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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
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}
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
241static struct 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}
308
309static struct sock *__udp6_lib_lookup_skb(struct sk_buff *skb,
310 __be16 sport, __be16 dport,
311 struct udp_table *udptable)
312{
313 struct sock *sk;
314 const struct ipv6hdr *iph = ipv6_hdr(skb);
315
316 if (unlikely(sk = skb_steal_sock(skb)))
317 return sk;
318 return __udp6_lib_lookup(dev_net(skb_dst(skb)->dev), &iph->saddr, sport,
319 &iph->daddr, dport, inet6_iif(skb),
320 udptable);
321}
322
323struct sock *udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport,
324 const struct in6_addr *daddr, __be16 dport, int dif)
325{
326 return __udp6_lib_lookup(net, saddr, sport, daddr, dport, dif, &udp_table);
327}
328EXPORT_SYMBOL_GPL(udp6_lib_lookup);
329
330
331/*
332 * This should be easy, if there is something there we
333 * return it, otherwise we block.
334 */
335
336int udpv6_recvmsg(struct kiocb *iocb, struct sock *sk,
337 struct msghdr *msg, size_t len,
338 int noblock, int flags, int *addr_len)
339{
340 struct ipv6_pinfo *np = inet6_sk(sk);
341 struct inet_sock *inet = inet_sk(sk);
342 struct sk_buff *skb;
343 unsigned int ulen;
344 int peeked;
345 int err;
346 int is_udplite = IS_UDPLITE(sk);
347 int is_udp4;
348 bool slow;
349
350 if (addr_len)
351 *addr_len=sizeof(struct sockaddr_in6);
352
353 if (flags & MSG_ERRQUEUE)
354 return ipv6_recv_error(sk, msg, len);
355
356 if (np->rxpmtu && np->rxopt.bits.rxpmtu)
357 return ipv6_recv_rxpmtu(sk, msg, len);
358
359try_again:
360 skb = __skb_recv_datagram(sk, flags | (noblock ? MSG_DONTWAIT : 0),
361 &peeked, &err);
362 if (!skb)
363 goto out;
364
365 ulen = skb->len - sizeof(struct udphdr);
366 if (len > ulen)
367 len = ulen;
368 else if (len < ulen)
369 msg->msg_flags |= MSG_TRUNC;
370
371 is_udp4 = (skb->protocol == htons(ETH_P_IP));
372
373 /*
374 * If checksum is needed at all, try to do it while copying the
375 * data. If the data is truncated, or if we only want a partial
376 * coverage checksum (UDP-Lite), do it before the copy.
377 */
378
379 if (len < ulen || UDP_SKB_CB(skb)->partial_cov) {
380 if (udp_lib_checksum_complete(skb))
381 goto csum_copy_err;
382 }
383
384 if (skb_csum_unnecessary(skb))
385 err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr),
386 msg->msg_iov,len);
387 else {
388 err = skb_copy_and_csum_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov);
389 if (err == -EINVAL)
390 goto csum_copy_err;
391 }
392 if (err)
393 goto out_free;
394
395 if (!peeked) {
396 if (is_udp4)
397 UDP_INC_STATS_USER(sock_net(sk),
398 UDP_MIB_INDATAGRAMS, is_udplite);
399 else
400 UDP6_INC_STATS_USER(sock_net(sk),
401 UDP_MIB_INDATAGRAMS, is_udplite);
402 }
403
404 sock_recv_ts_and_drops(msg, sk, skb);
405
406 /* Copy the address. */
407 if (msg->msg_name) {
408 struct sockaddr_in6 *sin6;
409
410 sin6 = (struct sockaddr_in6 *) msg->msg_name;
411 sin6->sin6_family = AF_INET6;
412 sin6->sin6_port = udp_hdr(skb)->source;
413 sin6->sin6_flowinfo = 0;
414 sin6->sin6_scope_id = 0;
415
416 if (is_udp4)
417 ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
418 &sin6->sin6_addr);
419 else {
420 ipv6_addr_copy(&sin6->sin6_addr,
421 &ipv6_hdr(skb)->saddr);
422 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
423 sin6->sin6_scope_id = IP6CB(skb)->iif;
424 }
425
426 }
427 if (is_udp4) {
428 if (inet->cmsg_flags)
429 ip_cmsg_recv(msg, skb);
430 } else {
431 if (np->rxopt.all)
432 datagram_recv_ctl(sk, msg, skb);
433 }
434
435 err = len;
436 if (flags & MSG_TRUNC)
437 err = ulen;
438
439out_free:
440 skb_free_datagram_locked(sk, skb);
441out:
442 return err;
443
444csum_copy_err:
445 slow = lock_sock_fast(sk);
446 if (!skb_kill_datagram(sk, skb, flags)) {
447 if (is_udp4)
448 UDP_INC_STATS_USER(sock_net(sk),
449 UDP_MIB_INERRORS, is_udplite);
450 else
451 UDP6_INC_STATS_USER(sock_net(sk),
452 UDP_MIB_INERRORS, is_udplite);
453 }
454 unlock_sock_fast(sk, slow);
455
456 if (noblock)
457 return -EAGAIN;
458
459 /* starting over for a new packet */
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 err;
475
476 sk = __udp6_lib_lookup(dev_net(skb->dev), daddr, uh->dest,
477 saddr, uh->source, inet6_iif(skb), udptable);
478 if (sk == NULL)
479 return;
480
481 np = inet6_sk(sk);
482
483 if (!icmpv6_err_convert(type, code, &err) && !np->recverr)
484 goto out;
485
486 if (sk->sk_state != TCP_ESTABLISHED && !np->recverr)
487 goto out;
488
489 if (np->recverr)
490 ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1));
491
492 sk->sk_err = err;
493 sk->sk_error_report(sk);
494out:
495 sock_put(sk);
496}
497
498static __inline__ void udpv6_err(struct sk_buff *skb,
499 struct inet6_skb_parm *opt, u8 type,
500 u8 code, int offset, __be32 info )
501{
502 __udp6_lib_err(skb, opt, type, code, offset, info, &udp_table);
503}
504
505int udpv6_queue_rcv_skb(struct sock * sk, struct sk_buff *skb)
506{
507 struct udp_sock *up = udp_sk(sk);
508 int rc;
509 int is_udplite = IS_UDPLITE(sk);
510
511 if (!ipv6_addr_any(&inet6_sk(sk)->daddr))
512 sock_rps_save_rxhash(sk, skb->rxhash);
513
514 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
515 goto drop;
516
517 /*
518 * UDP-Lite specific tests, ignored on UDP sockets (see net/ipv4/udp.c).
