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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/ndisc.h>
41#include <net/protocol.h>
42#include <net/transp_v6.h>
43#include <net/ip6_route.h>
44#include <net/raw.h>
45#include <net/tcp_states.h>
46#include <net/ip6_checksum.h>
47#include <net/xfrm.h>
48#include <net/inet6_hashtables.h>
49#include <net/busy_poll.h>
50
51#include <linux/proc_fs.h>
52#include <linux/seq_file.h>
53#include <trace/events/skb.h>
54#include "udp_impl.h"
55
56static unsigned int udp6_ehashfn(struct net *net,
57 const struct in6_addr *laddr,
58 const u16 lport,
59 const struct in6_addr *faddr,
60 const __be16 fport)
61{
62 static u32 udp6_ehash_secret __read_mostly;
63 static u32 udp_ipv6_hash_secret __read_mostly;
64
65 u32 lhash, fhash;
66
67 net_get_random_once(&udp6_ehash_secret,
68 sizeof(udp6_ehash_secret));
69 net_get_random_once(&udp_ipv6_hash_secret,
70 sizeof(udp_ipv6_hash_secret));
71
72 lhash = (__force u32)laddr->s6_addr32[3];
73 fhash = __ipv6_addr_jhash(faddr, udp_ipv6_hash_secret);
74
75 return __inet6_ehashfn(lhash, lport, fhash, fport,
76 udp_ipv6_hash_secret + net_hash_mix(net));
77}
78
79int ipv6_rcv_saddr_equal(const struct sock *sk, const struct sock *sk2)
80{
81 const struct in6_addr *sk2_rcv_saddr6 = inet6_rcv_saddr(sk2);
82 int sk_ipv6only = ipv6_only_sock(sk);
83 int sk2_ipv6only = inet_v6_ipv6only(sk2);
84 int addr_type = ipv6_addr_type(&sk->sk_v6_rcv_saddr);
85 int addr_type2 = sk2_rcv_saddr6 ? ipv6_addr_type(sk2_rcv_saddr6) : IPV6_ADDR_MAPPED;
86
87 /* if both are mapped, treat as IPv4 */
88 if (addr_type == IPV6_ADDR_MAPPED && addr_type2 == IPV6_ADDR_MAPPED)
89 return (!sk2_ipv6only &&
90 (!sk->sk_rcv_saddr || !sk2->sk_rcv_saddr ||
91 sk->sk_rcv_saddr == sk2->sk_rcv_saddr));
92
93 if (addr_type2 == IPV6_ADDR_ANY &&
94 !(sk2_ipv6only && addr_type == IPV6_ADDR_MAPPED))
95 return 1;
96
97 if (addr_type == IPV6_ADDR_ANY &&
98 !(sk_ipv6only && addr_type2 == IPV6_ADDR_MAPPED))
99 return 1;
100
101 if (sk2_rcv_saddr6 &&
102 ipv6_addr_equal(&sk->sk_v6_rcv_saddr, sk2_rcv_saddr6))
103 return 1;
104
105 return 0;
106}
107
108static unsigned int udp6_portaddr_hash(struct net *net,
109 const struct in6_addr *addr6,
110 unsigned int port)
111{
112 unsigned int hash, mix = net_hash_mix(net);
113
114 if (ipv6_addr_any(addr6))
115 hash = jhash_1word(0, mix);
116 else if (ipv6_addr_v4mapped(addr6))
117 hash = jhash_1word((__force u32)addr6->s6_addr32[3], mix);
118 else
119 hash = jhash2((__force u32 *)addr6->s6_addr32, 4, mix);
120
121 return hash ^ port;
122}
123
124
125int udp_v6_get_port(struct sock *sk, unsigned short snum)
126{
127 unsigned int hash2_nulladdr =
128 udp6_portaddr_hash(sock_net(sk), &in6addr_any, snum);
129 unsigned int hash2_partial =
130 udp6_portaddr_hash(sock_net(sk), &sk->sk_v6_rcv_saddr, 0);
131
132 /* precompute partial secondary hash */
133 udp_sk(sk)->udp_portaddr_hash = hash2_partial;
134 return udp_lib_get_port(sk, snum, ipv6_rcv_saddr_equal, hash2_nulladdr);
135}
136
137static void udp_v6_rehash(struct sock *sk)
138{
139 u16 new_hash = udp6_portaddr_hash(sock_net(sk),
140 &sk->sk_v6_rcv_saddr,
141 inet_sk(sk)->inet_num);
142
143 udp_lib_rehash(sk, new_hash);
144}
145
146static inline int compute_score(struct sock *sk, struct net *net,
147 unsigned short hnum,
148 const struct in6_addr *saddr, __be16 sport,
149 const struct in6_addr *daddr, __be16 dport,
150 int dif)
151{
152 int score = -1;
153
154 if (net_eq(sock_net(sk), net) && udp_sk(sk)->udp_port_hash == hnum &&
155 sk->sk_family == PF_INET6) {
156 struct inet_sock *inet = inet_sk(sk);
157
158 score = 0;
159 if (inet->inet_dport) {
160 if (inet->inet_dport != sport)
161 return -1;
162 score++;
163 }
164 if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr)) {
165 if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
166 return -1;
167 score++;
168 }
169 if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
170 if (!ipv6_addr_equal(&sk->sk_v6_daddr, saddr))
171 return -1;
172 score++;
173 }
174 if (sk->sk_bound_dev_if) {
175 if (sk->sk_bound_dev_if != dif)
176 return -1;
177 score++;
178 }
179 }
180 return score;
181}
182
183#define SCORE2_MAX (1 + 1 + 1)
184static inline int compute_score2(struct sock *sk, struct net *net,
185 const struct in6_addr *saddr, __be16 sport,
186 const struct in6_addr *daddr, unsigned short hnum,
187 int dif)
188{
189 int score = -1;
190
191 if (net_eq(sock_net(sk), net) && udp_sk(sk)->udp_port_hash == hnum &&
192 sk->sk_family == PF_INET6) {
193 struct inet_sock *inet = inet_sk(sk);
194
195 if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
196 return -1;
197 score = 0;
198 if (inet->inet_dport) {
199 if (inet->inet_dport != sport)
200 return -1;
201 score++;
202 }
203 if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
204 if (!ipv6_addr_equal(&sk->sk_v6_daddr, saddr))
205 return -1;
206 score++;
207 }
208 if (sk->sk_bound_dev_if) {
209 if (sk->sk_bound_dev_if != dif)
210 return -1;
211 score++;
212 }
213 }
214 return score;
215}
216
217
218/* called with read_rcu_lock() */
219static struct sock *udp6_lib_lookup2(struct net *net,
220 const struct in6_addr *saddr, __be16 sport,
221 const struct in6_addr *daddr, unsigned int hnum, int dif,
222 struct udp_hslot *hslot2, unsigned int slot2)
223{
224 struct sock *sk, *result;
225 struct hlist_nulls_node *node;
226 int score, badness, matches = 0, reuseport = 0;
227 u32 hash = 0;
228
229begin:
230 result = NULL;
231 badness = -1;
232 udp_portaddr_for_each_entry_rcu(sk, node, &hslot2->head) {
233 score = compute_score2(sk, net, saddr, sport,
234 daddr, hnum, dif);
235 if (score > badness) {
236 result = sk;
237 badness = score;
238 reuseport = sk->sk_reuseport;
239 if (reuseport) {
240 hash = udp6_ehashfn(net, daddr, hnum,
241 saddr, sport);
242 matches = 1;
243 } else if (score == SCORE2_MAX)
244 goto exact_match;
245 } else if (score == badness && reuseport) {
246 matches++;
247 if (((u64)hash * matches) >> 32 == 0)
248 result = sk;
249 hash = next_pseudo_random32(hash);
250 }
251 }
252 /*
253 * if the nulls value we got at the end of this lookup is
254 * not the expected one, we must restart lookup.
255 * We probably met an item that was moved to another chain.
256 */
257 if (get_nulls_value(node) != slot2)
258 goto begin;
259
260 if (result) {
261exact_match:
262 if (unlikely(!atomic_inc_not_zero_hint(&result->sk_refcnt, 2)))
263 result = NULL;
264 else if (unlikely(compute_score2(result, net, saddr, sport,
265 daddr, hnum, dif) < badness)) {
266 sock_put(result);
267 goto begin;
268 }
269 }
270 return result;
271}
272
273struct sock *__udp6_lib_lookup(struct net *net,
274 const struct in6_addr *saddr, __be16 sport,
275 const struct in6_addr *daddr, __be16 dport,
276 int dif, struct udp_table *udptable)
277{
278 struct sock *sk, *result;
279 struct hlist_nulls_node *node;
280 unsigned short hnum = ntohs(dport);
281 unsigned int hash2, slot2, slot = udp_hashfn(net, hnum, udptable->mask);
282 struct udp_hslot *hslot2, *hslot = &udptable->hash[slot];
283 int score, badness, matches = 0, reuseport = 0;
284 u32 hash = 0;
285
286 rcu_read_lock();
287 if (hslot->count > 10) {
288 hash2 = udp6_portaddr_hash(net, daddr, hnum);
289 slot2 = hash2 & udptable->mask;
290 hslot2 = &udptable->hash2[slot2];
291 if (hslot->count < hslot2->count)
292 goto begin;
293
294 result = udp6_lib_lookup2(net, saddr, sport,
295 daddr, hnum, dif,
296 hslot2, slot2);
297 if (!result) {
298 hash2 = udp6_portaddr_hash(net, &in6addr_any, hnum);
299 slot2 = hash2 & udptable->mask;
300 hslot2 = &udptable->hash2[slot2];
301 if (hslot->count < hslot2->count)
302 goto begin;
303
304 result = udp6_lib_lookup2(net, saddr, sport,
305 &in6addr_any, hnum, dif,
306 hslot2, slot2);
307 }
308 rcu_read_unlock();
309 return result;
310 }
311begin:
312 result = NULL;
313 badness = -1;
314 sk_nulls_for_each_rcu(sk, node, &hslot->head) {
315 score = compute_score(sk, net, hnum, saddr, sport, daddr, dport, dif);
316 if (score > badness) {
317 result = sk;
318 badness = score;
319 reuseport = sk->sk_reuseport;
320 if (reuseport) {
321 hash = udp6_ehashfn(net, daddr, hnum,
322 saddr, sport);
323 matches = 1;
324 }
325 } else if (score == badness && reuseport) {
326 matches++;
327 if (((u64)hash * matches) >> 32 == 0)
328 result = sk;
329 hash = next_pseudo_random32(hash);
330 }
331 }
332 /*
333 * if the nulls value we got at the end of this lookup is
334 * not the expected one, we must restart lookup.
335 * We probably met an item that was moved to another chain.
336 */
337 if (get_nulls_value(node) != slot)
338 goto begin;
339
340 if (result) {
341 if (unlikely(!atomic_inc_not_zero_hint(&result->sk_refcnt, 2)))
342 result = NULL;
343 else if (unlikely(compute_score(result, net, hnum, saddr, sport,
344 daddr, dport, dif) < badness)) {
345 sock_put(result);
346 goto begin;
347 }
348 }
349 rcu_read_unlock();
350 return result;
351}
352EXPORT_SYMBOL_GPL(__udp6_lib_lookup);
353
354static struct sock *__udp6_lib_lookup_skb(struct sk_buff *skb,
355 __be16 sport, __be16 dport,
356 struct udp_table *udptable)
357{
358 struct sock *sk;
359 const struct ipv6hdr *iph = ipv6_hdr(skb);
360
361 if (unlikely(sk = skb_steal_sock(skb)))
362 return sk;
363 return __udp6_lib_lookup(dev_net(skb_dst(skb)->dev), &iph->saddr, sport,
364 &iph->daddr, dport, inet6_iif(skb),
365 udptable);
366}
367
368struct sock *udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport,
369 const struct in6_addr *daddr, __be16 dport, int dif)
370{
371 return __udp6_lib_lookup(net, saddr, sport, daddr, dport, dif, &udp_table);
372}
373EXPORT_SYMBOL_GPL(udp6_lib_lookup);
374
375
376/*
377 * This should be easy, if there is something there we
378 * return it, otherwise we block.
379 */
380
381int udpv6_recvmsg(struct kiocb *iocb, struct sock *sk,
382 struct msghdr *msg, size_t len,
383 int noblock, int flags, int *addr_len)
384{
385 struct ipv6_pinfo *np = inet6_sk(sk);
386 struct inet_sock *inet = inet_sk(sk);
387 struct sk_buff *skb;
388 unsigned int ulen, copied;
389 int peeked, off = 0;
390 int err;
391 int is_udplite = IS_UDPLITE(sk);
392 int is_udp4;
393 bool slow;
394
395 if (flags & MSG_ERRQUEUE)
396 return ipv6_recv_error(sk, msg, len, addr_len);
397
398 if (np->rxpmtu && np->rxopt.bits.rxpmtu)
399 return ipv6_recv_rxpmtu(sk, msg, len, addr_len);
400
401try_again:
402 skb = __skb_recv_datagram(sk, flags | (noblock ? MSG_DONTWAIT : 0),
403 &peeked, &off, &err);
404 if (!skb)
405 goto out;
406
407 ulen = skb->len - sizeof(struct udphdr);
408 copied = len;
409 if (copied > ulen)
410 copied = ulen;
411 else if (copied < ulen)
412 msg->msg_flags |= MSG_TRUNC;
413
414 is_udp4 = (skb->protocol == htons(ETH_P_IP));
415
416 /*
417 * If checksum is needed at all, try to do it while copying the
418 * data. If the data is truncated, or if we only want a partial
419 * coverage checksum (UDP-Lite), do it before the copy.
