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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/bpf-cgroup.h>
21#include <linux/errno.h>
22#include <linux/types.h>
23#include <linux/socket.h>
24#include <linux/sockios.h>
25#include <linux/net.h>
26#include <linux/in6.h>
27#include <linux/netdevice.h>
28#include <linux/if_arp.h>
29#include <linux/ipv6.h>
30#include <linux/icmpv6.h>
31#include <linux/init.h>
32#include <linux/module.h>
33#include <linux/skbuff.h>
34#include <linux/slab.h>
35#include <linux/uaccess.h>
36#include <linux/indirect_call_wrapper.h>
37
38#include <net/addrconf.h>
39#include <net/ndisc.h>
40#include <net/protocol.h>
41#include <net/transp_v6.h>
42#include <net/ip6_route.h>
43#include <net/raw.h>
44#include <net/seg6.h>
45#include <net/tcp_states.h>
46#include <net/ip6_checksum.h>
47#include <net/ip6_tunnel.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 void udpv6_destruct_sock(struct sock *sk)
60{
61 udp_destruct_common(sk);
62 inet6_sock_destruct(sk);
63}
64
65int udpv6_init_sock(struct sock *sk)
66{
67 udp_lib_init_sock(sk);
68 sk->sk_destruct = udpv6_destruct_sock;
69 set_bit(SOCK_SUPPORT_ZC, &sk->sk_socket->flags);
70 return 0;
71}
72
73static u32 udp6_ehashfn(const struct net *net,
74 const struct in6_addr *laddr,
75 const u16 lport,
76 const struct in6_addr *faddr,
77 const __be16 fport)
78{
79 static u32 udp6_ehash_secret __read_mostly;
80 static u32 udp_ipv6_hash_secret __read_mostly;
81
82 u32 lhash, fhash;
83
84 net_get_random_once(&udp6_ehash_secret,
85 sizeof(udp6_ehash_secret));
86 net_get_random_once(&udp_ipv6_hash_secret,
87 sizeof(udp_ipv6_hash_secret));
88
89 lhash = (__force u32)laddr->s6_addr32[3];
90 fhash = __ipv6_addr_jhash(faddr, udp_ipv6_hash_secret);
91
92 return __inet6_ehashfn(lhash, lport, fhash, fport,
93 udp_ipv6_hash_secret + net_hash_mix(net));
94}
95
96int udp_v6_get_port(struct sock *sk, unsigned short snum)
97{
98 unsigned int hash2_nulladdr =
99 ipv6_portaddr_hash(sock_net(sk), &in6addr_any, snum);
100 unsigned int hash2_partial =
101 ipv6_portaddr_hash(sock_net(sk), &sk->sk_v6_rcv_saddr, 0);
102
103 /* precompute partial secondary hash */
104 udp_sk(sk)->udp_portaddr_hash = hash2_partial;
105 return udp_lib_get_port(sk, snum, hash2_nulladdr);
106}
107
108void udp_v6_rehash(struct sock *sk)
109{
110 u16 new_hash = ipv6_portaddr_hash(sock_net(sk),
111 &sk->sk_v6_rcv_saddr,
112 inet_sk(sk)->inet_num);
113
114 udp_lib_rehash(sk, new_hash);
115}
116
117static int compute_score(struct sock *sk, struct net *net,
118 const struct in6_addr *saddr, __be16 sport,
119 const struct in6_addr *daddr, unsigned short hnum,
120 int dif, int sdif)
121{
122 int bound_dev_if, score;
123 struct inet_sock *inet;
124 bool dev_match;
125
126 if (!net_eq(sock_net(sk), net) ||
127 udp_sk(sk)->udp_port_hash != hnum ||
128 sk->sk_family != PF_INET6)
129 return -1;
130
131 if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
132 return -1;
133
134 score = 0;
135 inet = inet_sk(sk);
136
137 if (inet->inet_dport) {
138 if (inet->inet_dport != sport)
139 return -1;
140 score++;
141 }
142
143 if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
144 if (!ipv6_addr_equal(&sk->sk_v6_daddr, saddr))
145 return -1;
146 score++;
147 }
148
149 bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
150 dev_match = udp_sk_bound_dev_eq(net, bound_dev_if, dif, sdif);
151 if (!dev_match)
152 return -1;
153 if (bound_dev_if)
154 score++;
155
156 if (READ_ONCE(sk->sk_incoming_cpu) == raw_smp_processor_id())
157 score++;
158
159 return score;
160}
161
162static struct sock *lookup_reuseport(struct net *net, struct sock *sk,
163 struct sk_buff *skb,
164 const struct in6_addr *saddr,
165 __be16 sport,
166 const struct in6_addr *daddr,
167 unsigned int hnum)
168{
169 struct sock *reuse_sk = NULL;
170 u32 hash;
171
172 if (sk->sk_reuseport && sk->sk_state != TCP_ESTABLISHED) {
173 hash = udp6_ehashfn(net, daddr, hnum, saddr, sport);
174 reuse_sk = reuseport_select_sock(sk, hash, skb,
175 sizeof(struct udphdr));
176 }
177 return reuse_sk;
178}
179
180/* called with rcu_read_lock() */
181static struct sock *udp6_lib_lookup2(struct net *net,
182 const struct in6_addr *saddr, __be16 sport,
183 const struct in6_addr *daddr, unsigned int hnum,
184 int dif, int sdif, struct udp_hslot *hslot2,
185 struct sk_buff *skb)
186{
187 struct sock *sk, *result;
188 int score, badness;
189
190 result = NULL;
191 badness = -1;
192 udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) {
193 score = compute_score(sk, net, saddr, sport,
194 daddr, hnum, dif, sdif);
195 if (score > badness) {
196 result = lookup_reuseport(net, sk, skb,
197 saddr, sport, daddr, hnum);
198 /* Fall back to scoring if group has connections */
199 if (result && !reuseport_has_conns(sk))
200 return result;
201
202 result = result ? : sk;
203 badness = score;
204 }
205 }
206 return result;
207}
208
209static inline struct sock *udp6_lookup_run_bpf(struct net *net,
210 struct udp_table *udptable,
211 struct sk_buff *skb,
212 const struct in6_addr *saddr,
213 __be16 sport,
214 const struct in6_addr *daddr,
215 u16 hnum, const int dif)
216{
217 struct sock *sk, *reuse_sk;
218 bool no_reuseport;
219
220 if (udptable != net->ipv4.udp_table)
221 return NULL; /* only UDP is supported */
222
223 no_reuseport = bpf_sk_lookup_run_v6(net, IPPROTO_UDP, saddr, sport,
224 daddr, hnum, dif, &sk);
225 if (no_reuseport || IS_ERR_OR_NULL(sk))
226 return sk;
227
228 reuse_sk = lookup_reuseport(net, sk, skb, saddr, sport, daddr, hnum);
229 if (reuse_sk)
230 sk = reuse_sk;
231 return sk;
232}
233
234/* rcu_read_lock() must be held */
235struct sock *__udp6_lib_lookup(struct net *net,
236 const struct in6_addr *saddr, __be16 sport,
237 const struct in6_addr *daddr, __be16 dport,
238 int dif, int sdif, struct udp_table *udptable,
239 struct sk_buff *skb)
240{
241 unsigned short hnum = ntohs(dport);
242 unsigned int hash2, slot2;
243 struct udp_hslot *hslot2;
244 struct sock *result, *sk;
245
246 hash2 = ipv6_portaddr_hash(net, daddr, hnum);
247 slot2 = hash2 & udptable->mask;
248 hslot2 = &udptable->hash2[slot2];
249
250 /* Lookup connected or non-wildcard sockets */
251 result = udp6_lib_lookup2(net, saddr, sport,
252 daddr, hnum, dif, sdif,
253 hslot2, skb);
254 if (!IS_ERR_OR_NULL(result) && result->sk_state == TCP_ESTABLISHED)
255 goto done;
256
257 /* Lookup redirect from BPF */
258 if (static_branch_unlikely(&bpf_sk_lookup_enabled)) {
259 sk = udp6_lookup_run_bpf(net, udptable, skb,
260 saddr, sport, daddr, hnum, dif);
261 if (sk) {
262 result = sk;
263 goto done;
264 }
265 }
266
267 /* Got non-wildcard socket or error on first lookup */
268 if (result)
269 goto done;
270
271 /* Lookup wildcard sockets */
272 hash2 = ipv6_portaddr_hash(net, &in6addr_any, hnum);
273 slot2 = hash2 & udptable->mask;
274 hslot2 = &udptable->hash2[slot2];
275
276 result = udp6_lib_lookup2(net, saddr, sport,
277 &in6addr_any, hnum, dif, sdif,
278 hslot2, skb);
279done:
280 if (IS_ERR(result))
281 return NULL;
282 return result;
283}
284EXPORT_SYMBOL_GPL(__udp6_lib_lookup);
285
286static struct sock *__udp6_lib_lookup_skb(struct sk_buff *skb,
287 __be16 sport, __be16 dport,
288 struct udp_table *udptable)
289{
290 const struct ipv6hdr *iph = ipv6_hdr(skb);
291
292 return __udp6_lib_lookup(dev_net(skb->dev), &iph->saddr, sport,
293 &iph->daddr, dport, inet6_iif(skb),
294 inet6_sdif(skb), udptable, skb);
295}
296
297struct sock *udp6_lib_lookup_skb(const struct sk_buff *skb,
298 __be16 sport, __be16 dport)
299{
300 const struct ipv6hdr *iph = ipv6_hdr(skb);
301 struct net *net = dev_net(skb->dev);
302
303 return __udp6_lib_lookup(net, &iph->saddr, sport,
304 &iph->daddr, dport, inet6_iif(skb),
305 inet6_sdif(skb), net->ipv4.udp_table, NULL);
306}
307
308/* Must be called under rcu_read_lock().
