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1/*
2 * INET An implementation of the TCP/IP protocol suite for the LINUX
3 * operating system. INET is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
5 *
6 * The IP to API glue.
7 *
8 * Authors: see ip.c
9 *
10 * Fixes:
11 * Many : Split from ip.c , see ip.c for history.
12 * Martin Mares : TOS setting fixed.
13 * Alan Cox : Fixed a couple of oopses in Martin's
14 * TOS tweaks.
15 * Mike McLagan : Routing by source
16 */
17
18#include <linux/module.h>
19#include <linux/types.h>
20#include <linux/mm.h>
21#include <linux/skbuff.h>
22#include <linux/ip.h>
23#include <linux/icmp.h>
24#include <linux/inetdevice.h>
25#include <linux/netdevice.h>
26#include <linux/slab.h>
27#include <net/sock.h>
28#include <net/ip.h>
29#include <net/icmp.h>
30#include <net/tcp_states.h>
31#include <linux/udp.h>
32#include <linux/igmp.h>
33#include <linux/netfilter.h>
34#include <linux/route.h>
35#include <linux/mroute.h>
36#include <net/inet_ecn.h>
37#include <net/route.h>
38#include <net/xfrm.h>
39#include <net/compat.h>
40#include <net/checksum.h>
41#if IS_ENABLED(CONFIG_IPV6)
42#include <net/transp_v6.h>
43#endif
44#include <net/ip_fib.h>
45
46#include <linux/errqueue.h>
47#include <asm/uaccess.h>
48
49/*
50 * SOL_IP control messages.
51 */
52
53static void ip_cmsg_recv_pktinfo(struct msghdr *msg, struct sk_buff *skb)
54{
55 struct in_pktinfo info = *PKTINFO_SKB_CB(skb);
56
57 info.ipi_addr.s_addr = ip_hdr(skb)->daddr;
58
59 put_cmsg(msg, SOL_IP, IP_PKTINFO, sizeof(info), &info);
60}
61
62static void ip_cmsg_recv_ttl(struct msghdr *msg, struct sk_buff *skb)
63{
64 int ttl = ip_hdr(skb)->ttl;
65 put_cmsg(msg, SOL_IP, IP_TTL, sizeof(int), &ttl);
66}
67
68static void ip_cmsg_recv_tos(struct msghdr *msg, struct sk_buff *skb)
69{
70 put_cmsg(msg, SOL_IP, IP_TOS, 1, &ip_hdr(skb)->tos);
71}
72
73static void ip_cmsg_recv_opts(struct msghdr *msg, struct sk_buff *skb)
74{
75 if (IPCB(skb)->opt.optlen == 0)
76 return;
77
78 put_cmsg(msg, SOL_IP, IP_RECVOPTS, IPCB(skb)->opt.optlen,
79 ip_hdr(skb) + 1);
80}
81
82
83static void ip_cmsg_recv_retopts(struct msghdr *msg, struct sk_buff *skb)
84{
85 unsigned char optbuf[sizeof(struct ip_options) + 40];
86 struct ip_options *opt = (struct ip_options *)optbuf;
87
88 if (IPCB(skb)->opt.optlen == 0)
89 return;
90
91 if (ip_options_echo(opt, skb)) {
92 msg->msg_flags |= MSG_CTRUNC;
93 return;
94 }
95 ip_options_undo(opt);
96
97 put_cmsg(msg, SOL_IP, IP_RETOPTS, opt->optlen, opt->__data);
98}
99
100static void ip_cmsg_recv_checksum(struct msghdr *msg, struct sk_buff *skb,
101 int offset)
102{
103 __wsum csum = skb->csum;
104
105 if (skb->ip_summed != CHECKSUM_COMPLETE)
106 return;
107
108 if (offset != 0)
109 csum = csum_sub(csum, csum_partial(skb->data, offset, 0));
110
111 put_cmsg(msg, SOL_IP, IP_CHECKSUM, sizeof(__wsum), &csum);
112}
113
114static void ip_cmsg_recv_security(struct msghdr *msg, struct sk_buff *skb)
115{
116 char *secdata;
117 u32 seclen, secid;
118 int err;
119
120 err = security_socket_getpeersec_dgram(NULL, skb, &secid);
121 if (err)
122 return;
123
124 err = security_secid_to_secctx(secid, &secdata, &seclen);
125 if (err)
126 return;
127
128 put_cmsg(msg, SOL_IP, SCM_SECURITY, seclen, secdata);
129 security_release_secctx(secdata, seclen);
130}
131
132static void ip_cmsg_recv_dstaddr(struct msghdr *msg, struct sk_buff *skb)
133{
134 struct sockaddr_in sin;
135 const struct iphdr *iph = ip_hdr(skb);
136 __be16 *ports = (__be16 *)skb_transport_header(skb);
137
138 if (skb_transport_offset(skb) + 4 > skb->len)
139 return;
140
141 /* All current transport protocols have the port numbers in the
142 * first four bytes of the transport header and this function is
143 * written with this assumption in mind.
144 */
145
146 sin.sin_family = AF_INET;
147 sin.sin_addr.s_addr = iph->daddr;
148 sin.sin_port = ports[1];
149 memset(sin.sin_zero, 0, sizeof(sin.sin_zero));
150
151 put_cmsg(msg, SOL_IP, IP_ORIGDSTADDR, sizeof(sin), &sin);
152}
153
154void ip_cmsg_recv_offset(struct msghdr *msg, struct sk_buff *skb,
155 int offset)
156{
157 struct inet_sock *inet = inet_sk(skb->sk);
158 unsigned int flags = inet->cmsg_flags;
159
160 /* Ordered by supposed usage frequency */
161 if (flags & IP_CMSG_PKTINFO) {
162 ip_cmsg_recv_pktinfo(msg, skb);
163
164 flags &= ~IP_CMSG_PKTINFO;
165 if (!flags)
166 return;
167 }
168
169 if (flags & IP_CMSG_TTL) {
170 ip_cmsg_recv_ttl(msg, skb);
171
172 flags &= ~IP_CMSG_TTL;
173 if (!flags)
174 return;
175 }
176
177 if (flags & IP_CMSG_TOS) {
178 ip_cmsg_recv_tos(msg, skb);
179
180 flags &= ~IP_CMSG_TOS;
181 if (!flags)
182 return;
183 }
184
185 if (flags & IP_CMSG_RECVOPTS) {
186 ip_cmsg_recv_opts(msg, skb);
187
188 flags &= ~IP_CMSG_RECVOPTS;
189 if (!flags)
190 return;
191 }
192
193 if (flags & IP_CMSG_RETOPTS) {
194 ip_cmsg_recv_retopts(msg, skb);
195
196 flags &= ~IP_CMSG_RETOPTS;
197 if (!flags)
198 return;
199 }
200
201 if (flags & IP_CMSG_PASSSEC) {
202 ip_cmsg_recv_security(msg, skb);
203
204 flags &= ~IP_CMSG_PASSSEC;
205 if (!flags)
206 return;
207 }
208
209 if (flags & IP_CMSG_ORIGDSTADDR) {
210 ip_cmsg_recv_dstaddr(msg, skb);
211
212 flags &= ~IP_CMSG_ORIGDSTADDR;
213 if (!flags)
214 return;
215 }
216
217 if (flags & IP_CMSG_CHECKSUM)
218 ip_cmsg_recv_checksum(msg, skb, offset);
219}
220EXPORT_SYMBOL(ip_cmsg_recv_offset);
221
222int ip_cmsg_send(struct net *net, struct msghdr *msg, struct ipcm_cookie *ipc,
223 bool allow_ipv6)
224{
225 int err, val;
226 struct cmsghdr *cmsg;
227
228 for_each_cmsghdr(cmsg, msg) {
229 if (!CMSG_OK(msg, cmsg))
230 return -EINVAL;
231#if IS_ENABLED(CONFIG_IPV6)
232 if (allow_ipv6 &&
233 cmsg->cmsg_level == SOL_IPV6 &&
234 cmsg->cmsg_type == IPV6_PKTINFO) {
235 struct in6_pktinfo *src_info;
236
237 if (cmsg->cmsg_len < CMSG_LEN(sizeof(*src_info)))
238 return -EINVAL;
239 src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg);
240 if (!ipv6_addr_v4mapped(&src_info->ipi6_addr))
241 return -EINVAL;
242 ipc->oif = src_info->ipi6_ifindex;
243 ipc->addr = src_info->ipi6_addr.s6_addr32[3];
244 continue;
245 }
246#endif
247 if (cmsg->cmsg_level != SOL_IP)
248 continue;
249 switch (cmsg->cmsg_type) {
250 case IP_RETOPTS:
251 err = cmsg->cmsg_len - CMSG_ALIGN(sizeof(struct cmsghdr));
252
253 /* Our caller is responsible for freeing ipc->opt */
254 err = ip_options_get(net, &ipc->opt, CMSG_DATA(cmsg),
255 err < 40 ? err : 40);
256 if (err)
257 return err;
258 break;
259 case IP_PKTINFO:
260 {
261 struct in_pktinfo *info;
262 if (cmsg->cmsg_len != CMSG_LEN(sizeof(struct in_pktinfo)))
263 return -EINVAL;
264 info = (struct in_pktinfo *)CMSG_DATA(cmsg);
265 ipc->oif = info->ipi_ifindex;
266 ipc->addr = info->ipi_spec_dst.s_addr;
267 break;
268 }
269 case IP_TTL:
270 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
271 return -EINVAL;
272 val = *(int *)CMSG_DATA(cmsg);
273 if (val < 1 || val > 255)
274 return -EINVAL;
275 ipc->ttl = val;
276 break;
277 case IP_TOS:
278 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
279 return -EINVAL;
280 val = *(int *)CMSG_DATA(cmsg);
281 if (val < 0 || val > 255)
282 return -EINVAL;
283 ipc->tos = val;
284 ipc->priority = rt_tos2priority(ipc->tos);
285 break;
286
287 default:
288 return -EINVAL;
289 }
290 }
291 return 0;
292}
293
294
295/* Special input handler for packets caught by router alert option.
296 They are selected only by protocol field, and then processed likely
297 local ones; but only if someone wants them! Otherwise, router
298 not running rsvpd will kill RSVP.
299
300 It is user level problem, what it will make with them.
301 I have no idea, how it will masquearde or NAT them (it is joke, joke :-)),
302 but receiver should be enough clever f.e. to forward mtrace requests,
303 sent to multicast group to reach destination designated router.
304 */
305struct ip_ra_chain __rcu *ip_ra_chain;
306static DEFINE_SPINLOCK(ip_ra_lock);
307
308
309static void ip_ra_destroy_rcu(struct rcu_head *head)
310{
311 struct ip_ra_chain *ra = container_of(head, struct ip_ra_chain, rcu);
312
313 sock_put(ra->saved_sk);
314 kfree(ra);
315}
316
317int ip_ra_control(struct sock *sk, unsigned char on,
318 void (*destructor)(struct sock *))
319{
320 struct ip_ra_chain *ra, *new_ra;
321 struct ip_ra_chain __rcu **rap;
322
323 if (sk->sk_type != SOCK_RAW || inet_sk(sk)->inet_num == IPPROTO_RAW)
324 return -EINVAL;
325
326 new_ra = on ? kmalloc(sizeof(*new_ra), GFP_KERNEL) : NULL;
327
328 spin_lock_bh(&ip_ra_lock);
329 for (rap = &ip_ra_chain;
330 (ra = rcu_dereference_protected(*rap,
331 lockdep_is_held(&ip_ra_lock))) != NULL;
332 rap = &ra->next) {
333 if (ra->sk == sk) {
334 if (on) {
335 spin_unlock_bh(&ip_ra_lock);
336 kfree(new_ra);
337 return -EADDRINUSE;
338 }
339 /* dont let ip_call_ra_chain() use sk again */
340 ra->sk = NULL;
341 RCU_INIT_POINTER(*rap, ra->next);
342 spin_unlock_bh(&ip_ra_lock);
343
344 if (ra->destructor)
345 ra->destructor(sk);
346 /*
347 * Delay sock_put(sk) and kfree(ra) after one rcu grace
348 * period. This guarantee ip_call_ra_chain() dont need
349 * to mess with socket refcounts.
