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
ipv6_rcv_saddr_equal(const struct sock * sk,const struct sock * sk2)53 int 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
udp6_portaddr_hash(struct net * net,const struct in6_addr * addr6,unsigned int port)85 static 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
udp_v6_get_port(struct sock * sk,unsigned short snum)102 int 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
udp_v6_rehash(struct sock * sk)114 static 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
compute_score(struct sock * sk,struct net * net,unsigned short hnum,const struct in6_addr * saddr,__be16 sport,const struct in6_addr * daddr,__be16 dport,int dif)123 static 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)
compute_score2(struct sock * sk,struct net * net,const struct in6_addr * saddr,__be16 sport,const struct in6_addr * daddr,unsigned short hnum,int dif)162 static 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() */
udp6_lib_lookup2(struct net * net,const struct in6_addr * saddr,__be16 sport,const struct in6_addr * daddr,unsigned int hnum,int dif,struct udp_hslot * hslot2,unsigned int slot2)198 static 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
207 begin:
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) {
229 exact_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
__udp6_lib_lookup(struct net * net,const struct in6_addr * saddr,__be16 sport,const struct in6_addr * daddr,__be16 dport,int dif,struct udp_table * udptable)241 static 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 }
278 begin:
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
__udp6_lib_lookup_skb(struct sk_buff * skb,__be16 sport,__be16 dport,struct udp_table * udptable)309 static 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 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
udp6_lib_lookup(struct net * net,const struct in6_addr * saddr,__be16 sport,const struct in6_addr * daddr,__be16 dport,int dif)323 struct 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 }
328 EXPORT_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
udpv6_recvmsg(struct kiocb * iocb,struct sock * sk,struct msghdr * msg,size_t len,int noblock,int flags,int * addr_len)336 int 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
359 try_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
439 out_free:
440 skb_free_datagram_locked(sk, skb);
441 out:
442 return err;
443
444 csum_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 (flags & MSG_DONTWAIT)
457 return -EAGAIN;
458 goto try_again;
459 }
460
__udp6_lib_err(struct sk_buff * skb,struct inet6_skb_parm * opt,u8 type,u8 code,int offset,__be32 info,struct udp_table * udptable)461 void __udp6_lib_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
462 u8 type, u8 code, int offset, __be32 info,
463 struct udp_table *udptable)
464 {
465 struct ipv6_pinfo *np;
466 struct ipv6hdr *hdr = (struct ipv6hdr*)skb->data;
467 struct in6_addr *saddr = &hdr->saddr;
468 struct in6_addr *daddr = &hdr->daddr;
469 struct udphdr *uh = (struct udphdr*)(skb->data+offset);
470 struct sock *sk;
471 int err;
472
473 sk = __udp6_lib_lookup(dev_net(skb->dev), daddr, uh->dest,
474 saddr, uh->source, inet6_iif(skb), udptable);
475 if (sk == NULL)
476 return;
477
478 np = inet6_sk(sk);
479
480 if (!icmpv6_err_convert(type, code, &err) && !np->recverr)
481 goto out;
482
483 if (sk->sk_state != TCP_ESTABLISHED && !np->recverr)
484 goto out;
485
486 if (np->recverr)
487 ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1));
488
489 sk->sk_err = err;
490 sk->sk_error_report(sk);
491 out:
492 sock_put(sk);
493 }
494
udpv6_err(struct sk_buff * skb,struct inet6_skb_parm * opt,u8 type,u8 code,int offset,__be32 info)495 static __inline__ void udpv6_err(struct sk_buff *skb,
496 struct inet6_skb_parm *opt, u8 type,
497 u8 code, int offset, __be32 info )
498 {
499 __udp6_lib_err(skb, opt, type, code, offset, info, &udp_table);
500 }
501
udpv6_queue_rcv_skb(struct sock * sk,struct sk_buff * skb)502 int udpv6_queue_rcv_skb(struct sock * sk, struct sk_buff *skb)
503 {
504 struct udp_sock *up = udp_sk(sk);
505 int rc;
506 int is_udplite = IS_UDPLITE(sk);
507
508 if (!ipv6_addr_any(&inet6_sk(sk)->daddr))
509 sock_rps_save_rxhash(sk, skb->rxhash);
510
511 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
512 goto drop;
513
514 /*
515 * UDP-Lite specific tests, ignored on UDP sockets (see net/ipv4/udp.c).
