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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 <linux/uaccess.h>
39
40#include <net/addrconf.h>
41#include <net/ndisc.h>
42#include <net/protocol.h>
43#include <net/transp_v6.h>
44#include <net/ip6_route.h>
45#include <net/raw.h>
46#include <net/tcp_states.h>
47#include <net/ip6_checksum.h>
48#include <net/xfrm.h>
49#include <net/inet_hashtables.h>
50#include <net/inet6_hashtables.h>
51#include <net/busy_poll.h>
52#include <net/sock_reuseport.h>
53
54#include <linux/proc_fs.h>
55#include <linux/seq_file.h>
56#include <trace/events/skb.h>
57#include "udp_impl.h"
58
59static bool udp6_lib_exact_dif_match(struct net *net, struct sk_buff *skb)
60{
61#if defined(CONFIG_NET_L3_MASTER_DEV)
62 if (!net->ipv4.sysctl_udp_l3mdev_accept &&
63 skb && ipv6_l3mdev_skb(IP6CB(skb)->flags))
64 return true;
65#endif
66 return false;
67}
68
69static u32 udp6_ehashfn(const struct net *net,
70 const struct in6_addr *laddr,
71 const u16 lport,
72 const struct in6_addr *faddr,
73 const __be16 fport)
74{
75 static u32 udp6_ehash_secret __read_mostly;
76 static u32 udp_ipv6_hash_secret __read_mostly;
77
78 u32 lhash, fhash;
79
80 net_get_random_once(&udp6_ehash_secret,
81 sizeof(udp6_ehash_secret));
82 net_get_random_once(&udp_ipv6_hash_secret,
83 sizeof(udp_ipv6_hash_secret));
84
85 lhash = (__force u32)laddr->s6_addr32[3];
86 fhash = __ipv6_addr_jhash(faddr, udp_ipv6_hash_secret);
87
88 return __inet6_ehashfn(lhash, lport, fhash, fport,
89 udp_ipv6_hash_secret + net_hash_mix(net));
90}
91
92int udp_v6_get_port(struct sock *sk, unsigned short snum)
93{
94 unsigned int hash2_nulladdr =
95 ipv6_portaddr_hash(sock_net(sk), &in6addr_any, snum);
96 unsigned int hash2_partial =
97 ipv6_portaddr_hash(sock_net(sk), &sk->sk_v6_rcv_saddr, 0);
98
99 /* precompute partial secondary hash */
100 udp_sk(sk)->udp_portaddr_hash = hash2_partial;
101 return udp_lib_get_port(sk, snum, hash2_nulladdr);
102}
103
104static void udp_v6_rehash(struct sock *sk)
105{
106 u16 new_hash = ipv6_portaddr_hash(sock_net(sk),
107 &sk->sk_v6_rcv_saddr,
108 inet_sk(sk)->inet_num);
109
110 udp_lib_rehash(sk, new_hash);
111}
112
113static int compute_score(struct sock *sk, struct net *net,
114 const struct in6_addr *saddr, __be16 sport,
115 const struct in6_addr *daddr, unsigned short hnum,
116 int dif, int sdif, bool exact_dif)
117{
118 int score;
119 struct inet_sock *inet;
120
121 if (!net_eq(sock_net(sk), net) ||
122 udp_sk(sk)->udp_port_hash != hnum ||
123 sk->sk_family != PF_INET6)
124 return -1;
125
126 score = 0;
127 inet = inet_sk(sk);
128
129 if (inet->inet_dport) {
130 if (inet->inet_dport != sport)
131 return -1;
132 score++;
133 }
134
135 if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr)) {
136 if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
137 return -1;
138 score++;
139 }
140
141 if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
142 if (!ipv6_addr_equal(&sk->sk_v6_daddr, saddr))
143 return -1;
144 score++;
145 }
146
147 if (sk->sk_bound_dev_if || exact_dif) {
148 bool dev_match = (sk->sk_bound_dev_if == dif ||
149 sk->sk_bound_dev_if == sdif);
150
151 if (!dev_match)
152 return -1;
153 if (sk->sk_bound_dev_if)
154 score++;
155 }
156
157 if (sk->sk_incoming_cpu == raw_smp_processor_id())
158 score++;
159
160 return score;
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, bool exact_dif,
168 struct udp_hslot *hslot2, struct sk_buff *skb)
169{
170 struct sock *sk, *result;
171 int score, badness;
172 u32 hash = 0;
173
174 result = NULL;
175 badness = -1;
176 udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) {
177 score = compute_score(sk, net, saddr, sport,
178 daddr, hnum, dif, sdif, exact_dif);
179 if (score > badness) {
180 if (sk->sk_reuseport) {
181 hash = udp6_ehashfn(net, daddr, hnum,
182 saddr, sport);
183
184 result = reuseport_select_sock(sk, hash, skb,
185 sizeof(struct udphdr));
186 if (result)
187 return result;
188 }
189 result = sk;
190 badness = score;
191 }
192 }
193 return result;
194}
195
196/* rcu_read_lock() must be held */
197struct sock *__udp6_lib_lookup(struct net *net,
198 const struct in6_addr *saddr, __be16 sport,
199 const struct in6_addr *daddr, __be16 dport,
200 int dif, int sdif, struct udp_table *udptable,
201 struct sk_buff *skb)
202{
203 struct sock *sk, *result;
204 unsigned short hnum = ntohs(dport);
205 unsigned int hash2, slot2, slot = udp_hashfn(net, hnum, udptable->mask);
206 struct udp_hslot *hslot2, *hslot = &udptable->hash[slot];
207 bool exact_dif = udp6_lib_exact_dif_match(net, skb);
208 int score, badness;
209 u32 hash = 0;
210
211 if (hslot->count > 10) {
212 hash2 = ipv6_portaddr_hash(net, daddr, hnum);
213 slot2 = hash2 & udptable->mask;
214 hslot2 = &udptable->hash2[slot2];
215 if (hslot->count < hslot2->count)
216 goto begin;
217
218 result = udp6_lib_lookup2(net, saddr, sport,
219 daddr, hnum, dif, sdif, exact_dif,
220 hslot2, skb);
221 if (!result) {
222 unsigned int old_slot2 = slot2;
223 hash2 = ipv6_portaddr_hash(net, &in6addr_any, hnum);
224 slot2 = hash2 & udptable->mask;
225 /* avoid searching the same slot again. */
226 if (unlikely(slot2 == old_slot2))
227 return result;
228
229 hslot2 = &udptable->hash2[slot2];
230 if (hslot->count < hslot2->count)
231 goto begin;
232
233 result = udp6_lib_lookup2(net, saddr, sport,
234 daddr, hnum, dif, sdif,
235 exact_dif, hslot2,
236 skb);
237 }
238 return result;
239 }
240begin:
241 result = NULL;
242 badness = -1;
243 sk_for_each_rcu(sk, &hslot->head) {
244 score = compute_score(sk, net, saddr, sport, daddr, hnum, dif,
245 sdif, exact_dif);
246 if (score > badness) {
247 if (sk->sk_reuseport) {
248 hash = udp6_ehashfn(net, daddr, hnum,
249 saddr, sport);
250 result = reuseport_select_sock(sk, hash, skb,
251 sizeof(struct udphdr));
252 if (result)
253 return result;
254 }
255 result = sk;
256 badness = score;
257 }
258 }
259 return result;
260}
261EXPORT_SYMBOL_GPL(__udp6_lib_lookup);
262
263static struct sock *__udp6_lib_lookup_skb(struct sk_buff *skb,
264 __be16 sport, __be16 dport,
265 struct udp_table *udptable)
266{
267 const struct ipv6hdr *iph = ipv6_hdr(skb);
268
269 return __udp6_lib_lookup(dev_net(skb->dev), &iph->saddr, sport,
270 &iph->daddr, dport, inet6_iif(skb),
271 inet6_sdif(skb), udptable, skb);
272}
273
274struct sock *udp6_lib_lookup_skb(struct sk_buff *skb,
275 __be16 sport, __be16 dport)
276{
277 const struct ipv6hdr *iph = ipv6_hdr(skb);
278
279 return __udp6_lib_lookup(dev_net(skb->dev), &iph->saddr, sport,
280 &iph->daddr, dport, inet6_iif(skb),
281 inet6_sdif(skb), &udp_table, skb);
282}
283EXPORT_SYMBOL_GPL(udp6_lib_lookup_skb);
284
285/* Must be called under rcu_read_lock().
286 * Does increment socket refcount.
287 */
288#if IS_ENABLED(CONFIG_NETFILTER_XT_MATCH_SOCKET) || \
289 IS_ENABLED(CONFIG_NETFILTER_XT_TARGET_TPROXY) || \
290 IS_ENABLED(CONFIG_NF_SOCKET_IPV6)
291struct sock *udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport,
292 const struct in6_addr *daddr, __be16 dport, int dif)
293{
294 struct sock *sk;
295
296 sk = __udp6_lib_lookup(net, saddr, sport, daddr, dport,
297 dif, 0, &udp_table, NULL);
298 if (sk && !refcount_inc_not_zero(&sk->sk_refcnt))
299 sk = NULL;
300 return sk;
301}
302EXPORT_SYMBOL_GPL(udp6_lib_lookup);
303#endif
304
305/* do not use the scratch area len for jumbogram: their length execeeds the
306 * scratch area space; note that the IP6CB flags is still in the first
307 * cacheline, so checking for jumbograms is cheap
308 */
309static int udp6_skb_len(struct sk_buff *skb)
310{
311 return unlikely(inet6_is_jumbogram(skb)) ? skb->len : udp_skb_len(skb);
312}
313
314/*
315 * This should be easy, if there is something there we
316 * return it, otherwise we block.
317 */
318
319int udpv6_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
320 int noblock, int flags, int *addr_len)
321{
322 struct ipv6_pinfo *np = inet6_sk(sk);
323 struct inet_sock *inet = inet_sk(sk);
324 struct sk_buff *skb;
325 unsigned int ulen, copied;
326 int peeked, peeking, off;
327 int err;
328 int is_udplite = IS_UDPLITE(sk);
329 bool checksum_valid = false;
330 int is_udp4;
331
332 if (flags & MSG_ERRQUEUE)
333 return ipv6_recv_error(sk, msg, len, addr_len);
334
335 if (np->rxpmtu && np->rxopt.bits.rxpmtu)
336 return ipv6_recv_rxpmtu(sk, msg, len, addr_len);
337
338try_again:
339 peeking = flags & MSG_PEEK;
340 off = sk_peek_offset(sk, flags);
341 skb = __skb_recv_udp(sk, flags, noblock, &peeked, &off, &err);
342 if (!skb)
343 return err;
344
345 ulen = udp6_skb_len(skb);
346 copied = len;
347 if (copied > ulen - off)
348 copied = ulen - off;
349 else if (copied < ulen)
350 msg->msg_flags |= MSG_TRUNC;
351
352 is_udp4 = (skb->protocol == htons(ETH_P_IP));
353
354 /*
355 * If checksum is needed at all, try to do it while copying the
356 * data. If the data is truncated, or if we only want a partial
357 * coverage checksum (UDP-Lite), do it before the copy.