350 */
351 ra->saved_sk = sk;
352 call_rcu(&ra->rcu, ip_ra_destroy_rcu);
353 return 0;
354 }
355 }
356 if (!new_ra) {
357 spin_unlock_bh(&ip_ra_lock);
358 return -ENOBUFS;
359 }
360 new_ra->sk = sk;
361 new_ra->destructor = destructor;
362
363 RCU_INIT_POINTER(new_ra->next, ra);
364 rcu_assign_pointer(*rap, new_ra);
365 sock_hold(sk);
366 spin_unlock_bh(&ip_ra_lock);
367
368 return 0;
369}
370
371void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
372 __be16 port, u32 info, u8 *payload)
373{
374 struct sock_exterr_skb *serr;
375
376 skb = skb_clone(skb, GFP_ATOMIC);
377 if (!skb)
378 return;
379
380 serr = SKB_EXT_ERR(skb);
381 serr->ee.ee_errno = err;
382 serr->ee.ee_origin = SO_EE_ORIGIN_ICMP;
383 serr->ee.ee_type = icmp_hdr(skb)->type;
384 serr->ee.ee_code = icmp_hdr(skb)->code;
385 serr->ee.ee_pad = 0;
386 serr->ee.ee_info = info;
387 serr->ee.ee_data = 0;
388 serr->addr_offset = (u8 *)&(((struct iphdr *)(icmp_hdr(skb) + 1))->daddr) -
389 skb_network_header(skb);
390 serr->port = port;
391
392 if (skb_pull(skb, payload - skb->data)) {
393 skb_reset_transport_header(skb);
394 if (sock_queue_err_skb(sk, skb) == 0)
395 return;
396 }
397 kfree_skb(skb);
398}
399
400void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 port, u32 info)
401{
402 struct inet_sock *inet = inet_sk(sk);
403 struct sock_exterr_skb *serr;
404 struct iphdr *iph;
405 struct sk_buff *skb;
406
407 if (!inet->recverr)
408 return;
409
410 skb = alloc_skb(sizeof(struct iphdr), GFP_ATOMIC);
411 if (!skb)
412 return;
413
414 skb_put(skb, sizeof(struct iphdr));
415 skb_reset_network_header(skb);
416 iph = ip_hdr(skb);
417 iph->daddr = daddr;
418
419 serr = SKB_EXT_ERR(skb);
420 serr->ee.ee_errno = err;
421 serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
422 serr->ee.ee_type = 0;
423 serr->ee.ee_code = 0;
424 serr->ee.ee_pad = 0;
425 serr->ee.ee_info = info;
426 serr->ee.ee_data = 0;
427 serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
428 serr->port = port;
429
430 __skb_pull(skb, skb_tail_pointer(skb) - skb->data);
431 skb_reset_transport_header(skb);
432
433 if (sock_queue_err_skb(sk, skb))
434 kfree_skb(skb);
435}
436
437/* For some errors we have valid addr_offset even with zero payload and
438 * zero port. Also, addr_offset should be supported if port is set.
439 */
440static inline bool ipv4_datagram_support_addr(struct sock_exterr_skb *serr)
441{
442 return serr->ee.ee_origin == SO_EE_ORIGIN_ICMP ||
443 serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL || serr->port;
444}
445
446/* IPv4 supports cmsg on all imcp errors and some timestamps
447 *
448 * Timestamp code paths do not initialize the fields expected by cmsg:
449 * the PKTINFO fields in skb->cb[]. Fill those in here.
450 */
451static bool ipv4_datagram_support_cmsg(const struct sock *sk,
452 struct sk_buff *skb,
453 int ee_origin)
454{
455 struct in_pktinfo *info;
456
457 if (ee_origin == SO_EE_ORIGIN_ICMP)
458 return true;
459
460 if (ee_origin == SO_EE_ORIGIN_LOCAL)
461 return false;
462
463 /* Support IP_PKTINFO on tstamp packets if requested, to correlate
464 * timestamp with egress dev. Not possible for packets without dev
465 * or without payload (SOF_TIMESTAMPING_OPT_TSONLY).
466 */
467 if ((!(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_CMSG)) ||
468 (!skb->dev))
469 return false;
470
471 info = PKTINFO_SKB_CB(skb);
472 info->ipi_spec_dst.s_addr = ip_hdr(skb)->saddr;
473 info->ipi_ifindex = skb->dev->ifindex;
474 return true;
475}
476
477/*
478 * Handle MSG_ERRQUEUE
479 */
480int ip_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
481{
482 struct sock_exterr_skb *serr;
483 struct sk_buff *skb;
484 DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name);
485 struct {
486 struct sock_extended_err ee;
487 struct sockaddr_in offender;
488 } errhdr;
489 int err;
490 int copied;
491
492 WARN_ON_ONCE(sk->sk_family == AF_INET6);
493
494 err = -EAGAIN;
495 skb = sock_dequeue_err_skb(sk);
496 if (!skb)
497 goto out;
498
499 copied = skb->len;
500 if (copied > len) {
501 msg->msg_flags |= MSG_TRUNC;
502 copied = len;
503 }
504 err = skb_copy_datagram_msg(skb, 0, msg, copied);
505 if (err)
506 goto out_free_skb;
507
508 sock_recv_timestamp(msg, sk, skb);
509
510 serr = SKB_EXT_ERR(skb);
511
512 if (sin && ipv4_datagram_support_addr(serr)) {
513 sin->sin_family = AF_INET;
514 sin->sin_addr.s_addr = *(__be32 *)(skb_network_header(skb) +
515 serr->addr_offset);
516 sin->sin_port = serr->port;
517 memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
518 *addr_len = sizeof(*sin);
519 }
520
521 memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
522 sin = &errhdr.offender;
523 memset(sin, 0, sizeof(*sin));
524
525 if (ipv4_datagram_support_cmsg(sk, skb, serr->ee.ee_origin)) {
526 sin->sin_family = AF_INET;
527 sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
528 if (inet_sk(sk)->cmsg_flags)
529 ip_cmsg_recv(msg, skb);
530 }
531
532 put_cmsg(msg, SOL_IP, IP_RECVERR, sizeof(errhdr), &errhdr);
533
534 /* Now we could try to dump offended packet options */
535
536 msg->msg_flags |= MSG_ERRQUEUE;
537 err = copied;
538
539out_free_skb:
540 kfree_skb(skb);
541out:
542 return err;
543}
544
545
546/*
547 * Socket option code for IP. This is the end of the line after any
548 * TCP,UDP etc options on an IP socket.
549 */
550static bool setsockopt_needs_rtnl(int optname)
551{
552 switch (optname) {
553 case IP_ADD_MEMBERSHIP:
554 case IP_ADD_SOURCE_MEMBERSHIP:
555 case IP_BLOCK_SOURCE:
556 case IP_DROP_MEMBERSHIP:
557 case IP_DROP_SOURCE_MEMBERSHIP:
558 case IP_MSFILTER:
559 case IP_UNBLOCK_SOURCE:
560 case MCAST_BLOCK_SOURCE:
561 case MCAST_MSFILTER:
562 case MCAST_JOIN_GROUP:
563 case MCAST_JOIN_SOURCE_GROUP:
564 case MCAST_LEAVE_GROUP:
565 case MCAST_LEAVE_SOURCE_GROUP:
566 case MCAST_UNBLOCK_SOURCE:
567 return true;
568 }
569 return false;
570}
571
572static int do_ip_setsockopt(struct sock *sk, int level,
573 int optname, char __user *optval, unsigned int optlen)
574{
575 struct inet_sock *inet = inet_sk(sk);
576 struct net *net = sock_net(sk);
577 int val = 0, err;
578 bool needs_rtnl = setsockopt_needs_rtnl(optname);
579
580 switch (optname) {
581 case IP_PKTINFO:
582 case IP_RECVTTL:
583 case IP_RECVOPTS:
584 case IP_RECVTOS:
585 case IP_RETOPTS:
586 case IP_TOS:
587 case IP_TTL:
588 case IP_HDRINCL:
589 case IP_MTU_DISCOVER:
590 case IP_RECVERR:
591 case IP_ROUTER_ALERT:
592 case IP_FREEBIND:
593 case IP_PASSSEC:
594 case IP_TRANSPARENT:
595 case IP_MINTTL:
596 case IP_NODEFRAG:
597 case IP_BIND_ADDRESS_NO_PORT:
598 case IP_UNICAST_IF:
599 case IP_MULTICAST_TTL:
600 case IP_MULTICAST_ALL:
601 case IP_MULTICAST_LOOP:
602 case IP_RECVORIGDSTADDR:
603 case IP_CHECKSUM:
604 if (optlen >= sizeof(int)) {
605 if (get_user(val, (int __user *) optval))
606 return -EFAULT;
607 } else if (optlen >= sizeof(char)) {
608 unsigned char ucval;
609
610 if (get_user(ucval, (unsigned char __user *) optval))
611 return -EFAULT;
612 val = (int) ucval;
613 }
614 }
615
616 /* If optlen==0, it is equivalent to val == 0 */
617
618 if (ip_mroute_opt(optname))
619 return ip_mroute_setsockopt(sk, optname, optval, optlen);
620
621 err = 0;
622 if (needs_rtnl)
623 rtnl_lock();
624 lock_sock(sk);
625
626 switch (optname) {
627 case IP_OPTIONS:
628 {
629 struct ip_options_rcu *old, *opt = NULL;
630
631 if (optlen > 40)
632 goto e_inval;
633 err = ip_options_get_from_user(sock_net(sk), &opt,
634 optval, optlen);
635 if (err)
636 break;
637 old = rcu_dereference_protected(inet->inet_opt,
638 sock_owned_by_user(sk));
639 if (inet->is_icsk) {
640 struct inet_connection_sock *icsk = inet_csk(sk);
641#if IS_ENABLED(CONFIG_IPV6)
642 if (sk->sk_family == PF_INET ||
643 (!((1 << sk->sk_state) &
644 (TCPF_LISTEN | TCPF_CLOSE)) &&
645 inet->inet_daddr != LOOPBACK4_IPV6)) {
646#endif
647 if (old)
648 icsk->icsk_ext_hdr_len -= old->opt.optlen;
649 if (opt)
650 icsk->icsk_ext_hdr_len += opt->opt.optlen;
651 icsk->icsk_sync_mss(sk, icsk->icsk_pmtu_cookie);
652#if IS_ENABLED(CONFIG_IPV6)
653 }
654#endif
655 }
656 rcu_assign_pointer(inet->inet_opt, opt);
657 if (old)
658 kfree_rcu(old, rcu);
659 break;
660 }
661 case IP_PKTINFO:
662 if (val)
663 inet->cmsg_flags |= IP_CMSG_PKTINFO;
664 else
665 inet->cmsg_flags &= ~IP_CMSG_PKTINFO;
666 break;
667 case IP_RECVTTL:
668 if (val)
669 inet->cmsg_flags |= IP_CMSG_TTL;
670 else
671 inet->cmsg_flags &= ~IP_CMSG_TTL;
672 break;
673 case IP_RECVTOS:
674 if (val)
675 inet->cmsg_flags |= IP_CMSG_TOS;
676 else