516 */
517 if ((is_udplite & UDPLITE_RECV_CC) && UDP_SKB_CB(skb)->partial_cov) {
518
519 if (up->pcrlen == 0) { /* full coverage was set */
520 LIMIT_NETDEBUG(KERN_WARNING "UDPLITE6: partial coverage"
521 " %d while full coverage %d requested\n",
522 UDP_SKB_CB(skb)->cscov, skb->len);
523 goto drop;
524 }
525 if (UDP_SKB_CB(skb)->cscov < up->pcrlen) {
526 LIMIT_NETDEBUG(KERN_WARNING "UDPLITE6: coverage %d "
527 "too small, need min %d\n",
528 UDP_SKB_CB(skb)->cscov, up->pcrlen);
529 goto drop;
530 }
531 }
532
533 if (rcu_dereference_raw(sk->sk_filter)) {
534 if (udp_lib_checksum_complete(skb))
535 goto drop;
536 }
537
538 if ((rc = ip_queue_rcv_skb(sk, skb)) < 0) {
539 /* Note that an ENOMEM error is charged twice */
540 if (rc == -ENOMEM)
541 UDP6_INC_STATS_BH(sock_net(sk),
542 UDP_MIB_RCVBUFERRORS, is_udplite);
543 goto drop_no_sk_drops_inc;
544 }
545
546 return 0;
547 drop:
548 atomic_inc(&sk->sk_drops);
549 drop_no_sk_drops_inc:
550 UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
551 kfree_skb(skb);
552 return -1;
553 }
554
udp_v6_mcast_next(struct net * net,struct sock * sk,__be16 loc_port,struct in6_addr * loc_addr,__be16 rmt_port,struct in6_addr * rmt_addr,int dif)555 static struct sock *udp_v6_mcast_next(struct net *net, struct sock *sk,
556 __be16 loc_port, struct in6_addr *loc_addr,
557 __be16 rmt_port, struct in6_addr *rmt_addr,
558 int dif)
559 {
560 struct hlist_nulls_node *node;
561 struct sock *s = sk;
562 unsigned short num = ntohs(loc_port);
563
564 sk_nulls_for_each_from(s, node) {
565 struct inet_sock *inet = inet_sk(s);
566
567 if (!net_eq(sock_net(s), net))
568 continue;
569
570 if (udp_sk(s)->udp_port_hash == num &&
571 s->sk_family == PF_INET6) {
572 struct ipv6_pinfo *np = inet6_sk(s);
573 if (inet->inet_dport) {
574 if (inet->inet_dport != rmt_port)
575 continue;
576 }
577 if (!ipv6_addr_any(&np->daddr) &&
578 !ipv6_addr_equal(&np->daddr, rmt_addr))
579 continue;
580
581 if (s->sk_bound_dev_if && s->sk_bound_dev_if != dif)
582 continue;
583
584 if (!ipv6_addr_any(&np->rcv_saddr)) {
585 if (!ipv6_addr_equal(&np->rcv_saddr, loc_addr))
586 continue;
587 }
588 if (!inet6_mc_check(s, loc_addr, rmt_addr))
589 continue;
590 return s;
591 }
592 }
593 return NULL;
594 }
595
flush_stack(struct sock ** stack,unsigned int count,struct sk_buff * skb,unsigned int final)596 static void flush_stack(struct sock **stack, unsigned int count,
597 struct sk_buff *skb, unsigned int final)
598 {
599 unsigned int i;
600 struct sock *sk;
601 struct sk_buff *skb1;
602
603 for (i = 0; i < count; i++) {
604 skb1 = (i == final) ? skb : skb_clone(skb, GFP_ATOMIC);
605
606 sk = stack[i];
607 if (skb1) {
608 if (sk_rcvqueues_full(sk, skb1)) {
609 kfree_skb(skb1);
610 goto drop;
611 }
612 bh_lock_sock(sk);
613 if (!sock_owned_by_user(sk))
614 udpv6_queue_rcv_skb(sk, skb1);
615 else if (sk_add_backlog(sk, skb1)) {
616 kfree_skb(skb1);
617 bh_unlock_sock(sk);
618 goto drop;
619 }
620 bh_unlock_sock(sk);
621 continue;
622 }
623 drop:
624 atomic_inc(&sk->sk_drops);
625 UDP6_INC_STATS_BH(sock_net(sk),
626 UDP_MIB_RCVBUFERRORS, IS_UDPLITE(sk));
627 UDP6_INC_STATS_BH(sock_net(sk),
628 UDP_MIB_INERRORS, IS_UDPLITE(sk));
629 }
630 }
631 /*
632 * Note: called only from the BH handler context,
633 * so we don't need to lock the hashes.
634 */
__udp6_lib_mcast_deliver(struct net * net,struct sk_buff * skb,struct in6_addr * saddr,struct in6_addr * daddr,struct udp_table * udptable)635 static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
636 struct in6_addr *saddr, struct in6_addr *daddr,
637 struct udp_table *udptable)
638 {
639 struct sock *sk, *stack[256 / sizeof(struct sock *)];
640 const struct udphdr *uh = udp_hdr(skb);
641 struct udp_hslot *hslot = udp_hashslot(udptable, net, ntohs(uh->dest));
642 int dif;
643 unsigned int i, count = 0;
644
645 spin_lock(&hslot->lock);
646 sk = sk_nulls_head(&hslot->head);
647 dif = inet6_iif(skb);
648 sk = udp_v6_mcast_next(net, sk, uh->dest, daddr, uh->source, saddr, dif);
649 while (sk) {
650 stack[count++] = sk;
651 sk = udp_v6_mcast_next(net, sk_nulls_next(sk), uh->dest, daddr,
652 uh->source, saddr, dif);
653 if (unlikely(count == ARRAY_SIZE(stack))) {
654 if (!sk)
655 break;
656 flush_stack(stack, count, skb, ~0);
657 count = 0;
658 }
659 }
660 /*
661 * before releasing the lock, we must take reference on sockets
662 */
663 for (i = 0; i < count; i++)
664 sock_hold(stack[i]);
665
666 spin_unlock(&hslot->lock);
667
668 if (count) {
669 flush_stack(stack, count, skb, count - 1);
670
671 for (i = 0; i < count; i++)
672 sock_put(stack[i]);
673 } else {
674 kfree_skb(skb);
675 }
676 return 0;
677 }
678
udp6_csum_init(struct sk_buff * skb,struct udphdr * uh,int proto)679 static inline int udp6_csum_init(struct sk_buff *skb, struct udphdr *uh,
680 int proto)
681 {
682 int err;
683
684 UDP_SKB_CB(skb)->partial_cov = 0;
685 UDP_SKB_CB(skb)->cscov = skb->len;
686
687 if (proto == IPPROTO_UDPLITE) {
688 err = udplite_checksum_init(skb, uh);
689 if (err)
690 return err;
691 }
692
693 if (uh->check == 0) {
694 /* RFC 2460 section 8.1 says that we SHOULD log
695 this error. Well, it is reasonable.
