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1/*
2 * UDP over IPv6
3 * Linux INET6 implementation
4 *
5 * Authors:
6 * Pedro Roque <roque@di.fc.ul.pt>
7 *
8 * Based on linux/ipv4/udp.c
9 *
10 * Fixes:
11 * Hideaki YOSHIFUJI : sin6_scope_id support
12 * YOSHIFUJI Hideaki @USAGI and: Support IPV6_V6ONLY socket option, which
13 * Alexey Kuznetsov allow both IPv4 and IPv6 sockets to bind
14 * a single port at the same time.
15 * Kazunori MIYAZAWA @USAGI: change process style to use ip6_append_data
16 * YOSHIFUJI Hideaki @USAGI: convert /proc/net/udp6 to seq_file.
17 *
18 * This program is free software; you can redistribute it and/or
19 * modify it under the terms of the GNU General Public License
20 * as published by the Free Software Foundation; either version
21 * 2 of the License, or (at your option) any later version.
22 */
23
24#include <linux/errno.h>
25#include <linux/types.h>
26#include <linux/socket.h>
27#include <linux/sockios.h>
28#include <linux/net.h>
29#include <linux/in6.h>
30#include <linux/netdevice.h>
31#include <linux/if_arp.h>
32#include <linux/ipv6.h>
33#include <linux/icmpv6.h>
34#include <linux/init.h>
35#include <linux/module.h>
36#include <linux/skbuff.h>
37#include <linux/slab.h>
38#include <linux/uaccess.h>
39
40#include <net/addrconf.h>
41#include <net/ndisc.h>
42#include <net/protocol.h>
43#include <net/transp_v6.h>
44#include <net/ip6_route.h>
45#include <net/raw.h>
46#include <net/tcp_states.h>
47#include <net/ip6_checksum.h>
48#include <net/xfrm.h>
49#include <net/inet_hashtables.h>
50#include <net/inet6_hashtables.h>
51#include <net/busy_poll.h>
52#include <net/sock_reuseport.h>
53
54#include <linux/proc_fs.h>
55#include <linux/seq_file.h>
56#include <trace/events/skb.h>
57#include "udp_impl.h"
58
59static bool udp6_lib_exact_dif_match(struct net *net, struct sk_buff *skb)
60{
61#if defined(CONFIG_NET_L3_MASTER_DEV)
62 if (!net->ipv4.sysctl_udp_l3mdev_accept &&
63 skb && ipv6_l3mdev_skb(IP6CB(skb)->flags))
64 return true;
65#endif
66 return false;
67}
68
69static u32 udp6_ehashfn(const struct net *net,
70 const struct in6_addr *laddr,
71 const u16 lport,
72 const struct in6_addr *faddr,
73 const __be16 fport)
74{
75 static u32 udp6_ehash_secret __read_mostly;
76 static u32 udp_ipv6_hash_secret __read_mostly;
77
78 u32 lhash, fhash;
79
80 net_get_random_once(&udp6_ehash_secret,
81 sizeof(udp6_ehash_secret));
82 net_get_random_once(&udp_ipv6_hash_secret,
83 sizeof(udp_ipv6_hash_secret));
84
85 lhash = (__force u32)laddr->s6_addr32[3];
86 fhash = __ipv6_addr_jhash(faddr, udp_ipv6_hash_secret);
87
88 return __inet6_ehashfn(lhash, lport, fhash, fport,
89 udp_ipv6_hash_secret + net_hash_mix(net));
90}
91
92int udp_v6_get_port(struct sock *sk, unsigned short snum)
93{
94 unsigned int hash2_nulladdr =
95 ipv6_portaddr_hash(sock_net(sk), &in6addr_any, snum);
96 unsigned int hash2_partial =
97 ipv6_portaddr_hash(sock_net(sk), &sk->sk_v6_rcv_saddr, 0);
98
99 /* precompute partial secondary hash */
100 udp_sk(sk)->udp_portaddr_hash = hash2_partial;
101 return udp_lib_get_port(sk, snum, hash2_nulladdr);
102}
103
104static void udp_v6_rehash(struct sock *sk)
105{
106 u16 new_hash = ipv6_portaddr_hash(sock_net(sk),
107 &sk->sk_v6_rcv_saddr,
108 inet_sk(sk)->inet_num);
109
110 udp_lib_rehash(sk, new_hash);
111}
112
113static int compute_score(struct sock *sk, struct net *net,
114 const struct in6_addr *saddr, __be16 sport,
115 const struct in6_addr *daddr, unsigned short hnum,
116 int dif, int sdif, bool exact_dif)
117{
118 int score;
119 struct inet_sock *inet;
120
121 if (!net_eq(sock_net(sk), net) ||
122 udp_sk(sk)->udp_port_hash != hnum ||
123 sk->sk_family != PF_INET6)
124 return -1;
125
126 score = 0;
127 inet = inet_sk(sk);
128
129 if (inet->inet_dport) {
130 if (inet->inet_dport != sport)
131 return -1;
132 score++;
133 }
134
135 if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr)) {
136 if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
137 return -1;
138 score++;
139 }
140
141 if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
142 if (!ipv6_addr_equal(&sk->sk_v6_daddr, saddr))
143 return -1;
144 score++;
145 }
146
147 if (sk->sk_bound_dev_if || exact_dif) {
148 bool dev_match = (sk->sk_bound_dev_if == dif ||
149 sk->sk_bound_dev_if == sdif);
150
151 if (!dev_match)
152 return -1;
153 if (sk->sk_bound_dev_if)
154 score++;
155 }
156
157 if (sk->sk_incoming_cpu == raw_smp_processor_id())
158 score++;
159
160 return score;
161}
162
163/* called with rcu_read_lock() */
164static struct sock *udp6_lib_lookup2(struct net *net,
165 const struct in6_addr *saddr, __be16 sport,
166 const struct in6_addr *daddr, unsigned int hnum,
167 int dif, int sdif, bool exact_dif,
168 struct udp_hslot *hslot2, struct sk_buff *skb)
169{
170 struct sock *sk, *result;
171 int score, badness;
172 u32 hash = 0;
173
174 result = NULL;
175 badness = -1;
176 udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) {
177 score = compute_score(sk, net, saddr, sport,
178 daddr, hnum, dif, sdif, exact_dif);
179 if (score > badness) {
180 if (sk->sk_reuseport) {
181 hash = udp6_ehashfn(net, daddr, hnum,