677 inet->cmsg_flags &= ~IP_CMSG_TOS;
678 break;
679 case IP_RECVOPTS:
680 if (val)
681 inet->cmsg_flags |= IP_CMSG_RECVOPTS;
682 else
683 inet->cmsg_flags &= ~IP_CMSG_RECVOPTS;
684 break;
685 case IP_RETOPTS:
686 if (val)
687 inet->cmsg_flags |= IP_CMSG_RETOPTS;
688 else
689 inet->cmsg_flags &= ~IP_CMSG_RETOPTS;
690 break;
691 case IP_PASSSEC:
692 if (val)
693 inet->cmsg_flags |= IP_CMSG_PASSSEC;
694 else
695 inet->cmsg_flags &= ~IP_CMSG_PASSSEC;
696 break;
697 case IP_RECVORIGDSTADDR:
698 if (val)
699 inet->cmsg_flags |= IP_CMSG_ORIGDSTADDR;
700 else
701 inet->cmsg_flags &= ~IP_CMSG_ORIGDSTADDR;
702 break;
703 case IP_CHECKSUM:
704 if (val) {
705 if (!(inet->cmsg_flags & IP_CMSG_CHECKSUM)) {
706 inet_inc_convert_csum(sk);
707 inet->cmsg_flags |= IP_CMSG_CHECKSUM;
708 }
709 } else {
710 if (inet->cmsg_flags & IP_CMSG_CHECKSUM) {
711 inet_dec_convert_csum(sk);
712 inet->cmsg_flags &= ~IP_CMSG_CHECKSUM;
713 }
714 }
715 break;
716 case IP_TOS: /* This sets both TOS and Precedence */
717 if (sk->sk_type == SOCK_STREAM) {
718 val &= ~INET_ECN_MASK;
719 val |= inet->tos & INET_ECN_MASK;
720 }
721 if (inet->tos != val) {
722 inet->tos = val;
723 sk->sk_priority = rt_tos2priority(val);
724 sk_dst_reset(sk);
725 }
726 break;
727 case IP_TTL:
728 if (optlen < 1)
729 goto e_inval;
730 if (val != -1 && (val < 1 || val > 255))
731 goto e_inval;
732 inet->uc_ttl = val;
733 break;
734 case IP_HDRINCL:
735 if (sk->sk_type != SOCK_RAW) {
736 err = -ENOPROTOOPT;
737 break;
738 }
739 inet->hdrincl = val ? 1 : 0;
740 break;
741 case IP_NODEFRAG:
742 if (sk->sk_type != SOCK_RAW) {
743 err = -ENOPROTOOPT;
744 break;
745 }
746 inet->nodefrag = val ? 1 : 0;
747 break;
748 case IP_BIND_ADDRESS_NO_PORT:
749 inet->bind_address_no_port = val ? 1 : 0;
750 break;
751 case IP_MTU_DISCOVER:
752 if (val < IP_PMTUDISC_DONT || val > IP_PMTUDISC_OMIT)
753 goto e_inval;
754 inet->pmtudisc = val;
755 break;
756 case IP_RECVERR:
757 inet->recverr = !!val;
758 if (!val)
759 skb_queue_purge(&sk->sk_error_queue);
760 break;
761 case IP_MULTICAST_TTL:
762 if (sk->sk_type == SOCK_STREAM)
763 goto e_inval;
764 if (optlen < 1)
765 goto e_inval;
766 if (val == -1)
767 val = 1;
768 if (val < 0 || val > 255)
769 goto e_inval;
770 inet->mc_ttl = val;
771 break;
772 case IP_MULTICAST_LOOP:
773 if (optlen < 1)
774 goto e_inval;
775 inet->mc_loop = !!val;
776 break;
777 case IP_UNICAST_IF:
778 {
779 struct net_device *dev = NULL;
780 int ifindex;
781
782 if (optlen != sizeof(int))
783 goto e_inval;
784
785 ifindex = (__force int)ntohl((__force __be32)val);
786 if (ifindex == 0) {
787 inet->uc_index = 0;
788 err = 0;
789 break;
790 }
791
792 dev = dev_get_by_index(sock_net(sk), ifindex);
793 err = -EADDRNOTAVAIL;
794 if (!dev)
795 break;
796 dev_put(dev);
797
798 err = -EINVAL;
799 if (sk->sk_bound_dev_if)
800 break;
801
802 inet->uc_index = ifindex;
803 err = 0;
804 break;
805 }
806 case IP_MULTICAST_IF:
807 {
808 struct ip_mreqn mreq;
809 struct net_device *dev = NULL;
810
811 if (sk->sk_type == SOCK_STREAM)
812 goto e_inval;
813 /*
814 * Check the arguments are allowable
815 */
816
817 if (optlen < sizeof(struct in_addr))
818 goto e_inval;
819
820 err = -EFAULT;
821 if (optlen >= sizeof(struct ip_mreqn)) {
822 if (copy_from_user(&mreq, optval, sizeof(mreq)))
823 break;
824 } else {
825 memset(&mreq, 0, sizeof(mreq));
826 if (optlen >= sizeof(struct ip_mreq)) {
827 if (copy_from_user(&mreq, optval,
828 sizeof(struct ip_mreq)))
829 break;
830 } else if (optlen >= sizeof(struct in_addr)) {
831 if (copy_from_user(&mreq.imr_address, optval,
832 sizeof(struct in_addr)))
833 break;
834 }
835 }
836
837 if (!mreq.imr_ifindex) {
838 if (mreq.imr_address.s_addr == htonl(INADDR_ANY)) {
839 inet->mc_index = 0;
840 inet->mc_addr = 0;
841 err = 0;
842 break;
843 }
844 dev = ip_dev_find(sock_net(sk), mreq.imr_address.s_addr);
845 if (dev)
846 mreq.imr_ifindex = dev->ifindex;
847 } else
848 dev = dev_get_by_index(sock_net(sk), mreq.imr_ifindex);
849
850
851 err = -EADDRNOTAVAIL;
852 if (!dev)
853 break;
854 dev_put(dev);
855
856 err = -EINVAL;
857 if (sk->sk_bound_dev_if &&
858 mreq.imr_ifindex != sk->sk_bound_dev_if)
859 break;
860
861 inet->mc_index = mreq.imr_ifindex;
862 inet->mc_addr = mreq.imr_address.s_addr;
863 err = 0;
864 break;
865 }
866
867 case IP_ADD_MEMBERSHIP:
868 case IP_DROP_MEMBERSHIP:
869 {
870 struct ip_mreqn mreq;
871
872 err = -EPROTO;
873 if (inet_sk(sk)->is_icsk)
874 break;
875
876 if (optlen < sizeof(struct ip_mreq))
877 goto e_inval;
878 err = -EFAULT;
879 if (optlen >= sizeof(struct ip_mreqn)) {
880 if (copy_from_user(&mreq, optval, sizeof(mreq)))
881 break;
882 } else {
883 memset(&mreq, 0, sizeof(mreq));
884 if (copy_from_user(&mreq, optval, sizeof(struct ip_mreq)))
885 break;
886 }
887
888 if (optname == IP_ADD_MEMBERSHIP)
889 err = ip_mc_join_group(sk, &mreq);
890 else
891 err = ip_mc_leave_group(sk, &mreq);
892 break;
893 }
894 case IP_MSFILTER:
895 {
896 struct ip_msfilter *msf;
897
898 if (optlen < IP_MSFILTER_SIZE(0))
899 goto e_inval;
900 if (optlen > sysctl_optmem_max) {
901 err = -ENOBUFS;
902 break;
903 }
904 msf = kmalloc(optlen, GFP_KERNEL);
905 if (!msf) {
906 err = -ENOBUFS;
907 break;
908 }
909 err = -EFAULT;
910 if (copy_from_user(msf, optval, optlen)) {
911 kfree(msf);
912 break;
913 }
914 /* numsrc >= (1G-4) overflow in 32 bits */
915 if (msf->imsf_numsrc >= 0x3ffffffcU ||
916 msf->imsf_numsrc > net->ipv4.sysctl_igmp_max_msf) {
917 kfree(msf);
918 err = -ENOBUFS;
919 break;
920 }
921 if (IP_MSFILTER_SIZE(msf->imsf_numsrc) > optlen) {
922 kfree(msf);
923 err = -EINVAL;
924 break;
925 }
926 err = ip_mc_msfilter(sk, msf, 0);
927 kfree(msf);
928 break;
929 }
930 case IP_BLOCK_SOURCE:
931 case IP_UNBLOCK_SOURCE:
932 case IP_ADD_SOURCE_MEMBERSHIP:
933 case IP_DROP_SOURCE_MEMBERSHIP:
934 {
935 struct ip_mreq_source mreqs;
936 int omode, add;
937
938 if (optlen != sizeof(struct ip_mreq_source))
939 goto e_inval;
940 if (copy_from_user(&mreqs, optval, sizeof(mreqs))) {
941 err = -EFAULT;
942 break;
943 }
944 if (optname == IP_BLOCK_SOURCE) {
945 omode = MCAST_EXCLUDE;
946 add = 1;
947 } else if (optname == IP_UNBLOCK_SOURCE) {
948 omode = MCAST_EXCLUDE;
949 add = 0;
950 } else if (optname == IP_ADD_SOURCE_MEMBERSHIP) {
951 struct ip_mreqn mreq;
952
953 mreq.imr_multiaddr.s_addr = mreqs.imr_multiaddr;
954 mreq.imr_address.s_addr = mreqs.imr_interface;
955 mreq.imr_ifindex = 0;
956 err = ip_mc_join_group(sk, &mreq);
957 if (err && err != -EADDRINUSE)
958 break;
959 omode = MCAST_INCLUDE;
960 add = 1;
961 } else /* IP_DROP_SOURCE_MEMBERSHIP */ {
962 omode = MCAST_INCLUDE;
963 add = 0;
964 }
965 err = ip_mc_source(add, omode, sk, &mreqs, 0);
966 break;
967 }
968 case MCAST_JOIN_GROUP:
969 case MCAST_LEAVE_GROUP:
970 {
971 struct group_req greq;
972 struct sockaddr_in *psin;
973 struct ip_mreqn mreq;
974
975 if (optlen < sizeof(struct group_req))
976 goto e_inval;
977 err = -EFAULT;
978 if (copy_from_user(&greq, optval, sizeof(greq)))
979 break;
980 psin = (struct sockaddr_in *)&greq.gr_group;
981 if (psin->sin_family != AF_INET)
982 goto e_inval;
983 memset(&mreq, 0, sizeof(mreq));
984 mreq.imr_multiaddr = psin->sin_addr;
985 mreq.imr_ifindex = greq.gr_interface;
986
987 if (optname == MCAST_JOIN_GROUP)
988 err = ip_mc_join_group(sk, &mreq);
989 else
990 err = ip_mc_leave_group(sk, &mreq);
991 break;
992 }
993 case MCAST_JOIN_SOURCE_GROUP:
994 case MCAST_LEAVE_SOURCE_GROUP:
995 case MCAST_BLOCK_SOURCE:
996 case MCAST_UNBLOCK_SOURCE:
997 {
998 struct group_source_req greqs;
999 struct ip_mreq_source mreqs;
1000 struct sockaddr_in *psin;
1001 int omode, add;
1002
1003 if (optlen != sizeof(struct group_source_req))
1004 goto e_inval;
1005 if (copy_from_user(&greqs, optval, sizeof(greqs))) {
1006 err = -EFAULT;
1007 break;
1008 }
1009 if (greqs.gsr_group.ss_family != AF_INET ||
1010 greqs.gsr_source.ss_family != AF_INET) {
1011 err = -EADDRNOTAVAIL;
1012 break;
1013 }
1014 psin = (struct sockaddr_in *)&greqs.gsr_group;
1015 mreqs.imr_multiaddr = psin->sin_addr.s_addr;
1016 psin = (struct sockaddr_in *)&greqs.gsr_source;
1017 mreqs.imr_sourceaddr = psin->sin_addr.s_addr;
1018 mreqs.imr_interface = 0; /* use index for mc_source */
1019
1020 if (optname == MCAST_BLOCK_SOURCE) {
1021 omode = MCAST_EXCLUDE;
1022 add = 1;
1023 } else if (optname == MCAST_UNBLOCK_SOURCE) {
1024 omode = MCAST_EXCLUDE;
1025 add = 0;
1026 } else if (optname == MCAST_JOIN_SOURCE_GROUP) {
1027 struct ip_mreqn mreq;
1028
1029 psin = (struct sockaddr_in *)&greqs.gsr_group;
