {
964 csum = csum_add(csum, skb->csum);
965 }
966
967 uh->check = csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP,
968 csum);
969 if (uh->check == 0)
970 uh->check = CSUM_MANGLED_0;
971 }
972}
973
974/*
975 * Sending
976 */
977
978static int udp_v6_push_pending_frames(struct sock *sk)
979{
980 struct sk_buff *skb;
981 struct udphdr *uh;
982 struct udp_sock *up = udp_sk(sk);
983 struct inet_sock *inet = inet_sk(sk);
984 struct flowi6 *fl6;
985 int err = 0;
986 int is_udplite = IS_UDPLITE(sk);
987 __wsum csum = 0;
988
989 if (up->pending == AF_INET)
990 return udp_push_pending_frames(sk);
991
992 fl6 = &inet->cork.fl.u.ip6;
993
994 /* Grab the skbuff where UDP header space exists. */
995 if ((skb = skb_peek(&sk->sk_write_queue)) == NULL)
996 goto out;
997
998 /*
999 * Create a UDP header
1000 */
1001 uh = udp_hdr(skb);
1002 uh->source = fl6->fl6_sport;
1003 uh->dest = fl6->fl6_dport;
1004 uh->len = htons(up->len);
1005 uh->check = 0;
1006
1007 if (is_udplite)
1008 csum = udplite_csum_outgoing(sk, skb);
1009 else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */
1010 udp6_hwcsum_outgoing(sk, skb, &fl6->saddr, &fl6->daddr,
1011 up->len);
1012 goto send;
1013 } else
1014 csum = udp_csum_outgoing(sk, skb);
1015
1016 /* add protocol-dependent pseudo-header */
1017 uh->check = csum_ipv6_magic(&fl6->saddr, &fl6->daddr,
1018 up->len, fl6->flowi6_proto, csum);
1019 if (uh->check == 0)
1020 uh->check = CSUM_MANGLED_0;
1021
1022send:
1023 err = ip6_push_pending_frames(sk);
1024 if (err) {
1025 if (err == -ENOBUFS && !inet6_sk(sk)->recverr) {
1026 UDP6_INC_STATS_USER(sock_net(sk),
1027 UDP_MIB_SNDBUFERRORS, is_udplite);
1028 err = 0;
1029 }
1030 } else
1031 UDP6_INC_STATS_USER(sock_net(sk),
1032 UDP_MIB_OUTDATAGRAMS, is_udplite);
1033out:
1034 up->len = 0;
1035 up->pending = 0;
1036 return err;
1037}
1038
1039int udpv6_sendmsg(struct kiocb *iocb, struct sock *sk,
1040 struct msghdr *msg, size_t len)
1041{
1042 struct ipv6_txoptions opt_space;
1043 struct udp_sock *up = udp_sk(sk);
1044 struct inet_sock *inet = inet_sk(sk);
1045 struct ipv6_pinfo *np = inet6_sk(sk);
1046 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
1047 struct in6_addr *daddr, *final_p, final;
1048 struct ipv6_txoptions *opt = NULL;
1049 struct ip6_flowlabel *flowlabel = NULL;
1050 struct flowi6 fl6;
1051 struct dst_entry *dst;
1052 int addr_len = msg->msg_namelen;
1053 int ulen = len;
1054 int hlimit = -1;
1055 int tclass = -1;
1056 int dontfrag = -1;
1057 int corkreq = up->corkflag || msg->msg_flags&MSG_MORE;
1058 int err;
1059 int connected = 0;
1060 int is_udplite = IS_UDPLITE(sk);
1061 int (*getfrag)(void *, char *, int, int, int, struct sk_buff *);
1062
1063 /* destination address check */
1064 if (sin6) {
1065 if (addr_len < offsetof(struct sockaddr, sa_data))
1066 return -EINVAL;
1067
1068 switch (sin6->sin6_family) {
1069 case AF_INET6:
1070 if (addr_len < SIN6_LEN_RFC2133)
1071 return -EINVAL;
1072 daddr = &sin6->sin6_addr;