182 saddr, sport);
183
184 result = reuseport_select_sock(sk, hash, skb,
185 sizeof(struct udphdr));
186 if (result)
187 return result;
188 }
189 result = sk;
190 badness = score;
191 }
192 }
193 return result;
194}
195
196/* rcu_read_lock() must be held */
197struct sock *__udp6_lib_lookup(struct net *net,
198 const struct in6_addr *saddr, __be16 sport,
199 const struct in6_addr *daddr, __be16 dport,
200 int dif, int sdif, struct udp_table *udptable,
201 struct sk_buff *skb)
202{
203 struct sock *sk, *result;
204 unsigned short hnum = ntohs(dport);
205 unsigned int hash2, slot2, slot = udp_hashfn(net, hnum, udptable->mask);
206 struct udp_hslot *hslot2, *hslot = &udptable->hash[slot];
207 bool exact_dif = udp6_lib_exact_dif_match(net, skb);
208 int score, badness;
209 u32 hash = 0;
210
211 if (hslot->count > 10) {
212 hash2 = ipv6_portaddr_hash(net, daddr, hnum);
213 slot2 = hash2 & udptable->mask;
214 hslot2 = &udptable->hash2[slot2];
215 if (hslot->count < hslot2->count)
216 goto begin;
217
218 result = udp6_lib_lookup2(net, saddr, sport,
219 daddr, hnum, dif, sdif, exact_dif,
220 hslot2, skb);
221 if (!result) {
222 unsigned int old_slot2 = slot2;
223 hash2 = ipv6_portaddr_hash(net, &in6addr_any, hnum);
224 slot2 = hash2 & udptable->mask;
225 /* avoid searching the same slot again. */
226 if (unlikely(slot2 == old_slot2))
227 return result;
228
229 hslot2 = &udptable->hash2[slot2];
230 if (hslot->count < hslot2->count)
231 goto begin;
232
233 result = udp6_lib_lookup2(net, saddr, sport,
234 daddr, hnum, dif, sdif,
235 exact_dif, hslot2,
236 skb);
237 }
238 return result;
239 }
240begin:
241 result = NULL;
242 badness = -1;
243 sk_for_each_rcu(sk, &hslot->head) {
244 score = compute_score(sk, net, saddr, sport, daddr, hnum, dif,
245 sdif, exact_dif);
246 if (score > badness) {
247 if (sk->sk_reuseport) {
248 hash = udp6_ehashfn(net, daddr, hnum,
249 saddr, sport);
250 result = reuseport_select_sock(sk, hash, skb,
251 sizeof(struct udphdr));
252 if (result)
253 return result;
254 }
255 result = sk;
256 badness = score;
257 }
258 }
259 return result;
260}
261EXPORT_SYMBOL_GPL(__udp6_lib_lookup);
262
263static struct sock *__udp6_lib_lookup_skb(struct sk_buff *skb,
264 __be16 sport, __be16 dport,
265 struct udp_table *udptable)
266{
267 const struct ipv6hdr *iph = ipv6_hdr(skb);
268
269 return __udp6_lib_lookup(dev_net(skb->dev), &iph->saddr, sport,
270 &iph->daddr, dport, inet6_iif(skb),
271 inet6_sdif(skb), udptable, skb);
272}
273
274struct sock *udp6_lib_lookup_skb(struct sk_buff *skb,
275 __be16 sport, __be16 dport)
276{
277 const struct ipv6hdr *iph = ipv6_hdr(skb);
278
279 return __udp6_lib_lookup(dev_net(skb->dev), &iph->saddr, sport,
280 &iph->daddr, dport, inet6_iif(skb),
281 inet6_sdif(skb), &udp_table, skb);
282}
283EXPORT_SYMBOL_GPL(udp6_lib_lookup_skb);
284
285/* Must be called under rcu_read_lock().
286 * Does increment socket refcount.
287 */
288#if IS_ENABLED(CONFIG_NETFILTER_XT_MATCH_SOCKET) || \
289 IS_ENABLED(CONFIG_NETFILTER_XT_TARGET_TPROXY) || \
290 IS_ENABLED(CONFIG_NF_SOCKET_IPV6)
291struct sock *udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport,
292 const struct in6_addr *daddr, __be16 dport, int dif)
293{
294 struct sock *sk;
295
296 sk = __udp6_lib_lookup(net, saddr, sport, daddr, dport,
297 dif, 0, &udp_table, NULL);
298 if (sk && !refcount_inc_not_zero(&sk->sk_refcnt))
299 sk = NULL;
300 return sk;
301}
302EXPORT_SYMBOL_GPL(udp6_lib_lookup);
303#endif
304
305/* do not use the scratch area len for jumbogram: their length execeeds the
306 * scratch area space; note that the IP6CB flags is still in the first
307 * cacheline, so checking for jumbograms is cheap
308 */
309static int udp6_skb_len(struct sk_buff *skb)
310{
311 return unlikely(inet6_is_jumbogram(skb)) ? skb->len : udp_skb_len(skb);
312}
313
314/*
315 * This should be easy, if there is something there we
316 * return it, otherwise we block.
317 */
318
319int udpv6_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
320 int noblock, int flags, int *addr_len)
321{
322 struct ipv6_pinfo *np = inet6_sk(sk);
323 struct inet_sock *inet = inet_sk(sk);
324 struct sk_buff *skb;
325 unsigned int ulen, copied;
326 int peeked, peeking, off;
327 int err;
328 int is_udplite = IS_UDPLITE(sk);
329 bool checksum_valid = false;
330 int is_udp4;
331
332 if (flags & MSG_ERRQUEUE)
333 return ipv6_recv_error(sk, msg, len, addr_len);
334
335 if (np->rxpmtu && np->rxopt.bits.rxpmtu)
336 return ipv6_recv_rxpmtu(sk, msg, len, addr_len);
337
338try_again:
339 peeking = flags & MSG_PEEK;
340 off = sk_peek_offset(sk, flags);
341 skb = __skb_recv_udp(sk, flags, noblock, &peeked, &off, &err);
342 if (!skb)
343 return err;
344
345 ulen = udp6_skb_len(skb);
346 copied = len;
347 if (copied > ulen - off)
348 copied = ulen - off;
349 else if (copied < ulen)
350 msg->msg_flags |= MSG_TRUNC;
351
352 is_udp4 = (skb->protocol == htons(ETH_P_IP));
353
354 /*
355 * If checksum is needed at all, try to do it while copying the
356 * data. If the data is truncated, or if we only want a partial
357 * coverage checksum (UDP-Lite), do it before the copy.
