1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * RAW sockets for IPv6
4 * Linux INET6 implementation
5 *
6 * Authors:
7 * Pedro Roque <roque@di.fc.ul.pt>
8 *
9 * Adapted from linux/net/ipv4/raw.c
10 *
11 * Fixes:
12 * Hideaki YOSHIFUJI : sin6_scope_id support
13 * YOSHIFUJI,H.@USAGI : raw checksum (RFC2292(bis) compliance)
14 * Kazunori MIYAZAWA @USAGI: change process style to use ip6_append_data
15 */
16
17 #include <linux/errno.h>
18 #include <linux/types.h>
19 #include <linux/socket.h>
20 #include <linux/slab.h>
21 #include <linux/sockios.h>
22 #include <linux/net.h>
23 #include <linux/in6.h>
24 #include <linux/netdevice.h>
25 #include <linux/if_arp.h>
26 #include <linux/icmpv6.h>
27 #include <linux/netfilter.h>
28 #include <linux/netfilter_ipv6.h>
29 #include <linux/skbuff.h>
30 #include <linux/compat.h>
31 #include <linux/uaccess.h>
32 #include <asm/ioctls.h>
33
34 #include <net/net_namespace.h>
35 #include <net/ip.h>
36 #include <net/sock.h>
37 #include <net/snmp.h>
38
39 #include <net/ipv6.h>
40 #include <net/ndisc.h>
41 #include <net/protocol.h>
42 #include <net/ip6_route.h>
43 #include <net/ip6_checksum.h>
44 #include <net/addrconf.h>
45 #include <net/transp_v6.h>
46 #include <net/udp.h>
47 #include <net/inet_common.h>
48 #include <net/tcp_states.h>
49 #if IS_ENABLED(CONFIG_IPV6_MIP6)
50 #include <net/mip6.h>
51 #endif
52 #include <linux/mroute6.h>
53
54 #include <net/raw.h>
55 #include <net/rawv6.h>
56 #include <net/xfrm.h>
57
58 #include <linux/proc_fs.h>
59 #include <linux/seq_file.h>
60 #include <linux/export.h>
61
62 #define ICMPV6_HDRLEN 4 /* ICMPv6 header, RFC 4443 Section 2.1 */
63
64 struct raw_hashinfo raw_v6_hashinfo;
65 EXPORT_SYMBOL_GPL(raw_v6_hashinfo);
66
raw_v6_match(struct net * net,const struct sock * sk,unsigned short num,const struct in6_addr * loc_addr,const struct in6_addr * rmt_addr,int dif,int sdif)67 bool raw_v6_match(struct net *net, const struct sock *sk, unsigned short num,
68 const struct in6_addr *loc_addr,
69 const struct in6_addr *rmt_addr, int dif, int sdif)
70 {
71 if (inet_sk(sk)->inet_num != num ||
72 !net_eq(sock_net(sk), net) ||
73 (!ipv6_addr_any(&sk->sk_v6_daddr) &&
74 !ipv6_addr_equal(&sk->sk_v6_daddr, rmt_addr)) ||
75 !raw_sk_bound_dev_eq(net, sk->sk_bound_dev_if,
76 dif, sdif))
77 return false;
78
79 if (ipv6_addr_any(&sk->sk_v6_rcv_saddr) ||
80 ipv6_addr_equal(&sk->sk_v6_rcv_saddr, loc_addr) ||
81 (ipv6_addr_is_multicast(loc_addr) &&
82 inet6_mc_check(sk, loc_addr, rmt_addr)))
83 return true;
84
85 return false;
86 }
87 EXPORT_SYMBOL_GPL(raw_v6_match);
88
89 /*
90 * 0 - deliver
91 * 1 - block
92 */
icmpv6_filter(const struct sock * sk,struct sk_buff * skb)93 static int icmpv6_filter(const struct sock *sk, struct sk_buff *skb)
94 {
95 const struct icmp6hdr *hdr;
96 const __u32 *data;
97 unsigned int type;
98
99 /* We require only the four bytes of the ICMPv6 header, not any
100 * additional bytes of message body in "struct icmp6hdr".
101 */
102 if (!pskb_may_pull(skb, ICMPV6_HDRLEN))
103 return 1;
104
105 hdr = (struct icmp6hdr *)skb->data;
106 type = hdr->icmp6_type;
107
108 data = &raw6_sk(sk)->filter.data[0];
109
110 return (data[type >> 5] & (1U << (type & 31))) != 0;
111 }
112
113 #if IS_ENABLED(CONFIG_IPV6_MIP6)
114 typedef int mh_filter_t(struct sock *sock, struct sk_buff *skb);
115
116 static mh_filter_t __rcu *mh_filter __read_mostly;
117
rawv6_mh_filter_register(mh_filter_t filter)118 int rawv6_mh_filter_register(mh_filter_t filter)
119 {
120 rcu_assign_pointer(mh_filter, filter);
121 return 0;
122 }
123 EXPORT_SYMBOL(rawv6_mh_filter_register);
124
rawv6_mh_filter_unregister(mh_filter_t filter)125 int rawv6_mh_filter_unregister(mh_filter_t filter)
126 {
127 RCU_INIT_POINTER(mh_filter, NULL);
128 synchronize_rcu();
129 return 0;
130 }
131 EXPORT_SYMBOL(rawv6_mh_filter_unregister);
132
133 #endif
134
135 /*
136 * demultiplex raw sockets.
137 * (should consider queueing the skb in the sock receive_queue
138 * without calling rawv6.c)
139 *
140 * Caller owns SKB so we must make clones.