696 */
697 LIMIT_NETDEBUG(KERN_INFO "IPv6: udp checksum is 0\n");
698 return 1;
699 }
700 if (skb->ip_summed == CHECKSUM_COMPLETE &&
701 !csum_ipv6_magic(&ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
702 skb->len, proto, skb->csum))
703 skb->ip_summed = CHECKSUM_UNNECESSARY;
704
705 if (!skb_csum_unnecessary(skb))
706 skb->csum = ~csum_unfold(csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
707 &ipv6_hdr(skb)->daddr,
708 skb->len, proto, 0));
709
710 return 0;
711 }
712
__udp6_lib_rcv(struct sk_buff * skb,struct udp_table * udptable,int proto)713 int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
714 int proto)
715 {
716 struct net *net = dev_net(skb->dev);
717 struct sock *sk;
718 struct udphdr *uh;
719 struct in6_addr *saddr, *daddr;
720 u32 ulen = 0;
721
722 if (!pskb_may_pull(skb, sizeof(struct udphdr)))
723 goto discard;
724
725 saddr = &ipv6_hdr(skb)->saddr;
726 daddr = &ipv6_hdr(skb)->daddr;
727 uh = udp_hdr(skb);
728
729 ulen = ntohs(uh->len);
730 if (ulen > skb->len)
731 goto short_packet;
732
733 if (proto == IPPROTO_UDP) {
734 /* UDP validates ulen. */
735
736 /* Check for jumbo payload */
737 if (ulen == 0)
738 ulen = skb->len;
739
740 if (ulen < sizeof(*uh))
741 goto short_packet;
742
743 if (ulen < skb->len) {
744 if (pskb_trim_rcsum(skb, ulen))
745 goto short_packet;
746 saddr = &ipv6_hdr(skb)->saddr;
747 daddr = &ipv6_hdr(skb)->daddr;
748 uh = udp_hdr(skb);
749 }
750 }
751
752 if (udp6_csum_init(skb, uh, proto))
753 goto discard;
754
755 /*
756 * Multicast receive code
757 */
758 if (ipv6_addr_is_multicast(daddr))
759 return __udp6_lib_mcast_deliver(net, skb,
760 saddr, daddr, udptable);
761
762 /* Unicast */
763
764 /*
765 * check socket cache ... must talk to Alan about his plans
766 * for sock caches... i'll skip this for now.
767 */
768 sk = __udp6_lib_lookup_skb(skb, uh->source, uh->dest, udptable);
769
770 if (sk == NULL) {
771 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
772 goto discard;
773
774 if (udp_lib_checksum_complete(skb))
775 goto discard;
776 UDP6_INC_STATS_BH(net, UDP_MIB_NOPORTS,
777 proto == IPPROTO_UDPLITE);
778
779 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
780
781 kfree_skb(skb);
782 return 0;
783 }
784
785 /* deliver */
786
787 if (sk_rcvqueues_full(sk, skb)) {
788 sock_put(sk);
789 goto discard;
790 }
791 bh_lock_sock(sk);
792 if (!sock_owned_by_user(sk))
793 udpv6_queue_rcv_skb(sk, skb);
794 else if (sk_add_backlog(sk, skb)) {
795 atomic_inc(&sk->sk_drops);
796 bh_unlock_sock(sk);
797 sock_put(sk);
798 goto discard;
799 }
800 bh_unlock_sock(sk);
801 sock_put(sk);
802 return 0;
803
804 short_packet:
805 LIMIT_NETDEBUG(KERN_DEBUG "UDP%sv6: short packet: From [%pI6c]:%u %d/%d to [%pI6c]:%u\n",
806 proto == IPPROTO_UDPLITE ? "-Lite" : "",
807 saddr,
808 ntohs(uh->source),
809 ulen,
810 skb->len,
811 daddr,
812 ntohs(uh->dest));
813
814 discard:
815 UDP6_INC_STATS_BH(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE);
816 kfree_skb(skb);
817 return 0;
818 }
819
udpv6_rcv(struct sk_buff * skb)820 static __inline__ int udpv6_rcv(struct sk_buff *skb)
821 {
822 return __udp6_lib_rcv(skb, &udp_table, IPPROTO_UDP);
823 }
824
825 /*
826 * Throw away all pending data and cancel the corking. Socket is locked.