420 */
421
422 if (copied < ulen || UDP_SKB_CB(skb)->partial_cov) {
423 if (udp_lib_checksum_complete(skb))
424 goto csum_copy_err;
425 }
426
427 if (skb_csum_unnecessary(skb))
428 err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr),
429 msg->msg_iov, copied);
430 else {
431 err = skb_copy_and_csum_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov);
432 if (err == -EINVAL)
433 goto csum_copy_err;
434 }
435 if (unlikely(err)) {
436 trace_kfree_skb(skb, udpv6_recvmsg);
437 if (!peeked) {
438 atomic_inc(&sk->sk_drops);
439 if (is_udp4)
440 UDP_INC_STATS_USER(sock_net(sk),
441 UDP_MIB_INERRORS,
442 is_udplite);
443 else
444 UDP6_INC_STATS_USER(sock_net(sk),
445 UDP_MIB_INERRORS,
446 is_udplite);
447 }
448 goto out_free;
449 }
450 if (!peeked) {
451 if (is_udp4)
452 UDP_INC_STATS_USER(sock_net(sk),
453 UDP_MIB_INDATAGRAMS, is_udplite);
454 else
455 UDP6_INC_STATS_USER(sock_net(sk),
456 UDP_MIB_INDATAGRAMS, is_udplite);
457 }
458
459 sock_recv_ts_and_drops(msg, sk, skb);
460
461 /* Copy the address. */
462 if (msg->msg_name) {
463 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
464 sin6->sin6_family = AF_INET6;
465 sin6->sin6_port = udp_hdr(skb)->source;
466 sin6->sin6_flowinfo = 0;
467
468 if (is_udp4) {
469 ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
470 &sin6->sin6_addr);
471 sin6->sin6_scope_id = 0;
472 } else {
473 sin6->sin6_addr = ipv6_hdr(skb)->saddr;
474 sin6->sin6_scope_id =
475 ipv6_iface_scope_id(&sin6->sin6_addr,
476 IP6CB(skb)->iif);
477 }
478 *addr_len = sizeof(*sin6);
479 }
480
481 if (np->rxopt.all)
482 ip6_datagram_recv_common_ctl(sk, msg, skb);
483
484 if (is_udp4) {
485 if (inet->cmsg_flags)
486 ip_cmsg_recv(msg, skb);
487 } else {
488 if (np->rxopt.all)
489 ip6_datagram_recv_specific_ctl(sk, msg, skb);
490 }
491
492 err = copied;
493 if (flags & MSG_TRUNC)
494 err = ulen;
495
496out_free:
497 skb_free_datagram_locked(sk, skb);
498out:
499 return err;
500
501csum_copy_err:
502 slow = lock_sock_fast(sk);
503 if (!skb_kill_datagram(sk, skb, flags)) {
504 if (is_udp4) {
505 UDP_INC_STATS_USER(sock_net(sk),
506 UDP_MIB_CSUMERRORS, is_udplite);
507 UDP_INC_STATS_USER(sock_net(sk),
508 UDP_MIB_INERRORS, is_udplite);
509 } else {
510 UDP6_INC_STATS_USER(sock_net(sk),
511 UDP_MIB_CSUMERRORS, is_udplite);
512 UDP6_INC_STATS_USER(sock_net(sk),
513 UDP_MIB_INERRORS, is_udplite);
514 }
515 }
516 unlock_sock_fast(sk, slow);
517
518 if (noblock)
519 return -EAGAIN;
520
521 /* starting over for a new packet */
522 msg->msg_flags &= ~MSG_TRUNC;
523 goto try_again;
524}
525
526void __udp6_lib_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
527 u8 type, u8 code, int offset, __be32 info,
528 struct udp_table *udptable)
529{
530 struct ipv6_pinfo *np;
531 const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data;
532 const struct in6_addr *saddr = &hdr->saddr;
533 const struct in6_addr *daddr = &hdr->daddr;
534 struct udphdr *uh = (struct udphdr*)(skb->data+offset);
535 struct sock *sk;
536 int err;
537
538 sk = __udp6_lib_lookup(dev_net(skb->dev), daddr, uh->dest,
539 saddr, uh->source, inet6_iif(skb), udptable);
540 if (sk == NULL)
541 return;
542
543 if (type == ICMPV6_PKT_TOOBIG) {
544 if (!ip6_sk_accept_pmtu(sk))
545 goto out;
546 ip6_sk_update_pmtu(skb, sk, info);
547 }
548 if (type == NDISC_REDIRECT) {
549 ip6_sk_redirect(skb, sk);
550 goto out;
551 }
552
553 np = inet6_sk(sk);
554
555 if (!icmpv6_err_convert(type, code, &err) && !np->recverr)
556 goto out;
557
558 if (sk->sk_state != TCP_ESTABLISHED && !np->recverr)
559 goto out;
560
561 if (np->recverr)
562 ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1));
563
564 sk->sk_err = err;
565 sk->sk_error_report(sk);
566out:
567 sock_put(sk);
568}
569
570static int __udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
571{
572 int rc;
573
574 if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
575 sock_rps_save_rxhash(sk, skb);
576 sk_mark_napi_id(sk, skb);
577 }
578
579 rc = sock_queue_rcv_skb(sk, skb);
580 if (rc < 0) {
581 int is_udplite = IS_UDPLITE(sk);
582
583 /* Note that an ENOMEM error is charged twice */
584 if (rc == -ENOMEM)
585 UDP6_INC_STATS_BH(sock_net(sk),
586 UDP_MIB_RCVBUFERRORS, is_udplite);
587 UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
588 kfree_skb(skb);
589 return -1;
590 }
591 return 0;
592}
593
594static __inline__ void udpv6_err(struct sk_buff *skb,
595 struct inet6_skb_parm *opt, u8 type,
596 u8 code, int offset, __be32 info )
597{
598 __udp6_lib_err(skb, opt, type, code, offset, info, &udp_table);
599}
600
601static struct static_key udpv6_encap_needed __read_mostly;
602void udpv6_encap_enable(void)
603{
604 if (!static_key_enabled(&udpv6_encap_needed))
605 static_key_slow_inc(&udpv6_encap_needed);
606}
607EXPORT_SYMBOL(udpv6_encap_enable);
608
609int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
610{
611 struct udp_sock *up = udp_sk(sk);
612 int rc;
613 int is_udplite = IS_UDPLITE(sk);
614
615 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
616 goto drop;
617
618 if (static_key_false(&udpv6_encap_needed) && up->encap_type) {
619 int (*encap_rcv)(struct sock *sk, struct sk_buff *skb);
620
621 /*
622 * This is an encapsulation socket so pass the skb to
623 * the socket's udp_encap_rcv() hook. Otherwise, just
624 * fall through and pass this up the UDP socket.
625 * up->encap_rcv() returns the following value:
626 * =0 if skb was successfully passed to the encap
627 * handler or was discarded by it.
628 * >0 if skb should be passed on to UDP.
629 * <0 if skb should be resubmitted as proto -N
630 */
631
632 /* if we're overly short, let UDP handle it */
633 encap_rcv = ACCESS_ONCE(up->encap_rcv);
634 if (skb->len > sizeof(struct udphdr) && encap_rcv != NULL) {
635 int ret;
636
637 ret = encap_rcv(sk, skb);
638 if (ret <= 0) {
639 UDP_INC_STATS_BH(sock_net(sk),
640 UDP_MIB_INDATAGRAMS,
641 is_udplite);
642 return -ret;
643 }
644 }
645
646 /* FALLTHROUGH -- it's a UDP Packet */
647 }
648
649 /*
650 * UDP-Lite specific tests, ignored on UDP sockets (see net/ipv4/udp.c).
651 */
652 if ((is_udplite & UDPLITE_RECV_CC) && UDP_SKB_CB(skb)->partial_cov) {
653
654 if (up->pcrlen == 0) { /* full coverage was set */
655 LIMIT_NETDEBUG(KERN_WARNING "UDPLITE6: partial coverage"
656 " %d while full coverage %d requested\n",
657 UDP_SKB_CB(skb)->cscov, skb->len);
658 goto drop;
659 }
660 if (UDP_SKB_CB(skb)->cscov < up->pcrlen) {
661 LIMIT_NETDEBUG(KERN_WARNING "UDPLITE6: coverage %d "
662 "too small, need min %d\n",
663 UDP_SKB_CB(skb)->cscov, up->pcrlen);
664 goto drop;
665 }
666 }
667
668 if (rcu_access_pointer(sk->sk_filter)) {
669 if (udp_lib_checksum_complete(skb))
670 goto csum_error;
671 }
672
673 if (sk_rcvqueues_full(sk, skb, sk->sk_rcvbuf))
674 goto drop;
675
676 skb_dst_drop(skb);
677
678 bh_lock_sock(sk);
679 rc = 0;
680 if (!sock_owned_by_user(sk))
681 rc = __udpv6_queue_rcv_skb(sk, skb);
682 else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) {
683 bh_unlock_sock(sk);
684 goto drop;
685 }
686 bh_unlock_sock(sk);
687
688 return rc;
689csum_error:
690 UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite);
691drop:
692 UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
693 atomic_inc(&sk->sk_drops);
694 kfree_skb(skb);
695 return -1;
696}
697
698static struct sock *udp_v6_mcast_next(struct net *net, struct sock *sk,
699 __be16 loc_port, const struct in6_addr *loc_addr,
700 __be16 rmt_port, const struct in6_addr *rmt_addr,
701 int dif)
702{
703 struct hlist_nulls_node *node;
704 struct sock *s = sk;
705 unsigned short num = ntohs(loc_port);
706
707 sk_nulls_for_each_from(s, node) {
708 struct inet_sock *inet = inet_sk(s);
709
710 if (!net_eq(sock_net(s), net))
711 continue;
712
713 if (udp_sk(s)->udp_port_hash == num &&
714 s->sk_family == PF_INET6) {
715 if (inet->inet_dport) {
716 if (inet->inet_dport != rmt_port)
717 continue;
718 }
719 if (!ipv6_addr_any(&sk->sk_v6_daddr) &&
720 !ipv6_addr_equal(&sk->sk_v6_daddr, rmt_addr))
721 continue;
722
723 if (s->sk_bound_dev_if && s->sk_bound_dev_if != dif)
724 continue;
725
726 if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr)) {
727 if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, loc_addr))
728 continue;
729 }
730 if (!inet6_mc_check(s, loc_addr, rmt_addr))
731 continue;
732 return s;
733 }
734 }
735 return NULL;
736}
737
738static void flush_stack(struct sock **stack, unsigned int count,
739 struct sk_buff *skb, unsigned int final)
740{
741 struct sk_buff *skb1 = NULL;
742 struct sock *sk;
743 unsigned int i;
744
745 for (i = 0; i < count; i++) {
746 sk = stack[i];
747 if (likely(skb1 == NULL))
748 skb1 = (i == final) ? skb : skb_clone(skb, GFP_ATOMIC);
749 if (!skb1) {
750 atomic_inc(&sk->sk_drops);
751 UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_RCVBUFERRORS,
752 IS_UDPLITE(sk));
753 UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS,
754 IS_UDPLITE(sk));
755 }
756
757 if (skb1 && udpv6_queue_rcv_skb(sk, skb1) <= 0)
758 skb1 = NULL;
759 }
760 if (unlikely(skb1))
761 kfree_skb(skb1);
762}
763/*
764 * Note: called only from the BH handler context,
765 * so we don't need to lock the hashes.