1030 mreq.imr_multiaddr = psin->sin_addr;
1031 mreq.imr_address.s_addr = 0;
1032 mreq.imr_ifindex = greqs.gsr_interface;
1033 err = ip_mc_join_group(sk, &mreq);
1034 if (err && err != -EADDRINUSE)
1035 break;
1036 greqs.gsr_interface = mreq.imr_ifindex;
1037 omode = MCAST_INCLUDE;
1038 add = 1;
1039 } else /* MCAST_LEAVE_SOURCE_GROUP */ {
1040 omode = MCAST_INCLUDE;
1041 add = 0;
1042 }
1043 err = ip_mc_source(add, omode, sk, &mreqs,
1044 greqs.gsr_interface);
1045 break;
1046 }
1047 case MCAST_MSFILTER:
1048 {
1049 struct sockaddr_in *psin;
1050 struct ip_msfilter *msf = NULL;
1051 struct group_filter *gsf = NULL;
1052 int msize, i, ifindex;
1053
1054 if (optlen < GROUP_FILTER_SIZE(0))
1055 goto e_inval;
1056 if (optlen > sysctl_optmem_max) {
1057 err = -ENOBUFS;
1058 break;
1059 }
1060 gsf = kmalloc(optlen, GFP_KERNEL);
1061 if (!gsf) {
1062 err = -ENOBUFS;
1063 break;
1064 }
1065 err = -EFAULT;
1066 if (copy_from_user(gsf, optval, optlen))
1067 goto mc_msf_out;
1068
1069 /* numsrc >= (4G-140)/128 overflow in 32 bits */
1070 if (gsf->gf_numsrc >= 0x1ffffff ||
1071 gsf->gf_numsrc > net->ipv4.sysctl_igmp_max_msf) {
1072 err = -ENOBUFS;
1073 goto mc_msf_out;
1074 }
1075 if (GROUP_FILTER_SIZE(gsf->gf_numsrc) > optlen) {
1076 err = -EINVAL;
1077 goto mc_msf_out;
1078 }
1079 msize = IP_MSFILTER_SIZE(gsf->gf_numsrc);
1080 msf = kmalloc(msize, GFP_KERNEL);
1081 if (!msf) {
1082 err = -ENOBUFS;
1083 goto mc_msf_out;
1084 }
1085 ifindex = gsf->gf_interface;
1086 psin = (struct sockaddr_in *)&gsf->gf_group;
1087 if (psin->sin_family != AF_INET) {
1088 err = -EADDRNOTAVAIL;
1089 goto mc_msf_out;
1090 }
1091 msf->imsf_multiaddr = psin->sin_addr.s_addr;
1092 msf->imsf_interface = 0;
1093 msf->imsf_fmode = gsf->gf_fmode;
1094 msf->imsf_numsrc = gsf->gf_numsrc;
1095 err = -EADDRNOTAVAIL;
1096 for (i = 0; i < gsf->gf_numsrc; ++i) {
1097 psin = (struct sockaddr_in *)&gsf->gf_slist[i];
1098
1099 if (psin->sin_family != AF_INET)
1100 goto mc_msf_out;
1101 msf->imsf_slist[i] = psin->sin_addr.s_addr;
1102 }
1103 kfree(gsf);
1104 gsf = NULL;
1105
1106 err = ip_mc_msfilter(sk, msf, ifindex);
1107mc_msf_out:
1108 kfree(msf);
1109 kfree(gsf);
1110 break;
1111 }
1112 case IP_MULTICAST_ALL:
1113 if (optlen < 1)
1114 goto e_inval;
1115 if (val != 0 && val != 1)
1116 goto e_inval;
1117 inet->mc_all = val;
1118 break;
1119 case IP_ROUTER_ALERT:
1120 err = ip_ra_control(sk, val ? 1 : 0, NULL);
1121 break;
1122
1123 case IP_FREEBIND:
1124 if (optlen < 1)
1125 goto e_inval;
1126 inet->freebind = !!val;
1127 break;
1128
1129 case IP_IPSEC_POLICY:
1130 case IP_XFRM_POLICY:
1131 err = -EPERM;
1132 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1133 break;
1134 err = xfrm_user_policy(sk, optname, optval, optlen);
1135 break;
1136
1137 case IP_TRANSPARENT:
1138 if (!!val && !ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
1139 !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1140 err = -EPERM;
1141 break;
1142 }
1143 if (optlen < 1)
1144 goto e_inval;
1145 inet->transparent = !!val;
1146 break;
1147
1148 case IP_MINTTL:
1149 if (optlen < 1)
1150 goto e_inval;
1151 if (val < 0 || val > 255)
1152 goto e_inval;
1153 inet->min_ttl = val;
1154 break;
1155
1156 default:
1157 err = -ENOPROTOOPT;
1158 break;
1159 }
1160 release_sock(sk);
1161 if (needs_rtnl)
1162 rtnl_unlock();
1163 return err;
1164
1165e_inval:
1166 release_sock(sk);
1167 if (needs_rtnl)
1168 rtnl_unlock();
1169 return -EINVAL;
1170}
1171
1172/**
1173 * ipv4_pktinfo_prepare - transfer some info from rtable to skb
1174 * @sk: socket
1175 * @skb: buffer
1176 *
1177 * To support IP_CMSG_PKTINFO option, we store rt_iif and specific
1178 * destination in skb->cb[] before dst drop.
1179 * This way, receiver doesn't make cache line misses to read rtable.
1180 */
1181void ipv4_pktinfo_prepare(const struct sock *sk, struct sk_buff *skb)
1182{
1183 struct in_pktinfo *pktinfo = PKTINFO_SKB_CB(skb);
1184 bool prepare = (inet_sk(sk)->cmsg_flags & IP_CMSG_PKTINFO) ||
1185 ipv6_sk_rxinfo(sk);
1186
1187 if (prepare && skb_rtable(skb)) {
1188 pktinfo->ipi_ifindex = inet_iif(skb);
1189 pktinfo->ipi_spec_dst.s_addr = fib_compute_spec_dst(skb);
1190 } else {
1191 pktinfo->ipi_ifindex = 0;
1192 pktinfo->ipi_spec_dst.s_addr = 0;
1193 }
1194 skb_dst_drop(skb);
1195}
1196
1197int ip_setsockopt(struct sock *sk, int level,
1198 int optname, char __user *optval, unsigned int optlen)
1199{
1200 int err;
1201
1202 if (level != SOL_IP)
1203 return -ENOPROTOOPT;
1204
1205 err = do_ip_setsockopt(sk, level, optname, optval, optlen);
1206#ifdef CONFIG_NETFILTER
1207 /* we need to exclude all possible ENOPROTOOPTs except default case */
1208 if (err == -ENOPROTOOPT && optname != IP_HDRINCL &&
1209 optname != IP_IPSEC_POLICY &&
1210 optname != IP_XFRM_POLICY &&
1211 !ip_mroute_opt(optname)) {
1212 lock_sock(sk);
1213 err = nf_setsockopt(sk, PF_INET, optname, optval, optlen);
1214 release_sock(sk);
1215 }
1216#endif
1217 return err;
1218}
1219EXPORT_SYMBOL(ip_setsockopt);
1220
1221#ifdef CONFIG_COMPAT
1222int compat_ip_setsockopt(struct sock *sk, int level, int optname,
1223 char __user *optval, unsigned int optlen)
1224{
1225 int err;
1226
1227 if (level != SOL_IP)
1228 return -ENOPROTOOPT;
1229
1230 if (optname >= MCAST_JOIN_GROUP && optname <= MCAST_MSFILTER)
1231 return compat_mc_setsockopt(sk, level, optname, optval, optlen,
1232 ip_setsockopt);
1233
1234 err = do_ip_setsockopt(sk, level, optname, optval, optlen);
1235#ifdef CONFIG_NETFILTER
1236 /* we need to exclude all possible ENOPROTOOPTs except default case */
1237 if (err == -ENOPROTOOPT && optname != IP_HDRINCL &&
1238 optname != IP_IPSEC_POLICY &&
1239 optname != IP_XFRM_POLICY &&
1240 !ip_mroute_opt(optname)) {
1241 lock_sock(sk);
1242 err = compat_nf_setsockopt(sk, PF_INET, optname,
1243 optval, optlen);
1244 release_sock(sk);
1245 }
1246#endif
1247 return err;
1248}
1249EXPORT_SYMBOL(compat_ip_setsockopt);
1250#endif
1251
1252/*
1253 * Get the options. Note for future reference. The GET of IP options gets
1254 * the _received_ ones. The set sets the _sent_ ones.
1255 */
1256
1257static bool getsockopt_needs_rtnl(int optname)
1258{
1259 switch (optname) {
1260 case IP_MSFILTER:
1261 case MCAST_MSFILTER:
1262 return true;
1263 }
1264 return false;
1265}
1266
1267static int do_ip_getsockopt(struct sock *sk, int level, int optname,
1268 char __user *optval, int __user *optlen, unsigned int flags)
1269{
1270 struct inet_sock *inet = inet_sk(sk);
1271 bool needs_rtnl = getsockopt_needs_rtnl(optname);
1272 int val, err = 0;
1273 int len;
1274
1275 if (level != SOL_IP)
1276 return -EOPNOTSUPP;
1277
1278 if (ip_mroute_opt(optname))
1279 return ip_mroute_getsockopt(sk, optname, optval, optlen);
1280
1281 if (get_user(len, optlen))
1282 return -EFAULT;
1283 if (len < 0)
1284 return -EINVAL;
1285
1286 if (needs_rtnl)
1287 rtnl_lock();
1288 lock_sock(sk);
1289
1290 switch (optname) {
1291 case IP_OPTIONS:
1292 {
1293 unsigned char optbuf[sizeof(struct ip_options)+40];
1294 struct ip_options *opt = (struct ip_options *)optbuf;
1295 struct ip_options_rcu *inet_opt;
1296
1297 inet_opt = rcu_dereference_protected(inet->inet_opt,
1298 sock_owned_by_user(sk));
1299 opt->optlen = 0;
1300 if (inet_opt)
1301 memcpy(optbuf, &inet_opt->opt,
1302 sizeof(struct ip_options) +
1303 inet_opt->opt.optlen);
1304 release_sock(sk);
1305
1306 if (opt->optlen == 0)
1307 return put_user(0, optlen);
1308
1309 ip_options_undo(opt);
1310
1311 len = min_t(unsigned int, len, opt->optlen);
1312 if (put_user(len, optlen))
1313 return -EFAULT;
1314 if (copy_to_user(optval, opt->__data, len))
1315 return -EFAULT;
1316 return 0;
1317 }
1318 case IP_PKTINFO:
1319 val = (inet->cmsg_flags & IP_CMSG_PKTINFO) != 0;
1320 break;
1321 case IP_RECVTTL:
1322 val = (inet->cmsg_flags & IP_CMSG_TTL) != 0;
1323 break;
1324 case IP_RECVTOS:
1325 val = (inet->cmsg_flags & IP_CMSG_TOS) != 0;
1326 break;
1327 case IP_RECVOPTS:
1328 val = (inet->cmsg_flags & IP_CMSG_RECVOPTS) != 0;
1329 break;
1330 case IP_RETOPTS:
1331 val = (inet->cmsg_flags & IP_CMSG_RETOPTS) != 0;
1332 break;
1333 case IP_PASSSEC:
1334 val = (inet->cmsg_flags & IP_CMSG_PASSSEC) != 0;
1335 break;
1336 case IP_RECVORIGDSTADDR:
1337 val = (inet->cmsg_flags & IP_CMSG_ORIGDSTADDR) != 0;
1338 break;
1339 case IP_CHECKSUM:
1340 val = (inet->cmsg_flags & IP_CMSG_CHECKSUM) != 0;
1341 break;
1342 case IP_TOS:
1343 val = inet->tos;
1344 break;
1345 case IP_TTL:
1346 {
1347 struct net *net = sock_net(sk);
1348 val = (inet->uc_ttl == -1 ?