519 */
520 if ((is_udplite & UDPLITE_RECV_CC) && UDP_SKB_CB(skb)->partial_cov) {
521
522 if (up->pcrlen == 0) { /* full coverage was set */
523 LIMIT_NETDEBUG(KERN_WARNING "UDPLITE6: partial coverage"
524 " %d while full coverage %d requested\n",
525 UDP_SKB_CB(skb)->cscov, skb->len);
526 goto drop;
527 }
528 if (UDP_SKB_CB(skb)->cscov < up->pcrlen) {
529 LIMIT_NETDEBUG(KERN_WARNING "UDPLITE6: coverage %d "
530 "too small, need min %d\n",
531 UDP_SKB_CB(skb)->cscov, up->pcrlen);
532 goto drop;
533 }
534 }
535
536 if (rcu_dereference_raw(sk->sk_filter)) {
537 if (udp_lib_checksum_complete(skb))
538 goto drop;
539 }
540
541 if ((rc = ip_queue_rcv_skb(sk, skb)) < 0) {
542 /* Note that an ENOMEM error is charged twice */
543 if (rc == -ENOMEM)
544 UDP6_INC_STATS_BH(sock_net(sk),
545 UDP_MIB_RCVBUFERRORS, is_udplite);
546 goto drop_no_sk_drops_inc;
547 }
548
549 return 0;
550drop:
551 atomic_inc(&sk->sk_drops);
552drop_no_sk_drops_inc:
553 UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
554 kfree_skb(skb);
555 return -1;
556}
557
558static struct sock *udp_v6_mcast_next(struct net *net, struct sock *sk,
559 __be16 loc_port, const struct in6_addr *loc_addr,
560 __be16 rmt_port, const struct in6_addr *rmt_addr,
561 int dif)
562{
563 struct hlist_nulls_node *node;
564 struct sock *s = sk;
565 unsigned short num = ntohs(loc_port);
566
567 sk_nulls_for_each_from(s, node) {
568 struct inet_sock *inet = inet_sk(s);
569
570 if (!net_eq(sock_net(s), net))
571 continue;
572
573 if (udp_sk(s)->udp_port_hash == num &&
574 s->sk_family == PF_INET6) {
575 struct ipv6_pinfo *np = inet6_sk(s);
576 if (inet->inet_dport) {
577 if (inet->inet_dport != rmt_port)
578 continue;
579 }
580 if (!ipv6_addr_any(&np->daddr) &&
581 !ipv6_addr_equal(&np->daddr, rmt_addr))
582 continue;
583
584 if (s->sk_bound_dev_if && s->sk_bound_dev_if != dif)
585 continue;
586
587 if (!ipv6_addr_any(&np->rcv_saddr)) {
588 if (!ipv6_addr_equal(&np->rcv_saddr, loc_addr))
589 continue;
590 }
591 if (!inet6_mc_check(s, loc_addr, rmt_addr))
592 continue;
593 return s;
594 }
595 }
596 return NULL;
597}
598
599static void flush_stack(struct sock **stack, unsigned int count,
600 struct sk_buff *skb, unsigned int final)
601{
602 unsigned int i;
603 struct sock *sk;
604 struct sk_buff *skb1;
605
606 for (i = 0; i < count; i++) {
607 skb1 = (i == final) ? skb : skb_clone(skb, GFP_ATOMIC);
608
609 sk = stack[i];
610 if (skb1) {
611 if (sk_rcvqueues_full(sk, skb1)) {
612 kfree_skb(skb1);
613 goto drop;
614 }
615 bh_lock_sock(sk);
616 if (!sock_owned_by_user(sk))
617 udpv6_queue_rcv_skb(sk, skb1);
618 else if (sk_add_backlog(sk, skb1)) {
619 kfree_skb(skb1);
620 bh_unlock_sock(sk);
621 goto drop;
622 }
623 bh_unlock_sock(sk);
624 continue;
625 }
626drop:
627 atomic_inc(&sk->sk_drops);
628 UDP6_INC_STATS_BH(sock_net(sk),
629 UDP_MIB_RCVBUFERRORS, IS_UDPLITE(sk));
630 UDP6_INC_STATS_BH(sock_net(sk),
631 UDP_MIB_INERRORS, IS_UDPLITE(sk));
632 }
633}
634/*
635 * Note: called only from the BH handler context,
636 * so we don't need to lock the hashes.
