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Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
[mirror_ubuntu-artful-kernel.git] / net / ipv6 / udp.c
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
59 static 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
69 static 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
92 static u32 udp6_portaddr_hash(const struct net *net,
93 const struct in6_addr *addr6,
94 unsigned int port)
95 {
96 unsigned int hash, mix = net_hash_mix(net);
97
98 if (ipv6_addr_any(addr6))
99 hash = jhash_1word(0, mix);
100 else if (ipv6_addr_v4mapped(addr6))
101 hash = jhash_1word((__force u32)addr6->s6_addr32[3], mix);
102 else
103 hash = jhash2((__force u32 *)addr6->s6_addr32, 4, mix);
104
105 return hash ^ port;
106 }
107
108 int udp_v6_get_port(struct sock *sk, unsigned short snum)
109 {
110 unsigned int hash2_nulladdr =
111 udp6_portaddr_hash(sock_net(sk), &in6addr_any, snum);
112 unsigned int hash2_partial =
113 udp6_portaddr_hash(sock_net(sk), &sk->sk_v6_rcv_saddr, 0);
114
115 /* precompute partial secondary hash */
116 udp_sk(sk)->udp_portaddr_hash = hash2_partial;
117 return udp_lib_get_port(sk, snum, hash2_nulladdr);
118 }
119
120 static void udp_v6_rehash(struct sock *sk)
121 {
122 u16 new_hash = udp6_portaddr_hash(sock_net(sk),
123 &sk->sk_v6_rcv_saddr,
124 inet_sk(sk)->inet_num);
125
126 udp_lib_rehash(sk, new_hash);
127 }
128
129 static int compute_score(struct sock *sk, struct net *net,
130 const struct in6_addr *saddr, __be16 sport,
131 const struct in6_addr *daddr, unsigned short hnum,
132 int dif, bool exact_dif)
133 {
134 int score;
135 struct inet_sock *inet;
136
137 if (!net_eq(sock_net(sk), net) ||
138 udp_sk(sk)->udp_port_hash != hnum ||
139 sk->sk_family != PF_INET6)
140 return -1;
141
142 score = 0;
143 inet = inet_sk(sk);
144
145 if (inet->inet_dport) {
146 if (inet->inet_dport != sport)
147 return -1;
148 score++;
149 }
150
151 if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr)) {
152 if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
153 return -1;
154 score++;
155 }
156
157 if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
158 if (!ipv6_addr_equal(&sk->sk_v6_daddr, saddr))
159 return -1;
160 score++;
161 }
162
163 if (sk->sk_bound_dev_if || exact_dif) {
164 if (sk->sk_bound_dev_if != dif)
165 return -1;
166 score++;
167 }
168
169 if (sk->sk_incoming_cpu == raw_smp_processor_id())
170 score++;
171
172 return score;
173 }
174
175 /* called with rcu_read_lock() */
176 static struct sock *udp6_lib_lookup2(struct net *net,
177 const struct in6_addr *saddr, __be16 sport,
178 const struct in6_addr *daddr, unsigned int hnum, int dif,
179 bool exact_dif, struct udp_hslot *hslot2,
180 struct sk_buff *skb)
181 {
182 struct sock *sk, *result;
183 int score, badness, matches = 0, reuseport = 0;
184 u32 hash = 0;
185
186 result = NULL;
187 badness = -1;
188 udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) {
189 score = compute_score(sk, net, saddr, sport,
190 daddr, hnum, dif, exact_dif);
191 if (score > badness) {
192 reuseport = sk->sk_reuseport;
193 if (reuseport) {
194 hash = udp6_ehashfn(net, daddr, hnum,
195 saddr, sport);
196
197 result = reuseport_select_sock(sk, hash, skb,
198 sizeof(struct udphdr));
199 if (result)
200 return result;
201 matches = 1;
202 }
203 result = sk;
204 badness = score;
205 } else if (score == badness && reuseport) {
206 matches++;
207 if (reciprocal_scale(hash, matches) == 0)
208 result = sk;
209 hash = next_pseudo_random32(hash);
210 }
211 }
212 return result;
213 }
214
215 /* rcu_read_lock() must be held */
216 struct sock *__udp6_lib_lookup(struct net *net,
217 const struct in6_addr *saddr, __be16 sport,
218 const struct in6_addr *daddr, __be16 dport,
219 int dif, struct udp_table *udptable,
220 struct sk_buff *skb)
221 {
222 struct sock *sk, *result;
223 unsigned short hnum = ntohs(dport);
224 unsigned int hash2, slot2, slot = udp_hashfn(net, hnum, udptable->mask);
225 struct udp_hslot *hslot2, *hslot = &udptable->hash[slot];
226 bool exact_dif = udp6_lib_exact_dif_match(net, skb);
227 int score, badness, matches = 0, reuseport = 0;
228 u32 hash = 0;
229
230 if (hslot->count > 10) {
231 hash2 = udp6_portaddr_hash(net, daddr, hnum);
232 slot2 = hash2 & udptable->mask;
233 hslot2 = &udptable->hash2[slot2];
234 if (hslot->count < hslot2->count)
235 goto begin;
236
237 result = udp6_lib_lookup2(net, saddr, sport,
238 daddr, hnum, dif, exact_dif,
239 hslot2, skb);
240 if (!result) {
241 unsigned int old_slot2 = slot2;
242 hash2 = udp6_portaddr_hash(net, &in6addr_any, hnum);
243 slot2 = hash2 & udptable->mask;
244 /* avoid searching the same slot again. */
245 if (unlikely(slot2 == old_slot2))
246 return result;
247
248 hslot2 = &udptable->hash2[slot2];
249 if (hslot->count < hslot2->count)
250 goto begin;
251
252 result = udp6_lib_lookup2(net, saddr, sport,
253 daddr, hnum, dif,
254 exact_dif, hslot2,
255 skb);
256 }
257 return result;
258 }
259 begin:
260 result = NULL;
261 badness = -1;
262 sk_for_each_rcu(sk, &hslot->head) {
263 score = compute_score(sk, net, saddr, sport, daddr, hnum, dif,
264 exact_dif);
265 if (score > badness) {
266 reuseport = sk->sk_reuseport;
267 if (reuseport) {
268 hash = udp6_ehashfn(net, daddr, hnum,
269 saddr, sport);
270 result = reuseport_select_sock(sk, hash, skb,
271 sizeof(struct udphdr));
272 if (result)
273 return result;
274 matches = 1;
275 }
276 result = sk;
277 badness = score;
278 } else if (score == badness && reuseport) {
279 matches++;
280 if (reciprocal_scale(hash, matches) == 0)
281 result = sk;
282 hash = next_pseudo_random32(hash);
283 }
284 }
285 return result;
286 }
287 EXPORT_SYMBOL_GPL(__udp6_lib_lookup);
288
289 static struct sock *__udp6_lib_lookup_skb(struct sk_buff *skb,
290 __be16 sport, __be16 dport,
291 struct udp_table *udptable)
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 udptable, skb);
298 }
299
300 struct sock *udp6_lib_lookup_skb(struct sk_buff *skb,
301 __be16 sport, __be16 dport)
302 {
303 const struct ipv6hdr *iph = ipv6_hdr(skb);
304
305 return __udp6_lib_lookup(dev_net(skb->dev), &iph->saddr, sport,
306 &iph->daddr, dport, inet6_iif(skb),
307 &udp_table, skb);
308 }
309 EXPORT_SYMBOL_GPL(udp6_lib_lookup_skb);
310
311 /* Must be called under rcu_read_lock().