1349 net->ipv4.sysctl_ip_default_ttl :
1350 inet->uc_ttl);
1351 break;
1352 }
1353 case IP_HDRINCL:
1354 val = inet->hdrincl;
1355 break;
1356 case IP_NODEFRAG:
1357 val = inet->nodefrag;
1358 break;
1359 case IP_BIND_ADDRESS_NO_PORT:
1360 val = inet->bind_address_no_port;
1361 break;
1362 case IP_MTU_DISCOVER:
1363 val = inet->pmtudisc;
1364 break;
1365 case IP_MTU:
1366 {
1367 struct dst_entry *dst;
1368 val = 0;
1369 dst = sk_dst_get(sk);
1370 if (dst) {
1371 val = dst_mtu(dst);
1372 dst_release(dst);
1373 }
1374 if (!val) {
1375 release_sock(sk);
1376 return -ENOTCONN;
1377 }
1378 break;
1379 }
1380 case IP_RECVERR:
1381 val = inet->recverr;
1382 break;
1383 case IP_MULTICAST_TTL:
1384 val = inet->mc_ttl;
1385 break;
1386 case IP_MULTICAST_LOOP:
1387 val = inet->mc_loop;
1388 break;
1389 case IP_UNICAST_IF:
1390 val = (__force int)htonl((__u32) inet->uc_index);
1391 break;
1392 case IP_MULTICAST_IF:
1393 {
1394 struct in_addr addr;
1395 len = min_t(unsigned int, len, sizeof(struct in_addr));
1396 addr.s_addr = inet->mc_addr;
1397 release_sock(sk);
1398
1399 if (put_user(len, optlen))
1400 return -EFAULT;
1401 if (copy_to_user(optval, &addr, len))
1402 return -EFAULT;
1403 return 0;
1404 }
1405 case IP_MSFILTER:
1406 {
1407 struct ip_msfilter msf;
1408
1409 if (len < IP_MSFILTER_SIZE(0)) {
1410 err = -EINVAL;
1411 goto out;
1412 }
1413 if (copy_from_user(&msf, optval, IP_MSFILTER_SIZE(0))) {
1414 err = -EFAULT;
1415 goto out;
1416 }
1417 err = ip_mc_msfget(sk, &msf,
1418 (struct ip_msfilter __user *)optval, optlen);
1419 goto out;
1420 }
1421 case MCAST_MSFILTER:
1422 {
1423 struct group_filter gsf;
1424
1425 if (len < GROUP_FILTER_SIZE(0)) {
1426 err = -EINVAL;
1427 goto out;
1428 }
1429 if (copy_from_user(&gsf, optval, GROUP_FILTER_SIZE(0))) {
1430 err = -EFAULT;
1431 goto out;
1432 }
1433 err = ip_mc_gsfget(sk, &gsf,
1434 (struct group_filter __user *)optval,
1435 optlen);
1436 goto out;
1437 }
1438 case IP_MULTICAST_ALL:
1439 val = inet->mc_all;
1440 break;
1441 case IP_PKTOPTIONS:
1442 {
1443 struct msghdr msg;
1444
1445 release_sock(sk);
1446
1447 if (sk->sk_type != SOCK_STREAM)
1448 return -ENOPROTOOPT;
1449
1450 msg.msg_control = (__force void *) optval;
1451 msg.msg_controllen = len;
1452 msg.msg_flags = flags;
1453
1454 if (inet->cmsg_flags & IP_CMSG_PKTINFO) {
1455 struct in_pktinfo info;
1456
1457 info.ipi_addr.s_addr = inet->inet_rcv_saddr;
1458 info.ipi_spec_dst.s_addr = inet->inet_rcv_saddr;
1459 info.ipi_ifindex = inet->mc_index;
1460 put_cmsg(&msg, SOL_IP, IP_PKTINFO, sizeof(info), &info);
1461 }
1462 if (inet->cmsg_flags & IP_CMSG_TTL) {
1463 int hlim = inet->mc_ttl;
1464 put_cmsg(&msg, SOL_IP, IP_TTL, sizeof(hlim), &hlim);
1465 }
1466 if (inet->cmsg_flags & IP_CMSG_TOS) {
1467 int tos = inet->rcv_tos;
1468 put_cmsg(&msg, SOL_IP, IP_TOS, sizeof(tos), &tos);
1469 }
1470 len -= msg.msg_controllen;
1471 return put_user(len, optlen);
1472 }
1473 case IP_FREEBIND:
1474 val = inet->freebind;
1475 break;
1476 case IP_TRANSPARENT:
1477 val = inet->transparent;
1478 break;
1479 case IP_MINTTL:
1480 val = inet->min_ttl;
1481 break;
1482 default:
1483 release_sock(sk);
1484 return -ENOPROTOOPT;
1485 }
1486 release_sock(sk);
1487
1488 if (len < sizeof(int) && len > 0 && val >= 0 && val <= 255) {
1489 unsigned char ucval = (unsigned char)val;
1490 len = 1;
1491 if (put_user(len, optlen))
1492 return -EFAULT;
1493 if (copy_to_user(optval, &ucval, 1))
1494 return -EFAULT;
1495 } else {
1496 len = min_t(unsigned int, sizeof(int), len);
1497 if (put_user(len, optlen))
1498 return -EFAULT;
1499 if (copy_to_user(optval, &val, len))
1500 return -EFAULT;
1501 }
1502 return 0;
1503
1504out:
1505 release_sock(sk);
1506 if (needs_rtnl)
1507 rtnl_unlock();
1508 return err;
1509}
1510
1511int ip_getsockopt(struct sock *sk, int level,
1512 int optname, char __user *optval, int __user *optlen)
1513{
1514 int err;
1515
1516 err = do_ip_getsockopt(sk, level, optname, optval, optlen, 0);
1517#ifdef CONFIG_NETFILTER
1518 /* we need to exclude all possible ENOPROTOOPTs except default case */
1519 if (err == -ENOPROTOOPT && optname != IP_PKTOPTIONS &&
1520 !ip_mroute_opt(optname)) {
1521 int len;
1522
1523 if (get_user(len, optlen))
1524 return -EFAULT;
1525
1526 lock_sock(sk);
1527 err = nf_getsockopt(sk, PF_INET, optname, optval,
1528 &len);
1529 release_sock(sk);
1530 if (err >= 0)
1531 err = put_user(len, optlen);
1532 return err;
1533 }
1534#endif
1535 return err;
1536}
1537EXPORT_SYMBOL(ip_getsockopt);
1538
1539#ifdef CONFIG_COMPAT
1540int compat_ip_getsockopt(struct sock *sk, int level, int optname,
1541 char __user *optval, int __user *optlen)
1542{
1543 int err;
1544
1545 if (optname == MCAST_MSFILTER)
1546 return compat_mc_getsockopt(sk, level, optname, optval, optlen,
1547 ip_getsockopt);
1548
1549 err = do_ip_getsockopt(sk, level, optname, optval, optlen,
1550 MSG_CMSG_COMPAT);
1551
1552#ifdef CONFIG_NETFILTER
1553 /* we need to exclude all possible ENOPROTOOPTs except default case */
1554 if (err == -ENOPROTOOPT && optname != IP_PKTOPTIONS &&
1555 !ip_mroute_opt(optname)) {
1556 int len;
1557
1558 if (get_user(len, optlen))
1559 return -EFAULT;
1560
1561 lock_sock(sk);
1562 err = compat_nf_getsockopt(sk, PF_INET, optname, optval, &len);
1563 release_sock(sk);
1564 if (err >= 0)
1565 err = put_user(len, optlen);
1566 return err;
1567 }
1568#endif
1569 return err;
1570}
1571EXPORT_SYMBOL(compat_ip_getsockopt);
1572#endif
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * INET An implementation of the TCP/IP protocol suite for the LINUX
4 * operating system. INET is implemented using the BSD Socket
5 * interface as the means of communication with the user level.
6 *
7 * The IP to API glue.
8 *
9 * Authors: see ip.c
10 *
11 * Fixes:
12 * Many : Split from ip.c , see ip.c for history.
13 * Martin Mares : TOS setting fixed.
14 * Alan Cox : Fixed a couple of oopses in Martin's
15 * TOS tweaks.
16 * Mike McLagan : Routing by source
17 */
18
19#include <linux/module.h>
20#include <linux/types.h>
21#include <linux/mm.h>
22#include <linux/skbuff.h>
23#include <linux/ip.h>
24#include <linux/icmp.h>
25#include <linux/inetdevice.h>
26#include <linux/netdevice.h>
27#include <linux/slab.h>
28#include <net/sock.h>
29#include <net/ip.h>
30#include <net/icmp.h>
31#include <net/tcp_states.h>
32#include <linux/udp.h>
33#include <linux/igmp.h>
34#include <linux/netfilter.h>
35#include <linux/route.h>
36#include <linux/mroute.h>
37#include <net/inet_ecn.h>
38#include <net/route.h>
39#include <net/xfrm.h>
40#include <net/compat.h>
41#include <net/checksum.h>
42#if IS_ENABLED(CONFIG_IPV6)
43#include <net/transp_v6.h>
44#endif
45#include <net/ip_fib.h>
46
47#include <linux/errqueue.h>
48#include <linux/uaccess.h>
49
50/*
51 * SOL_IP control messages.
52 */
53
54static void ip_cmsg_recv_pktinfo(struct msghdr *msg, struct sk_buff *skb)
55{
56 struct in_pktinfo info = *PKTINFO_SKB_CB(skb);
57
58 info.ipi_addr.s_addr = ip_hdr(skb)->daddr;
59
60 put_cmsg(msg, SOL_IP, IP_PKTINFO, sizeof(info), &info);
61}
62
63static void ip_cmsg_recv_ttl(struct msghdr *msg, struct sk_buff *skb)
64{
65 int ttl = ip_hdr(skb)->ttl;
66 put_cmsg(msg, SOL_IP, IP_TTL, sizeof(int), &ttl);
67}
68
69static void ip_cmsg_recv_tos(struct msghdr *msg, struct sk_buff *skb)
70{
71 put_cmsg(msg, SOL_IP, IP_TOS, 1, &ip_hdr(skb)->tos);
72}
73
74static void ip_cmsg_recv_opts(struct msghdr *msg, struct sk_buff *skb)
75{
76 if (IPCB(skb)->opt.optlen == 0)
77 return;
78
79 put_cmsg(msg, SOL_IP, IP_RECVOPTS, IPCB(skb)->opt.optlen,
80 ip_hdr(skb) + 1);
81}
82
83
84static void ip_cmsg_recv_retopts(struct net *net, struct msghdr *msg,
85 struct sk_buff *skb)
86{
87 unsigned char optbuf[sizeof(struct ip_options) + 40];
88 struct ip_options *opt = (struct ip_options *)optbuf;
89
90 if (IPCB(skb)->opt.optlen == 0)
91 return;
92
93 if (ip_options_echo(net, opt, skb)) {
94 msg->msg_flags |= MSG_CTRUNC;
95 return;
96 }
97 ip_options_undo(opt);
98
99 put_cmsg(msg, SOL_IP, IP_RETOPTS, opt->optlen, opt->__data);
100}
101
102static void ip_cmsg_recv_fragsize(struct msghdr *msg, struct sk_buff *skb)
103{
104 int val;
105
106 if (IPCB(skb)->frag_max_size == 0)
107 return;
108
109 val = IPCB(skb)->frag_max_size;
110 put_cmsg(msg, SOL_IP, IP_RECVFRAGSIZE, sizeof(val), &val);
111}
112
113static void ip_cmsg_recv_checksum(struct msghdr *msg, struct sk_buff *skb,
114 int tlen, int offset)
115{
116 __wsum csum = skb->csum;
117
118 if (skb->ip_summed != CHECKSUM_COMPLETE)
119 return;
120
121 if (offset != 0) {
122 int tend_off = skb_transport_offset(skb) + tlen;
123 csum = csum_sub(csum, skb_checksum(skb, tend_off, offset, 0));
124 }
125
126 put_cmsg(msg, SOL_IP, IP_CHECKSUM, sizeof(__wsum), &csum);
127}
128
129static void ip_cmsg_recv_security(struct msghdr *msg, struct sk_buff *skb)
130{
131 char *secdata;
132 u32 seclen, secid;
133 int err;
134
135 err = security_socket_getpeersec_dgram(NULL, skb, &secid);
136 if (err)
137 return;
138
139 err = security_secid_to_secctx(secid, &secdata, &seclen);
140 if (err)
141 return;
142
143 put_cmsg(msg, SOL_IP, SCM_SECURITY, seclen, secdata);
144 security_release_secctx(secdata, seclen);
145}
146
147static void ip_cmsg_recv_dstaddr(struct msghdr *msg, struct sk_buff *skb)
148{
149 __be16 _ports[2], *ports;
150 struct sockaddr_in sin;
151
152 /* All current transport protocols have the port numbers in the
153 * first four bytes of the transport header and this function is
154 * written with this assumption in mind.