309 * Does increment socket refcount.
310 */
311#if IS_ENABLED(CONFIG_NF_TPROXY_IPV6) || IS_ENABLED(CONFIG_NF_SOCKET_IPV6)
312struct sock *udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport,
313 const struct in6_addr *daddr, __be16 dport, int dif)
314{
315 struct sock *sk;
316
317 sk = __udp6_lib_lookup(net, saddr, sport, daddr, dport,
318 dif, 0, net->ipv4.udp_table, NULL);
319 if (sk && !refcount_inc_not_zero(&sk->sk_refcnt))
320 sk = NULL;
321 return sk;
322}
323EXPORT_SYMBOL_GPL(udp6_lib_lookup);
324#endif
325
326/* do not use the scratch area len for jumbogram: their length execeeds the
327 * scratch area space; note that the IP6CB flags is still in the first
328 * cacheline, so checking for jumbograms is cheap
329 */
330static int udp6_skb_len(struct sk_buff *skb)
331{
332 return unlikely(inet6_is_jumbogram(skb)) ? skb->len : udp_skb_len(skb);
333}
334
335/*
336 * This should be easy, if there is something there we
337 * return it, otherwise we block.
338 */
339
340int udpv6_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
341 int flags, int *addr_len)
342{
343 struct ipv6_pinfo *np = inet6_sk(sk);
344 struct inet_sock *inet = inet_sk(sk);
345 struct sk_buff *skb;
346 unsigned int ulen, copied;
347 int off, err, peeking = flags & MSG_PEEK;
348 int is_udplite = IS_UDPLITE(sk);
349 struct udp_mib __percpu *mib;
350 bool checksum_valid = false;
351 int is_udp4;
352
353 if (flags & MSG_ERRQUEUE)
354 return ipv6_recv_error(sk, msg, len, addr_len);
355
356 if (np->rxpmtu && np->rxopt.bits.rxpmtu)
357 return ipv6_recv_rxpmtu(sk, msg, len, addr_len);
358
359try_again:
360 off = sk_peek_offset(sk, flags);
361 skb = __skb_recv_udp(sk, flags, &off, &err);
362 if (!skb)
363 return err;
364
365 ulen = udp6_skb_len(skb);
366 copied = len;
367 if (copied > ulen - off)
368 copied = ulen - off;
369 else if (copied < ulen)
370 msg->msg_flags |= MSG_TRUNC;
371
372 is_udp4 = (skb->protocol == htons(ETH_P_IP));
373 mib = __UDPX_MIB(sk, is_udp4);
374
375 /*
376 * If checksum is needed at all, try to do it while copying the
377 * data. If the data is truncated, or if we only want a partial
378 * coverage checksum (UDP-Lite), do it before the copy.
379 */
380
381 if (copied < ulen || peeking ||
382 (is_udplite && UDP_SKB_CB(skb)->partial_cov)) {
383 checksum_valid = udp_skb_csum_unnecessary(skb) ||
384 !__udp_lib_checksum_complete(skb);
385 if (!checksum_valid)
386 goto csum_copy_err;
387 }
388
389 if (checksum_valid || udp_skb_csum_unnecessary(skb)) {
390 if (udp_skb_is_linear(skb))
391 err = copy_linear_skb(skb, copied, off, &msg->msg_iter);
392 else
393 err = skb_copy_datagram_msg(skb, off, msg, copied);
394 } else {
395 err = skb_copy_and_csum_datagram_msg(skb, off, msg);
396 if (err == -EINVAL)
397 goto csum_copy_err;
398 }
399 if (unlikely(err)) {
400 if (!peeking) {
401 atomic_inc(&sk->sk_drops);
402 SNMP_INC_STATS(mib, UDP_MIB_INERRORS);
403 }
404 kfree_skb(skb);
405 return err;
406 }
407 if (!peeking)
408 SNMP_INC_STATS(mib, UDP_MIB_INDATAGRAMS);
409
410 sock_recv_cmsgs(msg, sk, skb);
411
412 /* Copy the address. */
413 if (msg->msg_name) {
414 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
415 sin6->sin6_family = AF_INET6;
416 sin6->sin6_port = udp_hdr(skb)->source;
417 sin6->sin6_flowinfo = 0;
418
419 if (is_udp4) {
420 ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
421 &sin6->sin6_addr);
422 sin6->sin6_scope_id = 0;
423 } else {
424 sin6->sin6_addr = ipv6_hdr(skb)->saddr;
425 sin6->sin6_scope_id =
426 ipv6_iface_scope_id(&sin6->sin6_addr,
427 inet6_iif(skb));
428 }
429 *addr_len = sizeof(*sin6);
430
431 BPF_CGROUP_RUN_PROG_UDP6_RECVMSG_LOCK(sk,
432 (struct sockaddr *)sin6);
433 }
434
435 if (udp_sk(sk)->gro_enabled)
436 udp_cmsg_recv(msg, sk, skb);
437
438 if (np->rxopt.all)
439 ip6_datagram_recv_common_ctl(sk, msg, skb);
440
441 if (is_udp4) {
442 if (inet->cmsg_flags)
443 ip_cmsg_recv_offset(msg, sk, skb,
444 sizeof(struct udphdr), off);
445 } else {
446 if (np->rxopt.all)
447 ip6_datagram_recv_specific_ctl(sk, msg, skb);
448 }
449
450 err = copied;
451 if (flags & MSG_TRUNC)
452 err = ulen;
453
454 skb_consume_udp(sk, skb, peeking ? -err : err);
455 return err;
456
457csum_copy_err:
458 if (!__sk_queue_drop_skb(sk, &udp_sk(sk)->reader_queue, skb, flags,
459 udp_skb_destructor)) {
460 SNMP_INC_STATS(mib, UDP_MIB_CSUMERRORS);
461 SNMP_INC_STATS(mib, UDP_MIB_INERRORS);
462 }
463 kfree_skb(skb);
464
465 /* starting over for a new packet, but check if we need to yield */
466 cond_resched();
467 msg->msg_flags &= ~MSG_TRUNC;
468 goto try_again;
469}
470
471DEFINE_STATIC_KEY_FALSE(udpv6_encap_needed_key);
472void udpv6_encap_enable(void)
473{
474 static_branch_inc(&udpv6_encap_needed_key);
475}
476EXPORT_SYMBOL(udpv6_encap_enable);
477
478/* Handler for tunnels with arbitrary destination ports: no socket lookup, go
479 * through error handlers in encapsulations looking for a match.