637 */
638static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
639 const struct in6_addr *saddr, const struct in6_addr *daddr,
640 struct udp_table *udptable)
641{
642 struct sock *sk, *stack[256 / sizeof(struct sock *)];
643 const struct udphdr *uh = udp_hdr(skb);
644 struct udp_hslot *hslot = udp_hashslot(udptable, net, ntohs(uh->dest));
645 int dif;
646 unsigned int i, count = 0;
647
648 spin_lock(&hslot->lock);
649 sk = sk_nulls_head(&hslot->head);
650 dif = inet6_iif(skb);
651 sk = udp_v6_mcast_next(net, sk, uh->dest, daddr, uh->source, saddr, dif);
652 while (sk) {
653 stack[count++] = sk;
654 sk = udp_v6_mcast_next(net, sk_nulls_next(sk), uh->dest, daddr,
655 uh->source, saddr, dif);
656 if (unlikely(count == ARRAY_SIZE(stack))) {
657 if (!sk)
658 break;
659 flush_stack(stack, count, skb, ~0);
660 count = 0;
661 }
662 }
663 /*
664 * before releasing the lock, we must take reference on sockets
665 */
666 for (i = 0; i < count; i++)
667 sock_hold(stack[i]);
668
669 spin_unlock(&hslot->lock);
670
671 if (count) {
672 flush_stack(stack, count, skb, count - 1);
673
674 for (i = 0; i < count; i++)
675 sock_put(stack[i]);
676 } else {
677 kfree_skb(skb);
678 }
679 return 0;
680}
681
682static inline int udp6_csum_init(struct sk_buff *skb, struct udphdr *uh,
683 int proto)
684{
685 int err;
686
687 UDP_SKB_CB(skb)->partial_cov = 0;
688 UDP_SKB_CB(skb)->cscov = skb->len;
689
690 if (proto == IPPROTO_UDPLITE) {
691 err = udplite_checksum_init(skb, uh);
692 if (err)
693 return err;
694 }
695
696 if (uh->check == 0) {
697 /* RFC 2460 section 8.1 says that we SHOULD log
698 this error. Well, it is reasonable.
699 */
700 LIMIT_NETDEBUG(KERN_INFO "IPv6: udp checksum is 0\n");
701 return 1;
702 }
703 if (skb->ip_summed == CHECKSUM_COMPLETE &&
704 !csum_ipv6_magic(&ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
705 skb->len, proto, skb->csum))
706 skb->ip_summed = CHECKSUM_UNNECESSARY;
707
708 if (!skb_csum_unnecessary(skb))
709 skb->csum = ~csum_unfold(csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
710 &ipv6_hdr(skb)->daddr,
711 skb->len, proto, 0));
712
713 return 0;
714}
715
716int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
717 int proto)
718{
719 struct net *net = dev_net(skb->dev);
720 struct sock *sk;
721 struct udphdr *uh;
722 const struct in6_addr *saddr, *daddr;
723 u32 ulen = 0;
724
725 if (!pskb_may_pull(skb, sizeof(struct udphdr)))
726 goto discard;
727
728 saddr = &ipv6_hdr(skb)->saddr;
729 daddr = &ipv6_hdr(skb)->daddr;
730 uh = udp_hdr(skb);
731
732 ulen = ntohs(uh->len);
733 if (ulen > skb->len)
734 goto short_packet;
735
736 if (proto == IPPROTO_UDP) {
737 /* UDP validates ulen. */
738
739 /* Check for jumbo payload */
740 if (ulen == 0)
741 ulen = skb->len;
742
743 if (ulen < sizeof(*uh))
744 goto short_packet;
745
746 if (ulen < skb->len) {
747 if (pskb_trim_rcsum(skb, ulen))
748 goto short_packet;
749 saddr = &ipv6_hdr(skb)->saddr;
750 daddr = &ipv6_hdr(skb)->daddr;
751 uh = udp_hdr(skb);
752 }
753 }
754
755 if (udp6_csum_init(skb, uh, proto))
756 goto discard;
757
758 /*
759 * Multicast receive code
760 */
761 if (ipv6_addr_is_multicast(daddr))
762 return __udp6_lib_mcast_deliver(net, skb,
763 saddr, daddr, udptable);
764
765 /* Unicast */
766
767 /*
768 * check socket cache ... must talk to Alan about his plans
769 * for sock caches... i'll skip this for now.
