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_sdif(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 reason = sock_queue_rcv_skb_reason(sk, skb);
373 if (reason) {
374 sk_skb_reason_drop(sk, skb, reason);
375 return NET_RX_DROP;
376 }
377
378 return 0;
379 }
380
381 /*
382 * This is next to useless...
383 * if we demultiplex in network layer we don't need the extra call
384 * just to queue the skb...
385 * maybe we could have the network decide upon a hint if it
386 * should call raw_rcv for demultiplexing
387 */
rawv6_rcv(struct sock * sk,struct sk_buff * skb)388 int rawv6_rcv(struct sock *sk, struct sk_buff *skb)
389 {
390 struct inet_sock *inet = inet_sk(sk);
391 struct raw6_sock *rp = raw6_sk(sk);
392
393 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) {
394 sk_drops_inc(sk);
395 sk_skb_reason_drop(sk, skb, SKB_DROP_REASON_XFRM_POLICY);
396 return NET_RX_DROP;
397 }
398 nf_reset_ct(skb);
399
400 if (!rp->checksum)
401 skb->ip_summed = CHECKSUM_UNNECESSARY;
402
403 if (skb->ip_summed == CHECKSUM_COMPLETE) {
404 skb_postpull_rcsum(skb, skb_network_header(skb),
405 skb_network_header_len(skb));
406 if (!csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
407 &ipv6_hdr(skb)->daddr,
408 skb->len, inet->inet_num, skb->csum))
409 skb->ip_summed = CHECKSUM_UNNECESSARY;
410 }
411 if (!skb_csum_unnecessary(skb))
412 skb->csum = ~csum_unfold(csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
413 &ipv6_hdr(skb)->daddr,
414 skb->len,
415 inet->inet_num, 0));
416
417 if (inet_test_bit(HDRINCL, sk)) {
418 if (skb_checksum_complete(skb)) {
419 sk_drops_inc(sk);
420 sk_skb_reason_drop(sk, skb, SKB_DROP_REASON_SKB_CSUM);
421 return NET_RX_DROP;
422 }
423 }
424
425 rawv6_rcv_skb(sk, skb);
426 return 0;
427 }
428
429
430 /*
431 * This should be easy, if there is something there
432 * we return it, otherwise we block.
433 */
434
rawv6_recvmsg(struct sock * sk,struct msghdr * msg,size_t len,int flags)435 static int rawv6_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
436 int flags)
437 {
438 struct ipv6_pinfo *np = inet6_sk(sk);
439 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
440 struct sk_buff *skb;
441 size_t copied;
442 int err;
443
444 if (flags & MSG_OOB)
445 return -EOPNOTSUPP;
446
447 if (flags & MSG_ERRQUEUE)
448 return ipv6_recv_error(sk, msg, len);
449
450 if (np->rxopt.bits.rxpmtu && READ_ONCE(np->rxpmtu))
451 return ipv6_recv_rxpmtu(sk, msg, len);
452
453 skb = skb_recv_datagram(sk, flags, &err);
454 if (!skb)
455 goto out;
456
457 copied = skb->len;
458 if (copied > len) {
459 copied = len;
460 msg->msg_flags |= MSG_TRUNC;
461 }
462
463 if (skb_csum_unnecessary(skb)) {
464 err = skb_copy_datagram_msg(skb, 0, msg, copied);
465 } else if (msg->msg_flags&MSG_TRUNC) {
466 if (__skb_checksum_complete(skb))
467 goto csum_copy_err;
468 err = skb_copy_datagram_msg(skb, 0, msg, copied);
469 } else {
470 err = skb_copy_and_csum_datagram_msg(skb, 0, msg);
471 if (err == -EINVAL)
472 goto csum_copy_err;
473 }
474 if (err)
475 goto out_free;
476
477 /* Copy the address. */
478 if (sin6) {
479 sin6->sin6_family = AF_INET6;
480 sin6->sin6_port = 0;
481 sin6->sin6_addr = ipv6_hdr(skb)->saddr;
482 sin6->sin6_flowinfo = 0;
483 sin6->sin6_scope_id = ipv6_iface_scope_id(&sin6->sin6_addr,
484 inet6_iif(skb));
485 msg->msg_namelen = sizeof(*sin6);
486 }
487
488 sock_recv_cmsgs(msg, sk, skb);
489
490 if (np->rxopt.all)
491 ip6_datagram_recv_ctl(sk, msg, skb);
492
493 err = copied;
494 if (flags & MSG_TRUNC)
495 err = skb->len;
496
497 out_free:
498 skb_free_datagram(sk, skb);
499 out:
500 return err;
501
502 csum_copy_err:
503 skb_kill_datagram(sk, skb, flags);
504
505 /* Error for blocking case is chosen to masquerade
506 as some normal condition.