766 */
767static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
768 const struct in6_addr *saddr, const struct in6_addr *daddr,
769 struct udp_table *udptable)
770{
771 struct sock *sk, *stack[256 / sizeof(struct sock *)];
772 const struct udphdr *uh = udp_hdr(skb);
773 struct udp_hslot *hslot = udp_hashslot(udptable, net, ntohs(uh->dest));
774 int dif;
775 unsigned int i, count = 0;
776
777 spin_lock(&hslot->lock);
778 sk = sk_nulls_head(&hslot->head);
779 dif = inet6_iif(skb);
780 sk = udp_v6_mcast_next(net, sk, uh->dest, daddr, uh->source, saddr, dif);
781 while (sk) {
782 stack[count++] = sk;
783 sk = udp_v6_mcast_next(net, sk_nulls_next(sk), uh->dest, daddr,
784 uh->source, saddr, dif);
785 if (unlikely(count == ARRAY_SIZE(stack))) {
786 if (!sk)
787 break;
788 flush_stack(stack, count, skb, ~0);
789 count = 0;
790 }
791 }
792 /*
793 * before releasing the lock, we must take reference on sockets
794 */
795 for (i = 0; i < count; i++)
796 sock_hold(stack[i]);
797
798 spin_unlock(&hslot->lock);
799
800 if (count) {
801 flush_stack(stack, count, skb, count - 1);
802
803 for (i = 0; i < count; i++)
804 sock_put(stack[i]);
805 } else {
806 kfree_skb(skb);
807 }
808 return 0;
809}
810
811int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
812 int proto)
813{
814 struct net *net = dev_net(skb->dev);
815 struct sock *sk;
816 struct udphdr *uh;
817 const struct in6_addr *saddr, *daddr;
818 u32 ulen = 0;
819
820 if (!pskb_may_pull(skb, sizeof(struct udphdr)))
821 goto discard;
822
823 saddr = &ipv6_hdr(skb)->saddr;
824 daddr = &ipv6_hdr(skb)->daddr;
825 uh = udp_hdr(skb);
826
827 ulen = ntohs(uh->len);
828 if (ulen > skb->len)
829 goto short_packet;
830
831 if (proto == IPPROTO_UDP) {
832 /* UDP validates ulen. */
833
834 /* Check for jumbo payload */
835 if (ulen == 0)
836 ulen = skb->len;
837
838 if (ulen < sizeof(*uh))
839 goto short_packet;
840
841 if (ulen < skb->len) {
842 if (pskb_trim_rcsum(skb, ulen))
843 goto short_packet;
844 saddr = &ipv6_hdr(skb)->saddr;
845 daddr = &ipv6_hdr(skb)->daddr;
846 uh = udp_hdr(skb);
847 }
848 }
849
850 if (udp6_csum_init(skb, uh, proto))
851 goto csum_error;
852
853 /*
854 * Multicast receive code
855 */
856 if (ipv6_addr_is_multicast(daddr))
857 return __udp6_lib_mcast_deliver(net, skb,
858 saddr, daddr, udptable);
859
860 /* Unicast */
861
862 /*
863 * check socket cache ... must talk to Alan about his plans
864 * for sock caches... i'll skip this for now.
865 */
866 sk = __udp6_lib_lookup_skb(skb, uh->source, uh->dest, udptable);
867 if (sk != NULL) {
868 int ret;
869
870 ret = udpv6_queue_rcv_skb(sk, skb);
871 sock_put(sk);
872
873 /* a return value > 0 means to resubmit the input, but
874 * it wants the return to be -protocol, or 0
875 */
876 if (ret > 0)
877 return -ret;
878
879 return 0;
880 }
881
882 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
883 goto discard;
884
885 if (udp_lib_checksum_complete(skb))
886 goto csum_error;
887
888 UDP6_INC_STATS_BH(net, UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE);
889 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
890
891 kfree_skb(skb);
892 return 0;
893
894short_packet:
895 LIMIT_NETDEBUG(KERN_DEBUG "UDP%sv6: short packet: From [%pI6c]:%u %d/%d to [%pI6c]:%u\n",
896 proto == IPPROTO_UDPLITE ? "-Lite" : "",
897 saddr,
898 ntohs(uh->source),
899 ulen,
900 skb->len,
901 daddr,
902 ntohs(uh->dest));
903 goto discard;
904csum_error:
905 UDP6_INC_STATS_BH(net, UDP_MIB_CSUMERRORS, proto == IPPROTO_UDPLITE);
906discard:
907 UDP6_INC_STATS_BH(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE);
908 kfree_skb(skb);
909 return 0;
910}
911
912static __inline__ int udpv6_rcv(struct sk_buff *skb)
913{
914 return __udp6_lib_rcv(skb, &udp_table, IPPROTO_UDP);
915}
916
917/*
918 * Throw away all pending data and cancel the corking. Socket is locked.
919 */
920static void udp_v6_flush_pending_frames(struct sock *sk)
921{
922 struct udp_sock *up = udp_sk(sk);
923
924 if (up->pending == AF_INET)
925 udp_flush_pending_frames(sk);
926 else if (up->pending) {
927 up->len = 0;
928 up->pending = 0;
929 ip6_flush_pending_frames(sk);
930 }
931}
932
933/**
934 * udp6_hwcsum_outgoing - handle outgoing HW checksumming
935 * @sk: socket we are sending on
936 * @skb: sk_buff containing the filled-in UDP header
937 * (checksum field must be zeroed out)
938 */
939static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb,
940 const struct in6_addr *saddr,
941 const struct in6_addr *daddr, int len)
942{
943 unsigned int offset;
944 struct udphdr *uh = udp_hdr(skb);
945 __wsum csum = 0;
946
947 if (skb_queue_len(&sk->sk_write_queue) == 1) {
948 /* Only one fragment on the socket. */
949 skb->csum_start = skb_transport_header(skb) - skb->head;
950 skb->csum_offset = offsetof(struct udphdr, check);
951 uh->check = ~csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 0);
952 } else {
953 /*
954 * HW-checksum won't work as there are two or more
955 * fragments on the socket so that all csums of sk_buffs
956 * should be together
957 */
958 offset = skb_transport_offset(skb);
959 skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
960
961 skb->ip_summed = CHECKSUM_NONE;
962
963 skb_queue_walk(&sk->sk_write_queue, skb) {
964 csum = csum_add(csum, skb->csum);
965 }
966
967 uh->check = csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP,
968 csum);
969 if (uh->check == 0)
970 uh->check = CSUM_MANGLED_0;
971 }
972}
973
974/*
975 * Sending
976 */
977
978static int udp_v6_push_pending_frames(struct sock *sk)
979{
980 struct sk_buff *skb;
981 struct udphdr *uh;
982 struct udp_sock *up = udp_sk(sk);
983 struct inet_sock *inet = inet_sk(sk);
984 struct flowi6 *fl6;
985 int err = 0;
986 int is_udplite = IS_UDPLITE(sk);
987 __wsum csum = 0;
988
989 if (up->pending == AF_INET)
990 return udp_push_pending_frames(sk);
991
992 fl6 = &inet->cork.fl.u.ip6;
993
994 /* Grab the skbuff where UDP header space exists. */
995 if ((skb = skb_peek(&sk->sk_write_queue)) == NULL)
996 goto out;
997
998 /*
999 * Create a UDP header
1000 */
1001 uh = udp_hdr(skb);
1002 uh->source = fl6->fl6_sport;
1003 uh->dest = fl6->fl6_dport;
1004 uh->len = htons(up->len);
1005 uh->check = 0;
1006
1007 if (is_udplite)
1008 csum = udplite_csum_outgoing(sk, skb);
1009 else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */
1010 udp6_hwcsum_outgoing(sk, skb, &fl6->saddr, &fl6->daddr,
1011 up->len);
1012 goto send;
1013 } else
1014 csum = udp_csum_outgoing(sk, skb);
1015
1016 /* add protocol-dependent pseudo-header */
1017 uh->check = csum_ipv6_magic(&fl6->saddr, &fl6->daddr,
1018 up->len, fl6->flowi6_proto, csum);
1019 if (uh->check == 0)
1020 uh->check = CSUM_MANGLED_0;
1021
1022send:
1023 err = ip6_push_pending_frames(sk);
1024 if (err) {
1025 if (err == -ENOBUFS && !inet6_sk(sk)->recverr) {
1026 UDP6_INC_STATS_USER(sock_net(sk),
1027 UDP_MIB_SNDBUFERRORS, is_udplite);
1028 err = 0;
1029 }
1030 } else
1031 UDP6_INC_STATS_USER(sock_net(sk),
1032 UDP_MIB_OUTDATAGRAMS, is_udplite);
1033out:
1034 up->len = 0;
1035 up->pending = 0;
1036 return err;
1037}
1038
1039int udpv6_sendmsg(struct kiocb *iocb, struct sock *sk,
1040 struct msghdr *msg, size_t len)
1041{
1042 struct ipv6_txoptions opt_space;
1043 struct udp_sock *up = udp_sk(sk);
1044 struct inet_sock *inet = inet_sk(sk);
1045 struct ipv6_pinfo *np = inet6_sk(sk);
1046 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
1047 struct in6_addr *daddr, *final_p, final;
1048 struct ipv6_txoptions *opt = NULL;
1049 struct ip6_flowlabel *flowlabel = NULL;
1050 struct flowi6 fl6;
1051 struct dst_entry *dst;
1052 int addr_len = msg->msg_namelen;
1053 int ulen = len;
1054 int hlimit = -1;
1055 int tclass = -1;
1056 int dontfrag = -1;
1057 int corkreq = up->corkflag || msg->msg_flags&MSG_MORE;
1058 int err;
1059 int connected = 0;
1060 int is_udplite = IS_UDPLITE(sk);
1061 int (*getfrag)(void *, char *, int, int, int, struct sk_buff *);
1062
1063 /* destination address check */
1064 if (sin6) {
1065 if (addr_len < offsetof(struct sockaddr, sa_data))
1066 return -EINVAL;
1067
1068 switch (sin6->sin6_family) {
1069 case AF_INET6:
1070 if (addr_len < SIN6_LEN_RFC2133)
1071 return -EINVAL;
1072 daddr = &sin6->sin6_addr;
1073 break;
1074 case AF_INET:
1075 goto do_udp_sendmsg;
1076 case AF_UNSPEC:
1077 msg->msg_name = sin6 = NULL;
1078 msg->msg_namelen = addr_len = 0;
1079 daddr = NULL;
1080 break;
1081 default:
1082 return -EINVAL;
1083 }
1084 } else if (!up->pending) {
1085 if (sk->sk_state != TCP_ESTABLISHED)
1086 return -EDESTADDRREQ;
1087 daddr = &sk->sk_v6_daddr;
1088 } else
1089 daddr = NULL;
1090
1091 if (daddr) {
1092 if (ipv6_addr_v4mapped(daddr)) {
1093 struct sockaddr_in sin;
1094 sin.sin_family = AF_INET;
1095 sin.sin_port = sin6 ? sin6->sin6_port : inet->inet_dport;
1096 sin.sin_addr.s_addr = daddr->s6_addr32[3];
1097 msg->msg_name = &sin;
1098 msg->msg_namelen = sizeof(sin);
1099do_udp_sendmsg:
1100 if (__ipv6_only_sock(sk))
1101 return -ENETUNREACH;
1102 return udp_sendmsg(iocb, sk, msg, len);
1103 }
1104 }
1105
1106 if (up->pending == AF_INET)
1107 return udp_sendmsg(iocb, sk, msg, len);
1108
1109 /* Rough check on arithmetic overflow,
1110 better check is made in ip6_append_data().
1111 */
1112 if (len > INT_MAX - sizeof(struct udphdr))
1113 return -EMSGSIZE;
1114
1115 if (up->pending) {
1116 /*
1117 * There are pending frames.
1118 * The socket lock must be held while it's corked.
1119 */
1120 lock_sock(sk);
1121 if (likely(up->pending)) {
1122 if (unlikely(up->pending != AF_INET6)) {
1123 release_sock(sk);
1124 return -EAFNOSUPPORT;
1125 }
1126 dst = NULL;
1127 goto do_append_data;
1128 }
1129 release_sock(sk);
1130 }
1131 ulen += sizeof(struct udphdr);
1132
1133 memset(&fl6, 0, sizeof(fl6));
1134
1135 if (sin6) {
1136 if (sin6->sin6_port == 0)
1137 return -EINVAL;
1138
1139 fl6.fl6_dport = sin6->sin6_port;
1140 daddr = &sin6->sin6_addr;
1141
1142 if (np->sndflow) {
1143 fl6.flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK;
1144 if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) {
1145 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1146 if (flowlabel == NULL)
1147 return -EINVAL;
1148 }
1149 }
1150
1151 /*
1152 * Otherwise it will be difficult to maintain
1153 * sk->sk_dst_cache.