480 */
481static int __udp6_lib_err_encap_no_sk(struct sk_buff *skb,
482 struct inet6_skb_parm *opt,
483 u8 type, u8 code, int offset, __be32 info)
484{
485 int i;
486
487 for (i = 0; i < MAX_IPTUN_ENCAP_OPS; i++) {
488 int (*handler)(struct sk_buff *skb, struct inet6_skb_parm *opt,
489 u8 type, u8 code, int offset, __be32 info);
490 const struct ip6_tnl_encap_ops *encap;
491
492 encap = rcu_dereference(ip6tun_encaps[i]);
493 if (!encap)
494 continue;
495 handler = encap->err_handler;
496 if (handler && !handler(skb, opt, type, code, offset, info))
497 return 0;
498 }
499
500 return -ENOENT;
501}
502
503/* Try to match ICMP errors to UDP tunnels by looking up a socket without
504 * reversing source and destination port: this will match tunnels that force the
505 * same destination port on both endpoints (e.g. VXLAN, GENEVE). Note that
506 * lwtunnels might actually break this assumption by being configured with
507 * different destination ports on endpoints, in this case we won't be able to
508 * trace ICMP messages back to them.
509 *
510 * If this doesn't match any socket, probe tunnels with arbitrary destination
511 * ports (e.g. FoU, GUE): there, the receiving socket is useless, as the port
512 * we've sent packets to won't necessarily match the local destination port.
513 *
514 * Then ask the tunnel implementation to match the error against a valid
515 * association.
516 *
517 * Return an error if we can't find a match, the socket if we need further
518 * processing, zero otherwise.
519 */
520static struct sock *__udp6_lib_err_encap(struct net *net,
521 const struct ipv6hdr *hdr, int offset,
522 struct udphdr *uh,
523 struct udp_table *udptable,
524 struct sock *sk,
525 struct sk_buff *skb,
526 struct inet6_skb_parm *opt,
527 u8 type, u8 code, __be32 info)
528{
529 int (*lookup)(struct sock *sk, struct sk_buff *skb);
530 int network_offset, transport_offset;
531 struct udp_sock *up;
532
533 network_offset = skb_network_offset(skb);
534 transport_offset = skb_transport_offset(skb);
535
536 /* Network header needs to point to the outer IPv6 header inside ICMP */
537 skb_reset_network_header(skb);
538
539 /* Transport header needs to point to the UDP header */
540 skb_set_transport_header(skb, offset);
541
542 if (sk) {
543 up = udp_sk(sk);
544
545 lookup = READ_ONCE(up->encap_err_lookup);
546 if (lookup && lookup(sk, skb))
547 sk = NULL;
548
549 goto out;
550 }
551
552 sk = __udp6_lib_lookup(net, &hdr->daddr, uh->source,
553 &hdr->saddr, uh->dest,
554 inet6_iif(skb), 0, udptable, skb);
555 if (sk) {
556 up = udp_sk(sk);
557
558 lookup = READ_ONCE(up->encap_err_lookup);
559 if (!lookup || lookup(sk, skb))
560 sk = NULL;
561 }
562
563out:
564 if (!sk) {
565 sk = ERR_PTR(__udp6_lib_err_encap_no_sk(skb, opt, type, code,
566 offset, info));
567 }
568
569 skb_set_transport_header(skb, transport_offset);
570 skb_set_network_header(skb, network_offset);
571
572 return sk;
573}
574
575int __udp6_lib_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
576 u8 type, u8 code, int offset, __be32 info,
577 struct udp_table *udptable)
578{
579 struct ipv6_pinfo *np;
580 const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data;
581 const struct in6_addr *saddr = &hdr->saddr;
582 const struct in6_addr *daddr = seg6_get_daddr(skb, opt) ? : &hdr->daddr;
583 struct udphdr *uh = (struct udphdr *)(skb->data+offset);
584 bool tunnel = false;
585 struct sock *sk;
586 int harderr;
587 int err;
588 struct net *net = dev_net(skb->dev);
589
590 sk = __udp6_lib_lookup(net, daddr, uh->dest, saddr, uh->source,
591 inet6_iif(skb), inet6_sdif(skb), udptable, NULL);
592
593 if (!sk || udp_sk(sk)->encap_type) {
594 /* No socket for error: try tunnels before discarding */
595 if (static_branch_unlikely(&udpv6_encap_needed_key)) {
596 sk = __udp6_lib_err_encap(net, hdr, offset, uh,
597 udptable, sk, skb,
598 opt, type, code, info);
599 if (!sk)
600 return 0;
601 } else
602 sk = ERR_PTR(-ENOENT);
603
604 if (IS_ERR(sk)) {
605 __ICMP6_INC_STATS(net, __in6_dev_get(skb->dev),
606 ICMP6_MIB_INERRORS);
607 return PTR_ERR(sk);
608 }
609
610 tunnel = true;
611 }
612
613 harderr = icmpv6_err_convert(type, code, &err);
614 np = inet6_sk(sk);
615
616 if (type == ICMPV6_PKT_TOOBIG) {
617 if (!ip6_sk_accept_pmtu(sk))
618 goto out;
619 ip6_sk_update_pmtu(skb, sk, info);
620 if (np->pmtudisc != IPV6_PMTUDISC_DONT)
621 harderr = 1;
622 }
623 if (type == NDISC_REDIRECT) {
624 if (tunnel) {
625 ip6_redirect(skb, sock_net(sk), inet6_iif(skb),
626 sk->sk_mark, sk->sk_uid);
627 } else {
628 ip6_sk_redirect(skb, sk);
629 }
630 goto out;
631 }
632
633 /* Tunnels don't have an application socket: don't pass errors back */
634 if (tunnel) {
635 if (udp_sk(sk)->encap_err_rcv)
636 udp_sk(sk)->encap_err_rcv(sk, skb, err, uh->dest,
637 ntohl(info), (u8 *)(uh+1));
638 goto out;
639 }
640
641 if (!np->recverr) {
642 if (!harderr || sk->sk_state != TCP_ESTABLISHED)
643 goto out;
644 } else {
645 ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1));
646 }
647
648 sk->sk_err = err;
649 sk_error_report(sk);
650out:
651 return 0;
652}
653
654static int __udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
655{
656 int rc;
657
658 if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
659 sock_rps_save_rxhash(sk, skb);
660 sk_mark_napi_id(sk, skb);
661 sk_incoming_cpu_update(sk);
662 } else {
663 sk_mark_napi_id_once(sk, skb);
664 }
665
666 rc = __udp_enqueue_schedule_skb(sk, skb);
667 if (rc < 0) {
668 int is_udplite = IS_UDPLITE(sk);
669 enum skb_drop_reason drop_reason;
670
671 /* Note that an ENOMEM error is charged twice */
672 if (rc == -ENOMEM) {
673 UDP6_INC_STATS(sock_net(sk),
674 UDP_MIB_RCVBUFERRORS, is_udplite);
675 drop_reason = SKB_DROP_REASON_SOCKET_RCVBUFF;
676 } else {
677 UDP6_INC_STATS(sock_net(sk),
678 UDP_MIB_MEMERRORS, is_udplite);
679 drop_reason = SKB_DROP_REASON_PROTO_MEM;
680 }
681 UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
682 kfree_skb_reason(skb, drop_reason);
683 return -1;
684 }
685
686 return 0;
687}
688
689static __inline__ int udpv6_err(struct sk_buff *skb,
690 struct inet6_skb_parm *opt, u8 type,
691 u8 code, int offset, __be32 info)
692{
693 return __udp6_lib_err(skb, opt, type, code, offset, info,
694 dev_net(skb->dev)->ipv4.udp_table);
695}
696
697static int udpv6_queue_rcv_one_skb(struct sock *sk, struct sk_buff *skb)
698{
699 enum skb_drop_reason drop_reason = SKB_DROP_REASON_NOT_SPECIFIED;
700 struct udp_sock *up = udp_sk(sk);
701 int is_udplite = IS_UDPLITE(sk);
702
703 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) {
704 drop_reason = SKB_DROP_REASON_XFRM_POLICY;
705 goto drop;
706 }
707
708 if (static_branch_unlikely(&udpv6_encap_needed_key) && up->encap_type) {
709 int (*encap_rcv)(struct sock *sk, struct sk_buff *skb);
710
711 /*
712 * This is an encapsulation socket so pass the skb to
713 * the socket's udp_encap_rcv() hook. Otherwise, just
714 * fall through and pass this up the UDP socket.
715 * up->encap_rcv() returns the following value:
716 * =0 if skb was successfully passed to the encap
717 * handler or was discarded by it.
718 * >0 if skb should be passed on to UDP.
