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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 <asm/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/inet6_hashtables.h>
50#include <net/busy_poll.h>
51#include <net/sock_reuseport.h>
52
53#include <linux/proc_fs.h>
54#include <linux/seq_file.h>
55#include <trace/events/skb.h>
56#include "udp_impl.h"
57
58static u32 udp6_ehashfn(const struct net *net,
59 const struct in6_addr *laddr,
60 const u16 lport,
61 const struct in6_addr *faddr,
62 const __be16 fport)
63{
64 static u32 udp6_ehash_secret __read_mostly;
65 static u32 udp_ipv6_hash_secret __read_mostly;
66
67 u32 lhash, fhash;
68
69 net_get_random_once(&udp6_ehash_secret,
70 sizeof(udp6_ehash_secret));
71 net_get_random_once(&udp_ipv6_hash_secret,
72 sizeof(udp_ipv6_hash_secret));
73
74 lhash = (__force u32)laddr->s6_addr32[3];
75 fhash = __ipv6_addr_jhash(faddr, udp_ipv6_hash_secret);
76
77 return __inet6_ehashfn(lhash, lport, fhash, fport,
78 udp_ipv6_hash_secret + net_hash_mix(net));
79}
80
81static u32 udp6_portaddr_hash(const struct net *net,
82 const struct in6_addr *addr6,
83 unsigned int port)
84{
85 unsigned int hash, mix = net_hash_mix(net);
86
87 if (ipv6_addr_any(addr6))
88 hash = jhash_1word(0, mix);
89 else if (ipv6_addr_v4mapped(addr6))
90 hash = jhash_1word((__force u32)addr6->s6_addr32[3], mix);
91 else
92 hash = jhash2((__force u32 *)addr6->s6_addr32, 4, mix);
93
94 return hash ^ port;
95}
96
97int udp_v6_get_port(struct sock *sk, unsigned short snum)
98{
99 unsigned int hash2_nulladdr =
100 udp6_portaddr_hash(sock_net(sk), &in6addr_any, snum);
101 unsigned int hash2_partial =
102 udp6_portaddr_hash(sock_net(sk), &sk->sk_v6_rcv_saddr, 0);
103
104 /* precompute partial secondary hash */
105 udp_sk(sk)->udp_portaddr_hash = hash2_partial;
106 return udp_lib_get_port(sk, snum, ipv6_rcv_saddr_equal, hash2_nulladdr);
107}
108
109static void udp_v6_rehash(struct sock *sk)
110{
111 u16 new_hash = udp6_portaddr_hash(sock_net(sk),
112 &sk->sk_v6_rcv_saddr,
113 inet_sk(sk)->inet_num);
114
115 udp_lib_rehash(sk, new_hash);
116}
117
118static inline int compute_score(struct sock *sk, struct net *net,
119 unsigned short hnum,
120 const struct in6_addr *saddr, __be16 sport,
121 const struct in6_addr *daddr, __be16 dport,
122 int dif)
123{
124 int score;
125 struct inet_sock *inet;
126
127 if (!net_eq(sock_net(sk), net) ||
128 udp_sk(sk)->udp_port_hash != hnum ||
129 sk->sk_family != PF_INET6)
130 return -1;
131
132 score = 0;
133 inet = inet_sk(sk);
134
135 if (inet->inet_dport) {
136 if (inet->inet_dport != sport)
137 return -1;
138 score++;
139 }
140
141 if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr)) {
142 if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
143 return -1;
144 score++;
145 }
146
147 if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
148 if (!ipv6_addr_equal(&sk->sk_v6_daddr, saddr))
149 return -1;
150 score++;
151 }
152
153 if (sk->sk_bound_dev_if) {
154 if (sk->sk_bound_dev_if != dif)
155 return -1;
156 score++;
157 }
158
159 if (sk->sk_incoming_cpu == raw_smp_processor_id())
160 score++;
161
162 return score;
163}
164
165static inline int compute_score2(struct sock *sk, struct net *net,
166 const struct in6_addr *saddr, __be16 sport,
167 const struct in6_addr *daddr,
168 unsigned short hnum, int dif)
169{
170 int score;
171 struct inet_sock *inet;
172
173 if (!net_eq(sock_net(sk), net) ||
174 udp_sk(sk)->udp_port_hash != hnum ||
175 sk->sk_family != PF_INET6)
176 return -1;
177
178 if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
179 return -1;
180
181 score = 0;
182 inet = inet_sk(sk);
183
184 if (inet->inet_dport) {
185 if (inet->inet_dport != sport)
186 return -1;
187 score++;
188 }
189
190 if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
191 if (!ipv6_addr_equal(&sk->sk_v6_daddr, saddr))
192 return -1;
193 score++;
194 }
195
196 if (sk->sk_bound_dev_if) {
197 if (sk->sk_bound_dev_if != dif)
198 return -1;
199 score++;
200 }
201
202 if (sk->sk_incoming_cpu == raw_smp_processor_id())
203 score++;
204
205 return score;
206}
207
208/* called with read_rcu_lock() */
209static struct sock *udp6_lib_lookup2(struct net *net,
210 const struct in6_addr *saddr, __be16 sport,
211 const struct in6_addr *daddr, unsigned int hnum, int dif,
212 struct udp_hslot *hslot2, unsigned int slot2,
213 struct sk_buff *skb)
214{
215 struct sock *sk, *result;
216 struct hlist_nulls_node *node;
217 int score, badness, matches = 0, reuseport = 0;
218 bool select_ok = true;
219 u32 hash = 0;
220
221begin:
222 result = NULL;
223 badness = -1;
224 udp_portaddr_for_each_entry_rcu(sk, node, &hslot2->head) {
225 score = compute_score2(sk, net, saddr, sport,
226 daddr, hnum, dif);
227 if (score > badness) {
228 result = sk;
229 badness = score;
230 reuseport = sk->sk_reuseport;
231 if (reuseport) {
232 hash = udp6_ehashfn(net, daddr, hnum,
233 saddr, sport);
234 if (select_ok) {
235 struct sock *sk2;
236
237 sk2 = reuseport_select_sock(sk, hash, skb,
238 sizeof(struct udphdr));
239 if (sk2) {
240 result = sk2;
241 select_ok = false;
242 goto found;
243 }
244 }
245 matches = 1;
246 }
247 } else if (score == badness && reuseport) {
248 matches++;
249 if (reciprocal_scale(hash, matches) == 0)
250 result = sk;
251 hash = next_pseudo_random32(hash);
252 }
253 }
254 /*
255 * if the nulls value we got at the end of this lookup is
256 * not the expected one, we must restart lookup.
257 * We probably met an item that was moved to another chain.
258 */
259 if (get_nulls_value(node) != slot2)
260 goto begin;
261
262 if (result) {
263found:
264 if (unlikely(!atomic_inc_not_zero_hint(&result->sk_refcnt, 2)))
265 result = NULL;
266 else if (unlikely(compute_score2(result, net, saddr, sport,
267 daddr, hnum, dif) < badness)) {
268 sock_put(result);
269 goto begin;
270 }
271 }
272 return result;
273}
274
275struct sock *__udp6_lib_lookup(struct net *net,
276 const struct in6_addr *saddr, __be16 sport,
277 const struct in6_addr *daddr, __be16 dport,
278 int dif, struct udp_table *udptable,
279 struct sk_buff *skb)
280{
281 struct sock *sk, *result;
282 struct hlist_nulls_node *node;
283 unsigned short hnum = ntohs(dport);
284 unsigned int hash2, slot2, slot = udp_hashfn(net, hnum, udptable->mask);
285 struct udp_hslot *hslot2, *hslot = &udptable->hash[slot];
286 int score, badness, matches = 0, reuseport = 0;
287 bool select_ok = true;
288 u32 hash = 0;
289
290 rcu_read_lock();
291 if (hslot->count > 10) {
292 hash2 = udp6_portaddr_hash(net, daddr, hnum);
293 slot2 = hash2 & udptable->mask;
294 hslot2 = &udptable->hash2[slot2];
295 if (hslot->count < hslot2->count)
296 goto begin;
297
298 result = udp6_lib_lookup2(net, saddr, sport,
299 daddr, hnum, dif,
300 hslot2, slot2, skb);
301 if (!result) {
302 hash2 = udp6_portaddr_hash(net, &in6addr_any, hnum);
303 slot2 = hash2 & udptable->mask;
304 hslot2 = &udptable->hash2[slot2];
305 if (hslot->count < hslot2->count)
306 goto begin;
307
308 result = udp6_lib_lookup2(net, saddr, sport,
309 &in6addr_any, hnum, dif,
310 hslot2, slot2, skb);
311 }
312 rcu_read_unlock();
313 return result;
314 }
315begin:
316 result = NULL;
317 badness = -1;
318 sk_nulls_for_each_rcu(sk, node, &hslot->head) {
319 score = compute_score(sk, net, hnum, saddr, sport, daddr, dport, dif);
320 if (score > badness) {
321 result = sk;
322 badness = score;
323 reuseport = sk->sk_reuseport;
324 if (reuseport) {
325 hash = udp6_ehashfn(net, daddr, hnum,
326 saddr, sport);
327 if (select_ok) {
328 struct sock *sk2;
329
330 sk2 = reuseport_select_sock(sk, hash, skb,
331 sizeof(struct udphdr));
332 if (sk2) {
333 result = sk2;
334 select_ok = false;
335 goto found;
336 }
337 }
338 matches = 1;
339 }
340 } else if (score == badness && reuseport) {
341 matches++;
342 if (reciprocal_scale(hash, matches) == 0)
343 result = sk;
344 hash = next_pseudo_random32(hash);
345 }
346 }
347 /*
348 * if the nulls value we got at the end of this lookup is
349 * not the expected one, we must restart lookup.
350 * We probably met an item that was moved to another chain.
351 */
352 if (get_nulls_value(node) != slot)
353 goto begin;
354
355 if (result) {
356found:
357 if (unlikely(!atomic_inc_not_zero_hint(&result->sk_refcnt, 2)))
358 result = NULL;
359 else if (unlikely(compute_score(result, net, hnum, saddr, sport,
360 daddr, dport, dif) < badness)) {
361 sock_put(result);
362 goto begin;
363 }
364 }
365 rcu_read_unlock();
366 return result;
367}
368EXPORT_SYMBOL_GPL(__udp6_lib_lookup);
369
370static struct sock *__udp6_lib_lookup_skb(struct sk_buff *skb,
371 __be16 sport, __be16 dport,
372 struct udp_table *udptable)
373{
374 struct sock *sk;
375 const struct ipv6hdr *iph = ipv6_hdr(skb);
376
377 sk = skb_steal_sock(skb);
378 if (unlikely(sk))
379 return sk;
380 return __udp6_lib_lookup(dev_net(skb_dst(skb)->dev), &iph->saddr, sport,
381 &iph->daddr, dport, inet6_iif(skb),
382 udptable, skb);
383}
384
385struct sock *udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport,
386 const struct in6_addr *daddr, __be16 dport, int dif)
387{
388 return __udp6_lib_lookup(net, saddr, sport, daddr, dport, dif, &udp_table, NULL);
389}
390EXPORT_SYMBOL_GPL(udp6_lib_lookup);
391
392/*
393 * This should be easy, if there is something there we
394 * return it, otherwise we block.
395 */
396
397int udpv6_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
398 int noblock, int flags, int *addr_len)
399{
400 struct ipv6_pinfo *np = inet6_sk(sk);
401 struct inet_sock *inet = inet_sk(sk);
402 struct sk_buff *skb;
403 unsigned int ulen, copied;
404 int peeked, off = 0;
405 int err;
406 int is_udplite = IS_UDPLITE(sk);
407 bool checksum_valid = false;
408 int is_udp4;
409 bool slow;
410
411 if (flags & MSG_ERRQUEUE)
412 return ipv6_recv_error(sk, msg, len, addr_len);
413
414 if (np->rxpmtu && np->rxopt.bits.rxpmtu)
415 return ipv6_recv_rxpmtu(sk, msg, len, addr_len);
416
417try_again:
418 skb = __skb_recv_datagram(sk, flags | (noblock ? MSG_DONTWAIT : 0),
419 &peeked, &off, &err);
420 if (!skb)
421 goto out;
422
423 ulen = skb->len - sizeof(struct udphdr);
424 copied = len;
425 if (copied > ulen)
426 copied = ulen;
427 else if (copied < ulen)
428 msg->msg_flags |= MSG_TRUNC;
429
430 is_udp4 = (skb->protocol == htons(ETH_P_IP));
431
432 /*
433 * If checksum is needed at all, try to do it while copying the
434 * data. If the data is truncated, or if we only want a partial
435 * coverage checksum (UDP-Lite), do it before the copy.