141 */
ipv6_raw_deliver(struct sk_buff * skb,int nexthdr)142 static bool ipv6_raw_deliver(struct sk_buff *skb, int nexthdr)
143 {
144 struct net *net = dev_net(skb->dev);
145 const struct ipv6hdr *ip6h;
146 struct hlist_head *hlist;
147 bool delivered = false;
148 struct sock *sk;
149 __u8 hash;
150
151 ip6h = ipv6_hdr(skb);
152
153 hash = raw_hashfunc(net, nexthdr);
154 hlist = &raw_v6_hashinfo.ht[hash];
155 rcu_read_lock();
156 sk_for_each_rcu(sk, hlist) {
157 int filtered;
158
159 if (!raw_v6_match(net, sk, nexthdr, &ip6h->daddr, &ip6h->saddr,
160 inet6_iif(skb), inet6_sdif(skb)))
161 continue;
162
163 if (atomic_read(&sk->sk_rmem_alloc) >=
164 READ_ONCE(sk->sk_rcvbuf)) {
165 sk_drops_inc(sk);
166 continue;
167 }
168
169 delivered = true;
170 switch (nexthdr) {
171 case IPPROTO_ICMPV6:
172 filtered = icmpv6_filter(sk, skb);
173 ip6h = ipv6_hdr(skb);
174 break;
175
176 #if IS_ENABLED(CONFIG_IPV6_MIP6)
177 case IPPROTO_MH:
178 {
179 /* XXX: To validate MH only once for each packet,
180 * this is placed here. It should be after checking
181 * xfrm policy, however it doesn't. The checking xfrm
182 * policy is placed in rawv6_rcv() because it is
183 * required for each socket.
184 */
185 mh_filter_t *filter;
186
187 filter = rcu_dereference(mh_filter);
188 filtered = filter ? (*filter)(sk, skb) : 0;
189 break;
190 }
191 #endif
192 default:
193 filtered = 0;
194 break;
195 }
196
197 if (filtered < 0)
198 break;
199 if (filtered == 0) {
200 struct sk_buff *clone = skb_clone(skb, GFP_ATOMIC);
201
202 /* Not releasing hash table! */
203 if (clone)
204 rawv6_rcv(sk, clone);
205 }
206 }
207 rcu_read_unlock();
208 return delivered;
209 }
210
raw6_local_deliver(struct sk_buff * skb,int nexthdr)211 bool raw6_local_deliver(struct sk_buff *skb, int nexthdr)
212 {
213 return ipv6_raw_deliver(skb, nexthdr);
214 }
215
216 /* This cleans up af_inet6 a bit. -DaveM */
rawv6_bind(struct sock * sk,struct sockaddr_unsized * uaddr,int addr_len)217 static int rawv6_bind(struct sock *sk, struct sockaddr_unsized *uaddr,
218 int addr_len)
219 {
220 struct inet_sock *inet = inet_sk(sk);
221 struct ipv6_pinfo *np = inet6_sk(sk);
222 struct sockaddr_in6 *addr = (struct sockaddr_in6 *) uaddr;
223 __be32 v4addr = 0;
224 int addr_type;
225 int err;
226
227 if (addr_len < SIN6_LEN_RFC2133)
228 return -EINVAL;
229
230 if (addr->sin6_family != AF_INET6)
231 return -EINVAL;
232
233 addr_type = ipv6_addr_type(&addr->sin6_addr);
234
235 /* Raw sockets are IPv6 only */
236 if (addr_type == IPV6_ADDR_MAPPED)
237 return -EADDRNOTAVAIL;
238
239 lock_sock(sk);
240
241 err = -EINVAL;
242 if (sk->sk_state != TCP_CLOSE)
243 goto out;
244
245 rcu_read_lock();
246 /* Check if the address belongs to the host. */
247 if (addr_type != IPV6_ADDR_ANY) {
248 struct net_device *dev = NULL;
249
250 if (__ipv6_addr_needs_scope_id(addr_type)) {
251 if (addr_len >= sizeof(struct sockaddr_in6) &&
252 addr->sin6_scope_id) {
253 /* Override any existing binding, if another
254 * one is supplied by user.
255 */
256 sk->sk_bound_dev_if = addr->sin6_scope_id;
257 }
258
259 /* Binding to link-local address requires an interface */
260 if (!sk->sk_bound_dev_if)
261 goto out_unlock;
262 }
263
264 if (sk->sk_bound_dev_if) {
265 err = -ENODEV;
266 dev = dev_get_by_index_rcu(sock_net(sk),
267 sk->sk_bound_dev_if);
268 if (!dev)
269 goto out_unlock;
270 }
271
272 /* ipv4 addr of the socket is invalid. Only the
273 * unspecified and mapped address have a v4 equivalent.
274 */
275 v4addr = LOOPBACK4_IPV6;
276 if (!(addr_type & IPV6_ADDR_MULTICAST) &&
277 !ipv6_can_nonlocal_bind(sock_net(sk), inet)) {
278 err = -EADDRNOTAVAIL;
279 if (!ipv6_chk_addr(sock_net(sk), &addr->sin6_addr,
280 dev, 0)) {
281 goto out_unlock;
282 }
283 }
284 }
285
286 inet->inet_rcv_saddr = inet->inet_saddr = v4addr;
287 sk->sk_v6_rcv_saddr = addr->sin6_addr;
288 if (!(addr_type & IPV6_ADDR_MULTICAST))
289 np->saddr = addr->sin6_addr;
290 err = 0;
291 out_unlock:
292 rcu_read_unlock();
293 out:
294 release_sock(sk);
295 return err;
296 }
297
rawv6_err(struct sock * sk,struct sk_buff * skb,u8 type,u8 code,int offset,__be32 info)298 static void rawv6_err(struct sock *sk, struct sk_buff *skb,
299 u8 type, u8 code, int offset, __be32 info)
300 {
301 bool recverr = inet6_test_bit(RECVERR6, sk);
302 struct ipv6_pinfo *np = inet6_sk(sk);
303 int err;
304 int harderr;
305
306 /* Report error on raw socket, if:
307 1. User requested recverr.
308 2. Socket is connected (otherwise the error indication
309 is useless without recverr and error is hard.