312 * Does increment socket refcount.
313 */
314 #if IS_ENABLED(CONFIG_NETFILTER_XT_MATCH_SOCKET) || \
315 IS_ENABLED(CONFIG_NETFILTER_XT_TARGET_TPROXY) || \
316 IS_ENABLED(CONFIG_NF_SOCKET_IPV6)
317 struct sock *udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport,
318 const struct in6_addr *daddr, __be16 dport, int dif)
319 {
320 struct sock *sk;
321
322 sk = __udp6_lib_lookup(net, saddr, sport, daddr, dport,
323 dif, &udp_table, NULL);
324 if (sk && !refcount_inc_not_zero(&sk->sk_refcnt))
325 sk = NULL;
326 return sk;
327 }
328 EXPORT_SYMBOL_GPL(udp6_lib_lookup);
329 #endif
330
331 /* do not use the scratch area len for jumbogram: their length execeeds the
332 * scratch area space; note that the IP6CB flags is still in the first
333 * cacheline, so checking for jumbograms is cheap
334 */
335 static int udp6_skb_len(struct sk_buff *skb)
336 {
337 return unlikely(inet6_is_jumbogram(skb)) ? skb->len : udp_skb_len(skb);
338 }
339
340 /*
341 * This should be easy, if there is something there we
342 * return it, otherwise we block.
343 */
344
345 int udpv6_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
346 int noblock, int flags, int *addr_len)
347 {
348 struct ipv6_pinfo *np = inet6_sk(sk);
349 struct inet_sock *inet = inet_sk(sk);
350 struct sk_buff *skb;
351 unsigned int ulen, copied;
352 int peeked, peeking, off;
353 int err;
354 int is_udplite = IS_UDPLITE(sk);
355 bool checksum_valid = false;
356 int is_udp4;
357
358 if (flags & MSG_ERRQUEUE)
359 return ipv6_recv_error(sk, msg, len, addr_len);
360
361 if (np->rxpmtu && np->rxopt.bits.rxpmtu)
362 return ipv6_recv_rxpmtu(sk, msg, len, addr_len);
363
364 try_again:
365 peeking = off = sk_peek_offset(sk, flags);
366 skb = __skb_recv_udp(sk, flags, noblock, &peeked, &off, &err);
367 if (!skb)
368 return err;
369
370 ulen = udp6_skb_len(skb);
371 copied = len;
372 if (copied > ulen - off)
373 copied = ulen - off;
374 else if (copied < ulen)
375 msg->msg_flags |= MSG_TRUNC;
376
377 is_udp4 = (skb->protocol == htons(ETH_P_IP));
378
379 /*
380 * If checksum is needed at all, try to do it while copying the
381 * data. If the data is truncated, or if we only want a partial
382 * coverage checksum (UDP-Lite), do it before the copy.
383 */
384
385 if (copied < ulen || peeking ||
386 (is_udplite && UDP_SKB_CB(skb)->partial_cov)) {
387 checksum_valid = udp_skb_csum_unnecessary(skb) ||
388 !__udp_lib_checksum_complete(skb);
389 if (!checksum_valid)
390 goto csum_copy_err;
391 }
392
393 if (checksum_valid || udp_skb_csum_unnecessary(skb)) {
394 if (udp_skb_is_linear(skb))
395 err = copy_linear_skb(skb, copied, off, &msg->msg_iter);
396 else
397 err = skb_copy_datagram_msg(skb, off, msg, copied);
398 } else {
399 err = skb_copy_and_csum_datagram_msg(skb, off, msg);
400 if (err == -EINVAL)
401 goto csum_copy_err;
402 }
403 if (unlikely(err)) {
404 if (!peeked) {
405 atomic_inc(&sk->sk_drops);
406 if (is_udp4)
407 UDP_INC_STATS(sock_net(sk), UDP_MIB_INERRORS,
408 is_udplite);
409 else
410 UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS,
411 is_udplite);
412 }
413 kfree_skb(skb);
414 return err;
415 }
416 if (!peeked) {
417 if (is_udp4)
418 UDP_INC_STATS(sock_net(sk), UDP_MIB_INDATAGRAMS,
419 is_udplite);
420 else
421 UDP6_INC_STATS(sock_net(sk), UDP_MIB_INDATAGRAMS,
422 is_udplite);
423 }
424
425 sock_recv_ts_and_drops(msg, sk, skb);
426
427 /* Copy the address. */
428 if (msg->msg_name) {
429 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
430 sin6->sin6_family = AF_INET6;
431 sin6->sin6_port = udp_hdr(skb)->source;
432 sin6->sin6_flowinfo = 0;
433
434 if (is_udp4) {
435 ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
436 &sin6->sin6_addr);
437 sin6->sin6_scope_id = 0;
438 } else {
439 sin6->sin6_addr = ipv6_hdr(skb)->saddr;
440 sin6->sin6_scope_id =
441 ipv6_iface_scope_id(&sin6->sin6_addr,
442 inet6_iif(skb));
443 }
444 *addr_len = sizeof(*sin6);
445 }
446
447 if (np->rxopt.all)
448 ip6_datagram_recv_common_ctl(sk, msg, skb);
449
450 if (is_udp4) {
451 if (inet->cmsg_flags)
452 ip_cmsg_recv_offset(msg, sk, skb,
453 sizeof(struct udphdr), off);
454 } else {
455 if (np->rxopt.all)
456 ip6_datagram_recv_specific_ctl(sk, msg, skb);
457 }
458
459 err = copied;
460 if (flags & MSG_TRUNC)
461 err = ulen;
462
463 skb_consume_udp(sk, skb, peeking ? -err : err);
464 return err;
465
466 csum_copy_err:
467 if (!__sk_queue_drop_skb(sk, &udp_sk(sk)->reader_queue, skb, flags,