770 */
771 sk = __udp6_lib_lookup_skb(skb, uh->source, uh->dest, udptable);
772
773 if (sk == NULL) {
774 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
775 goto discard;
776
777 if (udp_lib_checksum_complete(skb))
778 goto discard;
779 UDP6_INC_STATS_BH(net, UDP_MIB_NOPORTS,
780 proto == IPPROTO_UDPLITE);
781
782 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
783
784 kfree_skb(skb);
785 return 0;
786 }
787
788 /* deliver */
789
790 if (sk_rcvqueues_full(sk, skb)) {
791 sock_put(sk);
792 goto discard;
793 }
794 bh_lock_sock(sk);
795 if (!sock_owned_by_user(sk))
796 udpv6_queue_rcv_skb(sk, skb);
797 else if (sk_add_backlog(sk, skb)) {
798 atomic_inc(&sk->sk_drops);
799 bh_unlock_sock(sk);
800 sock_put(sk);
801 goto discard;
802 }
803 bh_unlock_sock(sk);
804 sock_put(sk);
805 return 0;
806
807short_packet:
808 LIMIT_NETDEBUG(KERN_DEBUG "UDP%sv6: short packet: From [%pI6c]:%u %d/%d to [%pI6c]:%u\n",
809 proto == IPPROTO_UDPLITE ? "-Lite" : "",
810 saddr,
811 ntohs(uh->source),
812 ulen,
813 skb->len,
814 daddr,
815 ntohs(uh->dest));
816
817discard:
818 UDP6_INC_STATS_BH(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE);
819 kfree_skb(skb);
820 return 0;
821}
822
823static __inline__ int udpv6_rcv(struct sk_buff *skb)
824{
825 return __udp6_lib_rcv(skb, &udp_table, IPPROTO_UDP);
826}
827
828/*
829 * Throw away all pending data and cancel the corking. Socket is locked.
830 */
831static void udp_v6_flush_pending_frames(struct sock *sk)
832{
833 struct udp_sock *up = udp_sk(sk);
834
835 if (up->pending == AF_INET)
836 udp_flush_pending_frames(sk);
837 else if (up->pending) {
838 up->len = 0;
839 up->pending = 0;
840 ip6_flush_pending_frames(sk);
841 }
842}
843
844/**
845 * udp6_hwcsum_outgoing - handle outgoing HW checksumming
846 * @sk: socket we are sending on
847 * @skb: sk_buff containing the filled-in UDP header
848 * (checksum field must be zeroed out)
849 */
850static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb,
851 const struct in6_addr *saddr,
852 const struct in6_addr *daddr, int len)
853{
854 unsigned int offset;
855 struct udphdr *uh = udp_hdr(skb);
856 __wsum csum = 0;
857
858 if (skb_queue_len(&sk->sk_write_queue) == 1) {
859 /* Only one fragment on the socket. */
860 skb->csum_start = skb_transport_header(skb) - skb->head;
861 skb->csum_offset = offsetof(struct udphdr, check);
862 uh->check = ~csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 0);
863 } else {
864 /*
865 * HW-checksum won't work as there are two or more
866 * fragments on the socket so that all csums of sk_buffs
867 * should be together
868 */
869 offset = skb_transport_offset(skb);
870 skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
871
872 skb->ip_summed = CHECKSUM_NONE;
873
874 skb_queue_walk(&sk->sk_write_queue, skb) {
875 csum = csum_add(csum, skb->csum);
876 }
877
878 uh->check = csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP,
879 csum);
880 if (uh->check == 0)
881 uh->check = CSUM_MANGLED_0;
882 }
883}
884
885/*
886 * Sending
887 */
888
889static int udp_v6_push_pending_frames(struct sock *sk)
890{
891 struct sk_buff *skb;
892 struct udphdr *uh;
893 struct udp_sock *up = udp_sk(sk);
894 struct inet_sock *inet = inet_sk(sk);
895 struct flowi6 *fl6 = &inet->cork.fl.u.ip6;
896 int err = 0;
897 int is_udplite = IS_UDPLITE(sk);
898 __wsum csum = 0;
899
900 /* Grab the skbuff where UDP header space exists. */
901 if ((skb = skb_peek(&sk->sk_write_queue)) == NULL)
902 goto out;
903
904 /*
905 * Create a UDP header
906 */
907 uh = udp_hdr(skb);
908 uh->source = fl6->fl6_sport;
909 uh->dest = fl6->fl6_dport;
910 uh->len = htons(up->len);
911 uh->check = 0;
912
913 if (is_udplite)
914 csum = udplite_csum_outgoing(sk, skb);
915 else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */
916 udp6_hwcsum_outgoing(sk, skb, &fl6->saddr, &fl6->daddr,
917 up->len);
918 goto send;
919 } else
920 csum = udp_csum_outgoing(sk, skb);
921
922 /* add protocol-dependent pseudo-header */
923 uh->check = csum_ipv6_magic(&fl6->saddr, &fl6->daddr,