827 */
udp_v6_flush_pending_frames(struct sock * sk)828 static void udp_v6_flush_pending_frames(struct sock *sk)
829 {
830 struct udp_sock *up = udp_sk(sk);
831
832 if (up->pending == AF_INET)
833 udp_flush_pending_frames(sk);
834 else if (up->pending) {
835 up->len = 0;
836 up->pending = 0;
837 ip6_flush_pending_frames(sk);
838 }
839 }
840
841 /**
842 * udp6_hwcsum_outgoing - handle outgoing HW checksumming
843 * @sk: socket we are sending on
844 * @skb: sk_buff containing the filled-in UDP header
845 * (checksum field must be zeroed out)
846 */
udp6_hwcsum_outgoing(struct sock * sk,struct sk_buff * skb,const struct in6_addr * saddr,const struct in6_addr * daddr,int len)847 static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb,
848 const struct in6_addr *saddr,
849 const struct in6_addr *daddr, int len)
850 {
851 unsigned int offset;
852 struct udphdr *uh = udp_hdr(skb);
853 __wsum csum = 0;
854
855 if (skb_queue_len(&sk->sk_write_queue) == 1) {
856 /* Only one fragment on the socket. */
857 skb->csum_start = skb_transport_header(skb) - skb->head;
858 skb->csum_offset = offsetof(struct udphdr, check);
859 uh->check = ~csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 0);
860 } else {
861 /*
862 * HW-checksum won't work as there are two or more
863 * fragments on the socket so that all csums of sk_buffs
864 * should be together
865 */
866 offset = skb_transport_offset(skb);
867 skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
868
869 skb->ip_summed = CHECKSUM_NONE;
870
871 skb_queue_walk(&sk->sk_write_queue, skb) {
872 csum = csum_add(csum, skb->csum);
873 }
874
875 uh->check = csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP,
876 csum);
877 if (uh->check == 0)
878 uh->check = CSUM_MANGLED_0;
879 }
880 }
881
882 /*
883 * Sending
884 */
885
udp_v6_push_pending_frames(struct sock * sk)886 static int udp_v6_push_pending_frames(struct sock *sk)
887 {
888 struct sk_buff *skb;
889 struct udphdr *uh;
890 struct udp_sock *up = udp_sk(sk);
891 struct inet_sock *inet = inet_sk(sk);
892 struct flowi6 *fl6 = &inet->cork.fl.u.ip6;
893 int err = 0;
894 int is_udplite = IS_UDPLITE(sk);
895 __wsum csum = 0;
896
897 /* Grab the skbuff where UDP header space exists. */
898 if ((skb = skb_peek(&sk->sk_write_queue)) == NULL)
899 goto out;
900
901 /*
902 * Create a UDP header
903 */
904 uh = udp_hdr(skb);
905 uh->source = fl6->fl6_sport;
906 uh->dest = fl6->fl6_dport;
907 uh->len = htons(up->len);
908 uh->check = 0;
909
910 if (is_udplite)
911 csum = udplite_csum_outgoing(sk, skb);
912 else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */
913 udp6_hwcsum_outgoing(sk, skb, &fl6->saddr, &fl6->daddr,
914 up->len);
915 goto send;
916 } else
917 csum = udp_csum_outgoing(sk, skb);
918
919 /* add protocol-dependent pseudo-header */
920 uh->check = csum_ipv6_magic(&fl6->saddr, &fl6->daddr,
921 up->len, fl6->flowi6_proto, csum);
922 if (uh->check == 0)
923 uh->check = CSUM_MANGLED_0;
924
925 send:
926 err = ip6_push_pending_frames(sk);
927 if (err) {
928 if (err == -ENOBUFS && !inet6_sk(sk)->recverr) {
929 UDP6_INC_STATS_USER(sock_net(sk),
930 UDP_MIB_SNDBUFERRORS, is_udplite);
931 err = 0;
932 }
933 } else
934 UDP6_INC_STATS_USER(sock_net(sk),
935 UDP_MIB_OUTDATAGRAMS, is_udplite);
936 out:
937 up->len = 0;
938 up->pending = 0;
939 return err;
940 }
941
udpv6_sendmsg(struct kiocb * iocb,struct sock * sk,struct msghdr * msg,size_t len)942 int udpv6_sendmsg(struct kiocb *iocb, struct sock *sk,
943 struct msghdr *msg, size_t len)
944 {
945 struct ipv6_txoptions opt_space;
946 struct udp_sock *up = udp_sk(sk);
947 struct inet_sock *inet = inet_sk(sk);
948 struct ipv6_pinfo *np = inet6_sk(sk);
949 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) msg->msg_name;
950 struct in6_addr *daddr, *final_p, final;
951 struct ipv6_txoptions *opt = NULL;
952 struct ip6_flowlabel *flowlabel = NULL;
953 struct flowi6 fl6;
954 struct dst_entry *dst;
955 int addr_len = msg->msg_namelen;
956 int ulen = len;
957 int hlimit = -1;
958 int tclass = -1;
959 int dontfrag = -1;
960 int corkreq = up->corkflag || msg->msg_flags&MSG_MORE;
961 int err;
962 int connected = 0;
963 int is_udplite = IS_UDPLITE(sk);
964 int (*getfrag)(void *, char *, int, int, int, struct sk_buff *);
965
966 /* destination address check */
967 if (sin6) {
968 if (addr_len < offsetof(struct sockaddr, sa_data))
969 return -EINVAL;
970
971 switch (sin6->sin6_family) {
972 case AF_INET6:
973 if (addr_len < SIN6_LEN_RFC2133)
974 return -EINVAL;
975 daddr = &sin6->sin6_addr;
976 break;
977 case AF_INET:
978 goto do_udp_sendmsg;
979 case AF_UNSPEC:
980 msg->msg_name = sin6 = NULL;
981 msg->msg_namelen = addr_len = 0;
982 daddr = NULL;
983 break;
984 default:
985 return -EINVAL;
986 }
987 } else if (!up->pending) {
988 if (sk->sk_state != TCP_ESTABLISHED)
989 return -EDESTADDRREQ;
990 daddr = &np->daddr;
991 } else
992 daddr = NULL;
993
994 if (daddr) {
995 if (ipv6_addr_v4mapped(daddr)) {
996 struct sockaddr_in sin;
997 sin.sin_family = AF_INET;
998 sin.sin_port = sin6 ? sin6->sin6_port : inet->inet_dport;
999 sin.sin_addr.s_addr = daddr->s6_addr32[3];
1000 msg->msg_name = &sin;
1001 msg->msg_namelen = sizeof(sin);
1002 do_udp_sendmsg:
1003 if (__ipv6_only_sock(sk))
1004 return -ENETUNREACH;
1005 return udp_sendmsg(iocb, sk, msg, len);
1006 }
1007 }
1008
1009 if (up->pending == AF_INET)
1010 return udp_sendmsg(iocb, sk, msg, len);
1011
1012 /* Rough check on arithmetic overflow,
1013 better check is made in ip6_append_data().