468 udp_skb_destructor)) {
469 if (is_udp4) {
470 UDP_INC_STATS(sock_net(sk),
471 UDP_MIB_CSUMERRORS, is_udplite);
472 UDP_INC_STATS(sock_net(sk),
473 UDP_MIB_INERRORS, is_udplite);
474 } else {
475 UDP6_INC_STATS(sock_net(sk),
476 UDP_MIB_CSUMERRORS, is_udplite);
477 UDP6_INC_STATS(sock_net(sk),
478 UDP_MIB_INERRORS, is_udplite);
479 }
480 }
481 kfree_skb(skb);
482
483 /* starting over for a new packet, but check if we need to yield */
484 cond_resched();
485 msg->msg_flags &= ~MSG_TRUNC;
486 goto try_again;
487 }
488
489 void __udp6_lib_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
490 u8 type, u8 code, int offset, __be32 info,
491 struct udp_table *udptable)
492 {
493 struct ipv6_pinfo *np;
494 const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data;
495 const struct in6_addr *saddr = &hdr->saddr;
496 const struct in6_addr *daddr = &hdr->daddr;
497 struct udphdr *uh = (struct udphdr *)(skb->data+offset);
498 struct sock *sk;
499 int harderr;
500 int err;
501 struct net *net = dev_net(skb->dev);
502
503 sk = __udp6_lib_lookup(net, daddr, uh->dest, saddr, uh->source,
504 inet6_iif(skb), udptable, skb);
505 if (!sk) {
506 __ICMP6_INC_STATS(net, __in6_dev_get(skb->dev),
507 ICMP6_MIB_INERRORS);
508 return;
509 }
510
511 harderr = icmpv6_err_convert(type, code, &err);
512 np = inet6_sk(sk);
513
514 if (type == ICMPV6_PKT_TOOBIG) {
515 if (!ip6_sk_accept_pmtu(sk))
516 goto out;
517 ip6_sk_update_pmtu(skb, sk, info);
518 if (np->pmtudisc != IPV6_PMTUDISC_DONT)
519 harderr = 1;
520 }
521 if (type == NDISC_REDIRECT) {
522 ip6_sk_redirect(skb, sk);
523 goto out;
524 }
525
526 if (!np->recverr) {
527 if (!harderr || sk->sk_state != TCP_ESTABLISHED)
528 goto out;
529 } else {
530 ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1));
531 }
532
533 sk->sk_err = err;
534 sk->sk_error_report(sk);
535 out:
536 return;
537 }
538
539 static int __udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
540 {
541 int rc;
542
543 if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
544 sock_rps_save_rxhash(sk, skb);
545 sk_mark_napi_id(sk, skb);
546 sk_incoming_cpu_update(sk);
547 } else {
548 sk_mark_napi_id_once(sk, skb);
549 }
550
551 rc = __udp_enqueue_schedule_skb(sk, skb);
552 if (rc < 0) {
553 int is_udplite = IS_UDPLITE(sk);
554
555 /* Note that an ENOMEM error is charged twice */
556 if (rc == -ENOMEM)
557 UDP6_INC_STATS(sock_net(sk),
558 UDP_MIB_RCVBUFERRORS, is_udplite);
559 UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
560 kfree_skb(skb);
561 return -1;
562 }
563
564 return 0;
565 }
566
567 static __inline__ void udpv6_err(struct sk_buff *skb,
568 struct inet6_skb_parm *opt, u8 type,
569 u8 code, int offset, __be32 info)
570 {
571 __udp6_lib_err(skb, opt, type, code, offset, info, &udp_table);
572 }
573
574 static struct static_key udpv6_encap_needed __read_mostly;
575 void udpv6_encap_enable(void)
576 {
577 if (!static_key_enabled(&udpv6_encap_needed))
578 static_key_slow_inc(&udpv6_encap_needed);
579 }
580 EXPORT_SYMBOL(udpv6_encap_enable);
581
582 static int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
583 {
584 struct udp_sock *up = udp_sk(sk);
585 int is_udplite = IS_UDPLITE(sk);
586
587 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
588 goto drop;
589
590 if (static_key_false(&udpv6_encap_needed) && up->encap_type) {
591 int (*encap_rcv)(struct sock *sk, struct sk_buff *skb);
592
593 /*
594 * This is an encapsulation socket so pass the skb to
595 * the socket's udp_encap_rcv() hook. Otherwise, just
596 * fall through and pass this up the UDP socket.
597 * up->encap_rcv() returns the following value:
598 * =0 if skb was successfully passed to the encap
599 * handler or was discarded by it.
600 * >0 if skb should be passed on to UDP.
601 * <0 if skb should be resubmitted as proto -N
602 */
603
604 /* if we're overly short, let UDP handle it */
605 encap_rcv = ACCESS_ONCE(up->encap_rcv);
606 if (encap_rcv) {
607 int ret;
608
609 /* Verify checksum before giving to encap */
610 if (udp_lib_checksum_complete(skb))
611 goto csum_error;
612
613 ret = encap_rcv(sk, skb);
614 if (ret <= 0) {
615 __UDP_INC_STATS(sock_net(sk),
616 UDP_MIB_INDATAGRAMS,
617 is_udplite);
618 return -ret;
619 }
620 }
621
622 /* FALLTHROUGH -- it's a UDP Packet */
623 }
624
625 /*
626 * UDP-Lite specific tests, ignored on UDP sockets (see net/ipv4/udp.c).