924 up->len, fl6->flowi6_proto, csum);
925 if (uh->check == 0)
926 uh->check = CSUM_MANGLED_0;
927
928send:
929 err = ip6_push_pending_frames(sk);
930 if (err) {
931 if (err == -ENOBUFS && !inet6_sk(sk)->recverr) {
932 UDP6_INC_STATS_USER(sock_net(sk),
933 UDP_MIB_SNDBUFERRORS, is_udplite);
934 err = 0;
935 }
936 } else
937 UDP6_INC_STATS_USER(sock_net(sk),
938 UDP_MIB_OUTDATAGRAMS, is_udplite);
939out:
940 up->len = 0;
941 up->pending = 0;
942 return err;
943}
944
945int udpv6_sendmsg(struct kiocb *iocb, struct sock *sk,
946 struct msghdr *msg, size_t len)
947{
948 struct ipv6_txoptions opt_space;
949 struct udp_sock *up = udp_sk(sk);
950 struct inet_sock *inet = inet_sk(sk);
951 struct ipv6_pinfo *np = inet6_sk(sk);
952 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) msg->msg_name;
953 struct in6_addr *daddr, *final_p, final;
954 struct ipv6_txoptions *opt = NULL;
955 struct ip6_flowlabel *flowlabel = NULL;
956 struct flowi6 fl6;
957 struct dst_entry *dst;
958 int addr_len = msg->msg_namelen;
959 int ulen = len;
960 int hlimit = -1;
961 int tclass = -1;
962 int dontfrag = -1;
963 int corkreq = up->corkflag || msg->msg_flags&MSG_MORE;
964 int err;
965 int connected = 0;
966 int is_udplite = IS_UDPLITE(sk);
967 int (*getfrag)(void *, char *, int, int, int, struct sk_buff *);
968
969 /* destination address check */
970 if (sin6) {
971 if (addr_len < offsetof(struct sockaddr, sa_data))
972 return -EINVAL;
973
974 switch (sin6->sin6_family) {
975 case AF_INET6:
976 if (addr_len < SIN6_LEN_RFC2133)
977 return -EINVAL;
978 daddr = &sin6->sin6_addr;
979 break;
980 case AF_INET:
981 goto do_udp_sendmsg;
982 case AF_UNSPEC:
983 msg->msg_name = sin6 = NULL;
984 msg->msg_namelen = addr_len = 0;
985 daddr = NULL;
986 break;
987 default:
988 return -EINVAL;
989 }
990 } else if (!up->pending) {
991 if (sk->sk_state != TCP_ESTABLISHED)
992 return -EDESTADDRREQ;
993 daddr = &np->daddr;
994 } else
995 daddr = NULL;
996
997 if (daddr) {
998 if (ipv6_addr_v4mapped(daddr)) {
999 struct sockaddr_in sin;
1000 sin.sin_family = AF_INET;
1001 sin.sin_port = sin6 ? sin6->sin6_port : inet->inet_dport;
1002 sin.sin_addr.s_addr = daddr->s6_addr32[3];
1003 msg->msg_name = &sin;
1004 msg->msg_namelen = sizeof(sin);
1005do_udp_sendmsg:
1006 if (__ipv6_only_sock(sk))
1007 return -ENETUNREACH;
1008 return udp_sendmsg(iocb, sk, msg, len);
1009 }
1010 }
1011
1012 if (up->pending == AF_INET)
1013 return udp_sendmsg(iocb, sk, msg, len);
1014
1015 /* Rough check on arithmetic overflow,
1016 better check is made in ip6_append_data().
1017 */
1018 if (len > INT_MAX - sizeof(struct udphdr))
1019 return -EMSGSIZE;
1020
1021 if (up->pending) {
1022 /*
1023 * There are pending frames.
1024 * The socket lock must be held while it's corked.
1025 */
1026 lock_sock(sk);
1027 if (likely(up->pending)) {
1028 if (unlikely(up->pending != AF_INET6)) {
1029 release_sock(sk);
1030 return -EAFNOSUPPORT;
1031 }
1032 dst = NULL;
1033 goto do_append_data;
1034 }
1035 release_sock(sk);
1036 }
1037 ulen += sizeof(struct udphdr);
1038
1039 memset(&fl6, 0, sizeof(fl6));
1040
1041 if (sin6) {
1042 if (sin6->sin6_port == 0)
1043 return -EINVAL;
1044
1045 fl6.fl6_dport = sin6->sin6_port;
1046 daddr = &sin6->sin6_addr;
1047
1048 if (np->sndflow) {
1049 fl6.flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK;
1050 if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) {
1051 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1052 if (flowlabel == NULL)
1053 return -EINVAL;
1054 daddr = &flowlabel->dst;
1055 }
1056 }
1057
1058 /*
1059 * Otherwise it will be difficult to maintain
1060 * sk->sk_dst_cache.
1061 */
1062 if (sk->sk_state == TCP_ESTABLISHED &&
1063 ipv6_addr_equal(daddr, &np->daddr))
1064 daddr = &np->daddr;
1065
1066 if (addr_len >= sizeof(struct sockaddr_in6) &&
1067 sin6->sin6_scope_id &&
1068 ipv6_addr_type(daddr)&IPV6_ADDR_LINKLOCAL)
1069 fl6.flowi6_oif = sin6->sin6_scope_id;
1070 } else {
1071 if (sk->sk_state != TCP_ESTABLISHED)
1072 return -EDESTADDRREQ;
1073