155 */
156 ports = skb_header_pointer(skb, skb_transport_offset(skb),
157 sizeof(_ports), &_ports);
158 if (!ports)
159 return;
160
161 sin.sin_family = AF_INET;
162 sin.sin_addr.s_addr = ip_hdr(skb)->daddr;
163 sin.sin_port = ports[1];
164 memset(sin.sin_zero, 0, sizeof(sin.sin_zero));
165
166 put_cmsg(msg, SOL_IP, IP_ORIGDSTADDR, sizeof(sin), &sin);
167}
168
169void ip_cmsg_recv_offset(struct msghdr *msg, struct sock *sk,
170 struct sk_buff *skb, int tlen, int offset)
171{
172 unsigned long flags = inet_cmsg_flags(inet_sk(sk));
173
174 if (!flags)
175 return;
176
177 /* Ordered by supposed usage frequency */
178 if (flags & IP_CMSG_PKTINFO) {
179 ip_cmsg_recv_pktinfo(msg, skb);
180
181 flags &= ~IP_CMSG_PKTINFO;
182 if (!flags)
183 return;
184 }
185
186 if (flags & IP_CMSG_TTL) {
187 ip_cmsg_recv_ttl(msg, skb);
188
189 flags &= ~IP_CMSG_TTL;
190 if (!flags)
191 return;
192 }
193
194 if (flags & IP_CMSG_TOS) {
195 ip_cmsg_recv_tos(msg, skb);
196
197 flags &= ~IP_CMSG_TOS;
198 if (!flags)
199 return;
200 }
201
202 if (flags & IP_CMSG_RECVOPTS) {
203 ip_cmsg_recv_opts(msg, skb);
204
205 flags &= ~IP_CMSG_RECVOPTS;
206 if (!flags)
207 return;
208 }
209
210 if (flags & IP_CMSG_RETOPTS) {
211 ip_cmsg_recv_retopts(sock_net(sk), msg, skb);
212
213 flags &= ~IP_CMSG_RETOPTS;
214 if (!flags)
215 return;
216 }
217
218 if (flags & IP_CMSG_PASSSEC) {
219 ip_cmsg_recv_security(msg, skb);
220
221 flags &= ~IP_CMSG_PASSSEC;
222 if (!flags)
223 return;
224 }
225
226 if (flags & IP_CMSG_ORIGDSTADDR) {
227 ip_cmsg_recv_dstaddr(msg, skb);
228
229 flags &= ~IP_CMSG_ORIGDSTADDR;
230 if (!flags)
231 return;
232 }
233
234 if (flags & IP_CMSG_CHECKSUM)
235 ip_cmsg_recv_checksum(msg, skb, tlen, offset);
236
237 if (flags & IP_CMSG_RECVFRAGSIZE)
238 ip_cmsg_recv_fragsize(msg, skb);
239}
240EXPORT_SYMBOL(ip_cmsg_recv_offset);
241
242int ip_cmsg_send(struct sock *sk, struct msghdr *msg, struct ipcm_cookie *ipc,
243 bool allow_ipv6)
244{
245 int err, val;
246 struct cmsghdr *cmsg;
247 struct net *net = sock_net(sk);
248
249 for_each_cmsghdr(cmsg, msg) {
250 if (!CMSG_OK(msg, cmsg))
251 return -EINVAL;
252#if IS_ENABLED(CONFIG_IPV6)
253 if (allow_ipv6 &&
254 cmsg->cmsg_level == SOL_IPV6 &&
255 cmsg->cmsg_type == IPV6_PKTINFO) {
256 struct in6_pktinfo *src_info;
257
258 if (cmsg->cmsg_len < CMSG_LEN(sizeof(*src_info)))
259 return -EINVAL;
260 src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg);
261 if (!ipv6_addr_v4mapped(&src_info->ipi6_addr))
262 return -EINVAL;
263 if (src_info->ipi6_ifindex)
264 ipc->oif = src_info->ipi6_ifindex;
265 ipc->addr = src_info->ipi6_addr.s6_addr32[3];
266 continue;
267 }
268#endif
269 if (cmsg->cmsg_level == SOL_SOCKET) {
270 err = __sock_cmsg_send(sk, cmsg, &ipc->sockc);
271 if (err)
272 return err;
273 continue;
274 }
275
276 if (cmsg->cmsg_level != SOL_IP)
277 continue;
278 switch (cmsg->cmsg_type) {
279 case IP_RETOPTS:
280 err = cmsg->cmsg_len - sizeof(struct cmsghdr);
281
282 /* Our caller is responsible for freeing ipc->opt */
283 err = ip_options_get(net, &ipc->opt,
284 KERNEL_SOCKPTR(CMSG_DATA(cmsg)),
285 err < 40 ? err : 40);
286 if (err)
287 return err;
288 break;
289 case IP_PKTINFO:
290 {
291 struct in_pktinfo *info;
292 if (cmsg->cmsg_len != CMSG_LEN(sizeof(struct in_pktinfo)))
293 return -EINVAL;
294 info = (struct in_pktinfo *)CMSG_DATA(cmsg);
295 if (info->ipi_ifindex)
296 ipc->oif = info->ipi_ifindex;
297 ipc->addr = info->ipi_spec_dst.s_addr;
298 break;
299 }
300 case IP_TTL:
301 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
302 return -EINVAL;
303 val = *(int *)CMSG_DATA(cmsg);
304 if (val < 1 || val > 255)
305 return -EINVAL;
306 ipc->ttl = val;
307 break;
308 case IP_TOS:
309 if (cmsg->cmsg_len == CMSG_LEN(sizeof(int)))
310 val = *(int *)CMSG_DATA(cmsg);
311 else if (cmsg->cmsg_len == CMSG_LEN(sizeof(u8)))
312 val = *(u8 *)CMSG_DATA(cmsg);
313 else
314 return -EINVAL;
315 if (val < 0 || val > 255)
316 return -EINVAL;
317 ipc->tos = val;
318 ipc->priority = rt_tos2priority(ipc->tos);
319 break;
320 case IP_PROTOCOL:
321 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
322 return -EINVAL;
323 val = *(int *)CMSG_DATA(cmsg);
324 if (val < 1 || val > 255)
325 return -EINVAL;
326 ipc->protocol = val;
327 break;
328 default:
329 return -EINVAL;
330 }
331 }
332 return 0;
333}
334
335static void ip_ra_destroy_rcu(struct rcu_head *head)
336{
337 struct ip_ra_chain *ra = container_of(head, struct ip_ra_chain, rcu);
338
339 sock_put(ra->saved_sk);
340 kfree(ra);
341}
342
343int ip_ra_control(struct sock *sk, unsigned char on,
344 void (*destructor)(struct sock *))
345{
346 struct ip_ra_chain *ra, *new_ra;
347 struct ip_ra_chain __rcu **rap;
348 struct net *net = sock_net(sk);
349
350 if (sk->sk_type != SOCK_RAW || inet_sk(sk)->inet_num == IPPROTO_RAW)
351 return -EINVAL;
352
353 new_ra = on ? kmalloc(sizeof(*new_ra), GFP_KERNEL) : NULL;
354 if (on && !new_ra)
355 return -ENOMEM;
356
357 mutex_lock(&net->ipv4.ra_mutex);
358 for (rap = &net->ipv4.ra_chain;
359 (ra = rcu_dereference_protected(*rap,
360 lockdep_is_held(&net->ipv4.ra_mutex))) != NULL;
361 rap = &ra->next) {
362 if (ra->sk == sk) {
363 if (on) {
364 mutex_unlock(&net->ipv4.ra_mutex);
365 kfree(new_ra);
366 return -EADDRINUSE;
367 }
368 /* dont let ip_call_ra_chain() use sk again */
369 ra->sk = NULL;
370 RCU_INIT_POINTER(*rap, ra->next);
371 mutex_unlock(&net->ipv4.ra_mutex);
372
373 if (ra->destructor)
374 ra->destructor(sk);
375 /*
376 * Delay sock_put(sk) and kfree(ra) after one rcu grace
377 * period. This guarantee ip_call_ra_chain() dont need
378 * to mess with socket refcounts.
379 */
380 ra->saved_sk = sk;
381 call_rcu(&ra->rcu, ip_ra_destroy_rcu);
382 return 0;
383 }
384 }
385 if (!new_ra) {
386 mutex_unlock(&net->ipv4.ra_mutex);
387 return -ENOBUFS;
388 }
389 new_ra->sk = sk;
390 new_ra->destructor = destructor;
391
392 RCU_INIT_POINTER(new_ra->next, ra);
393 rcu_assign_pointer(*rap, new_ra);
394 sock_hold(sk);
395 mutex_unlock(&net->ipv4.ra_mutex);
396
397 return 0;
398}
399
400static void ipv4_icmp_error_rfc4884(const struct sk_buff *skb,
401 struct sock_ee_data_rfc4884 *out)
402{
403 switch (icmp_hdr(skb)->type) {
404 case ICMP_DEST_UNREACH:
405 case ICMP_TIME_EXCEEDED:
406 case ICMP_PARAMETERPROB:
407 ip_icmp_error_rfc4884(skb, out, sizeof(struct icmphdr),
408 icmp_hdr(skb)->un.reserved[1] * 4);
409 }
410}
411
412void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
413 __be16 port, u32 info, u8 *payload)
414{
415 struct sock_exterr_skb *serr;
416
417 skb = skb_clone(skb, GFP_ATOMIC);
418 if (!skb)
419 return;
420
421 serr = SKB_EXT_ERR(skb);
422 serr->ee.ee_errno = err;
423 serr->ee.ee_origin = SO_EE_ORIGIN_ICMP;
424 serr->ee.ee_type = icmp_hdr(skb)->type;
425 serr->ee.ee_code = icmp_hdr(skb)->code;
426 serr->ee.ee_pad = 0;
427 serr->ee.ee_info = info;
428 serr->ee.ee_data = 0;
429 serr->addr_offset = (u8 *)&(((struct iphdr *)(icmp_hdr(skb) + 1))->daddr) -
430 skb_network_header(skb);
431 serr->port = port;
432
433 if (skb_pull(skb, payload - skb->data)) {
434 if (inet_test_bit(RECVERR_RFC4884, sk))
435 ipv4_icmp_error_rfc4884(skb, &serr->ee.ee_rfc4884);
436
437 skb_reset_transport_header(skb);
438 if (sock_queue_err_skb(sk, skb) == 0)
439 return;
440 }
441 kfree_skb(skb);
442}
443EXPORT_SYMBOL_GPL(ip_icmp_error);
444
445void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 port, u32 info)
446{
447 struct sock_exterr_skb *serr;
448 struct iphdr *iph;
449 struct sk_buff *skb;
450
451 if (!inet_test_bit(RECVERR, sk))
452 return;
453
454 skb = alloc_skb(sizeof(struct iphdr), GFP_ATOMIC);
455 if (!skb)
456 return;
457
458 skb_put(skb, sizeof(struct iphdr));
459 skb_reset_network_header(skb);
460 iph = ip_hdr(skb);
461 iph->daddr = daddr;
462
463 serr = SKB_EXT_ERR(skb);
464 serr->ee.ee_errno = err;
465 serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
466 serr->ee.ee_type = 0;
467 serr->ee.ee_code = 0;
468 serr->ee.ee_pad = 0;
469 serr->ee.ee_info = info;
470 serr->ee.ee_data = 0;
471 serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
472 serr->port = port;
473
474 __skb_pull(skb, skb_tail_pointer(skb) - skb->data);
475 skb_reset_transport_header(skb);
476
477 if (sock_queue_err_skb(sk, skb))
478 kfree_skb(skb);
479}
480
481/* For some errors we have valid addr_offset even with zero payload and
482 * zero port. Also, addr_offset should be supported if port is set.
483 */
484static inline bool ipv4_datagram_support_addr(struct sock_exterr_skb *serr)
485{
486 return serr->ee.ee_origin == SO_EE_ORIGIN_ICMP ||
487 serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL || serr->port;
488}
489
490/* IPv4 supports cmsg on all imcp errors and some timestamps
491 *
492 * Timestamp code paths do not initialize the fields expected by cmsg:
493 * the PKTINFO fields in skb->cb[]. Fill those in here.
494 */
495static bool ipv4_datagram_support_cmsg(const struct sock *sk,
496 struct sk_buff *skb,
497 int ee_origin)
498{
499 struct in_pktinfo *info;
500
501 if (ee_origin == SO_EE_ORIGIN_ICMP)
502 return true;
503
504 if (ee_origin == SO_EE_ORIGIN_LOCAL)
505 return false;
506
507 /* Support IP_PKTINFO on tstamp packets if requested, to correlate
508 * timestamp with egress dev. Not possible for packets without iif
509 * or without payload (SOF_TIMESTAMPING_OPT_TSONLY).