1073 break;
1074 case AF_INET:
1075 goto do_udp_sendmsg;
1076 case AF_UNSPEC:
1077 msg->msg_name = sin6 = NULL;
1078 msg->msg_namelen = addr_len = 0;
1079 daddr = NULL;
1080 break;
1081 default:
1082 return -EINVAL;
1083 }
1084 } else if (!up->pending) {
1085 if (sk->sk_state != TCP_ESTABLISHED)
1086 return -EDESTADDRREQ;
1087 daddr = &sk->sk_v6_daddr;
1088 } else
1089 daddr = NULL;
1090
1091 if (daddr) {
1092 if (ipv6_addr_v4mapped(daddr)) {
1093 struct sockaddr_in sin;
1094 sin.sin_family = AF_INET;
1095 sin.sin_port = sin6 ? sin6->sin6_port : inet->inet_dport;
1096 sin.sin_addr.s_addr = daddr->s6_addr32[3];
1097 msg->msg_name = &sin;
1098 msg->msg_namelen = sizeof(sin);
1099do_udp_sendmsg:
1100 if (__ipv6_only_sock(sk))
1101 return -ENETUNREACH;
1102 return udp_sendmsg(iocb, sk, msg, len);
1103 }
1104 }
1105
1106 if (up->pending == AF_INET)
1107 return udp_sendmsg(iocb, sk, msg, len);
1108
1109 /* Rough check on arithmetic overflow,
1110 better check is made in ip6_append_data().
1111 */
1112 if (len > INT_MAX - sizeof(struct udphdr))
1113 return -EMSGSIZE;
1114
1115 if (up->pending) {
1116 /*
1117 * There are pending frames.
1118 * The socket lock must be held while it's corked.
1119 */
1120 lock_sock(sk);
1121 if (likely(up->pending)) {
1122 if (unlikely(up->pending != AF_INET6)) {
1123 release_sock(sk);
1124 return -EAFNOSUPPORT;
1125 }
1126 dst = NULL;
1127 goto do_append_data;
1128 }
1129 release_sock(sk);
1130 }
1131 ulen += sizeof(struct udphdr);
1132
1133 memset(&fl6, 0, sizeof(fl6));
1134
1135 if (sin6) {
1136 if (sin6->sin6_port == 0)
1137 return -EINVAL;
1138
1139 fl6.fl6_dport = sin6->sin6_port;
1140 daddr = &sin6->sin6_addr;
1141
1142 if (np->sndflow) {
1143 fl6.flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK;
1144 if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) {
1145 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1146 if (flowlabel == NULL)
1147 return -EINVAL;
1148 }
1149 }
1150
1151 /*
1152 * Otherwise it will be difficult to maintain
1153 * sk->sk_dst_cache.
1154 */
1155 if (sk->sk_state == TCP_ESTABLISHED &&
1156 ipv6_addr_equal(daddr, &sk->sk_v6_daddr))
1157 daddr = &sk->sk_v6_daddr;
1158
1159 if (addr_len >= sizeof(struct sockaddr_in6) &&
1160 sin6->sin6_scope_id &&
1161 __ipv6_addr_needs_scope_id(__ipv6_addr_type(daddr)))
1162 fl6.flowi6_oif = sin6->sin6_scope_id;
1163 } else {
1164 if (sk->sk_state != TCP_ESTABLISHED)
1165 return -EDESTADDRREQ;
1166
1167 fl6.fl6_dport = inet->inet_dport;
1168 daddr = &sk->sk_v6_daddr;
1169 fl6.flowlabel = np->flow_label;
1170 connected = 1;
1171 }
1172
1173 if (!fl6.flowi6_oif)
1174 fl6.flowi6_oif = sk->sk_bound_dev_if;
1175
1176 if (!fl6.flowi6_oif)
1177 fl6.flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;
1178
1179 fl6.flowi6_mark = sk->sk_mark;
1180
1181 if (msg->msg_controllen) {
1182 opt = &opt_space;
1183 memset(opt, 0, sizeof(struct ipv6_txoptions));
1184 opt->tot_len = sizeof(*opt);