1154 */
1155 if (sk->sk_state == TCP_ESTABLISHED &&
1156 ipv6_addr_equal(daddr, &sk->sk_v6_daddr))
1157 daddr = &sk->sk_v6_daddr;
1158
1159 if (addr_len >= sizeof(struct sockaddr_in6) &&
1160 sin6->sin6_scope_id &&
1161 __ipv6_addr_needs_scope_id(__ipv6_addr_type(daddr)))
1162 fl6.flowi6_oif = sin6->sin6_scope_id;
1163 } else {
1164 if (sk->sk_state != TCP_ESTABLISHED)
1165 return -EDESTADDRREQ;
1166
1167 fl6.fl6_dport = inet->inet_dport;
1168 daddr = &sk->sk_v6_daddr;
1169 fl6.flowlabel = np->flow_label;
1170 connected = 1;
1171 }
1172
1173 if (!fl6.flowi6_oif)
1174 fl6.flowi6_oif = sk->sk_bound_dev_if;
1175
1176 if (!fl6.flowi6_oif)
1177 fl6.flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;
1178
1179 fl6.flowi6_mark = sk->sk_mark;
1180
1181 if (msg->msg_controllen) {
1182 opt = &opt_space;
1183 memset(opt, 0, sizeof(struct ipv6_txoptions));
1184 opt->tot_len = sizeof(*opt);
1185
1186 err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, &fl6, opt,
1187 &hlimit, &tclass, &dontfrag);
1188 if (err < 0) {
1189 fl6_sock_release(flowlabel);
1190 return err;
1191 }
1192 if ((fl6.flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) {
1193 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1194 if (flowlabel == NULL)
1195 return -EINVAL;
1196 }
1197 if (!(opt->opt_nflen|opt->opt_flen))
1198 opt = NULL;
1199 connected = 0;
1200 }
1201 if (opt == NULL)
1202 opt = np->opt;
1203 if (flowlabel)
1204 opt = fl6_merge_options(&opt_space, flowlabel, opt);
1205 opt = ipv6_fixup_options(&opt_space, opt);
1206
1207 fl6.flowi6_proto = sk->sk_protocol;
1208 if (!ipv6_addr_any(daddr))
1209 fl6.daddr = *daddr;
1210 else
1211 fl6.daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */
1212 if (ipv6_addr_any(&fl6.saddr) && !ipv6_addr_any(&np->saddr))
1213 fl6.saddr = np->saddr;
1214 fl6.fl6_sport = inet->inet_sport;
1215
1216 final_p = fl6_update_dst(&fl6, opt, &final);
1217 if (final_p)
1218 connected = 0;
1219
1220 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr)) {
1221 fl6.flowi6_oif = np->mcast_oif;
1222 connected = 0;
1223 } else if (!fl6.flowi6_oif)
1224 fl6.flowi6_oif = np->ucast_oif;
1225
1226 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
1227
1228 dst = ip6_sk_dst_lookup_flow(sk, &fl6, final_p);
1229 if (IS_ERR(dst)) {
1230 err = PTR_ERR(dst);
1231 dst = NULL;
1232 goto out;
1233 }
1234
1235 if (hlimit < 0) {
1236 if (ipv6_addr_is_multicast(&fl6.daddr))
1237 hlimit = np->mcast_hops;
1238 else
1239 hlimit = np->hop_limit;
1240 if (hlimit < 0)
1241 hlimit = ip6_dst_hoplimit(dst);
1242 }
1243
1244 if (tclass < 0)
1245 tclass = np->tclass;
1246
1247 if (msg->msg_flags&MSG_CONFIRM)
1248 goto do_confirm;
1249back_from_confirm:
1250
1251 lock_sock(sk);
1252 if (unlikely(up->pending)) {
1253 /* The socket is already corked while preparing it. */
1254 /* ... which is an evident application bug. --ANK */
1255 release_sock(sk);
1256
1257 LIMIT_NETDEBUG(KERN_DEBUG "udp cork app bug 2\n");
1258 err = -EINVAL;
1259 goto out;
1260 }
1261
1262 up->pending = AF_INET6;
1263
1264do_append_data:
1265 if (dontfrag < 0)
1266 dontfrag = np->dontfrag;
1267 up->len += ulen;
1268 getfrag = is_udplite ? udplite_getfrag : ip_generic_getfrag;
1269 err = ip6_append_data(sk, getfrag, msg->msg_iov, ulen,
1270 sizeof(struct udphdr), hlimit, tclass, opt, &fl6,
1271 (struct rt6_info*)dst,
1272 corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags, dontfrag);
1273 if (err)
1274 udp_v6_flush_pending_frames(sk);
1275 else if (!corkreq)
1276 err = udp_v6_push_pending_frames(sk);
1277 else if (unlikely(skb_queue_empty(&sk->sk_write_queue)))
1278 up->pending = 0;
1279
1280 if (dst) {
1281 if (connected) {
1282 ip6_dst_store(sk, dst,
1283 ipv6_addr_equal(&fl6.daddr, &sk->sk_v6_daddr) ?
1284 &sk->sk_v6_daddr : NULL,
1285#ifdef CONFIG_IPV6_SUBTREES
1286 ipv6_addr_equal(&fl6.saddr, &np->saddr) ?
1287 &np->saddr :
1288#endif
1289 NULL);
1290 } else {
1291 dst_release(dst);
1292 }
1293 dst = NULL;
1294 }
1295
1296 if (err > 0)
1297 err = np->recverr ? net_xmit_errno(err) : 0;
1298 release_sock(sk);
1299out:
1300 dst_release(dst);
1301 fl6_sock_release(flowlabel);
1302 if (!err)
1303 return len;
1304 /*
1305 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space. Reporting
1306 * ENOBUFS might not be good (it's not tunable per se), but otherwise
1307 * we don't have a good statistic (IpOutDiscards but it can be too many
1308 * things). We could add another new stat but at least for now that
1309 * seems like overkill.
1310 */
1311 if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) {
1312 UDP6_INC_STATS_USER(sock_net(sk),
1313 UDP_MIB_SNDBUFERRORS, is_udplite);
1314 }
1315 return err;
1316
1317do_confirm:
1318 dst_confirm(dst);
1319 if (!(msg->msg_flags&MSG_PROBE) || len)
1320 goto back_from_confirm;
1321 err = 0;
1322 goto out;
1323}
1324
1325void udpv6_destroy_sock(struct sock *sk)
1326{
1327 struct udp_sock *up = udp_sk(sk);
1328 lock_sock(sk);
1329 udp_v6_flush_pending_frames(sk);
1330 release_sock(sk);
1331
1332 if (static_key_false(&udpv6_encap_needed) && up->encap_type) {
1333 void (*encap_destroy)(struct sock *sk);
1334 encap_destroy = ACCESS_ONCE(up->encap_destroy);
1335 if (encap_destroy)
1336 encap_destroy(sk);
1337 }
1338
1339 inet6_destroy_sock(sk);
1340}
1341
1342/*
1343 * Socket option code for UDP
1344 */
1345int udpv6_setsockopt(struct sock *sk, int level, int optname,
1346 char __user *optval, unsigned int optlen)
1347{
1348 if (level == SOL_UDP || level == SOL_UDPLITE)
1349 return udp_lib_setsockopt(sk, level, optname, optval, optlen,
1350 udp_v6_push_pending_frames);
1351 return ipv6_setsockopt(sk, level, optname, optval, optlen);
1352}
1353
1354#ifdef CONFIG_COMPAT
1355int compat_udpv6_setsockopt(struct sock *sk, int level, int optname,
1356 char __user *optval, unsigned int optlen)
1357{
1358 if (level == SOL_UDP || level == SOL_UDPLITE)
1359 return udp_lib_setsockopt(sk, level, optname, optval, optlen,
1360 udp_v6_push_pending_frames);
1361 return compat_ipv6_setsockopt(sk, level, optname, optval, optlen);
1362}
1363#endif
1364
1365int udpv6_getsockopt(struct sock *sk, int level, int optname,
1366 char __user *optval, int __user *optlen)
1367{
1368 if (level == SOL_UDP || level == SOL_UDPLITE)
1369 return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1370 return ipv6_getsockopt(sk, level, optname, optval, optlen);
1371}
1372
1373#ifdef CONFIG_COMPAT
1374int compat_udpv6_getsockopt(struct sock *sk, int level, int optname,
1375 char __user *optval, int __user *optlen)
1376{
1377 if (level == SOL_UDP || level == SOL_UDPLITE)
1378 return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1379 return compat_ipv6_getsockopt(sk, level, optname, optval, optlen);
1380}
1381#endif
1382
1383static const struct inet6_protocol udpv6_protocol = {
1384 .handler = udpv6_rcv,
1385 .err_handler = udpv6_err,
1386 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1387};
1388
1389/* ------------------------------------------------------------------------ */
1390#ifdef CONFIG_PROC_FS
1391int udp6_seq_show(struct seq_file *seq, void *v)
1392{
1393 if (v == SEQ_START_TOKEN) {
1394 seq_puts(seq, IPV6_SEQ_DGRAM_HEADER);
1395 } else {
1396 int bucket = ((struct udp_iter_state *)seq->private)->bucket;
1397 struct inet_sock *inet = inet_sk(v);
1398 __u16 srcp = ntohs(inet->inet_sport);
1399 __u16 destp = ntohs(inet->inet_dport);
1400 ip6_dgram_sock_seq_show(seq, v, srcp, destp, bucket);
1401 }
1402 return 0;
1403}
1404
1405static const struct file_operations udp6_afinfo_seq_fops = {
1406 .owner = THIS_MODULE,
1407 .open = udp_seq_open,
1408 .read = seq_read,
1409 .llseek = seq_lseek,
1410 .release = seq_release_net
1411};
1412
1413static struct udp_seq_afinfo udp6_seq_afinfo = {
1414 .name = "udp6",
1415 .family = AF_INET6,
1416 .udp_table = &udp_table,
1417 .seq_fops = &udp6_afinfo_seq_fops,
1418 .seq_ops = {
1419 .show = udp6_seq_show,
1420 },
1421};
1422
1423int __net_init udp6_proc_init(struct net *net)
1424{
1425 return udp_proc_register(net, &udp6_seq_afinfo);
1426}
1427
1428void udp6_proc_exit(struct net *net) {
1429 udp_proc_unregister(net, &udp6_seq_afinfo);
1430}
1431#endif /* CONFIG_PROC_FS */
1432
1433void udp_v6_clear_sk(struct sock *sk, int size)
1434{
1435 struct inet_sock *inet = inet_sk(sk);
1436
1437 /* we do not want to clear pinet6 field, because of RCU lookups */
1438 sk_prot_clear_portaddr_nulls(sk, offsetof(struct inet_sock, pinet6));
1439
1440 size -= offsetof(struct inet_sock, pinet6) + sizeof(inet->pinet6);
1441 memset(&inet->pinet6 + 1, 0, size);
1442}
1443
1444/* ------------------------------------------------------------------------ */
1445
1446struct proto udpv6_prot = {
1447 .name = "UDPv6",
1448 .owner = THIS_MODULE,
1449 .close = udp_lib_close,
1450 .connect = ip6_datagram_connect,
1451 .disconnect = udp_disconnect,
1452 .ioctl = udp_ioctl,
1453 .destroy = udpv6_destroy_sock,
1454 .setsockopt = udpv6_setsockopt,
1455 .getsockopt = udpv6_getsockopt,
1456 .sendmsg = udpv6_sendmsg,
1457 .recvmsg = udpv6_recvmsg,
1458 .backlog_rcv = __udpv6_queue_rcv_skb,
1459 .hash = udp_lib_hash,
1460 .unhash = udp_lib_unhash,
1461 .rehash = udp_v6_rehash,
1462 .get_port = udp_v6_get_port,
1463 .memory_allocated = &udp_memory_allocated,
1464 .sysctl_mem = sysctl_udp_mem,
1465 .sysctl_wmem = &sysctl_udp_wmem_min,
1466 .sysctl_rmem = &sysctl_udp_rmem_min,
1467 .obj_size = sizeof(struct udp6_sock),
1468 .slab_flags = SLAB_DESTROY_BY_RCU,
1469 .h.udp_table = &udp_table,
1470#ifdef CONFIG_COMPAT
1471 .compat_setsockopt = compat_udpv6_setsockopt,
1472 .compat_getsockopt = compat_udpv6_getsockopt,
1473#endif
1474 .clear_sk = udp_v6_clear_sk,
1475};
1476
1477static struct inet_protosw udpv6_protosw = {
1478 .type = SOCK_DGRAM,
1479 .protocol = IPPROTO_UDP,
1480 .prot = &udpv6_prot,
1481 .ops = &inet6_dgram_ops,
1482 .no_check = UDP_CSUM_DEFAULT,
1483 .flags = INET_PROTOSW_PERMANENT,
1484};
1485
1486
1487int __init udpv6_init(void)
1488{
1489 int ret;
1490
1491 ret = inet6_add_protocol(&udpv6_protocol, IPPROTO_UDP);
1492 if (ret)
1493 goto out;
1494
1495 ret = inet6_register_protosw(&udpv6_protosw);
1496 if (ret)
1497 goto out_udpv6_protocol;
1498out:
1499 return ret;
1500
1501out_udpv6_protocol:
1502 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1503 goto out;
1504}
1505
1506void udpv6_exit(void)
1507{
1508 inet6_unregister_protosw(&udpv6_protosw);
1509 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1510}
1/*
2 * UDP over IPv6
3 * Linux INET6 implementation
4 *
5 * Authors:
6 * Pedro Roque <roque@di.fc.ul.pt>
7 *
8 * Based on linux/ipv4/udp.c
9 *
10 * Fixes:
11 * Hideaki YOSHIFUJI : sin6_scope_id support
12 * YOSHIFUJI Hideaki @USAGI and: Support IPV6_V6ONLY socket option, which
13 * Alexey Kuznetsov allow both IPv4 and IPv6 sockets to bind
14 * a single port at the same time.
15 * Kazunori MIYAZAWA @USAGI: change process style to use ip6_append_data
16 * YOSHIFUJI Hideaki @USAGI: convert /proc/net/udp6 to seq_file.
17 *
18 * This program is free software; you can redistribute it and/or
19 * modify it under the terms of the GNU General Public License
20 * as published by the Free Software Foundation; either version
21 * 2 of the License, or (at your option) any later version.