507 */
508 err = (flags&MSG_DONTWAIT) ? -EAGAIN : -EHOSTUNREACH;
509 goto out;
510 }
511
rawv6_push_pending_frames(struct sock * sk,struct flowi6 * fl6,struct raw6_sock * rp)512 static int rawv6_push_pending_frames(struct sock *sk, struct flowi6 *fl6,
513 struct raw6_sock *rp)
514 {
515 struct ipv6_txoptions *opt;
516 struct sk_buff *skb;
517 int err = 0;
518 int offset;
519 int len;
520 int total_len;
521 __wsum tmp_csum;
522 __sum16 csum;
523
524 if (!rp->checksum)
525 goto send;
526
527 skb = skb_peek(&sk->sk_write_queue);
528 if (!skb)
529 goto out;
530
531 offset = rp->offset;
532 total_len = inet_sk(sk)->cork.base.length;
533 opt = inet_sk(sk)->cork.base6.opt;
534 total_len -= opt ? opt->opt_flen : 0;
535
536 if (offset >= total_len - 1) {
537 err = -EINVAL;
538 ip6_flush_pending_frames(sk);
539 goto out;
540 }
541
542 /* should be check HW csum miyazawa */
543 if (skb_queue_len(&sk->sk_write_queue) == 1) {
544 /*
545 * Only one fragment on the socket.
546 */
547 tmp_csum = skb->csum;
548 } else {
549 struct sk_buff *csum_skb = NULL;
550 tmp_csum = 0;
551
552 skb_queue_walk(&sk->sk_write_queue, skb) {
553 tmp_csum = csum_add(tmp_csum, skb->csum);
554
555 if (csum_skb)
556 continue;
557
558 len = skb->len - skb_transport_offset(skb);
559 if (offset >= len) {
560 offset -= len;
561 continue;
562 }
563
564 csum_skb = skb;
565 }
566
567 skb = csum_skb;
568 }
569
570 offset += skb_transport_offset(skb);
571 err = skb_copy_bits(skb, offset, &csum, 2);
572 if (err < 0) {
573 ip6_flush_pending_frames(sk);
574 goto out;
575 }
576
577 /* in case cksum was not initialized */
578 if (unlikely(csum))
579 tmp_csum = csum_sub(tmp_csum, csum_unfold(csum));
580
581 csum = csum_ipv6_magic(&fl6->saddr, &fl6->daddr,
582 total_len, fl6->flowi6_proto, tmp_csum);
583
584 if (csum == 0 && fl6->flowi6_proto == IPPROTO_UDP)
585 csum = CSUM_MANGLED_0;
586
587 BUG_ON(skb_store_bits(skb, offset, &csum, 2));
588
589 send:
590 err = ip6_push_pending_frames(sk);
591 out:
592 return err;
593 }
594
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)595 static int rawv6_send_hdrinc(struct sock *sk, struct msghdr *msg, int length,
596 struct flowi6 *fl6, struct dst_entry **dstp,
597 unsigned int flags, const struct sockcm_cookie *sockc)
598 {
599 struct net *net = sock_net(sk);
600 struct ipv6hdr *iph;
601 struct sk_buff *skb;
602 int err;
603 struct rt6_info *rt = dst_rt6_info(*dstp);
604 int hlen = LL_RESERVED_SPACE(rt->dst.dev);
605 int tlen = rt->dst.dev->needed_tailroom;
606
607 if (length > rt->dst.dev->mtu) {
608 ipv6_local_error(sk, EMSGSIZE, fl6, rt->dst.dev->mtu);
609 return -EMSGSIZE;
610 }
611 if (length < sizeof(struct ipv6hdr))
612 return -EINVAL;
613 if (flags&MSG_PROBE)
614 goto out;
615
616 skb = sock_alloc_send_skb(sk,
617 length + hlen + tlen + 15,
618 flags & MSG_DONTWAIT, &err);
619 if (!skb)
620 goto error;
621 skb_reserve(skb, hlen);
622
623 skb->protocol = htons(ETH_P_IPV6);
624 skb->priority = sockc->priority;
625 skb->mark = sockc->mark;
626 skb_set_delivery_type_by_clockid(skb, sockc->transmit_time, sk->sk_clockid);
627
628 skb_put(skb, length);
629 skb_reset_network_header(skb);
630 iph = ipv6_hdr(skb);
631
632 skb->ip_summed = CHECKSUM_NONE;
633
634 skb_setup_tx_timestamp(skb, sockc);
635
636 if (flags & MSG_CONFIRM)
637 skb_set_dst_pending_confirm(skb, 1);
638
639 skb->transport_header = skb->network_header;
640 err = memcpy_from_msg(iph, msg, length);
641 if (err) {
642 err = -EFAULT;
643 kfree_skb(skb);
644 goto error;
645 }
646
647 skb_dst_set(skb, &rt->dst);
648 *dstp = NULL;
649
650 /* if egress device is enslaved to an L3 master device pass the
651 * skb to its handler for processing
652 */
653 skb = l3mdev_ip6_out(sk, skb);
654 if (unlikely(!skb))
655 return 0;
656
657 /* Acquire rcu_read_lock() in case we need to use rt->rt6i_idev
658 * in the error path. Since skb has been freed, the dst could
659 * have been queued for deletion.