358 */
359
360 if (copied < ulen || peeking ||
361 (is_udplite && UDP_SKB_CB(skb)->partial_cov)) {
362 checksum_valid = udp_skb_csum_unnecessary(skb) ||
363 !__udp_lib_checksum_complete(skb);
364 if (!checksum_valid)
365 goto csum_copy_err;
366 }
367
368 if (checksum_valid || udp_skb_csum_unnecessary(skb)) {
369 if (udp_skb_is_linear(skb))
370 err = copy_linear_skb(skb, copied, off, &msg->msg_iter);
371 else
372 err = skb_copy_datagram_msg(skb, off, msg, copied);
373 } else {
374 err = skb_copy_and_csum_datagram_msg(skb, off, msg);
375 if (err == -EINVAL)
376 goto csum_copy_err;
377 }
378 if (unlikely(err)) {
379 if (!peeked) {
380 atomic_inc(&sk->sk_drops);
381 if (is_udp4)
382 UDP_INC_STATS(sock_net(sk), UDP_MIB_INERRORS,
383 is_udplite);
384 else
385 UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS,
386 is_udplite);
387 }
388 kfree_skb(skb);
389 return err;
390 }
391 if (!peeked) {
392 if (is_udp4)
393 UDP_INC_STATS(sock_net(sk), UDP_MIB_INDATAGRAMS,
394 is_udplite);
395 else
396 UDP6_INC_STATS(sock_net(sk), UDP_MIB_INDATAGRAMS,
397 is_udplite);
398 }
399
400 sock_recv_ts_and_drops(msg, sk, skb);
401
402 /* Copy the address. */
403 if (msg->msg_name) {
404 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
405 sin6->sin6_family = AF_INET6;
406 sin6->sin6_port = udp_hdr(skb)->source;
407 sin6->sin6_flowinfo = 0;
408
409 if (is_udp4) {
410 ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
411 &sin6->sin6_addr);
412 sin6->sin6_scope_id = 0;
413 } else {
414 sin6->sin6_addr = ipv6_hdr(skb)->saddr;
415 sin6->sin6_scope_id =
416 ipv6_iface_scope_id(&sin6->sin6_addr,
417 inet6_iif(skb));
418 }
419 *addr_len = sizeof(*sin6);
420 }
421
422 if (np->rxopt.all)
423 ip6_datagram_recv_common_ctl(sk, msg, skb);
424
425 if (is_udp4) {
426 if (inet->cmsg_flags)
427 ip_cmsg_recv_offset(msg, sk, skb,
428 sizeof(struct udphdr), off);
429 } else {
430 if (np->rxopt.all)
431 ip6_datagram_recv_specific_ctl(sk, msg, skb);
432 }
433
434 err = copied;
435 if (flags & MSG_TRUNC)
436 err = ulen;
437
438 skb_consume_udp(sk, skb, peeking ? -err : err);
439 return err;
440
441csum_copy_err:
442 if (!__sk_queue_drop_skb(sk, &udp_sk(sk)->reader_queue, skb, flags,
443 udp_skb_destructor)) {
444 if (is_udp4) {
445 UDP_INC_STATS(sock_net(sk),
446 UDP_MIB_CSUMERRORS, is_udplite);
447 UDP_INC_STATS(sock_net(sk),
448 UDP_MIB_INERRORS, is_udplite);
449 } else {
450 UDP6_INC_STATS(sock_net(sk),
451 UDP_MIB_CSUMERRORS, is_udplite);
452 UDP6_INC_STATS(sock_net(sk),
453 UDP_MIB_INERRORS, is_udplite);
454 }
455 }
456 kfree_skb(skb);
457
458 /* starting over for a new packet, but check if we need to yield */
459 cond_resched();
460 msg->msg_flags &= ~MSG_TRUNC;
461 goto try_again;
462}
463
464void __udp6_lib_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
465 u8 type, u8 code, int offset, __be32 info,
466 struct udp_table *udptable)
467{
468 struct ipv6_pinfo *np;
469 const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data;
470 const struct in6_addr *saddr = &hdr->saddr;
471 const struct in6_addr *daddr = &hdr->daddr;
472 struct udphdr *uh = (struct udphdr *)(skb->data+offset);
473 struct sock *sk;
474 int harderr;
475 int err;
476 struct net *net = dev_net(skb->dev);
477
478 sk = __udp6_lib_lookup(net, daddr, uh->dest, saddr, uh->source,
479 inet6_iif(skb), 0, udptable, skb);
480 if (!sk) {
481 __ICMP6_INC_STATS(net, __in6_dev_get(skb->dev),
482 ICMP6_MIB_INERRORS);
483 return;
484 }
485
486 harderr = icmpv6_err_convert(type, code, &err);
487 np = inet6_sk(sk);
488
489 if (type == ICMPV6_PKT_TOOBIG) {
490 if (!ip6_sk_accept_pmtu(sk))
491 goto out;
492 ip6_sk_update_pmtu(skb, sk, info);
493 if (np->pmtudisc != IPV6_PMTUDISC_DONT)
494 harderr = 1;
495 }
496 if (type == NDISC_REDIRECT) {
497 ip6_sk_redirect(skb, sk);
498 goto out;
499 }
500
501 if (!np->recverr) {
502 if (!harderr || sk->sk_state != TCP_ESTABLISHED)
503 goto out;
504 } else {
505 ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1));
506 }
507
508 sk->sk_err = err;
509 sk->sk_error_report(sk);
510out:
511 return;
512}
513
514static int __udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
515{
516 int rc;
517
518 if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
519 sock_rps_save_rxhash(sk, skb);
520 sk_mark_napi_id(sk, skb);
521 sk_incoming_cpu_update(sk);
522 } else {
523 sk_mark_napi_id_once(sk, skb);
524 }
525
526 rc = __udp_enqueue_schedule_skb(sk, skb);
527 if (rc < 0) {
528 int is_udplite = IS_UDPLITE(sk);
529
530 /* Note that an ENOMEM error is charged twice */
531 if (rc == -ENOMEM)
532 UDP6_INC_STATS(sock_net(sk),
533 UDP_MIB_RCVBUFERRORS, is_udplite);
534 UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
535 kfree_skb(skb);
536 return -1;
537 }
538
539 return 0;
540}
541
542static __inline__ void udpv6_err(struct sk_buff *skb,
543 struct inet6_skb_parm *opt, u8 type,
544 u8 code, int offset, __be32 info)
545{
546 __udp6_lib_err(skb, opt, type, code, offset, info, &udp_table);
547}
548
549static struct static_key udpv6_encap_needed __read_mostly;
550void udpv6_encap_enable(void)
551{
552 static_key_enable(&udpv6_encap_needed);
553}
554EXPORT_SYMBOL(udpv6_encap_enable);
555
556static int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
557{
558 struct udp_sock *up = udp_sk(sk);
559 int is_udplite = IS_UDPLITE(sk);
560
561 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
562 goto drop;
563
564 if (static_key_false(&udpv6_encap_needed) && up->encap_type) {
565 int (*encap_rcv)(struct sock *sk, struct sk_buff *skb);
566
567 /*
568 * This is an encapsulation socket so pass the skb to
569 * the socket's udp_encap_rcv() hook. Otherwise, just
570 * fall through and pass this up the UDP socket.
571 * up->encap_rcv() returns the following value:
572 * =0 if skb was successfully passed to the encap
573 * handler or was discarded by it.
574 * >0 if skb should be passed on to UDP.
575 * <0 if skb should be resubmitted as proto -N
576 */
577
578 /* if we're overly short, let UDP handle it */
579 encap_rcv = READ_ONCE(up->encap_rcv);
580 if (encap_rcv) {
581 int ret;
582
583 /* Verify checksum before giving to encap */
584 if (udp_lib_checksum_complete(skb))
585 goto csum_error;
586
587 ret = encap_rcv(sk, skb);
588 if (ret <= 0) {
589 __UDP_INC_STATS(sock_net(sk),
590 UDP_MIB_INDATAGRAMS,
591 is_udplite);
592 return -ret;
593 }
594 }
595
596 /* FALLTHROUGH -- it's a UDP Packet */
597 }
598
599 /*
600 * UDP-Lite specific tests, ignored on UDP sockets (see net/ipv4/udp.c).
601 */
602 if ((is_udplite & UDPLITE_RECV_CC) && UDP_SKB_CB(skb)->partial_cov) {
603
604 if (up->pcrlen == 0) { /* full coverage was set */
605 net_dbg_ratelimited("UDPLITE6: partial coverage %d while full coverage %d requested\n",
606 UDP_SKB_CB(skb)->cscov, skb->len);
607 goto drop;
608 }
609 if (UDP_SKB_CB(skb)->cscov < up->pcrlen) {
610 net_dbg_ratelimited("UDPLITE6: coverage %d too small, need min %d\n",
611 UDP_SKB_CB(skb)->cscov, up->pcrlen);
612 goto drop;
613 }
614 }
615
616 prefetch(&sk->sk_rmem_alloc);
617 if (rcu_access_pointer(sk->sk_filter) &&
618 udp_lib_checksum_complete(skb))
619 goto csum_error;
620
621 if (sk_filter_trim_cap(sk, skb, sizeof(struct udphdr)))
622 goto drop;
623
624 udp_csum_pull_header(skb);
625
626 skb_dst_drop(skb);
627
628 return __udpv6_queue_rcv_skb(sk, skb);
629
630csum_error:
631 __UDP6_INC_STATS(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite);
632drop:
633 __UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
634 atomic_inc(&sk->sk_drops);
635 kfree_skb(skb);
636 return -1;
637}
638
639static bool __udp_v6_is_mcast_sock(struct net *net, struct sock *sk,
640 __be16 loc_port, const struct in6_addr *loc_addr,
641 __be16 rmt_port, const struct in6_addr *rmt_addr,
642 int dif, unsigned short hnum)
643{
644 struct inet_sock *inet = inet_sk(sk);
645
646 if (!net_eq(sock_net(sk), net))
647 return false;
648
649 if (udp_sk(sk)->udp_port_hash != hnum ||
650 sk->sk_family != PF_INET6 ||
651 (inet->inet_dport && inet->inet_dport != rmt_port) ||
652 (!ipv6_addr_any(&sk->sk_v6_daddr) &&
653 !ipv6_addr_equal(&sk->sk_v6_daddr, rmt_addr)) ||
654 (sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif) ||
655 (!ipv6_addr_any(&sk->sk_v6_rcv_saddr) &&
656 !ipv6_addr_equal(&sk->sk_v6_rcv_saddr, loc_addr)))
657 return false;
658 if (!inet6_mc_check(sk, loc_addr, rmt_addr))
659 return false;
660 return true;
661}
662
663static void udp6_csum_zero_error(struct sk_buff *skb)
664{
665 /* RFC 2460 section 8.1 says that we SHOULD log
666 * this error. Well, it is reasonable.
667 */
668 net_dbg_ratelimited("IPv6: udp checksum is 0 for [%pI6c]:%u->[%pI6c]:%u\n",
669 &ipv6_hdr(skb)->saddr, ntohs(udp_hdr(skb)->source),
670 &ipv6_hdr(skb)->daddr, ntohs(udp_hdr(skb)->dest));
671}
672
673/*
674 * Note: called only from the BH handler context,
675 * so we don't need to lock the hashes.
676 */
677static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
678 const struct in6_addr *saddr, const struct in6_addr *daddr,
679 struct udp_table *udptable, int proto)
680{
681 struct sock *sk, *first = NULL;
682 const struct udphdr *uh = udp_hdr(skb);
683 unsigned short hnum = ntohs(uh->dest);
684 struct udp_hslot *hslot = udp_hashslot(udptable, net, hnum);
685 unsigned int offset = offsetof(typeof(*sk), sk_node);
686 unsigned int hash2 = 0, hash2_any = 0, use_hash2 = (hslot->count > 10);
687 int dif = inet6_iif(skb);
688 struct hlist_node *node;
689 struct sk_buff *nskb;
690
691 if (use_hash2) {
692 hash2_any = ipv6_portaddr_hash(net, &in6addr_any, hnum) &
693 udptable->mask;
694 hash2 = ipv6_portaddr_hash(net, daddr, hnum) & udptable->mask;
695start_lookup:
696 hslot = &udptable->hash2[hash2];
697 offset = offsetof(typeof(*sk), __sk_common.skc_portaddr_node);
698 }
699
700 sk_for_each_entry_offset_rcu(sk, node, &hslot->head, offset) {
701 if (!__udp_v6_is_mcast_sock(net, sk, uh->dest, daddr,
702 uh->source, saddr, dif, hnum))
703 continue;
704 /* If zero checksum and no_check is not on for
705 * the socket then skip it.
706 */
707 if (!uh->check && !udp_sk(sk)->no_check6_rx)
708 continue;
709 if (!first) {
710 first = sk;
711 continue;
712 }
713 nskb = skb_clone(skb, GFP_ATOMIC);
714 if (unlikely(!nskb)) {
715 atomic_inc(&sk->sk_drops);
716 __UDP6_INC_STATS(net, UDP_MIB_RCVBUFERRORS,
717 IS_UDPLITE(sk));
718 __UDP6_INC_STATS(net, UDP_MIB_INERRORS,
719 IS_UDPLITE(sk));
720 continue;
721 }
722
723 if (udpv6_queue_rcv_skb(sk, nskb) > 0)
724 consume_skb(nskb);
725 }
726
727 /* Also lookup *:port if we are using hash2 and haven't done so yet. */
728 if (use_hash2 && hash2 != hash2_any) {
729 hash2 = hash2_any;
730 goto start_lookup;
731 }
732
733 if (first) {
734 if (udpv6_queue_rcv_skb(first, skb) > 0)
735 consume_skb(skb);
736 } else {
737 kfree_skb(skb);
738 __UDP6_INC_STATS(net, UDP_MIB_IGNOREDMULTI,
739 proto == IPPROTO_UDPLITE);
740 }
741 return 0;
742}
743
744static void udp6_sk_rx_dst_set(struct sock *sk, struct dst_entry *dst)
745{
746 if (udp_sk_rx_dst_set(sk, dst)) {
747 const struct rt6_info *rt = (const struct rt6_info *)dst;
748
749 inet6_sk(sk)->rx_dst_cookie = rt6_get_cookie(rt);
750 }
751}
752
753int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
754 int proto)
755{
756 const struct in6_addr *saddr, *daddr;
757 struct net *net = dev_net(skb->dev);
758 struct udphdr *uh;
759 struct sock *sk;
760 u32 ulen = 0;
761
762 if (!pskb_may_pull(skb, sizeof(struct udphdr)))
763 goto discard;
764
765 saddr = &ipv6_hdr(skb)->saddr;
766 daddr = &ipv6_hdr(skb)->daddr;
767 uh = udp_hdr(skb);
768
769 ulen = ntohs(uh->len);
770 if (ulen > skb->len)
771 goto short_packet;
772
773 if (proto == IPPROTO_UDP) {
774 /* UDP validates ulen. */
775
776 /* Check for jumbo payload */
777 if (ulen == 0)
778 ulen = skb->len;
779
780 if (ulen < sizeof(*uh))
781 goto short_packet;
782
783 if (ulen < skb->len) {
784 if (pskb_trim_rcsum(skb, ulen))
785 goto short_packet;
786 saddr = &ipv6_hdr(skb)->saddr;
787 daddr = &ipv6_hdr(skb)->daddr;
788 uh = udp_hdr(skb);
789 }
790 }
791
792 if (udp6_csum_init(skb, uh, proto))
793 goto csum_error;
794
795 /* Check if the socket is already available, e.g. due to early demux */
796 sk = skb_steal_sock(skb);
797 if (sk) {
798 struct dst_entry *dst = skb_dst(skb);
799 int ret;
800
801 if (unlikely(sk->sk_rx_dst != dst))
802 udp6_sk_rx_dst_set(sk, dst);
803
804 ret = udpv6_queue_rcv_skb(sk, skb);
805 sock_put(sk);
806
807 /* a return value > 0 means to resubmit the input */
808 if (ret > 0)
809 return ret;
810 return 0;
811 }
812
813 /*
814 * Multicast receive code
815 */
816 if (ipv6_addr_is_multicast(daddr))
817 return __udp6_lib_mcast_deliver(net, skb,
818 saddr, daddr, udptable, proto);
819
820 /* Unicast */
821 sk = __udp6_lib_lookup_skb(skb, uh->source, uh->dest, udptable);
822 if (sk) {
823 int ret;
824
825 if (!uh->check && !udp_sk(sk)->no_check6_rx) {
826 udp6_csum_zero_error(skb);
827 goto csum_error;
828 }
829
830 if (inet_get_convert_csum(sk) && uh->check && !IS_UDPLITE(sk))
831 skb_checksum_try_convert(skb, IPPROTO_UDP, uh->check,
832 ip6_compute_pseudo);
833
834 ret = udpv6_queue_rcv_skb(sk, skb);
835
836 /* a return value > 0 means to resubmit the input */
837 if (ret > 0)
838 return ret;
839
840 return 0;
841 }
842
843 if (!uh->check) {
844 udp6_csum_zero_error(skb);
845 goto csum_error;
846 }
847
848 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
849 goto discard;
850
851 if (udp_lib_checksum_complete(skb))
852 goto csum_error;
853
854 __UDP6_INC_STATS(net, UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE);
855 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
856
857 kfree_skb(skb);
858 return 0;
859
860short_packet:
861 net_dbg_ratelimited("UDP%sv6: short packet: From [%pI6c]:%u %d/%d to [%pI6c]:%u\n",
862 proto == IPPROTO_UDPLITE ? "-Lite" : "",
863 saddr, ntohs(uh->source),
864 ulen, skb->len,
865 daddr, ntohs(uh->dest));
866 goto discard;
867csum_error:
868 __UDP6_INC_STATS(net, UDP_MIB_CSUMERRORS, proto == IPPROTO_UDPLITE);
869discard:
870 __UDP6_INC_STATS(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE);
871 kfree_skb(skb);
872 return 0;
873}
874
875
876static struct sock *__udp6_lib_demux_lookup(struct net *net,
877 __be16 loc_port, const struct in6_addr *loc_addr,
878 __be16 rmt_port, const struct in6_addr *rmt_addr,
879 int dif, int sdif)
880{
881 unsigned short hnum = ntohs(loc_port);
882 unsigned int hash2 = ipv6_portaddr_hash(net, loc_addr, hnum);
883 unsigned int slot2 = hash2 & udp_table.mask;
884 struct udp_hslot *hslot2 = &udp_table.hash2[slot2];
885 const __portpair ports = INET_COMBINED_PORTS(rmt_port, hnum);
886 struct sock *sk;
887
888 udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) {
889 if (sk->sk_state == TCP_ESTABLISHED &&
890 INET6_MATCH(sk, net, rmt_addr, loc_addr, ports, dif, sdif))
891 return sk;
892 /* Only check first socket in chain */
893 break;
894 }
895 return NULL;
896}
897
898static void udp_v6_early_demux(struct sk_buff *skb)
899{
900 struct net *net = dev_net(skb->dev);
901 const struct udphdr *uh;
902 struct sock *sk;
903 struct dst_entry *dst;
904 int dif = skb->dev->ifindex;
905 int sdif = inet6_sdif(skb);
906
907 if (!pskb_may_pull(skb, skb_transport_offset(skb) +
908 sizeof(struct udphdr)))
909 return;
910
911 uh = udp_hdr(skb);
912
913 if (skb->pkt_type == PACKET_HOST)
914 sk = __udp6_lib_demux_lookup(net, uh->dest,
915 &ipv6_hdr(skb)->daddr,
916 uh->source, &ipv6_hdr(skb)->saddr,
917 dif, sdif);
918 else
919 return;
920
921 if (!sk || !refcount_inc_not_zero(&sk->sk_refcnt))
922 return;
923
924 skb->sk = sk;
925 skb->destructor = sock_efree;
926 dst = READ_ONCE(sk->sk_rx_dst);
927
928 if (dst)
929 dst = dst_check(dst, inet6_sk(sk)->rx_dst_cookie);
930 if (dst) {
931 /* set noref for now.