22 */
23
24#include <linux/errno.h>
25#include <linux/types.h>
26#include <linux/socket.h>
27#include <linux/sockios.h>
28#include <linux/net.h>
29#include <linux/in6.h>
30#include <linux/netdevice.h>
31#include <linux/if_arp.h>
32#include <linux/ipv6.h>
33#include <linux/icmpv6.h>
34#include <linux/init.h>
35#include <linux/module.h>
36#include <linux/skbuff.h>
37#include <linux/slab.h>
38#include <asm/uaccess.h>
39
40#include <net/ndisc.h>
41#include <net/protocol.h>
42#include <net/transp_v6.h>
43#include <net/ip6_route.h>
44#include <net/raw.h>
45#include <net/tcp_states.h>
46#include <net/ip6_checksum.h>
47#include <net/xfrm.h>
48
49#include <linux/proc_fs.h>
50#include <linux/seq_file.h>
51#include "udp_impl.h"
52
53int ipv6_rcv_saddr_equal(const struct sock *sk, const struct sock *sk2)
54{
55 const struct in6_addr *sk_rcv_saddr6 = &inet6_sk(sk)->rcv_saddr;
56 const struct in6_addr *sk2_rcv_saddr6 = inet6_rcv_saddr(sk2);
57 __be32 sk1_rcv_saddr = sk_rcv_saddr(sk);
58 __be32 sk2_rcv_saddr = sk_rcv_saddr(sk2);
59 int sk_ipv6only = ipv6_only_sock(sk);
60 int sk2_ipv6only = inet_v6_ipv6only(sk2);
61 int addr_type = ipv6_addr_type(sk_rcv_saddr6);
62 int addr_type2 = sk2_rcv_saddr6 ? ipv6_addr_type(sk2_rcv_saddr6) : IPV6_ADDR_MAPPED;
63
64 /* if both are mapped, treat as IPv4 */
65 if (addr_type == IPV6_ADDR_MAPPED && addr_type2 == IPV6_ADDR_MAPPED)
66 return (!sk2_ipv6only &&
67 (!sk1_rcv_saddr || !sk2_rcv_saddr ||
68 sk1_rcv_saddr == sk2_rcv_saddr));
69
70 if (addr_type2 == IPV6_ADDR_ANY &&
71 !(sk2_ipv6only && addr_type == IPV6_ADDR_MAPPED))
72 return 1;
73
74 if (addr_type == IPV6_ADDR_ANY &&
75 !(sk_ipv6only && addr_type2 == IPV6_ADDR_MAPPED))
76 return 1;
77
78 if (sk2_rcv_saddr6 &&
79 ipv6_addr_equal(sk_rcv_saddr6, sk2_rcv_saddr6))
80 return 1;
81
82 return 0;
83}
84
85static unsigned int udp6_portaddr_hash(struct net *net,
86 const struct in6_addr *addr6,
87 unsigned int port)
88{
89 unsigned int hash, mix = net_hash_mix(net);
90
91 if (ipv6_addr_any(addr6))
92 hash = jhash_1word(0, mix);
93 else if (ipv6_addr_v4mapped(addr6))
94 hash = jhash_1word((__force u32)addr6->s6_addr32[3], mix);
95 else
96 hash = jhash2((__force u32 *)addr6->s6_addr32, 4, mix);
97
98 return hash ^ port;
99}
100
101
102int udp_v6_get_port(struct sock *sk, unsigned short snum)
103{
104 unsigned int hash2_nulladdr =
105 udp6_portaddr_hash(sock_net(sk), &in6addr_any, snum);
106 unsigned int hash2_partial =
107 udp6_portaddr_hash(sock_net(sk), &inet6_sk(sk)->rcv_saddr, 0);
108
109 /* precompute partial secondary hash */
110 udp_sk(sk)->udp_portaddr_hash = hash2_partial;
111 return udp_lib_get_port(sk, snum, ipv6_rcv_saddr_equal, hash2_nulladdr);
112}
113
114static void udp_v6_rehash(struct sock *sk)
115{
116 u16 new_hash = udp6_portaddr_hash(sock_net(sk),
117 &inet6_sk(sk)->rcv_saddr,
118 inet_sk(sk)->inet_num);
119
120 udp_lib_rehash(sk, new_hash);
121}
122
123static inline int compute_score(struct sock *sk, struct net *net,
124 unsigned short hnum,
125 const struct in6_addr *saddr, __be16 sport,
126 const struct in6_addr *daddr, __be16 dport,
127 int dif)
128{
129 int score = -1;
130
131 if (net_eq(sock_net(sk), net) && udp_sk(sk)->udp_port_hash == hnum &&
132 sk->sk_family == PF_INET6) {
133 struct ipv6_pinfo *np = inet6_sk(sk);
134 struct inet_sock *inet = inet_sk(sk);
135
136 score = 0;
137 if (inet->inet_dport) {
138 if (inet->inet_dport != sport)
139 return -1;
140 score++;
141 }
142 if (!ipv6_addr_any(&np->rcv_saddr)) {
143 if (!ipv6_addr_equal(&np->rcv_saddr, daddr))
144 return -1;
145 score++;
146 }
147 if (!ipv6_addr_any(&np->daddr)) {
148 if (!ipv6_addr_equal(&np->daddr, saddr))
149 return -1;
150 score++;
151 }
152 if (sk->sk_bound_dev_if) {
153 if (sk->sk_bound_dev_if != dif)
154 return -1;
155 score++;
156 }
157 }
158 return score;
159}
160
161#define SCORE2_MAX (1 + 1 + 1)
162static inline int compute_score2(struct sock *sk, struct net *net,
163 const struct in6_addr *saddr, __be16 sport,
164 const struct in6_addr *daddr, unsigned short hnum,
165 int dif)
166{
167 int score = -1;
168
169 if (net_eq(sock_net(sk), net) && udp_sk(sk)->udp_port_hash == hnum &&
170 sk->sk_family == PF_INET6) {
171 struct ipv6_pinfo *np = inet6_sk(sk);
172 struct inet_sock *inet = inet_sk(sk);
173
174 if (!ipv6_addr_equal(&np->rcv_saddr, daddr))
175 return -1;
176 score = 0;
177 if (inet->inet_dport) {
178 if (inet->inet_dport != sport)
179 return -1;
180 score++;
181 }
182 if (!ipv6_addr_any(&np->daddr)) {
183 if (!ipv6_addr_equal(&np->daddr, saddr))
184 return -1;
185 score++;
186 }
187 if (sk->sk_bound_dev_if) {
188 if (sk->sk_bound_dev_if != dif)
189 return -1;
190 score++;
191 }
192 }
193 return score;
194}
195
196
197/* called with read_rcu_lock() */
198static struct sock *udp6_lib_lookup2(struct net *net,
199 const struct in6_addr *saddr, __be16 sport,
200 const struct in6_addr *daddr, unsigned int hnum, int dif,
201 struct udp_hslot *hslot2, unsigned int slot2)
202{
203 struct sock *sk, *result;
204 struct hlist_nulls_node *node;
205 int score, badness;
206
207begin:
208 result = NULL;
209 badness = -1;
210 udp_portaddr_for_each_entry_rcu(sk, node, &hslot2->head) {
211 score = compute_score2(sk, net, saddr, sport,
212 daddr, hnum, dif);
213 if (score > badness) {
214 result = sk;
215 badness = score;
216 if (score == SCORE2_MAX)
217 goto exact_match;
218 }
219 }
220 /*
221 * if the nulls value we got at the end of this lookup is
222 * not the expected one, we must restart lookup.
223 * We probably met an item that was moved to another chain.
224 */
225 if (get_nulls_value(node) != slot2)
226 goto begin;
227
228 if (result) {
229exact_match:
230 if (unlikely(!atomic_inc_not_zero_hint(&result->sk_refcnt, 2)))
231 result = NULL;
232 else if (unlikely(compute_score2(result, net, saddr, sport,
233 daddr, hnum, dif) < badness)) {
234 sock_put(result);
235 goto begin;
236 }
237 }
238 return result;
239}
240
241struct sock *__udp6_lib_lookup(struct net *net,
242 const struct in6_addr *saddr, __be16 sport,
243 const struct in6_addr *daddr, __be16 dport,
244 int dif, struct udp_table *udptable)
245{
246 struct sock *sk, *result;
247 struct hlist_nulls_node *node;
248 unsigned short hnum = ntohs(dport);
249 unsigned int hash2, slot2, slot = udp_hashfn(net, hnum, udptable->mask);
250 struct udp_hslot *hslot2, *hslot = &udptable->hash[slot];
251 int score, badness;
252
253 rcu_read_lock();
254 if (hslot->count > 10) {
255 hash2 = udp6_portaddr_hash(net, daddr, hnum);
256 slot2 = hash2 & udptable->mask;
257 hslot2 = &udptable->hash2[slot2];
258 if (hslot->count < hslot2->count)
259 goto begin;
260
261 result = udp6_lib_lookup2(net, saddr, sport,
262 daddr, hnum, dif,
263 hslot2, slot2);
264 if (!result) {
265 hash2 = udp6_portaddr_hash(net, &in6addr_any, hnum);
266 slot2 = hash2 & udptable->mask;
267 hslot2 = &udptable->hash2[slot2];
268 if (hslot->count < hslot2->count)
269 goto begin;
270
271 result = udp6_lib_lookup2(net, saddr, sport,
272 &in6addr_any, hnum, dif,
273 hslot2, slot2);
274 }
275 rcu_read_unlock();
276 return result;
277 }
278begin:
279 result = NULL;
280 badness = -1;
281 sk_nulls_for_each_rcu(sk, node, &hslot->head) {
282 score = compute_score(sk, net, hnum, saddr, sport, daddr, dport, dif);
283 if (score > badness) {
284 result = sk;
285 badness = score;
286 }
287 }
288 /*
289 * if the nulls value we got at the end of this lookup is
290 * not the expected one, we must restart lookup.
291 * We probably met an item that was moved to another chain.
292 */
293 if (get_nulls_value(node) != slot)
294 goto begin;
295
296 if (result) {
297 if (unlikely(!atomic_inc_not_zero_hint(&result->sk_refcnt, 2)))
298 result = NULL;
299 else if (unlikely(compute_score(result, net, hnum, saddr, sport,
300 daddr, dport, dif) < badness)) {
301 sock_put(result);
302 goto begin;
303 }
304 }
305 rcu_read_unlock();
306 return result;
307}
308EXPORT_SYMBOL_GPL(__udp6_lib_lookup);
309
310static struct sock *__udp6_lib_lookup_skb(struct sk_buff *skb,
311 __be16 sport, __be16 dport,
312 struct udp_table *udptable)
313{
314 struct sock *sk;
315 const struct ipv6hdr *iph = ipv6_hdr(skb);
316
317 if (unlikely(sk = skb_steal_sock(skb)))
318 return sk;
319 return __udp6_lib_lookup(dev_net(skb_dst(skb)->dev), &iph->saddr, sport,
320 &iph->daddr, dport, inet6_iif(skb),
321 udptable);
322}
323
324struct sock *udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport,
325 const struct in6_addr *daddr, __be16 dport, int dif)
326{
327 return __udp6_lib_lookup(net, saddr, sport, daddr, dport, dif, &udp_table);
328}
329EXPORT_SYMBOL_GPL(udp6_lib_lookup);
330
331
332/*
333 * This should be easy, if there is something there we
334 * return it, otherwise we block.
335 */
336
337int udpv6_recvmsg(struct kiocb *iocb, struct sock *sk,
338 struct msghdr *msg, size_t len,
339 int noblock, int flags, int *addr_len)
340{
341 struct ipv6_pinfo *np = inet6_sk(sk);
342 struct inet_sock *inet = inet_sk(sk);
343 struct sk_buff *skb;
344 unsigned int ulen, copied;
345 int peeked, off = 0;
346 int err;
347 int is_udplite = IS_UDPLITE(sk);
348 int is_udp4;
349 bool slow;
350
351 if (addr_len)
352 *addr_len = sizeof(struct sockaddr_in6);
353
354 if (flags & MSG_ERRQUEUE)
355 return ipv6_recv_error(sk, msg, len);
356
357 if (np->rxpmtu && np->rxopt.bits.rxpmtu)
358 return ipv6_recv_rxpmtu(sk, msg, len);
359
360try_again:
361 skb = __skb_recv_datagram(sk, flags | (noblock ? MSG_DONTWAIT : 0),
362 &peeked, &off, &err);
363 if (!skb)
364 goto out;
365
366 ulen = skb->len - sizeof(struct udphdr);
367 copied = len;
368 if (copied > ulen)
369 copied = ulen;
370 else if (copied < ulen)
371 msg->msg_flags |= MSG_TRUNC;
372
373 is_udp4 = (skb->protocol == htons(ETH_P_IP));
374
375 /*
376 * If checksum is needed at all, try to do it while copying the
377 * data. If the data is truncated, or if we only want a partial
378 * coverage checksum (UDP-Lite), do it before the copy.