436 */
437
438 if (copied < ulen || UDP_SKB_CB(skb)->partial_cov) {
439 checksum_valid = !udp_lib_checksum_complete(skb);
440 if (!checksum_valid)
441 goto csum_copy_err;
442 }
443
444 if (checksum_valid || skb_csum_unnecessary(skb))
445 err = skb_copy_datagram_msg(skb, sizeof(struct udphdr),
446 msg, copied);
447 else {
448 err = skb_copy_and_csum_datagram_msg(skb, sizeof(struct udphdr), msg);
449 if (err == -EINVAL)
450 goto csum_copy_err;
451 }
452 if (unlikely(err)) {
453 trace_kfree_skb(skb, udpv6_recvmsg);
454 if (!peeked) {
455 atomic_inc(&sk->sk_drops);
456 if (is_udp4)
457 UDP_INC_STATS_USER(sock_net(sk),
458 UDP_MIB_INERRORS,
459 is_udplite);
460 else
461 UDP6_INC_STATS_USER(sock_net(sk),
462 UDP_MIB_INERRORS,
463 is_udplite);
464 }
465 goto out_free;
466 }
467 if (!peeked) {
468 if (is_udp4)
469 UDP_INC_STATS_USER(sock_net(sk),
470 UDP_MIB_INDATAGRAMS, is_udplite);
471 else
472 UDP6_INC_STATS_USER(sock_net(sk),
473 UDP_MIB_INDATAGRAMS, is_udplite);
474 }
475
476 sock_recv_ts_and_drops(msg, sk, skb);
477
478 /* Copy the address. */
479 if (msg->msg_name) {
480 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
481 sin6->sin6_family = AF_INET6;
482 sin6->sin6_port = udp_hdr(skb)->source;
483 sin6->sin6_flowinfo = 0;
484
485 if (is_udp4) {
486 ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
487 &sin6->sin6_addr);
488 sin6->sin6_scope_id = 0;
489 } else {
490 sin6->sin6_addr = ipv6_hdr(skb)->saddr;
491 sin6->sin6_scope_id =
492 ipv6_iface_scope_id(&sin6->sin6_addr,
493 inet6_iif(skb));
494 }
495 *addr_len = sizeof(*sin6);
496 }
497
498 if (np->rxopt.all)
499 ip6_datagram_recv_common_ctl(sk, msg, skb);
500
501 if (is_udp4) {
502 if (inet->cmsg_flags)
503 ip_cmsg_recv(msg, skb);
504 } else {
505 if (np->rxopt.all)
506 ip6_datagram_recv_specific_ctl(sk, msg, skb);
507 }
508
509 err = copied;
510 if (flags & MSG_TRUNC)
511 err = ulen;
512
513out_free:
514 skb_free_datagram_locked(sk, skb);
515out:
516 return err;
517
518csum_copy_err:
519 slow = lock_sock_fast(sk);
520 if (!skb_kill_datagram(sk, skb, flags)) {
521 if (is_udp4) {
522 UDP_INC_STATS_USER(sock_net(sk),
523 UDP_MIB_CSUMERRORS, is_udplite);
524 UDP_INC_STATS_USER(sock_net(sk),
525 UDP_MIB_INERRORS, is_udplite);
526 } else {
527 UDP6_INC_STATS_USER(sock_net(sk),
528 UDP_MIB_CSUMERRORS, is_udplite);
529 UDP6_INC_STATS_USER(sock_net(sk),
530 UDP_MIB_INERRORS, is_udplite);
531 }
532 }
533 unlock_sock_fast(sk, slow);
534
535 /* starting over for a new packet, but check if we need to yield */
536 cond_resched();
537 msg->msg_flags &= ~MSG_TRUNC;
538 goto try_again;
539}
540
541void __udp6_lib_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
542 u8 type, u8 code, int offset, __be32 info,
543 struct udp_table *udptable)
544{
545 struct ipv6_pinfo *np;
546 const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data;
547 const struct in6_addr *saddr = &hdr->saddr;
548 const struct in6_addr *daddr = &hdr->daddr;
549 struct udphdr *uh = (struct udphdr *)(skb->data+offset);
550 struct sock *sk;
551 int harderr;
552 int err;
553 struct net *net = dev_net(skb->dev);
554
555 sk = __udp6_lib_lookup(net, daddr, uh->dest, saddr, uh->source,
556 inet6_iif(skb), udptable, skb);
557 if (!sk) {
558 ICMP6_INC_STATS_BH(net, __in6_dev_get(skb->dev),
559 ICMP6_MIB_INERRORS);
560 return;
561 }
562
563 harderr = icmpv6_err_convert(type, code, &err);
564 np = inet6_sk(sk);
565
566 if (type == ICMPV6_PKT_TOOBIG) {
567 if (!ip6_sk_accept_pmtu(sk))
568 goto out;
569 ip6_sk_update_pmtu(skb, sk, info);
570 if (np->pmtudisc != IPV6_PMTUDISC_DONT)
571 harderr = 1;
572 }
573 if (type == NDISC_REDIRECT) {
574 ip6_sk_redirect(skb, sk);
575 goto out;
576 }
577
578 if (!np->recverr) {
579 if (!harderr || sk->sk_state != TCP_ESTABLISHED)
580 goto out;
581 } else {
582 ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1));
583 }
584
585 sk->sk_err = err;
586 sk->sk_error_report(sk);
587out:
588 sock_put(sk);
589}
590
591static int __udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
592{
593 int rc;
594
595 if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
596 sock_rps_save_rxhash(sk, skb);
597 sk_mark_napi_id(sk, skb);
598 sk_incoming_cpu_update(sk);
599 }
600
601 rc = sock_queue_rcv_skb(sk, skb);
602 if (rc < 0) {
603 int is_udplite = IS_UDPLITE(sk);
604
605 /* Note that an ENOMEM error is charged twice */
606 if (rc == -ENOMEM)
607 UDP6_INC_STATS_BH(sock_net(sk),
608 UDP_MIB_RCVBUFERRORS, is_udplite);
609 UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
610 kfree_skb(skb);
611 return -1;
612 }
613 return 0;
614}
615
616static __inline__ void udpv6_err(struct sk_buff *skb,
617 struct inet6_skb_parm *opt, u8 type,
618 u8 code, int offset, __be32 info)
619{
620 __udp6_lib_err(skb, opt, type, code, offset, info, &udp_table);
621}
622
623static struct static_key udpv6_encap_needed __read_mostly;
624void udpv6_encap_enable(void)
625{
626 if (!static_key_enabled(&udpv6_encap_needed))
627 static_key_slow_inc(&udpv6_encap_needed);
628}
629EXPORT_SYMBOL(udpv6_encap_enable);
630
631int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
632{
633 struct udp_sock *up = udp_sk(sk);
634 int rc;
635 int is_udplite = IS_UDPLITE(sk);
636
637 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
638 goto drop;
639
640 if (static_key_false(&udpv6_encap_needed) && up->encap_type) {
641 int (*encap_rcv)(struct sock *sk, struct sk_buff *skb);
642
643 /*
644 * This is an encapsulation socket so pass the skb to
645 * the socket's udp_encap_rcv() hook. Otherwise, just
646 * fall through and pass this up the UDP socket.
647 * up->encap_rcv() returns the following value:
648 * =0 if skb was successfully passed to the encap
649 * handler or was discarded by it.
650 * >0 if skb should be passed on to UDP.
651 * <0 if skb should be resubmitted as proto -N
652 */
653
654 /* if we're overly short, let UDP handle it */
655 encap_rcv = ACCESS_ONCE(up->encap_rcv);
656 if (skb->len > sizeof(struct udphdr) && encap_rcv) {
657 int ret;
658
659 /* Verify checksum before giving to encap */
660 if (udp_lib_checksum_complete(skb))
661 goto csum_error;
662
663 ret = encap_rcv(sk, skb);
664 if (ret <= 0) {
665 UDP_INC_STATS_BH(sock_net(sk),
666 UDP_MIB_INDATAGRAMS,
667 is_udplite);
668 return -ret;
669 }
670 }
671
672 /* FALLTHROUGH -- it's a UDP Packet */
673 }
674
675 /*
676 * UDP-Lite specific tests, ignored on UDP sockets (see net/ipv4/udp.c).
677 */
678 if ((is_udplite & UDPLITE_RECV_CC) && UDP_SKB_CB(skb)->partial_cov) {
679
680 if (up->pcrlen == 0) { /* full coverage was set */
681 net_dbg_ratelimited("UDPLITE6: partial coverage %d while full coverage %d requested\n",
682 UDP_SKB_CB(skb)->cscov, skb->len);
683 goto drop;
684 }
685 if (UDP_SKB_CB(skb)->cscov < up->pcrlen) {
686 net_dbg_ratelimited("UDPLITE6: coverage %d too small, need min %d\n",
687 UDP_SKB_CB(skb)->cscov, up->pcrlen);
688 goto drop;
689 }
690 }
691
692 if (rcu_access_pointer(sk->sk_filter)) {
693 if (udp_lib_checksum_complete(skb))
694 goto csum_error;
695 }
696
697 if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
698 UDP6_INC_STATS_BH(sock_net(sk),
699 UDP_MIB_RCVBUFERRORS, is_udplite);
700 goto drop;
701 }
702
703 skb_dst_drop(skb);
704
705 bh_lock_sock(sk);
706 rc = 0;
707 if (!sock_owned_by_user(sk))
708 rc = __udpv6_queue_rcv_skb(sk, skb);
709 else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) {
710 bh_unlock_sock(sk);
711 goto drop;
712 }
713 bh_unlock_sock(sk);
714
715 return rc;
716
717csum_error:
718 UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite);
719drop:
720 UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
721 atomic_inc(&sk->sk_drops);
722 kfree_skb(skb);
723 return -1;
724}
725
726static bool __udp_v6_is_mcast_sock(struct net *net, struct sock *sk,
727 __be16 loc_port, const struct in6_addr *loc_addr,
728 __be16 rmt_port, const struct in6_addr *rmt_addr,
729 int dif, unsigned short hnum)
730{
731 struct inet_sock *inet = inet_sk(sk);
732
733 if (!net_eq(sock_net(sk), net))
734 return false;
735
736 if (udp_sk(sk)->udp_port_hash != hnum ||
737 sk->sk_family != PF_INET6 ||
738 (inet->inet_dport && inet->inet_dport != rmt_port) ||
739 (!ipv6_addr_any(&sk->sk_v6_daddr) &&
740 !ipv6_addr_equal(&sk->sk_v6_daddr, rmt_addr)) ||
741 (sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif) ||
742 (!ipv6_addr_any(&sk->sk_v6_rcv_saddr) &&
743 !ipv6_addr_equal(&sk->sk_v6_rcv_saddr, loc_addr)))
744 return false;
745 if (!inet6_mc_check(sk, loc_addr, rmt_addr))
746 return false;
747 return true;
748}
749
750static void flush_stack(struct sock **stack, unsigned int count,
751 struct sk_buff *skb, unsigned int final)
752{
753 struct sk_buff *skb1 = NULL;
754 struct sock *sk;
755 unsigned int i;
756
757 for (i = 0; i < count; i++) {
758 sk = stack[i];
759 if (likely(!skb1))
760 skb1 = (i == final) ? skb : skb_clone(skb, GFP_ATOMIC);
761 if (!skb1) {
762 atomic_inc(&sk->sk_drops);
763 UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_RCVBUFERRORS,
764 IS_UDPLITE(sk));
765 UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS,
766 IS_UDPLITE(sk));
767 }
768
769 if (skb1 && udpv6_queue_rcv_skb(sk, skb1) <= 0)
770 skb1 = NULL;
771 sock_put(sk);
772 }
773 if (unlikely(skb1))
774 kfree_skb(skb1);
775}
776
777static void udp6_csum_zero_error(struct sk_buff *skb)
778{
779 /* RFC 2460 section 8.1 says that we SHOULD log
780 * this error. Well, it is reasonable.
781 */
782 net_dbg_ratelimited("IPv6: udp checksum is 0 for [%pI6c]:%u->[%pI6c]:%u\n",
783 &ipv6_hdr(skb)->saddr, ntohs(udp_hdr(skb)->source),
784 &ipv6_hdr(skb)->daddr, ntohs(udp_hdr(skb)->dest));
785}
786
787/*
788 * Note: called only from the BH handler context,
789 * so we don't need to lock the hashes.