358 */
359
360 if (copied < ulen || peeking ||
361 (is_udplite && UDP_SKB_CB(skb)->partial_cov)) {
362 checksum_valid = udp_skb_csum_unnecessary(skb) ||
363 !__udp_lib_checksum_complete(skb);
364 if (!checksum_valid)
365 goto csum_copy_err;
366 }
367
368 if (checksum_valid || udp_skb_csum_unnecessary(skb)) {
369 if (udp_skb_is_linear(skb))
370 err = copy_linear_skb(skb, copied, off, &msg->msg_iter);
371 else
372 err = skb_copy_datagram_msg(skb, off, msg, copied);
373 } else {
374 err = skb_copy_and_csum_datagram_msg(skb, off, msg);
375 if (err == -EINVAL)
376 goto csum_copy_err;
377 }
378 if (unlikely(err)) {
379 if (!peeked) {
380 atomic_inc(&sk->sk_drops);
381 if (is_udp4)
382 UDP_INC_STATS(sock_net(sk), UDP_MIB_INERRORS,
383 is_udplite);
384 else
385 UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS,
386 is_udplite);
387 }
388 kfree_skb(skb);
389 return err;
390 }
391 if (!peeked) {
392 if (is_udp4)
393 UDP_INC_STATS(sock_net(sk), UDP_MIB_INDATAGRAMS,
394 is_udplite);
395 else
396 UDP6_INC_STATS(sock_net(sk), UDP_MIB_INDATAGRAMS,
397 is_udplite);
398 }
399
400 sock_recv_ts_and_drops(msg, sk, skb);
401
402 /* Copy the address. */
403 if (msg->msg_name) {
404 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
405 sin6->sin6_family = AF_INET6;
406 sin6->sin6_port = udp_hdr(skb)->source;
407 sin6->sin6_flowinfo = 0;
408
409 if (is_udp4) {
410 ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
411 &sin6->sin6_addr);
412 sin6->sin6_scope_id = 0;
413 } else {
414 sin6->sin6_addr = ipv6_hdr(skb)->saddr;
415 sin6->sin6_scope_id =
416 ipv6_iface_scope_id(&sin6->sin6_addr,
417 inet6_iif(skb));
418 }
419 *addr_len = sizeof(*sin6);
420 }
421
422 if (np->rxopt.all)
423 ip6_datagram_recv_common_ctl(sk, msg, skb);
424
425 if (is_udp4) {
426 if (inet->cmsg_flags)
427 ip_cmsg_recv_offset(msg, sk, skb,
428 sizeof(struct udphdr), off);
429 } else {
430 if (np->rxopt.all)
431 ip6_datagram_recv_specific_ctl(sk, msg, skb);
432 }
433
434 err = copied;
435 if (flags & MSG_TRUNC)
436 err = ulen;
437
438 skb_consume_udp(sk, skb, peeking ? -err : err);
439 return err;
440
441csum_copy_err:
442 if (!__sk_queue_drop_skb(sk, &udp_sk(sk)->reader_queue, skb, flags,
443 udp_skb_destructor)) {
444 if (is_udp4) {
445 UDP_INC_STATS(sock_net(sk),
446 UDP_MIB_CSUMERRORS, is_udplite);
447 UDP_INC_STATS(sock_net(sk),
448 UDP_MIB_INERRORS, is_udplite);
449 } else {
450 UDP6_INC_STATS(sock_net(sk),
451 UDP_MIB_CSUMERRORS, is_udplite);
452 UDP6_INC_STATS(sock_net(sk),
453 UDP_MIB_INERRORS, is_udplite);
454 }
455 }
456 kfree_skb(skb);
457
458 /* starting over for a new packet, but check if we need to yield */
459 cond_resched();
460 msg->msg_flags &= ~MSG_TRUNC;
461 goto try_again;
462}
463
464void __udp6_lib_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
465 u8 type, u8 code, int offset, __be32 info,
466 struct udp_table *udptable)
467{
468 struct ipv6_pinfo *np;
469 const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data;
470 const struct in6_addr *saddr = &hdr->saddr;
471 const struct in6_addr *daddr = &hdr->daddr;
472 struct udphdr *uh = (struct udphdr *)(skb->data+offset);
473 struct sock *sk;
474 int harderr;
475 int err;
476 struct net *net = dev_net(skb->dev);
477
478 sk = __udp6_lib_lookup(net, daddr, uh->dest, saddr, uh->source,
479 inet6_iif(skb), 0, udptable, skb);
480 if (!sk) {
481 __ICMP6_INC_STATS(net, __in6_dev_get(skb->dev),
482 ICMP6_MIB_INERRORS);
483 return;
484 }
485
486 harderr = icmpv6_err_convert(type, code, &err);
487 np = inet6_sk(sk);
488
489 if (type == ICMPV6_PKT_TOOBIG) {
490 if (!ip6_sk_accept_pmtu(sk))
491 goto out;
492 ip6_sk_update_pmtu(skb, sk, info);
493 if (np->pmtudisc != IPV6_PMTUDISC_DONT)
494 harderr = 1;
495 }
496 if (type == NDISC_REDIRECT) {
497 ip6_sk_redirect(skb, sk);
498 goto out;
499 }
500
501 if (!np->recverr) {
502 if (!harderr || sk->sk_state != TCP_ESTABLISHED)
503 goto out;
504 } else {
505 ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1));
506 }
507
508 sk->sk_err = err;
509 sk->sk_error_report(sk);
510out:
511 return;
512}
513
514static int __udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
515{
516 int rc;
517
518 if (!ipv6_addr_any(&sk->sk_v6_daddr)) {
519 sock_rps_save_rxhash(sk, skb);
520 sk_mark_napi_id(sk, skb);
521 sk_incoming_cpu_update(sk);
522 } else {
523 sk_mark_napi_id_once(sk, skb);
524 }
525
526 rc = __udp_enqueue_schedule_skb(sk, skb);
527 if (rc < 0) {
528 int is_udplite = IS_UDPLITE(sk);
529
530 /* Note that an ENOMEM error is charged twice */
531 if (rc == -ENOMEM)
532 UDP6_INC_STATS(sock_net(sk),
533 UDP_MIB_RCVBUFERRORS, is_udplite);
534 UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
535 kfree_skb(skb);
536 return -1;
537 }
538
539 return 0;
540}
541
542static __inline__ void udpv6_err(struct sk_buff *skb,
543 struct inet6_skb_parm *opt, u8 type,
544 u8 code, int offset, __be32 info)
545{
546 __udp6_lib_err(skb, opt, type, code, offset, info, &udp_table);
547}
548
549static struct static_key udpv6_encap_needed __read_mostly;
550void udpv6_encap_enable(void)
551{
552 static_key_enable(&udpv6_encap_needed);
553}
554EXPORT_SYMBOL(udpv6_encap_enable);
555
556static int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
557{
558 struct udp_sock *up = udp_sk(sk);
559 int is_udplite = IS_UDPLITE(sk);
560
561 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
562 goto drop;
563
564 if (static_key_false(&udpv6_encap_needed) && up->encap_type) {
565 int (*encap_rcv)(struct sock *sk, struct sk_buff *skb);
566
567 /*
568 * This is an encapsulation socket so pass the skb to
569 * the socket's udp_encap_rcv() hook. Otherwise, just
570 * fall through and pass this up the UDP socket.
571 * up->encap_rcv() returns the following value:
572 * =0 if skb was successfully passed to the encap
573 * handler or was discarded by it.
574 * >0 if skb should be passed on to UDP.
575 * <0 if skb should be resubmitted as proto -N
576 */
577
578 /* if we're overly short, let UDP handle it */
579 encap_rcv = READ_ONCE(up->encap_rcv);
580 if (encap_rcv) {
581 int ret;
582
583 /* Verify checksum before giving to encap */
584 if (udp_lib_checksum_complete(skb))
585 goto csum_error;
586
587 ret = encap_rcv(sk, skb);
588 if (ret <= 0) {
589 __UDP_INC_STATS(sock_net(sk),
590 UDP_MIB_INDATAGRAMS,
591 is_udplite);
592 return -ret;
593 }
594 }
595
596 /* FALLTHROUGH -- it's a UDP Packet */
597 }
598
599 /*
600 * UDP-Lite specific tests, ignored on UDP sockets (see net/ipv4/udp.c).