660 */
661 rcu_read_lock();
662 IP6_INC_STATS(net, rt->rt6i_idev, IPSTATS_MIB_OUTREQUESTS);
663 err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT, net, sk, skb,
664 NULL, rt->dst.dev, dst_output);
665 if (err > 0)
666 err = net_xmit_errno(err);
667 if (err) {
668 IP6_INC_STATS(net, rt->rt6i_idev, IPSTATS_MIB_OUTDISCARDS);
669 rcu_read_unlock();
670 goto error_check;
671 }
672 rcu_read_unlock();
673 out:
674 return 0;
675
676 error:
677 IP6_INC_STATS(net, rt->rt6i_idev, IPSTATS_MIB_OUTDISCARDS);
678 error_check:
679 if (err == -ENOBUFS && !inet6_test_bit(RECVERR6, sk))
680 err = 0;
681 return err;
682 }
683
684 struct raw6_frag_vec {
685 struct msghdr *msg;
686 int hlen;
687 char c[4];
688 };
689
rawv6_probe_proto_opt(struct raw6_frag_vec * rfv,struct flowi6 * fl6)690 static int rawv6_probe_proto_opt(struct raw6_frag_vec *rfv, struct flowi6 *fl6)
691 {
692 int err = 0;
693 switch (fl6->flowi6_proto) {
694 case IPPROTO_ICMPV6:
695 rfv->hlen = 2;
696 err = memcpy_from_msg(rfv->c, rfv->msg, rfv->hlen);
697 if (!err) {
698 fl6->fl6_icmp_type = rfv->c[0];
699 fl6->fl6_icmp_code = rfv->c[1];
700 }
701 break;
702 case IPPROTO_MH:
703 rfv->hlen = 4;
704 err = memcpy_from_msg(rfv->c, rfv->msg, rfv->hlen);
705 if (!err)
706 fl6->fl6_mh_type = rfv->c[2];
707 }
708 return err;
709 }
710
raw6_getfrag(void * from,char * to,int offset,int len,int odd,struct sk_buff * skb)711 static int raw6_getfrag(void *from, char *to, int offset, int len, int odd,
712 struct sk_buff *skb)
713 {
714 struct raw6_frag_vec *rfv = from;
715
716 if (offset < rfv->hlen) {
717 int copy = min(rfv->hlen - offset, len);
718
719 if (skb->ip_summed == CHECKSUM_PARTIAL)
720 memcpy(to, rfv->c + offset, copy);
721 else
722 skb->csum = csum_block_add(
723 skb->csum,
724 csum_partial_copy_nocheck(rfv->c + offset,
725 to, copy),
726 odd);
727
728 odd = 0;
729 offset += copy;
730 to += copy;
731 len -= copy;
732
733 if (!len)
734 return 0;
735 }
736
737 offset -= rfv->hlen;
738
739 return ip_generic_getfrag(rfv->msg, to, offset, len, odd, skb);
740 }
741
rawv6_sendmsg(struct sock * sk,struct msghdr * msg,size_t len)742 static int rawv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
743 {
744 struct ipv6_txoptions *opt_to_free = NULL;
745 struct ipv6_txoptions opt_space;
746 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
747 struct in6_addr *daddr, *final_p, final;
748 struct inet_sock *inet = inet_sk(sk);
749 struct ipv6_pinfo *np = inet6_sk(sk);
750 struct raw6_sock *rp = raw6_sk(sk);
751 struct ipv6_txoptions *opt = NULL;
752 struct ip6_flowlabel *flowlabel = NULL;
753 struct dst_entry *dst = NULL;
754 struct raw6_frag_vec rfv;
755 struct flowi6 fl6;
756 struct ipcm6_cookie ipc6;
757 int addr_len = msg->msg_namelen;
758 int hdrincl;
759 u16 proto;
760 int err;
761
762 /* Rough check on arithmetic overflow,
763 better check is made in ip6_append_data().