790 */
791static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
792 const struct in6_addr *saddr, const struct in6_addr *daddr,
793 struct udp_table *udptable, int proto)
794{
795 struct sock *sk, *stack[256 / sizeof(struct sock *)];
796 const struct udphdr *uh = udp_hdr(skb);
797 struct hlist_nulls_node *node;
798 unsigned short hnum = ntohs(uh->dest);
799 struct udp_hslot *hslot = udp_hashslot(udptable, net, hnum);
800 int dif = inet6_iif(skb);
801 unsigned int count = 0, offset = offsetof(typeof(*sk), sk_nulls_node);
802 unsigned int hash2 = 0, hash2_any = 0, use_hash2 = (hslot->count > 10);
803 bool inner_flushed = false;
804
805 if (use_hash2) {
806 hash2_any = udp6_portaddr_hash(net, &in6addr_any, hnum) &
807 udp_table.mask;
808 hash2 = udp6_portaddr_hash(net, daddr, hnum) & udp_table.mask;
809start_lookup:
810 hslot = &udp_table.hash2[hash2];
811 offset = offsetof(typeof(*sk), __sk_common.skc_portaddr_node);
812 }
813
814 spin_lock(&hslot->lock);
815 sk_nulls_for_each_entry_offset(sk, node, &hslot->head, offset) {
816 if (__udp_v6_is_mcast_sock(net, sk,
817 uh->dest, daddr,
818 uh->source, saddr,
819 dif, hnum) &&
820 /* If zero checksum and no_check is not on for
821 * the socket then skip it.
822 */
823 (uh->check || udp_sk(sk)->no_check6_rx)) {
824 if (unlikely(count == ARRAY_SIZE(stack))) {
825 flush_stack(stack, count, skb, ~0);
826 inner_flushed = true;
827 count = 0;
828 }
829 stack[count++] = sk;
830 sock_hold(sk);
831 }
832 }
833
834 spin_unlock(&hslot->lock);
835
836 /* Also lookup *:port if we are using hash2 and haven't done so yet. */
837 if (use_hash2 && hash2 != hash2_any) {
838 hash2 = hash2_any;
839 goto start_lookup;
840 }
841
842 if (count) {
843 flush_stack(stack, count, skb, count - 1);
844 } else {
845 if (!inner_flushed)
846 UDP6_INC_STATS_BH(net, UDP_MIB_IGNOREDMULTI,
847 proto == IPPROTO_UDPLITE);
848 consume_skb(skb);
849 }
850 return 0;
851}
852
853int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
854 int proto)
855{
856 struct net *net = dev_net(skb->dev);
857 struct sock *sk;
858 struct udphdr *uh;
859 const struct in6_addr *saddr, *daddr;
860 u32 ulen = 0;
861
862 if (!pskb_may_pull(skb, sizeof(struct udphdr)))
863 goto discard;
864
865 saddr = &ipv6_hdr(skb)->saddr;
866 daddr = &ipv6_hdr(skb)->daddr;
867 uh = udp_hdr(skb);
868
869 ulen = ntohs(uh->len);
870 if (ulen > skb->len)
871 goto short_packet;
872
873 if (proto == IPPROTO_UDP) {
874 /* UDP validates ulen. */
875
876 /* Check for jumbo payload */
877 if (ulen == 0)
878 ulen = skb->len;
879
880 if (ulen < sizeof(*uh))
881 goto short_packet;
882
883 if (ulen < skb->len) {
884 if (pskb_trim_rcsum(skb, ulen))
885 goto short_packet;
886 saddr = &ipv6_hdr(skb)->saddr;
887 daddr = &ipv6_hdr(skb)->daddr;
888 uh = udp_hdr(skb);
889 }
890 }
891
892 if (udp6_csum_init(skb, uh, proto))
893 goto csum_error;
894
895 /*
896 * Multicast receive code
897 */
898 if (ipv6_addr_is_multicast(daddr))
899 return __udp6_lib_mcast_deliver(net, skb,
900 saddr, daddr, udptable, proto);
901
902 /* Unicast */
903
904 /*
905 * check socket cache ... must talk to Alan about his plans
906 * for sock caches... i'll skip this for now.
907 */
908 sk = __udp6_lib_lookup_skb(skb, uh->source, uh->dest, udptable);
909 if (sk) {
910 int ret;
911
912 if (!uh->check && !udp_sk(sk)->no_check6_rx) {
913 sock_put(sk);
914 udp6_csum_zero_error(skb);
915 goto csum_error;
916 }
917
918 if (inet_get_convert_csum(sk) && uh->check && !IS_UDPLITE(sk))
919 skb_checksum_try_convert(skb, IPPROTO_UDP, uh->check,
920 ip6_compute_pseudo);
921
922 ret = udpv6_queue_rcv_skb(sk, skb);
923 sock_put(sk);
924
925 /* a return value > 0 means to resubmit the input */
926 if (ret > 0)
927 return ret;
928
929 return 0;
930 }
931
932 if (!uh->check) {
933 udp6_csum_zero_error(skb);
934 goto csum_error;
935 }
936
937 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
938 goto discard;
939
940 if (udp_lib_checksum_complete(skb))
941 goto csum_error;
942
943 UDP6_INC_STATS_BH(net, UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE);
944 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
945
946 kfree_skb(skb);
947 return 0;
948
949short_packet:
950 net_dbg_ratelimited("UDP%sv6: short packet: From [%pI6c]:%u %d/%d to [%pI6c]:%u\n",
951 proto == IPPROTO_UDPLITE ? "-Lite" : "",
952 saddr, ntohs(uh->source),
953 ulen, skb->len,
954 daddr, ntohs(uh->dest));
955 goto discard;
956csum_error:
957 UDP6_INC_STATS_BH(net, UDP_MIB_CSUMERRORS, proto == IPPROTO_UDPLITE);
958discard:
959 UDP6_INC_STATS_BH(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE);
960 kfree_skb(skb);
961 return 0;
962}
963
964static __inline__ int udpv6_rcv(struct sk_buff *skb)
965{
966 return __udp6_lib_rcv(skb, &udp_table, IPPROTO_UDP);
967}
968
969/*
970 * Throw away all pending data and cancel the corking. Socket is locked.
971 */
972static void udp_v6_flush_pending_frames(struct sock *sk)
973{
974 struct udp_sock *up = udp_sk(sk);
975
976 if (up->pending == AF_INET)
977 udp_flush_pending_frames(sk);
978 else if (up->pending) {
979 up->len = 0;
980 up->pending = 0;
981 ip6_flush_pending_frames(sk);
982 }
983}
984
985/**
986 * udp6_hwcsum_outgoing - handle outgoing HW checksumming
987 * @sk: socket we are sending on
988 * @skb: sk_buff containing the filled-in UDP header
989 * (checksum field must be zeroed out)
990 */
991static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb,
992 const struct in6_addr *saddr,
993 const struct in6_addr *daddr, int len)
994{
995 unsigned int offset;
996 struct udphdr *uh = udp_hdr(skb);
997 struct sk_buff *frags = skb_shinfo(skb)->frag_list;
998 __wsum csum = 0;
999
1000 if (!frags) {
1001 /* Only one fragment on the socket. */
1002 skb->csum_start = skb_transport_header(skb) - skb->head;
1003 skb->csum_offset = offsetof(struct udphdr, check);
1004 uh->check = ~csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 0);
1005 } else {
1006 /*
1007 * HW-checksum won't work as there are two or more
1008 * fragments on the socket so that all csums of sk_buffs
1009 * should be together
1010 */
1011 offset = skb_transport_offset(skb);
1012 skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
1013
1014 skb->ip_summed = CHECKSUM_NONE;
1015
1016 do {
1017 csum = csum_add(csum, frags->csum);
1018 } while ((frags = frags->next));
1019
1020 uh->check = csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP,
1021 csum);
1022 if (uh->check == 0)
1023 uh->check = CSUM_MANGLED_0;
1024 }
1025}
1026
1027/*
1028 * Sending
1029 */
1030
1031static int udp_v6_send_skb(struct sk_buff *skb, struct flowi6 *fl6)
1032{
1033 struct sock *sk = skb->sk;
1034 struct udphdr *uh;
1035 int err = 0;
1036 int is_udplite = IS_UDPLITE(sk);
1037 __wsum csum = 0;
1038 int offset = skb_transport_offset(skb);
1039 int len = skb->len - offset;
1040
1041 /*
1042 * Create a UDP header
1043 */
1044 uh = udp_hdr(skb);
1045 uh->source = fl6->fl6_sport;
1046 uh->dest = fl6->fl6_dport;
1047 uh->len = htons(len);
1048 uh->check = 0;
1049
1050 if (is_udplite)
1051 csum = udplite_csum(skb);
1052 else if (udp_sk(sk)->no_check6_tx) { /* UDP csum disabled */
1053 skb->ip_summed = CHECKSUM_NONE;
1054 goto send;
1055 } else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */
1056 udp6_hwcsum_outgoing(sk, skb, &fl6->saddr, &fl6->daddr, len);
1057 goto send;
1058 } else
1059 csum = udp_csum(skb);
1060
1061 /* add protocol-dependent pseudo-header */
1062 uh->check = csum_ipv6_magic(&fl6->saddr, &fl6->daddr,
1063 len, fl6->flowi6_proto, csum);
1064 if (uh->check == 0)
1065 uh->check = CSUM_MANGLED_0;
1066
1067send:
1068 err = ip6_send_skb(skb);
1069 if (err) {
1070 if (err == -ENOBUFS && !inet6_sk(sk)->recverr) {
1071 UDP6_INC_STATS_USER(sock_net(sk),
1072 UDP_MIB_SNDBUFERRORS, is_udplite);
1073 err = 0;
1074 }
1075 } else
1076 UDP6_INC_STATS_USER(sock_net(sk),
1077 UDP_MIB_OUTDATAGRAMS, is_udplite);
1078 return err;
1079}
1080
1081static int udp_v6_push_pending_frames(struct sock *sk)
1082{
1083 struct sk_buff *skb;
1084 struct udp_sock *up = udp_sk(sk);
1085 struct flowi6 fl6;
1086 int err = 0;
1087
1088 if (up->pending == AF_INET)
1089 return udp_push_pending_frames(sk);
1090
1091 /* ip6_finish_skb will release the cork, so make a copy of
1092 * fl6 here.
1093 */
1094 fl6 = inet_sk(sk)->cork.fl.u.ip6;
1095
1096 skb = ip6_finish_skb(sk);
1097 if (!skb)
1098 goto out;
1099
1100 err = udp_v6_send_skb(skb, &fl6);
1101
1102out:
1103 up->len = 0;
1104 up->pending = 0;
1105 return err;
1106}
1107
1108int udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
1109{
1110 struct ipv6_txoptions opt_space;
1111 struct udp_sock *up = udp_sk(sk);
1112 struct inet_sock *inet = inet_sk(sk);
1113 struct ipv6_pinfo *np = inet6_sk(sk);
1114 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
1115 struct in6_addr *daddr, *final_p, final;
1116 struct ipv6_txoptions *opt = NULL;
1117 struct ipv6_txoptions *opt_to_free = NULL;
1118 struct ip6_flowlabel *flowlabel = NULL;
1119 struct flowi6 fl6;
1120 struct dst_entry *dst;
1121 int addr_len = msg->msg_namelen;
1122 int ulen = len;
1123 int hlimit = -1;
1124 int tclass = -1;
1125 int dontfrag = -1;
1126 int corkreq = up->corkflag || msg->msg_flags&MSG_MORE;
1127 int err;
1128 int connected = 0;
1129 int is_udplite = IS_UDPLITE(sk);
1130 int (*getfrag)(void *, char *, int, int, int, struct sk_buff *);
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 break;
1143 case AF_INET:
1144 goto do_udp_sendmsg;
1145 case AF_UNSPEC:
1146 msg->msg_name = sin6 = NULL;
1147 msg->msg_namelen = addr_len = 0;
1148 daddr = NULL;
1149 break;
1150 default:
1151 return -EINVAL;
1152 }
1153 } else if (!up->pending) {
1154 if (sk->sk_state != TCP_ESTABLISHED)
1155 return -EDESTADDRREQ;
1156 daddr = &sk->sk_v6_daddr;
1157 } else
1158 daddr = NULL;
1159
1160 if (daddr) {
1161 if (ipv6_addr_v4mapped(daddr)) {
1162 struct sockaddr_in sin;
1163 sin.sin_family = AF_INET;
1164 sin.sin_port = sin6 ? sin6->sin6_port : inet->inet_dport;
1165 sin.sin_addr.s_addr = daddr->s6_addr32[3];
1166 msg->msg_name = &sin;
1167 msg->msg_namelen = sizeof(sin);
1168do_udp_sendmsg:
1169 if (__ipv6_only_sock(sk))
1170 return -ENETUNREACH;
1171 return udp_sendmsg(sk, msg, len);
1172 }
1173 }
1174
1175 if (up->pending == AF_INET)
1176 return udp_sendmsg(sk, msg, len);
1177
1178 /* Rough check on arithmetic overflow,
1179 better check is made in ip6_append_data().
1180 */
1181 if (len > INT_MAX - sizeof(struct udphdr))
1182 return -EMSGSIZE;
1183
1184 getfrag = is_udplite ? udplite_getfrag : ip_generic_getfrag;
1185 if (up->pending) {
1186 /*
1187 * There are pending frames.
1188 * The socket lock must be held while it's corked.