601 */
602 if ((is_udplite & UDPLITE_RECV_CC) && UDP_SKB_CB(skb)->partial_cov) {
603
604 if (up->pcrlen == 0) { /* full coverage was set */
605 net_dbg_ratelimited("UDPLITE6: partial coverage %d while full coverage %d requested\n",
606 UDP_SKB_CB(skb)->cscov, skb->len);
607 goto drop;
608 }
609 if (UDP_SKB_CB(skb)->cscov < up->pcrlen) {
610 net_dbg_ratelimited("UDPLITE6: coverage %d too small, need min %d\n",
611 UDP_SKB_CB(skb)->cscov, up->pcrlen);
612 goto drop;
613 }
614 }
615
616 prefetch(&sk->sk_rmem_alloc);
617 if (rcu_access_pointer(sk->sk_filter) &&
618 udp_lib_checksum_complete(skb))
619 goto csum_error;
620
621 if (sk_filter_trim_cap(sk, skb, sizeof(struct udphdr)))
622 goto drop;
623
624 udp_csum_pull_header(skb);
625
626 skb_dst_drop(skb);
627
628 return __udpv6_queue_rcv_skb(sk, skb);
629
630csum_error:
631 __UDP6_INC_STATS(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite);
632drop:
633 __UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
634 atomic_inc(&sk->sk_drops);
635 kfree_skb(skb);
636 return -1;
637}
638
639static bool __udp_v6_is_mcast_sock(struct net *net, struct sock *sk,
640 __be16 loc_port, const struct in6_addr *loc_addr,
641 __be16 rmt_port, const struct in6_addr *rmt_addr,
642 int dif, unsigned short hnum)
643{
644 struct inet_sock *inet = inet_sk(sk);
645
646 if (!net_eq(sock_net(sk), net))
647 return false;
648
649 if (udp_sk(sk)->udp_port_hash != hnum ||
650 sk->sk_family != PF_INET6 ||
651 (inet->inet_dport && inet->inet_dport != rmt_port) ||
652 (!ipv6_addr_any(&sk->sk_v6_daddr) &&
653 !ipv6_addr_equal(&sk->sk_v6_daddr, rmt_addr)) ||
654 (sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif) ||
655 (!ipv6_addr_any(&sk->sk_v6_rcv_saddr) &&
656 !ipv6_addr_equal(&sk->sk_v6_rcv_saddr, loc_addr)))
657 return false;
658 if (!inet6_mc_check(sk, loc_addr, rmt_addr))
659 return false;
660 return true;
661}
662
663static void udp6_csum_zero_error(struct sk_buff *skb)
664{
665 /* RFC 2460 section 8.1 says that we SHOULD log
666 * this error. Well, it is reasonable.
667 */
668 net_dbg_ratelimited("IPv6: udp checksum is 0 for [%pI6c]:%u->[%pI6c]:%u\n",
669 &ipv6_hdr(skb)->saddr, ntohs(udp_hdr(skb)->source),
670 &ipv6_hdr(skb)->daddr, ntohs(udp_hdr(skb)->dest));
671}
672
673/*
674 * Note: called only from the BH handler context,
675 * so we don't need to lock the hashes.
676 */
677static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
678 const struct in6_addr *saddr, const struct in6_addr *daddr,
679 struct udp_table *udptable, int proto)
680{
681 struct sock *sk, *first = NULL;
682 const struct udphdr *uh = udp_hdr(skb);
683 unsigned short hnum = ntohs(uh->dest);
684 struct udp_hslot *hslot = udp_hashslot(udptable, net, hnum);
685 unsigned int offset = offsetof(typeof(*sk), sk_node);
686 unsigned int hash2 = 0, hash2_any = 0, use_hash2 = (hslot->count > 10);
687 int dif = inet6_iif(skb);
688 struct hlist_node *node;
689 struct sk_buff *nskb;
690
691 if (use_hash2) {
692 hash2_any = ipv6_portaddr_hash(net, &in6addr_any, hnum) &
693 udptable->mask;
694 hash2 = ipv6_portaddr_hash(net, daddr, hnum) & udptable->mask;
695start_lookup:
696 hslot = &udptable->hash2[hash2];
697 offset = offsetof(typeof(*sk), __sk_common.skc_portaddr_node);
698 }
699
700 sk_for_each_entry_offset_rcu(sk, node, &hslot->head, offset) {
701 if (!__udp_v6_is_mcast_sock(net, sk, uh->dest, daddr,
702 uh->source, saddr, dif, hnum))
703 continue;
704 /* If zero checksum and no_check is not on for
705 * the socket then skip it.
706 */
707 if (!uh->check && !udp_sk(sk)->no_check6_rx)
708 continue;
709 if (!first) {
710 first = sk;
711 continue;
712 }
713 nskb = skb_clone(skb, GFP_ATOMIC);
714 if (unlikely(!nskb)) {
715 atomic_inc(&sk->sk_drops);
716 __UDP6_INC_STATS(net, UDP_MIB_RCVBUFERRORS,
717 IS_UDPLITE(sk));
718 __UDP6_INC_STATS(net, UDP_MIB_INERRORS,
719 IS_UDPLITE(sk));
720 continue;
721 }
722
723 if (udpv6_queue_rcv_skb(sk, nskb) > 0)
724 consume_skb(nskb);
725 }
726
727 /* Also lookup *:port if we are using hash2 and haven't done so yet. */
728 if (use_hash2 && hash2 != hash2_any) {
729 hash2 = hash2_any;
730 goto start_lookup;
731 }
732
733 if (first) {
734 if (udpv6_queue_rcv_skb(first, skb) > 0)
735 consume_skb(skb);
736 } else {
737 kfree_skb(skb);
738 __UDP6_INC_STATS(net, UDP_MIB_IGNOREDMULTI,
739 proto == IPPROTO_UDPLITE);
740 }
741 return 0;
742}
743
744static void udp6_sk_rx_dst_set(struct sock *sk, struct dst_entry *dst)
745{
746 if (udp_sk_rx_dst_set(sk, dst)) {
747 const struct rt6_info *rt = (const struct rt6_info *)dst;
748
749 inet6_sk(sk)->rx_dst_cookie = rt6_get_cookie(rt);
750 }
751}
752
753int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
754 int proto)
755{
756 const struct in6_addr *saddr, *daddr;
757 struct net *net = dev_net(skb->dev);
758 struct udphdr *uh;
759 struct sock *sk;
760 u32 ulen = 0;
761
762 if (!pskb_may_pull(skb, sizeof(struct udphdr)))
763 goto discard;
764
765 saddr = &ipv6_hdr(skb)->saddr;
766 daddr = &ipv6_hdr(skb)->daddr;
767 uh = udp_hdr(skb);
768
769 ulen = ntohs(uh->len);
770 if (ulen > skb->len)