764 */
765 if (len > INT_MAX)
766 return -EMSGSIZE;
767
768 /* Mirror BSD error message compatibility */
769 if (msg->msg_flags & MSG_OOB)
770 return -EOPNOTSUPP;
771
772 hdrincl = inet_test_bit(HDRINCL, sk);
773
774 ipcm6_init_sk(&ipc6, sk);
775
776 /*
777 * Get and verify the address.
778 */
779 memset(&fl6, 0, sizeof(fl6));
780
781 fl6.flowi6_mark = ipc6.sockc.mark;
782 fl6.flowi6_uid = sk_uid(sk);
783
784 if (sin6) {
785 if (addr_len < SIN6_LEN_RFC2133)
786 return -EINVAL;
787
788 if (sin6->sin6_family && sin6->sin6_family != AF_INET6)
789 return -EAFNOSUPPORT;
790
791 /* port is the proto value [0..255] carried in nexthdr */
792 proto = ntohs(sin6->sin6_port);
793
794 if (!proto)
795 proto = inet->inet_num;
796 else if (proto != inet->inet_num &&
797 inet->inet_num != IPPROTO_RAW)
798 return -EINVAL;
799
800 if (proto > 255)
801 return -EINVAL;
802
803 daddr = &sin6->sin6_addr;
804 if (inet6_test_bit(SNDFLOW, sk)) {
805 fl6.flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK;
806 if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) {
807 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
808 if (IS_ERR(flowlabel))
809 return -EINVAL;
810 }
811 }
812
813 /*
814 * Otherwise it will be difficult to maintain
815 * sk->sk_dst_cache.
816 */
817 if (sk->sk_state == TCP_ESTABLISHED &&
818 ipv6_addr_equal(daddr, &sk->sk_v6_daddr))
819 daddr = &sk->sk_v6_daddr;
820
821 if (addr_len >= sizeof(struct sockaddr_in6) &&
822 sin6->sin6_scope_id &&
823 __ipv6_addr_needs_scope_id(__ipv6_addr_type(daddr)))
824 fl6.flowi6_oif = sin6->sin6_scope_id;
825 } else {
826 if (sk->sk_state != TCP_ESTABLISHED)
827 return -EDESTADDRREQ;
828
829 proto = inet->inet_num;
830 daddr = &sk->sk_v6_daddr;
831 fl6.flowlabel = np->flow_label;
832 }
833
834 if (fl6.flowi6_oif == 0)
835 fl6.flowi6_oif = sk->sk_bound_dev_if;
836
837 if (msg->msg_controllen) {
838 opt = &opt_space;
839 memset(opt, 0, sizeof(struct ipv6_txoptions));
840 opt->tot_len = sizeof(struct ipv6_txoptions);
841 ipc6.opt = opt;
842
843 err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, &fl6, &ipc6);
844 if (err < 0) {
845 fl6_sock_release(flowlabel);
846 return err;
847 }
848 if ((fl6.flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) {
849 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
850 if (IS_ERR(flowlabel))
851 return -EINVAL;
852 }
853 if (!(opt->opt_nflen|opt->opt_flen))
854 opt = NULL;
855 }
856 if (!opt) {
857 opt = txopt_get(np);
858 opt_to_free = opt;
859 }
860 if (flowlabel)
861 opt = fl6_merge_options(&opt_space, flowlabel, opt);
862 opt = ipv6_fixup_options(&opt_space, opt);
863
864 fl6.flowi6_proto = proto;
865 fl6.flowi6_mark = ipc6.sockc.mark;
866
867 if (!hdrincl) {
868 rfv.msg = msg;
869 rfv.hlen = 0;
870 err = rawv6_probe_proto_opt(&rfv, &fl6);
871 if (err)
872 goto out;
873 }
874
875 if (!ipv6_addr_any(daddr))
876 fl6.daddr = *daddr;
877 else
878 fl6.daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */
879 if (ipv6_addr_any(&fl6.saddr) && !ipv6_addr_any(&np->saddr))
880 fl6.saddr = np->saddr;
881
882 final_p = fl6_update_dst(&fl6, opt, &final);
883
884 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
885 fl6.flowi6_oif = READ_ONCE(np->mcast_oif);
886 else if (!fl6.flowi6_oif)
887 fl6.flowi6_oif = READ_ONCE(np->ucast_oif);