1074 fl6.fl6_dport = inet->inet_dport;
1075 daddr = &np->daddr;
1076 fl6.flowlabel = np->flow_label;
1077 connected = 1;
1078 }
1079
1080 if (!fl6.flowi6_oif)
1081 fl6.flowi6_oif = sk->sk_bound_dev_if;
1082
1083 if (!fl6.flowi6_oif)
1084 fl6.flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;
1085
1086 fl6.flowi6_mark = sk->sk_mark;
1087
1088 if (msg->msg_controllen) {
1089 opt = &opt_space;
1090 memset(opt, 0, sizeof(struct ipv6_txoptions));
1091 opt->tot_len = sizeof(*opt);
1092
1093 err = datagram_send_ctl(sock_net(sk), sk, msg, &fl6, opt,
1094 &hlimit, &tclass, &dontfrag);
1095 if (err < 0) {
1096 fl6_sock_release(flowlabel);
1097 return err;
1098 }
1099 if ((fl6.flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) {
1100 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1101 if (flowlabel == NULL)
1102 return -EINVAL;
1103 }
1104 if (!(opt->opt_nflen|opt->opt_flen))
1105 opt = NULL;
1106 connected = 0;
1107 }
1108 if (opt == NULL)
1109 opt = np->opt;
1110 if (flowlabel)
1111 opt = fl6_merge_options(&opt_space, flowlabel, opt);
1112 opt = ipv6_fixup_options(&opt_space, opt);
1113
1114 fl6.flowi6_proto = sk->sk_protocol;
1115 if (!ipv6_addr_any(daddr))
1116 ipv6_addr_copy(&fl6.daddr, daddr);
1117 else
1118 fl6.daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */
1119 if (ipv6_addr_any(&fl6.saddr) && !ipv6_addr_any(&np->saddr))
1120 ipv6_addr_copy(&fl6.saddr, &np->saddr);
1121 fl6.fl6_sport = inet->inet_sport;
1122
1123 final_p = fl6_update_dst(&fl6, opt, &final);
1124 if (final_p)
1125 connected = 0;
1126
1127 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr)) {
1128 fl6.flowi6_oif = np->mcast_oif;
1129 connected = 0;
1130 }
1131
1132 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
1133
1134 dst = ip6_sk_dst_lookup_flow(sk, &fl6, final_p, true);
1135 if (IS_ERR(dst)) {
1136 err = PTR_ERR(dst);
1137 dst = NULL;
1138 goto out;
1139 }
1140
1141 if (hlimit < 0) {
1142 if (ipv6_addr_is_multicast(&fl6.daddr))
1143 hlimit = np->mcast_hops;
1144 else
1145 hlimit = np->hop_limit;
1146 if (hlimit < 0)
1147 hlimit = ip6_dst_hoplimit(dst);
1148 }
1149
1150 if (tclass < 0)
1151 tclass = np->tclass;
1152
1153 if (dontfrag < 0)
1154 dontfrag = np->dontfrag;
1155
1156 if (msg->msg_flags&MSG_CONFIRM)
1157 goto do_confirm;
1158back_from_confirm:
1159
1160 lock_sock(sk);
1161 if (unlikely(up->pending)) {
1162 /* The socket is already corked while preparing it. */
1163 /* ... which is an evident application bug. --ANK */
1164 release_sock(sk);
1165
1166 LIMIT_NETDEBUG(KERN_DEBUG "udp cork app bug 2\n");
1167 err = -EINVAL;
1168 goto out;
1169 }
1170
1171 up->pending = AF_INET6;
1172
1173do_append_data:
1174 up->len += ulen;
1175 getfrag = is_udplite ? udplite_getfrag : ip_generic_getfrag;
1176 err = ip6_append_data(sk, getfrag, msg->msg_iov, ulen,
1177 sizeof(struct udphdr), hlimit, tclass, opt, &fl6,
1178 (struct rt6_info*)dst,
1179 corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags, dontfrag);
1180 if (err)
1181 udp_v6_flush_pending_frames(sk);
1182 else if (!corkreq)
1183 err = udp_v6_push_pending_frames(sk);
1184 else if (unlikely(skb_queue_empty(&sk->sk_write_queue)))
1185 up->pending = 0;
1186
1187 if (dst) {
1188 if (connected) {
1189 ip6_dst_store(sk, dst,
1190 ipv6_addr_equal(&fl6.daddr, &np->daddr) ?
1191 &np->daddr : NULL,
1192#ifdef CONFIG_IPV6_SUBTREES
1193 ipv6_addr_equal(&fl6.saddr, &np->saddr) ?
1194 &np->saddr :
1195#endif
1196 NULL);
1197 } else {
1198 dst_release(dst);
1199 }
1200 dst = NULL;
1201 }
1202
1203 if (err > 0)
1204 err = np->recverr ? net_xmit_errno(err) : 0;
1205 release_sock(sk);
1206out:
1207 dst_release(dst);
1208 fl6_sock_release(flowlabel);
1209 if (!err)
1210 return len;
1211 /*
1212 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space. Reporting
1213 * ENOBUFS might not be good (it's not tunable per se), but otherwise
1214 * we don't have a good statistic (IpOutDiscards but it can be too many
1215 * things). We could add another new stat but at least for now that
1216 * seems like overkill.