627 */
628 if ((is_udplite & UDPLITE_RECV_CC) && UDP_SKB_CB(skb)->partial_cov) {
629
630 if (up->pcrlen == 0) { /* full coverage was set */
631 net_dbg_ratelimited("UDPLITE6: partial coverage %d while full coverage %d requested\n",
632 UDP_SKB_CB(skb)->cscov, skb->len);
633 goto drop;
634 }
635 if (UDP_SKB_CB(skb)->cscov < up->pcrlen) {
636 net_dbg_ratelimited("UDPLITE6: coverage %d too small, need min %d\n",
637 UDP_SKB_CB(skb)->cscov, up->pcrlen);
638 goto drop;
639 }
640 }
641
642 prefetch(&sk->sk_rmem_alloc);
643 if (rcu_access_pointer(sk->sk_filter) &&
644 udp_lib_checksum_complete(skb))
645 goto csum_error;
646
647 if (sk_filter_trim_cap(sk, skb, sizeof(struct udphdr)))
648 goto drop;
649
650 udp_csum_pull_header(skb);
651
652 skb_dst_drop(skb);
653
654 return __udpv6_queue_rcv_skb(sk, skb);
655
656 csum_error:
657 __UDP6_INC_STATS(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite);
658 drop:
659 __UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
660 atomic_inc(&sk->sk_drops);
661 kfree_skb(skb);
662 return -1;
663 }
664
665 static bool __udp_v6_is_mcast_sock(struct net *net, struct sock *sk,
666 __be16 loc_port, const struct in6_addr *loc_addr,
667 __be16 rmt_port, const struct in6_addr *rmt_addr,
668 int dif, unsigned short hnum)
669 {
670 struct inet_sock *inet = inet_sk(sk);
671
672 if (!net_eq(sock_net(sk), net))
673 return false;
674
675 if (udp_sk(sk)->udp_port_hash != hnum ||
676 sk->sk_family != PF_INET6 ||
677 (inet->inet_dport && inet->inet_dport != rmt_port) ||
678 (!ipv6_addr_any(&sk->sk_v6_daddr) &&
679 !ipv6_addr_equal(&sk->sk_v6_daddr, rmt_addr)) ||
680 (sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif) ||
681 (!ipv6_addr_any(&sk->sk_v6_rcv_saddr) &&
682 !ipv6_addr_equal(&sk->sk_v6_rcv_saddr, loc_addr)))
683 return false;
684 if (!inet6_mc_check(sk, loc_addr, rmt_addr))
685 return false;
686 return true;
687 }
688
689 static void udp6_csum_zero_error(struct sk_buff *skb)
690 {
691 /* RFC 2460 section 8.1 says that we SHOULD log
692 * this error. Well, it is reasonable.
693 */
694 net_dbg_ratelimited("IPv6: udp checksum is 0 for [%pI6c]:%u->[%pI6c]:%u\n",
695 &ipv6_hdr(skb)->saddr, ntohs(udp_hdr(skb)->source),
696 &ipv6_hdr(skb)->daddr, ntohs(udp_hdr(skb)->dest));
697 }
698
699 /*
700 * Note: called only from the BH handler context,
701 * so we don't need to lock the hashes.
702 */
703 static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
704 const struct in6_addr *saddr, const struct in6_addr *daddr,
705 struct udp_table *udptable, int proto)
706 {
707 struct sock *sk, *first = NULL;
708 const struct udphdr *uh = udp_hdr(skb);
709 unsigned short hnum = ntohs(uh->dest);
710 struct udp_hslot *hslot = udp_hashslot(udptable, net, hnum);
711 unsigned int offset = offsetof(typeof(*sk), sk_node);
712 unsigned int hash2 = 0, hash2_any = 0, use_hash2 = (hslot->count > 10);
713 int dif = inet6_iif(skb);
714 struct hlist_node *node;
715 struct sk_buff *nskb;
716
717 if (use_hash2) {
718 hash2_any = udp6_portaddr_hash(net, &in6addr_any, hnum) &
719 udptable->mask;
720 hash2 = udp6_portaddr_hash(net, daddr, hnum) & udptable->mask;
721 start_lookup:
722 hslot = &udptable->hash2[hash2];
723 offset = offsetof(typeof(*sk), __sk_common.skc_portaddr_node);
724 }
725
726 sk_for_each_entry_offset_rcu(sk, node, &hslot->head, offset) {
727 if (!__udp_v6_is_mcast_sock(net, sk, uh->dest, daddr,
728 uh->source, saddr, dif, hnum))
729 continue;
730 /* If zero checksum and no_check is not on for
731 * the socket then skip it.