888 security_sk_classify_flow(sk, flowi6_to_flowi_common(&fl6));
889
890 if (hdrincl)
891 fl6.flowi6_flags |= FLOWI_FLAG_KNOWN_NH;
892
893 fl6.flowlabel = ip6_make_flowinfo(ipc6.tclass, fl6.flowlabel);
894
895 dst = ip6_dst_lookup_flow(sock_net(sk), sk, &fl6, final_p);
896 if (IS_ERR(dst)) {
897 err = PTR_ERR(dst);
898 goto out;
899 }
900 if (ipc6.hlimit < 0)
901 ipc6.hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
902
903 if (msg->msg_flags&MSG_CONFIRM)
904 goto do_confirm;
905
906 back_from_confirm:
907 if (hdrincl)
908 err = rawv6_send_hdrinc(sk, msg, len, &fl6, &dst,
909 msg->msg_flags, &ipc6.sockc);
910 else {
911 ipc6.opt = opt;
912 lock_sock(sk);
913 err = ip6_append_data(sk, raw6_getfrag, &rfv,
914 len, 0, &ipc6, &fl6, dst_rt6_info(dst),
915 msg->msg_flags);
916
917 if (err)
918 ip6_flush_pending_frames(sk);
919 else if (!(msg->msg_flags & MSG_MORE))
920 err = rawv6_push_pending_frames(sk, &fl6, rp);
921 release_sock(sk);
922 }
923 done:
924 dst_release(dst);
925 out:
926 fl6_sock_release(flowlabel);
927 txopt_put(opt_to_free);
928 return err < 0 ? err : len;
929 do_confirm:
930 if (msg->msg_flags & MSG_PROBE)
931 dst_confirm_neigh(dst, &fl6.daddr);
932 if (!(msg->msg_flags & MSG_PROBE) || len)
933 goto back_from_confirm;
934 err = 0;
935 goto done;
936 }
937
rawv6_seticmpfilter(struct sock * sk,int optname,sockptr_t optval,int optlen)938 static int rawv6_seticmpfilter(struct sock *sk, int optname,
939 sockptr_t optval, int optlen)
940 {
941 switch (optname) {
942 case ICMPV6_FILTER:
943 if (optlen > sizeof(struct icmp6_filter))
944 optlen = sizeof(struct icmp6_filter);
945 if (copy_from_sockptr(&raw6_sk(sk)->filter, optval, optlen))
946 return -EFAULT;
947 return 0;
948 default:
949 return -ENOPROTOOPT;
950 }
951
952 return 0;
953 }
954
rawv6_geticmpfilter(struct sock * sk,int optname,char __user * optval,int __user * optlen)955 static int rawv6_geticmpfilter(struct sock *sk, int optname,
956 char __user *optval, int __user *optlen)
957 {
958 int len;
959
960 switch (optname) {
961 case ICMPV6_FILTER:
962 if (get_user(len, optlen))
963 return -EFAULT;
964 if (len < 0)
965 return -EINVAL;
966 if (len > sizeof(struct icmp6_filter))
967 len = sizeof(struct icmp6_filter);
968 if (put_user(len, optlen))
969 return -EFAULT;
970 if (copy_to_user(optval, &raw6_sk(sk)->filter, len))
971 return -EFAULT;
972 return 0;
973 default:
974 return -ENOPROTOOPT;
975 }
976
977 return 0;
978 }
979
980
do_rawv6_setsockopt(struct sock * sk,int level,int optname,sockptr_t optval,unsigned int optlen)981 static int do_rawv6_setsockopt(struct sock *sk, int level, int optname,
982 sockptr_t optval, unsigned int optlen)
983 {
984 struct raw6_sock *rp = raw6_sk(sk);
985 int val;
986
987 if (optlen < sizeof(val))
988 return -EINVAL;
989
990 if (copy_from_sockptr(&val, optval, sizeof(val)))
991 return -EFAULT;
992
993 switch (optname) {
994 case IPV6_HDRINCL:
995 if (sk->sk_type != SOCK_RAW)
996 return -EINVAL;
997 inet_assign_bit(HDRINCL, sk, val);
998 return 0;
999 case IPV6_CHECKSUM:
1000 if (inet_sk(sk)->inet_num == IPPROTO_ICMPV6 &&
1001 level == IPPROTO_IPV6) {
1002 /*
1003 * RFC3542 tells that IPV6_CHECKSUM socket
1004 * option in the IPPROTO_IPV6 level is not
1005 * allowed on ICMPv6 sockets.