379 */
380
381 if (copied < ulen || UDP_SKB_CB(skb)->partial_cov) {
382 if (udp_lib_checksum_complete(skb))
383 goto csum_copy_err;
384 }
385
386 if (skb_csum_unnecessary(skb))
387 err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr),
388 msg->msg_iov, copied );
389 else {
390 err = skb_copy_and_csum_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov);
391 if (err == -EINVAL)
392 goto csum_copy_err;
393 }
394 if (err)
395 goto out_free;
396
397 if (!peeked) {
398 if (is_udp4)
399 UDP_INC_STATS_USER(sock_net(sk),
400 UDP_MIB_INDATAGRAMS, is_udplite);
401 else
402 UDP6_INC_STATS_USER(sock_net(sk),
403 UDP_MIB_INDATAGRAMS, is_udplite);
404 }
405
406 sock_recv_ts_and_drops(msg, sk, skb);
407
408 /* Copy the address. */
409 if (msg->msg_name) {
410 struct sockaddr_in6 *sin6;
411
412 sin6 = (struct sockaddr_in6 *) msg->msg_name;
413 sin6->sin6_family = AF_INET6;
414 sin6->sin6_port = udp_hdr(skb)->source;
415 sin6->sin6_flowinfo = 0;
416 sin6->sin6_scope_id = 0;
417
418 if (is_udp4)
419 ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
420 &sin6->sin6_addr);
421 else {
422 sin6->sin6_addr = ipv6_hdr(skb)->saddr;
423 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
424 sin6->sin6_scope_id = IP6CB(skb)->iif;
425 }
426
427 }
428 if (is_udp4) {
429 if (inet->cmsg_flags)
430 ip_cmsg_recv(msg, skb);
431 } else {
432 if (np->rxopt.all)
433 datagram_recv_ctl(sk, msg, skb);
434 }
435
436 err = copied;
437 if (flags & MSG_TRUNC)
438 err = ulen;
439
440out_free:
441 skb_free_datagram_locked(sk, skb);
442out:
443 return err;
444
445csum_copy_err:
446 slow = lock_sock_fast(sk);
447 if (!skb_kill_datagram(sk, skb, flags)) {
448 if (is_udp4)
449 UDP_INC_STATS_USER(sock_net(sk),
450 UDP_MIB_INERRORS, is_udplite);
451 else
452 UDP6_INC_STATS_USER(sock_net(sk),
453 UDP_MIB_INERRORS, is_udplite);
454 }
455 unlock_sock_fast(sk, slow);
456
457 if (noblock)
458 return -EAGAIN;
459
460 /* starting over for a new packet */
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 err;
476
477 sk = __udp6_lib_lookup(dev_net(skb->dev), daddr, uh->dest,
478 saddr, uh->source, inet6_iif(skb), udptable);
479 if (sk == NULL)
480 return;
481
482 np = inet6_sk(sk);
483
484 if (!icmpv6_err_convert(type, code, &err) && !np->recverr)
485 goto out;
486
487 if (sk->sk_state != TCP_ESTABLISHED && !np->recverr)
488 goto out;
489
490 if (np->recverr)
491 ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1));
492
493 sk->sk_err = err;
494 sk->sk_error_report(sk);
495out:
496 sock_put(sk);
497}
498
499static int __udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
500{
501 int rc;
502
503 if (!ipv6_addr_any(&inet6_sk(sk)->daddr))
504 sock_rps_save_rxhash(sk, skb);
505
506 rc = sock_queue_rcv_skb(sk, skb);
507 if (rc < 0) {
508 int is_udplite = IS_UDPLITE(sk);
509
510 /* Note that an ENOMEM error is charged twice */
511 if (rc == -ENOMEM)
512 UDP6_INC_STATS_BH(sock_net(sk),
513 UDP_MIB_RCVBUFERRORS, is_udplite);
514 UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
515 kfree_skb(skb);
516 return -1;
517 }
518 return 0;
519}
520
521static __inline__ void udpv6_err(struct sk_buff *skb,
522 struct inet6_skb_parm *opt, u8 type,
523 u8 code, int offset, __be32 info )
524{
525 __udp6_lib_err(skb, opt, type, code, offset, info, &udp_table);
526}
527
528static struct static_key udpv6_encap_needed __read_mostly;
529void udpv6_encap_enable(void)
530{
531 if (!static_key_enabled(&udpv6_encap_needed))
532 static_key_slow_inc(&udpv6_encap_needed);
533}
534EXPORT_SYMBOL(udpv6_encap_enable);
535
536int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
537{
538 struct udp_sock *up = udp_sk(sk);
539 int rc;
540 int is_udplite = IS_UDPLITE(sk);
541
542 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
543 goto drop;
544
545 if (static_key_false(&udpv6_encap_needed) && up->encap_type) {
546 int (*encap_rcv)(struct sock *sk, struct sk_buff *skb);
547
548 /*
549 * This is an encapsulation socket so pass the skb to
550 * the socket's udp_encap_rcv() hook. Otherwise, just
551 * fall through and pass this up the UDP socket.
552 * up->encap_rcv() returns the following value:
553 * =0 if skb was successfully passed to the encap
554 * handler or was discarded by it.
555 * >0 if skb should be passed on to UDP.
556 * <0 if skb should be resubmitted as proto -N
557 */
558
559 /* if we're overly short, let UDP handle it */
560 encap_rcv = ACCESS_ONCE(up->encap_rcv);
561 if (skb->len > sizeof(struct udphdr) && encap_rcv != NULL) {
562 int ret;
563
564 ret = encap_rcv(sk, skb);
565 if (ret <= 0) {
566 UDP_INC_STATS_BH(sock_net(sk),
567 UDP_MIB_INDATAGRAMS,
568 is_udplite);
569 return -ret;
570 }
571 }
572
573 /* FALLTHROUGH -- it's a UDP Packet */
574 }
575
576 /*
577 * UDP-Lite specific tests, ignored on UDP sockets (see net/ipv4/udp.c).
578 */
579 if ((is_udplite & UDPLITE_RECV_CC) && UDP_SKB_CB(skb)->partial_cov) {
580
581 if (up->pcrlen == 0) { /* full coverage was set */
582 LIMIT_NETDEBUG(KERN_WARNING "UDPLITE6: partial coverage"
583 " %d while full coverage %d requested\n",
584 UDP_SKB_CB(skb)->cscov, skb->len);
585 goto drop;
586 }
587 if (UDP_SKB_CB(skb)->cscov < up->pcrlen) {
588 LIMIT_NETDEBUG(KERN_WARNING "UDPLITE6: coverage %d "
589 "too small, need min %d\n",
590 UDP_SKB_CB(skb)->cscov, up->pcrlen);
591 goto drop;
592 }
593 }
594
595 if (rcu_access_pointer(sk->sk_filter)) {
596 if (udp_lib_checksum_complete(skb))
597 goto drop;
598 }
599
600 if (sk_rcvqueues_full(sk, skb, sk->sk_rcvbuf))
601 goto drop;
602
603 skb_dst_drop(skb);
604
605 bh_lock_sock(sk);
606 rc = 0;
607 if (!sock_owned_by_user(sk))
608 rc = __udpv6_queue_rcv_skb(sk, skb);
609 else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) {
610 bh_unlock_sock(sk);
611 goto drop;
612 }
613 bh_unlock_sock(sk);
614
615 return rc;
616drop:
617 UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
618 atomic_inc(&sk->sk_drops);
619 kfree_skb(skb);
620 return -1;
621}
622
623static struct sock *udp_v6_mcast_next(struct net *net, struct sock *sk,
624 __be16 loc_port, const struct in6_addr *loc_addr,
625 __be16 rmt_port, const struct in6_addr *rmt_addr,
626 int dif)
627{
628 struct hlist_nulls_node *node;
629 struct sock *s = sk;
630 unsigned short num = ntohs(loc_port);
631
632 sk_nulls_for_each_from(s, node) {
633 struct inet_sock *inet = inet_sk(s);
634
635 if (!net_eq(sock_net(s), net))
636 continue;
637
638 if (udp_sk(s)->udp_port_hash == num &&
639 s->sk_family == PF_INET6) {
640 struct ipv6_pinfo *np = inet6_sk(s);
641 if (inet->inet_dport) {
642 if (inet->inet_dport != rmt_port)
643 continue;
644 }
645 if (!ipv6_addr_any(&np->daddr) &&
646 !ipv6_addr_equal(&np->daddr, rmt_addr))
647 continue;
648
649 if (s->sk_bound_dev_if && s->sk_bound_dev_if != dif)
650 continue;
651
652 if (!ipv6_addr_any(&np->rcv_saddr)) {
653 if (!ipv6_addr_equal(&np->rcv_saddr, loc_addr))
654 continue;
655 }
656 if (!inet6_mc_check(s, loc_addr, rmt_addr))
657 continue;
658 return s;
659 }
660 }
661 return NULL;
662}
663
664static void flush_stack(struct sock **stack, unsigned int count,
665 struct sk_buff *skb, unsigned int final)
666{
667 struct sk_buff *skb1 = NULL;
668 struct sock *sk;
669 unsigned int i;
670
671 for (i = 0; i < count; i++) {
672 sk = stack[i];
673 if (likely(skb1 == NULL))
674 skb1 = (i == final) ? skb : skb_clone(skb, GFP_ATOMIC);
675 if (!skb1) {
676 atomic_inc(&sk->sk_drops);
677 UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_RCVBUFERRORS,
678 IS_UDPLITE(sk));
679 UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS,
680 IS_UDPLITE(sk));
681 }
682
683 if (skb1 && udpv6_queue_rcv_skb(sk, skb1) <= 0)
684 skb1 = NULL;
685 }
686 if (unlikely(skb1))
687 kfree_skb(skb1);
688}
689/*
690 * Note: called only from the BH handler context,
691 * so we don't need to lock the hashes.
692 */
693static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
694 const struct in6_addr *saddr, const struct in6_addr *daddr,
695 struct udp_table *udptable)
696{
697 struct sock *sk, *stack[256 / sizeof(struct sock *)];
698 const struct udphdr *uh = udp_hdr(skb);
699 struct udp_hslot *hslot = udp_hashslot(udptable, net, ntohs(uh->dest));
700 int dif;
701 unsigned int i, count = 0;
702
703 spin_lock(&hslot->lock);
704 sk = sk_nulls_head(&hslot->head);
705 dif = inet6_iif(skb);
706 sk = udp_v6_mcast_next(net, sk, uh->dest, daddr, uh->source, saddr, dif);
707 while (sk) {
708 stack[count++] = sk;
709 sk = udp_v6_mcast_next(net, sk_nulls_next(sk), uh->dest, daddr,
710 uh->source, saddr, dif);
711 if (unlikely(count == ARRAY_SIZE(stack))) {
712 if (!sk)
713 break;
714 flush_stack(stack, count, skb, ~0);
715 count = 0;
716 }
717 }
718 /*
719 * before releasing the lock, we must take reference on sockets
720 */
721 for (i = 0; i < count; i++)
722 sock_hold(stack[i]);
723
724 spin_unlock(&hslot->lock);
725
726 if (count) {
727 flush_stack(stack, count, skb, count - 1);
728
729 for (i = 0; i < count; i++)
730 sock_put(stack[i]);
731 } else {
732 kfree_skb(skb);
733 }
734 return 0;
735}
736
737static inline int udp6_csum_init(struct sk_buff *skb, struct udphdr *uh,
738 int proto)
739{
740 int err;
741
742 UDP_SKB_CB(skb)->partial_cov = 0;
743 UDP_SKB_CB(skb)->cscov = skb->len;
744
745 if (proto == IPPROTO_UDPLITE) {
746 err = udplite_checksum_init(skb, uh);
747 if (err)
748 return err;
749 }
750
751 if (uh->check == 0) {
752 /* RFC 2460 section 8.1 says that we SHOULD log
753 this error. Well, it is reasonable.
754 */
755 LIMIT_NETDEBUG(KERN_INFO "IPv6: udp checksum is 0\n");
756 return 1;
757 }
758 if (skb->ip_summed == CHECKSUM_COMPLETE &&
759 !csum_ipv6_magic(&ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
760 skb->len, proto, skb->csum))
761 skb->ip_summed = CHECKSUM_UNNECESSARY;
762
763 if (!skb_csum_unnecessary(skb))
764 skb->csum = ~csum_unfold(csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
765 &ipv6_hdr(skb)->daddr,
766 skb->len, proto, 0));
767
768 return 0;
769}
770
771int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
772 int proto)
773{
774 struct net *net = dev_net(skb->dev);
775 struct sock *sk;
776 struct udphdr *uh;
777 const struct in6_addr *saddr, *daddr;
778 u32 ulen = 0;
779
780 if (!pskb_may_pull(skb, sizeof(struct udphdr)))
781 goto discard;
782
783 saddr = &ipv6_hdr(skb)->saddr;
784 daddr = &ipv6_hdr(skb)->daddr;
785 uh = udp_hdr(skb);
786
787 ulen = ntohs(uh->len);
788 if (ulen > skb->len)
789 goto short_packet;
790
791 if (proto == IPPROTO_UDP) {
792 /* UDP validates ulen. */
793
794 /* Check for jumbo payload */
795 if (ulen == 0)
796 ulen = skb->len;
797
798 if (ulen < sizeof(*uh))
799 goto short_packet;
800
801 if (ulen < skb->len) {
802 if (pskb_trim_rcsum(skb, ulen))
803 goto short_packet;
804 saddr = &ipv6_hdr(skb)->saddr;
805 daddr = &ipv6_hdr(skb)->daddr;
806 uh = udp_hdr(skb);
807 }
808 }
809
810 if (udp6_csum_init(skb, uh, proto))
811 goto discard;
812
813 /*
814 * Multicast receive code
815 */
816 if (ipv6_addr_is_multicast(daddr))
817 return __udp6_lib_mcast_deliver(net, skb,
818 saddr, daddr, udptable);
819
820 /* Unicast */
821
822 /*
823 * check socket cache ... must talk to Alan about his plans
824 * for sock caches... i'll skip this for now.