1014 */
1015 if (len > INT_MAX - sizeof(struct udphdr))
1016 return -EMSGSIZE;
1017
1018 if (up->pending) {
1019 /*
1020 * There are pending frames.
1021 * The socket lock must be held while it's corked.
1022 */
1023 lock_sock(sk);
1024 if (likely(up->pending)) {
1025 if (unlikely(up->pending != AF_INET6)) {
1026 release_sock(sk);
1027 return -EAFNOSUPPORT;
1028 }
1029 dst = NULL;
1030 goto do_append_data;
1031 }
1032 release_sock(sk);
1033 }
1034 ulen += sizeof(struct udphdr);
1035
1036 memset(&fl6, 0, sizeof(fl6));
1037
1038 if (sin6) {
1039 if (sin6->sin6_port == 0)
1040 return -EINVAL;
1041
1042 fl6.fl6_dport = sin6->sin6_port;
1043 daddr = &sin6->sin6_addr;
1044
1045 if (np->sndflow) {
1046 fl6.flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK;
1047 if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) {
1048 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1049 if (flowlabel == NULL)
1050 return -EINVAL;
1051 daddr = &flowlabel->dst;
1052 }
1053 }
1054
1055 /*
1056 * Otherwise it will be difficult to maintain
1057 * sk->sk_dst_cache.
1058 */
1059 if (sk->sk_state == TCP_ESTABLISHED &&
1060 ipv6_addr_equal(daddr, &np->daddr))
1061 daddr = &np->daddr;
1062
1063 if (addr_len >= sizeof(struct sockaddr_in6) &&
1064 sin6->sin6_scope_id &&
1065 ipv6_addr_type(daddr)&IPV6_ADDR_LINKLOCAL)
1066 fl6.flowi6_oif = sin6->sin6_scope_id;
1067 } else {
1068 if (sk->sk_state != TCP_ESTABLISHED)
1069 return -EDESTADDRREQ;
1070
1071 fl6.fl6_dport = inet->inet_dport;
1072 daddr = &np->daddr;
1073 fl6.flowlabel = np->flow_label;
1074 connected = 1;
1075 }
1076
1077 if (!fl6.flowi6_oif)
1078 fl6.flowi6_oif = sk->sk_bound_dev_if;
1079
1080 if (!fl6.flowi6_oif)
1081 fl6.flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;
1082
1083 fl6.flowi6_mark = sk->sk_mark;
1084
1085 if (msg->msg_controllen) {
1086 opt = &opt_space;
1087 memset(opt, 0, sizeof(struct ipv6_txoptions));
1088 opt->tot_len = sizeof(*opt);
1089
1090 err = datagram_send_ctl(sock_net(sk), msg, &fl6, opt, &hlimit,
1091 &tclass, &dontfrag);
1092 if (err < 0) {
1093 fl6_sock_release(flowlabel);
1094 return err;
1095 }
1096 if ((fl6.flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) {
1097 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
1098 if (flowlabel == NULL)
1099 return -EINVAL;
1100 }
1101 if (!(opt->opt_nflen|opt->opt_flen))
1102 opt = NULL;
1103 connected = 0;
1104 }
1105 if (opt == NULL)
1106 opt = np->opt;
1107 if (flowlabel)
1108 opt = fl6_merge_options(&opt_space, flowlabel, opt);
1109 opt = ipv6_fixup_options(&opt_space, opt);
1110
1111 fl6.flowi6_proto = sk->sk_protocol;
1112 if (!ipv6_addr_any(daddr))
1113 ipv6_addr_copy(&fl6.daddr, daddr);
1114 else
1115 fl6.daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */
1116 if (ipv6_addr_any(&fl6.saddr) && !ipv6_addr_any(&np->saddr))
1117 ipv6_addr_copy(&fl6.saddr, &np->saddr);
1118 fl6.fl6_sport = inet->inet_sport;
1119
1120 final_p = fl6_update_dst(&fl6, opt, &final);
1121 if (final_p)
1122 connected = 0;
1123
1124 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr)) {
1125 fl6.flowi6_oif = np->mcast_oif;
1126 connected = 0;
1127 }
1128
1129 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
1130
1131 dst = ip6_sk_dst_lookup_flow(sk, &fl6, final_p, true);
1132 if (IS_ERR(dst)) {
1133 err = PTR_ERR(dst);
1134 dst = NULL;
1135 goto out;
1136 }
1137
1138 if (hlimit < 0) {
1139 if (ipv6_addr_is_multicast(&fl6.daddr))
1140 hlimit = np->mcast_hops;
1141 else
1142 hlimit = np->hop_limit;
1143 if (hlimit < 0)
1144 hlimit = ip6_dst_hoplimit(dst);
1145 }
1146
1147 if (tclass < 0)
1148 tclass = np->tclass;
1149
1150 if (dontfrag < 0)
1151 dontfrag = np->dontfrag;
1152
1153 if (msg->msg_flags&MSG_CONFIRM)
1154 goto do_confirm;
1155 back_from_confirm:
1156
1157 lock_sock(sk);
1158 if (unlikely(up->pending)) {