932 * any place which wants to hold dst has to call
933 * dst_hold_safe()
934 */
935 skb_dst_set_noref(skb, dst);
936 }
937}
938
939static __inline__ int udpv6_rcv(struct sk_buff *skb)
940{
941 return __udp6_lib_rcv(skb, &udp_table, IPPROTO_UDP);
942}
943
944/*
945 * Throw away all pending data and cancel the corking. Socket is locked.
946 */
947static void udp_v6_flush_pending_frames(struct sock *sk)
948{
949 struct udp_sock *up = udp_sk(sk);
950
951 if (up->pending == AF_INET)
952 udp_flush_pending_frames(sk);
953 else if (up->pending) {
954 up->len = 0;
955 up->pending = 0;
956 ip6_flush_pending_frames(sk);
957 }
958}
959
960static int udpv6_pre_connect(struct sock *sk, struct sockaddr *uaddr,
961 int addr_len)
962{
963 /* The following checks are replicated from __ip6_datagram_connect()
964 * and intended to prevent BPF program called below from accessing
965 * bytes that are out of the bound specified by user in addr_len.
966 */
967 if (uaddr->sa_family == AF_INET) {
968 if (__ipv6_only_sock(sk))
969 return -EAFNOSUPPORT;
970 return udp_pre_connect(sk, uaddr, addr_len);
971 }
972
973 if (addr_len < SIN6_LEN_RFC2133)
974 return -EINVAL;
975
976 return BPF_CGROUP_RUN_PROG_INET6_CONNECT_LOCK(sk, uaddr);
977}
978
979/**
980 * udp6_hwcsum_outgoing - handle outgoing HW checksumming
981 * @sk: socket we are sending on
982 * @skb: sk_buff containing the filled-in UDP header
983 * (checksum field must be zeroed out)
984 */
985static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb,
986 const struct in6_addr *saddr,
987 const struct in6_addr *daddr, int len)
988{
989 unsigned int offset;
990 struct udphdr *uh = udp_hdr(skb);
991 struct sk_buff *frags = skb_shinfo(skb)->frag_list;
992 __wsum csum = 0;
993
994 if (!frags) {
995 /* Only one fragment on the socket. */
996 skb->csum_start = skb_transport_header(skb) - skb->head;
997 skb->csum_offset = offsetof(struct udphdr, check);
998 uh->check = ~csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 0);
999 } else {
1000 /*
1001 * HW-checksum won't work as there are two or more
1002 * fragments on the socket so that all csums of sk_buffs
1003 * should be together
1004 */
1005 offset = skb_transport_offset(skb);
1006 skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
1007 csum = skb->csum;
1008
1009 skb->ip_summed = CHECKSUM_NONE;
1010
1011 do {
1012 csum = csum_add(csum, frags->csum);
1013 } while ((frags = frags->next));
1014
1015 uh->check = csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP,
1016 csum);
1017 if (uh->check == 0)
1018 uh->check = CSUM_MANGLED_0;
1019 }
1020}
1021
1022/*
1023 * Sending
1024 */
1025
1026static int udp_v6_send_skb(struct sk_buff *skb, struct flowi6 *fl6)
1027{
1028 struct sock *sk = skb->sk;
1029 struct udphdr *uh;
1030 int err = 0;
1031 int is_udplite = IS_UDPLITE(sk);
1032 __wsum csum = 0;
1033 int offset = skb_transport_offset(skb);
1034 int len = skb->len - offset;
1035
1036 /*
1037 * Create a UDP header
1038 */
1039 uh = udp_hdr(skb);
1040 uh->source = fl6->fl6_sport;
1041 uh->dest = fl6->fl6_dport;
1042 uh->len = htons(len);
1043 uh->check = 0;
1044
1045 if (is_udplite)
1046 csum = udplite_csum(skb);
1047 else if (udp_sk(sk)->no_check6_tx) { /* UDP csum disabled */
1048 skb->ip_summed = CHECKSUM_NONE;
1049 goto send;
1050 } else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */
1051 udp6_hwcsum_outgoing(sk, skb, &fl6->saddr, &fl6->daddr, len);
1052 goto send;
1053 } else
1054 csum = udp_csum(skb);
1055
1056 /* add protocol-dependent pseudo-header */
1057 uh->check = csum_ipv6_magic(&fl6->saddr, &fl6->daddr,
1058 len, fl6->flowi6_proto, csum);
1059 if (uh->check == 0)
1060 uh->check = CSUM_MANGLED_0;
1061
1062send:
1063 err = ip6_send_skb(skb);
1064 if (err) {
1065 if (err == -ENOBUFS && !inet6_sk(sk)->recverr) {
1066 UDP6_INC_STATS(sock_net(sk),
1067 UDP_MIB_SNDBUFERRORS, is_udplite);
1068 err = 0;
1069 }
1070 } else {
1071 UDP6_INC_STATS(sock_net(sk),
1072 UDP_MIB_OUTDATAGRAMS, is_udplite);
1073 }
1074 return err;
1075}
1076
1077static int udp_v6_push_pending_frames(struct sock *sk)
1078{
1079 struct sk_buff *skb;
1080 struct udp_sock *up = udp_sk(sk);
1081 struct flowi6 fl6;
1082 int err = 0;
1083
1084 if (up->pending == AF_INET)
1085 return udp_push_pending_frames(sk);
1086
1087 /* ip6_finish_skb will release the cork, so make a copy of
1088 * fl6 here.
1089 */
1090 fl6 = inet_sk(sk)->cork.fl.u.ip6;
1091
1092 skb = ip6_finish_skb(sk);
1093 if (!skb)
1094 goto out;
1095
1096 err = udp_v6_send_skb(skb, &fl6);
1097
1098out:
1099 up->len = 0;
1100 up->pending = 0;
1101 return err;
1102}
1103
1104int udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
1105{
1106 struct ipv6_txoptions opt_space;
1107 struct udp_sock *up = udp_sk(sk);
1108 struct inet_sock *inet = inet_sk(sk);
1109 struct ipv6_pinfo *np = inet6_sk(sk);
1110 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
1111 struct in6_addr *daddr, *final_p, final;
1112 struct ipv6_txoptions *opt = NULL;
1113 struct ipv6_txoptions *opt_to_free = NULL;
1114 struct ip6_flowlabel *flowlabel = NULL;
1115 struct flowi6 fl6;
1116 struct dst_entry *dst;
1117 struct ipcm6_cookie ipc6;
1118 int addr_len = msg->msg_namelen;
1119 bool connected = false;
1120 int ulen = len;
1121 int corkreq = up->corkflag || msg->msg_flags&MSG_MORE;
1122 int err;
1123 int is_udplite = IS_UDPLITE(sk);
1124 int (*getfrag)(void *, char *, int, int, int, struct sk_buff *);
1125 struct sockcm_cookie sockc;
1126
1127 ipc6.hlimit = -1;
1128 ipc6.tclass = -1;
1129 ipc6.dontfrag = -1;
1130 sockc.tsflags = sk->sk_tsflags;
1131
1132 /* destination address check */
1133 if (sin6) {
1134 if (addr_len < offsetof(struct sockaddr, sa_data))
1135 return -EINVAL;
1136
1137 switch (sin6->sin6_family) {
1138 case AF_INET6:
1139 if (addr_len < SIN6_LEN_RFC2133)
1140 return -EINVAL;
1141 daddr = &sin6->sin6_addr;
1142 if (ipv6_addr_any(daddr) &&
1143 ipv6_addr_v4mapped(&np->saddr))
1144 ipv6_addr_set_v4mapped(htonl(INADDR_LOOPBACK),
1145 daddr);
1146 break;
1147 case AF_INET:
1148 goto do_udp_sendmsg;
1149 case AF_UNSPEC:
1150 msg->msg_name = sin6 = NULL;
1151 msg->msg_namelen = addr_len = 0;
1152 daddr = NULL;
1153 break;
1154 default:
1155 return -EINVAL;
1156 }
1157 } else if (!up->pending) {
1158 if (sk->sk_state != TCP_ESTABLISHED)
1159 return -EDESTADDRREQ;
1160 daddr = &sk->sk_v6_daddr;
1161 } else
1162 daddr = NULL;
1163
1164 if (daddr) {
1165 if (ipv6_addr_v4mapped(daddr)) {
1166 struct sockaddr_in sin;
1167 sin.sin_family = AF_INET;
1168 sin.sin_port = sin6 ? sin6->sin6_port : inet->inet_dport;
1169 sin.sin_addr.s_addr = daddr->s6_addr32[3];
1170 msg->msg_name = &sin;
1171 msg->msg_namelen = sizeof(sin);
1172do_udp_sendmsg:
1173 if (__ipv6_only_sock(sk))
1174 return -ENETUNREACH;
1175 return udp_sendmsg(sk, msg, len);
1176 }
1177 }
1178
1179 if (up->pending == AF_INET)
1180 return udp_sendmsg(sk, msg, len);
1181
1182 /* Rough check on arithmetic overflow,
1183 better check is made in ip6_append_data().
1184 */
1185 if (len > INT_MAX - sizeof(struct udphdr))
1186 return -EMSGSIZE;
1187
1188 getfrag = is_udplite ? udplite_getfrag : ip_generic_getfrag;
1189 if (up->pending) {
1190 /*
1191 * There are pending frames.
1192 * The socket lock must be held while it's corked.
1193 */
1194 lock_sock(sk);
1195 if (likely(up->pending)) {
1196 if (unlikely(up->pending != AF_INET6)) {
1197 release_sock(sk);
1198 return -EAFNOSUPPORT;
1199 }
1200 dst = NULL;
1201 goto do_append_data;
1202 }
1203 release_sock(sk);
1204 }
1205 ulen += sizeof(struct udphdr);
1206
1207 memset(&fl6, 0, sizeof(fl6));
1208
1209 if (sin6) {
1210 if (sin6->sin6_port == 0)
1211 return -EINVAL;
1212
1213 fl6.fl6_dport = sin6->sin6_port;
1214 daddr = &sin6->sin6_addr;
1215
1216 if (np->sndflow) {
1217 fl6.flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK;
1218 if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) {
1219 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1220 if (!flowlabel)
1221 return -EINVAL;
1222 }
1223 }
1224
1225 /*
1226 * Otherwise it will be difficult to maintain
1227 * sk->sk_dst_cache.