1189 */
1190 lock_sock(sk);
1191 if (likely(up->pending)) {
1192 if (unlikely(up->pending != AF_INET6)) {
1193 release_sock(sk);
1194 return -EAFNOSUPPORT;
1195 }
1196 dst = NULL;
1197 goto do_append_data;
1198 }
1199 release_sock(sk);
1200 }
1201 ulen += sizeof(struct udphdr);
1202
1203 memset(&fl6, 0, sizeof(fl6));
1204
1205 if (sin6) {
1206 if (sin6->sin6_port == 0)
1207 return -EINVAL;
1208
1209 fl6.fl6_dport = sin6->sin6_port;
1210 daddr = &sin6->sin6_addr;
1211
1212 if (np->sndflow) {
1213 fl6.flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK;
1214 if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) {
1215 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1216 if (!flowlabel)
1217 return -EINVAL;
1218 }
1219 }
1220
1221 /*
1222 * Otherwise it will be difficult to maintain
1223 * sk->sk_dst_cache.
1224 */
1225 if (sk->sk_state == TCP_ESTABLISHED &&
1226 ipv6_addr_equal(daddr, &sk->sk_v6_daddr))
1227 daddr = &sk->sk_v6_daddr;
1228
1229 if (addr_len >= sizeof(struct sockaddr_in6) &&
1230 sin6->sin6_scope_id &&
1231 __ipv6_addr_needs_scope_id(__ipv6_addr_type(daddr)))
1232 fl6.flowi6_oif = sin6->sin6_scope_id;
1233 } else {
1234 if (sk->sk_state != TCP_ESTABLISHED)
1235 return -EDESTADDRREQ;
1236
1237 fl6.fl6_dport = inet->inet_dport;
1238 daddr = &sk->sk_v6_daddr;
1239 fl6.flowlabel = np->flow_label;
1240 connected = 1;
1241 }
1242
1243 if (!fl6.flowi6_oif)
1244 fl6.flowi6_oif = sk->sk_bound_dev_if;
1245
1246 if (!fl6.flowi6_oif)
1247 fl6.flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;
1248
1249 fl6.flowi6_mark = sk->sk_mark;
1250
1251 if (msg->msg_controllen) {
1252 opt = &opt_space;
1253 memset(opt, 0, sizeof(struct ipv6_txoptions));
1254 opt->tot_len = sizeof(*opt);
1255
1256 err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, &fl6, opt,
1257 &hlimit, &tclass, &dontfrag);
1258 if (err < 0) {
1259 fl6_sock_release(flowlabel);
1260 return err;
1261 }
1262 if ((fl6.flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) {
1263 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1264 if (!flowlabel)
1265 return -EINVAL;
1266 }
1267 if (!(opt->opt_nflen|opt->opt_flen))
1268 opt = NULL;
1269 connected = 0;
1270 }
1271 if (!opt) {
1272 opt = txopt_get(np);
1273 opt_to_free = opt;
1274 }
1275 if (flowlabel)
1276 opt = fl6_merge_options(&opt_space, flowlabel, opt);
1277 opt = ipv6_fixup_options(&opt_space, opt);
1278
1279 fl6.flowi6_proto = sk->sk_protocol;
1280 if (!ipv6_addr_any(daddr))
1281 fl6.daddr = *daddr;
1282 else
1283 fl6.daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */
1284 if (ipv6_addr_any(&fl6.saddr) && !ipv6_addr_any(&np->saddr))
1285 fl6.saddr = np->saddr;
1286 fl6.fl6_sport = inet->inet_sport;
1287
1288 final_p = fl6_update_dst(&fl6, opt, &final);
1289 if (final_p)
1290 connected = 0;
1291
1292 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr)) {
1293 fl6.flowi6_oif = np->mcast_oif;
1294 connected = 0;
1295 } else if (!fl6.flowi6_oif)
1296 fl6.flowi6_oif = np->ucast_oif;
1297
1298 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
1299
1300 dst = ip6_sk_dst_lookup_flow(sk, &fl6, final_p);
1301 if (IS_ERR(dst)) {
1302 err = PTR_ERR(dst);
1303 dst = NULL;
1304 goto out;
1305 }
1306
1307 if (hlimit < 0)
1308 hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
1309
1310 if (tclass < 0)
1311 tclass = np->tclass;
1312
1313 if (msg->msg_flags&MSG_CONFIRM)
1314 goto do_confirm;
1315back_from_confirm:
1316
1317 /* Lockless fast path for the non-corking case */
1318 if (!corkreq) {
1319 struct sk_buff *skb;
1320
1321 skb = ip6_make_skb(sk, getfrag, msg, ulen,
1322 sizeof(struct udphdr), hlimit, tclass, opt,
1323 &fl6, (struct rt6_info *)dst,
1324 msg->msg_flags, dontfrag);
1325 err = PTR_ERR(skb);
1326 if (!IS_ERR_OR_NULL(skb))
1327 err = udp_v6_send_skb(skb, &fl6);
1328 goto release_dst;
1329 }
1330
1331 lock_sock(sk);
1332 if (unlikely(up->pending)) {
1333 /* The socket is already corked while preparing it. */
1334 /* ... which is an evident application bug. --ANK */
1335 release_sock(sk);
1336
1337 net_dbg_ratelimited("udp cork app bug 2\n");
1338 err = -EINVAL;
1339 goto out;
1340 }
1341
1342 up->pending = AF_INET6;
1343
1344do_append_data:
1345 if (dontfrag < 0)
1346 dontfrag = np->dontfrag;
1347 up->len += ulen;
1348 err = ip6_append_data(sk, getfrag, msg, ulen,
1349 sizeof(struct udphdr), hlimit, tclass, opt, &fl6,
1350 (struct rt6_info *)dst,
1351 corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags, dontfrag);
1352 if (err)
1353 udp_v6_flush_pending_frames(sk);
1354 else if (!corkreq)
1355 err = udp_v6_push_pending_frames(sk);
1356 else if (unlikely(skb_queue_empty(&sk->sk_write_queue)))
1357 up->pending = 0;
1358
1359 if (err > 0)
1360 err = np->recverr ? net_xmit_errno(err) : 0;
1361 release_sock(sk);
1362
1363release_dst:
1364 if (dst) {
1365 if (connected) {
1366 ip6_dst_store(sk, dst,
1367 ipv6_addr_equal(&fl6.daddr, &sk->sk_v6_daddr) ?
1368 &sk->sk_v6_daddr : NULL,
1369#ifdef CONFIG_IPV6_SUBTREES
1370 ipv6_addr_equal(&fl6.saddr, &np->saddr) ?
1371 &np->saddr :
1372#endif
1373 NULL);
1374 } else {
1375 dst_release(dst);
1376 }
1377 dst = NULL;
1378 }
1379
1380out:
1381 dst_release(dst);
1382 fl6_sock_release(flowlabel);
1383 txopt_put(opt_to_free);
1384 if (!err)
1385 return len;
1386 /*
1387 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space. Reporting
1388 * ENOBUFS might not be good (it's not tunable per se), but otherwise
1389 * we don't have a good statistic (IpOutDiscards but it can be too many
1390 * things). We could add another new stat but at least for now that
1391 * seems like overkill.
1392 */
1393 if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) {
1394 UDP6_INC_STATS_USER(sock_net(sk),
1395 UDP_MIB_SNDBUFERRORS, is_udplite);
1396 }
1397 return err;
1398
1399do_confirm:
1400 dst_confirm(dst);
1401 if (!(msg->msg_flags&MSG_PROBE) || len)
1402 goto back_from_confirm;
1403 err = 0;
1404 goto out;
1405}
1406
1407void udpv6_destroy_sock(struct sock *sk)
1408{
1409 struct udp_sock *up = udp_sk(sk);
1410 lock_sock(sk);
1411 udp_v6_flush_pending_frames(sk);
1412 release_sock(sk);
1413
1414 if (static_key_false(&udpv6_encap_needed) && up->encap_type) {
1415 void (*encap_destroy)(struct sock *sk);
1416 encap_destroy = ACCESS_ONCE(up->encap_destroy);
1417 if (encap_destroy)
1418 encap_destroy(sk);
1419 }
1420
1421 inet6_destroy_sock(sk);
1422}
1423
1424/*
1425 * Socket option code for UDP
1426 */
1427int udpv6_setsockopt(struct sock *sk, int level, int optname,
1428 char __user *optval, unsigned int optlen)
1429{
1430 if (level == SOL_UDP || level == SOL_UDPLITE)
1431 return udp_lib_setsockopt(sk, level, optname, optval, optlen,
1432 udp_v6_push_pending_frames);
1433 return ipv6_setsockopt(sk, level, optname, optval, optlen);
1434}
1435
1436#ifdef CONFIG_COMPAT
1437int compat_udpv6_setsockopt(struct sock *sk, int level, int optname,
1438 char __user *optval, unsigned int optlen)
1439{
1440 if (level == SOL_UDP || level == SOL_UDPLITE)
1441 return udp_lib_setsockopt(sk, level, optname, optval, optlen,
1442 udp_v6_push_pending_frames);
1443 return compat_ipv6_setsockopt(sk, level, optname, optval, optlen);
1444}
1445#endif
1446
1447int 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 ipv6_getsockopt(sk, level, optname, optval, optlen);
1453}
1454
1455#ifdef CONFIG_COMPAT
1456int compat_udpv6_getsockopt(struct sock *sk, int level, int optname,
1457 char __user *optval, int __user *optlen)
1458{
1459 if (level == SOL_UDP || level == SOL_UDPLITE)
1460 return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1461 return compat_ipv6_getsockopt(sk, level, optname, optval, optlen);
1462}
1463#endif
1464
1465static const struct inet6_protocol udpv6_protocol = {
1466 .handler = udpv6_rcv,
1467 .err_handler = udpv6_err,
1468 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1469};
1470
1471/* ------------------------------------------------------------------------ */
1472#ifdef CONFIG_PROC_FS
1473int udp6_seq_show(struct seq_file *seq, void *v)
1474{
1475 if (v == SEQ_START_TOKEN) {
1476 seq_puts(seq, IPV6_SEQ_DGRAM_HEADER);
1477 } else {
1478 int bucket = ((struct udp_iter_state *)seq->private)->bucket;
1479 struct inet_sock *inet = inet_sk(v);
1480 __u16 srcp = ntohs(inet->inet_sport);
1481 __u16 destp = ntohs(inet->inet_dport);
1482 ip6_dgram_sock_seq_show(seq, v, srcp, destp, bucket);
1483 }
1484 return 0;
1485}
1486
1487static const struct file_operations udp6_afinfo_seq_fops = {
1488 .owner = THIS_MODULE,
1489 .open = udp_seq_open,
1490 .read = seq_read,
1491 .llseek = seq_lseek,
1492 .release = seq_release_net
1493};
1494
1495static struct udp_seq_afinfo udp6_seq_afinfo = {
1496 .name = "udp6",
1497 .family = AF_INET6,
1498 .udp_table = &udp_table,
1499 .seq_fops = &udp6_afinfo_seq_fops,
1500 .seq_ops = {
1501 .show = udp6_seq_show,
1502 },
1503};
1504
1505int __net_init udp6_proc_init(struct net *net)
1506{
1507 return udp_proc_register(net, &udp6_seq_afinfo);
1508}
1509
1510void udp6_proc_exit(struct net *net)
1511{
1512 udp_proc_unregister(net, &udp6_seq_afinfo);
1513}
1514#endif /* CONFIG_PROC_FS */
1515
1516void udp_v6_clear_sk(struct sock *sk, int size)
1517{
1518 struct inet_sock *inet = inet_sk(sk);
1519
1520 /* we do not want to clear pinet6 field, because of RCU lookups */
1521 sk_prot_clear_portaddr_nulls(sk, offsetof(struct inet_sock, pinet6));
1522
1523 size -= offsetof(struct inet_sock, pinet6) + sizeof(inet->pinet6);
1524 memset(&inet->pinet6 + 1, 0, size);
1525}
1526
1527/* ------------------------------------------------------------------------ */
1528
1529struct proto udpv6_prot = {
1530 .name = "UDPv6",
1531 .owner = THIS_MODULE,
1532 .close = udp_lib_close,
1533 .connect = ip6_datagram_connect,
1534 .disconnect = udp_disconnect,
1535 .ioctl = udp_ioctl,
1536 .destroy = udpv6_destroy_sock,
1537 .setsockopt = udpv6_setsockopt,
1538 .getsockopt = udpv6_getsockopt,
1539 .sendmsg = udpv6_sendmsg,
1540 .recvmsg = udpv6_recvmsg,
1541 .backlog_rcv = __udpv6_queue_rcv_skb,