771 goto short_packet;
772
773 if (proto == IPPROTO_UDP) {
774 /* UDP validates ulen. */
775
776 /* Check for jumbo payload */
777 if (ulen == 0)
778 ulen = skb->len;
779
780 if (ulen < sizeof(*uh))
781 goto short_packet;
782
783 if (ulen < skb->len) {
784 if (pskb_trim_rcsum(skb, ulen))
785 goto short_packet;
786 saddr = &ipv6_hdr(skb)->saddr;
787 daddr = &ipv6_hdr(skb)->daddr;
788 uh = udp_hdr(skb);
789 }
790 }
791
792 if (udp6_csum_init(skb, uh, proto))
793 goto csum_error;
794
795 /* Check if the socket is already available, e.g. due to early demux */
796 sk = skb_steal_sock(skb);
797 if (sk) {
798 struct dst_entry *dst = skb_dst(skb);
799 int ret;
800
801 if (unlikely(sk->sk_rx_dst != dst))
802 udp6_sk_rx_dst_set(sk, dst);
803
804 ret = udpv6_queue_rcv_skb(sk, skb);
805 sock_put(sk);
806
807 /* a return value > 0 means to resubmit the input */
808 if (ret > 0)
809 return ret;
810 return 0;
811 }
812
813 /*
814 * Multicast receive code
815 */
816 if (ipv6_addr_is_multicast(daddr))
817 return __udp6_lib_mcast_deliver(net, skb,
818 saddr, daddr, udptable, proto);
819
820 /* Unicast */
821 sk = __udp6_lib_lookup_skb(skb, uh->source, uh->dest, udptable);
822 if (sk) {
823 int ret;
824
825 if (!uh->check && !udp_sk(sk)->no_check6_rx) {
826 udp6_csum_zero_error(skb);
827 goto csum_error;
828 }
829
830 if (inet_get_convert_csum(sk) && uh->check && !IS_UDPLITE(sk))
831 skb_checksum_try_convert(skb, IPPROTO_UDP, uh->check,
832 ip6_compute_pseudo);
833
834 ret = udpv6_queue_rcv_skb(sk, skb);
835
836 /* a return value > 0 means to resubmit the input */
837 if (ret > 0)
838 return ret;
839
840 return 0;
841 }
842
843 if (!uh->check) {
844 udp6_csum_zero_error(skb);
845 goto csum_error;
846 }
847
848 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
849 goto discard;
850
851 if (udp_lib_checksum_complete(skb))
852 goto csum_error;
853
854 __UDP6_INC_STATS(net, UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE);
855 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
856
857 kfree_skb(skb);
858 return 0;
859
860short_packet:
861 net_dbg_ratelimited("UDP%sv6: short packet: From [%pI6c]:%u %d/%d to [%pI6c]:%u\n",
862 proto == IPPROTO_UDPLITE ? "-Lite" : "",
863 saddr, ntohs(uh->source),
864 ulen, skb->len,
865 daddr, ntohs(uh->dest));
866 goto discard;
867csum_error:
868 __UDP6_INC_STATS(net, UDP_MIB_CSUMERRORS, proto == IPPROTO_UDPLITE);
869discard:
870 __UDP6_INC_STATS(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE);
871 kfree_skb(skb);
872 return 0;
873}
874
875
876static struct sock *__udp6_lib_demux_lookup(struct net *net,
877 __be16 loc_port, const struct in6_addr *loc_addr,
878 __be16 rmt_port, const struct in6_addr *rmt_addr,
879 int dif, int sdif)
880{
881 unsigned short hnum = ntohs(loc_port);
882 unsigned int hash2 = ipv6_portaddr_hash(net, loc_addr, hnum);
883 unsigned int slot2 = hash2 & udp_table.mask;
884 struct udp_hslot *hslot2 = &udp_table.hash2[slot2];
885 const __portpair ports = INET_COMBINED_PORTS(rmt_port, hnum);
886 struct sock *sk;
887
888 udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) {
889 if (sk->sk_state == TCP_ESTABLISHED &&
890 INET6_MATCH(sk, net, rmt_addr, loc_addr, ports, dif, sdif))
891 return sk;
892 /* Only check first socket in chain */
893 break;
894 }
895 return NULL;
896}
897
898static void udp_v6_early_demux(struct sk_buff *skb)
899{
900 struct net *net = dev_net(skb->dev);
901 const struct udphdr *uh;
902 struct sock *sk;
903 struct dst_entry *dst;
904 int dif = skb->dev->ifindex;
905 int sdif = inet6_sdif(skb);
906
907 if (!pskb_may_pull(skb, skb_transport_offset(skb) +
908 sizeof(struct udphdr)))
909 return;
910
911 uh = udp_hdr(skb);
912
913 if (skb->pkt_type == PACKET_HOST)
914 sk = __udp6_lib_demux_lookup(net, uh->dest,
915 &ipv6_hdr(skb)->daddr,
916 uh->source, &ipv6_hdr(skb)->saddr,
917 dif, sdif);
918 else
919 return;
920
921 if (!sk || !refcount_inc_not_zero(&sk->sk_refcnt))
922 return;
923
924 skb->sk = sk;
925 skb->destructor = sock_efree;
926 dst = READ_ONCE(sk->sk_rx_dst);
927
928 if (dst)
929 dst = dst_check(dst, inet6_sk(sk)->rx_dst_cookie);
930 if (dst) {
931 /* set noref for now.
932 * any place which wants to hold dst has to call
933 * dst_hold_safe()
934 */
935 skb_dst_set_noref(skb, dst);
936 }
937}
938
939static __inline__ int udpv6_rcv(struct sk_buff *skb)
940{
941 return __udp6_lib_rcv(skb, &udp_table, IPPROTO_UDP);
942}
943
944/*
945 * Throw away all pending data and cancel the corking. Socket is locked.
946 */
947static void udp_v6_flush_pending_frames(struct sock *sk)
948{
949 struct udp_sock *up = udp_sk(sk);
950
951 if (up->pending == AF_INET)
952 udp_flush_pending_frames(sk);
953 else if (up->pending) {
954 up->len = 0;
955 up->pending = 0;
956 ip6_flush_pending_frames(sk);
957 }
958}
959
960static int udpv6_pre_connect(struct sock *sk, struct sockaddr *uaddr,
961 int addr_len)
962{
963 /* The following checks are replicated from __ip6_datagram_connect()
964 * and intended to prevent BPF program called below from accessing
965 * bytes that are out of the bound specified by user in addr_len.