1228 */
1229 if (sk->sk_state == TCP_ESTABLISHED &&
1230 ipv6_addr_equal(daddr, &sk->sk_v6_daddr))
1231 daddr = &sk->sk_v6_daddr;
1232
1233 if (addr_len >= sizeof(struct sockaddr_in6) &&
1234 sin6->sin6_scope_id &&
1235 __ipv6_addr_needs_scope_id(__ipv6_addr_type(daddr)))
1236 fl6.flowi6_oif = sin6->sin6_scope_id;
1237 } else {
1238 if (sk->sk_state != TCP_ESTABLISHED)
1239 return -EDESTADDRREQ;
1240
1241 fl6.fl6_dport = inet->inet_dport;
1242 daddr = &sk->sk_v6_daddr;
1243 fl6.flowlabel = np->flow_label;
1244 connected = true;
1245 }
1246
1247 if (!fl6.flowi6_oif)
1248 fl6.flowi6_oif = sk->sk_bound_dev_if;
1249
1250 if (!fl6.flowi6_oif)
1251 fl6.flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;
1252
1253 fl6.flowi6_mark = sk->sk_mark;
1254 fl6.flowi6_uid = sk->sk_uid;
1255
1256 if (msg->msg_controllen) {
1257 opt = &opt_space;
1258 memset(opt, 0, sizeof(struct ipv6_txoptions));
1259 opt->tot_len = sizeof(*opt);
1260 ipc6.opt = opt;
1261
1262 err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, &fl6, &ipc6, &sockc);
1263 if (err < 0) {
1264 fl6_sock_release(flowlabel);
1265 return err;
1266 }
1267 if ((fl6.flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) {
1268 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1269 if (!flowlabel)
1270 return -EINVAL;
1271 }
1272 if (!(opt->opt_nflen|opt->opt_flen))
1273 opt = NULL;
1274 connected = false;
1275 }
1276 if (!opt) {
1277 opt = txopt_get(np);
1278 opt_to_free = opt;
1279 }
1280 if (flowlabel)
1281 opt = fl6_merge_options(&opt_space, flowlabel, opt);
1282 opt = ipv6_fixup_options(&opt_space, opt);
1283 ipc6.opt = opt;
1284
1285 fl6.flowi6_proto = sk->sk_protocol;
1286 if (!ipv6_addr_any(daddr))
1287 fl6.daddr = *daddr;
1288 else
1289 fl6.daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */
1290 if (ipv6_addr_any(&fl6.saddr) && !ipv6_addr_any(&np->saddr))
1291 fl6.saddr = np->saddr;
1292 fl6.fl6_sport = inet->inet_sport;
1293
1294 final_p = fl6_update_dst(&fl6, opt, &final);
1295 if (final_p)
1296 connected = false;
1297
1298 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr)) {
1299 fl6.flowi6_oif = np->mcast_oif;
1300 connected = false;
1301 } else if (!fl6.flowi6_oif)
1302 fl6.flowi6_oif = np->ucast_oif;
1303
1304 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
1305
1306 if (ipc6.tclass < 0)
1307 ipc6.tclass = np->tclass;
1308
1309 fl6.flowlabel = ip6_make_flowinfo(ipc6.tclass, fl6.flowlabel);
1310
1311 dst = ip6_sk_dst_lookup_flow(sk, &fl6, final_p, connected);
1312 if (IS_ERR(dst)) {
1313 err = PTR_ERR(dst);
1314 dst = NULL;
1315 goto out;
1316 }
1317
1318 if (ipc6.hlimit < 0)
1319 ipc6.hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
1320
1321 if (msg->msg_flags&MSG_CONFIRM)
1322 goto do_confirm;
1323back_from_confirm:
1324
1325 /* Lockless fast path for the non-corking case */
1326 if (!corkreq) {
1327 struct sk_buff *skb;
1328
1329 skb = ip6_make_skb(sk, getfrag, msg, ulen,
1330 sizeof(struct udphdr), &ipc6,
1331 &fl6, (struct rt6_info *)dst,
1332 msg->msg_flags, &sockc);
1333 err = PTR_ERR(skb);
1334 if (!IS_ERR_OR_NULL(skb))
1335 err = udp_v6_send_skb(skb, &fl6);
1336 goto out;
1337 }
1338
1339 lock_sock(sk);
1340 if (unlikely(up->pending)) {
1341 /* The socket is already corked while preparing it. */
1342 /* ... which is an evident application bug. --ANK */
1343 release_sock(sk);
1344
1345 net_dbg_ratelimited("udp cork app bug 2\n");
1346 err = -EINVAL;
1347 goto out;
1348 }
1349
1350 up->pending = AF_INET6;
1351
1352do_append_data:
1353 if (ipc6.dontfrag < 0)
1354 ipc6.dontfrag = np->dontfrag;
1355 up->len += ulen;
1356 err = ip6_append_data(sk, getfrag, msg, ulen, sizeof(struct udphdr),
1357 &ipc6, &fl6, (struct rt6_info *)dst,
1358 corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags, &sockc);
1359 if (err)
1360 udp_v6_flush_pending_frames(sk);
1361 else if (!corkreq)
1362 err = udp_v6_push_pending_frames(sk);
1363 else if (unlikely(skb_queue_empty(&sk->sk_write_queue)))
1364 up->pending = 0;
1365
1366 if (err > 0)
1367 err = np->recverr ? net_xmit_errno(err) : 0;
1368 release_sock(sk);
1369
1370out:
1371 dst_release(dst);
1372 fl6_sock_release(flowlabel);
1373 txopt_put(opt_to_free);
1374 if (!err)
1375 return len;
1376 /*
1377 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space. Reporting
1378 * ENOBUFS might not be good (it's not tunable per se), but otherwise
1379 * we don't have a good statistic (IpOutDiscards but it can be too many
1380 * things). We could add another new stat but at least for now that
1381 * seems like overkill.
1382 */
1383 if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) {
1384 UDP6_INC_STATS(sock_net(sk),
1385 UDP_MIB_SNDBUFERRORS, is_udplite);
1386 }
1387 return err;
1388
1389do_confirm:
1390 if (msg->msg_flags & MSG_PROBE)
1391 dst_confirm_neigh(dst, &fl6.daddr);
1392 if (!(msg->msg_flags&MSG_PROBE) || len)
1393 goto back_from_confirm;
1394 err = 0;
1395 goto out;
1396}
1397
1398void udpv6_destroy_sock(struct sock *sk)
1399{
1400 struct udp_sock *up = udp_sk(sk);
1401 lock_sock(sk);
1402 udp_v6_flush_pending_frames(sk);
1403 release_sock(sk);
1404
1405 if (static_key_false(&udpv6_encap_needed) && up->encap_type) {
1406 void (*encap_destroy)(struct sock *sk);
1407 encap_destroy = READ_ONCE(up->encap_destroy);
1408 if (encap_destroy)
1409 encap_destroy(sk);
1410 }
1411
1412 inet6_destroy_sock(sk);
1413}
1414
1415/*
1416 * Socket option code for UDP
1417 */
1418int udpv6_setsockopt(struct sock *sk, int level, int optname,
1419 char __user *optval, unsigned int optlen)
1420{
1421 if (level == SOL_UDP || level == SOL_UDPLITE)
1422 return udp_lib_setsockopt(sk, level, optname, optval, optlen,
1423 udp_v6_push_pending_frames);
1424 return ipv6_setsockopt(sk, level, optname, optval, optlen);
1425}
1426
1427#ifdef CONFIG_COMPAT
1428int compat_udpv6_setsockopt(struct sock *sk, int level, int optname,
1429 char __user *optval, unsigned int optlen)
1430{
1431 if (level == SOL_UDP || level == SOL_UDPLITE)
1432 return udp_lib_setsockopt(sk, level, optname, optval, optlen,
1433 udp_v6_push_pending_frames);
1434 return compat_ipv6_setsockopt(sk, level, optname, optval, optlen);
1435}
1436#endif
1437
1438int udpv6_getsockopt(struct sock *sk, int level, int optname,
1439 char __user *optval, int __user *optlen)
1440{
1441 if (level == SOL_UDP || level == SOL_UDPLITE)
1442 return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1443 return ipv6_getsockopt(sk, level, optname, optval, optlen);
1444}
1445
1446#ifdef CONFIG_COMPAT
1447int compat_udpv6_getsockopt(struct sock *sk, int level, int optname,
1448 char __user *optval, int __user *optlen)
1449{
1450 if (level == SOL_UDP || level == SOL_UDPLITE)
1451 return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1452 return compat_ipv6_getsockopt(sk, level, optname, optval, optlen);
1453}
1454#endif
1455
1456/* thinking of making this const? Don't.
1457 * early_demux can change based on sysctl.
1458 */
1459static struct inet6_protocol udpv6_protocol = {
1460 .early_demux = udp_v6_early_demux,
1461 .early_demux_handler = udp_v6_early_demux,
1462 .handler = udpv6_rcv,
1463 .err_handler = udpv6_err,
1464 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1465};
1466
1467/* ------------------------------------------------------------------------ */
1468#ifdef CONFIG_PROC_FS
1469int udp6_seq_show(struct seq_file *seq, void *v)
1470{
1471 if (v == SEQ_START_TOKEN) {
1472 seq_puts(seq, IPV6_SEQ_DGRAM_HEADER);
1473 } else {
1474 int bucket = ((struct udp_iter_state *)seq->private)->bucket;
1475 struct inet_sock *inet = inet_sk(v);
1476 __u16 srcp = ntohs(inet->inet_sport);
1477 __u16 destp = ntohs(inet->inet_dport);
1478 ip6_dgram_sock_seq_show(seq, v, srcp, destp, bucket);
1479 }
1480 return 0;
1481}
1482
1483static const struct file_operations udp6_afinfo_seq_fops = {
1484 .open = udp_seq_open,
1485 .read = seq_read,
1486 .llseek = seq_lseek,
1487 .release = seq_release_net
1488};
1489
1490static struct udp_seq_afinfo udp6_seq_afinfo = {
1491 .name = "udp6",
1492 .family = AF_INET6,
1493 .udp_table = &udp_table,
1494 .seq_fops = &udp6_afinfo_seq_fops,
1495 .seq_ops = {
1496 .show = udp6_seq_show,
1497 },
1498};
1499
1500int __net_init udp6_proc_init(struct net *net)
1501{
1502 return udp_proc_register(net, &udp6_seq_afinfo);
1503}
1504
1505void udp6_proc_exit(struct net *net)
1506{
1507 udp_proc_unregister(net, &udp6_seq_afinfo);
1508}
1509#endif /* CONFIG_PROC_FS */
1510
1511/* ------------------------------------------------------------------------ */
1512
1513struct proto udpv6_prot = {
1514 .name = "UDPv6",
1515 .owner = THIS_MODULE,
1516 .close = udp_lib_close,
1517 .pre_connect = udpv6_pre_connect,
1518 .connect = ip6_datagram_connect,
1519 .disconnect = udp_disconnect,
1520 .ioctl = udp_ioctl,
1521 .init = udp_init_sock,
1522 .destroy = udpv6_destroy_sock,
1523 .setsockopt = udpv6_setsockopt,
1524 .getsockopt = udpv6_getsockopt,
1525 .sendmsg = udpv6_sendmsg,
1526 .recvmsg = udpv6_recvmsg,
1527 .release_cb = ip6_datagram_release_cb,
1528 .hash = udp_lib_hash,
1529 .unhash = udp_lib_unhash,
1530 .rehash = udp_v6_rehash,
1531 .get_port = udp_v6_get_port,
1532 .memory_allocated = &udp_memory_allocated,
1533 .sysctl_mem = sysctl_udp_mem,
1534 .sysctl_wmem_offset = offsetof(struct net, ipv4.sysctl_udp_wmem_min),
1535 .sysctl_rmem_offset = offsetof(struct net, ipv4.sysctl_udp_rmem_min),
1536 .obj_size = sizeof(struct udp6_sock),
1537 .h.udp_table = &udp_table,
1538#ifdef CONFIG_COMPAT
1539 .compat_setsockopt = compat_udpv6_setsockopt,
1540 .compat_getsockopt = compat_udpv6_getsockopt,
1541#endif
1542 .diag_destroy = udp_abort,
1543};
1544
1545static struct inet_protosw udpv6_protosw = {
1546 .type = SOCK_DGRAM,
1547 .protocol = IPPROTO_UDP,
1548 .prot = &udpv6_prot,
1549 .ops = &inet6_dgram_ops,
1550 .flags = INET_PROTOSW_PERMANENT,
1551};
1552
1553int __init udpv6_init(void)
1554{
1555 int ret;
1556
1557 ret = inet6_add_protocol(&udpv6_protocol, IPPROTO_UDP);
1558 if (ret)
1559 goto out;
1560
1561 ret = inet6_register_protosw(&udpv6_protosw);
1562 if (ret)
1563 goto out_udpv6_protocol;
1564out:
1565 return ret;
1566
1567out_udpv6_protocol:
1568 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1569 goto out;
1570}
1571
1572void udpv6_exit(void)
1573{
1574 inet6_unregister_protosw(&udpv6_protosw);
1575 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1576}
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 score++;
137
138 if (READ_ONCE(sk->sk_incoming_cpu) == raw_smp_processor_id())
139 score++;
140
141 return score;
142}
143
144/* called with rcu_read_lock() */
145static struct sock *udp6_lib_lookup2(struct net *net,
146 const struct in6_addr *saddr, __be16 sport,
147 const struct in6_addr *daddr, unsigned int hnum,
148 int dif, int sdif, struct udp_hslot *hslot2,
149 struct sk_buff *skb)
150{
151 struct sock *sk, *result;
152 int score, badness;
153 u32 hash = 0;
154
155 result = NULL;
156 badness = -1;
157 udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) {
158 score = compute_score(sk, net, saddr, sport,
159 daddr, hnum, dif, sdif);
160 if (score > badness) {
161 if (sk->sk_reuseport &&
162 sk->sk_state != TCP_ESTABLISHED) {
163 hash = udp6_ehashfn(net, daddr, hnum,
164 saddr, sport);
165
166 result = reuseport_select_sock(sk, hash, skb,
167 sizeof(struct udphdr));
168 if (result && !reuseport_has_conns(sk, false))
169 return result;
170 }
171 result = sk;
172 badness = score;
173 }
174 }
175 return result;
176}
177
178/* rcu_read_lock() must be held */
179struct sock *__udp6_lib_lookup(struct net *net,
180 const struct in6_addr *saddr, __be16 sport,
181 const struct in6_addr *daddr, __be16 dport,
182 int dif, int sdif, struct udp_table *udptable,
183 struct sk_buff *skb)
184{
185 unsigned short hnum = ntohs(dport);
186 unsigned int hash2, slot2;
187 struct udp_hslot *hslot2;
188 struct sock *result;
189
190 hash2 = ipv6_portaddr_hash(net, daddr, hnum);
191 slot2 = hash2 & udptable->mask;
192 hslot2 = &udptable->hash2[slot2];
193
194 result = udp6_lib_lookup2(net, saddr, sport,
195 daddr, hnum, dif, sdif,
196 hslot2, skb);
197 if (!result) {
198 hash2 = ipv6_portaddr_hash(net, &in6addr_any, hnum);
199 slot2 = hash2 & udptable->mask;
200
201 hslot2 = &udptable->hash2[slot2];
202
203 result = udp6_lib_lookup2(net, saddr, sport,
204 &in6addr_any, hnum, dif, sdif,
205 hslot2, skb);
206 }
207 if (IS_ERR(result))
208 return NULL;
209 return result;
210}
211EXPORT_SYMBOL_GPL(__udp6_lib_lookup);
212
213static struct sock *__udp6_lib_lookup_skb(struct sk_buff *skb,
214 __be16 sport, __be16 dport,
215 struct udp_table *udptable)
216{
217 const struct ipv6hdr *iph = ipv6_hdr(skb);
218
219 return __udp6_lib_lookup(dev_net(skb->dev), &iph->saddr, sport,
220 &iph->daddr, dport, inet6_iif(skb),
221 inet6_sdif(skb), udptable, skb);
222}
223
224struct sock *udp6_lib_lookup_skb(struct sk_buff *skb,
225 __be16 sport, __be16 dport)
226{
227 const struct ipv6hdr *iph = ipv6_hdr(skb);
228
229 return __udp6_lib_lookup(dev_net(skb->dev), &iph->saddr, sport,
230 &iph->daddr, dport, inet6_iif(skb),
231 inet6_sdif(skb), &udp_table, NULL);
232}
233EXPORT_SYMBOL_GPL(udp6_lib_lookup_skb);
234
235/* Must be called under rcu_read_lock().