1006 * If you want to set it, use IPPROTO_RAW
1007 * level IPV6_CHECKSUM socket option
1008 * (Linux extension).
1009 */
1010 return -EINVAL;
1011 }
1012
1013 /* You may get strange result with a positive odd offset;
1014 RFC2292bis agrees with me. */
1015 if (val > 0 && (val&1))
1016 return -EINVAL;
1017 if (val < 0) {
1018 rp->checksum = 0;
1019 } else {
1020 rp->checksum = 1;
1021 rp->offset = val;
1022 }
1023
1024 return 0;
1025
1026 default:
1027 return -ENOPROTOOPT;
1028 }
1029 }
1030
rawv6_setsockopt(struct sock * sk,int level,int optname,sockptr_t optval,unsigned int optlen)1031 static int rawv6_setsockopt(struct sock *sk, int level, int optname,
1032 sockptr_t optval, unsigned int optlen)
1033 {
1034 switch (level) {
1035 case SOL_RAW:
1036 break;
1037
1038 case SOL_ICMPV6:
1039 if (inet_sk(sk)->inet_num != IPPROTO_ICMPV6)
1040 return -EOPNOTSUPP;
1041 return rawv6_seticmpfilter(sk, optname, optval, optlen);
1042 case SOL_IPV6:
1043 if (optname == IPV6_CHECKSUM ||
1044 optname == IPV6_HDRINCL)
1045 break;
1046 fallthrough;
1047 default:
1048 return ipv6_setsockopt(sk, level, optname, optval, optlen);
1049 }
1050
1051 return do_rawv6_setsockopt(sk, level, optname, optval, optlen);
1052 }
1053
do_rawv6_getsockopt(struct sock * sk,int optname,sockopt_t * opt)1054 static int do_rawv6_getsockopt(struct sock *sk, int optname, sockopt_t *opt)
1055 {
1056 struct raw6_sock *rp = raw6_sk(sk);
1057 int val, len;
1058
1059 len = opt->optlen;
1060
1061 switch (optname) {
1062 case IPV6_HDRINCL:
1063 val = inet_test_bit(HDRINCL, sk);
1064 break;
1065 case IPV6_CHECKSUM:
1066 /*
1067 * We allow getsockopt() for IPPROTO_IPV6-level
1068 * IPV6_CHECKSUM socket option on ICMPv6 sockets
1069 * since RFC3542 is silent about it.