510 */
511 info = PKTINFO_SKB_CB(skb);
512 if (!(READ_ONCE(sk->sk_tsflags) & SOF_TIMESTAMPING_OPT_CMSG) ||
513 !info->ipi_ifindex)
514 return false;
515
516 info->ipi_spec_dst.s_addr = ip_hdr(skb)->saddr;
517 return true;
518}
519
520/*
521 * Handle MSG_ERRQUEUE
522 */
523int ip_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
524{
525 struct sock_exterr_skb *serr;
526 struct sk_buff *skb;
527 DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name);
528 struct {
529 struct sock_extended_err ee;
530 struct sockaddr_in offender;
531 } errhdr;
532 int err;
533 int copied;
534
535 err = -EAGAIN;
536 skb = sock_dequeue_err_skb(sk);
537 if (!skb)
538 goto out;
539
540 copied = skb->len;
541 if (copied > len) {
542 msg->msg_flags |= MSG_TRUNC;
543 copied = len;
544 }
545 err = skb_copy_datagram_msg(skb, 0, msg, copied);
546 if (unlikely(err)) {
547 kfree_skb(skb);
548 return err;
549 }
550 sock_recv_timestamp(msg, sk, skb);
551
552 serr = SKB_EXT_ERR(skb);
553
554 if (sin && ipv4_datagram_support_addr(serr)) {
555 sin->sin_family = AF_INET;
556 sin->sin_addr.s_addr = *(__be32 *)(skb_network_header(skb) +
557 serr->addr_offset);
558 sin->sin_port = serr->port;
559 memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
560 *addr_len = sizeof(*sin);
561 }
562
563 memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
564 sin = &errhdr.offender;
565 memset(sin, 0, sizeof(*sin));
566
567 if (ipv4_datagram_support_cmsg(sk, skb, serr->ee.ee_origin)) {
568 sin->sin_family = AF_INET;
569 sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
570 if (inet_cmsg_flags(inet_sk(sk)))
571 ip_cmsg_recv(msg, skb);
572 }
573
574 put_cmsg(msg, SOL_IP, IP_RECVERR, sizeof(errhdr), &errhdr);
575
576 /* Now we could try to dump offended packet options */
577
578 msg->msg_flags |= MSG_ERRQUEUE;
579 err = copied;
580
581 consume_skb(skb);
582out:
583 return err;
584}
585
586void __ip_sock_set_tos(struct sock *sk, int val)
587{
588 u8 old_tos = inet_sk(sk)->tos;
589
590 if (sk->sk_type == SOCK_STREAM) {
591 val &= ~INET_ECN_MASK;
592 val |= old_tos & INET_ECN_MASK;
593 }
594 if (old_tos != val) {
595 WRITE_ONCE(inet_sk(sk)->tos, val);
596 WRITE_ONCE(sk->sk_priority, rt_tos2priority(val));
597 sk_dst_reset(sk);
598 }
599}
600
601void ip_sock_set_tos(struct sock *sk, int val)
602{
603 sockopt_lock_sock(sk);
604 __ip_sock_set_tos(sk, val);
605 sockopt_release_sock(sk);
606}
607EXPORT_SYMBOL(ip_sock_set_tos);
608
609void ip_sock_set_freebind(struct sock *sk)
610{
611 inet_set_bit(FREEBIND, sk);
612}
613EXPORT_SYMBOL(ip_sock_set_freebind);
614
615void ip_sock_set_recverr(struct sock *sk)
616{
617 inet_set_bit(RECVERR, sk);
618}
619EXPORT_SYMBOL(ip_sock_set_recverr);
620
621int ip_sock_set_mtu_discover(struct sock *sk, int val)
622{
623 if (val < IP_PMTUDISC_DONT || val > IP_PMTUDISC_OMIT)
624 return -EINVAL;
625 WRITE_ONCE(inet_sk(sk)->pmtudisc, val);
626 return 0;
627}
628EXPORT_SYMBOL(ip_sock_set_mtu_discover);
629
630void ip_sock_set_pktinfo(struct sock *sk)
631{
632 inet_set_bit(PKTINFO, sk);
633}
634EXPORT_SYMBOL(ip_sock_set_pktinfo);
635
636/*
637 * Socket option code for IP. This is the end of the line after any
638 * TCP,UDP etc options on an IP socket.
639 */
640static bool setsockopt_needs_rtnl(int optname)
641{
642 switch (optname) {
643 case IP_ADD_MEMBERSHIP:
644 case IP_ADD_SOURCE_MEMBERSHIP:
645 case IP_BLOCK_SOURCE:
646 case IP_DROP_MEMBERSHIP:
647 case IP_DROP_SOURCE_MEMBERSHIP:
648 case IP_MSFILTER:
649 case IP_UNBLOCK_SOURCE:
650 case MCAST_BLOCK_SOURCE:
651 case MCAST_MSFILTER:
652 case MCAST_JOIN_GROUP:
653 case MCAST_JOIN_SOURCE_GROUP:
654 case MCAST_LEAVE_GROUP:
655 case MCAST_LEAVE_SOURCE_GROUP:
656 case MCAST_UNBLOCK_SOURCE:
657 return true;
658 }
659 return false;
660}
661
662static int set_mcast_msfilter(struct sock *sk, int ifindex,
663 int numsrc, int fmode,
664 struct sockaddr_storage *group,
665 struct sockaddr_storage *list)
666{
667 struct ip_msfilter *msf;
668 struct sockaddr_in *psin;
669 int err, i;
670
671 msf = kmalloc(IP_MSFILTER_SIZE(numsrc), GFP_KERNEL);
672 if (!msf)
673 return -ENOBUFS;
674
675 psin = (struct sockaddr_in *)group;
676 if (psin->sin_family != AF_INET)
677 goto Eaddrnotavail;
678 msf->imsf_multiaddr = psin->sin_addr.s_addr;
679 msf->imsf_interface = 0;
680 msf->imsf_fmode = fmode;
681 msf->imsf_numsrc = numsrc;
682 for (i = 0; i < numsrc; ++i) {
683 psin = (struct sockaddr_in *)&list[i];
684
685 if (psin->sin_family != AF_INET)
686 goto Eaddrnotavail;
687 msf->imsf_slist_flex[i] = psin->sin_addr.s_addr;
688 }
689 err = ip_mc_msfilter(sk, msf, ifindex);
690 kfree(msf);
691 return err;
692
693Eaddrnotavail:
694 kfree(msf);
695 return -EADDRNOTAVAIL;
696}
697
698static int copy_group_source_from_sockptr(struct group_source_req *greqs,
699 sockptr_t optval, int optlen)
700{
701 if (in_compat_syscall()) {
702 struct compat_group_source_req gr32;
703
704 if (optlen != sizeof(gr32))
705 return -EINVAL;
706 if (copy_from_sockptr(&gr32, optval, sizeof(gr32)))
707 return -EFAULT;
708 greqs->gsr_interface = gr32.gsr_interface;
709 greqs->gsr_group = gr32.gsr_group;
710 greqs->gsr_source = gr32.gsr_source;
711 } else {
712 if (optlen != sizeof(*greqs))
713 return -EINVAL;
714 if (copy_from_sockptr(greqs, optval, sizeof(*greqs)))
715 return -EFAULT;
716 }
717
718 return 0;
719}
720
721static int do_mcast_group_source(struct sock *sk, int optname,
722 sockptr_t optval, int optlen)
723{
724 struct group_source_req greqs;
725 struct ip_mreq_source mreqs;
726 struct sockaddr_in *psin;
727 int omode, add, err;
728
729 err = copy_group_source_from_sockptr(&greqs, optval, optlen);
730 if (err)
731 return err;
732
733 if (greqs.gsr_group.ss_family != AF_INET ||
734 greqs.gsr_source.ss_family != AF_INET)
735 return -EADDRNOTAVAIL;
736
737 psin = (struct sockaddr_in *)&greqs.gsr_group;
738 mreqs.imr_multiaddr = psin->sin_addr.s_addr;
739 psin = (struct sockaddr_in *)&greqs.gsr_source;
740 mreqs.imr_sourceaddr = psin->sin_addr.s_addr;
741 mreqs.imr_interface = 0; /* use index for mc_source */
742
743 if (optname == MCAST_BLOCK_SOURCE) {
744 omode = MCAST_EXCLUDE;
745 add = 1;
746 } else if (optname == MCAST_UNBLOCK_SOURCE) {
747 omode = MCAST_EXCLUDE;
748 add = 0;
749 } else if (optname == MCAST_JOIN_SOURCE_GROUP) {
750 struct ip_mreqn mreq;
751
752 psin = (struct sockaddr_in *)&greqs.gsr_group;
753 mreq.imr_multiaddr = psin->sin_addr;
754 mreq.imr_address.s_addr = 0;
755 mreq.imr_ifindex = greqs.gsr_interface;
756 err = ip_mc_join_group_ssm(sk, &mreq, MCAST_INCLUDE);
757 if (err && err != -EADDRINUSE)
758 return err;
759 greqs.gsr_interface = mreq.imr_ifindex;
760 omode = MCAST_INCLUDE;
761 add = 1;
762 } else /* MCAST_LEAVE_SOURCE_GROUP */ {
763 omode = MCAST_INCLUDE;
764 add = 0;
765 }
766 return ip_mc_source(add, omode, sk, &mreqs, greqs.gsr_interface);
767}
768
769static int ip_set_mcast_msfilter(struct sock *sk, sockptr_t optval, int optlen)
770{
771 struct group_filter *gsf = NULL;
772 int err;
773
774 if (optlen < GROUP_FILTER_SIZE(0))
775 return -EINVAL;
776 if (optlen > READ_ONCE(sock_net(sk)->core.sysctl_optmem_max))
777 return -ENOBUFS;
778
779 gsf = memdup_sockptr(optval, optlen);
780 if (IS_ERR(gsf))
781 return PTR_ERR(gsf);
782
783 /* numsrc >= (4G-140)/128 overflow in 32 bits */
784 err = -ENOBUFS;
785 if (gsf->gf_numsrc >= 0x1ffffff ||
786 gsf->gf_numsrc > READ_ONCE(sock_net(sk)->ipv4.sysctl_igmp_max_msf))
787 goto out_free_gsf;
788
789 err = -EINVAL;
790 if (GROUP_FILTER_SIZE(gsf->gf_numsrc) > optlen)
791 goto out_free_gsf;
792
793 err = set_mcast_msfilter(sk, gsf->gf_interface, gsf->gf_numsrc,
794 gsf->gf_fmode, &gsf->gf_group,
795 gsf->gf_slist_flex);
796out_free_gsf:
797 kfree(gsf);
798 return err;
799}
800
801static int compat_ip_set_mcast_msfilter(struct sock *sk, sockptr_t optval,
802 int optlen)
803{
804 const int size0 = offsetof(struct compat_group_filter, gf_slist_flex);
805 struct compat_group_filter *gf32;
806 unsigned int n;
807 void *p;
808 int err;
809
810 if (optlen < size0)
811 return -EINVAL;
812 if (optlen > READ_ONCE(sock_net(sk)->core.sysctl_optmem_max) - 4)
813 return -ENOBUFS;
814
815 p = kmalloc(optlen + 4, GFP_KERNEL);
816 if (!p)
817 return -ENOMEM;
818 gf32 = p + 4; /* we want ->gf_group and ->gf_slist_flex aligned */
819
820 err = -EFAULT;
821 if (copy_from_sockptr(gf32, optval, optlen))
822 goto out_free_gsf;
823
824 /* numsrc >= (4G-140)/128 overflow in 32 bits */
825 n = gf32->gf_numsrc;
826 err = -ENOBUFS;
827 if (n >= 0x1ffffff)
828 goto out_free_gsf;
829
830 err = -EINVAL;
831 if (offsetof(struct compat_group_filter, gf_slist_flex[n]) > optlen)
832 goto out_free_gsf;
833
834 /* numsrc >= (4G-140)/128 overflow in 32 bits */
835 err = -ENOBUFS;
836 if (n > READ_ONCE(sock_net(sk)->ipv4.sysctl_igmp_max_msf))
837 goto out_free_gsf;
838 err = set_mcast_msfilter(sk, gf32->gf_interface, n, gf32->gf_fmode,
839 &gf32->gf_group, gf32->gf_slist_flex);
840out_free_gsf:
841 kfree(p);
842 return err;
843}
844
845static int ip_mcast_join_leave(struct sock *sk, int optname,
846 sockptr_t optval, int optlen)
847{
848 struct ip_mreqn mreq = { };
849 struct sockaddr_in *psin;