236 * Does increment socket refcount.
237 */
238#if IS_ENABLED(CONFIG_NF_TPROXY_IPV6) || IS_ENABLED(CONFIG_NF_SOCKET_IPV6)
239struct sock *udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport,
240 const struct in6_addr *daddr, __be16 dport, int dif)
241{
242 struct sock *sk;
243
244 sk = __udp6_lib_lookup(net, saddr, sport, daddr, dport,
245 dif, 0, &udp_table, NULL);
246 if (sk && !refcount_inc_not_zero(&sk->sk_refcnt))
247 sk = NULL;
248 return sk;
249}
250EXPORT_SYMBOL_GPL(udp6_lib_lookup);
251#endif
252
253/* do not use the scratch area len for jumbogram: their length execeeds the
254 * scratch area space; note that the IP6CB flags is still in the first
255 * cacheline, so checking for jumbograms is cheap
256 */
257static int udp6_skb_len(struct sk_buff *skb)
258{
259 return unlikely(inet6_is_jumbogram(skb)) ? skb->len : udp_skb_len(skb);
260}
261
262/*
263 * This should be easy, if there is something there we
264 * return it, otherwise we block.
265 */
266
267int udpv6_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
268 int noblock, int flags, int *addr_len)
269{
270 struct ipv6_pinfo *np = inet6_sk(sk);
271 struct inet_sock *inet = inet_sk(sk);
272 struct sk_buff *skb;
273 unsigned int ulen, copied;
274 int off, err, peeking = flags & MSG_PEEK;
275 int is_udplite = IS_UDPLITE(sk);
276 struct udp_mib __percpu *mib;
277 bool checksum_valid = false;
278 int is_udp4;
279
280 if (flags & MSG_ERRQUEUE)
281 return ipv6_recv_error(sk, msg, len, addr_len);
282
283 if (np->rxpmtu && np->rxopt.bits.rxpmtu)
284 return ipv6_recv_rxpmtu(sk, msg, len, addr_len);
285
286try_again:
287 off = sk_peek_offset(sk, flags);
288 skb = __skb_recv_udp(sk, flags, noblock, &off, &err);
289 if (!skb)
290 return err;
291
292 ulen = udp6_skb_len(skb);
293 copied = len;
294 if (copied > ulen - off)
295 copied = ulen - off;
296 else if (copied < ulen)
297 msg->msg_flags |= MSG_TRUNC;
298
299 is_udp4 = (skb->protocol == htons(ETH_P_IP));
300 mib = __UDPX_MIB(sk, is_udp4);
301
302 /*
303 * If checksum is needed at all, try to do it while copying the
304 * data. If the data is truncated, or if we only want a partial
305 * coverage checksum (UDP-Lite), do it before the copy.
306 */
307
308 if (copied < ulen || peeking ||
309 (is_udplite && UDP_SKB_CB(skb)->partial_cov)) {
310 checksum_valid = udp_skb_csum_unnecessary(skb) ||
311 !__udp_lib_checksum_complete(skb);
312 if (!checksum_valid)
313 goto csum_copy_err;
314 }
315
316 if (checksum_valid || udp_skb_csum_unnecessary(skb)) {
317 if (udp_skb_is_linear(skb))
318 err = copy_linear_skb(skb, copied, off, &msg->msg_iter);
319 else
320 err = skb_copy_datagram_msg(skb, off, msg, copied);
321 } else {
322 err = skb_copy_and_csum_datagram_msg(skb, off, msg);
323 if (err == -EINVAL)
324 goto csum_copy_err;
325 }
326 if (unlikely(err)) {
327 if (!peeking) {
328 atomic_inc(&sk->sk_drops);
329 SNMP_INC_STATS(mib, UDP_MIB_INERRORS);
330 }
331 kfree_skb(skb);
332 return err;
333 }
334 if (!peeking)
335 SNMP_INC_STATS(mib, UDP_MIB_INDATAGRAMS);
336
337 sock_recv_ts_and_drops(msg, sk, skb);
338
339 /* Copy the address. */
340 if (msg->msg_name) {
341 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
342 sin6->sin6_family = AF_INET6;
343 sin6->sin6_port = udp_hdr(skb)->source;
344 sin6->sin6_flowinfo = 0;
345
346 if (is_udp4) {
347 ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
348 &sin6->sin6_addr);
349 sin6->sin6_scope_id = 0;
350 } else {
351 sin6->sin6_addr = ipv6_hdr(skb)->saddr;
352 sin6->sin6_scope_id =
353 ipv6_iface_scope_id(&sin6->sin6_addr,
354 inet6_iif(skb));
355 }
356 *addr_len = sizeof(*sin6);
357
358 if (cgroup_bpf_enabled)
359 BPF_CGROUP_RUN_PROG_UDP6_RECVMSG_LOCK(sk,
360 (struct sockaddr *)sin6);
361 }
362
363 if (udp_sk(sk)->gro_enabled)
364 udp_cmsg_recv(msg, sk, skb);
365
366 if (np->rxopt.all)
367 ip6_datagram_recv_common_ctl(sk, msg, skb);
368
369 if (is_udp4) {
370 if (inet->cmsg_flags)
371 ip_cmsg_recv_offset(msg, sk, skb,
372 sizeof(struct udphdr), off);
373 } else {
374 if (np->rxopt.all)
375 ip6_datagram_recv_specific_ctl(sk, msg, skb);
376 }
377
378 err = copied;
379 if (flags & MSG_TRUNC)
380 err = ulen;
381
382 skb_consume_udp(sk, skb, peeking ? -err : err);
383 return err;
384
385csum_copy_err:
386 if (!__sk_queue_drop_skb(sk, &udp_sk(sk)->reader_queue, skb, flags,
387 udp_skb_destructor)) {
388 SNMP_INC_STATS(mib, UDP_MIB_CSUMERRORS);
389 SNMP_INC_STATS(mib, UDP_MIB_INERRORS);
390 }
391 kfree_skb(skb);
392
393 /* starting over for a new packet, but check if we need to yield */
394 cond_resched();
395 msg->msg_flags &= ~MSG_TRUNC;
396 goto try_again;
397}
398
399DEFINE_STATIC_KEY_FALSE(udpv6_encap_needed_key);
400void udpv6_encap_enable(void)
401{
402 static_branch_inc(&udpv6_encap_needed_key);
403}
404EXPORT_SYMBOL(udpv6_encap_enable);
405
406/* Handler for tunnels with arbitrary destination ports: no socket lookup, go
407 * through error handlers in encapsulations looking for a match.
408 */
409static int __udp6_lib_err_encap_no_sk(struct sk_buff *skb,
410 struct inet6_skb_parm *opt,
411 u8 type, u8 code, int offset, __be32 info)
412{
413 int i;
414
415 for (i = 0; i < MAX_IPTUN_ENCAP_OPS; i++) {
416 int (*handler)(struct sk_buff *skb, struct inet6_skb_parm *opt,
417 u8 type, u8 code, int offset, __be32 info);
418 const struct ip6_tnl_encap_ops *encap;
419
420 encap = rcu_dereference(ip6tun_encaps[i]);
421 if (!encap)
422 continue;
423 handler = encap->err_handler;
424 if (handler && !handler(skb, opt, type, code, offset, info))
425 return 0;
426 }
427
428 return -ENOENT;
429}
430
431/* Try to match ICMP errors to UDP tunnels by looking up a socket without
432 * reversing source and destination port: this will match tunnels that force the
433 * same destination port on both endpoints (e.g. VXLAN, GENEVE). Note that
434 * lwtunnels might actually break this assumption by being configured with
435 * different destination ports on endpoints, in this case we won't be able to
436 * trace ICMP messages back to them.
437 *
438 * If this doesn't match any socket, probe tunnels with arbitrary destination
439 * ports (e.g. FoU, GUE): there, the receiving socket is useless, as the port
440 * we've sent packets to won't necessarily match the local destination port.
441 *
442 * Then ask the tunnel implementation to match the error against a valid
443 * association.
444 *
445 * Return an error if we can't find a match, the socket if we need further
446 * processing, zero otherwise.
447 */
448static struct sock *__udp6_lib_err_encap(struct net *net,
449 const struct ipv6hdr *hdr, int offset,
450 struct udphdr *uh,
451 struct udp_table *udptable,
452 struct sk_buff *skb,
453 struct inet6_skb_parm *opt,
454 u8 type, u8 code, __be32 info)
455{
456 int network_offset, transport_offset;
457 struct sock *sk;
458
459 network_offset = skb_network_offset(skb);
460 transport_offset = skb_transport_offset(skb);
461
462 /* Network header needs to point to the outer IPv6 header inside ICMP */
463 skb_reset_network_header(skb);
464
465 /* Transport header needs to point to the UDP header */
466 skb_set_transport_header(skb, offset);
467
468 sk = __udp6_lib_lookup(net, &hdr->daddr, uh->source,
469 &hdr->saddr, uh->dest,
470 inet6_iif(skb), 0, udptable, skb);
471 if (sk) {
472 int (*lookup)(struct sock *sk, struct sk_buff *skb);
473 struct udp_sock *up = udp_sk(sk);
474
475 lookup = READ_ONCE(up->encap_err_lookup);
476 if (!lookup || lookup(sk, skb))
477 sk = NULL;
478 }
479
480 if (!sk) {
481 sk = ERR_PTR(__udp6_lib_err_encap_no_sk(skb, opt, type, code,
482 offset, info));
483 }
484
485 skb_set_transport_header(skb, transport_offset);
486 skb_set_network_header(skb, network_offset);
487
488 return sk;
489}
490
491int __udp6_lib_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
492 u8 type, u8 code, int offset, __be32 info,
493 struct udp_table *udptable)
494{
495 struct ipv6_pinfo *np;
496 const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data;
497 const struct in6_addr *saddr = &hdr->saddr;
498 const struct in6_addr *daddr = &hdr->daddr;
499 struct udphdr *uh = (struct udphdr *)(skb->data+offset);
500 bool tunnel = false;
501 struct sock *sk;
502 int harderr;
503 int err;
504 struct net *net = dev_net(skb->dev);
505
506 sk = __udp6_lib_lookup(net, daddr, uh->dest, saddr, uh->source,
507 inet6_iif(skb), inet6_sdif(skb), udptable, NULL);
508 if (!sk) {
509 /* No socket for error: try tunnels before discarding */
510 sk = ERR_PTR(-ENOENT);
511 if (static_branch_unlikely(&udpv6_encap_needed_key)) {
512 sk = __udp6_lib_err_encap(net, hdr, offset, uh,
513 udptable, skb,
514 opt, type, code, info);
515 if (!sk)
516 return 0;
517 }
518
519 if (IS_ERR(sk)) {
520 __ICMP6_INC_STATS(net, __in6_dev_get(skb->dev),
521 ICMP6_MIB_INERRORS);
522 return PTR_ERR(sk);
523 }
524
525 tunnel = true;
526 }
527
528 harderr = icmpv6_err_convert(type, code, &err);
529 np = inet6_sk(sk);
530
531 if (type == ICMPV6_PKT_TOOBIG) {
532 if (!ip6_sk_accept_pmtu(sk))
533 goto out;
534 ip6_sk_update_pmtu(skb, sk, info);
535 if (np->pmtudisc != IPV6_PMTUDISC_DONT)
536 harderr = 1;
537 }
538 if (type == NDISC_REDIRECT) {
539 if (tunnel) {
540 ip6_redirect(skb, sock_net(sk), inet6_iif(skb),
541 sk->sk_mark, sk->sk_uid);
542 } else {
543 ip6_sk_redirect(skb, sk);
544 }
545 goto out;
546 }
547
548 /* Tunnels don't have an application socket: don't pass errors back */
549 if (tunnel)
550 goto out;
551
552 if (!np->recverr) {
553 if (!harderr || sk->sk_state != TCP_ESTABLISHED)
554 goto out;
555 } else {
556 ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1));
557 }
558
559 sk->sk_err = err;
560 sk->sk_error_report(sk);
561out:
562 return 0;
563}
564
565static int __udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
566{
567 int rc;
568
569 if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
570 sock_rps_save_rxhash(sk, skb);
571 sk_mark_napi_id(sk, skb);
572 sk_incoming_cpu_update(sk);
573 } else {
574 sk_mark_napi_id_once(sk, skb);
575 }
576
577 rc = __udp_enqueue_schedule_skb(sk, skb);
578 if (rc < 0) {
579 int is_udplite = IS_UDPLITE(sk);
580
581 /* Note that an ENOMEM error is charged twice */
582 if (rc == -ENOMEM)
583 UDP6_INC_STATS(sock_net(sk),
584 UDP_MIB_RCVBUFERRORS, is_udplite);
585 UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
586 kfree_skb(skb);
587 return -1;
588 }
589
590 return 0;
591}
592
593static __inline__ int udpv6_err(struct sk_buff *skb,
594 struct inet6_skb_parm *opt, u8 type,
595 u8 code, int offset, __be32 info)
596{
597 return __udp6_lib_err(skb, opt, type, code, offset, info, &udp_table);
598}
599
600static int udpv6_queue_rcv_one_skb(struct sock *sk, struct sk_buff *skb)
601{
602 struct udp_sock *up = udp_sk(sk);
603 int is_udplite = IS_UDPLITE(sk);
604
605 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
606 goto drop;
607
608 if (static_branch_unlikely(&udpv6_encap_needed_key) && up->encap_type) {
609 int (*encap_rcv)(struct sock *sk, struct sk_buff *skb);
610
611 /*
612 * This is an encapsulation socket so pass the skb to
613 * the socket's udp_encap_rcv() hook. Otherwise, just
614 * fall through and pass this up the UDP socket.