1070 */
1071 if (rp->checksum == 0)
1072 val = -1;
1073 else
1074 val = rp->offset;
1075 break;
1076
1077 default:
1078 return -ENOPROTOOPT;
1079 }
1080
1081 len = umin(sizeof(int), len);
1082
1083 opt->optlen = len;
1084 if (copy_to_iter(&val, len, &opt->iter_out) != len)
1085 return -EFAULT;
1086 return 0;
1087 }
1088
rawv6_getsockopt(struct sock * sk,int level,int optname,char __user * optval,int __user * optlen)1089 static int rawv6_getsockopt(struct sock *sk, int level, int optname,
1090 char __user *optval, int __user *optlen)
1091 {
1092 sockopt_t opt;
1093 int err;
1094
1095 switch (level) {
1096 case SOL_RAW:
1097 break;
1098
1099 case SOL_ICMPV6:
1100 if (inet_sk(sk)->inet_num != IPPROTO_ICMPV6)
1101 return -EOPNOTSUPP;
1102 return rawv6_geticmpfilter(sk, optname, optval, optlen);
1103 case SOL_IPV6:
1104 if (optname == IPV6_CHECKSUM ||
1105 optname == IPV6_HDRINCL)
1106 break;
1107 fallthrough;
1108 default:
1109 return ipv6_getsockopt(sk, level, optname, optval, optlen);
1110 }
1111
1112 err = sockopt_init_user(&opt, optval, optlen);
1113 if (err)
1114 return err;
1115
1116 err = do_rawv6_getsockopt(sk, optname, &opt);
1117 if (err)
1118 return err;
1119
1120 if (put_user(opt.optlen, optlen))
1121 return -EFAULT;
1122
1123 return 0;
1124 }
1125
rawv6_ioctl(struct sock * sk,int cmd,int * karg)1126 static int rawv6_ioctl(struct sock *sk, int cmd, int *karg)
1127 {
1128 switch (cmd) {
1129 case SIOCOUTQ: {
1130 *karg = sk_wmem_alloc_get(sk);
1131 return 0;
1132 }
1133 case SIOCINQ: {
1134 struct sk_buff *skb;
1135
1136 spin_lock_bh(&sk->sk_receive_queue.lock);
1137 skb = skb_peek(&sk->sk_receive_queue);
1138 if (skb)
1139 *karg = skb->len;
1140 else
1141 *karg = 0;
1142 spin_unlock_bh(&sk->sk_receive_queue.lock);
1143 return 0;
1144 }
1145
1146 default:
1147 #ifdef CONFIG_IPV6_MROUTE
1148 return ip6mr_ioctl(sk, cmd, karg);
1149 #else
1150 return -ENOIOCTLCMD;
1151 #endif
1152 }
1153 }
1154
1155 #ifdef CONFIG_COMPAT
compat_rawv6_ioctl(struct sock * sk,unsigned int cmd,unsigned long arg)1156 static int compat_rawv6_ioctl(struct sock *sk, unsigned int cmd, unsigned long arg)
1157 {
1158 switch (cmd) {
1159 case SIOCOUTQ:
1160 case SIOCINQ:
1161 return -ENOIOCTLCMD;
1162 default:
1163 #ifdef CONFIG_IPV6_MROUTE
1164 return ip6mr_compat_ioctl(sk, cmd, compat_ptr(arg));
1165 #else
1166 return -ENOIOCTLCMD;
1167 #endif
1168 }
1169 }
1170 #endif
1171
rawv6_close(struct sock * sk,long timeout)1172 static void rawv6_close(struct sock *sk, long timeout)
1173 {
1174 if (inet_sk(sk)->inet_num == IPPROTO_RAW)
1175 ip6_ra_control(sk, -1);
1176 ip6mr_sk_done(sk);
1177 sk_common_release(sk);
1178 }
1179
raw6_destroy(struct sock * sk)1180 static void raw6_destroy(struct sock *sk)
1181 {
1182 lock_sock(sk);
1183 ip6_flush_pending_frames(sk);
1184 release_sock(sk);
1185 }
1186
rawv6_init_sk(struct sock * sk)1187 static int rawv6_init_sk(struct sock *sk)
1188 {
1189 struct raw6_sock *rp = raw6_sk(sk);
1190
1191 sk->sk_drop_counters = &rp->drop_counters;
1192 switch (inet_sk(sk)->inet_num) {
1193 case IPPROTO_ICMPV6:
1194 rp->checksum = 1;
1195 rp->offset = 2;
1196 break;
1197 case IPPROTO_MH:
1198 rp->checksum = 1;
1199 rp->offset = 4;
1200 break;
1201 default:
1202 break;
1203 }
1204 return 0;
1205 }
1206
1207 struct proto rawv6_prot = {
1208 .name = "RAWv6",
1209 .owner = THIS_MODULE,
1210 .close = rawv6_close,
1211 .destroy = raw6_destroy,
1212 .connect = ip6_datagram_connect_v6_only,
1213 .disconnect = __udp_disconnect,