825 */
826 sk = __udp6_lib_lookup_skb(skb, uh->source, uh->dest, udptable);
827 if (sk != NULL) {
828 int ret = udpv6_queue_rcv_skb(sk, skb);
829 sock_put(sk);
830
831 /* a return value > 0 means to resubmit the input, but
832 * it wants the return to be -protocol, or 0
833 */
834 if (ret > 0)
835 return -ret;
836
837 return 0;
838 }
839
840 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
841 goto discard;
842
843 if (udp_lib_checksum_complete(skb))
844 goto discard;
845
846 UDP6_INC_STATS_BH(net, UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE);
847 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
848
849 kfree_skb(skb);
850 return 0;
851
852short_packet:
853 LIMIT_NETDEBUG(KERN_DEBUG "UDP%sv6: short packet: From [%pI6c]:%u %d/%d to [%pI6c]:%u\n",
854 proto == IPPROTO_UDPLITE ? "-Lite" : "",
855 saddr,
856 ntohs(uh->source),
857 ulen,
858 skb->len,
859 daddr,
860 ntohs(uh->dest));
861
862discard:
863 UDP6_INC_STATS_BH(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE);
864 kfree_skb(skb);
865 return 0;
866}
867
868static __inline__ int udpv6_rcv(struct sk_buff *skb)
869{
870 return __udp6_lib_rcv(skb, &udp_table, IPPROTO_UDP);
871}
872
873/*
874 * Throw away all pending data and cancel the corking. Socket is locked.
875 */
876static void udp_v6_flush_pending_frames(struct sock *sk)
877{
878 struct udp_sock *up = udp_sk(sk);
879
880 if (up->pending == AF_INET)
881 udp_flush_pending_frames(sk);
882 else if (up->pending) {
883 up->len = 0;
884 up->pending = 0;
885 ip6_flush_pending_frames(sk);
886 }
887}
888
889/**
890 * udp6_hwcsum_outgoing - handle outgoing HW checksumming
891 * @sk: socket we are sending on
892 * @skb: sk_buff containing the filled-in UDP header
893 * (checksum field must be zeroed out)
894 */
895static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb,
896 const struct in6_addr *saddr,
897 const struct in6_addr *daddr, int len)
898{
899 unsigned int offset;
900 struct udphdr *uh = udp_hdr(skb);
901 __wsum csum = 0;
902
903 if (skb_queue_len(&sk->sk_write_queue) == 1) {
904 /* Only one fragment on the socket. */
905 skb->csum_start = skb_transport_header(skb) - skb->head;
906 skb->csum_offset = offsetof(struct udphdr, check);
907 uh->check = ~csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 0);
908 } else {
909 /*
910 * HW-checksum won't work as there are two or more
911 * fragments on the socket so that all csums of sk_buffs
912 * should be together
913 */
914 offset = skb_transport_offset(skb);
915 skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
916
917 skb->ip_summed = CHECKSUM_NONE;
918
919 skb_queue_walk(&sk->sk_write_queue, skb) {
920 csum = csum_add(csum, skb->csum);
921 }
922
923 uh->check = csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP,
924 csum);
925 if (uh->check == 0)
926 uh->check = CSUM_MANGLED_0;
927 }
928}
929
930/*
931 * Sending
932 */
933
934static int udp_v6_push_pending_frames(struct sock *sk)
935{
936 struct sk_buff *skb;
937 struct udphdr *uh;
938 struct udp_sock *up = udp_sk(sk);
939 struct inet_sock *inet = inet_sk(sk);
940 struct flowi6 *fl6 = &inet->cork.fl.u.ip6;
941 int err = 0;
942 int is_udplite = IS_UDPLITE(sk);
943 __wsum csum = 0;
944
945 /* Grab the skbuff where UDP header space exists. */
946 if ((skb = skb_peek(&sk->sk_write_queue)) == NULL)
947 goto out;
948
949 /*
950 * Create a UDP header
951 */
952 uh = udp_hdr(skb);
953 uh->source = fl6->fl6_sport;
954 uh->dest = fl6->fl6_dport;
955 uh->len = htons(up->len);
956 uh->check = 0;
957
958 if (is_udplite)
959 csum = udplite_csum_outgoing(sk, skb);
960 else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */
961 udp6_hwcsum_outgoing(sk, skb, &fl6->saddr, &fl6->daddr,
962 up->len);
963 goto send;
964 } else
965 csum = udp_csum_outgoing(sk, skb);
966
967 /* add protocol-dependent pseudo-header */
968 uh->check = csum_ipv6_magic(&fl6->saddr, &fl6->daddr,
969 up->len, fl6->flowi6_proto, csum);
970 if (uh->check == 0)
971 uh->check = CSUM_MANGLED_0;
972
973send:
974 err = ip6_push_pending_frames(sk);
975 if (err) {
976 if (err == -ENOBUFS && !inet6_sk(sk)->recverr) {
977 UDP6_INC_STATS_USER(sock_net(sk),
978 UDP_MIB_SNDBUFERRORS, is_udplite);
979 err = 0;
980 }
981 } else
982 UDP6_INC_STATS_USER(sock_net(sk),
983 UDP_MIB_OUTDATAGRAMS, is_udplite);
984out:
985 up->len = 0;
986 up->pending = 0;
987 return err;
988}
989
990int udpv6_sendmsg(struct kiocb *iocb, struct sock *sk,
991 struct msghdr *msg, size_t len)
992{
993 struct ipv6_txoptions opt_space;
994 struct udp_sock *up = udp_sk(sk);
995 struct inet_sock *inet = inet_sk(sk);
996 struct ipv6_pinfo *np = inet6_sk(sk);
997 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) msg->msg_name;
998 struct in6_addr *daddr, *final_p, final;
999 struct ipv6_txoptions *opt = NULL;
1000 struct ip6_flowlabel *flowlabel = NULL;
1001 struct flowi6 fl6;
1002 struct dst_entry *dst;
1003 int addr_len = msg->msg_namelen;
1004 int ulen = len;
1005 int hlimit = -1;
1006 int tclass = -1;
1007 int dontfrag = -1;
1008 int corkreq = up->corkflag || msg->msg_flags&MSG_MORE;
1009 int err;
1010 int connected = 0;
1011 int is_udplite = IS_UDPLITE(sk);
1012 int (*getfrag)(void *, char *, int, int, int, struct sk_buff *);
1013
1014 /* destination address check */
1015 if (sin6) {
1016 if (addr_len < offsetof(struct sockaddr, sa_data))
1017 return -EINVAL;
1018
1019 switch (sin6->sin6_family) {
1020 case AF_INET6:
1021 if (addr_len < SIN6_LEN_RFC2133)
1022 return -EINVAL;
1023 daddr = &sin6->sin6_addr;
1024 break;
1025 case AF_INET:
1026 goto do_udp_sendmsg;
1027 case AF_UNSPEC:
1028 msg->msg_name = sin6 = NULL;
1029 msg->msg_namelen = addr_len = 0;
1030 daddr = NULL;
1031 break;
1032 default:
1033 return -EINVAL;
1034 }
1035 } else if (!up->pending) {
1036 if (sk->sk_state != TCP_ESTABLISHED)
1037 return -EDESTADDRREQ;
1038 daddr = &np->daddr;
1039 } else
1040 daddr = NULL;
1041
1042 if (daddr) {
1043 if (ipv6_addr_v4mapped(daddr)) {
1044 struct sockaddr_in sin;
1045 sin.sin_family = AF_INET;
1046 sin.sin_port = sin6 ? sin6->sin6_port : inet->inet_dport;
1047 sin.sin_addr.s_addr = daddr->s6_addr32[3];
1048 msg->msg_name = &sin;
1049 msg->msg_namelen = sizeof(sin);
1050do_udp_sendmsg:
1051 if (__ipv6_only_sock(sk))
1052 return -ENETUNREACH;
1053 return udp_sendmsg(iocb, sk, msg, len);
1054 }
1055 }
1056
1057 if (up->pending == AF_INET)
1058 return udp_sendmsg(iocb, sk, msg, len);
1059
1060 /* Rough check on arithmetic overflow,
1061 better check is made in ip6_append_data().
1062 */
1063 if (len > INT_MAX - sizeof(struct udphdr))
1064 return -EMSGSIZE;
1065
1066 if (up->pending) {
1067 /*
1068 * There are pending frames.
1069 * The socket lock must be held while it's corked.
1070 */
1071 lock_sock(sk);
1072 if (likely(up->pending)) {
1073 if (unlikely(up->pending != AF_INET6)) {
1074 release_sock(sk);
1075 return -EAFNOSUPPORT;
1076 }
1077 dst = NULL;
1078 goto do_append_data;
1079 }
1080 release_sock(sk);
1081 }
1082 ulen += sizeof(struct udphdr);
1083
1084 memset(&fl6, 0, sizeof(fl6));
1085
1086 if (sin6) {
1087 if (sin6->sin6_port == 0)
1088 return -EINVAL;
1089
1090 fl6.fl6_dport = sin6->sin6_port;
1091 daddr = &sin6->sin6_addr;
1092
1093 if (np->sndflow) {
1094 fl6.flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK;
1095 if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) {
1096 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1097 if (flowlabel == NULL)
1098 return -EINVAL;
1099 daddr = &flowlabel->dst;
1100 }
1101 }
1102
1103 /*
1104 * Otherwise it will be difficult to maintain
1105 * sk->sk_dst_cache.
1106 */
1107 if (sk->sk_state == TCP_ESTABLISHED &&
1108 ipv6_addr_equal(daddr, &np->daddr))
1109 daddr = &np->daddr;
1110
1111 if (addr_len >= sizeof(struct sockaddr_in6) &&
1112 sin6->sin6_scope_id &&
1113 ipv6_addr_type(daddr)&IPV6_ADDR_LINKLOCAL)
1114 fl6.flowi6_oif = sin6->sin6_scope_id;
1115 } else {
1116 if (sk->sk_state != TCP_ESTABLISHED)
1117 return -EDESTADDRREQ;
1118
1119 fl6.fl6_dport = inet->inet_dport;
1120 daddr = &np->daddr;
1121 fl6.flowlabel = np->flow_label;
1122 connected = 1;
1123 }
1124
1125 if (!fl6.flowi6_oif)
1126 fl6.flowi6_oif = sk->sk_bound_dev_if;
1127
1128 if (!fl6.flowi6_oif)
1129 fl6.flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;
1130
1131 fl6.flowi6_mark = sk->sk_mark;
1132
1133 if (msg->msg_controllen) {
1134 opt = &opt_space;
1135 memset(opt, 0, sizeof(struct ipv6_txoptions));
1136 opt->tot_len = sizeof(*opt);
1137
1138 err = datagram_send_ctl(sock_net(sk), sk, msg, &fl6, opt,
1139 &hlimit, &tclass, &dontfrag);
1140 if (err < 0) {
1141 fl6_sock_release(flowlabel);
1142 return err;
1143 }
1144 if ((fl6.flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) {
1145 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1146 if (flowlabel == NULL)
1147 return -EINVAL;
1148 }
1149 if (!(opt->opt_nflen|opt->opt_flen))
1150 opt = NULL;
1151 connected = 0;
1152 }
1153 if (opt == NULL)
1154 opt = np->opt;
1155 if (flowlabel)
1156 opt = fl6_merge_options(&opt_space, flowlabel, opt);
1157 opt = ipv6_fixup_options(&opt_space, opt);
1158
1159 fl6.flowi6_proto = sk->sk_protocol;
1160 if (!ipv6_addr_any(daddr))
1161 fl6.daddr = *daddr;
1162 else
1163 fl6.daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */
1164 if (ipv6_addr_any(&fl6.saddr) && !ipv6_addr_any(&np->saddr))
1165 fl6.saddr = np->saddr;
1166 fl6.fl6_sport = inet->inet_sport;
1167
1168 final_p = fl6_update_dst(&fl6, opt, &final);
1169 if (final_p)
1170 connected = 0;
1171
1172 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr)) {
1173 fl6.flowi6_oif = np->mcast_oif;
1174 connected = 0;
1175 } else if (!fl6.flowi6_oif)
1176 fl6.flowi6_oif = np->ucast_oif;
1177
1178 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
1179
1180 dst = ip6_sk_dst_lookup_flow(sk, &fl6, final_p, true);
1181 if (IS_ERR(dst)) {
1182 err = PTR_ERR(dst);
1183 dst = NULL;
1184 goto out;
1185 }
1186
1187 if (hlimit < 0) {
1188 if (ipv6_addr_is_multicast(&fl6.daddr))
1189 hlimit = np->mcast_hops;
1190 else
1191 hlimit = np->hop_limit;
1192 if (hlimit < 0)
1193 hlimit = ip6_dst_hoplimit(dst);
1194 }
1195
1196 if (tclass < 0)
1197 tclass = np->tclass;
1198
1199 if (dontfrag < 0)
1200 dontfrag = np->dontfrag;
1201
1202 if (msg->msg_flags&MSG_CONFIRM)
1203 goto do_confirm;
1204back_from_confirm:
1205
1206 lock_sock(sk);
1207 if (unlikely(up->pending)) {
1208 /* The socket is already corked while preparing it. */
1209 /* ... which is an evident application bug. --ANK */
1210 release_sock(sk);
1211
1212 LIMIT_NETDEBUG(KERN_DEBUG "udp cork app bug 2\n");
1213 err = -EINVAL;
1214 goto out;
1215 }
1216
1217 up->pending = AF_INET6;
1218
1219do_append_data:
1220 up->len += ulen;
1221 getfrag = is_udplite ? udplite_getfrag : ip_generic_getfrag;
1222 err = ip6_append_data(sk, getfrag, msg->msg_iov, ulen,
1223 sizeof(struct udphdr), hlimit, tclass, opt, &fl6,
1224 (struct rt6_info*)dst,
1225 corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags, dontfrag);
1226 if (err)
1227 udp_v6_flush_pending_frames(sk);
1228 else if (!corkreq)
1229 err = udp_v6_push_pending_frames(sk);
1230 else if (unlikely(skb_queue_empty(&sk->sk_write_queue)))
1231 up->pending = 0;
1232
1233 if (dst) {
1234 if (connected) {
1235 ip6_dst_store(sk, dst,
1236 ipv6_addr_equal(&fl6.daddr, &np->daddr) ?