719 * <0 if skb should be resubmitted as proto -N
720 */
721
722 /* if we're overly short, let UDP handle it */
723 encap_rcv = READ_ONCE(up->encap_rcv);
724 if (encap_rcv) {
725 int ret;
726
727 /* Verify checksum before giving to encap */
728 if (udp_lib_checksum_complete(skb))
729 goto csum_error;
730
731 ret = encap_rcv(sk, skb);
732 if (ret <= 0) {
733 __UDP6_INC_STATS(sock_net(sk),
734 UDP_MIB_INDATAGRAMS,
735 is_udplite);
736 return -ret;
737 }
738 }
739
740 /* FALLTHROUGH -- it's a UDP Packet */
741 }
742
743 /*
744 * UDP-Lite specific tests, ignored on UDP sockets (see net/ipv4/udp.c).
745 */
746 if ((up->pcflag & UDPLITE_RECV_CC) && UDP_SKB_CB(skb)->partial_cov) {
747
748 if (up->pcrlen == 0) { /* full coverage was set */
749 net_dbg_ratelimited("UDPLITE6: partial coverage %d while full coverage %d requested\n",
750 UDP_SKB_CB(skb)->cscov, skb->len);
751 goto drop;
752 }
753 if (UDP_SKB_CB(skb)->cscov < up->pcrlen) {
754 net_dbg_ratelimited("UDPLITE6: coverage %d too small, need min %d\n",
755 UDP_SKB_CB(skb)->cscov, up->pcrlen);
756 goto drop;
757 }
758 }
759
760 prefetch(&sk->sk_rmem_alloc);
761 if (rcu_access_pointer(sk->sk_filter) &&
762 udp_lib_checksum_complete(skb))
763 goto csum_error;
764
765 if (sk_filter_trim_cap(sk, skb, sizeof(struct udphdr))) {
766 drop_reason = SKB_DROP_REASON_SOCKET_FILTER;
767 goto drop;
768 }
769
770 udp_csum_pull_header(skb);
771
772 skb_dst_drop(skb);
773
774 return __udpv6_queue_rcv_skb(sk, skb);
775
776csum_error:
777 drop_reason = SKB_DROP_REASON_UDP_CSUM;
778 __UDP6_INC_STATS(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite);
779drop:
780 __UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
781 atomic_inc(&sk->sk_drops);
782 kfree_skb_reason(skb, drop_reason);
783 return -1;
784}
785
786static int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
787{
788 struct sk_buff *next, *segs;
789 int ret;
790
791 if (likely(!udp_unexpected_gso(sk, skb)))
792 return udpv6_queue_rcv_one_skb(sk, skb);
793
794 __skb_push(skb, -skb_mac_offset(skb));
795 segs = udp_rcv_segment(sk, skb, false);
796 skb_list_walk_safe(segs, skb, next) {
797 __skb_pull(skb, skb_transport_offset(skb));
798
799 udp_post_segment_fix_csum(skb);
800 ret = udpv6_queue_rcv_one_skb(sk, skb);
801 if (ret > 0)
802 ip6_protocol_deliver_rcu(dev_net(skb->dev), skb, ret,
803 true);
804 }
805 return 0;
806}
807
808static bool __udp_v6_is_mcast_sock(struct net *net, struct sock *sk,
809 __be16 loc_port, const struct in6_addr *loc_addr,
810 __be16 rmt_port, const struct in6_addr *rmt_addr,
811 int dif, int sdif, unsigned short hnum)
812{
813 struct inet_sock *inet = inet_sk(sk);
814
815 if (!net_eq(sock_net(sk), net))
816 return false;
817
818 if (udp_sk(sk)->udp_port_hash != hnum ||
819 sk->sk_family != PF_INET6 ||
820 (inet->inet_dport && inet->inet_dport != rmt_port) ||
821 (!ipv6_addr_any(&sk->sk_v6_daddr) &&
822 !ipv6_addr_equal(&sk->sk_v6_daddr, rmt_addr)) ||
823 !udp_sk_bound_dev_eq(net, READ_ONCE(sk->sk_bound_dev_if), dif, sdif) ||
824 (!ipv6_addr_any(&sk->sk_v6_rcv_saddr) &&
825 !ipv6_addr_equal(&sk->sk_v6_rcv_saddr, loc_addr)))
826 return false;
827 if (!inet6_mc_check(sk, loc_addr, rmt_addr))
828 return false;
829 return true;
830}
831
832static void udp6_csum_zero_error(struct sk_buff *skb)
833{
834 /* RFC 2460 section 8.1 says that we SHOULD log
835 * this error. Well, it is reasonable.
836 */
837 net_dbg_ratelimited("IPv6: udp checksum is 0 for [%pI6c]:%u->[%pI6c]:%u\n",
838 &ipv6_hdr(skb)->saddr, ntohs(udp_hdr(skb)->source),
839 &ipv6_hdr(skb)->daddr, ntohs(udp_hdr(skb)->dest));
840}
841
842/*
843 * Note: called only from the BH handler context,
844 * so we don't need to lock the hashes.
845 */
846static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
847 const struct in6_addr *saddr, const struct in6_addr *daddr,
848 struct udp_table *udptable, int proto)
849{
850 struct sock *sk, *first = NULL;
851 const struct udphdr *uh = udp_hdr(skb);
852 unsigned short hnum = ntohs(uh->dest);
853 struct udp_hslot *hslot = udp_hashslot(udptable, net, hnum);
854 unsigned int offset = offsetof(typeof(*sk), sk_node);
855 unsigned int hash2 = 0, hash2_any = 0, use_hash2 = (hslot->count > 10);
856 int dif = inet6_iif(skb);
857 int sdif = inet6_sdif(skb);
858 struct hlist_node *node;
859 struct sk_buff *nskb;
860
861 if (use_hash2) {
862 hash2_any = ipv6_portaddr_hash(net, &in6addr_any, hnum) &
863 udptable->mask;
864 hash2 = ipv6_portaddr_hash(net, daddr, hnum) & udptable->mask;
865start_lookup:
866 hslot = &udptable->hash2[hash2];
867 offset = offsetof(typeof(*sk), __sk_common.skc_portaddr_node);
868 }
869
870 sk_for_each_entry_offset_rcu(sk, node, &hslot->head, offset) {
871 if (!__udp_v6_is_mcast_sock(net, sk, uh->dest, daddr,
872 uh->source, saddr, dif, sdif,
873 hnum))
874 continue;
875 /* If zero checksum and no_check is not on for
876 * the socket then skip it.