615 * up->encap_rcv() returns the following value:
616 * =0 if skb was successfully passed to the encap
617 * handler or was discarded by it.
618 * >0 if skb should be passed on to UDP.
619 * <0 if skb should be resubmitted as proto -N
620 */
621
622 /* if we're overly short, let UDP handle it */
623 encap_rcv = READ_ONCE(up->encap_rcv);
624 if (encap_rcv) {
625 int ret;
626
627 /* Verify checksum before giving to encap */
628 if (udp_lib_checksum_complete(skb))
629 goto csum_error;
630
631 ret = encap_rcv(sk, skb);
632 if (ret <= 0) {
633 __UDP_INC_STATS(sock_net(sk),
634 UDP_MIB_INDATAGRAMS,
635 is_udplite);
636 return -ret;
637 }
638 }
639
640 /* FALLTHROUGH -- it's a UDP Packet */
641 }
642
643 /*
644 * UDP-Lite specific tests, ignored on UDP sockets (see net/ipv4/udp.c).
645 */
646 if ((is_udplite & UDPLITE_RECV_CC) && UDP_SKB_CB(skb)->partial_cov) {
647
648 if (up->pcrlen == 0) { /* full coverage was set */
649 net_dbg_ratelimited("UDPLITE6: partial coverage %d while full coverage %d requested\n",
650 UDP_SKB_CB(skb)->cscov, skb->len);
651 goto drop;
652 }
653 if (UDP_SKB_CB(skb)->cscov < up->pcrlen) {
654 net_dbg_ratelimited("UDPLITE6: coverage %d too small, need min %d\n",
655 UDP_SKB_CB(skb)->cscov, up->pcrlen);
656 goto drop;
657 }
658 }
659
660 prefetch(&sk->sk_rmem_alloc);
661 if (rcu_access_pointer(sk->sk_filter) &&
662 udp_lib_checksum_complete(skb))
663 goto csum_error;
664
665 if (sk_filter_trim_cap(sk, skb, sizeof(struct udphdr)))
666 goto drop;
667
668 udp_csum_pull_header(skb);
669
670 skb_dst_drop(skb);
671
672 return __udpv6_queue_rcv_skb(sk, skb);
673
674csum_error:
675 __UDP6_INC_STATS(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite);
676drop:
677 __UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
678 atomic_inc(&sk->sk_drops);
679 kfree_skb(skb);
680 return -1;
681}
682
683static int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
684{
685 struct sk_buff *next, *segs;
686 int ret;
687
688 if (likely(!udp_unexpected_gso(sk, skb)))
689 return udpv6_queue_rcv_one_skb(sk, skb);
690
691 __skb_push(skb, -skb_mac_offset(skb));
692 segs = udp_rcv_segment(sk, skb, false);
693 for (skb = segs; skb; skb = next) {
694 next = skb->next;
695 __skb_pull(skb, skb_transport_offset(skb));
696
697 ret = udpv6_queue_rcv_one_skb(sk, skb);
698 if (ret > 0)
699 ip6_protocol_deliver_rcu(dev_net(skb->dev), skb, ret,
700 true);
701 }
702 return 0;
703}
704
705static bool __udp_v6_is_mcast_sock(struct net *net, struct sock *sk,
706 __be16 loc_port, const struct in6_addr *loc_addr,
707 __be16 rmt_port, const struct in6_addr *rmt_addr,
708 int dif, int sdif, unsigned short hnum)
709{
710 struct inet_sock *inet = inet_sk(sk);
711
712 if (!net_eq(sock_net(sk), net))
713 return false;
714
715 if (udp_sk(sk)->udp_port_hash != hnum ||
716 sk->sk_family != PF_INET6 ||
717 (inet->inet_dport && inet->inet_dport != rmt_port) ||
718 (!ipv6_addr_any(&sk->sk_v6_daddr) &&
719 !ipv6_addr_equal(&sk->sk_v6_daddr, rmt_addr)) ||
720 !udp_sk_bound_dev_eq(net, sk->sk_bound_dev_if, dif, sdif) ||
721 (!ipv6_addr_any(&sk->sk_v6_rcv_saddr) &&
722 !ipv6_addr_equal(&sk->sk_v6_rcv_saddr, loc_addr)))
723 return false;
724 if (!inet6_mc_check(sk, loc_addr, rmt_addr))
725 return false;
726 return true;
727}
728
729static void udp6_csum_zero_error(struct sk_buff *skb)
730{
731 /* RFC 2460 section 8.1 says that we SHOULD log
732 * this error. Well, it is reasonable.
733 */
734 net_dbg_ratelimited("IPv6: udp checksum is 0 for [%pI6c]:%u->[%pI6c]:%u\n",
735 &ipv6_hdr(skb)->saddr, ntohs(udp_hdr(skb)->source),
736 &ipv6_hdr(skb)->daddr, ntohs(udp_hdr(skb)->dest));
737}
738
739/*
740 * Note: called only from the BH handler context,
741 * so we don't need to lock the hashes.
742 */
743static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
744 const struct in6_addr *saddr, const struct in6_addr *daddr,
745 struct udp_table *udptable, int proto)
746{
747 struct sock *sk, *first = NULL;
748 const struct udphdr *uh = udp_hdr(skb);
749 unsigned short hnum = ntohs(uh->dest);
750 struct udp_hslot *hslot = udp_hashslot(udptable, net, hnum);
751 unsigned int offset = offsetof(typeof(*sk), sk_node);
752 unsigned int hash2 = 0, hash2_any = 0, use_hash2 = (hslot->count > 10);
753 int dif = inet6_iif(skb);
754 int sdif = inet6_sdif(skb);
755 struct hlist_node *node;
756 struct sk_buff *nskb;
757
758 if (use_hash2) {
759 hash2_any = ipv6_portaddr_hash(net, &in6addr_any, hnum) &
760 udptable->mask;
761 hash2 = ipv6_portaddr_hash(net, daddr, hnum) & udptable->mask;
762start_lookup:
763 hslot = &udptable->hash2[hash2];
764 offset = offsetof(typeof(*sk), __sk_common.skc_portaddr_node);
765 }
766
767 sk_for_each_entry_offset_rcu(sk, node, &hslot->head, offset) {
768 if (!__udp_v6_is_mcast_sock(net, sk, uh->dest, daddr,
769 uh->source, saddr, dif, sdif,
770 hnum))
771 continue;
772 /* If zero checksum and no_check is not on for
773 * the socket then skip it.
774 */
775 if (!uh->check && !udp_sk(sk)->no_check6_rx)
776 continue;
777 if (!first) {
778 first = sk;
779 continue;
780 }
781 nskb = skb_clone(skb, GFP_ATOMIC);
782 if (unlikely(!nskb)) {
783 atomic_inc(&sk->sk_drops);
784 __UDP6_INC_STATS(net, UDP_MIB_RCVBUFERRORS,
785 IS_UDPLITE(sk));
786 __UDP6_INC_STATS(net, UDP_MIB_INERRORS,
787 IS_UDPLITE(sk));
788 continue;
789 }
790
791 if (udpv6_queue_rcv_skb(sk, nskb) > 0)
792 consume_skb(nskb);
793 }
794
795 /* Also lookup *:port if we are using hash2 and haven't done so yet. */
796 if (use_hash2 && hash2 != hash2_any) {
797 hash2 = hash2_any;
798 goto start_lookup;
799 }
800
801 if (first) {
802 if (udpv6_queue_rcv_skb(first, skb) > 0)
803 consume_skb(skb);
804 } else {
805 kfree_skb(skb);
806 __UDP6_INC_STATS(net, UDP_MIB_IGNOREDMULTI,
807 proto == IPPROTO_UDPLITE);
808 }
809 return 0;
810}
811
812static void udp6_sk_rx_dst_set(struct sock *sk, struct dst_entry *dst)
813{
814 if (udp_sk_rx_dst_set(sk, dst)) {
815 const struct rt6_info *rt = (const struct rt6_info *)dst;
816
817 inet6_sk(sk)->rx_dst_cookie = rt6_get_cookie(rt);
818 }
819}
820
821/* wrapper for udp_queue_rcv_skb tacking care of csum conversion and
822 * return code conversion for ip layer consumption
823 */
824static int udp6_unicast_rcv_skb(struct sock *sk, struct sk_buff *skb,
825 struct udphdr *uh)
826{
827 int ret;
828
829 if (inet_get_convert_csum(sk) && uh->check && !IS_UDPLITE(sk))
830 skb_checksum_try_convert(skb, IPPROTO_UDP, ip6_compute_pseudo);
831
832 ret = udpv6_queue_rcv_skb(sk, skb);
833
834 /* a return value > 0 means to resubmit the input */
835 if (ret > 0)
836 return ret;
837 return 0;
838}
839
840int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
841 int proto)
842{
843 const struct in6_addr *saddr, *daddr;
844 struct net *net = dev_net(skb->dev);
845 struct udphdr *uh;
846 struct sock *sk;
847 u32 ulen = 0;
848
849 if (!pskb_may_pull(skb, sizeof(struct udphdr)))
850 goto discard;
851
852 saddr = &ipv6_hdr(skb)->saddr;
853 daddr = &ipv6_hdr(skb)->daddr;
854 uh = udp_hdr(skb);
855
856 ulen = ntohs(uh->len);
857 if (ulen > skb->len)
858 goto short_packet;
859
860 if (proto == IPPROTO_UDP) {
861 /* UDP validates ulen. */
862
863 /* Check for jumbo payload */
864 if (ulen == 0)
865 ulen = skb->len;
866
867 if (ulen < sizeof(*uh))
868 goto short_packet;
869
870 if (ulen < skb->len) {
871 if (pskb_trim_rcsum(skb, ulen))
872 goto short_packet;
873 saddr = &ipv6_hdr(skb)->saddr;
874 daddr = &ipv6_hdr(skb)->daddr;
875 uh = udp_hdr(skb);
876 }
877 }
878
879 if (udp6_csum_init(skb, uh, proto))
880 goto csum_error;
881
882 /* Check if the socket is already available, e.g. due to early demux */
883 sk = skb_steal_sock(skb);
884 if (sk) {
885 struct dst_entry *dst = skb_dst(skb);
886 int ret;
887
888 if (unlikely(sk->sk_rx_dst != dst))
889 udp6_sk_rx_dst_set(sk, dst);
890
891 if (!uh->check && !udp_sk(sk)->no_check6_rx) {
892 sock_put(sk);
893 goto report_csum_error;
894 }
895
896 ret = udp6_unicast_rcv_skb(sk, skb, uh);
897 sock_put(sk);
898 return ret;
899 }
900
901 /*
902 * Multicast receive code
903 */
904 if (ipv6_addr_is_multicast(daddr))
905 return __udp6_lib_mcast_deliver(net, skb,
906 saddr, daddr, udptable, proto);
907
908 /* Unicast */
909 sk = __udp6_lib_lookup_skb(skb, uh->source, uh->dest, udptable);
910 if (sk) {
911 if (!uh->check && !udp_sk(sk)->no_check6_rx)
912 goto report_csum_error;
913 return udp6_unicast_rcv_skb(sk, skb, uh);
914 }
915
916 if (!uh->check)
917 goto report_csum_error;
918
919 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
920 goto discard;
921
922 if (udp_lib_checksum_complete(skb))
923 goto csum_error;
924
925 __UDP6_INC_STATS(net, UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE);
926 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
927
928 kfree_skb(skb);
929 return 0;
930
931short_packet:
932 net_dbg_ratelimited("UDP%sv6: short packet: From [%pI6c]:%u %d/%d to [%pI6c]:%u\n",
933 proto == IPPROTO_UDPLITE ? "-Lite" : "",
934 saddr, ntohs(uh->source),
935 ulen, skb->len,
936 daddr, ntohs(uh->dest));
937 goto discard;
938
939report_csum_error:
940 udp6_csum_zero_error(skb);
941csum_error:
942 __UDP6_INC_STATS(net, UDP_MIB_CSUMERRORS, proto == IPPROTO_UDPLITE);
943discard:
944 __UDP6_INC_STATS(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE);
945 kfree_skb(skb);
946 return 0;
947}
948
949
950static struct sock *__udp6_lib_demux_lookup(struct net *net,
951 __be16 loc_port, const struct in6_addr *loc_addr,
952 __be16 rmt_port, const struct in6_addr *rmt_addr,
953 int dif, int sdif)
954{
955 unsigned short hnum = ntohs(loc_port);
956 unsigned int hash2 = ipv6_portaddr_hash(net, loc_addr, hnum);
957 unsigned int slot2 = hash2 & udp_table.mask;
958 struct udp_hslot *hslot2 = &udp_table.hash2[slot2];
959 const __portpair ports = INET_COMBINED_PORTS(rmt_port, hnum);
960 struct sock *sk;
961
962 udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) {
963 if (sk->sk_state == TCP_ESTABLISHED &&
964 INET6_MATCH(sk, net, rmt_addr, loc_addr, ports, dif, sdif))
965 return sk;
966 /* Only check first socket in chain */
967 break;
968 }
969 return NULL;
970}
971
972INDIRECT_CALLABLE_SCOPE void udp_v6_early_demux(struct sk_buff *skb)
973{
974 struct net *net = dev_net(skb->dev);
975 const struct udphdr *uh;
976 struct sock *sk;
977 struct dst_entry *dst;
978 int dif = skb->dev->ifindex;
979 int sdif = inet6_sdif(skb);
980
981 if (!pskb_may_pull(skb, skb_transport_offset(skb) +
982 sizeof(struct udphdr)))
983 return;
984
985 uh = udp_hdr(skb);
986
987 if (skb->pkt_type == PACKET_HOST)
988 sk = __udp6_lib_demux_lookup(net, uh->dest,
989 &ipv6_hdr(skb)->daddr,
990 uh->source, &ipv6_hdr(skb)->saddr,
991 dif, sdif);
992 else
993 return;
994
995 if (!sk || !refcount_inc_not_zero(&sk->sk_refcnt))
996 return;
997
998 skb->sk = sk;
999 skb->destructor = sock_efree;
1000 dst = READ_ONCE(sk->sk_rx_dst);
1001
1002 if (dst)
1003 dst = dst_check(dst, inet6_sk(sk)->rx_dst_cookie);
1004 if (dst) {
1005 /* set noref for now.