1217 */
1218 if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) {
1219 UDP6_INC_STATS_USER(sock_net(sk),
1220 UDP_MIB_SNDBUFERRORS, is_udplite);
1221 }
1222 return err;
1223
1224do_confirm:
1225 dst_confirm(dst);
1226 if (!(msg->msg_flags&MSG_PROBE) || len)
1227 goto back_from_confirm;
1228 err = 0;
1229 goto out;
1230}
1231
1232void udpv6_destroy_sock(struct sock *sk)
1233{
1234 lock_sock(sk);
1235 udp_v6_flush_pending_frames(sk);
1236 release_sock(sk);
1237
1238 inet6_destroy_sock(sk);
1239}
1240
1241/*
1242 * Socket option code for UDP
1243 */
1244int udpv6_setsockopt(struct sock *sk, int level, int optname,
1245 char __user *optval, unsigned int optlen)
1246{
1247 if (level == SOL_UDP || level == SOL_UDPLITE)
1248 return udp_lib_setsockopt(sk, level, optname, optval, optlen,
1249 udp_v6_push_pending_frames);
1250 return ipv6_setsockopt(sk, level, optname, optval, optlen);
1251}
1252
1253#ifdef CONFIG_COMPAT
1254int compat_udpv6_setsockopt(struct sock *sk, int level, int optname,
1255 char __user *optval, unsigned int optlen)
1256{
1257 if (level == SOL_UDP || level == SOL_UDPLITE)
1258 return udp_lib_setsockopt(sk, level, optname, optval, optlen,
1259 udp_v6_push_pending_frames);
1260 return compat_ipv6_setsockopt(sk, level, optname, optval, optlen);
1261}
1262#endif
1263
1264int udpv6_getsockopt(struct sock *sk, int level, int optname,
1265 char __user *optval, int __user *optlen)
1266{
1267 if (level == SOL_UDP || level == SOL_UDPLITE)
1268 return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1269 return ipv6_getsockopt(sk, level, optname, optval, optlen);
1270}
1271
1272#ifdef CONFIG_COMPAT
1273int compat_udpv6_getsockopt(struct sock *sk, int level, int optname,
1274 char __user *optval, int __user *optlen)
1275{
1276 if (level == SOL_UDP || level == SOL_UDPLITE)
1277 return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1278 return compat_ipv6_getsockopt(sk, level, optname, optval, optlen);
1279}
1280#endif
1281
1282static int udp6_ufo_send_check(struct sk_buff *skb)
1283{
1284 const struct ipv6hdr *ipv6h;
1285 struct udphdr *uh;
1286
1287 if (!pskb_may_pull(skb, sizeof(*uh)))
1288 return -EINVAL;
1289
1290 ipv6h = ipv6_hdr(skb);
1291 uh = udp_hdr(skb);
1292
1293 uh->check = ~csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr, skb->len,
1294 IPPROTO_UDP, 0);
1295 skb->csum_start = skb_transport_header(skb) - skb->head;
1296 skb->csum_offset = offsetof(struct udphdr, check);
1297 skb->ip_summed = CHECKSUM_PARTIAL;
1298 return 0;
1299}
1300
1301static struct sk_buff *udp6_ufo_fragment(struct sk_buff *skb, u32 features)
1302{
1303 struct sk_buff *segs = ERR_PTR(-EINVAL);
1304 unsigned int mss;
1305 unsigned int unfrag_ip6hlen, unfrag_len;
1306 struct frag_hdr *fptr;
1307 u8 *mac_start, *prevhdr;
1308 u8 nexthdr;
1309 u8 frag_hdr_sz = sizeof(struct frag_hdr);
1310 int offset;
1311 __wsum csum;
1312
1313 mss = skb_shinfo(skb)->gso_size;
1314 if (unlikely(skb->len <= mss))
1315 goto out;
1316
1317 if (skb_gso_ok(skb, features | NETIF_F_GSO_ROBUST)) {
1318 /* Packet is from an untrusted source, reset gso_segs. */
1319 int type = skb_shinfo(skb)->gso_type;
1320
1321 if (unlikely(type & ~(SKB_GSO_UDP | SKB_GSO_DODGY) ||
1322 !(type & (SKB_GSO_UDP))))
1323 goto out;
1324
1325 skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(skb->len, mss);
1326
1327 segs = NULL;
1328 goto out;
1329 }
1330
1331 /* Do software UFO. Complete and fill in the UDP checksum as HW cannot
1332 * do checksum of UDP packets sent as multiple IP fragments.
1333 */
1334 offset = skb_checksum_start_offset(skb);
1335 csum = skb_checksum(skb, offset, skb->len- offset, 0);
1336 offset += skb->csum_offset;
1337 *(__sum16 *)(skb->data + offset) = csum_fold(csum);
1338 skb->ip_summed = CHECKSUM_NONE;
1339
1340 /* Check if there is enough headroom to insert fragment header. */
1341 if ((skb_mac_header(skb) < skb->head + frag_hdr_sz) &&
1342 pskb_expand_head(skb, frag_hdr_sz, 0, GFP_ATOMIC))
1343 goto out;
1344
1345 /* Find the unfragmentable header and shift it left by frag_hdr_sz
1346 * bytes to insert fragment header.