877 */
878 if (!uh->check && !udp_sk(sk)->no_check6_rx)
879 continue;
880 if (!first) {
881 first = sk;
882 continue;
883 }
884 nskb = skb_clone(skb, GFP_ATOMIC);
885 if (unlikely(!nskb)) {
886 atomic_inc(&sk->sk_drops);
887 __UDP6_INC_STATS(net, UDP_MIB_RCVBUFERRORS,
888 IS_UDPLITE(sk));
889 __UDP6_INC_STATS(net, UDP_MIB_INERRORS,
890 IS_UDPLITE(sk));
891 continue;
892 }
893
894 if (udpv6_queue_rcv_skb(sk, nskb) > 0)
895 consume_skb(nskb);
896 }
897
898 /* Also lookup *:port if we are using hash2 and haven't done so yet. */
899 if (use_hash2 && hash2 != hash2_any) {
900 hash2 = hash2_any;
901 goto start_lookup;
902 }
903
904 if (first) {
905 if (udpv6_queue_rcv_skb(first, skb) > 0)
906 consume_skb(skb);
907 } else {
908 kfree_skb(skb);
909 __UDP6_INC_STATS(net, UDP_MIB_IGNOREDMULTI,
910 proto == IPPROTO_UDPLITE);
911 }
912 return 0;
913}
914
915static void udp6_sk_rx_dst_set(struct sock *sk, struct dst_entry *dst)
916{
917 if (udp_sk_rx_dst_set(sk, dst)) {
918 const struct rt6_info *rt = (const struct rt6_info *)dst;
919
920 sk->sk_rx_dst_cookie = rt6_get_cookie(rt);
921 }
922}
923
924/* wrapper for udp_queue_rcv_skb tacking care of csum conversion and
925 * return code conversion for ip layer consumption
926 */
927static int udp6_unicast_rcv_skb(struct sock *sk, struct sk_buff *skb,
928 struct udphdr *uh)
929{
930 int ret;
931
932 if (inet_get_convert_csum(sk) && uh->check && !IS_UDPLITE(sk))
933 skb_checksum_try_convert(skb, IPPROTO_UDP, ip6_compute_pseudo);
934
935 ret = udpv6_queue_rcv_skb(sk, skb);
936
937 /* a return value > 0 means to resubmit the input */
938 if (ret > 0)
939 return ret;
940 return 0;
941}
942
943int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
944 int proto)
945{
946 enum skb_drop_reason reason = SKB_DROP_REASON_NOT_SPECIFIED;
947 const struct in6_addr *saddr, *daddr;
948 struct net *net = dev_net(skb->dev);
949 struct udphdr *uh;
950 struct sock *sk;
951 bool refcounted;
952 u32 ulen = 0;
953
954 if (!pskb_may_pull(skb, sizeof(struct udphdr)))
955 goto discard;
956
957 saddr = &ipv6_hdr(skb)->saddr;
958 daddr = &ipv6_hdr(skb)->daddr;
959 uh = udp_hdr(skb);
960
961 ulen = ntohs(uh->len);
962 if (ulen > skb->len)
963 goto short_packet;
964
965 if (proto == IPPROTO_UDP) {
966 /* UDP validates ulen. */
967
968 /* Check for jumbo payload */
969 if (ulen == 0)
970 ulen = skb->len;
971
972 if (ulen < sizeof(*uh))
973 goto short_packet;
974
975 if (ulen < skb->len) {
976 if (pskb_trim_rcsum(skb, ulen))
977 goto short_packet;
978 saddr = &ipv6_hdr(skb)->saddr;
979 daddr = &ipv6_hdr(skb)->daddr;
980 uh = udp_hdr(skb);
981 }
982 }
983
984 if (udp6_csum_init(skb, uh, proto))
985 goto csum_error;
986
987 /* Check if the socket is already available, e.g. due to early demux */
988 sk = skb_steal_sock(skb, &refcounted);
989 if (sk) {
990 struct dst_entry *dst = skb_dst(skb);
991 int ret;
992
993 if (unlikely(rcu_dereference(sk->sk_rx_dst) != dst))
994 udp6_sk_rx_dst_set(sk, dst);
995
996 if (!uh->check && !udp_sk(sk)->no_check6_rx) {
997 if (refcounted)
998 sock_put(sk);
999 goto report_csum_error;
1000 }
1001
1002 ret = udp6_unicast_rcv_skb(sk, skb, uh);
1003 if (refcounted)
1004 sock_put(sk);
1005 return ret;
1006 }
1007
1008 /*
1009 * Multicast receive code
1010 */
1011 if (ipv6_addr_is_multicast(daddr))
1012 return __udp6_lib_mcast_deliver(net, skb,
1013 saddr, daddr, udptable, proto);
1014
1015 /* Unicast */
1016 sk = __udp6_lib_lookup_skb(skb, uh->source, uh->dest, udptable);
1017 if (sk) {
1018 if (!uh->check && !udp_sk(sk)->no_check6_rx)
1019 goto report_csum_error;
1020 return udp6_unicast_rcv_skb(sk, skb, uh);
1021 }
1022
1023 reason = SKB_DROP_REASON_NO_SOCKET;
1024
1025 if (!uh->check)
1026 goto report_csum_error;
1027
1028 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
1029 goto discard;
1030
1031 if (udp_lib_checksum_complete(skb))
1032 goto csum_error;
1033
1034 __UDP6_INC_STATS(net, UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE);
1035 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
1036
1037 kfree_skb_reason(skb, reason);
1038 return 0;
1039
1040short_packet:
1041 if (reason == SKB_DROP_REASON_NOT_SPECIFIED)
1042 reason = SKB_DROP_REASON_PKT_TOO_SMALL;
1043 net_dbg_ratelimited("UDP%sv6: short packet: From [%pI6c]:%u %d/%d to [%pI6c]:%u\n",
1044 proto == IPPROTO_UDPLITE ? "-Lite" : "",
1045 saddr, ntohs(uh->source),
1046 ulen, skb->len,
1047 daddr, ntohs(uh->dest));
1048 goto discard;
1049
1050report_csum_error:
1051 udp6_csum_zero_error(skb);
1052csum_error:
1053 if (reason == SKB_DROP_REASON_NOT_SPECIFIED)
1054 reason = SKB_DROP_REASON_UDP_CSUM;
1055 __UDP6_INC_STATS(net, UDP_MIB_CSUMERRORS, proto == IPPROTO_UDPLITE);
1056discard:
1057 __UDP6_INC_STATS(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE);
1058 kfree_skb_reason(skb, reason);
1059 return 0;
1060}
1061
1062
1063static struct sock *__udp6_lib_demux_lookup(struct net *net,
1064 __be16 loc_port, const struct in6_addr *loc_addr,
1065 __be16 rmt_port, const struct in6_addr *rmt_addr,
1066 int dif, int sdif)
1067{
1068 struct udp_table *udptable = net->ipv4.udp_table;
1069 unsigned short hnum = ntohs(loc_port);
1070 unsigned int hash2, slot2;
1071 struct udp_hslot *hslot2;
1072 __portpair ports;
1073 struct sock *sk;
1074
1075 hash2 = ipv6_portaddr_hash(net, loc_addr, hnum);
1076 slot2 = hash2 & udptable->mask;
1077 hslot2 = &udptable->hash2[slot2];
1078 ports = INET_COMBINED_PORTS(rmt_port, hnum);
1079
1080 udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) {
1081 if (sk->sk_state == TCP_ESTABLISHED &&
1082 inet6_match(net, sk, rmt_addr, loc_addr, ports, dif, sdif))
1083 return sk;
1084 /* Only check first socket in chain */
1085 break;
1086 }
1087 return NULL;
1088}
1089
1090void udp_v6_early_demux(struct sk_buff *skb)
1091{
1092 struct net *net = dev_net(skb->dev);
1093 const struct udphdr *uh;
1094 struct sock *sk;
1095 struct dst_entry *dst;
1096 int dif = skb->dev->ifindex;
1097 int sdif = inet6_sdif(skb);
1098
1099 if (!pskb_may_pull(skb, skb_transport_offset(skb) +
1100 sizeof(struct udphdr)))
1101 return;
1102
1103 uh = udp_hdr(skb);
1104
1105 if (skb->pkt_type == PACKET_HOST)
1106 sk = __udp6_lib_demux_lookup(net, uh->dest,
1107 &ipv6_hdr(skb)->daddr,
1108 uh->source, &ipv6_hdr(skb)->saddr,
1109 dif, sdif);
1110 else
1111 return;
1112
1113 if (!sk || !refcount_inc_not_zero(&sk->sk_refcnt))
1114 return;
1115
1116 skb->sk = sk;
1117 skb->destructor = sock_efree;
1118 dst = rcu_dereference(sk->sk_rx_dst);
1119
1120 if (dst)
1121 dst = dst_check(dst, sk->sk_rx_dst_cookie);
1122 if (dst) {
1123 /* set noref for now.
1124 * any place which wants to hold dst has to call
1125 * dst_hold_safe()
1126 */
1127 skb_dst_set_noref(skb, dst);
1128 }
1129}
1130
1131INDIRECT_CALLABLE_SCOPE int udpv6_rcv(struct sk_buff *skb)
1132{
1133 return __udp6_lib_rcv(skb, dev_net(skb->dev)->ipv4.udp_table, IPPROTO_UDP);
1134}
1135
1136/*
1137 * Throw away all pending data and cancel the corking. Socket is locked.
1138 */
1139static void udp_v6_flush_pending_frames(struct sock *sk)
1140{
1141 struct udp_sock *up = udp_sk(sk);
1142
1143 if (up->pending == AF_INET)
1144 udp_flush_pending_frames(sk);
1145 else if (up->pending) {
1146 up->len = 0;
1147 up->pending = 0;
1148 ip6_flush_pending_frames(sk);
1149 }
1150}
1151
1152static int udpv6_pre_connect(struct sock *sk, struct sockaddr *uaddr,
1153 int addr_len)
1154{
1155 if (addr_len < offsetofend(struct sockaddr, sa_family))
1156 return -EINVAL;
1157 /* The following checks are replicated from __ip6_datagram_connect()
1158 * and intended to prevent BPF program called below from accessing
1159 * bytes that are out of the bound specified by user in addr_len.