1185
1186 err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, &fl6, opt,
1187 &hlimit, &tclass, &dontfrag);
1188 if (err < 0) {
1189 fl6_sock_release(flowlabel);
1190 return err;
1191 }
1192 if ((fl6.flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) {
1193 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1194 if (flowlabel == NULL)
1195 return -EINVAL;
1196 }
1197 if (!(opt->opt_nflen|opt->opt_flen))
1198 opt = NULL;
1199 connected = 0;
1200 }
1201 if (opt == NULL)
1202 opt = np->opt;
1203 if (flowlabel)
1204 opt = fl6_merge_options(&opt_space, flowlabel, opt);
1205 opt = ipv6_fixup_options(&opt_space, opt);
1206
1207 fl6.flowi6_proto = sk->sk_protocol;
1208 if (!ipv6_addr_any(daddr))
1209 fl6.daddr = *daddr;
1210 else
1211 fl6.daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */
1212 if (ipv6_addr_any(&fl6.saddr) && !ipv6_addr_any(&np->saddr))
1213 fl6.saddr = np->saddr;
1214 fl6.fl6_sport = inet->inet_sport;
1215
1216 final_p = fl6_update_dst(&fl6, opt, &final);
1217 if (final_p)
1218 connected = 0;
1219
1220 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr)) {
1221 fl6.flowi6_oif = np->mcast_oif;
1222 connected = 0;
1223 } else if (!fl6.flowi6_oif)
1224 fl6.flowi6_oif = np->ucast_oif;
1225
1226 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
1227
1228 dst = ip6_sk_dst_lookup_flow(sk, &fl6, final_p);
1229 if (IS_ERR(dst)) {
1230 err = PTR_ERR(dst);
1231 dst = NULL;
1232 goto out;
1233 }
1234
1235 if (hlimit < 0) {
1236 if (ipv6_addr_is_multicast(&fl6.daddr))
1237 hlimit = np->mcast_hops;
1238 else
1239 hlimit = np->hop_limit;
1240 if (hlimit < 0)
1241 hlimit = ip6_dst_hoplimit(dst);
1242 }
1243
1244 if (tclass < 0)
1245 tclass = np->tclass;
1246
1247 if (msg->msg_flags&MSG_CONFIRM)
1248 goto do_confirm;
1249back_from_confirm:
1250
1251 lock_sock(sk);
1252 if (unlikely(up->pending)) {
1253 /* The socket is already corked while preparing it. */
1254 /* ... which is an evident application bug. --ANK */
1255 release_sock(sk);
1256
1257 LIMIT_NETDEBUG(KERN_DEBUG "udp cork app bug 2\n");
1258 err = -EINVAL;
1259 goto out;
1260 }
1261
1262 up->pending = AF_INET6;
1263
1264do_append_data:
1265 if (dontfrag < 0)
1266 dontfrag = np->dontfrag;
1267 up->len += ulen;
1268 getfrag = is_udplite ? udplite_getfrag : ip_generic_getfrag;
1269 err = ip6_append_data(sk, getfrag, msg->msg_iov, ulen,
1270 sizeof(struct udphdr), hlimit, tclass, opt, &fl6,
1271 (struct rt6_info*)dst,
1272 corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags, dontfrag);
1273 if (err)
1274 udp_v6_flush_pending_frames(sk);
1275 else if (!corkreq)
1276 err = udp_v6_push_pending_frames(sk);
1277 else if (unlikely(skb_queue_empty(&sk->sk_write_queue)))
1278 up->pending = 0;
1279
1280 if (dst) {
1281 if (connected) {
1282 ip6_dst_store(sk, dst,
1283 ipv6_addr_equal(&fl6.daddr, &sk->sk_v6_daddr) ?
1284 &sk->sk_v6_daddr : NULL,
1285#ifdef CONFIG_IPV6_SUBTREES
1286 ipv6_addr_equal(&fl6.saddr, &np->saddr) ?