1542 .release_cb = ip6_datagram_release_cb,
1543 .hash = udp_lib_hash,
1544 .unhash = udp_lib_unhash,
1545 .rehash = udp_v6_rehash,
1546 .get_port = udp_v6_get_port,
1547 .memory_allocated = &udp_memory_allocated,
1548 .sysctl_mem = sysctl_udp_mem,
1549 .sysctl_wmem = &sysctl_udp_wmem_min,
1550 .sysctl_rmem = &sysctl_udp_rmem_min,
1551 .obj_size = sizeof(struct udp6_sock),
1552 .slab_flags = SLAB_DESTROY_BY_RCU,
1553 .h.udp_table = &udp_table,
1554#ifdef CONFIG_COMPAT
1555 .compat_setsockopt = compat_udpv6_setsockopt,
1556 .compat_getsockopt = compat_udpv6_getsockopt,
1557#endif
1558 .clear_sk = udp_v6_clear_sk,
1559};
1560
1561static struct inet_protosw udpv6_protosw = {
1562 .type = SOCK_DGRAM,
1563 .protocol = IPPROTO_UDP,
1564 .prot = &udpv6_prot,
1565 .ops = &inet6_dgram_ops,
1566 .flags = INET_PROTOSW_PERMANENT,
1567};
1568
1569int __init udpv6_init(void)
1570{
1571 int ret;
1572
1573 ret = inet6_add_protocol(&udpv6_protocol, IPPROTO_UDP);
1574 if (ret)
1575 goto out;
1576
1577 ret = inet6_register_protosw(&udpv6_protosw);
1578 if (ret)
1579 goto out_udpv6_protocol;
1580out:
1581 return ret;
1582
1583out_udpv6_protocol:
1584 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1585 goto out;
1586}
1587
1588void udpv6_exit(void)
1589{
1590 inet6_unregister_protosw(&udpv6_protosw);
1591 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1592}
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/inet6_hashtables.h>
50#include <net/busy_poll.h>
51#include <net/sock_reuseport.h>
52
53#include <linux/proc_fs.h>
54#include <linux/seq_file.h>
55#include <trace/events/skb.h>
56#include "udp_impl.h"
57
58static u32 udp6_ehashfn(const struct net *net,
59 const struct in6_addr *laddr,
60 const u16 lport,
61 const struct in6_addr *faddr,
62 const __be16 fport)
63{
64 static u32 udp6_ehash_secret __read_mostly;
65 static u32 udp_ipv6_hash_secret __read_mostly;
66
67 u32 lhash, fhash;
68
69 net_get_random_once(&udp6_ehash_secret,
70 sizeof(udp6_ehash_secret));
71 net_get_random_once(&udp_ipv6_hash_secret,
72 sizeof(udp_ipv6_hash_secret));
73
74 lhash = (__force u32)laddr->s6_addr32[3];
75 fhash = __ipv6_addr_jhash(faddr, udp_ipv6_hash_secret);
76
77 return __inet6_ehashfn(lhash, lport, fhash, fport,
78 udp_ipv6_hash_secret + net_hash_mix(net));
79}
80
81static u32 udp6_portaddr_hash(const struct net *net,
82 const struct in6_addr *addr6,
83 unsigned int port)
84{
85 unsigned int hash, mix = net_hash_mix(net);
86
87 if (ipv6_addr_any(addr6))
88 hash = jhash_1word(0, mix);
89 else if (ipv6_addr_v4mapped(addr6))
90 hash = jhash_1word((__force u32)addr6->s6_addr32[3], mix);
91 else
92 hash = jhash2((__force u32 *)addr6->s6_addr32, 4, mix);
93
94 return hash ^ port;
95}
96
97int udp_v6_get_port(struct sock *sk, unsigned short snum)
98{
99 unsigned int hash2_nulladdr =
100 udp6_portaddr_hash(sock_net(sk), &in6addr_any, snum);
101 unsigned int hash2_partial =
102 udp6_portaddr_hash(sock_net(sk), &sk->sk_v6_rcv_saddr, 0);
103
104 /* precompute partial secondary hash */
105 udp_sk(sk)->udp_portaddr_hash = hash2_partial;
106 return udp_lib_get_port(sk, snum, ipv6_rcv_saddr_equal, hash2_nulladdr);
107}
108
109static void udp_v6_rehash(struct sock *sk)
110{
111 u16 new_hash = udp6_portaddr_hash(sock_net(sk),
112 &sk->sk_v6_rcv_saddr,
113 inet_sk(sk)->inet_num);
114
115 udp_lib_rehash(sk, new_hash);
116}
117
118static int compute_score(struct sock *sk, struct net *net,
119 const struct in6_addr *saddr, __be16 sport,
120 const struct in6_addr *daddr, unsigned short hnum,
121 int dif)
122{
123 int score;
124 struct inet_sock *inet;
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 score = 0;
132 inet = inet_sk(sk);
133
134 if (inet->inet_dport) {
135 if (inet->inet_dport != sport)
136 return -1;
137 score++;
138 }
139
140 if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr)) {
141 if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
142 return -1;
143 score++;
144 }
145
146 if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
147 if (!ipv6_addr_equal(&sk->sk_v6_daddr, saddr))
148 return -1;
149 score++;
150 }
151
152 if (sk->sk_bound_dev_if) {
153 if (sk->sk_bound_dev_if != dif)
154 return -1;
155 score++;
156 }
157
158 if (sk->sk_incoming_cpu == raw_smp_processor_id())
159 score++;
160
161 return score;
162}
163
164/* called with rcu_read_lock() */
165static struct sock *udp6_lib_lookup2(struct net *net,
166 const struct in6_addr *saddr, __be16 sport,
167 const struct in6_addr *daddr, unsigned int hnum, int dif,
168 struct udp_hslot *hslot2,
169 struct sk_buff *skb)
170{
171 struct sock *sk, *result;
172 int score, badness, matches = 0, reuseport = 0;
173 u32 hash = 0;
174
175 result = NULL;
176 badness = -1;
177 udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) {
178 score = compute_score(sk, net, saddr, sport,
179 daddr, hnum, dif);
180 if (score > badness) {
181 reuseport = sk->sk_reuseport;
182 if (reuseport) {
183 hash = udp6_ehashfn(net, daddr, hnum,
184 saddr, sport);
185
186 result = reuseport_select_sock(sk, hash, skb,
187 sizeof(struct udphdr));
188 if (result)
189 return result;
190 matches = 1;
191 }
192 result = sk;
193 badness = score;
194 } else if (score == badness && reuseport) {
195 matches++;
196 if (reciprocal_scale(hash, matches) == 0)
197 result = sk;
198 hash = next_pseudo_random32(hash);
199 }
200 }
201 return result;
202}
203
204/* rcu_read_lock() must be held */
205struct sock *__udp6_lib_lookup(struct net *net,
206 const struct in6_addr *saddr, __be16 sport,
207 const struct in6_addr *daddr, __be16 dport,
208 int dif, struct udp_table *udptable,
209 struct sk_buff *skb)
210{
211 struct sock *sk, *result;
212 unsigned short hnum = ntohs(dport);
213 unsigned int hash2, slot2, slot = udp_hashfn(net, hnum, udptable->mask);
214 struct udp_hslot *hslot2, *hslot = &udptable->hash[slot];
215 int score, badness, matches = 0, reuseport = 0;
216 u32 hash = 0;
217
218 if (hslot->count > 10) {
219 hash2 = udp6_portaddr_hash(net, daddr, hnum);
220 slot2 = hash2 & udptable->mask;
221 hslot2 = &udptable->hash2[slot2];
222 if (hslot->count < hslot2->count)
223 goto begin;
224
225 result = udp6_lib_lookup2(net, saddr, sport,
226 daddr, hnum, dif,
227 hslot2, skb);
228 if (!result) {
229 unsigned int old_slot2 = slot2;
230 hash2 = udp6_portaddr_hash(net, &in6addr_any, hnum);
231 slot2 = hash2 & udptable->mask;
232 /* avoid searching the same slot again. */
233 if (unlikely(slot2 == old_slot2))
234 return result;
235
236 hslot2 = &udptable->hash2[slot2];
237 if (hslot->count < hslot2->count)
238 goto begin;
239
240 result = udp6_lib_lookup2(net, saddr, sport,
241 daddr, hnum, dif,
242 hslot2, skb);
243 }
244 return result;
245 }
246begin:
247 result = NULL;
248 badness = -1;
249 sk_for_each_rcu(sk, &hslot->head) {
250 score = compute_score(sk, net, saddr, sport, daddr, hnum, dif);
251 if (score > badness) {
252 reuseport = sk->sk_reuseport;
253 if (reuseport) {
254 hash = udp6_ehashfn(net, daddr, hnum,
255 saddr, sport);
256 result = reuseport_select_sock(sk, hash, skb,
257 sizeof(struct udphdr));
258 if (result)
259 return result;
260 matches = 1;
261 }
262 result = sk;
263 badness = score;
264 } else if (score == badness && reuseport) {
265 matches++;
266 if (reciprocal_scale(hash, matches) == 0)
267 result = sk;
268 hash = next_pseudo_random32(hash);
269 }
270 }
271 return result;
272}
273EXPORT_SYMBOL_GPL(__udp6_lib_lookup);
274
275static struct sock *__udp6_lib_lookup_skb(struct sk_buff *skb,
276 __be16 sport, __be16 dport,
277 struct udp_table *udptable)
278{
279 const struct ipv6hdr *iph = ipv6_hdr(skb);
280 struct sock *sk;
281
282 sk = skb_steal_sock(skb);
283 if (unlikely(sk))
284 return sk;
285 return __udp6_lib_lookup(dev_net(skb->dev), &iph->saddr, sport,
286 &iph->daddr, dport, inet6_iif(skb),
287 udptable, skb);
288}
289
290struct sock *udp6_lib_lookup_skb(struct sk_buff *skb,
291 __be16 sport, __be16 dport)
292{
293 const struct ipv6hdr *iph = ipv6_hdr(skb);
294
295 return __udp6_lib_lookup(dev_net(skb->dev), &iph->saddr, sport,
296 &iph->daddr, dport, inet6_iif(skb),
297 &udp_table, skb);
298}
299EXPORT_SYMBOL_GPL(udp6_lib_lookup_skb);
300
301/* Must be called under rcu_read_lock().
302 * Does increment socket refcount.
303 */
304#if IS_ENABLED(CONFIG_NETFILTER_XT_MATCH_SOCKET) || \
305 IS_ENABLED(CONFIG_NETFILTER_XT_TARGET_TPROXY) || \
306 IS_ENABLED(CONFIG_NF_SOCKET_IPV6)
307struct sock *udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport,
308 const struct in6_addr *daddr, __be16 dport, int dif)
309{
310 struct sock *sk;
311
312 sk = __udp6_lib_lookup(net, saddr, sport, daddr, dport,
313 dif, &udp_table, NULL);
314 if (sk && !atomic_inc_not_zero(&sk->sk_refcnt))
315 sk = NULL;
316 return sk;
317}
318EXPORT_SYMBOL_GPL(udp6_lib_lookup);
319#endif
320
321/*
322 * This should be easy, if there is something there we
323 * return it, otherwise we block.
324 */
325
326int udpv6_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
327 int noblock, int flags, int *addr_len)
328{
329 struct ipv6_pinfo *np = inet6_sk(sk);
330 struct inet_sock *inet = inet_sk(sk);
331 struct sk_buff *skb;
332 unsigned int ulen, copied;
333 int peeked, peeking, off;
334 int err;
335 int is_udplite = IS_UDPLITE(sk);
336 bool checksum_valid = false;
337 int is_udp4;
338
339 if (flags & MSG_ERRQUEUE)
340 return ipv6_recv_error(sk, msg, len, addr_len);
341
342 if (np->rxpmtu && np->rxopt.bits.rxpmtu)
343 return ipv6_recv_rxpmtu(sk, msg, len, addr_len);
344
345try_again:
346 peeking = off = sk_peek_offset(sk, flags);
347 skb = __skb_recv_udp(sk, flags, noblock, &peeked, &off, &err);
348 if (!skb)
349 return err;
350
351 ulen = skb->len;
352 copied = len;
353 if (copied > ulen - off)
354 copied = ulen - off;
355 else if (copied < ulen)
356 msg->msg_flags |= MSG_TRUNC;
357
358 is_udp4 = (skb->protocol == htons(ETH_P_IP));
359
360 /*
361 * If checksum is needed at all, try to do it while copying the
362 * data. If the data is truncated, or if we only want a partial
363 * coverage checksum (UDP-Lite), do it before the copy.