1160 */
1161 if (uaddr->sa_family == AF_INET) {
1162 if (ipv6_only_sock(sk))
1163 return -EAFNOSUPPORT;
1164 return udp_pre_connect(sk, uaddr, addr_len);
1165 }
1166
1167 if (addr_len < SIN6_LEN_RFC2133)
1168 return -EINVAL;
1169
1170 return BPF_CGROUP_RUN_PROG_INET6_CONNECT_LOCK(sk, uaddr);
1171}
1172
1173/**
1174 * udp6_hwcsum_outgoing - handle outgoing HW checksumming
1175 * @sk: socket we are sending on
1176 * @skb: sk_buff containing the filled-in UDP header
1177 * (checksum field must be zeroed out)
1178 * @saddr: source address
1179 * @daddr: destination address
1180 * @len: length of packet
1181 */
1182static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb,
1183 const struct in6_addr *saddr,
1184 const struct in6_addr *daddr, int len)
1185{
1186 unsigned int offset;
1187 struct udphdr *uh = udp_hdr(skb);
1188 struct sk_buff *frags = skb_shinfo(skb)->frag_list;
1189 __wsum csum = 0;
1190
1191 if (!frags) {
1192 /* Only one fragment on the socket. */
1193 skb->csum_start = skb_transport_header(skb) - skb->head;
1194 skb->csum_offset = offsetof(struct udphdr, check);
1195 uh->check = ~csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 0);
1196 } else {
1197 /*
1198 * HW-checksum won't work as there are two or more
1199 * fragments on the socket so that all csums of sk_buffs
1200 * should be together
1201 */
1202 offset = skb_transport_offset(skb);
1203 skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
1204 csum = skb->csum;
1205
1206 skb->ip_summed = CHECKSUM_NONE;
1207
1208 do {
1209 csum = csum_add(csum, frags->csum);
1210 } while ((frags = frags->next));
1211
1212 uh->check = csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP,
1213 csum);
1214 if (uh->check == 0)
1215 uh->check = CSUM_MANGLED_0;
1216 }
1217}
1218
1219/*
1220 * Sending
1221 */
1222
1223static int udp_v6_send_skb(struct sk_buff *skb, struct flowi6 *fl6,
1224 struct inet_cork *cork)
1225{
1226 struct sock *sk = skb->sk;
1227 struct udphdr *uh;
1228 int err = 0;
1229 int is_udplite = IS_UDPLITE(sk);
1230 __wsum csum = 0;
1231 int offset = skb_transport_offset(skb);
1232 int len = skb->len - offset;
1233 int datalen = len - sizeof(*uh);
1234
1235 /*
1236 * Create a UDP header
1237 */
1238 uh = udp_hdr(skb);
1239 uh->source = fl6->fl6_sport;
1240 uh->dest = fl6->fl6_dport;
1241 uh->len = htons(len);
1242 uh->check = 0;
1243
1244 if (cork->gso_size) {
1245 const int hlen = skb_network_header_len(skb) +
1246 sizeof(struct udphdr);
1247
1248 if (hlen + cork->gso_size > cork->fragsize) {
1249 kfree_skb(skb);
1250 return -EINVAL;
1251 }
1252 if (datalen > cork->gso_size * UDP_MAX_SEGMENTS) {
1253 kfree_skb(skb);
1254 return -EINVAL;
1255 }
1256 if (udp_sk(sk)->no_check6_tx) {
1257 kfree_skb(skb);
1258 return -EINVAL;
1259 }
1260 if (skb->ip_summed != CHECKSUM_PARTIAL || is_udplite ||
1261 dst_xfrm(skb_dst(skb))) {
1262 kfree_skb(skb);
1263 return -EIO;
1264 }
1265
1266 if (datalen > cork->gso_size) {
1267 skb_shinfo(skb)->gso_size = cork->gso_size;
1268 skb_shinfo(skb)->gso_type = SKB_GSO_UDP_L4;
1269 skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(datalen,
1270 cork->gso_size);
1271 }
1272 goto csum_partial;
1273 }
1274
1275 if (is_udplite)
1276 csum = udplite_csum(skb);
1277 else if (udp_sk(sk)->no_check6_tx) { /* UDP csum disabled */
1278 skb->ip_summed = CHECKSUM_NONE;
1279 goto send;
1280 } else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */
1281csum_partial:
1282 udp6_hwcsum_outgoing(sk, skb, &fl6->saddr, &fl6->daddr, len);
1283 goto send;
1284 } else
1285 csum = udp_csum(skb);
1286
1287 /* add protocol-dependent pseudo-header */
1288 uh->check = csum_ipv6_magic(&fl6->saddr, &fl6->daddr,
1289 len, fl6->flowi6_proto, csum);
1290 if (uh->check == 0)
1291 uh->check = CSUM_MANGLED_0;
1292
1293send:
1294 err = ip6_send_skb(skb);
1295 if (err) {
1296 if (err == -ENOBUFS && !inet6_sk(sk)->recverr) {
1297 UDP6_INC_STATS(sock_net(sk),
1298 UDP_MIB_SNDBUFERRORS, is_udplite);
1299 err = 0;
1300 }
1301 } else {
1302 UDP6_INC_STATS(sock_net(sk),
1303 UDP_MIB_OUTDATAGRAMS, is_udplite);
1304 }
1305 return err;
1306}
1307
1308static int udp_v6_push_pending_frames(struct sock *sk)
1309{
1310 struct sk_buff *skb;
1311 struct udp_sock *up = udp_sk(sk);
1312 int err = 0;
1313
1314 if (up->pending == AF_INET)
1315 return udp_push_pending_frames(sk);
1316
1317 skb = ip6_finish_skb(sk);
1318 if (!skb)
1319 goto out;
1320
1321 err = udp_v6_send_skb(skb, &inet_sk(sk)->cork.fl.u.ip6,
1322 &inet_sk(sk)->cork.base);
1323out:
1324 up->len = 0;
1325 up->pending = 0;
1326 return err;
1327}
1328
1329int udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
1330{
1331 struct ipv6_txoptions opt_space;
1332 struct udp_sock *up = udp_sk(sk);
1333 struct inet_sock *inet = inet_sk(sk);
1334 struct ipv6_pinfo *np = inet6_sk(sk);
1335 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
1336 struct in6_addr *daddr, *final_p, final;
1337 struct ipv6_txoptions *opt = NULL;
1338 struct ipv6_txoptions *opt_to_free = NULL;
1339 struct ip6_flowlabel *flowlabel = NULL;
1340 struct inet_cork_full cork;
1341 struct flowi6 *fl6 = &cork.fl.u.ip6;
1342 struct dst_entry *dst;
1343 struct ipcm6_cookie ipc6;
1344 int addr_len = msg->msg_namelen;
1345 bool connected = false;
1346 int ulen = len;
1347 int corkreq = READ_ONCE(up->corkflag) || msg->msg_flags&MSG_MORE;
1348 int err;
1349 int is_udplite = IS_UDPLITE(sk);
1350 int (*getfrag)(void *, char *, int, int, int, struct sk_buff *);
1351
1352 ipcm6_init(&ipc6);
1353 ipc6.gso_size = READ_ONCE(up->gso_size);
1354 ipc6.sockc.tsflags = sk->sk_tsflags;
1355 ipc6.sockc.mark = sk->sk_mark;
1356
1357 /* destination address check */
1358 if (sin6) {
1359 if (addr_len < offsetof(struct sockaddr, sa_data))
1360 return -EINVAL;
1361
1362 switch (sin6->sin6_family) {
1363 case AF_INET6:
1364 if (addr_len < SIN6_LEN_RFC2133)
1365 return -EINVAL;
1366 daddr = &sin6->sin6_addr;
1367 if (ipv6_addr_any(daddr) &&
1368 ipv6_addr_v4mapped(&np->saddr))
1369 ipv6_addr_set_v4mapped(htonl(INADDR_LOOPBACK),
1370 daddr);
1371 break;
1372 case AF_INET:
1373 goto do_udp_sendmsg;
1374 case AF_UNSPEC:
1375 msg->msg_name = sin6 = NULL;
1376 msg->msg_namelen = addr_len = 0;
1377 daddr = NULL;
1378 break;
1379 default:
1380 return -EINVAL;
1381 }
1382 } else if (!up->pending) {
1383 if (sk->sk_state != TCP_ESTABLISHED)
1384 return -EDESTADDRREQ;
1385 daddr = &sk->sk_v6_daddr;
1386 } else
1387 daddr = NULL;
1388
1389 if (daddr) {
1390 if (ipv6_addr_v4mapped(daddr)) {
1391 struct sockaddr_in sin;
1392 sin.sin_family = AF_INET;
1393 sin.sin_port = sin6 ? sin6->sin6_port : inet->inet_dport;
1394 sin.sin_addr.s_addr = daddr->s6_addr32[3];
1395 msg->msg_name = &sin;
1396 msg->msg_namelen = sizeof(sin);
1397do_udp_sendmsg:
1398 if (ipv6_only_sock(sk))
1399 return -ENETUNREACH;
1400 return udp_sendmsg(sk, msg, len);
1401 }
1402 }
1403
1404 /* Rough check on arithmetic overflow,
1405 better check is made in ip6_append_data().