1287 &np->saddr :
1288#endif
1289 NULL);
1290 } else {
1291 dst_release(dst);
1292 }
1293 dst = NULL;
1294 }
1295
1296 if (err > 0)
1297 err = np->recverr ? net_xmit_errno(err) : 0;
1298 release_sock(sk);
1299out:
1300 dst_release(dst);
1301 fl6_sock_release(flowlabel);
1302 if (!err)
1303 return len;
1304 /*
1305 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space. Reporting
1306 * ENOBUFS might not be good (it's not tunable per se), but otherwise
1307 * we don't have a good statistic (IpOutDiscards but it can be too many
1308 * things). We could add another new stat but at least for now that
1309 * seems like overkill.
1310 */
1311 if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) {
1312 UDP6_INC_STATS_USER(sock_net(sk),
1313 UDP_MIB_SNDBUFERRORS, is_udplite);
1314 }
1315 return err;
1316
1317do_confirm:
1318 dst_confirm(dst);
1319 if (!(msg->msg_flags&MSG_PROBE) || len)
1320 goto back_from_confirm;
1321 err = 0;
1322 goto out;
1323}
1324
1325void udpv6_destroy_sock(struct sock *sk)
1326{
1327 struct udp_sock *up = udp_sk(sk);
1328 lock_sock(sk);
1329 udp_v6_flush_pending_frames(sk);
1330 release_sock(sk);
1331
1332 if (static_key_false(&udpv6_encap_needed) && up->encap_type) {
1333 void (*encap_destroy)(struct sock *sk);
1334 encap_destroy = ACCESS_ONCE(up->encap_destroy);
1335 if (encap_destroy)
1336 encap_destroy(sk);
1337 }
1338
1339 inet6_destroy_sock(sk);
1340}
1341
1342/*
1343 * Socket option code for UDP
1344 */
1345int udpv6_setsockopt(struct sock *sk, int level, int optname,
1346 char __user *optval, unsigned int optlen)
1347{
1348 if (level == SOL_UDP || level == SOL_UDPLITE)
1349 return udp_lib_setsockopt(sk, level, optname, optval, optlen,
1350 udp_v6_push_pending_frames);
1351 return ipv6_setsockopt(sk, level, optname, optval, optlen);
1352}
1353
1354#ifdef CONFIG_COMPAT
1355int compat_udpv6_setsockopt(struct sock *sk, int level, int optname,
1356 char __user *optval, unsigned int optlen)
1357{
1358 if (level == SOL_UDP || level == SOL_UDPLITE)
1359 return udp_lib_setsockopt(sk, level, optname, optval, optlen,
1360 udp_v6_push_pending_frames);
1361 return compat_ipv6_setsockopt(sk, level, optname, optval, optlen);
1362}
1363#endif
1364
1365int udpv6_getsockopt(struct sock *sk, int level, int optname,
1366 char __user *optval, int __user *optlen)
1367{
1368 if (level == SOL_UDP || level == SOL_UDPLITE)
1369 return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1370 return ipv6_getsockopt(sk, level, optname, optval, optlen);
1371}
1372
1373#ifdef CONFIG_COMPAT
1374int compat_udpv6_getsockopt(struct sock *sk, int level, int optname,
1375 char __user *optval, int __user *optlen)
1376{
1377 if (level == SOL_UDP || level == SOL_UDPLITE)
1378 return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1379 return compat_ipv6_getsockopt(sk, level, optname, optval, optlen);
1380}
1381#endif
1382
1383static const struct inet6_protocol udpv6_protocol = {
1384 .handler = udpv6_rcv,
1385 .err_handler = udpv6_err,
1386 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1387};
1388
1389/* ------------------------------------------------------------------------ */
1390#ifdef CONFIG_PROC_FS
1391int udp6_seq_show(struct seq_file *seq, void *v)
1392{
1393 if (v == SEQ_START_TOKEN) {
1394 seq_puts(seq, IPV6_SEQ_DGRAM_HEADER);