732 */
733 if (!uh->check && !udp_sk(sk)->no_check6_rx)
734 continue;
735 if (!first) {
736 first = sk;
737 continue;
738 }
739 nskb = skb_clone(skb, GFP_ATOMIC);
740 if (unlikely(!nskb)) {
741 atomic_inc(&sk->sk_drops);
742 __UDP6_INC_STATS(net, UDP_MIB_RCVBUFERRORS,
743 IS_UDPLITE(sk));
744 __UDP6_INC_STATS(net, UDP_MIB_INERRORS,
745 IS_UDPLITE(sk));
746 continue;
747 }
748
749 if (udpv6_queue_rcv_skb(sk, nskb) > 0)
750 consume_skb(nskb);
751 }
752
753 /* Also lookup *:port if we are using hash2 and haven't done so yet. */
754 if (use_hash2 && hash2 != hash2_any) {
755 hash2 = hash2_any;
756 goto start_lookup;
757 }
758
759 if (first) {
760 if (udpv6_queue_rcv_skb(first, skb) > 0)
761 consume_skb(skb);
762 } else {
763 kfree_skb(skb);
764 __UDP6_INC_STATS(net, UDP_MIB_IGNOREDMULTI,
765 proto == IPPROTO_UDPLITE);
766 }
767 return 0;
768 }
769
770 int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
771 int proto)
772 {
773 const struct in6_addr *saddr, *daddr;
774 struct net *net = dev_net(skb->dev);
775 struct udphdr *uh;
776 struct sock *sk;
777 u32 ulen = 0;
778
779 if (!pskb_may_pull(skb, sizeof(struct udphdr)))
780 goto discard;
781
782 saddr = &ipv6_hdr(skb)->saddr;
783 daddr = &ipv6_hdr(skb)->daddr;
784 uh = udp_hdr(skb);
785
786 ulen = ntohs(uh->len);
787 if (ulen > skb->len)
788 goto short_packet;
789
790 if (proto == IPPROTO_UDP) {
791 /* UDP validates ulen. */
792
793 /* Check for jumbo payload */
794 if (ulen == 0)
795 ulen = skb->len;
796
797 if (ulen < sizeof(*uh))
798 goto short_packet;
799
800 if (ulen < skb->len) {
801 if (pskb_trim_rcsum(skb, ulen))
802 goto short_packet;
803 saddr = &ipv6_hdr(skb)->saddr;
804 daddr = &ipv6_hdr(skb)->daddr;
805 uh = udp_hdr(skb);
806 }
807 }
808
809 if (udp6_csum_init(skb, uh, proto))
810 goto csum_error;
811
812 /* Check if the socket is already available, e.g. due to early demux */
813 sk = skb_steal_sock(skb);
814 if (sk) {
815 struct dst_entry *dst = skb_dst(skb);
816 int ret;
817
818 if (unlikely(sk->sk_rx_dst != dst))
819 udp_sk_rx_dst_set(sk, dst);
820
821 ret = udpv6_queue_rcv_skb(sk, skb);
822 sock_put(sk);
823
824 /* a return value > 0 means to resubmit the input */
825 if (ret > 0)
826 return ret;
827 return 0;
828 }
829
830 /*
831 * Multicast receive code
832 */
833 if (ipv6_addr_is_multicast(daddr))
834 return __udp6_lib_mcast_deliver(net, skb,
835 saddr, daddr, udptable, proto);
836
837 /* Unicast */
838 sk = __udp6_lib_lookup_skb(skb, uh->source, uh->dest, udptable);
839 if (sk) {
840 int ret;
841
842 if (!uh->check && !udp_sk(sk)->no_check6_rx) {
843 udp6_csum_zero_error(skb);
844 goto csum_error;
845 }
846
847 if (inet_get_convert_csum(sk) && uh->check && !IS_UDPLITE(sk))
848 skb_checksum_try_convert(skb, IPPROTO_UDP, uh->check,
849 ip6_compute_pseudo);
850
851 ret = udpv6_queue_rcv_skb(sk, skb);
852
853 /* a return value > 0 means to resubmit the input */
854 if (ret > 0)
855 return ret;
856
857 return 0;
858 }
859
860 if (!uh->check) {
861 udp6_csum_zero_error(skb);
862 goto csum_error;
863 }
864
865 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
866 goto discard;
867
868 if (udp_lib_checksum_complete(skb))
869 goto csum_error;
870
871 __UDP6_INC_STATS(net, UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE);
872 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
873
874 kfree_skb(skb);
875 return 0;
876
877 short_packet:
878 net_dbg_ratelimited("UDP%sv6: short packet: From [%pI6c]:%u %d/%d to [%pI6c]:%u\n",
879 proto == IPPROTO_UDPLITE ? "-Lite" : "",
880 saddr, ntohs(uh->source),
881 ulen, skb->len,
882 daddr, ntohs(uh->dest));
883 goto discard;
884 csum_error:
885 __UDP6_INC_STATS(net, UDP_MIB_CSUMERRORS, proto == IPPROTO_UDPLITE);
886 discard:
887 __UDP6_INC_STATS(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE);
888 kfree_skb(skb);
889 return 0;
890 }
891
892
893 static struct sock *__udp6_lib_demux_lookup(struct net *net,
894 __be16 loc_port, const struct in6_addr *loc_addr,
895 __be16 rmt_port, const struct in6_addr *rmt_addr,
896 int dif)
897 {
898 unsigned short hnum = ntohs(loc_port);
899 unsigned int hash2 = udp6_portaddr_hash(net, loc_addr, hnum);
900 unsigned int slot2 = hash2 & udp_table.mask;
901 struct udp_hslot *hslot2 = &udp_table.hash2[slot2];
902 const __portpair ports = INET_COMBINED_PORTS(rmt_port, hnum);
903 struct sock *sk;
904
905 udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) {
906 if (sk->sk_state == TCP_ESTABLISHED &&
907 INET6_MATCH(sk, net, rmt_addr, loc_addr, ports, dif))
908 return sk;
909 /* Only check first socket in chain */
910 break;
911 }
912 return NULL;
913 }
914
915 static void udp_v6_early_demux(struct sk_buff *skb)
916 {
917 struct net *net = dev_net(skb->dev);
918 const struct udphdr *uh;
919 struct sock *sk;
920 struct dst_entry *dst;
921 int dif = skb->dev->ifindex;
922
923 if (!pskb_may_pull(skb, skb_transport_offset(skb) +
924 sizeof(struct udphdr)))
925 return;
926
927 uh = udp_hdr(skb);
928
929 if (skb->pkt_type == PACKET_HOST)
930 sk = __udp6_lib_demux_lookup(net, uh->dest,
931 &ipv6_hdr(skb)->daddr,
932 uh->source, &ipv6_hdr(skb)->saddr,
933 dif);
934 else
935 return;
936
937 if (!sk || !refcount_inc_not_zero(&sk->sk_refcnt))
938 return;
939
940 skb->sk = sk;
941 skb->destructor = sock_efree;
942 dst = READ_ONCE(sk->sk_rx_dst);
943
944 if (dst)
945 dst = dst_check(dst, inet6_sk(sk)->rx_dst_cookie);
946 if (dst) {
947 /* set noref for now.
948 * any place which wants to hold dst has to call
949 * dst_hold_safe()
950 */
951 skb_dst_set_noref(skb, dst);
952 }
953 }
954
955 static __inline__ int udpv6_rcv(struct sk_buff *skb)
956 {
957 return __udp6_lib_rcv(skb, &udp_table, IPPROTO_UDP);
958 }
959
960 /*
961 * Throw away all pending data and cancel the corking. Socket is locked.