966 */
967 if (uaddr->sa_family == AF_INET) {
968 if (__ipv6_only_sock(sk))
969 return -EAFNOSUPPORT;
970 return udp_pre_connect(sk, uaddr, addr_len);
971 }
972
973 if (addr_len < SIN6_LEN_RFC2133)
974 return -EINVAL;
975
976 return BPF_CGROUP_RUN_PROG_INET6_CONNECT_LOCK(sk, uaddr);
977}
978
979/**
980 * udp6_hwcsum_outgoing - handle outgoing HW checksumming
981 * @sk: socket we are sending on
982 * @skb: sk_buff containing the filled-in UDP header
983 * (checksum field must be zeroed out)
984 */
985static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb,
986 const struct in6_addr *saddr,
987 const struct in6_addr *daddr, int len)
988{
989 unsigned int offset;
990 struct udphdr *uh = udp_hdr(skb);
991 struct sk_buff *frags = skb_shinfo(skb)->frag_list;
992 __wsum csum = 0;
993
994 if (!frags) {
995 /* Only one fragment on the socket. */
996 skb->csum_start = skb_transport_header(skb) - skb->head;
997 skb->csum_offset = offsetof(struct udphdr, check);
998 uh->check = ~csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 0);
999 } else {
1000 /*
1001 * HW-checksum won't work as there are two or more
1002 * fragments on the socket so that all csums of sk_buffs
1003 * should be together
1004 */
1005 offset = skb_transport_offset(skb);
1006 skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
1007 csum = skb->csum;
1008
1009 skb->ip_summed = CHECKSUM_NONE;
1010
1011 do {
1012 csum = csum_add(csum, frags->csum);
1013 } while ((frags = frags->next));
1014
1015 uh->check = csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP,
1016 csum);
1017 if (uh->check == 0)
1018 uh->check = CSUM_MANGLED_0;
1019 }
1020}
1021
1022/*
1023 * Sending
1024 */
1025
1026static int udp_v6_send_skb(struct sk_buff *skb, struct flowi6 *fl6)
1027{
1028 struct sock *sk = skb->sk;
1029 struct udphdr *uh;
1030 int err = 0;
1031 int is_udplite = IS_UDPLITE(sk);
1032 __wsum csum = 0;
1033 int offset = skb_transport_offset(skb);
1034 int len = skb->len - offset;
1035
1036 /*
1037 * Create a UDP header
1038 */
1039 uh = udp_hdr(skb);
1040 uh->source = fl6->fl6_sport;
1041 uh->dest = fl6->fl6_dport;
1042 uh->len = htons(len);
1043 uh->check = 0;
1044
1045 if (is_udplite)
1046 csum = udplite_csum(skb);
1047 else if (udp_sk(sk)->no_check6_tx) { /* UDP csum disabled */
1048 skb->ip_summed = CHECKSUM_NONE;
1049 goto send;
1050 } else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */
1051 udp6_hwcsum_outgoing(sk, skb, &fl6->saddr, &fl6->daddr, len);
1052 goto send;
1053 } else
1054 csum = udp_csum(skb);
1055
1056 /* add protocol-dependent pseudo-header */
1057 uh->check = csum_ipv6_magic(&fl6->saddr, &fl6->daddr,
1058 len, fl6->flowi6_proto, csum);
1059 if (uh->check == 0)
1060 uh->check = CSUM_MANGLED_0;
1061
1062send:
1063 err = ip6_send_skb(skb);
1064 if (err) {
1065 if (err == -ENOBUFS && !inet6_sk(sk)->recverr) {
1066 UDP6_INC_STATS(sock_net(sk),
1067 UDP_MIB_SNDBUFERRORS, is_udplite);
1068 err = 0;
1069 }
1070 } else {
1071 UDP6_INC_STATS(sock_net(sk),
1072 UDP_MIB_OUTDATAGRAMS, is_udplite);
1073 }
1074 return err;
1075}
1076
1077static int udp_v6_push_pending_frames(struct sock *sk)
1078{
1079 struct sk_buff *skb;
1080 struct udp_sock *up = udp_sk(sk);
1081 struct flowi6 fl6;
1082 int err = 0;
1083
1084 if (up->pending == AF_INET)
1085 return udp_push_pending_frames(sk);
1086
1087 /* ip6_finish_skb will release the cork, so make a copy of
1088 * fl6 here.
1089 */
1090 fl6 = inet_sk(sk)->cork.fl.u.ip6;
1091
1092 skb = ip6_finish_skb(sk);
1093 if (!skb)
1094 goto out;
1095
1096 err = udp_v6_send_skb(skb, &fl6);
1097
1098out:
1099 up->len = 0;
1100 up->pending = 0;
1101 return err;
1102}
1103
1104int udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
1105{
1106 struct ipv6_txoptions opt_space;
1107 struct udp_sock *up = udp_sk(sk);
1108 struct inet_sock *inet = inet_sk(sk);
1109 struct ipv6_pinfo *np = inet6_sk(sk);
1110 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
1111 struct in6_addr *daddr, *final_p, final;
1112 struct ipv6_txoptions *opt = NULL;
1113 struct ipv6_txoptions *opt_to_free = NULL;
1114 struct ip6_flowlabel *flowlabel = NULL;
1115 struct flowi6 fl6;
1116 struct dst_entry *dst;
1117 struct ipcm6_cookie ipc6;
1118 int addr_len = msg->msg_namelen;
1119 bool connected = false;
1120 int ulen = len;
1121 int corkreq = up->corkflag || msg->msg_flags&MSG_MORE;
1122 int err;
1123 int is_udplite = IS_UDPLITE(sk);
1124 int (*getfrag)(void *, char *, int, int, int, struct sk_buff *);
1125 struct sockcm_cookie sockc;
1126
1127 ipc6.hlimit = -1;
1128 ipc6.tclass = -1;
1129 ipc6.dontfrag = -1;
1130 sockc.tsflags = sk->sk_tsflags;
1131
1132 /* destination address check */
1133 if (sin6) {
1134 if (addr_len < offsetof(struct sockaddr, sa_data))
1135 return -EINVAL;
1136
1137 switch (sin6->sin6_family) {
1138 case AF_INET6:
1139 if (addr_len < SIN6_LEN_RFC2133)
1140 return -EINVAL;
1141 daddr = &sin6->sin6_addr;
1142 if (ipv6_addr_any(daddr) &&
1143 ipv6_addr_v4mapped(&np->saddr))
1144 ipv6_addr_set_v4mapped(htonl(INADDR_LOOPBACK),
1145 daddr);
1146 break;
1147 case AF_INET:
1148 goto do_udp_sendmsg;
1149 case AF_UNSPEC:
1150 msg->msg_name = sin6 = NULL;
1151 msg->msg_namelen = addr_len = 0;
1152 daddr = NULL;
1153 break;
1154 default:
1155 return -EINVAL;
1156 }
1157 } else if (!up->pending) {
1158 if (sk->sk_state != TCP_ESTABLISHED)
1159 return -EDESTADDRREQ;
1160 daddr = &sk->sk_v6_daddr;
1161 } else
1162 daddr = NULL;
1163
1164 if (daddr) {
1165 if (ipv6_addr_v4mapped(daddr)) {
1166 struct sockaddr_in sin;
1167 sin.sin_family = AF_INET;
1168 sin.sin_port = sin6 ? sin6->sin6_port : inet->inet_dport;
1169 sin.sin_addr.s_addr = daddr->s6_addr32[3];
1170 msg->msg_name = &sin;
1171 msg->msg_namelen = sizeof(sin);
1172do_udp_sendmsg:
1173 if (__ipv6_only_sock(sk))
1174 return -ENETUNREACH;
1175 return udp_sendmsg(sk, msg, len);
1176 }
1177 }
1178
1179 if (up->pending == AF_INET)
1180 return udp_sendmsg(sk, msg, len);
1181
1182 /* Rough check on arithmetic overflow,
1183 better check is made in ip6_append_data().
1184 */
1185 if (len > INT_MAX - sizeof(struct udphdr))
1186 return -EMSGSIZE;
1187
1188 getfrag = is_udplite ? udplite_getfrag : ip_generic_getfrag;
1189 if (up->pending) {
1190 /*
1191 * There are pending frames.
1192 * The socket lock must be held while it's corked.