1006 * any place which wants to hold dst has to call
1007 * dst_hold_safe()
1008 */
1009 skb_dst_set_noref(skb, dst);
1010 }
1011}
1012
1013INDIRECT_CALLABLE_SCOPE int udpv6_rcv(struct sk_buff *skb)
1014{
1015 return __udp6_lib_rcv(skb, &udp_table, IPPROTO_UDP);
1016}
1017
1018/*
1019 * Throw away all pending data and cancel the corking. Socket is locked.
1020 */
1021static void udp_v6_flush_pending_frames(struct sock *sk)
1022{
1023 struct udp_sock *up = udp_sk(sk);
1024
1025 if (up->pending == AF_INET)
1026 udp_flush_pending_frames(sk);
1027 else if (up->pending) {
1028 up->len = 0;
1029 up->pending = 0;
1030 ip6_flush_pending_frames(sk);
1031 }
1032}
1033
1034static int udpv6_pre_connect(struct sock *sk, struct sockaddr *uaddr,
1035 int addr_len)
1036{
1037 if (addr_len < offsetofend(struct sockaddr, sa_family))
1038 return -EINVAL;
1039 /* The following checks are replicated from __ip6_datagram_connect()
1040 * and intended to prevent BPF program called below from accessing
1041 * bytes that are out of the bound specified by user in addr_len.
1042 */
1043 if (uaddr->sa_family == AF_INET) {
1044 if (__ipv6_only_sock(sk))
1045 return -EAFNOSUPPORT;
1046 return udp_pre_connect(sk, uaddr, addr_len);
1047 }
1048
1049 if (addr_len < SIN6_LEN_RFC2133)
1050 return -EINVAL;
1051
1052 return BPF_CGROUP_RUN_PROG_INET6_CONNECT_LOCK(sk, uaddr);
1053}
1054
1055/**
1056 * udp6_hwcsum_outgoing - handle outgoing HW checksumming
1057 * @sk: socket we are sending on
1058 * @skb: sk_buff containing the filled-in UDP header
1059 * (checksum field must be zeroed out)
1060 */
1061static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb,
1062 const struct in6_addr *saddr,
1063 const struct in6_addr *daddr, int len)
1064{
1065 unsigned int offset;
1066 struct udphdr *uh = udp_hdr(skb);
1067 struct sk_buff *frags = skb_shinfo(skb)->frag_list;
1068 __wsum csum = 0;
1069
1070 if (!frags) {
1071 /* Only one fragment on the socket. */
1072 skb->csum_start = skb_transport_header(skb) - skb->head;
1073 skb->csum_offset = offsetof(struct udphdr, check);
1074 uh->check = ~csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 0);
1075 } else {
1076 /*
1077 * HW-checksum won't work as there are two or more
1078 * fragments on the socket so that all csums of sk_buffs
1079 * should be together
1080 */
1081 offset = skb_transport_offset(skb);
1082 skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
1083 csum = skb->csum;
1084
1085 skb->ip_summed = CHECKSUM_NONE;
1086
1087 do {
1088 csum = csum_add(csum, frags->csum);
1089 } while ((frags = frags->next));
1090
1091 uh->check = csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP,
1092 csum);
1093 if (uh->check == 0)
1094 uh->check = CSUM_MANGLED_0;
1095 }
1096}
1097
1098/*
1099 * Sending
1100 */
1101
1102static int udp_v6_send_skb(struct sk_buff *skb, struct flowi6 *fl6,
1103 struct inet_cork *cork)
1104{
1105 struct sock *sk = skb->sk;
1106 struct udphdr *uh;
1107 int err = 0;
1108 int is_udplite = IS_UDPLITE(sk);
1109 __wsum csum = 0;
1110 int offset = skb_transport_offset(skb);
1111 int len = skb->len - offset;
1112 int datalen = len - sizeof(*uh);
1113
1114 /*
1115 * Create a UDP header
1116 */
1117 uh = udp_hdr(skb);
1118 uh->source = fl6->fl6_sport;
1119 uh->dest = fl6->fl6_dport;
1120 uh->len = htons(len);
1121 uh->check = 0;
1122
1123 if (cork->gso_size) {
1124 const int hlen = skb_network_header_len(skb) +
1125 sizeof(struct udphdr);
1126
1127 if (hlen + cork->gso_size > cork->fragsize) {
1128 kfree_skb(skb);
1129 return -EINVAL;
1130 }
1131 if (skb->len > cork->gso_size * UDP_MAX_SEGMENTS) {
1132 kfree_skb(skb);
1133 return -EINVAL;
1134 }
1135 if (udp_sk(sk)->no_check6_tx) {
1136 kfree_skb(skb);
1137 return -EINVAL;
1138 }
1139 if (skb->ip_summed != CHECKSUM_PARTIAL || is_udplite ||
1140 dst_xfrm(skb_dst(skb))) {
1141 kfree_skb(skb);
1142 return -EIO;
1143 }
1144
1145 if (datalen > cork->gso_size) {
1146 skb_shinfo(skb)->gso_size = cork->gso_size;
1147 skb_shinfo(skb)->gso_type = SKB_GSO_UDP_L4;
1148 skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(datalen,
1149 cork->gso_size);
1150 }
1151 goto csum_partial;
1152 }
1153
1154 if (is_udplite)
1155 csum = udplite_csum(skb);
1156 else if (udp_sk(sk)->no_check6_tx) { /* UDP csum disabled */
1157 skb->ip_summed = CHECKSUM_NONE;
1158 goto send;
1159 } else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */
1160csum_partial:
1161 udp6_hwcsum_outgoing(sk, skb, &fl6->saddr, &fl6->daddr, len);
1162 goto send;
1163 } else
1164 csum = udp_csum(skb);
1165
1166 /* add protocol-dependent pseudo-header */
1167 uh->check = csum_ipv6_magic(&fl6->saddr, &fl6->daddr,
1168 len, fl6->flowi6_proto, csum);
1169 if (uh->check == 0)
1170 uh->check = CSUM_MANGLED_0;
1171
1172send:
1173 err = ip6_send_skb(skb);
1174 if (err) {
1175 if (err == -ENOBUFS && !inet6_sk(sk)->recverr) {
1176 UDP6_INC_STATS(sock_net(sk),
1177 UDP_MIB_SNDBUFERRORS, is_udplite);
1178 err = 0;
1179 }
1180 } else {
1181 UDP6_INC_STATS(sock_net(sk),
1182 UDP_MIB_OUTDATAGRAMS, is_udplite);
1183 }
1184 return err;
1185}
1186
1187static int udp_v6_push_pending_frames(struct sock *sk)
1188{
1189 struct sk_buff *skb;
1190 struct udp_sock *up = udp_sk(sk);
1191 struct flowi6 fl6;
1192 int err = 0;
1193
1194 if (up->pending == AF_INET)
1195 return udp_push_pending_frames(sk);
1196
1197 /* ip6_finish_skb will release the cork, so make a copy of
1198 * fl6 here.
1199 */
1200 fl6 = inet_sk(sk)->cork.fl.u.ip6;
1201
1202 skb = ip6_finish_skb(sk);
1203 if (!skb)
1204 goto out;
1205
1206 err = udp_v6_send_skb(skb, &fl6, &inet_sk(sk)->cork.base);
1207
1208out:
1209 up->len = 0;
1210 up->pending = 0;
1211 return err;
1212}
1213
1214int udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
1215{
1216 struct ipv6_txoptions opt_space;
1217 struct udp_sock *up = udp_sk(sk);
1218 struct inet_sock *inet = inet_sk(sk);
1219 struct ipv6_pinfo *np = inet6_sk(sk);
1220 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
1221 struct in6_addr *daddr, *final_p, final;
1222 struct ipv6_txoptions *opt = NULL;
1223 struct ipv6_txoptions *opt_to_free = NULL;
1224 struct ip6_flowlabel *flowlabel = NULL;
1225 struct flowi6 fl6;
1226 struct dst_entry *dst;
1227 struct ipcm6_cookie ipc6;
1228 int addr_len = msg->msg_namelen;
1229 bool connected = false;
1230 int ulen = len;
1231 int corkreq = up->corkflag || msg->msg_flags&MSG_MORE;
1232 int err;
1233 int is_udplite = IS_UDPLITE(sk);
1234 int (*getfrag)(void *, char *, int, int, int, struct sk_buff *);
1235
1236 ipcm6_init(&ipc6);
1237 ipc6.gso_size = up->gso_size;
1238 ipc6.sockc.tsflags = sk->sk_tsflags;
1239 ipc6.sockc.mark = sk->sk_mark;
1240
1241 /* destination address check */
1242 if (sin6) {
1243 if (addr_len < offsetof(struct sockaddr, sa_data))
1244 return -EINVAL;
1245
1246 switch (sin6->sin6_family) {
1247 case AF_INET6:
1248 if (addr_len < SIN6_LEN_RFC2133)
1249 return -EINVAL;
1250 daddr = &sin6->sin6_addr;
1251 if (ipv6_addr_any(daddr) &&
1252 ipv6_addr_v4mapped(&np->saddr))
1253 ipv6_addr_set_v4mapped(htonl(INADDR_LOOPBACK),
1254 daddr);
1255 break;
1256 case AF_INET:
1257 goto do_udp_sendmsg;
1258 case AF_UNSPEC:
1259 msg->msg_name = sin6 = NULL;
1260 msg->msg_namelen = addr_len = 0;
1261 daddr = NULL;
1262 break;
1263 default:
1264 return -EINVAL;
1265 }
1266 } else if (!up->pending) {
1267 if (sk->sk_state != TCP_ESTABLISHED)
1268 return -EDESTADDRREQ;
1269 daddr = &sk->sk_v6_daddr;
1270 } else
1271 daddr = NULL;
1272
1273 if (daddr) {
1274 if (ipv6_addr_v4mapped(daddr)) {
1275 struct sockaddr_in sin;
1276 sin.sin_family = AF_INET;
1277 sin.sin_port = sin6 ? sin6->sin6_port : inet->inet_dport;
1278 sin.sin_addr.s_addr = daddr->s6_addr32[3];
1279 msg->msg_name = &sin;
1280 msg->msg_namelen = sizeof(sin);
1281do_udp_sendmsg:
1282 if (__ipv6_only_sock(sk))
1283 return -ENETUNREACH;
1284 return udp_sendmsg(sk, msg, len);
1285 }
1286 }
1287
1288 if (up->pending == AF_INET)
1289 return udp_sendmsg(sk, msg, len);
1290
1291 /* Rough check on arithmetic overflow,
1292 better check is made in ip6_append_data().
1293 */
1294 if (len > INT_MAX - sizeof(struct udphdr))
1295 return -EMSGSIZE;
1296
1297 getfrag = is_udplite ? udplite_getfrag : ip_generic_getfrag;
1298 if (up->pending) {
1299 /*
1300 * There are pending frames.
1301 * The socket lock must be held while it's corked.
1302 */
1303 lock_sock(sk);
1304 if (likely(up->pending)) {
1305 if (unlikely(up->pending != AF_INET6)) {
1306 release_sock(sk);
1307 return -EAFNOSUPPORT;
1308 }
1309 dst = NULL;
1310 goto do_append_data;
1311 }
1312 release_sock(sk);
1313 }
1314 ulen += sizeof(struct udphdr);
1315
1316 memset(&fl6, 0, sizeof(fl6));
1317
1318 if (sin6) {
1319 if (sin6->sin6_port == 0)
1320 return -EINVAL;
1321
1322 fl6.fl6_dport = sin6->sin6_port;
1323 daddr = &sin6->sin6_addr;
1324
1325 if (np->sndflow) {
1326 fl6.flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK;
1327 if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) {
1328 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1329 if (IS_ERR(flowlabel))
1330 return -EINVAL;
1331 }
1332 }
1333
1334 /*
1335 * Otherwise it will be difficult to maintain
1336 * sk->sk_dst_cache.