962 */
963 static void udp_v6_flush_pending_frames(struct sock *sk)
964 {
965 struct udp_sock *up = udp_sk(sk);
966
967 if (up->pending == AF_INET)
968 udp_flush_pending_frames(sk);
969 else if (up->pending) {
970 up->len = 0;
971 up->pending = 0;
972 ip6_flush_pending_frames(sk);
973 }
974 }
975
976 /**
977 * udp6_hwcsum_outgoing - handle outgoing HW checksumming
978 * @sk: socket we are sending on
979 * @skb: sk_buff containing the filled-in UDP header
980 * (checksum field must be zeroed out)
981 */
982 static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb,
983 const struct in6_addr *saddr,
984 const struct in6_addr *daddr, int len)
985 {
986 unsigned int offset;
987 struct udphdr *uh = udp_hdr(skb);
988 struct sk_buff *frags = skb_shinfo(skb)->frag_list;
989 __wsum csum = 0;
990
991 if (!frags) {
992 /* Only one fragment on the socket. */
993 skb->csum_start = skb_transport_header(skb) - skb->head;
994 skb->csum_offset = offsetof(struct udphdr, check);
995 uh->check = ~csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 0);
996 } else {
997 /*
998 * HW-checksum won't work as there are two or more
999 * fragments on the socket so that all csums of sk_buffs
1000 * should be together
1001 */
1002 offset = skb_transport_offset(skb);
1003 skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
1004
1005 skb->ip_summed = CHECKSUM_NONE;
1006
1007 do {
1008 csum = csum_add(csum, frags->csum);
1009 } while ((frags = frags->next));
1010
1011 uh->check = csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP,
1012 csum);
1013 if (uh->check == 0)
1014 uh->check = CSUM_MANGLED_0;
1015 }
1016 }
1017
1018 /*
1019 * Sending
1020 */
1021
1022 static int udp_v6_send_skb(struct sk_buff *skb, struct flowi6 *fl6)
1023 {
1024 struct sock *sk = skb->sk;
1025 struct udphdr *uh;
1026 int err = 0;
1027 int is_udplite = IS_UDPLITE(sk);
1028 __wsum csum = 0;
1029 int offset = skb_transport_offset(skb);
1030 int len = skb->len - offset;
1031
1032 /*
1033 * Create a UDP header
1034 */
1035 uh = udp_hdr(skb);
1036 uh->source = fl6->fl6_sport;
1037 uh->dest = fl6->fl6_dport;
1038 uh->len = htons(len);
1039 uh->check = 0;
1040
1041 if (is_udplite)
1042 csum = udplite_csum(skb);
1043 else if (udp_sk(sk)->no_check6_tx) { /* UDP csum disabled */
1044 skb->ip_summed = CHECKSUM_NONE;
1045 goto send;
1046 } else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */
1047 udp6_hwcsum_outgoing(sk, skb, &fl6->saddr, &fl6->daddr, len);
1048 goto send;
1049 } else
1050 csum = udp_csum(skb);
1051
1052 /* add protocol-dependent pseudo-header */
1053 uh->check = csum_ipv6_magic(&fl6->saddr, &fl6->daddr,
1054 len, fl6->flowi6_proto, csum);
1055 if (uh->check == 0)
1056 uh->check = CSUM_MANGLED_0;
1057
1058 send:
1059 err = ip6_send_skb(skb);
1060 if (err) {
1061 if (err == -ENOBUFS && !inet6_sk(sk)->recverr) {
1062 UDP6_INC_STATS(sock_net(sk),
1063 UDP_MIB_SNDBUFERRORS, is_udplite);
1064 err = 0;
1065 }
1066 } else {
1067 UDP6_INC_STATS(sock_net(sk),
1068 UDP_MIB_OUTDATAGRAMS, is_udplite);
1069 }
1070 return err;
1071 }
1072
1073 static int udp_v6_push_pending_frames(struct sock *sk)
1074 {
1075 struct sk_buff *skb;
1076 struct udp_sock *up = udp_sk(sk);
1077 struct flowi6 fl6;
1078 int err = 0;
1079
1080 if (up->pending == AF_INET)
1081 return udp_push_pending_frames(sk);
1082
1083 /* ip6_finish_skb will release the cork, so make a copy of
1084 * fl6 here.
1085 */
1086 fl6 = inet_sk(sk)->cork.fl.u.ip6;
1087
1088 skb = ip6_finish_skb(sk);
1089 if (!skb)
1090 goto out;
1091
1092 err = udp_v6_send_skb(skb, &fl6);
1093
1094 out:
1095 up->len = 0;
1096 up->pending = 0;
1097 return err;
1098 }
1099
1100 int udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
1101 {
1102 struct ipv6_txoptions opt_space;
1103 struct udp_sock *up = udp_sk(sk);
1104 struct inet_sock *inet = inet_sk(sk);
1105 struct ipv6_pinfo *np = inet6_sk(sk);
1106 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
1107 struct in6_addr *daddr, *final_p, final;
1108 struct ipv6_txoptions *opt = NULL;
1109 struct ipv6_txoptions *opt_to_free = NULL;
1110 struct ip6_flowlabel *flowlabel = NULL;
1111 struct flowi6 fl6;
1112 struct dst_entry *dst;
1113 struct ipcm6_cookie ipc6;
1114 int addr_len = msg->msg_namelen;
1115 int ulen = len;
1116 int corkreq = up->corkflag || msg->msg_flags&MSG_MORE;
1117 int err;
1118 int connected = 0;
1119 int is_udplite = IS_UDPLITE(sk);
1120 int (*getfrag)(void *, char *, int, int, int, struct sk_buff *);
1121 struct sockcm_cookie sockc;
1122
1123 ipc6.hlimit = -1;
1124 ipc6.tclass = -1;
1125 ipc6.dontfrag = -1;
1126 sockc.tsflags = sk->sk_tsflags;
1127
1128 /* destination address check */