364 */
365
366 if (copied < ulen || peeking ||
367 (is_udplite && UDP_SKB_CB(skb)->partial_cov)) {
368 checksum_valid = !udp_lib_checksum_complete(skb);
369 if (!checksum_valid)
370 goto csum_copy_err;
371 }
372
373 if (checksum_valid || skb_csum_unnecessary(skb))
374 err = skb_copy_datagram_msg(skb, off, msg, copied);
375 else {
376 err = skb_copy_and_csum_datagram_msg(skb, off, msg);
377 if (err == -EINVAL)
378 goto csum_copy_err;
379 }
380 if (unlikely(err)) {
381 if (!peeked) {
382 atomic_inc(&sk->sk_drops);
383 if (is_udp4)
384 UDP_INC_STATS(sock_net(sk), UDP_MIB_INERRORS,
385 is_udplite);
386 else
387 UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS,
388 is_udplite);
389 }
390 kfree_skb(skb);
391 return err;
392 }
393 if (!peeked) {
394 if (is_udp4)
395 UDP_INC_STATS(sock_net(sk), UDP_MIB_INDATAGRAMS,
396 is_udplite);
397 else
398 UDP6_INC_STATS(sock_net(sk), UDP_MIB_INDATAGRAMS,
399 is_udplite);
400 }
401
402 sock_recv_ts_and_drops(msg, sk, skb);
403
404 /* Copy the address. */
405 if (msg->msg_name) {
406 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
407 sin6->sin6_family = AF_INET6;
408 sin6->sin6_port = udp_hdr(skb)->source;
409 sin6->sin6_flowinfo = 0;
410
411 if (is_udp4) {
412 ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
413 &sin6->sin6_addr);
414 sin6->sin6_scope_id = 0;
415 } else {
416 sin6->sin6_addr = ipv6_hdr(skb)->saddr;
417 sin6->sin6_scope_id =
418 ipv6_iface_scope_id(&sin6->sin6_addr,
419 inet6_iif(skb));
420 }
421 *addr_len = sizeof(*sin6);
422 }
423
424 if (np->rxopt.all)
425 ip6_datagram_recv_common_ctl(sk, msg, skb);
426
427 if (is_udp4) {
428 if (inet->cmsg_flags)
429 ip_cmsg_recv_offset(msg, sk, skb,
430 sizeof(struct udphdr), off);
431 } else {
432 if (np->rxopt.all)
433 ip6_datagram_recv_specific_ctl(sk, msg, skb);
434 }
435
436 err = copied;
437 if (flags & MSG_TRUNC)
438 err = ulen;
439
440 skb_consume_udp(sk, skb, peeking ? -err : err);
441 return err;
442
443csum_copy_err:
444 if (!__sk_queue_drop_skb(sk, skb, flags, udp_skb_destructor)) {
445 if (is_udp4) {
446 UDP_INC_STATS(sock_net(sk),
447 UDP_MIB_CSUMERRORS, is_udplite);
448 UDP_INC_STATS(sock_net(sk),
449 UDP_MIB_INERRORS, is_udplite);
450 } else {
451 UDP6_INC_STATS(sock_net(sk),
452 UDP_MIB_CSUMERRORS, is_udplite);
453 UDP6_INC_STATS(sock_net(sk),
454 UDP_MIB_INERRORS, is_udplite);
455 }
456 }
457 kfree_skb(skb);
458
459 /* starting over for a new packet, but check if we need to yield */
460 cond_resched();
461 msg->msg_flags &= ~MSG_TRUNC;
462 goto try_again;
463}
464
465void __udp6_lib_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
466 u8 type, u8 code, int offset, __be32 info,
467 struct udp_table *udptable)
468{
469 struct ipv6_pinfo *np;
470 const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data;
471 const struct in6_addr *saddr = &hdr->saddr;
472 const struct in6_addr *daddr = &hdr->daddr;
473 struct udphdr *uh = (struct udphdr *)(skb->data+offset);
474 struct sock *sk;
475 int harderr;
476 int err;
477 struct net *net = dev_net(skb->dev);
478
479 sk = __udp6_lib_lookup(net, daddr, uh->dest, saddr, uh->source,
480 inet6_iif(skb), udptable, skb);
481 if (!sk) {
482 __ICMP6_INC_STATS(net, __in6_dev_get(skb->dev),
483 ICMP6_MIB_INERRORS);
484 return;
485 }
486
487 harderr = icmpv6_err_convert(type, code, &err);
488 np = inet6_sk(sk);
489
490 if (type == ICMPV6_PKT_TOOBIG) {
491 if (!ip6_sk_accept_pmtu(sk))
492 goto out;
493 ip6_sk_update_pmtu(skb, sk, info);
494 if (np->pmtudisc != IPV6_PMTUDISC_DONT)
495 harderr = 1;
496 }
497 if (type == NDISC_REDIRECT) {
498 ip6_sk_redirect(skb, sk);
499 goto out;
500 }
501
502 if (!np->recverr) {
503 if (!harderr || sk->sk_state != TCP_ESTABLISHED)
504 goto out;
505 } else {
506 ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1));
507 }
508
509 sk->sk_err = err;
510 sk->sk_error_report(sk);
511out:
512 return;
513}
514
515int __udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
516{
517 int rc;
518
519 if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
520 sock_rps_save_rxhash(sk, skb);
521 sk_mark_napi_id(sk, skb);
522 sk_incoming_cpu_update(sk);
523 } else {
524 sk_mark_napi_id_once(sk, skb);
525 }
526
527 rc = __udp_enqueue_schedule_skb(sk, skb);
528 if (rc < 0) {
529 int is_udplite = IS_UDPLITE(sk);
530
531 /* Note that an ENOMEM error is charged twice */
532 if (rc == -ENOMEM)
533 UDP6_INC_STATS(sock_net(sk),
534 UDP_MIB_RCVBUFERRORS, is_udplite);
535 UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
536 kfree_skb(skb);
537 return -1;
538 }
539
540 return 0;
541}
542
543static __inline__ void udpv6_err(struct sk_buff *skb,
544 struct inet6_skb_parm *opt, u8 type,
545 u8 code, int offset, __be32 info)
546{
547 __udp6_lib_err(skb, opt, type, code, offset, info, &udp_table);
548}
549
550static struct static_key udpv6_encap_needed __read_mostly;
551void udpv6_encap_enable(void)
552{
553 if (!static_key_enabled(&udpv6_encap_needed))
554 static_key_slow_inc(&udpv6_encap_needed);
555}
556EXPORT_SYMBOL(udpv6_encap_enable);
557
558int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
559{
560 struct udp_sock *up = udp_sk(sk);
561 int is_udplite = IS_UDPLITE(sk);
562
563 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
564 goto drop;
565
566 if (static_key_false(&udpv6_encap_needed) && up->encap_type) {
567 int (*encap_rcv)(struct sock *sk, struct sk_buff *skb);
568
569 /*
570 * This is an encapsulation socket so pass the skb to
571 * the socket's udp_encap_rcv() hook. Otherwise, just
572 * fall through and pass this up the UDP socket.
573 * up->encap_rcv() returns the following value:
574 * =0 if skb was successfully passed to the encap
575 * handler or was discarded by it.
576 * >0 if skb should be passed on to UDP.
577 * <0 if skb should be resubmitted as proto -N
578 */
579
580 /* if we're overly short, let UDP handle it */
581 encap_rcv = ACCESS_ONCE(up->encap_rcv);
582 if (encap_rcv) {
583 int ret;
584
585 /* Verify checksum before giving to encap */
586 if (udp_lib_checksum_complete(skb))
587 goto csum_error;
588
589 ret = encap_rcv(sk, skb);
590 if (ret <= 0) {
591 __UDP_INC_STATS(sock_net(sk),
592 UDP_MIB_INDATAGRAMS,
593 is_udplite);
594 return -ret;
595 }
596 }
597
598 /* FALLTHROUGH -- it's a UDP Packet */
599 }
600
601 /*
602 * UDP-Lite specific tests, ignored on UDP sockets (see net/ipv4/udp.c).
603 */
604 if ((is_udplite & UDPLITE_RECV_CC) && UDP_SKB_CB(skb)->partial_cov) {
605
606 if (up->pcrlen == 0) { /* full coverage was set */
607 net_dbg_ratelimited("UDPLITE6: partial coverage %d while full coverage %d requested\n",
608 UDP_SKB_CB(skb)->cscov, skb->len);
609 goto drop;
610 }
611 if (UDP_SKB_CB(skb)->cscov < up->pcrlen) {
612 net_dbg_ratelimited("UDPLITE6: coverage %d too small, need min %d\n",
613 UDP_SKB_CB(skb)->cscov, up->pcrlen);
614 goto drop;
615 }
616 }
617
618 if (rcu_access_pointer(sk->sk_filter) &&
619 udp_lib_checksum_complete(skb))
620 goto csum_error;
621
622 if (sk_filter_trim_cap(sk, skb, sizeof(struct udphdr)))
623 goto drop;
624
625 udp_csum_pull_header(skb);
626
627 skb_dst_drop(skb);
628
629 return __udpv6_queue_rcv_skb(sk, skb);
630
631csum_error:
632 __UDP6_INC_STATS(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite);
633drop:
634 __UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
635 atomic_inc(&sk->sk_drops);
636 kfree_skb(skb);
637 return -1;
638}
639
640static bool __udp_v6_is_mcast_sock(struct net *net, struct sock *sk,
641 __be16 loc_port, const struct in6_addr *loc_addr,
642 __be16 rmt_port, const struct in6_addr *rmt_addr,
643 int dif, unsigned short hnum)
644{
645 struct inet_sock *inet = inet_sk(sk);
646
647 if (!net_eq(sock_net(sk), net))
648 return false;
649
650 if (udp_sk(sk)->udp_port_hash != hnum ||
651 sk->sk_family != PF_INET6 ||
652 (inet->inet_dport && inet->inet_dport != rmt_port) ||
653 (!ipv6_addr_any(&sk->sk_v6_daddr) &&
654 !ipv6_addr_equal(&sk->sk_v6_daddr, rmt_addr)) ||
655 (sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif) ||
656 (!ipv6_addr_any(&sk->sk_v6_rcv_saddr) &&
657 !ipv6_addr_equal(&sk->sk_v6_rcv_saddr, loc_addr)))
658 return false;
659 if (!inet6_mc_check(sk, loc_addr, rmt_addr))
660 return false;
661 return true;
662}
663
664static void udp6_csum_zero_error(struct sk_buff *skb)
665{
666 /* RFC 2460 section 8.1 says that we SHOULD log
667 * this error. Well, it is reasonable.
668 */
669 net_dbg_ratelimited("IPv6: udp checksum is 0 for [%pI6c]:%u->[%pI6c]:%u\n",
670 &ipv6_hdr(skb)->saddr, ntohs(udp_hdr(skb)->source),
671 &ipv6_hdr(skb)->daddr, ntohs(udp_hdr(skb)->dest));
672}
673
674/*
675 * Note: called only from the BH handler context,
676 * so we don't need to lock the hashes.
677 */
678static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
679 const struct in6_addr *saddr, const struct in6_addr *daddr,
680 struct udp_table *udptable, int proto)
681{
682 struct sock *sk, *first = NULL;
683 const struct udphdr *uh = udp_hdr(skb);
684 unsigned short hnum = ntohs(uh->dest);
685 struct udp_hslot *hslot = udp_hashslot(udptable, net, hnum);
686 unsigned int offset = offsetof(typeof(*sk), sk_node);
687 unsigned int hash2 = 0, hash2_any = 0, use_hash2 = (hslot->count > 10);
688 int dif = inet6_iif(skb);
689 struct hlist_node *node;
690 struct sk_buff *nskb;
691
692 if (use_hash2) {
693 hash2_any = udp6_portaddr_hash(net, &in6addr_any, hnum) &
694 udptable->mask;
695 hash2 = udp6_portaddr_hash(net, daddr, hnum) & udptable->mask;
696start_lookup:
697 hslot = &udptable->hash2[hash2];
698 offset = offsetof(typeof(*sk), __sk_common.skc_portaddr_node);
699 }
700
701 sk_for_each_entry_offset_rcu(sk, node, &hslot->head, offset) {
702 if (!__udp_v6_is_mcast_sock(net, sk, uh->dest, daddr,
703 uh->source, saddr, dif, hnum))
704 continue;
705 /* If zero checksum and no_check is not on for
706 * the socket then skip it.