1337 */
1338 if (sk->sk_state == TCP_ESTABLISHED &&
1339 ipv6_addr_equal(daddr, &sk->sk_v6_daddr))
1340 daddr = &sk->sk_v6_daddr;
1341
1342 if (addr_len >= sizeof(struct sockaddr_in6) &&
1343 sin6->sin6_scope_id &&
1344 __ipv6_addr_needs_scope_id(__ipv6_addr_type(daddr)))
1345 fl6.flowi6_oif = sin6->sin6_scope_id;
1346 } else {
1347 if (sk->sk_state != TCP_ESTABLISHED)
1348 return -EDESTADDRREQ;
1349
1350 fl6.fl6_dport = inet->inet_dport;
1351 daddr = &sk->sk_v6_daddr;
1352 fl6.flowlabel = np->flow_label;
1353 connected = true;
1354 }
1355
1356 if (!fl6.flowi6_oif)
1357 fl6.flowi6_oif = sk->sk_bound_dev_if;
1358
1359 if (!fl6.flowi6_oif)
1360 fl6.flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;
1361
1362 fl6.flowi6_mark = ipc6.sockc.mark;
1363 fl6.flowi6_uid = sk->sk_uid;
1364
1365 if (msg->msg_controllen) {
1366 opt = &opt_space;
1367 memset(opt, 0, sizeof(struct ipv6_txoptions));
1368 opt->tot_len = sizeof(*opt);
1369 ipc6.opt = opt;
1370
1371 err = udp_cmsg_send(sk, msg, &ipc6.gso_size);
1372 if (err > 0)
1373 err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, &fl6,
1374 &ipc6);
1375 if (err < 0) {
1376 fl6_sock_release(flowlabel);
1377 return err;
1378 }
1379 if ((fl6.flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) {
1380 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1381 if (IS_ERR(flowlabel))
1382 return -EINVAL;
1383 }
1384 if (!(opt->opt_nflen|opt->opt_flen))
1385 opt = NULL;
1386 connected = false;
1387 }
1388 if (!opt) {
1389 opt = txopt_get(np);
1390 opt_to_free = opt;
1391 }
1392 if (flowlabel)
1393 opt = fl6_merge_options(&opt_space, flowlabel, opt);
1394 opt = ipv6_fixup_options(&opt_space, opt);
1395 ipc6.opt = opt;
1396
1397 fl6.flowi6_proto = sk->sk_protocol;
1398 fl6.daddr = *daddr;
1399 if (ipv6_addr_any(&fl6.saddr) && !ipv6_addr_any(&np->saddr))
1400 fl6.saddr = np->saddr;
1401 fl6.fl6_sport = inet->inet_sport;
1402
1403 if (cgroup_bpf_enabled && !connected) {
1404 err = BPF_CGROUP_RUN_PROG_UDP6_SENDMSG_LOCK(sk,
1405 (struct sockaddr *)sin6, &fl6.saddr);
1406 if (err)
1407 goto out_no_dst;
1408 if (sin6) {
1409 if (ipv6_addr_v4mapped(&sin6->sin6_addr)) {
1410 /* BPF program rewrote IPv6-only by IPv4-mapped
1411 * IPv6. It's currently unsupported.
1412 */
1413 err = -ENOTSUPP;
1414 goto out_no_dst;
1415 }
1416 if (sin6->sin6_port == 0) {
1417 /* BPF program set invalid port. Reject it. */
1418 err = -EINVAL;
1419 goto out_no_dst;
1420 }
1421 fl6.fl6_dport = sin6->sin6_port;
1422 fl6.daddr = sin6->sin6_addr;
1423 }
1424 }
1425
1426 if (ipv6_addr_any(&fl6.daddr))
1427 fl6.daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */
1428
1429 final_p = fl6_update_dst(&fl6, opt, &final);
1430 if (final_p)
1431 connected = false;
1432
1433 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr)) {
1434 fl6.flowi6_oif = np->mcast_oif;
1435 connected = false;
1436 } else if (!fl6.flowi6_oif)
1437 fl6.flowi6_oif = np->ucast_oif;
1438
1439 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
1440
1441 if (ipc6.tclass < 0)
1442 ipc6.tclass = np->tclass;
1443
1444 fl6.flowlabel = ip6_make_flowinfo(ipc6.tclass, fl6.flowlabel);
1445
1446 dst = ip6_sk_dst_lookup_flow(sk, &fl6, final_p, connected);
1447 if (IS_ERR(dst)) {
1448 err = PTR_ERR(dst);
1449 dst = NULL;
1450 goto out;
1451 }
1452
1453 if (ipc6.hlimit < 0)
1454 ipc6.hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
1455
1456 if (msg->msg_flags&MSG_CONFIRM)
1457 goto do_confirm;
1458back_from_confirm:
1459
1460 /* Lockless fast path for the non-corking case */
1461 if (!corkreq) {
1462 struct inet_cork_full cork;
1463 struct sk_buff *skb;
1464
1465 skb = ip6_make_skb(sk, getfrag, msg, ulen,
1466 sizeof(struct udphdr), &ipc6,
1467 &fl6, (struct rt6_info *)dst,
1468 msg->msg_flags, &cork);
1469 err = PTR_ERR(skb);
1470 if (!IS_ERR_OR_NULL(skb))
1471 err = udp_v6_send_skb(skb, &fl6, &cork.base);
1472 goto out;
1473 }
1474
1475 lock_sock(sk);
1476 if (unlikely(up->pending)) {
1477 /* The socket is already corked while preparing it. */
1478 /* ... which is an evident application bug. --ANK */
1479 release_sock(sk);
1480
1481 net_dbg_ratelimited("udp cork app bug 2\n");
1482 err = -EINVAL;
1483 goto out;
1484 }
1485
1486 up->pending = AF_INET6;
1487
1488do_append_data:
1489 if (ipc6.dontfrag < 0)
1490 ipc6.dontfrag = np->dontfrag;
1491 up->len += ulen;
1492 err = ip6_append_data(sk, getfrag, msg, ulen, sizeof(struct udphdr),
1493 &ipc6, &fl6, (struct rt6_info *)dst,
1494 corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags);
1495 if (err)
1496 udp_v6_flush_pending_frames(sk);
1497 else if (!corkreq)
1498 err = udp_v6_push_pending_frames(sk);
1499 else if (unlikely(skb_queue_empty(&sk->sk_write_queue)))
1500 up->pending = 0;
1501
1502 if (err > 0)
1503 err = np->recverr ? net_xmit_errno(err) : 0;
1504 release_sock(sk);
1505
1506out:
1507 dst_release(dst);
1508out_no_dst:
1509 fl6_sock_release(flowlabel);
1510 txopt_put(opt_to_free);
1511 if (!err)
1512 return len;
1513 /*
1514 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space. Reporting
1515 * ENOBUFS might not be good (it's not tunable per se), but otherwise
1516 * we don't have a good statistic (IpOutDiscards but it can be too many
1517 * things). We could add another new stat but at least for now that
1518 * seems like overkill.
1519 */
1520 if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) {
1521 UDP6_INC_STATS(sock_net(sk),
1522 UDP_MIB_SNDBUFERRORS, is_udplite);
1523 }
1524 return err;
1525
1526do_confirm:
1527 if (msg->msg_flags & MSG_PROBE)
1528 dst_confirm_neigh(dst, &fl6.daddr);
1529 if (!(msg->msg_flags&MSG_PROBE) || len)
1530 goto back_from_confirm;
1531 err = 0;
1532 goto out;
1533}
1534
1535void udpv6_destroy_sock(struct sock *sk)
1536{
1537 struct udp_sock *up = udp_sk(sk);
1538 lock_sock(sk);
1539 udp_v6_flush_pending_frames(sk);
1540 release_sock(sk);
1541
1542 if (static_branch_unlikely(&udpv6_encap_needed_key)) {
1543 if (up->encap_type) {
1544 void (*encap_destroy)(struct sock *sk);
1545 encap_destroy = READ_ONCE(up->encap_destroy);
1546 if (encap_destroy)
1547 encap_destroy(sk);
1548 }
1549 if (up->encap_enabled)
1550 static_branch_dec(&udpv6_encap_needed_key);
1551 }
1552
1553 inet6_destroy_sock(sk);
1554}
1555
1556/*
1557 * Socket option code for UDP
1558 */
1559int udpv6_setsockopt(struct sock *sk, int level, int optname,
1560 char __user *optval, unsigned int optlen)
1561{
1562 if (level == SOL_UDP || level == SOL_UDPLITE)
1563 return udp_lib_setsockopt(sk, level, optname, optval, optlen,
1564 udp_v6_push_pending_frames);
1565 return ipv6_setsockopt(sk, level, optname, optval, optlen);
1566}
1567
1568#ifdef CONFIG_COMPAT
1569int compat_udpv6_setsockopt(struct sock *sk, int level, int optname,
1570 char __user *optval, unsigned int optlen)
1571{
1572 if (level == SOL_UDP || level == SOL_UDPLITE)
1573 return udp_lib_setsockopt(sk, level, optname, optval, optlen,
1574 udp_v6_push_pending_frames);
1575 return compat_ipv6_setsockopt(sk, level, optname, optval, optlen);
1576}
1577#endif
1578
1579int udpv6_getsockopt(struct sock *sk, int level, int optname,
1580 char __user *optval, int __user *optlen)
1581{
1582 if (level == SOL_UDP || level == SOL_UDPLITE)
1583 return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1584 return ipv6_getsockopt(sk, level, optname, optval, optlen);
1585}
1586
1587#ifdef CONFIG_COMPAT
1588int compat_udpv6_getsockopt(struct sock *sk, int level, int optname,
1589 char __user *optval, int __user *optlen)
1590{
1591 if (level == SOL_UDP || level == SOL_UDPLITE)
1592 return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1593 return compat_ipv6_getsockopt(sk, level, optname, optval, optlen);
1594}
1595#endif
1596
1597/* thinking of making this const? Don't.
1598 * early_demux can change based on sysctl.
1599 */
1600static struct inet6_protocol udpv6_protocol = {
1601 .early_demux = udp_v6_early_demux,
1602 .early_demux_handler = udp_v6_early_demux,
1603 .handler = udpv6_rcv,
1604 .err_handler = udpv6_err,
1605 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1606};
1607
1608/* ------------------------------------------------------------------------ */
1609#ifdef CONFIG_PROC_FS
1610int udp6_seq_show(struct seq_file *seq, void *v)
1611{
1612 if (v == SEQ_START_TOKEN) {
1613 seq_puts(seq, IPV6_SEQ_DGRAM_HEADER);
1614 } else {
1615 int bucket = ((struct udp_iter_state *)seq->private)->bucket;
1616 struct inet_sock *inet = inet_sk(v);
1617 __u16 srcp = ntohs(inet->inet_sport);
1618 __u16 destp = ntohs(inet->inet_dport);
1619 __ip6_dgram_sock_seq_show(seq, v, srcp, destp,
1620 udp_rqueue_get(v), bucket);
1621 }
1622 return 0;
1623}
1624
1625const struct seq_operations udp6_seq_ops = {
1626 .start = udp_seq_start,
1627 .next = udp_seq_next,
1628 .stop = udp_seq_stop,
1629 .show = udp6_seq_show,
1630};
1631EXPORT_SYMBOL(udp6_seq_ops);
1632
1633static struct udp_seq_afinfo udp6_seq_afinfo = {
1634 .family = AF_INET6,
1635 .udp_table = &udp_table,
1636};
1637
1638int __net_init udp6_proc_init(struct net *net)
1639{
1640 if (!proc_create_net_data("udp6", 0444, net->proc_net, &udp6_seq_ops,
1641 sizeof(struct udp_iter_state), &udp6_seq_afinfo))
1642 return -ENOMEM;
1643 return 0;
1644}
1645
1646void udp6_proc_exit(struct net *net)
1647{
1648 remove_proc_entry("udp6", net->proc_net);
1649}
1650#endif /* CONFIG_PROC_FS */
1651
1652/* ------------------------------------------------------------------------ */
1653
1654struct proto udpv6_prot = {
1655 .name = "UDPv6",
1656 .owner = THIS_MODULE,
1657 .close = udp_lib_close,
1658 .pre_connect = udpv6_pre_connect,
1659 .connect = ip6_datagram_connect,
1660 .disconnect = udp_disconnect,
1661 .ioctl = udp_ioctl,
1662 .init = udp_init_sock,
1663 .destroy = udpv6_destroy_sock,
1664 .setsockopt = udpv6_setsockopt,
1665 .getsockopt = udpv6_getsockopt,
1666 .sendmsg = udpv6_sendmsg,
1667 .recvmsg = udpv6_recvmsg,
1668 .release_cb = ip6_datagram_release_cb,
1669 .hash = udp_lib_hash,
1670 .unhash = udp_lib_unhash,
1671 .rehash = udp_v6_rehash,
1672 .get_port = udp_v6_get_port,
1673 .memory_allocated = &udp_memory_allocated,
1674 .sysctl_mem = sysctl_udp_mem,
1675 .sysctl_wmem_offset = offsetof(struct net, ipv4.sysctl_udp_wmem_min),
1676 .sysctl_rmem_offset = offsetof(struct net, ipv4.sysctl_udp_rmem_min),
1677 .obj_size = sizeof(struct udp6_sock),
1678 .h.udp_table = &udp_table,
1679#ifdef CONFIG_COMPAT
1680 .compat_setsockopt = compat_udpv6_setsockopt,
1681 .compat_getsockopt = compat_udpv6_getsockopt,
1682#endif
1683 .diag_destroy = udp_abort,
1684};
1685
1686static struct inet_protosw udpv6_protosw = {
1687 .type = SOCK_DGRAM,
1688 .protocol = IPPROTO_UDP,
1689 .prot = &udpv6_prot,
1690 .ops = &inet6_dgram_ops,
1691 .flags = INET_PROTOSW_PERMANENT,
1692};
1693
1694int __init udpv6_init(void)
1695{
1696 int ret;
1697
1698 ret = inet6_add_protocol(&udpv6_protocol, IPPROTO_UDP);
1699 if (ret)
1700 goto out;
1701
1702 ret = inet6_register_protosw(&udpv6_protosw);
1703 if (ret)
1704 goto out_udpv6_protocol;
1705out:
1706 return ret;
1707
1708out_udpv6_protocol:
1709 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1710 goto out;
1711}
1712
1713void udpv6_exit(void)
1714{
1715 inet6_unregister_protosw(&udpv6_protosw);
1716 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1717}