1129 if (sin6) {
1130 if (addr_len < offsetof(struct sockaddr, sa_data))
1131 return -EINVAL;
1132
1133 switch (sin6->sin6_family) {
1134 case AF_INET6:
1135 if (addr_len < SIN6_LEN_RFC2133)
1136 return -EINVAL;
1137 daddr = &sin6->sin6_addr;
1138 if (ipv6_addr_any(daddr) &&
1139 ipv6_addr_v4mapped(&np->saddr))
1140 ipv6_addr_set_v4mapped(htonl(INADDR_LOOPBACK),
1141 daddr);
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);
1168 do_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 fl6.flowi6_uid = sk->sk_uid;
1251
1252 if (msg->msg_controllen) {
1253 opt = &opt_space;
1254 memset(opt, 0, sizeof(struct ipv6_txoptions));
1255 opt->tot_len = sizeof(*opt);
1256 ipc6.opt = opt;
1257
1258 err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, &fl6, &ipc6, &sockc);
1259 if (err < 0) {
1260 fl6_sock_release(flowlabel);
1261 return err;
1262 }
1263 if ((fl6.flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) {
1264 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1265 if (!flowlabel)
1266 return -EINVAL;
1267 }
1268 if (!(opt->opt_nflen|opt->opt_flen))
1269 opt = NULL;
1270 connected = 0;
1271 }
1272 if (!opt) {
1273 opt = txopt_get(np);
1274 opt_to_free = opt;
1275 }
1276 if (flowlabel)
1277 opt = fl6_merge_options(&opt_space, flowlabel, opt);
1278 opt = ipv6_fixup_options(&opt_space, opt);
1279 ipc6.opt = opt;
1280
1281 fl6.flowi6_proto = sk->sk_protocol;
1282 if (!ipv6_addr_any(daddr))
1283 fl6.daddr = *daddr;
1284 else
1285 fl6.daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */
1286 if (ipv6_addr_any(&fl6.saddr) && !ipv6_addr_any(&np->saddr))
1287 fl6.saddr = np->saddr;
1288 fl6.fl6_sport = inet->inet_sport;
1289
1290 final_p = fl6_update_dst(&fl6, opt, &final);
1291 if (final_p)
1292 connected = 0;
1293
1294 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr)) {
1295 fl6.flowi6_oif = np->mcast_oif;
1296 connected = 0;
1297 } else if (!fl6.flowi6_oif)
1298 fl6.flowi6_oif = np->ucast_oif;
1299
1300 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
1301
1302 if (ipc6.tclass < 0)
1303 ipc6.tclass = np->tclass;
1304
1305 fl6.flowlabel = ip6_make_flowinfo(ipc6.tclass, fl6.flowlabel);
1306
1307 dst = ip6_sk_dst_lookup_flow(sk, &fl6, final_p);
1308 if (IS_ERR(dst)) {
1309 err = PTR_ERR(dst);
1310 dst = NULL;
1311 goto out;
1312 }
1313
1314 if (ipc6.hlimit < 0)
1315 ipc6.hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
1316
1317 if (msg->msg_flags&MSG_CONFIRM)
1318 goto do_confirm;
1319 back_from_confirm:
1320
1321 /* Lockless fast path for the non-corking case */
1322 if (!corkreq) {
1323 struct sk_buff *skb;
1324
1325 skb = ip6_make_skb(sk, getfrag, msg, ulen,
1326 sizeof(struct udphdr), &ipc6,
1327 &fl6, (struct rt6_info *)dst,
1328 msg->msg_flags, &sockc);
1329 err = PTR_ERR(skb);
1330 if (!IS_ERR_OR_NULL(skb))
1331 err = udp_v6_send_skb(skb, &fl6);
1332 goto release_dst;
1333 }
1334
1335 lock_sock(sk);
1336 if (unlikely(up->pending)) {
1337 /* The socket is already corked while preparing it. */
1338 /* ... which is an evident application bug. --ANK */
1339 release_sock(sk);
1340
1341 net_dbg_ratelimited("udp cork app bug 2\n");
1342 err = -EINVAL;
1343 goto out;
1344 }
1345
1346 up->pending = AF_INET6;
1347
1348 do_append_data:
1349 if (ipc6.dontfrag < 0)
1350 ipc6.dontfrag = np->dontfrag;
1351 up->len += ulen;
1352 err = ip6_append_data(sk, getfrag, msg, ulen, sizeof(struct udphdr),
1353 &ipc6, &fl6, (struct rt6_info *)dst,
1354 corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags, &sockc);
1355 if (err)
1356 udp_v6_flush_pending_frames(sk);
1357 else if (!corkreq)
1358 err = udp_v6_push_pending_frames(sk);
1359 else if (unlikely(skb_queue_empty(&sk->sk_write_queue)))
1360 up->pending = 0;
1361
1362 if (err > 0)
1363 err = np->recverr ? net_xmit_errno(err) : 0;
1364 release_sock(sk);
1365
1366 release_dst:
1367 if (dst) {
1368 if (connected) {
1369 ip6_dst_store(sk, dst,
1370 ipv6_addr_equal(&fl6.daddr, &sk->sk_v6_daddr) ?
1371 &sk->sk_v6_daddr : NULL,
1372 #ifdef CONFIG_IPV6_SUBTREES
1373 ipv6_addr_equal(&fl6.saddr, &np->saddr) ?
1374 &np->saddr :
1375 #endif
1376 NULL);
1377 } else {
1378 dst_release(dst);
1379 }
1380 dst = NULL;
1381 }
1382
1383 out:
1384 dst_release(dst);
1385 fl6_sock_release(flowlabel);
1386 txopt_put(opt_to_free);
1387 if (!err)
1388 return len;
1389 /*
1390 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space. Reporting
1391 * ENOBUFS might not be good (it's not tunable per se), but otherwise
1392 * we don't have a good statistic (IpOutDiscards but it can be too many
1393 * things). We could add another new stat but at least for now that
1394 * seems like overkill.