707 */
708 if (!uh->check && !udp_sk(sk)->no_check6_rx)
709 continue;
710 if (!first) {
711 first = sk;
712 continue;
713 }
714 nskb = skb_clone(skb, GFP_ATOMIC);
715 if (unlikely(!nskb)) {
716 atomic_inc(&sk->sk_drops);
717 __UDP6_INC_STATS(net, UDP_MIB_RCVBUFERRORS,
718 IS_UDPLITE(sk));
719 __UDP6_INC_STATS(net, UDP_MIB_INERRORS,
720 IS_UDPLITE(sk));
721 continue;
722 }
723
724 if (udpv6_queue_rcv_skb(sk, nskb) > 0)
725 consume_skb(nskb);
726 }
727
728 /* Also lookup *:port if we are using hash2 and haven't done so yet. */
729 if (use_hash2 && hash2 != hash2_any) {
730 hash2 = hash2_any;
731 goto start_lookup;
732 }
733
734 if (first) {
735 if (udpv6_queue_rcv_skb(first, skb) > 0)
736 consume_skb(skb);
737 } else {
738 kfree_skb(skb);
739 __UDP6_INC_STATS(net, UDP_MIB_IGNOREDMULTI,
740 proto == IPPROTO_UDPLITE);
741 }
742 return 0;
743}
744
745int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
746 int proto)
747{
748 const struct in6_addr *saddr, *daddr;
749 struct net *net = dev_net(skb->dev);
750 struct udphdr *uh;
751 struct sock *sk;
752 u32 ulen = 0;
753
754 if (!pskb_may_pull(skb, sizeof(struct udphdr)))
755 goto discard;
756
757 saddr = &ipv6_hdr(skb)->saddr;
758 daddr = &ipv6_hdr(skb)->daddr;
759 uh = udp_hdr(skb);
760
761 ulen = ntohs(uh->len);
762 if (ulen > skb->len)
763 goto short_packet;
764
765 if (proto == IPPROTO_UDP) {
766 /* UDP validates ulen. */
767
768 /* Check for jumbo payload */
769 if (ulen == 0)
770 ulen = skb->len;
771
772 if (ulen < sizeof(*uh))
773 goto short_packet;
774
775 if (ulen < skb->len) {
776 if (pskb_trim_rcsum(skb, ulen))
777 goto short_packet;
778 saddr = &ipv6_hdr(skb)->saddr;
779 daddr = &ipv6_hdr(skb)->daddr;
780 uh = udp_hdr(skb);
781 }
782 }
783
784 if (udp6_csum_init(skb, uh, proto))
785 goto csum_error;
786
787 /*
788 * Multicast receive code
789 */
790 if (ipv6_addr_is_multicast(daddr))
791 return __udp6_lib_mcast_deliver(net, skb,
792 saddr, daddr, udptable, proto);
793
794 /* Unicast */
795
796 /*
797 * check socket cache ... must talk to Alan about his plans
798 * for sock caches... i'll skip this for now.
799 */
800 sk = __udp6_lib_lookup_skb(skb, uh->source, uh->dest, udptable);
801 if (sk) {
802 int ret;
803
804 if (!uh->check && !udp_sk(sk)->no_check6_rx) {
805 udp6_csum_zero_error(skb);
806 goto csum_error;
807 }
808
809 if (inet_get_convert_csum(sk) && uh->check && !IS_UDPLITE(sk))
810 skb_checksum_try_convert(skb, IPPROTO_UDP, uh->check,
811 ip6_compute_pseudo);
812
813 ret = udpv6_queue_rcv_skb(sk, skb);
814
815 /* a return value > 0 means to resubmit the input */
816 if (ret > 0)
817 return ret;
818
819 return 0;
820 }
821
822 if (!uh->check) {
823 udp6_csum_zero_error(skb);
824 goto csum_error;
825 }
826
827 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
828 goto discard;
829
830 if (udp_lib_checksum_complete(skb))
831 goto csum_error;
832
833 __UDP6_INC_STATS(net, UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE);
834 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
835
836 kfree_skb(skb);
837 return 0;
838
839short_packet:
840 net_dbg_ratelimited("UDP%sv6: short packet: From [%pI6c]:%u %d/%d to [%pI6c]:%u\n",
841 proto == IPPROTO_UDPLITE ? "-Lite" : "",
842 saddr, ntohs(uh->source),
843 ulen, skb->len,
844 daddr, ntohs(uh->dest));
845 goto discard;
846csum_error:
847 __UDP6_INC_STATS(net, UDP_MIB_CSUMERRORS, proto == IPPROTO_UDPLITE);
848discard:
849 __UDP6_INC_STATS(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE);
850 kfree_skb(skb);
851 return 0;
852}
853
854static __inline__ int udpv6_rcv(struct sk_buff *skb)
855{
856 return __udp6_lib_rcv(skb, &udp_table, IPPROTO_UDP);
857}
858
859/*
860 * Throw away all pending data and cancel the corking. Socket is locked.
861 */
862static void udp_v6_flush_pending_frames(struct sock *sk)
863{
864 struct udp_sock *up = udp_sk(sk);
865
866 if (up->pending == AF_INET)
867 udp_flush_pending_frames(sk);
868 else if (up->pending) {
869 up->len = 0;
870 up->pending = 0;
871 ip6_flush_pending_frames(sk);
872 }
873}
874
875/**
876 * udp6_hwcsum_outgoing - handle outgoing HW checksumming
877 * @sk: socket we are sending on
878 * @skb: sk_buff containing the filled-in UDP header
879 * (checksum field must be zeroed out)
880 */
881static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb,
882 const struct in6_addr *saddr,
883 const struct in6_addr *daddr, int len)
884{
885 unsigned int offset;
886 struct udphdr *uh = udp_hdr(skb);
887 struct sk_buff *frags = skb_shinfo(skb)->frag_list;
888 __wsum csum = 0;
889
890 if (!frags) {
891 /* Only one fragment on the socket. */
892 skb->csum_start = skb_transport_header(skb) - skb->head;
893 skb->csum_offset = offsetof(struct udphdr, check);
894 uh->check = ~csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 0);
895 } else {
896 /*
897 * HW-checksum won't work as there are two or more
898 * fragments on the socket so that all csums of sk_buffs
899 * should be together
900 */
901 offset = skb_transport_offset(skb);
902 skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
903
904 skb->ip_summed = CHECKSUM_NONE;
905
906 do {
907 csum = csum_add(csum, frags->csum);
908 } while ((frags = frags->next));
909
910 uh->check = csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP,
911 csum);
912 if (uh->check == 0)
913 uh->check = CSUM_MANGLED_0;
914 }
915}
916
917/*
918 * Sending
919 */
920
921static int udp_v6_send_skb(struct sk_buff *skb, struct flowi6 *fl6)
922{
923 struct sock *sk = skb->sk;
924 struct udphdr *uh;
925 int err = 0;
926 int is_udplite = IS_UDPLITE(sk);
927 __wsum csum = 0;
928 int offset = skb_transport_offset(skb);
929 int len = skb->len - offset;
930
931 /*
932 * Create a UDP header
933 */
934 uh = udp_hdr(skb);
935 uh->source = fl6->fl6_sport;
936 uh->dest = fl6->fl6_dport;
937 uh->len = htons(len);
938 uh->check = 0;
939
940 if (is_udplite)
941 csum = udplite_csum(skb);
942 else if (udp_sk(sk)->no_check6_tx) { /* UDP csum disabled */
943 skb->ip_summed = CHECKSUM_NONE;
944 goto send;
945 } else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */
946 udp6_hwcsum_outgoing(sk, skb, &fl6->saddr, &fl6->daddr, len);
947 goto send;
948 } else
949 csum = udp_csum(skb);
950
951 /* add protocol-dependent pseudo-header */
952 uh->check = csum_ipv6_magic(&fl6->saddr, &fl6->daddr,
953 len, fl6->flowi6_proto, csum);
954 if (uh->check == 0)
955 uh->check = CSUM_MANGLED_0;
956
957send:
958 err = ip6_send_skb(skb);
959 if (err) {
960 if (err == -ENOBUFS && !inet6_sk(sk)->recverr) {
961 UDP6_INC_STATS(sock_net(sk),
962 UDP_MIB_SNDBUFERRORS, is_udplite);
963 err = 0;
964 }
965 } else {
966 UDP6_INC_STATS(sock_net(sk),
967 UDP_MIB_OUTDATAGRAMS, is_udplite);
968 }
969 return err;
970}
971
972static int udp_v6_push_pending_frames(struct sock *sk)
973{
974 struct sk_buff *skb;
975 struct udp_sock *up = udp_sk(sk);
976 struct flowi6 fl6;
977 int err = 0;
978
979 if (up->pending == AF_INET)
980 return udp_push_pending_frames(sk);
981
982 /* ip6_finish_skb will release the cork, so make a copy of
983 * fl6 here.
984 */
985 fl6 = inet_sk(sk)->cork.fl.u.ip6;
986
987 skb = ip6_finish_skb(sk);
988 if (!skb)
989 goto out;
990
991 err = udp_v6_send_skb(skb, &fl6);
992
993out:
994 up->len = 0;
995 up->pending = 0;
996 return err;
997}
998
999int udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
1000{
1001 struct ipv6_txoptions opt_space;
1002 struct udp_sock *up = udp_sk(sk);
1003 struct inet_sock *inet = inet_sk(sk);
1004 struct ipv6_pinfo *np = inet6_sk(sk);
1005 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
1006 struct in6_addr *daddr, *final_p, final;
1007 struct ipv6_txoptions *opt = NULL;
1008 struct ipv6_txoptions *opt_to_free = NULL;
1009 struct ip6_flowlabel *flowlabel = NULL;
1010 struct flowi6 fl6;
1011 struct dst_entry *dst;
1012 struct ipcm6_cookie ipc6;
1013 int addr_len = msg->msg_namelen;
1014 int ulen = len;
1015 int corkreq = up->corkflag || msg->msg_flags&MSG_MORE;
1016 int err;
1017 int connected = 0;
1018 int is_udplite = IS_UDPLITE(sk);
1019 int (*getfrag)(void *, char *, int, int, int, struct sk_buff *);
1020 struct sockcm_cookie sockc;
1021
1022 ipc6.hlimit = -1;
1023 ipc6.tclass = -1;
1024 ipc6.dontfrag = -1;
1025 sockc.tsflags = sk->sk_tsflags;
1026
1027 /* destination address check */
1028 if (sin6) {
1029 if (addr_len < offsetof(struct sockaddr, sa_data))
1030 return -EINVAL;
1031
1032 switch (sin6->sin6_family) {
1033 case AF_INET6:
1034 if (addr_len < SIN6_LEN_RFC2133)
1035 return -EINVAL;
1036 daddr = &sin6->sin6_addr;
1037 if (ipv6_addr_any(daddr) &&
1038 ipv6_addr_v4mapped(&np->saddr))
1039 ipv6_addr_set_v4mapped(htonl(INADDR_LOOPBACK),
1040 daddr);
1041 break;
1042 case AF_INET:
1043 goto do_udp_sendmsg;
1044 case AF_UNSPEC:
1045 msg->msg_name = sin6 = NULL;
1046 msg->msg_namelen = addr_len = 0;
1047 daddr = NULL;
1048 break;
1049 default:
1050 return -EINVAL;
1051 }
1052 } else if (!up->pending) {
1053 if (sk->sk_state != TCP_ESTABLISHED)
1054 return -EDESTADDRREQ;
1055 daddr = &sk->sk_v6_daddr;
1056 } else
1057 daddr = NULL;
1058
1059 if (daddr) {
1060 if (ipv6_addr_v4mapped(daddr)) {
1061 struct sockaddr_in sin;
1062 sin.sin_family = AF_INET;
1063 sin.sin_port = sin6 ? sin6->sin6_port : inet->inet_dport;
1064 sin.sin_addr.s_addr = daddr->s6_addr32[3];
1065 msg->msg_name = &sin;
1066 msg->msg_namelen = sizeof(sin);
1067do_udp_sendmsg:
1068 if (__ipv6_only_sock(sk))
1069 return -ENETUNREACH;
1070 return udp_sendmsg(sk, msg, len);
1071 }
1072 }
1073
1074 if (up->pending == AF_INET)
1075 return udp_sendmsg(sk, msg, len);
1076
1077 /* Rough check on arithmetic overflow,
1078 better check is made in ip6_append_data().
1079 */
1080 if (len > INT_MAX - sizeof(struct udphdr))
1081 return -EMSGSIZE;
1082
1083 getfrag = is_udplite ? udplite_getfrag : ip_generic_getfrag;
1084 if (up->pending) {
1085 /*
1086 * There are pending frames.
1087 * The socket lock must be held while it's corked.
1088 */
1089 lock_sock(sk);
1090 if (likely(up->pending)) {
1091 if (unlikely(up->pending != AF_INET6)) {
1092 release_sock(sk);
1093 return -EAFNOSUPPORT;
1094 }
1095 dst = NULL;
1096 goto do_append_data;
1097 }
1098 release_sock(sk);
1099 }
1100 ulen += sizeof(struct udphdr);
1101
1102 memset(&fl6, 0, sizeof(fl6));
1103
1104 if (sin6) {
1105 if (sin6->sin6_port == 0)
1106 return -EINVAL;
1107
1108 fl6.fl6_dport = sin6->sin6_port;
1109 daddr = &sin6->sin6_addr;
1110
1111 if (np->sndflow) {
1112 fl6.flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK;
1113 if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) {
1114 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1115 if (!flowlabel)
1116 return -EINVAL;
1117 }
1118 }
1119
1120 /*
1121 * Otherwise it will be difficult to maintain
1122 * sk->sk_dst_cache.