310 */
311 if (!recverr && sk->sk_state != TCP_ESTABLISHED)
312 return;
313
314 harderr = icmpv6_err_convert(type, code, &err);
315 if (type == ICMPV6_PKT_TOOBIG) {
316 ip6_sk_update_pmtu(skb, sk, info);
317 harderr = (READ_ONCE(np->pmtudisc) == IPV6_PMTUDISC_DO);
318 }
319 if (type == NDISC_REDIRECT) {
320 ip6_sk_redirect(skb, sk);
321 return;
322 }
323 if (recverr) {
324 u8 *payload = skb->data;
325 if (!inet_test_bit(HDRINCL, sk))
326 payload += offset;
327 ipv6_icmp_error(sk, skb, err, 0, ntohl(info), payload);
328 }
329
330 if (recverr || harderr) {
331 sk->sk_err = err;
332 sk_error_report(sk);
333 }
334 }
335
raw6_icmp_error(struct sk_buff * skb,int nexthdr,u8 type,u8 code,int inner_offset,__be32 info)336 void raw6_icmp_error(struct sk_buff *skb, int nexthdr,
337 u8 type, u8 code, int inner_offset, __be32 info)
338 {
339 struct net *net = dev_net(skb->dev);
340 struct hlist_head *hlist;
341 struct sock *sk;
342 int hash;
343
344 hash = raw_hashfunc(net, nexthdr);
345 hlist = &raw_v6_hashinfo.ht[hash];
346 rcu_read_lock();
347 sk_for_each_rcu(sk, hlist) {
348 /* Note: ipv6_hdr(skb) != skb->data */
349 const struct ipv6hdr *ip6h = (const struct ipv6hdr *)skb->data;
350
351 if (!raw_v6_match(net, sk, nexthdr, &ip6h->saddr, &ip6h->daddr,
352 inet6_iif(skb), inet6_iif(skb)))
353 continue;
354 rawv6_err(sk, skb, type, code, inner_offset, info);
355 }
356 rcu_read_unlock();
357 }
358
rawv6_rcv_skb(struct sock * sk,struct sk_buff * skb)359 static inline int rawv6_rcv_skb(struct sock *sk, struct sk_buff *skb)
360 {
361 enum skb_drop_reason reason;
362
363 if ((raw6_sk(sk)->checksum || rcu_access_pointer(sk->sk_filter)) &&
364 skb_checksum_complete(skb)) {
365 sk_drops_inc(sk);
366 sk_skb_reason_drop(sk, skb, SKB_DROP_REASON_SKB_CSUM);
367 return NET_RX_DROP;
368 }
369
370 /* Charge it to the socket. */
371 skb_dst_drop(skb);
372 if (sock_queue_rcv_skb_reason(sk, skb, &reason) < 0) {
373 sk_skb_reason_drop(sk, skb, reason);
374 return NET_RX_DROP;
375 }
376
377 return 0;
378 }
379
380 /*
381 * This is next to useless...
382 * if we demultiplex in network layer we don't need the extra call
383 * just to queue the skb...
384 * maybe we could have the network decide upon a hint if it
385 * should call raw_rcv for demultiplexing
386 */
rawv6_rcv(struct sock * sk,struct sk_buff * skb)387 int rawv6_rcv(struct sock *sk, struct sk_buff *skb)
388 {
389 struct inet_sock *inet = inet_sk(sk);
390 struct raw6_sock *rp = raw6_sk(sk);
391
392 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) {
393 sk_drops_inc(sk);
394 sk_skb_reason_drop(sk, skb, SKB_DROP_REASON_XFRM_POLICY);
395 return NET_RX_DROP;
396 }
397 nf_reset_ct(skb);
398
399 if (!rp->checksum)
400 skb->ip_summed = CHECKSUM_UNNECESSARY;
401
402 if (skb->ip_summed == CHECKSUM_COMPLETE) {
403 skb_postpull_rcsum(skb, skb_network_header(skb),
404 skb_network_header_len(skb));
405 if (!csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
406 &ipv6_hdr(skb)->daddr,
407 skb->len, inet->inet_num, skb->csum))
408 skb->ip_summed = CHECKSUM_UNNECESSARY;
409 }
410 if (!skb_csum_unnecessary(skb))
411 skb->csum = ~csum_unfold(csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
412 &ipv6_hdr(skb)->daddr,
413 skb->len,
414 inet->inet_num, 0));
415
416 if (inet_test_bit(HDRINCL, sk)) {
417 if (skb_checksum_complete(skb)) {
418 sk_drops_inc(sk);
419 sk_skb_reason_drop(sk, skb, SKB_DROP_REASON_SKB_CSUM);
420 return NET_RX_DROP;
421 }
422 }
423
424 rawv6_rcv_skb(sk, skb);
425 return 0;
426 }
427
428
429 /*
430 * This should be easy, if there is something there
431 * we return it, otherwise we block.
432 */
433
rawv6_recvmsg(struct sock * sk,struct msghdr * msg,size_t len,int flags,int * addr_len)434 static int rawv6_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
435 int flags, int *addr_len)
436 {
437 struct ipv6_pinfo *np = inet6_sk(sk);
438 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
439 struct sk_buff *skb;
440 size_t copied;
441 int err;
442
443 if (flags & MSG_OOB)
444 return -EOPNOTSUPP;
445
446 if (flags & MSG_ERRQUEUE)
447 return ipv6_recv_error(sk, msg, len, addr_len);
448
449 if (np->rxopt.bits.rxpmtu && READ_ONCE(np->rxpmtu))
450 return ipv6_recv_rxpmtu(sk, msg, len, addr_len);
451
452 skb = skb_recv_datagram(sk, flags, &err);
453 if (!skb)
454 goto out;
455
456 copied = skb->len;
457 if (copied > len) {
458 copied = len;
459 msg->msg_flags |= MSG_TRUNC;
460 }
461
462 if (skb_csum_unnecessary(skb)) {
463 err = skb_copy_datagram_msg(skb, 0, msg, copied);
464 } else if (msg->msg_flags&MSG_TRUNC) {
465 if (__skb_checksum_complete(skb))
466 goto csum_copy_err;
467 err = skb_copy_datagram_msg(skb, 0, msg, copied);
468 } else {
469 err = skb_copy_and_csum_datagram_msg(skb, 0, msg);
470 if (err == -EINVAL)
471 goto csum_copy_err;
472 }
473 if (err)
474 goto out_free;
475
476 /* Copy the address. */
477 if (sin6) {
478 sin6->sin6_family = AF_INET6;
479 sin6->sin6_port = 0;
480 sin6->sin6_addr = ipv6_hdr(skb)->saddr;
481 sin6->sin6_flowinfo = 0;
482 sin6->sin6_scope_id = ipv6_iface_scope_id(&sin6->sin6_addr,
483 inet6_iif(skb));
484 *addr_len = sizeof(*sin6);
485 }
486
487 sock_recv_cmsgs(msg, sk, skb);
488
489 if (np->rxopt.all)
490 ip6_datagram_recv_ctl(sk, msg, skb);
491
492 err = copied;
493 if (flags & MSG_TRUNC)
494 err = skb->len;
495
496 out_free:
497 skb_free_datagram(sk, skb);
498 out:
499 return err;
500
501 csum_copy_err:
502 skb_kill_datagram(sk, skb, flags);
503
504 /* Error for blocking case is chosen to masquerade
505 as some normal condition.