1193 */
1194 lock_sock(sk);
1195 if (likely(up->pending)) {
1196 if (unlikely(up->pending != AF_INET6)) {
1197 release_sock(sk);
1198 return -EAFNOSUPPORT;
1199 }
1200 dst = NULL;
1201 goto do_append_data;
1202 }
1203 release_sock(sk);
1204 }
1205 ulen += sizeof(struct udphdr);
1206
1207 memset(&fl6, 0, sizeof(fl6));
1208
1209 if (sin6) {
1210 if (sin6->sin6_port == 0)
1211 return -EINVAL;
1212
1213 fl6.fl6_dport = sin6->sin6_port;
1214 daddr = &sin6->sin6_addr;
1215
1216 if (np->sndflow) {
1217 fl6.flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK;
1218 if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) {
1219 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1220 if (!flowlabel)
1221 return -EINVAL;
1222 }
1223 }
1224
1225 /*
1226 * Otherwise it will be difficult to maintain
1227 * sk->sk_dst_cache.
1228 */
1229 if (sk->sk_state == TCP_ESTABLISHED &&
1230 ipv6_addr_equal(daddr, &sk->sk_v6_daddr))
1231 daddr = &sk->sk_v6_daddr;
1232
1233 if (addr_len >= sizeof(struct sockaddr_in6) &&
1234 sin6->sin6_scope_id &&
1235 __ipv6_addr_needs_scope_id(__ipv6_addr_type(daddr)))
1236 fl6.flowi6_oif = sin6->sin6_scope_id;
1237 } else {
1238 if (sk->sk_state != TCP_ESTABLISHED)
1239 return -EDESTADDRREQ;
1240
1241 fl6.fl6_dport = inet->inet_dport;
1242 daddr = &sk->sk_v6_daddr;
1243 fl6.flowlabel = np->flow_label;
1244 connected = true;
1245 }
1246
1247 if (!fl6.flowi6_oif)
1248 fl6.flowi6_oif = sk->sk_bound_dev_if;
1249
1250 if (!fl6.flowi6_oif)
1251 fl6.flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;
1252
1253 fl6.flowi6_mark = sk->sk_mark;
1254 fl6.flowi6_uid = sk->sk_uid;
1255
1256 if (msg->msg_controllen) {
1257 opt = &opt_space;
1258 memset(opt, 0, sizeof(struct ipv6_txoptions));
1259 opt->tot_len = sizeof(*opt);
1260 ipc6.opt = opt;
1261
1262 err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, &fl6, &ipc6, &sockc);
1263 if (err < 0) {
1264 fl6_sock_release(flowlabel);
1265 return err;
1266 }
1267 if ((fl6.flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) {
1268 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1269 if (!flowlabel)
1270 return -EINVAL;
1271 }
1272 if (!(opt->opt_nflen|opt->opt_flen))
1273 opt = NULL;
1274 connected = false;
1275 }
1276 if (!opt) {
1277 opt = txopt_get(np);
1278 opt_to_free = opt;
1279 }
1280 if (flowlabel)
1281 opt = fl6_merge_options(&opt_space, flowlabel, opt);
1282 opt = ipv6_fixup_options(&opt_space, opt);
1283 ipc6.opt = opt;
1284
1285 fl6.flowi6_proto = sk->sk_protocol;
1286 if (!ipv6_addr_any(daddr))
1287 fl6.daddr = *daddr;
1288 else
1289 fl6.daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */
1290 if (ipv6_addr_any(&fl6.saddr) && !ipv6_addr_any(&np->saddr))
1291 fl6.saddr = np->saddr;
1292 fl6.fl6_sport = inet->inet_sport;
1293
1294 final_p = fl6_update_dst(&fl6, opt, &final);
1295 if (final_p)
1296 connected = false;
1297
1298 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr)) {
1299 fl6.flowi6_oif = np->mcast_oif;
1300 connected = false;
1301 } else if (!fl6.flowi6_oif)
1302 fl6.flowi6_oif = np->ucast_oif;
1303
1304 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
1305
1306 if (ipc6.tclass < 0)
1307 ipc6.tclass = np->tclass;
1308
1309 fl6.flowlabel = ip6_make_flowinfo(ipc6.tclass, fl6.flowlabel);
1310
1311 dst = ip6_sk_dst_lookup_flow(sk, &fl6, final_p, connected);
1312 if (IS_ERR(dst)) {
1313 err = PTR_ERR(dst);
1314 dst = NULL;
1315 goto out;
1316 }
1317
1318 if (ipc6.hlimit < 0)
1319 ipc6.hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
1320
1321 if (msg->msg_flags&MSG_CONFIRM)
1322 goto do_confirm;
1323back_from_confirm:
1324
1325 /* Lockless fast path for the non-corking case */
1326 if (!corkreq) {
1327 struct sk_buff *skb;
1328
1329 skb = ip6_make_skb(sk, getfrag, msg, ulen,
1330 sizeof(struct udphdr), &ipc6,
1331 &fl6, (struct rt6_info *)dst,
1332 msg->msg_flags, &sockc);
1333 err = PTR_ERR(skb);
1334 if (!IS_ERR_OR_NULL(skb))
1335 err = udp_v6_send_skb(skb, &fl6);
1336 goto out;
1337 }
1338
1339 lock_sock(sk);
1340 if (unlikely(up->pending)) {
1341 /* The socket is already corked while preparing it. */
1342 /* ... which is an evident application bug. --ANK */
1343 release_sock(sk);
1344
1345 net_dbg_ratelimited("udp cork app bug 2\n");
1346 err = -EINVAL;
1347 goto out;
1348 }
1349
1350 up->pending = AF_INET6;
1351
1352do_append_data:
1353 if (ipc6.dontfrag < 0)
1354 ipc6.dontfrag = np->dontfrag;
1355 up->len += ulen;
1356 err = ip6_append_data(sk, getfrag, msg, ulen, sizeof(struct udphdr),
1357 &ipc6, &fl6, (struct rt6_info *)dst,
1358 corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags, &sockc);
1359 if (err)
1360 udp_v6_flush_pending_frames(sk);
1361 else if (!corkreq)
1362 err = udp_v6_push_pending_frames(sk);
1363 else if (unlikely(skb_queue_empty(&sk->sk_write_queue)))
1364 up->pending = 0;
1365
1366 if (err > 0)
1367 err = np->recverr ? net_xmit_errno(err) : 0;
1368 release_sock(sk);
1369
1370out:
1371 dst_release(dst);
1372 fl6_sock_release(flowlabel);
1373 txopt_put(opt_to_free);
1374 if (!err)
1375 return len;
1376 /*
1377 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space. Reporting
1378 * ENOBUFS might not be good (it's not tunable per se), but otherwise
1379 * we don't have a good statistic (IpOutDiscards but it can be too many
1380 * things). We could add another new stat but at least for now that
1381 * seems like overkill.