1123 */
1124 if (sk->sk_state == TCP_ESTABLISHED &&
1125 ipv6_addr_equal(daddr, &sk->sk_v6_daddr))
1126 daddr = &sk->sk_v6_daddr;
1127
1128 if (addr_len >= sizeof(struct sockaddr_in6) &&
1129 sin6->sin6_scope_id &&
1130 __ipv6_addr_needs_scope_id(__ipv6_addr_type(daddr)))
1131 fl6.flowi6_oif = sin6->sin6_scope_id;
1132 } else {
1133 if (sk->sk_state != TCP_ESTABLISHED)
1134 return -EDESTADDRREQ;
1135
1136 fl6.fl6_dport = inet->inet_dport;
1137 daddr = &sk->sk_v6_daddr;
1138 fl6.flowlabel = np->flow_label;
1139 connected = 1;
1140 }
1141
1142 if (!fl6.flowi6_oif)
1143 fl6.flowi6_oif = sk->sk_bound_dev_if;
1144
1145 if (!fl6.flowi6_oif)
1146 fl6.flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;
1147
1148 fl6.flowi6_mark = sk->sk_mark;
1149 fl6.flowi6_uid = sk->sk_uid;
1150
1151 if (msg->msg_controllen) {
1152 opt = &opt_space;
1153 memset(opt, 0, sizeof(struct ipv6_txoptions));
1154 opt->tot_len = sizeof(*opt);
1155 ipc6.opt = opt;
1156
1157 err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, &fl6, &ipc6, &sockc);
1158 if (err < 0) {
1159 fl6_sock_release(flowlabel);
1160 return err;
1161 }
1162 if ((fl6.flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) {
1163 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1164 if (!flowlabel)
1165 return -EINVAL;
1166 }
1167 if (!(opt->opt_nflen|opt->opt_flen))
1168 opt = NULL;
1169 connected = 0;
1170 }
1171 if (!opt) {
1172 opt = txopt_get(np);
1173 opt_to_free = opt;
1174 }
1175 if (flowlabel)
1176 opt = fl6_merge_options(&opt_space, flowlabel, opt);
1177 opt = ipv6_fixup_options(&opt_space, opt);
1178 ipc6.opt = opt;
1179
1180 fl6.flowi6_proto = sk->sk_protocol;
1181 if (!ipv6_addr_any(daddr))
1182 fl6.daddr = *daddr;
1183 else
1184 fl6.daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */
1185 if (ipv6_addr_any(&fl6.saddr) && !ipv6_addr_any(&np->saddr))
1186 fl6.saddr = np->saddr;
1187 fl6.fl6_sport = inet->inet_sport;
1188
1189 final_p = fl6_update_dst(&fl6, opt, &final);
1190 if (final_p)
1191 connected = 0;
1192
1193 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr)) {
1194 fl6.flowi6_oif = np->mcast_oif;
1195 connected = 0;
1196 } else if (!fl6.flowi6_oif)
1197 fl6.flowi6_oif = np->ucast_oif;
1198
1199 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
1200
1201 if (ipc6.tclass < 0)
1202 ipc6.tclass = np->tclass;
1203
1204 fl6.flowlabel = ip6_make_flowinfo(ipc6.tclass, fl6.flowlabel);
1205
1206 dst = ip6_sk_dst_lookup_flow(sk, &fl6, final_p);
1207 if (IS_ERR(dst)) {
1208 err = PTR_ERR(dst);
1209 dst = NULL;
1210 goto out;
1211 }
1212
1213 if (ipc6.hlimit < 0)
1214 ipc6.hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
1215
1216 if (msg->msg_flags&MSG_CONFIRM)
1217 goto do_confirm;
1218back_from_confirm:
1219
1220 /* Lockless fast path for the non-corking case */
1221 if (!corkreq) {
1222 struct sk_buff *skb;
1223
1224 skb = ip6_make_skb(sk, getfrag, msg, ulen,
1225 sizeof(struct udphdr), &ipc6,
1226 &fl6, (struct rt6_info *)dst,
1227 msg->msg_flags, &sockc);
1228 err = PTR_ERR(skb);
1229 if (!IS_ERR_OR_NULL(skb))
1230 err = udp_v6_send_skb(skb, &fl6);
1231 goto release_dst;
1232 }
1233
1234 lock_sock(sk);
1235 if (unlikely(up->pending)) {
1236 /* The socket is already corked while preparing it. */
1237 /* ... which is an evident application bug. --ANK */
1238 release_sock(sk);
1239
1240 net_dbg_ratelimited("udp cork app bug 2\n");
1241 err = -EINVAL;
1242 goto out;
1243 }
1244
1245 up->pending = AF_INET6;
1246
1247do_append_data:
1248 if (ipc6.dontfrag < 0)
1249 ipc6.dontfrag = np->dontfrag;
1250 up->len += ulen;
1251 err = ip6_append_data(sk, getfrag, msg, ulen, sizeof(struct udphdr),
1252 &ipc6, &fl6, (struct rt6_info *)dst,
1253 corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags, &sockc);
1254 if (err)
1255 udp_v6_flush_pending_frames(sk);
1256 else if (!corkreq)
1257 err = udp_v6_push_pending_frames(sk);
1258 else if (unlikely(skb_queue_empty(&sk->sk_write_queue)))
1259 up->pending = 0;
1260
1261 if (err > 0)
1262 err = np->recverr ? net_xmit_errno(err) : 0;
1263 release_sock(sk);
1264
1265release_dst:
1266 if (dst) {
1267 if (connected) {
1268 ip6_dst_store(sk, dst,
1269 ipv6_addr_equal(&fl6.daddr, &sk->sk_v6_daddr) ?
1270 &sk->sk_v6_daddr : NULL,
1271#ifdef CONFIG_IPV6_SUBTREES
1272 ipv6_addr_equal(&fl6.saddr, &np->saddr) ?
1273 &np->saddr :
1274#endif
1275 NULL);
1276 } else {
1277 dst_release(dst);
1278 }
1279 dst = NULL;
1280 }
1281
1282out:
1283 dst_release(dst);
1284 fl6_sock_release(flowlabel);
1285 txopt_put(opt_to_free);
1286 if (!err)
1287 return len;
1288 /*
1289 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space. Reporting
1290 * ENOBUFS might not be good (it's not tunable per se), but otherwise
1291 * we don't have a good statistic (IpOutDiscards but it can be too many
1292 * things). We could add another new stat but at least for now that
1293 * seems like overkill.
1294 */
1295 if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) {
1296 UDP6_INC_STATS(sock_net(sk),
1297 UDP_MIB_SNDBUFERRORS, is_udplite);
1298 }
1299 return err;
1300
1301do_confirm:
1302 dst_confirm(dst);
1303 if (!(msg->msg_flags&MSG_PROBE) || len)
1304 goto back_from_confirm;
1305 err = 0;
1306 goto out;
1307}
1308
1309void udpv6_destroy_sock(struct sock *sk)
1310{
1311 struct udp_sock *up = udp_sk(sk);
1312 lock_sock(sk);
1313 udp_v6_flush_pending_frames(sk);
1314 release_sock(sk);
1315
1316 if (static_key_false(&udpv6_encap_needed) && up->encap_type) {
1317 void (*encap_destroy)(struct sock *sk);
1318 encap_destroy = ACCESS_ONCE(up->encap_destroy);
1319 if (encap_destroy)
1320 encap_destroy(sk);
1321 }
1322
1323 inet6_destroy_sock(sk);
1324}
1325
1326/*
1327 * Socket option code for UDP
1328 */
1329int udpv6_setsockopt(struct sock *sk, int level, int optname,
1330 char __user *optval, unsigned int optlen)
1331{
1332 if (level == SOL_UDP || level == SOL_UDPLITE)
1333 return udp_lib_setsockopt(sk, level, optname, optval, optlen,
1334 udp_v6_push_pending_frames);
1335 return ipv6_setsockopt(sk, level, optname, optval, optlen);
1336}
1337
1338#ifdef CONFIG_COMPAT
1339int compat_udpv6_setsockopt(struct sock *sk, int level, int optname,
1340 char __user *optval, unsigned int optlen)
1341{
1342 if (level == SOL_UDP || level == SOL_UDPLITE)
1343 return udp_lib_setsockopt(sk, level, optname, optval, optlen,
1344 udp_v6_push_pending_frames);
1345 return compat_ipv6_setsockopt(sk, level, optname, optval, optlen);
1346}
1347#endif
1348
1349int udpv6_getsockopt(struct sock *sk, int level, int optname,
1350 char __user *optval, int __user *optlen)
1351{
1352 if (level == SOL_UDP || level == SOL_UDPLITE)
1353 return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1354 return ipv6_getsockopt(sk, level, optname, optval, optlen);
1355}
1356
1357#ifdef CONFIG_COMPAT
1358int compat_udpv6_getsockopt(struct sock *sk, int level, int optname,
1359 char __user *optval, int __user *optlen)
1360{
1361 if (level == SOL_UDP || level == SOL_UDPLITE)
1362 return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1363 return compat_ipv6_getsockopt(sk, level, optname, optval, optlen);
1364}
1365#endif
1366
1367static const struct inet6_protocol udpv6_protocol = {
1368 .handler = udpv6_rcv,
1369 .err_handler = udpv6_err,
1370 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1371};
1372
1373/* ------------------------------------------------------------------------ */
1374#ifdef CONFIG_PROC_FS
1375int udp6_seq_show(struct seq_file *seq, void *v)
1376{
1377 if (v == SEQ_START_TOKEN) {
1378 seq_puts(seq, IPV6_SEQ_DGRAM_HEADER);
1379 } else {
1380 int bucket = ((struct udp_iter_state *)seq->private)->bucket;
1381 struct inet_sock *inet = inet_sk(v);
1382 __u16 srcp = ntohs(inet->inet_sport);
1383 __u16 destp = ntohs(inet->inet_dport);
1384 ip6_dgram_sock_seq_show(seq, v, srcp, destp, bucket);
1385 }
1386 return 0;
1387}
1388
1389static const struct file_operations udp6_afinfo_seq_fops = {
1390 .owner = THIS_MODULE,
1391 .open = udp_seq_open,
1392 .read = seq_read,
1393 .llseek = seq_lseek,
1394 .release = seq_release_net
1395};
1396
1397static struct udp_seq_afinfo udp6_seq_afinfo = {
1398 .name = "udp6",
1399 .family = AF_INET6,
1400 .udp_table = &udp_table,
1401 .seq_fops = &udp6_afinfo_seq_fops,
1402 .seq_ops = {
1403 .show = udp6_seq_show,
1404 },
1405};
1406
1407int __net_init udp6_proc_init(struct net *net)
1408{
1409 return udp_proc_register(net, &udp6_seq_afinfo);
1410}
1411
1412void udp6_proc_exit(struct net *net)
1413{
1414 udp_proc_unregister(net, &udp6_seq_afinfo);
1415}
1416#endif /* CONFIG_PROC_FS */
1417
1418/* ------------------------------------------------------------------------ */
1419
1420struct proto udpv6_prot = {
1421 .name = "UDPv6",
1422 .owner = THIS_MODULE,
1423 .close = udp_lib_close,
1424 .connect = ip6_datagram_connect,
1425 .disconnect = udp_disconnect,
1426 .ioctl = udp_ioctl,
1427 .init = udp_init_sock,
1428 .destroy = udpv6_destroy_sock,
1429 .setsockopt = udpv6_setsockopt,
1430 .getsockopt = udpv6_getsockopt,
1431 .sendmsg = udpv6_sendmsg,
1432 .recvmsg = udpv6_recvmsg,
1433 .release_cb = ip6_datagram_release_cb,
1434 .hash = udp_lib_hash,
1435 .unhash = udp_lib_unhash,
1436 .rehash = udp_v6_rehash,
1437 .get_port = udp_v6_get_port,
1438 .memory_allocated = &udp_memory_allocated,
1439 .sysctl_mem = sysctl_udp_mem,
1440 .sysctl_wmem = &sysctl_udp_wmem_min,
1441 .sysctl_rmem = &sysctl_udp_rmem_min,
1442 .obj_size = sizeof(struct udp6_sock),
1443 .h.udp_table = &udp_table,
1444#ifdef CONFIG_COMPAT
1445 .compat_setsockopt = compat_udpv6_setsockopt,
1446 .compat_getsockopt = compat_udpv6_getsockopt,
1447#endif
1448 .diag_destroy = udp_abort,
1449};
1450
1451static struct inet_protosw udpv6_protosw = {
1452 .type = SOCK_DGRAM,
1453 .protocol = IPPROTO_UDP,
1454 .prot = &udpv6_prot,
1455 .ops = &inet6_dgram_ops,
1456 .flags = INET_PROTOSW_PERMANENT,
1457};
1458
1459int __init udpv6_init(void)
1460{
1461 int ret;
1462
1463 ret = inet6_add_protocol(&udpv6_protocol, IPPROTO_UDP);
1464 if (ret)
1465 goto out;
1466
1467 ret = inet6_register_protosw(&udpv6_protosw);
1468 if (ret)
1469 goto out_udpv6_protocol;
1470out:
1471 return ret;
1472
1473out_udpv6_protocol:
1474 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1475 goto out;
1476}
1477
1478void udpv6_exit(void)
1479{
1480 inet6_unregister_protosw(&udpv6_protosw);
1481 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1482}