506 */
507 err = (flags&MSG_DONTWAIT) ? -EAGAIN : -EHOSTUNREACH;
508 goto out;
509 }
510
rawv6_push_pending_frames(struct sock * sk,struct flowi6 * fl6,struct raw6_sock * rp)511 static int rawv6_push_pending_frames(struct sock *sk, struct flowi6 *fl6,
512 struct raw6_sock *rp)
513 {
514 struct ipv6_txoptions *opt;
515 struct sk_buff *skb;
516 int err = 0;
517 int offset;
518 int len;
519 int total_len;
520 __wsum tmp_csum;
521 __sum16 csum;
522
523 if (!rp->checksum)
524 goto send;
525
526 skb = skb_peek(&sk->sk_write_queue);
527 if (!skb)
528 goto out;
529
530 offset = rp->offset;
531 total_len = inet_sk(sk)->cork.base.length;
532 opt = inet_sk(sk)->cork.base6.opt;
533 total_len -= opt ? opt->opt_flen : 0;
534
535 if (offset >= total_len - 1) {
536 err = -EINVAL;
537 ip6_flush_pending_frames(sk);
538 goto out;
539 }
540
541 /* should be check HW csum miyazawa */
542 if (skb_queue_len(&sk->sk_write_queue) == 1) {
543 /*
544 * Only one fragment on the socket.
545 */
546 tmp_csum = skb->csum;
547 } else {
548 struct sk_buff *csum_skb = NULL;
549 tmp_csum = 0;
550
551 skb_queue_walk(&sk->sk_write_queue, skb) {
552 tmp_csum = csum_add(tmp_csum, skb->csum);
553
554 if (csum_skb)
555 continue;
556
557 len = skb->len - skb_transport_offset(skb);
558 if (offset >= len) {
559 offset -= len;
560 continue;
561 }
562
563 csum_skb = skb;
564 }
565
566 skb = csum_skb;
567 }
568
569 offset += skb_transport_offset(skb);
570 err = skb_copy_bits(skb, offset, &csum, 2);
571 if (err < 0) {
572 ip6_flush_pending_frames(sk);
573 goto out;
574 }
575
576 /* in case cksum was not initialized */
577 if (unlikely(csum))
578 tmp_csum = csum_sub(tmp_csum, csum_unfold(csum));
579
580 csum = csum_ipv6_magic(&fl6->saddr, &fl6->daddr,
581 total_len, fl6->flowi6_proto, tmp_csum);
582
583 if (csum == 0 && fl6->flowi6_proto == IPPROTO_UDP)
584 csum = CSUM_MANGLED_0;
585
586 BUG_ON(skb_store_bits(skb, offset, &csum, 2));
587
588 send:
589 err = ip6_push_pending_frames(sk);
590 out:
591 return err;
592 }
593
rawv6_send_hdrinc(struct sock * sk,struct msghdr * msg,int length,struct flowi6 * fl6,struct dst_entry ** dstp,unsigned int flags,const struct sockcm_cookie * sockc)594 static int rawv6_send_hdrinc(struct sock *sk, struct msghdr *msg, int length,
595 struct flowi6 *fl6, struct dst_entry **dstp,
596 unsigned int flags, const struct sockcm_cookie *sockc)
597 {
598 struct net *net = sock_net(sk);
599 struct ipv6hdr *iph;
600 struct sk_buff *skb;
601 int err;
602 struct rt6_info *rt = dst_rt6_info(*dstp);
603 int hlen = LL_RESERVED_SPACE(rt->dst.dev);
604 int tlen = rt->dst.dev->needed_tailroom;
605
606 if (length > rt->dst.dev->mtu) {
607 ipv6_local_error(sk, EMSGSIZE, fl6, rt->dst.dev->mtu);
608 return -EMSGSIZE;
609 }
610 if (length < sizeof(struct ipv6hdr))
611 return -EINVAL;
612 if (flags&MSG_PROBE)
613 goto out;
614
615 skb = sock_alloc_send_skb(sk,
616 length + hlen + tlen + 15,
617 flags & MSG_DONTWAIT, &err);
618 if (!skb)
619 goto error;
620 skb_reserve(skb, hlen);
621
622 skb->protocol = htons(ETH_P_IPV6);
623 skb->priority = sockc->priority;
624 skb->mark = sockc->mark;
625 skb_set_delivery_type_by_clockid(skb, sockc->transmit_time, sk->sk_clockid);
626
627 skb_put(skb, length);
628 skb_reset_network_header(skb);
629 iph = ipv6_hdr(skb);
630
631 skb->ip_summed = CHECKSUM_NONE;
632
633 skb_setup_tx_timestamp(skb, sockc);
634
635 if (flags & MSG_CONFIRM)
636 skb_set_dst_pending_confirm(skb, 1);
637
638 skb->transport_header = skb->network_header;
639 err = memcpy_from_msg(iph, msg, length);
640 if (err) {
641 err = -EFAULT;
642 kfree_skb(skb);
643 goto error;
644 }
645
646 skb_dst_set(skb, &rt->dst);
647 *dstp = NULL;
648
649 /* if egress device is enslaved to an L3 master device pass the
650 * skb to its handler for processing
651 */
652 skb = l3mdev_ip6_out(sk, skb);
653 if (unlikely(!skb))
654 return 0;
655
656 /* Acquire rcu_read_lock() in case we need to use rt->rt6i_idev
657 * in the error path. Since skb has been freed, the dst could
658 * have been queued for deletion.