1347 */
1348 unfrag_ip6hlen = ip6_find_1stfragopt(skb, &prevhdr);
1349 nexthdr = *prevhdr;
1350 *prevhdr = NEXTHDR_FRAGMENT;
1351 unfrag_len = skb_network_header(skb) - skb_mac_header(skb) +
1352 unfrag_ip6hlen;
1353 mac_start = skb_mac_header(skb);
1354 memmove(mac_start-frag_hdr_sz, mac_start, unfrag_len);
1355
1356 skb->mac_header -= frag_hdr_sz;
1357 skb->network_header -= frag_hdr_sz;
1358
1359 fptr = (struct frag_hdr *)(skb_network_header(skb) + unfrag_ip6hlen);
1360 fptr->nexthdr = nexthdr;
1361 fptr->reserved = 0;
1362 ipv6_select_ident(fptr, (struct rt6_info *)skb_dst(skb));
1363
1364 /* Fragment the skb. ipv6 header and the remaining fields of the
1365 * fragment header are updated in ipv6_gso_segment()
1366 */
1367 segs = skb_segment(skb, features);
1368
1369out:
1370 return segs;
1371}
1372
1373static const struct inet6_protocol udpv6_protocol = {
1374 .handler = udpv6_rcv,
1375 .err_handler = udpv6_err,
1376 .gso_send_check = udp6_ufo_send_check,
1377 .gso_segment = udp6_ufo_fragment,
1378 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1379};
1380
1381/* ------------------------------------------------------------------------ */
1382#ifdef CONFIG_PROC_FS
1383
1384static void udp6_sock_seq_show(struct seq_file *seq, struct sock *sp, int bucket)
1385{
1386 struct inet_sock *inet = inet_sk(sp);
1387 struct ipv6_pinfo *np = inet6_sk(sp);
1388 const struct in6_addr *dest, *src;
1389 __u16 destp, srcp;
1390
1391 dest = &np->daddr;
1392 src = &np->rcv_saddr;
1393 destp = ntohs(inet->inet_dport);
1394 srcp = ntohs(inet->inet_sport);
1395 seq_printf(seq,
1396 "%5d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1397 "%02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %pK %d\n",
1398 bucket,
1399 src->s6_addr32[0], src->s6_addr32[1],
1400 src->s6_addr32[2], src->s6_addr32[3], srcp,
1401 dest->s6_addr32[0], dest->s6_addr32[1],
1402 dest->s6_addr32[2], dest->s6_addr32[3], destp,
1403 sp->sk_state,
1404 sk_wmem_alloc_get(sp),
1405 sk_rmem_alloc_get(sp),
1406 0, 0L, 0,
1407 sock_i_uid(sp), 0,
1408 sock_i_ino(sp),
1409 atomic_read(&sp->sk_refcnt), sp,
1410 atomic_read(&sp->sk_drops));
1411}
1412
1413int udp6_seq_show(struct seq_file *seq, void *v)
1414{
1415 if (v == SEQ_START_TOKEN)
1416 seq_printf(seq,
1417 " sl "
1418 "local_address "
1419 "remote_address "
1420 "st tx_queue rx_queue tr tm->when retrnsmt"
1421 " uid timeout inode ref pointer drops\n");
1422 else
1423 udp6_sock_seq_show(seq, v, ((struct udp_iter_state *)seq->private)->bucket);
1424 return 0;
1425}
1426
1427static struct udp_seq_afinfo udp6_seq_afinfo = {
1428 .name = "udp6",
1429 .family = AF_INET6,
1430 .udp_table = &udp_table,
1431 .seq_fops = {
1432 .owner = THIS_MODULE,
1433 },
1434 .seq_ops = {
1435 .show = udp6_seq_show,
1436 },
1437};
1438
1439int __net_init udp6_proc_init(struct net *net)
1440{
1441 return udp_proc_register(net, &udp6_seq_afinfo);
1442}
1443
1444void udp6_proc_exit(struct net *net) {
1445 udp_proc_unregister(net, &udp6_seq_afinfo);
1446}
1447#endif /* CONFIG_PROC_FS */
1448
1449/* ------------------------------------------------------------------------ */
1450
1451struct proto udpv6_prot = {
1452 .name = "UDPv6",
1453 .owner = THIS_MODULE,
1454 .close = udp_lib_close,
1455 .connect = ip6_datagram_connect,
1456 .disconnect = udp_disconnect,
1457 .ioctl = udp_ioctl,
1458 .destroy = udpv6_destroy_sock,
1459 .setsockopt = udpv6_setsockopt,
1460 .getsockopt = udpv6_getsockopt,
1461 .sendmsg = udpv6_sendmsg,
1462 .recvmsg = udpv6_recvmsg,
1463 .backlog_rcv = udpv6_queue_rcv_skb,
1464 .hash = udp_lib_hash,
1465 .unhash = udp_lib_unhash,
1466 .rehash = udp_v6_rehash,
1467 .get_port = udp_v6_get_port,
1468 .memory_allocated = &udp_memory_allocated,
1469 .sysctl_mem = sysctl_udp_mem,
1470 .sysctl_wmem = &sysctl_udp_wmem_min,
1471 .sysctl_rmem = &sysctl_udp_rmem_min,
1472 .obj_size = sizeof(struct udp6_sock),
1473 .slab_flags = SLAB_DESTROY_BY_RCU,
1474 .h.udp_table = &udp_table,
1475#ifdef CONFIG_COMPAT
1476 .compat_setsockopt = compat_udpv6_setsockopt,
1477 .compat_getsockopt = compat_udpv6_getsockopt,
1478#endif
1479 .clear_sk = sk_prot_clear_portaddr_nulls,
1480};
1481
1482static struct inet_protosw udpv6_protosw = {
1483 .type = SOCK_DGRAM,
1484 .protocol = IPPROTO_UDP,
1485 .prot = &udpv6_prot,
1486 .ops = &inet6_dgram_ops,
1487 .no_check = UDP_CSUM_DEFAULT,
1488 .flags = INET_PROTOSW_PERMANENT,
1489};
1490
1491
1492int __init udpv6_init(void)
1493{
1494 int ret;
1495
1496 ret = inet6_add_protocol(&udpv6_protocol, IPPROTO_UDP);
1497 if (ret)
1498 goto out;
1499
1500 ret = inet6_register_protosw(&udpv6_protosw);
1501 if (ret)
1502 goto out_udpv6_protocol;
1503out:
1504 return ret;
1505
1506out_udpv6_protocol:
1507 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1508 goto out;
1509}
1510
1511void udpv6_exit(void)
1512{
1513 inet6_unregister_protosw(&udpv6_protosw);
1514 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1515}