1159 /* The socket is already corked while preparing it. */
1160 /* ... which is an evident application bug. --ANK */
1161 release_sock(sk);
1162
1163 LIMIT_NETDEBUG(KERN_DEBUG "udp cork app bug 2\n");
1164 err = -EINVAL;
1165 goto out;
1166 }
1167
1168 up->pending = AF_INET6;
1169
1170 do_append_data:
1171 up->len += ulen;
1172 getfrag = is_udplite ? udplite_getfrag : ip_generic_getfrag;
1173 err = ip6_append_data(sk, getfrag, msg->msg_iov, ulen,
1174 sizeof(struct udphdr), hlimit, tclass, opt, &fl6,
1175 (struct rt6_info*)dst,
1176 corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags, dontfrag);
1177 if (err)
1178 udp_v6_flush_pending_frames(sk);
1179 else if (!corkreq)
1180 err = udp_v6_push_pending_frames(sk);
1181 else if (unlikely(skb_queue_empty(&sk->sk_write_queue)))
1182 up->pending = 0;
1183
1184 if (dst) {
1185 if (connected) {
1186 ip6_dst_store(sk, dst,
1187 ipv6_addr_equal(&fl6.daddr, &np->daddr) ?
1188 &np->daddr : NULL,
1189 #ifdef CONFIG_IPV6_SUBTREES
1190 ipv6_addr_equal(&fl6.saddr, &np->saddr) ?
1191 &np->saddr :
1192 #endif
1193 NULL);
1194 } else {
1195 dst_release(dst);
1196 }
1197 dst = NULL;
1198 }
1199
1200 if (err > 0)
1201 err = np->recverr ? net_xmit_errno(err) : 0;
1202 release_sock(sk);
1203 out:
1204 dst_release(dst);
1205 fl6_sock_release(flowlabel);
1206 if (!err)
1207 return len;
1208 /*
1209 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space. Reporting
1210 * ENOBUFS might not be good (it's not tunable per se), but otherwise
1211 * we don't have a good statistic (IpOutDiscards but it can be too many
1212 * things). We could add another new stat but at least for now that
1213 * seems like overkill.
1214 */
1215 if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) {
1216 UDP6_INC_STATS_USER(sock_net(sk),
1217 UDP_MIB_SNDBUFERRORS, is_udplite);
1218 }
1219 return err;
1220
1221 do_confirm:
1222 dst_confirm(dst);
1223 if (!(msg->msg_flags&MSG_PROBE) || len)
1224 goto back_from_confirm;
1225 err = 0;
1226 goto out;
1227 }
1228
udpv6_destroy_sock(struct sock * sk)1229 void udpv6_destroy_sock(struct sock *sk)
1230 {
1231 lock_sock(sk);
1232 udp_v6_flush_pending_frames(sk);
1233 release_sock(sk);
1234
1235 inet6_destroy_sock(sk);
1236 }
1237
1238 /*
1239 * Socket option code for UDP
1240 */
udpv6_setsockopt(struct sock * sk,int level,int optname,char __user * optval,unsigned int optlen)1241 int udpv6_setsockopt(struct sock *sk, int level, int optname,
1242 char __user *optval, unsigned int optlen)
1243 {
1244 if (level == SOL_UDP || level == SOL_UDPLITE)
1245 return udp_lib_setsockopt(sk, level, optname, optval, optlen,
1246 udp_v6_push_pending_frames);
1247 return ipv6_setsockopt(sk, level, optname, optval, optlen);
1248 }
1249
1250 #ifdef CONFIG_COMPAT
compat_udpv6_setsockopt(struct sock * sk,int level,int optname,char __user * optval,unsigned int optlen)1251 int compat_udpv6_setsockopt(struct sock *sk, int level, int optname,
1252 char __user *optval, unsigned int optlen)
1253 {
1254 if (level == SOL_UDP || level == SOL_UDPLITE)
1255 return udp_lib_setsockopt(sk, level, optname, optval, optlen,
1256 udp_v6_push_pending_frames);
1257 return compat_ipv6_setsockopt(sk, level, optname, optval, optlen);
1258 }
1259 #endif
1260
udpv6_getsockopt(struct sock * sk,int level,int optname,char __user * optval,int __user * optlen)1261 int udpv6_getsockopt(struct sock *sk, int level, int optname,
1262 char __user *optval, int __user *optlen)
1263 {
1264 if (level == SOL_UDP || level == SOL_UDPLITE)
1265 return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1266 return ipv6_getsockopt(sk, level, optname, optval, optlen);
1267 }
1268
1269 #ifdef CONFIG_COMPAT
compat_udpv6_getsockopt(struct sock * sk,int level,int optname,char __user * optval,int __user * optlen)1270 int compat_udpv6_getsockopt(struct sock *sk, int level, int optname,