1382 */
1383 if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) {
1384 UDP6_INC_STATS(sock_net(sk),
1385 UDP_MIB_SNDBUFERRORS, is_udplite);
1386 }
1387 return err;
1388
1389do_confirm:
1390 if (msg->msg_flags & MSG_PROBE)
1391 dst_confirm_neigh(dst, &fl6.daddr);
1392 if (!(msg->msg_flags&MSG_PROBE) || len)
1393 goto back_from_confirm;
1394 err = 0;
1395 goto out;
1396}
1397
1398void udpv6_destroy_sock(struct sock *sk)
1399{
1400 struct udp_sock *up = udp_sk(sk);
1401 lock_sock(sk);
1402 udp_v6_flush_pending_frames(sk);
1403 release_sock(sk);
1404
1405 if (static_key_false(&udpv6_encap_needed) && up->encap_type) {
1406 void (*encap_destroy)(struct sock *sk);
1407 encap_destroy = READ_ONCE(up->encap_destroy);
1408 if (encap_destroy)
1409 encap_destroy(sk);
1410 }
1411
1412 inet6_destroy_sock(sk);
1413}
1414
1415/*
1416 * Socket option code for UDP
1417 */
1418int udpv6_setsockopt(struct sock *sk, int level, int optname,
1419 char __user *optval, unsigned int optlen)
1420{
1421 if (level == SOL_UDP || level == SOL_UDPLITE)
1422 return udp_lib_setsockopt(sk, level, optname, optval, optlen,
1423 udp_v6_push_pending_frames);
1424 return ipv6_setsockopt(sk, level, optname, optval, optlen);
1425}
1426
1427#ifdef CONFIG_COMPAT
1428int compat_udpv6_setsockopt(struct sock *sk, int level, int optname,
1429 char __user *optval, unsigned int optlen)
1430{
1431 if (level == SOL_UDP || level == SOL_UDPLITE)
1432 return udp_lib_setsockopt(sk, level, optname, optval, optlen,
1433 udp_v6_push_pending_frames);
1434 return compat_ipv6_setsockopt(sk, level, optname, optval, optlen);
1435}
1436#endif
1437
1438int udpv6_getsockopt(struct sock *sk, int level, int optname,
1439 char __user *optval, int __user *optlen)
1440{
1441 if (level == SOL_UDP || level == SOL_UDPLITE)
1442 return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1443 return ipv6_getsockopt(sk, level, optname, optval, optlen);
1444}
1445
1446#ifdef CONFIG_COMPAT
1447int compat_udpv6_getsockopt(struct sock *sk, int level, int optname,
1448 char __user *optval, int __user *optlen)
1449{
1450 if (level == SOL_UDP || level == SOL_UDPLITE)
1451 return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1452 return compat_ipv6_getsockopt(sk, level, optname, optval, optlen);
1453}
1454#endif
1455
1456/* thinking of making this const? Don't.
1457 * early_demux can change based on sysctl.
1458 */
1459static struct inet6_protocol udpv6_protocol = {
1460 .early_demux = udp_v6_early_demux,
1461 .early_demux_handler = udp_v6_early_demux,
1462 .handler = udpv6_rcv,
1463 .err_handler = udpv6_err,
1464 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1465};
1466
1467/* ------------------------------------------------------------------------ */
1468#ifdef CONFIG_PROC_FS
1469int udp6_seq_show(struct seq_file *seq, void *v)
1470{
1471 if (v == SEQ_START_TOKEN) {
1472 seq_puts(seq, IPV6_SEQ_DGRAM_HEADER);
1473 } else {
1474 int bucket = ((struct udp_iter_state *)seq->private)->bucket;
1475 struct inet_sock *inet = inet_sk(v);
1476 __u16 srcp = ntohs(inet->inet_sport);
1477 __u16 destp = ntohs(inet->inet_dport);
1478 ip6_dgram_sock_seq_show(seq, v, srcp, destp, bucket);
1479 }
1480 return 0;
1481}
1482
1483static const struct file_operations udp6_afinfo_seq_fops = {
1484 .open = udp_seq_open,
1485 .read = seq_read,
1486 .llseek = seq_lseek,
1487 .release = seq_release_net
1488};
1489
1490static struct udp_seq_afinfo udp6_seq_afinfo = {
1491 .name = "udp6",
1492 .family = AF_INET6,
1493 .udp_table = &udp_table,
1494 .seq_fops = &udp6_afinfo_seq_fops,
1495 .seq_ops = {
1496 .show = udp6_seq_show,
1497 },
1498};
1499
1500int __net_init udp6_proc_init(struct net *net)
1501{
1502 return udp_proc_register(net, &udp6_seq_afinfo);
1503}
1504
1505void udp6_proc_exit(struct net *net)
1506{
1507 udp_proc_unregister(net, &udp6_seq_afinfo);
1508}
1509#endif /* CONFIG_PROC_FS */
1510
1511/* ------------------------------------------------------------------------ */
1512
1513struct proto udpv6_prot = {
1514 .name = "UDPv6",
1515 .owner = THIS_MODULE,
1516 .close = udp_lib_close,
1517 .pre_connect = udpv6_pre_connect,
1518 .connect = ip6_datagram_connect,
1519 .disconnect = udp_disconnect,
1520 .ioctl = udp_ioctl,
1521 .init = udp_init_sock,
1522 .destroy = udpv6_destroy_sock,
1523 .setsockopt = udpv6_setsockopt,
1524 .getsockopt = udpv6_getsockopt,
1525 .sendmsg = udpv6_sendmsg,
1526 .recvmsg = udpv6_recvmsg,
1527 .release_cb = ip6_datagram_release_cb,
1528 .hash = udp_lib_hash,
1529 .unhash = udp_lib_unhash,
1530 .rehash = udp_v6_rehash,
1531 .get_port = udp_v6_get_port,
1532 .memory_allocated = &udp_memory_allocated,
1533 .sysctl_mem = sysctl_udp_mem,
1534 .sysctl_wmem_offset = offsetof(struct net, ipv4.sysctl_udp_wmem_min),
1535 .sysctl_rmem_offset = offsetof(struct net, ipv4.sysctl_udp_rmem_min),
1536 .obj_size = sizeof(struct udp6_sock),
1537 .h.udp_table = &udp_table,
1538#ifdef CONFIG_COMPAT
1539 .compat_setsockopt = compat_udpv6_setsockopt,
1540 .compat_getsockopt = compat_udpv6_getsockopt,
1541#endif
1542 .diag_destroy = udp_abort,
1543};
1544
1545static struct inet_protosw udpv6_protosw = {
1546 .type = SOCK_DGRAM,
1547 .protocol = IPPROTO_UDP,
1548 .prot = &udpv6_prot,
1549 .ops = &inet6_dgram_ops,
1550 .flags = INET_PROTOSW_PERMANENT,
1551};
1552
1553int __init udpv6_init(void)
1554{
1555 int ret;
1556
1557 ret = inet6_add_protocol(&udpv6_protocol, IPPROTO_UDP);
1558 if (ret)
1559 goto out;
1560
1561 ret = inet6_register_protosw(&udpv6_protosw);
1562 if (ret)
1563 goto out_udpv6_protocol;
1564out:
1565 return ret;
1566
1567out_udpv6_protocol:
1568 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1569 goto out;
1570}
1571
1572void udpv6_exit(void)
1573{
1574 inet6_unregister_protosw(&udpv6_protosw);
1575 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1576}
1/*
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}