1395 */
1396 if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) {
1397 UDP6_INC_STATS(sock_net(sk),
1398 UDP_MIB_SNDBUFERRORS, is_udplite);
1399 }
1400 return err;
1401
1402 do_confirm:
1403 if (msg->msg_flags & MSG_PROBE)
1404 dst_confirm_neigh(dst, &fl6.daddr);
1405 if (!(msg->msg_flags&MSG_PROBE) || len)
1406 goto back_from_confirm;
1407 err = 0;
1408 goto out;
1409 }
1410
1411 void udpv6_destroy_sock(struct sock *sk)
1412 {
1413 struct udp_sock *up = udp_sk(sk);
1414 lock_sock(sk);
1415 udp_v6_flush_pending_frames(sk);
1416 release_sock(sk);
1417
1418 if (static_key_false(&udpv6_encap_needed) && up->encap_type) {
1419 void (*encap_destroy)(struct sock *sk);
1420 encap_destroy = ACCESS_ONCE(up->encap_destroy);
1421 if (encap_destroy)
1422 encap_destroy(sk);
1423 }
1424
1425 inet6_destroy_sock(sk);
1426 }
1427
1428 /*
1429 * Socket option code for UDP
1430 */
1431 int udpv6_setsockopt(struct sock *sk, int level, int optname,
1432 char __user *optval, unsigned int optlen)
1433 {
1434 if (level == SOL_UDP || level == SOL_UDPLITE)
1435 return udp_lib_setsockopt(sk, level, optname, optval, optlen,
1436 udp_v6_push_pending_frames);
1437 return ipv6_setsockopt(sk, level, optname, optval, optlen);
1438 }
1439
1440 #ifdef CONFIG_COMPAT
1441 int compat_udpv6_setsockopt(struct sock *sk, int level, int optname,
1442 char __user *optval, unsigned int optlen)
1443 {
1444 if (level == SOL_UDP || level == SOL_UDPLITE)
1445 return udp_lib_setsockopt(sk, level, optname, optval, optlen,
1446 udp_v6_push_pending_frames);
1447 return compat_ipv6_setsockopt(sk, level, optname, optval, optlen);
1448 }
1449 #endif
1450
1451 int udpv6_getsockopt(struct sock *sk, int level, int optname,
1452 char __user *optval, int __user *optlen)
1453 {
1454 if (level == SOL_UDP || level == SOL_UDPLITE)
1455 return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1456 return ipv6_getsockopt(sk, level, optname, optval, optlen);
1457 }
1458
1459 #ifdef CONFIG_COMPAT
1460 int compat_udpv6_getsockopt(struct sock *sk, int level, int optname,
1461 char __user *optval, int __user *optlen)
1462 {
1463 if (level == SOL_UDP || level == SOL_UDPLITE)
1464 return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1465 return compat_ipv6_getsockopt(sk, level, optname, optval, optlen);
1466 }
1467 #endif
1468
1469 static struct inet6_protocol udpv6_protocol = {
1470 .early_demux = udp_v6_early_demux,
1471 .early_demux_handler = udp_v6_early_demux,
1472 .handler = udpv6_rcv,
1473 .err_handler = udpv6_err,
1474 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1475 };
1476
1477 /* ------------------------------------------------------------------------ */
1478 #ifdef CONFIG_PROC_FS
1479 int udp6_seq_show(struct seq_file *seq, void *v)
1480 {
1481 if (v == SEQ_START_TOKEN) {
1482 seq_puts(seq, IPV6_SEQ_DGRAM_HEADER);
1483 } else {
1484 int bucket = ((struct udp_iter_state *)seq->private)->bucket;
1485 struct inet_sock *inet = inet_sk(v);
1486 __u16 srcp = ntohs(inet->inet_sport);
1487 __u16 destp = ntohs(inet->inet_dport);
1488 ip6_dgram_sock_seq_show(seq, v, srcp, destp, bucket);
1489 }
1490 return 0;
1491 }
1492
1493 static const struct file_operations udp6_afinfo_seq_fops = {
1494 .owner = THIS_MODULE,
1495 .open = udp_seq_open,
1496 .read = seq_read,
1497 .llseek = seq_lseek,
1498 .release = seq_release_net
1499 };
1500
1501 static struct udp_seq_afinfo udp6_seq_afinfo = {
1502 .name = "udp6",
1503 .family = AF_INET6,
1504 .udp_table = &udp_table,
1505 .seq_fops = &udp6_afinfo_seq_fops,
1506 .seq_ops = {
1507 .show = udp6_seq_show,
1508 },
1509 };
1510
1511 int __net_init udp6_proc_init(struct net *net)
1512 {
1513 return udp_proc_register(net, &udp6_seq_afinfo);
1514 }
1515
1516 void udp6_proc_exit(struct net *net)
1517 {
1518 udp_proc_unregister(net, &udp6_seq_afinfo);
1519 }
1520 #endif /* CONFIG_PROC_FS */
1521
1522 /* ------------------------------------------------------------------------ */
1523
1524 struct proto udpv6_prot = {
1525 .name = "UDPv6",
1526 .owner = THIS_MODULE,
1527 .close = udp_lib_close,
1528 .connect = ip6_datagram_connect,
1529 .disconnect = udp_disconnect,
1530 .ioctl = udp_ioctl,
1531 .init = udp_init_sock,
1532 .destroy = udpv6_destroy_sock,
1533 .setsockopt = udpv6_setsockopt,
1534 .getsockopt = udpv6_getsockopt,
1535 .sendmsg = udpv6_sendmsg,
1536 .recvmsg = udpv6_recvmsg,
1537 .release_cb = ip6_datagram_release_cb,
1538 .hash = udp_lib_hash,
1539 .unhash = udp_lib_unhash,
1540 .rehash = udp_v6_rehash,
1541 .get_port = udp_v6_get_port,
1542 .memory_allocated = &udp_memory_allocated,
1543 .sysctl_mem = sysctl_udp_mem,
1544 .sysctl_wmem = &sysctl_udp_wmem_min,
1545 .sysctl_rmem = &sysctl_udp_rmem_min,
1546 .obj_size = sizeof(struct udp6_sock),
1547 .h.udp_table = &udp_table,
1548 #ifdef CONFIG_COMPAT
1549 .compat_setsockopt = compat_udpv6_setsockopt,
1550 .compat_getsockopt = compat_udpv6_getsockopt,
1551 #endif
1552 .diag_destroy = udp_abort,
1553 };
1554
1555 static struct inet_protosw udpv6_protosw = {
1556 .type = SOCK_DGRAM,
1557 .protocol = IPPROTO_UDP,
1558 .prot = &udpv6_prot,
1559 .ops = &inet6_dgram_ops,
1560 .flags = INET_PROTOSW_PERMANENT,
1561 };
1562
1563 int __init udpv6_init(void)
1564 {
1565 int ret;
1566
1567 ret = inet6_add_protocol(&udpv6_protocol, IPPROTO_UDP);
1568 if (ret)
1569 goto out;
1570
1571 ret = inet6_register_protosw(&udpv6_protosw);
1572 if (ret)
1573 goto out_udpv6_protocol;
1574 out:
1575 return ret;
1576
1577 out_udpv6_protocol:
1578 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1579 goto out;
1580 }
1581
1582 void udpv6_exit(void)
1583 {
1584 inet6_unregister_protosw(&udpv6_protosw);
1585 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1586 }
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