1271 char __user *optval, int __user *optlen)
1272 {
1273 if (level == SOL_UDP || level == SOL_UDPLITE)
1274 return udp_lib_getsockopt(sk, level, optname, optval, optlen);
1275 return compat_ipv6_getsockopt(sk, level, optname, optval, optlen);
1276 }
1277 #endif
1278
udp6_ufo_send_check(struct sk_buff * skb)1279 static int udp6_ufo_send_check(struct sk_buff *skb)
1280 {
1281 struct ipv6hdr *ipv6h;
1282 struct udphdr *uh;
1283
1284 if (!pskb_may_pull(skb, sizeof(*uh)))
1285 return -EINVAL;
1286
1287 ipv6h = ipv6_hdr(skb);
1288 uh = udp_hdr(skb);
1289
1290 uh->check = ~csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr, skb->len,
1291 IPPROTO_UDP, 0);
1292 skb->csum_start = skb_transport_header(skb) - skb->head;
1293 skb->csum_offset = offsetof(struct udphdr, check);
1294 skb->ip_summed = CHECKSUM_PARTIAL;
1295 return 0;
1296 }
1297
udp6_ufo_fragment(struct sk_buff * skb,u32 features)1298 static struct sk_buff *udp6_ufo_fragment(struct sk_buff *skb, u32 features)
1299 {
1300 struct sk_buff *segs = ERR_PTR(-EINVAL);
1301 unsigned int mss;
1302 unsigned int unfrag_ip6hlen, unfrag_len;
1303 struct frag_hdr *fptr;
1304 u8 *mac_start, *prevhdr;
1305 u8 nexthdr;
1306 u8 frag_hdr_sz = sizeof(struct frag_hdr);
1307 int offset;
1308 __wsum csum;
1309
1310 mss = skb_shinfo(skb)->gso_size;
1311 if (unlikely(skb->len <= mss))
1312 goto out;
1313
1314 if (skb_gso_ok(skb, features | NETIF_F_GSO_ROBUST)) {
1315 /* Packet is from an untrusted source, reset gso_segs. */
1316 int type = skb_shinfo(skb)->gso_type;
1317
1318 if (unlikely(type & ~(SKB_GSO_UDP | SKB_GSO_DODGY) ||
1319 !(type & (SKB_GSO_UDP))))
1320 goto out;
1321
1322 skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(skb->len, mss);
1323
1324 segs = NULL;
1325 goto out;
1326 }
1327
1328 /* Do software UFO. Complete and fill in the UDP checksum as HW cannot
1329 * do checksum of UDP packets sent as multiple IP fragments.
1330 */
1331 offset = skb->csum_start - skb_headroom(skb);
1332 csum = skb_checksum(skb, offset, skb->len- offset, 0);
1333 offset += skb->csum_offset;
1334 *(__sum16 *)(skb->data + offset) = csum_fold(csum);
1335 skb->ip_summed = CHECKSUM_NONE;
1336
1337 /* Check if there is enough headroom to insert fragment header. */
1338 if ((skb_mac_header(skb) < skb->head + frag_hdr_sz) &&
1339 pskb_expand_head(skb, frag_hdr_sz, 0, GFP_ATOMIC))
1340 goto out;
1341
1342 /* Find the unfragmentable header and shift it left by frag_hdr_sz
1343 * bytes to insert fragment header.
1344 */
1345 unfrag_ip6hlen = ip6_find_1stfragopt(skb, &prevhdr);
1346 nexthdr = *prevhdr;
1347 *prevhdr = NEXTHDR_FRAGMENT;
1348 unfrag_len = skb_network_header(skb) - skb_mac_header(skb) +
1349 unfrag_ip6hlen;
1350 mac_start = skb_mac_header(skb);
1351 memmove(mac_start-frag_hdr_sz, mac_start, unfrag_len);
1352
1353 skb->mac_header -= frag_hdr_sz;
1354 skb->network_header -= frag_hdr_sz;
1355
1356 fptr = (struct frag_hdr *)(skb_network_header(skb) + unfrag_ip6hlen);
1357 fptr->nexthdr = nexthdr;
1358 fptr->reserved = 0;
1359 ipv6_select_ident(fptr);
1360
1361 /* Fragment the skb. ipv6 header and the remaining fields of the
1362 * fragment header are updated in ipv6_gso_segment()
1363 */
1364 segs = skb_segment(skb, features);
1365
1366 out:
1367 return segs;
1368 }
1369
1370 static const struct inet6_protocol udpv6_protocol = {
1371 .handler = udpv6_rcv,
1372 .err_handler = udpv6_err,
1373 .gso_send_check = udp6_ufo_send_check,
1374 .gso_segment = udp6_ufo_fragment,
1375 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1376 };
1377
1378 /* ------------------------------------------------------------------------ */
1379 #ifdef CONFIG_PROC_FS
1380
udp6_sock_seq_show(struct seq_file * seq,struct sock * sp,int bucket)1381 static void udp6_sock_seq_show(struct seq_file *seq, struct sock *sp, int bucket)