1395 } else {
1396 int bucket = ((struct udp_iter_state *)seq->private)->bucket;
1397 struct inet_sock *inet = inet_sk(v);
1398 __u16 srcp = ntohs(inet->inet_sport);
1399 __u16 destp = ntohs(inet->inet_dport);
1400 ip6_dgram_sock_seq_show(seq, v, srcp, destp, bucket);
1401 }
1402 return 0;
1403}
1404
1405static const struct file_operations udp6_afinfo_seq_fops = {
1406 .owner = THIS_MODULE,
1407 .open = udp_seq_open,
1408 .read = seq_read,
1409 .llseek = seq_lseek,
1410 .release = seq_release_net
1411};
1412
1413static struct udp_seq_afinfo udp6_seq_afinfo = {
1414 .name = "udp6",
1415 .family = AF_INET6,
1416 .udp_table = &udp_table,
1417 .seq_fops = &udp6_afinfo_seq_fops,
1418 .seq_ops = {
1419 .show = udp6_seq_show,
1420 },
1421};
1422
1423int __net_init udp6_proc_init(struct net *net)
1424{
1425 return udp_proc_register(net, &udp6_seq_afinfo);
1426}
1427
1428void udp6_proc_exit(struct net *net) {
1429 udp_proc_unregister(net, &udp6_seq_afinfo);
1430}
1431#endif /* CONFIG_PROC_FS */
1432
1433void udp_v6_clear_sk(struct sock *sk, int size)
1434{
1435 struct inet_sock *inet = inet_sk(sk);
1436
1437 /* we do not want to clear pinet6 field, because of RCU lookups */
1438 sk_prot_clear_portaddr_nulls(sk, offsetof(struct inet_sock, pinet6));
1439
1440 size -= offsetof(struct inet_sock, pinet6) + sizeof(inet->pinet6);
1441 memset(&inet->pinet6 + 1, 0, size);
1442}
1443
1444/* ------------------------------------------------------------------------ */
1445
1446struct proto udpv6_prot = {
1447 .name = "UDPv6",
1448 .owner = THIS_MODULE,
1449 .close = udp_lib_close,
1450 .connect = ip6_datagram_connect,
1451 .disconnect = udp_disconnect,
1452 .ioctl = udp_ioctl,
1453 .destroy = udpv6_destroy_sock,
1454 .setsockopt = udpv6_setsockopt,
1455 .getsockopt = udpv6_getsockopt,
1456 .sendmsg = udpv6_sendmsg,
1457 .recvmsg = udpv6_recvmsg,
1458 .backlog_rcv = __udpv6_queue_rcv_skb,
1459 .hash = udp_lib_hash,
1460 .unhash = udp_lib_unhash,
1461 .rehash = udp_v6_rehash,
1462 .get_port = udp_v6_get_port,
1463 .memory_allocated = &udp_memory_allocated,
1464 .sysctl_mem = sysctl_udp_mem,
1465 .sysctl_wmem = &sysctl_udp_wmem_min,
1466 .sysctl_rmem = &sysctl_udp_rmem_min,
1467 .obj_size = sizeof(struct udp6_sock),
1468 .slab_flags = SLAB_DESTROY_BY_RCU,
1469 .h.udp_table = &udp_table,
1470#ifdef CONFIG_COMPAT
1471 .compat_setsockopt = compat_udpv6_setsockopt,
1472 .compat_getsockopt = compat_udpv6_getsockopt,
1473#endif
1474 .clear_sk = udp_v6_clear_sk,
1475};
1476
1477static struct inet_protosw udpv6_protosw = {
1478 .type = SOCK_DGRAM,
1479 .protocol = IPPROTO_UDP,
1480 .prot = &udpv6_prot,
1481 .ops = &inet6_dgram_ops,
1482 .no_check = UDP_CSUM_DEFAULT,
1483 .flags = INET_PROTOSW_PERMANENT,
1484};
1485
1486
1487int __init udpv6_init(void)
1488{
1489 int ret;
1490
1491 ret = inet6_add_protocol(&udpv6_protocol, IPPROTO_UDP);
1492 if (ret)
1493 goto out;
1494
1495 ret = inet6_register_protosw(&udpv6_protosw);
1496 if (ret)
1497 goto out_udpv6_protocol;
1498out:
1499 return ret;
1500
1501out_udpv6_protocol:
1502 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1503 goto out;
1504}
1505
1506void udpv6_exit(void)
1507{
1508 inet6_unregister_protosw(&udpv6_protosw);
1509 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1510}