1406 */
1407 if (len > INT_MAX - sizeof(struct udphdr))
1408 return -EMSGSIZE;
1409
1410 getfrag = is_udplite ? udplite_getfrag : ip_generic_getfrag;
1411 if (up->pending) {
1412 if (up->pending == AF_INET)
1413 return udp_sendmsg(sk, msg, len);
1414 /*
1415 * There are pending frames.
1416 * The socket lock must be held while it's corked.
1417 */
1418 lock_sock(sk);
1419 if (likely(up->pending)) {
1420 if (unlikely(up->pending != AF_INET6)) {
1421 release_sock(sk);
1422 return -EAFNOSUPPORT;
1423 }
1424 dst = NULL;
1425 goto do_append_data;
1426 }
1427 release_sock(sk);
1428 }
1429 ulen += sizeof(struct udphdr);
1430
1431 memset(fl6, 0, sizeof(*fl6));
1432
1433 if (sin6) {
1434 if (sin6->sin6_port == 0)
1435 return -EINVAL;
1436
1437 fl6->fl6_dport = sin6->sin6_port;
1438 daddr = &sin6->sin6_addr;
1439
1440 if (np->sndflow) {
1441 fl6->flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK;
1442 if (fl6->flowlabel & IPV6_FLOWLABEL_MASK) {
1443 flowlabel = fl6_sock_lookup(sk, fl6->flowlabel);
1444 if (IS_ERR(flowlabel))
1445 return -EINVAL;
1446 }
1447 }
1448
1449 /*
1450 * Otherwise it will be difficult to maintain
1451 * sk->sk_dst_cache.
1452 */
1453 if (sk->sk_state == TCP_ESTABLISHED &&
1454 ipv6_addr_equal(daddr, &sk->sk_v6_daddr))
1455 daddr = &sk->sk_v6_daddr;
1456
1457 if (addr_len >= sizeof(struct sockaddr_in6) &&
1458 sin6->sin6_scope_id &&
1459 __ipv6_addr_needs_scope_id(__ipv6_addr_type(daddr)))
1460 fl6->flowi6_oif = sin6->sin6_scope_id;
1461 } else {
1462 if (sk->sk_state != TCP_ESTABLISHED)
1463 return -EDESTADDRREQ;
1464
1465 fl6->fl6_dport = inet->inet_dport;
1466 daddr = &sk->sk_v6_daddr;
1467 fl6->flowlabel = np->flow_label;
1468 connected = true;
1469 }
1470
1471 if (!fl6->flowi6_oif)
1472 fl6->flowi6_oif = READ_ONCE(sk->sk_bound_dev_if);
1473
1474 if (!fl6->flowi6_oif)
1475 fl6->flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;
1476
1477 fl6->flowi6_uid = sk->sk_uid;
1478
1479 if (msg->msg_controllen) {
1480 opt = &opt_space;
1481 memset(opt, 0, sizeof(struct ipv6_txoptions));
1482 opt->tot_len = sizeof(*opt);
1483 ipc6.opt = opt;
1484
1485 err = udp_cmsg_send(sk, msg, &ipc6.gso_size);
1486 if (err > 0)
1487 err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, fl6,
1488 &ipc6);
1489 if (err < 0) {
1490 fl6_sock_release(flowlabel);
1491 return err;
1492 }
1493 if ((fl6->flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) {
1494 flowlabel = fl6_sock_lookup(sk, fl6->flowlabel);
1495 if (IS_ERR(flowlabel))
1496 return -EINVAL;
1497 }
1498 if (!(opt->opt_nflen|opt->opt_flen))
1499 opt = NULL;
1500 connected = false;
1501 }
1502 if (!opt) {
1503 opt = txopt_get(np);
1504 opt_to_free = opt;
1505 }
1506 if (flowlabel)
1507 opt = fl6_merge_options(&opt_space, flowlabel, opt);
1508 opt = ipv6_fixup_options(&opt_space, opt);
1509 ipc6.opt = opt;
1510
1511 fl6->flowi6_proto = sk->sk_protocol;
1512 fl6->flowi6_mark = ipc6.sockc.mark;
1513 fl6->daddr = *daddr;
1514 if (ipv6_addr_any(&fl6->saddr) && !ipv6_addr_any(&np->saddr))
1515 fl6->saddr = np->saddr;
1516 fl6->fl6_sport = inet->inet_sport;
1517
1518 if (cgroup_bpf_enabled(CGROUP_UDP6_SENDMSG) && !connected) {
1519 err = BPF_CGROUP_RUN_PROG_UDP6_SENDMSG_LOCK(sk,
1520 (struct sockaddr *)sin6,
1521 &fl6->saddr);
1522 if (err)
1523 goto out_no_dst;
1524 if (sin6) {
1525 if (ipv6_addr_v4mapped(&sin6->sin6_addr)) {
1526 /* BPF program rewrote IPv6-only by IPv4-mapped
1527 * IPv6. It's currently unsupported.
1528 */
1529 err = -ENOTSUPP;
1530 goto out_no_dst;
1531 }
1532 if (sin6->sin6_port == 0) {
1533 /* BPF program set invalid port. Reject it. */
1534 err = -EINVAL;
1535 goto out_no_dst;
1536 }
1537 fl6->fl6_dport = sin6->sin6_port;
1538 fl6->daddr = sin6->sin6_addr;
1539 }
1540 }
1541
1542 if (ipv6_addr_any(&fl6->daddr))
1543 fl6->daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */
1544
1545 final_p = fl6_update_dst(fl6, opt, &final);
1546 if (final_p)
1547 connected = false;
1548
1549 if (!fl6->flowi6_oif && ipv6_addr_is_multicast(&fl6->daddr)) {
1550 fl6->flowi6_oif = np->mcast_oif;
1551 connected = false;
1552 } else if (!fl6->flowi6_oif)
1553 fl6->flowi6_oif = np->ucast_oif;
1554
1555 security_sk_classify_flow(sk, flowi6_to_flowi_common(fl6));
1556
1557 if (ipc6.tclass < 0)
1558 ipc6.tclass = np->tclass;
1559
1560 fl6->flowlabel = ip6_make_flowinfo(ipc6.tclass, fl6->flowlabel);
1561
1562 dst = ip6_sk_dst_lookup_flow(sk, fl6, final_p, connected);
1563 if (IS_ERR(dst)) {
1564 err = PTR_ERR(dst);
1565 dst = NULL;
1566 goto out;
1567 }
1568
1569 if (ipc6.hlimit < 0)
1570 ipc6.hlimit = ip6_sk_dst_hoplimit(np, fl6, dst);
1571
1572 if (msg->msg_flags&MSG_CONFIRM)
1573 goto do_confirm;
1574back_from_confirm:
1575
1576 /* Lockless fast path for the non-corking case */
1577 if (!corkreq) {
1578 struct sk_buff *skb;
1579
1580 skb = ip6_make_skb(sk, getfrag, msg, ulen,
1581 sizeof(struct udphdr), &ipc6,
1582 (struct rt6_info *)dst,
1583 msg->msg_flags, &cork);
1584 err = PTR_ERR(skb);
1585 if (!IS_ERR_OR_NULL(skb))
1586 err = udp_v6_send_skb(skb, fl6, &cork.base);
1587 /* ip6_make_skb steals dst reference */
1588 goto out_no_dst;
1589 }
1590
1591 lock_sock(sk);
1592 if (unlikely(up->pending)) {
1593 /* The socket is already corked while preparing it. */
1594 /* ... which is an evident application bug. --ANK */
1595 release_sock(sk);
1596
1597 net_dbg_ratelimited("udp cork app bug 2\n");
1598 err = -EINVAL;
1599 goto out;
1600 }
1601
1602 up->pending = AF_INET6;
1603
1604do_append_data:
1605 if (ipc6.dontfrag < 0)
1606 ipc6.dontfrag = np->dontfrag;
1607 up->len += ulen;
1608 err = ip6_append_data(sk, getfrag, msg, ulen, sizeof(struct udphdr),
1609 &ipc6, fl6, (struct rt6_info *)dst,
1610 corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags);
1611 if (err)
1612 udp_v6_flush_pending_frames(sk);
1613 else if (!corkreq)
1614 err = udp_v6_push_pending_frames(sk);
1615 else if (unlikely(skb_queue_empty(&sk->sk_write_queue)))
1616 up->pending = 0;
1617
1618 if (err > 0)
1619 err = np->recverr ? net_xmit_errno(err) : 0;
1620 release_sock(sk);
1621
1622out:
1623 dst_release(dst);
1624out_no_dst:
1625 fl6_sock_release(flowlabel);
1626 txopt_put(opt_to_free);
1627 if (!err)
1628 return len;
1629 /*
1630 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space. Reporting
1631 * ENOBUFS might not be good (it's not tunable per se), but otherwise
1632 * we don't have a good statistic (IpOutDiscards but it can be too many
1633 * things). We could add another new stat but at least for now that
1634 * seems like overkill.