1214 .ioctl = rawv6_ioctl,
1215 .init = rawv6_init_sk,
1216 .setsockopt = rawv6_setsockopt,
1217 .getsockopt = rawv6_getsockopt,
1218 .sendmsg = rawv6_sendmsg,
1219 .recvmsg = rawv6_recvmsg,
1220 .bind = rawv6_bind,
1221 .backlog_rcv = rawv6_rcv_skb,
1222 .hash = raw_hash_sk,
1223 .unhash = raw_unhash_sk,
1224 .obj_size = sizeof(struct raw6_sock),
1225 .ipv6_pinfo_offset = offsetof(struct raw6_sock, inet6),
1226 .useroffset = offsetof(struct raw6_sock, filter),
1227 .usersize = sizeof_field(struct raw6_sock, filter),
1228 .h.raw_hash = &raw_v6_hashinfo,
1229 #ifdef CONFIG_COMPAT
1230 .compat_ioctl = compat_rawv6_ioctl,
1231 #endif
1232 .diag_destroy = raw_abort,
1233 };
1234
1235 #ifdef CONFIG_PROC_FS
raw6_seq_show(struct seq_file * seq,void * v)1236 static int raw6_seq_show(struct seq_file *seq, void *v)
1237 {
1238 if (v == SEQ_START_TOKEN) {
1239 seq_puts(seq, IPV6_SEQ_DGRAM_HEADER);
1240 } else {
1241 struct sock *sp = v;
1242 __u16 srcp = inet_sk(sp)->inet_num;
1243 ip6_dgram_sock_seq_show(seq, v, srcp, 0,
1244 raw_seq_private(seq)->bucket);
1245 }
1246 return 0;
1247 }
1248
1249 static const struct seq_operations raw6_seq_ops = {
1250 .start = raw_seq_start,
1251 .next = raw_seq_next,
1252 .stop = raw_seq_stop,
1253 .show = raw6_seq_show,
1254 };
1255
raw6_init_net(struct net * net)1256 static int __net_init raw6_init_net(struct net *net)
1257 {
1258 if (!proc_create_net_data("raw6", 0444, net->proc_net, &raw6_seq_ops,
1259 sizeof(struct raw_iter_state), &raw_v6_hashinfo))
1260 return -ENOMEM;
1261
1262 return 0;
1263 }
1264
raw6_exit_net(struct net * net)1265 static void __net_exit raw6_exit_net(struct net *net)
1266 {
1267 remove_proc_entry("raw6", net->proc_net);
1268 }
1269
1270 static struct pernet_operations raw6_net_ops = {
1271 .init = raw6_init_net,
1272 .exit = raw6_exit_net,
1273 };
1274
raw6_proc_init(void)1275 int __init raw6_proc_init(void)
1276 {
1277 return register_pernet_subsys(&raw6_net_ops);
1278 }
1279
raw6_proc_exit(void)1280 void raw6_proc_exit(void)
1281 {
1282 unregister_pernet_subsys(&raw6_net_ops);
1283 }
1284 #endif /* CONFIG_PROC_FS */
1285
1286 /* Same as inet6_dgram_ops, sans udp_poll. */
1287 const struct proto_ops inet6_sockraw_ops = {
1288 .family = PF_INET6,
1289 .owner = THIS_MODULE,
1290 .release = inet6_release,
1291 .bind = inet6_bind,
1292 .connect = inet_dgram_connect, /* ok */
1293 .socketpair = sock_no_socketpair, /* a do nothing */
1294 .accept = sock_no_accept, /* a do nothing */
1295 .getname = inet6_getname,
1296 .poll = datagram_poll, /* ok */
1297 .ioctl = inet6_ioctl, /* must change */
1298 .gettstamp = sock_gettstamp,
1299 .listen = sock_no_listen, /* ok */
1300 .shutdown = inet_shutdown, /* ok */
1301 .setsockopt = sock_common_setsockopt, /* ok */
1302 .getsockopt = sock_common_getsockopt, /* ok */
1303 .sendmsg = inet_sendmsg, /* ok */
1304 .recvmsg = sock_common_recvmsg, /* ok */
1305 .mmap = sock_no_mmap,
1306 #ifdef CONFIG_COMPAT
1307 .compat_ioctl = inet6_compat_ioctl,
1308 #endif
1309 };
1310
1311 static struct inet_protosw rawv6_protosw = {
1312 .type = SOCK_RAW,
1313 .protocol = IPPROTO_IP, /* wild card */
1314 .prot = &rawv6_prot,
1315 .ops = &inet6_sockraw_ops,
1316 .flags = INET_PROTOSW_REUSE,
1317 };
1318
rawv6_init(void)1319 int __init rawv6_init(void)
1320 {
1321 return inet6_register_protosw(&rawv6_protosw);
1322 }
1323
rawv6_exit(void)1324 void rawv6_exit(void)
1325 {
1326 inet6_unregister_protosw(&rawv6_protosw);
1327 }
1328