1382 {
1383 struct inet_sock *inet = inet_sk(sp);
1384 struct ipv6_pinfo *np = inet6_sk(sp);
1385 struct in6_addr *dest, *src;
1386 __u16 destp, srcp;
1387
1388 dest = &np->daddr;
1389 src = &np->rcv_saddr;
1390 destp = ntohs(inet->inet_dport);
1391 srcp = ntohs(inet->inet_sport);
1392 seq_printf(seq,
1393 "%5d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1394 "%02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %p %d\n",
1395 bucket,
1396 src->s6_addr32[0], src->s6_addr32[1],
1397 src->s6_addr32[2], src->s6_addr32[3], srcp,
1398 dest->s6_addr32[0], dest->s6_addr32[1],
1399 dest->s6_addr32[2], dest->s6_addr32[3], destp,
1400 sp->sk_state,
1401 sk_wmem_alloc_get(sp),
1402 sk_rmem_alloc_get(sp),
1403 0, 0L, 0,
1404 sock_i_uid(sp), 0,
1405 sock_i_ino(sp),
1406 atomic_read(&sp->sk_refcnt), sp,
1407 atomic_read(&sp->sk_drops));
1408 }
1409
udp6_seq_show(struct seq_file * seq,void * v)1410 int udp6_seq_show(struct seq_file *seq, void *v)
1411 {
1412 if (v == SEQ_START_TOKEN)
1413 seq_printf(seq,
1414 " sl "
1415 "local_address "
1416 "remote_address "
1417 "st tx_queue rx_queue tr tm->when retrnsmt"
1418 " uid timeout inode ref pointer drops\n");
1419 else
1420 udp6_sock_seq_show(seq, v, ((struct udp_iter_state *)seq->private)->bucket);
1421 return 0;
1422 }
1423
1424 static struct udp_seq_afinfo udp6_seq_afinfo = {
1425 .name = "udp6",
1426 .family = AF_INET6,
1427 .udp_table = &udp_table,
1428 .seq_fops = {
1429 .owner = THIS_MODULE,
1430 },
1431 .seq_ops = {
1432 .show = udp6_seq_show,
1433 },
1434 };
1435
udp6_proc_init(struct net * net)1436 int __net_init udp6_proc_init(struct net *net)
1437 {
1438 return udp_proc_register(net, &udp6_seq_afinfo);
1439 }
1440
udp6_proc_exit(struct net * net)1441 void udp6_proc_exit(struct net *net) {
1442 udp_proc_unregister(net, &udp6_seq_afinfo);
1443 }
1444 #endif /* CONFIG_PROC_FS */
1445
1446 /* ------------------------------------------------------------------------ */
1447
1448 struct proto udpv6_prot = {
1449 .name = "UDPv6",
1450 .owner = THIS_MODULE,
1451 .close = udp_lib_close,
1452 .connect = ip6_datagram_connect,
1453 .disconnect = udp_disconnect,
1454 .ioctl = udp_ioctl,
1455 .destroy = udpv6_destroy_sock,
1456 .setsockopt = udpv6_setsockopt,
1457 .getsockopt = udpv6_getsockopt,
1458 .sendmsg = udpv6_sendmsg,
1459 .recvmsg = udpv6_recvmsg,
1460 .backlog_rcv = udpv6_queue_rcv_skb,
1461 .hash = udp_lib_hash,
1462 .unhash = udp_lib_unhash,
1463 .rehash = udp_v6_rehash,
1464 .get_port = udp_v6_get_port,
1465 .memory_allocated = &udp_memory_allocated,
1466 .sysctl_mem = sysctl_udp_mem,
1467 .sysctl_wmem = &sysctl_udp_wmem_min,
1468 .sysctl_rmem = &sysctl_udp_rmem_min,
1469 .obj_size = sizeof(struct udp6_sock),
1470 .slab_flags = SLAB_DESTROY_BY_RCU,
1471 .h.udp_table = &udp_table,
1472 #ifdef CONFIG_COMPAT
1473 .compat_setsockopt = compat_udpv6_setsockopt,
1474 .compat_getsockopt = compat_udpv6_getsockopt,
1475 #endif
1476 .clear_sk = sk_prot_clear_portaddr_nulls,
1477 };
1478
1479 static struct inet_protosw udpv6_protosw = {
1480 .type = SOCK_DGRAM,
1481 .protocol = IPPROTO_UDP,
1482 .prot = &udpv6_prot,
1483 .ops = &inet6_dgram_ops,
1484 .no_check = UDP_CSUM_DEFAULT,
1485 .flags = INET_PROTOSW_PERMANENT,
1486 };
1487
1488
udpv6_init(void)1489 int __init udpv6_init(void)
1490 {
1491 int ret;
1492
1493 ret = inet6_add_protocol(&udpv6_protocol, IPPROTO_UDP);
1494 if (ret)
1495 goto out;
1496
1497 ret = inet6_register_protosw(&udpv6_protosw);
1498 if (ret)
1499 goto out_udpv6_protocol;
1500 out:
1501 return ret;
1502
1503 out_udpv6_protocol:
1504 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1505 goto out;
1506 }
1507
udpv6_exit(void)1508 void udpv6_exit(void)
1509 {
1510 inet6_unregister_protosw(&udpv6_protosw);
1511 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
1512 }
1513