1635 */
1636 if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) {
1637 UDP6_INC_STATS(sock_net(sk),
1638 UDP_MIB_SNDBUFERRORS, is_udplite);
1639 }
1640 return err;
1641
1642do_confirm:
1643 if (msg->msg_flags & MSG_PROBE)
1644 dst_confirm_neigh(dst, &fl6->daddr);
1645 if (!(msg->msg_flags&MSG_PROBE) || len)
1646 goto back_from_confirm;
1647 err = 0;
1648 goto out;
1649}
1650EXPORT_SYMBOL(udpv6_sendmsg);
1651
1652void udpv6_destroy_sock(struct sock *sk)
1653{
1654 struct udp_sock *up = udp_sk(sk);
1655 lock_sock(sk);
1656
1657 /* protects from races with udp_abort() */
1658 sock_set_flag(sk, SOCK_DEAD);
1659 udp_v6_flush_pending_frames(sk);
1660 release_sock(sk);
1661
1662 if (static_branch_unlikely(&udpv6_encap_needed_key)) {
1663 if (up->encap_type) {
1664 void (*encap_destroy)(struct sock *sk);
1665 encap_destroy = READ_ONCE(up->encap_destroy);
1666 if (encap_destroy)
1667 encap_destroy(sk);
1668 }
1669 if (up->encap_enabled) {
1670 static_branch_dec(&udpv6_encap_needed_key);
1671 udp_encap_disable();
1672 }
1673 }
1674}
1675
1676/*
1677 * Socket option code for UDP
1678 */
1679int udpv6_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
1680 unsigned int optlen)
1681{
1682 if (level == SOL_UDP || level == SOL_UDPLITE || level == SOL_SOCKET)
1683 return udp_lib_setsockopt(sk, level, optname,
1684 optval, optlen,
1685 udp_v6_push_pending_frames);
1686 return ipv6_setsockopt(sk, level, optname, optval, optlen);
1687}
1688
1689int udpv6_getsockopt(struct sock *sk, int level, int optname,
1690 char __user *optval, int __user *optlen)
1691{
1692 if (level == SOL_UDP || level == SOL_UDPLITE)
1693 return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1694 return ipv6_getsockopt(sk, level, optname, optval, optlen);
1695}
1696
1697static const struct inet6_protocol udpv6_protocol = {
1698 .handler = udpv6_rcv,
1699 .err_handler = udpv6_err,
1700 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1701};
1702
1703/* ------------------------------------------------------------------------ */
1704#ifdef CONFIG_PROC_FS
1705int udp6_seq_show(struct seq_file *seq, void *v)
1706{
1707 if (v == SEQ_START_TOKEN) {
1708 seq_puts(seq, IPV6_SEQ_DGRAM_HEADER);
1709 } else {
1710 int bucket = ((struct udp_iter_state *)seq->private)->bucket;
1711 struct inet_sock *inet = inet_sk(v);
1712 __u16 srcp = ntohs(inet->inet_sport);
1713 __u16 destp = ntohs(inet->inet_dport);
1714 __ip6_dgram_sock_seq_show(seq, v, srcp, destp,
1715 udp_rqueue_get(v), bucket);
1716 }
1717 return 0;
1718}
1719
1720const struct seq_operations udp6_seq_ops = {
1721 .start = udp_seq_start,
1722 .next = udp_seq_next,
1723 .stop = udp_seq_stop,
1724 .show = udp6_seq_show,
1725};
1726EXPORT_SYMBOL(udp6_seq_ops);
1727
1728static struct udp_seq_afinfo udp6_seq_afinfo = {
1729 .family = AF_INET6,
1730 .udp_table = NULL,
1731};
1732
1733int __net_init udp6_proc_init(struct net *net)
1734{
1735 if (!proc_create_net_data("udp6", 0444, net->proc_net, &udp6_seq_ops,
1736 sizeof(struct udp_iter_state), &udp6_seq_afinfo))
1737 return -ENOMEM;
1738 return 0;
1739}
1740
1741void udp6_proc_exit(struct net *net)
1742{
1743 remove_proc_entry("udp6", net->proc_net);
1744}
1745#endif /* CONFIG_PROC_FS */
1746
1747/* ------------------------------------------------------------------------ */
1748
1749struct proto udpv6_prot = {
1750 .name = "UDPv6",
1751 .owner = THIS_MODULE,
1752 .close = udp_lib_close,
1753 .pre_connect = udpv6_pre_connect,
1754 .connect = ip6_datagram_connect,
1755 .disconnect = udp_disconnect,
1756 .ioctl = udp_ioctl,
1757 .init = udpv6_init_sock,
1758 .destroy = udpv6_destroy_sock,
1759 .setsockopt = udpv6_setsockopt,
1760 .getsockopt = udpv6_getsockopt,
1761 .sendmsg = udpv6_sendmsg,
1762 .recvmsg = udpv6_recvmsg,
1763 .release_cb = ip6_datagram_release_cb,
1764 .hash = udp_lib_hash,
1765 .unhash = udp_lib_unhash,
1766 .rehash = udp_v6_rehash,
1767 .get_port = udp_v6_get_port,
1768 .put_port = udp_lib_unhash,
1769#ifdef CONFIG_BPF_SYSCALL
1770 .psock_update_sk_prot = udp_bpf_update_proto,
1771#endif
1772
1773 .memory_allocated = &udp_memory_allocated,
1774 .per_cpu_fw_alloc = &udp_memory_per_cpu_fw_alloc,
1775
1776 .sysctl_mem = sysctl_udp_mem,
1777 .sysctl_wmem_offset = offsetof(struct net, ipv4.sysctl_udp_wmem_min),
1778 .sysctl_rmem_offset = offsetof(struct net, ipv4.sysctl_udp_rmem_min),
1779 .obj_size = sizeof(struct udp6_sock),
1780 .h.udp_table = NULL,
1781 .diag_destroy = udp_abort,
1782};
1783
1784static struct inet_protosw udpv6_protosw = {
1785 .type = SOCK_DGRAM,
1786 .protocol = IPPROTO_UDP,
1787 .prot = &udpv6_prot,
1788 .ops = &inet6_dgram_ops,
1789 .flags = INET_PROTOSW_PERMANENT,
1790};
1791
1792int __init udpv6_init(void)
1793{
1794 int ret;
1795
1796 ret = inet6_add_protocol(&udpv6_protocol, IPPROTO_UDP);
1797 if (ret)
1798 goto out;
1799
1800 ret = inet6_register_protosw(&udpv6_protosw);
1801 if (ret)
1802 goto out_udpv6_protocol;
1803out:
1804 return ret;
1805
1806out_udpv6_protocol:
1807 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1808 goto out;
1809}
1810
1811void udpv6_exit(void)
1812{
1813 inet6_unregister_protosw(&udpv6_protosw);
1814 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1815}