659 */
660 rcu_read_lock();
661 IP6_INC_STATS(net, rt->rt6i_idev, IPSTATS_MIB_OUTREQUESTS);
662 err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT, net, sk, skb,
663 NULL, rt->dst.dev, dst_output);
664 if (err > 0)
665 err = net_xmit_errno(err);
666 if (err) {
667 IP6_INC_STATS(net, rt->rt6i_idev, IPSTATS_MIB_OUTDISCARDS);
668 rcu_read_unlock();
669 goto error_check;
670 }
671 rcu_read_unlock();
672 out:
673 return 0;
674
675 error:
676 IP6_INC_STATS(net, rt->rt6i_idev, IPSTATS_MIB_OUTDISCARDS);
677 error_check:
678 if (err == -ENOBUFS && !inet6_test_bit(RECVERR6, sk))
679 err = 0;
680 return err;
681 }
682
683 struct raw6_frag_vec {
684 struct msghdr *msg;
685 int hlen;
686 char c[4];
687 };
688
rawv6_probe_proto_opt(struct raw6_frag_vec * rfv,struct flowi6 * fl6)689 static int rawv6_probe_proto_opt(struct raw6_frag_vec *rfv, struct flowi6 *fl6)
690 {
691 int err = 0;
692 switch (fl6->flowi6_proto) {
693 case IPPROTO_ICMPV6:
694 rfv->hlen = 2;
695 err = memcpy_from_msg(rfv->c, rfv->msg, rfv->hlen);
696 if (!err) {
697 fl6->fl6_icmp_type = rfv->c[0];
698 fl6->fl6_icmp_code = rfv->c[1];
699 }
700 break;
701 case IPPROTO_MH:
702 rfv->hlen = 4;
703 err = memcpy_from_msg(rfv->c, rfv->msg, rfv->hlen);
704 if (!err)
705 fl6->fl6_mh_type = rfv->c[2];
706 }
707 return err;
708 }
709
raw6_getfrag(void * from,char * to,int offset,int len,int odd,struct sk_buff * skb)710 static int raw6_getfrag(void *from, char *to, int offset, int len, int odd,
711 struct sk_buff *skb)
712 {
713 struct raw6_frag_vec *rfv = from;
714
715 if (offset < rfv->hlen) {
716 int copy = min(rfv->hlen - offset, len);
717
718 if (skb->ip_summed == CHECKSUM_PARTIAL)
719 memcpy(to, rfv->c + offset, copy);
720 else
721 skb->csum = csum_block_add(
722 skb->csum,
723 csum_partial_copy_nocheck(rfv->c + offset,
724 to, copy),
725 odd);
726
727 odd = 0;
728 offset += copy;
729 to += copy;
730 len -= copy;
731
732 if (!len)
733 return 0;
734 }
735
736 offset -= rfv->hlen;
737
738 return ip_generic_getfrag(rfv->msg, to, offset, len, odd, skb);
739 }
740
rawv6_sendmsg(struct sock * sk,struct msghdr * msg,size_t len)741 static int rawv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
742 {
743 struct ipv6_txoptions *opt_to_free = NULL;
744 struct ipv6_txoptions opt_space;
745 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
746 struct in6_addr *daddr, *final_p, final;
747 struct inet_sock *inet = inet_sk(sk);
748 struct ipv6_pinfo *np = inet6_sk(sk);
749 struct raw6_sock *rp = raw6_sk(sk);
750 struct ipv6_txoptions *opt = NULL;
751 struct ip6_flowlabel *flowlabel = NULL;
752 struct dst_entry *dst = NULL;
753 struct raw6_frag_vec rfv;
754 struct flowi6 fl6;
755 struct ipcm6_cookie ipc6;
756 int addr_len = msg->msg_namelen;
757 int hdrincl;
758 u16 proto;
759 int err;
760
761 /* Rough check on arithmetic overflow,
762 better check is made in ip6_append_data().
763 */
764 if (len > INT_MAX)
765 return -EMSGSIZE;
766
767 /* Mirror BSD error message compatibility */
768 if (msg->msg_flags & MSG_OOB)
769 return -EOPNOTSUPP;
770
771 hdrincl = inet_test_bit(HDRINCL, sk);
772
773 ipcm6_init_sk(&ipc6, sk);
774
775 /*
776 * Get and verify the address.
777 */
778 memset(&fl6, 0, sizeof(fl6));
779
780 fl6.flowi6_mark = ipc6.sockc.mark;
781 fl6.flowi6_uid = sk_uid(sk);
782
783 if (sin6) {
784 if (addr_len < SIN6_LEN_RFC2133)
785 return -EINVAL;
786
787 if (sin6->sin6_family && sin6->sin6_family != AF_INET6)
788 return -EAFNOSUPPORT;
789
790 /* port is the proto value [0..255] carried in nexthdr */
791 proto = ntohs(sin6->sin6_port);
792
793 if (!proto)
794 proto = inet->inet_num;
795 else if (proto != inet->inet_num &&
796 inet->inet_num != IPPROTO_RAW)
797 return -EINVAL;
798
799 if (proto > 255)
800 return -EINVAL;
801
802 daddr = &sin6->sin6_addr;
803 if (inet6_test_bit(SNDFLOW, sk)) {
804 fl6.flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK;
805 if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) {
806 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
807 if (IS_ERR(flowlabel))
808 return -EINVAL;
809 }
810 }
811
812 /*
813 * Otherwise it will be difficult to maintain
814 * sk->sk_dst_cache.