1237 &np->daddr : NULL,
1238#ifdef CONFIG_IPV6_SUBTREES
1239 ipv6_addr_equal(&fl6.saddr, &np->saddr) ?
1240 &np->saddr :
1241#endif
1242 NULL);
1243 } else {
1244 dst_release(dst);
1245 }
1246 dst = NULL;
1247 }
1248
1249 if (err > 0)
1250 err = np->recverr ? net_xmit_errno(err) : 0;
1251 release_sock(sk);
1252out:
1253 dst_release(dst);
1254 fl6_sock_release(flowlabel);
1255 if (!err)
1256 return len;
1257 /*
1258 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space. Reporting
1259 * ENOBUFS might not be good (it's not tunable per se), but otherwise
1260 * we don't have a good statistic (IpOutDiscards but it can be too many
1261 * things). We could add another new stat but at least for now that
1262 * seems like overkill.
1263 */
1264 if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) {
1265 UDP6_INC_STATS_USER(sock_net(sk),
1266 UDP_MIB_SNDBUFERRORS, is_udplite);
1267 }
1268 return err;
1269
1270do_confirm:
1271 dst_confirm(dst);
1272 if (!(msg->msg_flags&MSG_PROBE) || len)
1273 goto back_from_confirm;
1274 err = 0;
1275 goto out;
1276}
1277
1278void udpv6_destroy_sock(struct sock *sk)
1279{
1280 lock_sock(sk);
1281 udp_v6_flush_pending_frames(sk);
1282 release_sock(sk);
1283
1284 inet6_destroy_sock(sk);
1285}
1286
1287/*
1288 * Socket option code for UDP
1289 */
1290int udpv6_setsockopt(struct sock *sk, int level, int optname,
1291 char __user *optval, unsigned int optlen)
1292{
1293 if (level == SOL_UDP || level == SOL_UDPLITE)
1294 return udp_lib_setsockopt(sk, level, optname, optval, optlen,
1295 udp_v6_push_pending_frames);
1296 return ipv6_setsockopt(sk, level, optname, optval, optlen);
1297}
1298
1299#ifdef CONFIG_COMPAT
1300int compat_udpv6_setsockopt(struct sock *sk, int level, int optname,
1301 char __user *optval, unsigned int optlen)
1302{
1303 if (level == SOL_UDP || level == SOL_UDPLITE)
1304 return udp_lib_setsockopt(sk, level, optname, optval, optlen,
1305 udp_v6_push_pending_frames);
1306 return compat_ipv6_setsockopt(sk, level, optname, optval, optlen);
1307}
1308#endif
1309
1310int udpv6_getsockopt(struct sock *sk, int level, int optname,
1311 char __user *optval, int __user *optlen)
1312{
1313 if (level == SOL_UDP || level == SOL_UDPLITE)
1314 return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1315 return ipv6_getsockopt(sk, level, optname, optval, optlen);
1316}
1317
1318#ifdef CONFIG_COMPAT
1319int compat_udpv6_getsockopt(struct sock *sk, int level, int optname,
1320 char __user *optval, int __user *optlen)
1321{
1322 if (level == SOL_UDP || level == SOL_UDPLITE)
1323 return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1324 return compat_ipv6_getsockopt(sk, level, optname, optval, optlen);
1325}
1326#endif
1327
1328static int udp6_ufo_send_check(struct sk_buff *skb)
1329{
1330 const struct ipv6hdr *ipv6h;
1331 struct udphdr *uh;
1332
1333 if (!pskb_may_pull(skb, sizeof(*uh)))
1334 return -EINVAL;
1335
1336 ipv6h = ipv6_hdr(skb);
1337 uh = udp_hdr(skb);
1338
1339 uh->check = ~csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr, skb->len,
1340 IPPROTO_UDP, 0);
1341 skb->csum_start = skb_transport_header(skb) - skb->head;
1342 skb->csum_offset = offsetof(struct udphdr, check);
1343 skb->ip_summed = CHECKSUM_PARTIAL;
1344 return 0;
1345}
1346
1347static struct sk_buff *udp6_ufo_fragment(struct sk_buff *skb,
1348 netdev_features_t features)
1349{
1350 struct sk_buff *segs = ERR_PTR(-EINVAL);
1351 unsigned int mss;
1352 unsigned int unfrag_ip6hlen, unfrag_len;
1353 struct frag_hdr *fptr;
1354 u8 *mac_start, *prevhdr;
1355 u8 nexthdr;
1356 u8 frag_hdr_sz = sizeof(struct frag_hdr);
1357 int offset;
1358 __wsum csum;
1359
1360 mss = skb_shinfo(skb)->gso_size;
1361 if (unlikely(skb->len <= mss))
1362 goto out;
1363
1364 if (skb_gso_ok(skb, features | NETIF_F_GSO_ROBUST)) {
1365 /* Packet is from an untrusted source, reset gso_segs. */
1366 int type = skb_shinfo(skb)->gso_type;
1367
1368 if (unlikely(type & ~(SKB_GSO_UDP | SKB_GSO_DODGY) ||
1369 !(type & (SKB_GSO_UDP))))
1370 goto out;
1371
1372 skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(skb->len, mss);
1373
1374 segs = NULL;
1375 goto out;
1376 }
1377
1378 /* Do software UFO. Complete and fill in the UDP checksum as HW cannot
1379 * do checksum of UDP packets sent as multiple IP fragments.
1380 */
1381 offset = skb_checksum_start_offset(skb);
1382 csum = skb_checksum(skb, offset, skb->len - offset, 0);
1383 offset += skb->csum_offset;
1384 *(__sum16 *)(skb->data + offset) = csum_fold(csum);
1385 skb->ip_summed = CHECKSUM_NONE;
1386
1387 /* Check if there is enough headroom to insert fragment header. */
1388 if ((skb_mac_header(skb) < skb->head + frag_hdr_sz) &&
1389 pskb_expand_head(skb, frag_hdr_sz, 0, GFP_ATOMIC))
1390 goto out;
1391
1392 /* Find the unfragmentable header and shift it left by frag_hdr_sz
1393 * bytes to insert fragment header.
1394 */
1395 unfrag_ip6hlen = ip6_find_1stfragopt(skb, &prevhdr);
1396 nexthdr = *prevhdr;
1397 *prevhdr = NEXTHDR_FRAGMENT;
1398 unfrag_len = skb_network_header(skb) - skb_mac_header(skb) +
1399 unfrag_ip6hlen;
1400 mac_start = skb_mac_header(skb);
1401 memmove(mac_start-frag_hdr_sz, mac_start, unfrag_len);
1402
1403 skb->mac_header -= frag_hdr_sz;
1404 skb->network_header -= frag_hdr_sz;
1405
1406 fptr = (struct frag_hdr *)(skb_network_header(skb) + unfrag_ip6hlen);
1407 fptr->nexthdr = nexthdr;
1408 fptr->reserved = 0;
1409 ipv6_select_ident(fptr, (struct rt6_info *)skb_dst(skb));
1410
1411 /* Fragment the skb. ipv6 header and the remaining fields of the
1412 * fragment header are updated in ipv6_gso_segment()
1413 */
1414 segs = skb_segment(skb, features);
1415
1416out:
1417 return segs;
1418}
1419
1420static const struct inet6_protocol udpv6_protocol = {
1421 .handler = udpv6_rcv,
1422 .err_handler = udpv6_err,
1423 .gso_send_check = udp6_ufo_send_check,
1424 .gso_segment = udp6_ufo_fragment,
1425 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1426};
1427
1428/* ------------------------------------------------------------------------ */
1429#ifdef CONFIG_PROC_FS
1430
1431static void udp6_sock_seq_show(struct seq_file *seq, struct sock *sp, int bucket)
1432{
1433 struct inet_sock *inet = inet_sk(sp);
1434 struct ipv6_pinfo *np = inet6_sk(sp);
1435 const struct in6_addr *dest, *src;
1436 __u16 destp, srcp;
1437
1438 dest = &np->daddr;
1439 src = &np->rcv_saddr;
1440 destp = ntohs(inet->inet_dport);
1441 srcp = ntohs(inet->inet_sport);
1442 seq_printf(seq,
1443 "%5d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1444 "%02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %pK %d\n",
1445 bucket,
1446 src->s6_addr32[0], src->s6_addr32[1],
1447 src->s6_addr32[2], src->s6_addr32[3], srcp,
1448 dest->s6_addr32[0], dest->s6_addr32[1],
1449 dest->s6_addr32[2], dest->s6_addr32[3], destp,
1450 sp->sk_state,
1451 sk_wmem_alloc_get(sp),
1452 sk_rmem_alloc_get(sp),
1453 0, 0L, 0,
1454 sock_i_uid(sp), 0,
1455 sock_i_ino(sp),
1456 atomic_read(&sp->sk_refcnt), sp,
1457 atomic_read(&sp->sk_drops));
1458}
1459
1460int udp6_seq_show(struct seq_file *seq, void *v)
1461{
1462 if (v == SEQ_START_TOKEN)
1463 seq_printf(seq,
1464 " sl "
1465 "local_address "
1466 "remote_address "
1467 "st tx_queue rx_queue tr tm->when retrnsmt"
1468 " uid timeout inode ref pointer drops\n");
1469 else
1470 udp6_sock_seq_show(seq, v, ((struct udp_iter_state *)seq->private)->bucket);
1471 return 0;
1472}
1473
1474static const struct file_operations udp6_afinfo_seq_fops = {
1475 .owner = THIS_MODULE,
1476 .open = udp_seq_open,
1477 .read = seq_read,
1478 .llseek = seq_lseek,
1479 .release = seq_release_net
1480};
1481
1482static struct udp_seq_afinfo udp6_seq_afinfo = {
1483 .name = "udp6",
1484 .family = AF_INET6,
1485 .udp_table = &udp_table,
1486 .seq_fops = &udp6_afinfo_seq_fops,
1487 .seq_ops = {
1488 .show = udp6_seq_show,
1489 },
1490};
1491
1492int __net_init udp6_proc_init(struct net *net)
1493{
1494 return udp_proc_register(net, &udp6_seq_afinfo);
1495}
1496
1497void udp6_proc_exit(struct net *net) {
1498 udp_proc_unregister(net, &udp6_seq_afinfo);
1499}
1500#endif /* CONFIG_PROC_FS */
1501
1502/* ------------------------------------------------------------------------ */
1503
1504struct proto udpv6_prot = {
1505 .name = "UDPv6",
1506 .owner = THIS_MODULE,
1507 .close = udp_lib_close,
1508 .connect = ip6_datagram_connect,
1509 .disconnect = udp_disconnect,
1510 .ioctl = udp_ioctl,
1511 .destroy = udpv6_destroy_sock,
1512 .setsockopt = udpv6_setsockopt,
1513 .getsockopt = udpv6_getsockopt,
1514 .sendmsg = udpv6_sendmsg,
1515 .recvmsg = udpv6_recvmsg,
1516 .backlog_rcv = __udpv6_queue_rcv_skb,
1517 .hash = udp_lib_hash,
1518 .unhash = udp_lib_unhash,
1519 .rehash = udp_v6_rehash,
1520 .get_port = udp_v6_get_port,
1521 .memory_allocated = &udp_memory_allocated,
1522 .sysctl_mem = sysctl_udp_mem,
1523 .sysctl_wmem = &sysctl_udp_wmem_min,
1524 .sysctl_rmem = &sysctl_udp_rmem_min,
1525 .obj_size = sizeof(struct udp6_sock),
1526 .slab_flags = SLAB_DESTROY_BY_RCU,
1527 .h.udp_table = &udp_table,
1528#ifdef CONFIG_COMPAT
1529 .compat_setsockopt = compat_udpv6_setsockopt,
1530 .compat_getsockopt = compat_udpv6_getsockopt,
1531#endif
1532 .clear_sk = sk_prot_clear_portaddr_nulls,
1533};
1534
1535static struct inet_protosw udpv6_protosw = {
1536 .type = SOCK_DGRAM,
1537 .protocol = IPPROTO_UDP,
1538 .prot = &udpv6_prot,
1539 .ops = &inet6_dgram_ops,
1540 .no_check = UDP_CSUM_DEFAULT,
1541 .flags = INET_PROTOSW_PERMANENT,
1542};
1543
1544
1545int __init udpv6_init(void)
1546{
1547 int ret;
1548
1549 ret = inet6_add_protocol(&udpv6_protocol, IPPROTO_UDP);
1550 if (ret)
1551 goto out;
1552
1553 ret = inet6_register_protosw(&udpv6_protosw);
1554 if (ret)
1555 goto out_udpv6_protocol;
1556out:
1557 return ret;
1558
1559out_udpv6_protocol:
1560 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1561 goto out;
1562}
1563
1564void udpv6_exit(void)
1565{
1566 inet6_unregister_protosw(&udpv6_protosw);
1567 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1568}