815 */
816 if (sk->sk_state == TCP_ESTABLISHED &&
817 ipv6_addr_equal(daddr, &sk->sk_v6_daddr))
818 daddr = &sk->sk_v6_daddr;
819
820 if (addr_len >= sizeof(struct sockaddr_in6) &&
821 sin6->sin6_scope_id &&
822 __ipv6_addr_needs_scope_id(__ipv6_addr_type(daddr)))
823 fl6.flowi6_oif = sin6->sin6_scope_id;
824 } else {
825 if (sk->sk_state != TCP_ESTABLISHED)
826 return -EDESTADDRREQ;
827
828 proto = inet->inet_num;
829 daddr = &sk->sk_v6_daddr;
830 fl6.flowlabel = np->flow_label;
831 }
832
833 if (fl6.flowi6_oif == 0)
834 fl6.flowi6_oif = sk->sk_bound_dev_if;
835
836 if (msg->msg_controllen) {
837 opt = &opt_space;
838 memset(opt, 0, sizeof(struct ipv6_txoptions));
839 opt->tot_len = sizeof(struct ipv6_txoptions);
840 ipc6.opt = opt;
841
842 err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, &fl6, &ipc6);
843 if (err < 0) {
844 fl6_sock_release(flowlabel);
845 return err;
846 }
847 if ((fl6.flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) {
848 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
849 if (IS_ERR(flowlabel))
850 return -EINVAL;
851 }
852 if (!(opt->opt_nflen|opt->opt_flen))
853 opt = NULL;
854 }
855 if (!opt) {
856 opt = txopt_get(np);
857 opt_to_free = opt;
858 }
859 if (flowlabel)
860 opt = fl6_merge_options(&opt_space, flowlabel, opt);
861 opt = ipv6_fixup_options(&opt_space, opt);
862
863 fl6.flowi6_proto = proto;
864 fl6.flowi6_mark = ipc6.sockc.mark;
865
866 if (!hdrincl) {
867 rfv.msg = msg;
868 rfv.hlen = 0;
869 err = rawv6_probe_proto_opt(&rfv, &fl6);
870 if (err)
871 goto out;
872 }
873
874 if (!ipv6_addr_any(daddr))
875 fl6.daddr = *daddr;
876 else
877 fl6.daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */
878 if (ipv6_addr_any(&fl6.saddr) && !ipv6_addr_any(&np->saddr))
879 fl6.saddr = np->saddr;
880
881 final_p = fl6_update_dst(&fl6, opt, &final);
882
883 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
884 fl6.flowi6_oif = READ_ONCE(np->mcast_oif);
885 else if (!fl6.flowi6_oif)
886 fl6.flowi6_oif = READ_ONCE(np->ucast_oif);
887 security_sk_classify_flow(sk, flowi6_to_flowi_common(&fl6));
888
889 if (hdrincl)
890 fl6.flowi6_flags |= FLOWI_FLAG_KNOWN_NH;
891
892 fl6.flowlabel = ip6_make_flowinfo(ipc6.tclass, fl6.flowlabel);
893
894 dst = ip6_dst_lookup_flow(sock_net(sk), sk, &fl6, final_p);
895 if (IS_ERR(dst)) {
896 err = PTR_ERR(dst);
897 goto out;
898 }
899 if (ipc6.hlimit < 0)
900 ipc6.hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
901
902 if (msg->msg_flags&MSG_CONFIRM)
903 goto do_confirm;
904
905 back_from_confirm:
906 if (hdrincl)
907 err = rawv6_send_hdrinc(sk, msg, len, &fl6, &dst,
908 msg->msg_flags, &ipc6.sockc);
909 else {
910 ipc6.opt = opt;
911 lock_sock(sk);
912 err = ip6_append_data(sk, raw6_getfrag, &rfv,
913 len, 0, &ipc6, &fl6, dst_rt6_info(dst),
914 msg->msg_flags);
915
916 if (err)
917 ip6_flush_pending_frames(sk);
918 else if (!(msg->msg_flags & MSG_MORE))
919 err = rawv6_push_pending_frames(sk, &fl6, rp);
920 release_sock(sk);
921 }
922 done:
923 dst_release(dst);
924 out:
925 fl6_sock_release(flowlabel);
926 txopt_put(opt_to_free);
927 return err < 0 ? err : len;
928 do_confirm:
929 if (msg->msg_flags & MSG_PROBE)
930 dst_confirm_neigh(dst, &fl6.daddr);
931 if (!(msg->msg_flags & MSG_PROBE) || len)
932 goto back_from_confirm;
933 err = 0;
934 goto done;
935 }
936
rawv6_seticmpfilter(struct sock * sk,int optname,sockptr_t optval,int optlen)937 static int rawv6_seticmpfilter(struct sock *sk, int optname,
938 sockptr_t optval, int optlen)
939 {
940 switch (optname) {
941 case ICMPV6_FILTER:
942 if (optlen > sizeof(struct icmp6_filter))
943 optlen = sizeof(struct icmp6_filter);
944 if (copy_from_sockptr(&raw6_sk(sk)->filter, optval, optlen))
945 return -EFAULT;
946 return 0;
947 default:
948 return -ENOPROTOOPT;
949 }
950
951 return 0;
952 }
953
rawv6_geticmpfilter(struct sock * sk,int optname,char __user * optval,int __user * optlen)954 static int rawv6_geticmpfilter(struct sock *sk, int optname,
955 char __user *optval, int __user *optlen)
956 {
957 int len;
958
959 switch (optname) {
960 case ICMPV6_FILTER:
961 if (get_user(len, optlen))
962 return -EFAULT;
963 if (len < 0)
964 return -EINVAL;
965 if (len > sizeof(struct icmp6_filter))
966 len = sizeof(struct icmp6_filter);
967 if (put_user(len, optlen))
968 return -EFAULT;
969 if (copy_to_user(optval, &raw6_sk(sk)->filter, len))
970 return -EFAULT;
971 return 0;
972 default:
973 return -ENOPROTOOPT;
974 }
975
976 return 0;
977 }
978
979
do_rawv6_setsockopt(struct sock * sk,int level,int optname,sockptr_t optval,unsigned int optlen)980 static int do_rawv6_setsockopt(struct sock *sk, int level, int optname,
981 sockptr_t optval, unsigned int optlen)
982 {
983 struct raw6_sock *rp = raw6_sk(sk);
984 int val;
985
986 if (optlen < sizeof(val))
987 return -EINVAL;
988
989 if (copy_from_sockptr(&val, optval, sizeof(val)))
990 return -EFAULT;
991
992 switch (optname) {
993 case IPV6_HDRINCL:
994 if (sk->sk_type != SOCK_RAW)
995 return -EINVAL;
996 inet_assign_bit(HDRINCL, sk, val);
997 return 0;
998 case IPV6_CHECKSUM:
999 if (inet_sk(sk)->inet_num == IPPROTO_ICMPV6 &&
1000 level == IPPROTO_IPV6) {
1001 /*
1002 * RFC3542 tells that IPV6_CHECKSUM socket
1003 * option in the IPPROTO_IPV6 level is not
1004 * allowed on ICMPv6 sockets.
1005 * If you want to set it, use IPPROTO_RAW
1006 * level IPV6_CHECKSUM socket option
1007 * (Linux extension).
1008 */
1009 return -EINVAL;
1010 }
1011
1012 /* You may get strange result with a positive odd offset;
1013 RFC2292bis agrees with me. */
1014 if (val > 0 && (val&1))
1015 return -EINVAL;
1016 if (val < 0) {
1017 rp->checksum = 0;
1018 } else {
1019 rp->checksum = 1;
1020 rp->offset = val;
1021 }
1022
1023 return 0;
1024
1025 default:
1026 return -ENOPROTOOPT;
1027 }
1028 }
1029
rawv6_setsockopt(struct sock * sk,int level,int optname,sockptr_t optval,unsigned int optlen)1030 static int rawv6_setsockopt(struct sock *sk, int level, int optname,
1031 sockptr_t optval, unsigned int optlen)
1032 {
1033 switch (level) {
1034 case SOL_RAW:
1035 break;
1036
1037 case SOL_ICMPV6:
1038 if (inet_sk(sk)->inet_num != IPPROTO_ICMPV6)
1039 return -EOPNOTSUPP;
1040 return rawv6_seticmpfilter(sk, optname, optval, optlen);
1041 case SOL_IPV6:
1042 if (optname == IPV6_CHECKSUM ||
1043 optname == IPV6_HDRINCL)
1044 break;
1045 fallthrough;
1046 default:
1047 return ipv6_setsockopt(sk, level, optname, optval, optlen);
1048 }
1049
1050 return do_rawv6_setsockopt(sk, level, optname, optval, optlen);
1051 }
1052
do_rawv6_getsockopt(struct sock * sk,int level,int optname,char __user * optval,int __user * optlen)1053 static int do_rawv6_getsockopt(struct sock *sk, int level, int optname,
1054 char __user *optval, int __user *optlen)
1055 {
1056 struct raw6_sock *rp = raw6_sk(sk);
1057 int val, len;
1058
1059 if (get_user(len, optlen))
1060 return -EFAULT;
1061
1062 switch (optname) {
1063 case IPV6_HDRINCL:
1064 val = inet_test_bit(HDRINCL, sk);
1065 break;
1066 case IPV6_CHECKSUM:
1067 /*
1068 * We allow getsockopt() for IPPROTO_IPV6-level
1069 * IPV6_CHECKSUM socket option on ICMPv6 sockets
1070 * since RFC3542 is silent about it.
1071 */
1072 if (rp->checksum == 0)
1073 val = -1;
1074 else
1075 val = rp->offset;
1076 break;
1077
1078 default:
1079 return -ENOPROTOOPT;
1080 }
1081
1082 len = min_t(unsigned int, sizeof(int), len);
1083
1084 if (put_user(len, optlen))
1085 return -EFAULT;
1086 if (copy_to_user(optval, &val, len))
1087 return -EFAULT;
1088 return 0;
1089 }
1090
rawv6_getsockopt(struct sock * sk,int level,int optname,char __user * optval,int __user * optlen)1091 static int rawv6_getsockopt(struct sock *sk, int level, int optname,
1092 char __user *optval, int __user *optlen)
1093 {
1094 switch (level) {
1095 case SOL_RAW:
1096 break;
1097
1098 case SOL_ICMPV6:
1099 if (inet_sk(sk)->inet_num != IPPROTO_ICMPV6)
1100 return -EOPNOTSUPP;
1101 return rawv6_geticmpfilter(sk, optname, optval, optlen);
1102 case SOL_IPV6:
1103 if (optname == IPV6_CHECKSUM ||
1104 optname == IPV6_HDRINCL)
1105 break;
1106 fallthrough;
1107 default:
1108 return ipv6_getsockopt(sk, level, optname, optval, optlen);
1109 }
1110
1111 return do_rawv6_getsockopt(sk, level, optname, optval, optlen);
1112 }
1113
rawv6_ioctl(struct sock * sk,int cmd,int * karg)1114 static int rawv6_ioctl(struct sock *sk, int cmd, int *karg)
1115 {
1116 switch (cmd) {
1117 case SIOCOUTQ: {
1118 *karg = sk_wmem_alloc_get(sk);
1119 return 0;
1120 }
1121 case SIOCINQ: {
1122 struct sk_buff *skb;
1123
1124 spin_lock_bh(&sk->sk_receive_queue.lock);
1125 skb = skb_peek(&sk->sk_receive_queue);
1126 if (skb)
1127 *karg = skb->len;
1128 else
1129 *karg = 0;
1130 spin_unlock_bh(&sk->sk_receive_queue.lock);
1131 return 0;
1132 }
1133
1134 default:
1135 #ifdef CONFIG_IPV6_MROUTE
1136 return ip6mr_ioctl(sk, cmd, karg);
1137 #else
1138 return -ENOIOCTLCMD;
1139 #endif
1140 }
1141 }
1142
1143 #ifdef CONFIG_COMPAT
compat_rawv6_ioctl(struct sock * sk,unsigned int cmd,unsigned long arg)1144 static int compat_rawv6_ioctl(struct sock *sk, unsigned int cmd, unsigned long arg)
1145 {
1146 switch (cmd) {
1147 case SIOCOUTQ:
1148 case SIOCINQ:
1149 return -ENOIOCTLCMD;
1150 default:
1151 #ifdef CONFIG_IPV6_MROUTE
1152 return ip6mr_compat_ioctl(sk, cmd, compat_ptr(arg));
1153 #else
1154 return -ENOIOCTLCMD;
1155 #endif
1156 }
1157 }
1158 #endif
1159
rawv6_close(struct sock * sk,long timeout)1160 static void rawv6_close(struct sock *sk, long timeout)
1161 {
1162 if (inet_sk(sk)->inet_num == IPPROTO_RAW)
1163 ip6_ra_control(sk, -1);
1164 ip6mr_sk_done(sk);
1165 sk_common_release(sk);
1166 }
1167
raw6_destroy(struct sock * sk)1168 static void raw6_destroy(struct sock *sk)
1169 {
1170 lock_sock(sk);
1171 ip6_flush_pending_frames(sk);
1172 release_sock(sk);
1173 }
1174
rawv6_init_sk(struct sock * sk)1175 static int rawv6_init_sk(struct sock *sk)
1176 {
1177 struct raw6_sock *rp = raw6_sk(sk);
1178
1179 sk->sk_drop_counters = &rp->drop_counters;
1180 switch (inet_sk(sk)->inet_num) {
1181 case IPPROTO_ICMPV6:
1182 rp->checksum = 1;
1183 rp->offset = 2;
1184 break;
1185 case IPPROTO_MH:
1186 rp->checksum = 1;
1187 rp->offset = 4;
1188 break;
1189 default:
1190 break;
1191 }
1192 return 0;
1193 }
1194
1195 struct proto rawv6_prot = {
1196 .name = "RAWv6",
1197 .owner = THIS_MODULE,
1198 .close = rawv6_close,
1199 .destroy = raw6_destroy,
1200 .connect = ip6_datagram_connect_v6_only,
1201 .disconnect = __udp_disconnect,
1202 .ioctl = rawv6_ioctl,
1203 .init = rawv6_init_sk,
1204 .setsockopt = rawv6_setsockopt,
1205 .getsockopt = rawv6_getsockopt,
1206 .sendmsg = rawv6_sendmsg,
1207 .recvmsg = rawv6_recvmsg,
1208 .bind = rawv6_bind,
1209 .backlog_rcv = rawv6_rcv_skb,
1210 .hash = raw_hash_sk,
1211 .unhash = raw_unhash_sk,
1212 .obj_size = sizeof(struct raw6_sock),
1213 .ipv6_pinfo_offset = offsetof(struct raw6_sock, inet6),
1214 .useroffset = offsetof(struct raw6_sock, filter),
1215 .usersize = sizeof_field(struct raw6_sock, filter),
1216 .h.raw_hash = &raw_v6_hashinfo,
1217 #ifdef CONFIG_COMPAT
1218 .compat_ioctl = compat_rawv6_ioctl,
1219 #endif
1220 .diag_destroy = raw_abort,
1221 };
1222
1223 #ifdef CONFIG_PROC_FS
raw6_seq_show(struct seq_file * seq,void * v)1224 static int raw6_seq_show(struct seq_file *seq, void *v)
1225 {
1226 if (v == SEQ_START_TOKEN) {
1227 seq_puts(seq, IPV6_SEQ_DGRAM_HEADER);
1228 } else {
1229 struct sock *sp = v;
1230 __u16 srcp = inet_sk(sp)->inet_num;
1231 ip6_dgram_sock_seq_show(seq, v, srcp, 0,
1232 raw_seq_private(seq)->bucket);
1233 }
1234 return 0;
1235 }
1236
1237 static const struct seq_operations raw6_seq_ops = {
1238 .start = raw_seq_start,
1239 .next = raw_seq_next,
1240 .stop = raw_seq_stop,
1241 .show = raw6_seq_show,
1242 };
1243
raw6_init_net(struct net * net)1244 static int __net_init raw6_init_net(struct net *net)
1245 {
1246 if (!proc_create_net_data("raw6", 0444, net->proc_net, &raw6_seq_ops,
1247 sizeof(struct raw_iter_state), &raw_v6_hashinfo))
1248 return -ENOMEM;
1249
1250 return 0;
1251 }
1252
raw6_exit_net(struct net * net)1253 static void __net_exit raw6_exit_net(struct net *net)
1254 {
1255 remove_proc_entry("raw6", net->proc_net);
1256 }
1257
1258 static struct pernet_operations raw6_net_ops = {
1259 .init = raw6_init_net,
1260 .exit = raw6_exit_net,
1261 };
1262
raw6_proc_init(void)1263 int __init raw6_proc_init(void)
1264 {
1265 return register_pernet_subsys(&raw6_net_ops);
1266 }
1267
raw6_proc_exit(void)1268 void raw6_proc_exit(void)
1269 {
1270 unregister_pernet_subsys(&raw6_net_ops);
1271 }
1272 #endif /* CONFIG_PROC_FS */
1273
1274 /* Same as inet6_dgram_ops, sans udp_poll. */
1275 const struct proto_ops inet6_sockraw_ops = {
1276 .family = PF_INET6,
1277 .owner = THIS_MODULE,
1278 .release = inet6_release,
1279 .bind = inet6_bind,
1280 .connect = inet_dgram_connect, /* ok */
1281 .socketpair = sock_no_socketpair, /* a do nothing */
1282 .accept = sock_no_accept, /* a do nothing */
1283 .getname = inet6_getname,
1284 .poll = datagram_poll, /* ok */
1285 .ioctl = inet6_ioctl, /* must change */
1286 .gettstamp = sock_gettstamp,
1287 .listen = sock_no_listen, /* ok */
1288 .shutdown = inet_shutdown, /* ok */
1289 .setsockopt = sock_common_setsockopt, /* ok */
1290 .getsockopt = sock_common_getsockopt, /* ok */
1291 .sendmsg = inet_sendmsg, /* ok */
1292 .recvmsg = sock_common_recvmsg, /* ok */
1293 .mmap = sock_no_mmap,
1294 #ifdef CONFIG_COMPAT
1295 .compat_ioctl = inet6_compat_ioctl,
1296 #endif
1297 };
1298
1299 static struct inet_protosw rawv6_protosw = {
1300 .type = SOCK_RAW,
1301 .protocol = IPPROTO_IP, /* wild card */
1302 .prot = &rawv6_prot,
1303 .ops = &inet6_sockraw_ops,
1304 .flags = INET_PROTOSW_REUSE,
1305 };
1306
rawv6_init(void)1307 int __init rawv6_init(void)
1308 {
1309 return inet6_register_protosw(&rawv6_protosw);
1310 }
1311
rawv6_exit(void)1312 void rawv6_exit(void)
1313 {
1314 inet6_unregister_protosw(&rawv6_protosw);
1315 }
1316