850 struct group_req greq;
851
852 if (optlen < sizeof(struct group_req))
853 return -EINVAL;
854 if (copy_from_sockptr(&greq, optval, sizeof(greq)))
855 return -EFAULT;
856
857 psin = (struct sockaddr_in *)&greq.gr_group;
858 if (psin->sin_family != AF_INET)
859 return -EINVAL;
860 mreq.imr_multiaddr = psin->sin_addr;
861 mreq.imr_ifindex = greq.gr_interface;
862 if (optname == MCAST_JOIN_GROUP)
863 return ip_mc_join_group(sk, &mreq);
864 return ip_mc_leave_group(sk, &mreq);
865}
866
867static int compat_ip_mcast_join_leave(struct sock *sk, int optname,
868 sockptr_t optval, int optlen)
869{
870 struct compat_group_req greq;
871 struct ip_mreqn mreq = { };
872 struct sockaddr_in *psin;
873
874 if (optlen < sizeof(struct compat_group_req))
875 return -EINVAL;
876 if (copy_from_sockptr(&greq, optval, sizeof(greq)))
877 return -EFAULT;
878
879 psin = (struct sockaddr_in *)&greq.gr_group;
880 if (psin->sin_family != AF_INET)
881 return -EINVAL;
882 mreq.imr_multiaddr = psin->sin_addr;
883 mreq.imr_ifindex = greq.gr_interface;
884
885 if (optname == MCAST_JOIN_GROUP)
886 return ip_mc_join_group(sk, &mreq);
887 return ip_mc_leave_group(sk, &mreq);
888}
889
890DEFINE_STATIC_KEY_FALSE(ip4_min_ttl);
891
892int do_ip_setsockopt(struct sock *sk, int level, int optname,
893 sockptr_t optval, unsigned int optlen)
894{
895 struct inet_sock *inet = inet_sk(sk);
896 struct net *net = sock_net(sk);
897 int val = 0, err, retv;
898 bool needs_rtnl = setsockopt_needs_rtnl(optname);
899
900 switch (optname) {
901 case IP_PKTINFO:
902 case IP_RECVTTL:
903 case IP_RECVOPTS:
904 case IP_RECVTOS:
905 case IP_RETOPTS:
906 case IP_TOS:
907 case IP_TTL:
908 case IP_HDRINCL:
909 case IP_MTU_DISCOVER:
910 case IP_RECVERR:
911 case IP_ROUTER_ALERT:
912 case IP_FREEBIND:
913 case IP_PASSSEC:
914 case IP_TRANSPARENT:
915 case IP_MINTTL:
916 case IP_NODEFRAG:
917 case IP_BIND_ADDRESS_NO_PORT:
918 case IP_UNICAST_IF:
919 case IP_MULTICAST_TTL:
920 case IP_MULTICAST_ALL:
921 case IP_MULTICAST_LOOP:
922 case IP_RECVORIGDSTADDR:
923 case IP_CHECKSUM:
924 case IP_RECVFRAGSIZE:
925 case IP_RECVERR_RFC4884:
926 case IP_LOCAL_PORT_RANGE:
927 if (optlen >= sizeof(int)) {
928 if (copy_from_sockptr(&val, optval, sizeof(val)))
929 return -EFAULT;
930 } else if (optlen >= sizeof(char)) {
931 unsigned char ucval;
932
933 if (copy_from_sockptr(&ucval, optval, sizeof(ucval)))
934 return -EFAULT;
935 val = (int) ucval;
936 }
937 }
938
939 /* If optlen==0, it is equivalent to val == 0 */
940
941 if (optname == IP_ROUTER_ALERT) {
942 retv = ip_ra_control(sk, val ? 1 : 0, NULL);
943 if (retv == 0)
944 inet_assign_bit(RTALERT, sk, val);
945 return retv;
946 }
947 if (ip_mroute_opt(optname))
948 return ip_mroute_setsockopt(sk, optname, optval, optlen);
949
950 /* Handle options that can be set without locking the socket. */
951 switch (optname) {
952 case IP_PKTINFO:
953 inet_assign_bit(PKTINFO, sk, val);
954 return 0;
955 case IP_RECVTTL:
956 inet_assign_bit(TTL, sk, val);
957 return 0;
958 case IP_RECVTOS:
959 inet_assign_bit(TOS, sk, val);
960 return 0;
961 case IP_RECVOPTS:
962 inet_assign_bit(RECVOPTS, sk, val);
963 return 0;
964 case IP_RETOPTS:
965 inet_assign_bit(RETOPTS, sk, val);
966 return 0;
967 case IP_PASSSEC:
968 inet_assign_bit(PASSSEC, sk, val);
969 return 0;
970 case IP_RECVORIGDSTADDR:
971 inet_assign_bit(ORIGDSTADDR, sk, val);
972 return 0;
973 case IP_RECVFRAGSIZE:
974 if (sk->sk_type != SOCK_RAW && sk->sk_type != SOCK_DGRAM)
975 return -EINVAL;
976 inet_assign_bit(RECVFRAGSIZE, sk, val);
977 return 0;
978 case IP_RECVERR:
979 inet_assign_bit(RECVERR, sk, val);
980 if (!val)
981 skb_errqueue_purge(&sk->sk_error_queue);
982 return 0;
983 case IP_RECVERR_RFC4884:
984 if (val < 0 || val > 1)
985 return -EINVAL;
986 inet_assign_bit(RECVERR_RFC4884, sk, val);
987 return 0;
988 case IP_FREEBIND:
989 if (optlen < 1)
990 return -EINVAL;
991 inet_assign_bit(FREEBIND, sk, val);
992 return 0;
993 case IP_HDRINCL:
994 if (sk->sk_type != SOCK_RAW)
995 return -ENOPROTOOPT;
996 inet_assign_bit(HDRINCL, sk, val);
997 return 0;
998 case IP_MULTICAST_LOOP:
999 if (optlen < 1)
1000 return -EINVAL;
1001 inet_assign_bit(MC_LOOP, sk, val);
1002 return 0;
1003 case IP_MULTICAST_ALL:
1004 if (optlen < 1)
1005 return -EINVAL;
1006 if (val != 0 && val != 1)
1007 return -EINVAL;
1008 inet_assign_bit(MC_ALL, sk, val);
1009 return 0;
1010 case IP_TRANSPARENT:
1011 if (!!val && !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
1012 !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1013 return -EPERM;
1014 if (optlen < 1)
1015 return -EINVAL;
1016 inet_assign_bit(TRANSPARENT, sk, val);
1017 return 0;
1018 case IP_NODEFRAG:
1019 if (sk->sk_type != SOCK_RAW)
1020 return -ENOPROTOOPT;
1021 inet_assign_bit(NODEFRAG, sk, val);
1022 return 0;
1023 case IP_BIND_ADDRESS_NO_PORT:
1024 inet_assign_bit(BIND_ADDRESS_NO_PORT, sk, val);
1025 return 0;
1026 case IP_TTL:
1027 if (optlen < 1)
1028 return -EINVAL;
1029 if (val != -1 && (val < 1 || val > 255))
1030 return -EINVAL;
1031 WRITE_ONCE(inet->uc_ttl, val);
1032 return 0;
1033 case IP_MINTTL:
1034 if (optlen < 1)
1035 return -EINVAL;
1036 if (val < 0 || val > 255)
1037 return -EINVAL;
1038
1039 if (val)
1040 static_branch_enable(&ip4_min_ttl);
1041
1042 WRITE_ONCE(inet->min_ttl, val);
1043 return 0;
1044 case IP_MULTICAST_TTL:
1045 if (sk->sk_type == SOCK_STREAM)
1046 return -EINVAL;
1047 if (optlen < 1)
1048 return -EINVAL;
1049 if (val == -1)
1050 val = 1;
1051 if (val < 0 || val > 255)
1052 return -EINVAL;
1053 WRITE_ONCE(inet->mc_ttl, val);
1054 return 0;
1055 case IP_MTU_DISCOVER:
1056 return ip_sock_set_mtu_discover(sk, val);
1057 case IP_TOS: /* This sets both TOS and Precedence */
1058 ip_sock_set_tos(sk, val);
1059 return 0;
1060 case IP_LOCAL_PORT_RANGE:
1061 {
1062 u16 lo = val;
1063 u16 hi = val >> 16;
1064
1065 if (optlen != sizeof(u32))
1066 return -EINVAL;
1067 if (lo != 0 && hi != 0 && lo > hi)
1068 return -EINVAL;
1069
1070 WRITE_ONCE(inet->local_port_range, val);
1071 return 0;
1072 }
1073 }
1074
1075 err = 0;
1076 if (needs_rtnl)
1077 rtnl_lock();
1078 sockopt_lock_sock(sk);
1079
1080 switch (optname) {
1081 case IP_OPTIONS:
1082 {
1083 struct ip_options_rcu *old, *opt = NULL;
1084
1085 if (optlen > 40)
1086 goto e_inval;
1087 err = ip_options_get(sock_net(sk), &opt, optval, optlen);
1088 if (err)
1089 break;
1090 old = rcu_dereference_protected(inet->inet_opt,
1091 lockdep_sock_is_held(sk));
1092 if (inet_test_bit(IS_ICSK, sk)) {
1093 struct inet_connection_sock *icsk = inet_csk(sk);
1094#if IS_ENABLED(CONFIG_IPV6)
1095 if (sk->sk_family == PF_INET ||
1096 (!((1 << sk->sk_state) &
1097 (TCPF_LISTEN | TCPF_CLOSE)) &&
1098 inet->inet_daddr != LOOPBACK4_IPV6)) {
1099#endif
1100 if (old)
1101 icsk->icsk_ext_hdr_len -= old->opt.optlen;
1102 if (opt)
1103 icsk->icsk_ext_hdr_len += opt->opt.optlen;
1104 icsk->icsk_sync_mss(sk, icsk->icsk_pmtu_cookie);
1105#if IS_ENABLED(CONFIG_IPV6)
1106 }
1107#endif
1108 }
1109 rcu_assign_pointer(inet->inet_opt, opt);
1110 if (old)
1111 kfree_rcu(old, rcu);
1112 break;
1113 }
1114 case IP_CHECKSUM:
1115 if (val) {
1116 if (!(inet_test_bit(CHECKSUM, sk))) {
1117 inet_inc_convert_csum(sk);
1118 inet_set_bit(CHECKSUM, sk);
1119 }
1120 } else {
1121 if (inet_test_bit(CHECKSUM, sk)) {
1122 inet_dec_convert_csum(sk);
1123 inet_clear_bit(CHECKSUM, sk);
1124 }
1125 }
1126 break;
1127 case IP_UNICAST_IF:
1128 {
1129 struct net_device *dev = NULL;
1130 int ifindex;
1131 int midx;
1132
1133 if (optlen != sizeof(int))
1134 goto e_inval;
1135
1136 ifindex = (__force int)ntohl((__force __be32)val);
1137 if (ifindex == 0) {
1138 WRITE_ONCE(inet->uc_index, 0);
1139 err = 0;
1140 break;
1141 }
1142
1143 dev = dev_get_by_index(sock_net(sk), ifindex);
1144 err = -EADDRNOTAVAIL;
1145 if (!dev)
1146 break;
1147
1148 midx = l3mdev_master_ifindex(dev);
1149 dev_put(dev);
1150
1151 err = -EINVAL;
1152 if (sk->sk_bound_dev_if && midx != sk->sk_bound_dev_if)
1153 break;
1154
1155 WRITE_ONCE(inet->uc_index, ifindex);
1156 err = 0;
1157 break;
1158 }
1159 case IP_MULTICAST_IF:
1160 {
1161 struct ip_mreqn mreq;
1162 struct net_device *dev = NULL;
1163 int midx;
1164
1165 if (sk->sk_type == SOCK_STREAM)
1166 goto e_inval;
1167 /*
1168 * Check the arguments are allowable
1169 */
1170
1171 if (optlen < sizeof(struct in_addr))
1172 goto e_inval;
1173
1174 err = -EFAULT;
1175 if (optlen >= sizeof(struct ip_mreqn)) {
1176 if (copy_from_sockptr(&mreq, optval, sizeof(mreq)))
1177 break;
1178 } else {
1179 memset(&mreq, 0, sizeof(mreq));
1180 if (optlen >= sizeof(struct ip_mreq)) {
1181 if (copy_from_sockptr(&mreq, optval,
1182 sizeof(struct ip_mreq)))
1183 break;
1184 } else if (optlen >= sizeof(struct in_addr)) {
1185 if (copy_from_sockptr(&mreq.imr_address, optval,
1186 sizeof(struct in_addr)))
1187 break;
1188 }
1189 }
1190
1191 if (!mreq.imr_ifindex) {
1192 if (mreq.imr_address.s_addr == htonl(INADDR_ANY)) {
1193 WRITE_ONCE(inet->mc_index, 0);
1194 WRITE_ONCE(inet->mc_addr, 0);
1195 err = 0;
1196 break;
1197 }
1198 dev = ip_dev_find(sock_net(sk), mreq.imr_address.s_addr);
1199 if (dev)
1200 mreq.imr_ifindex = dev->ifindex;
1201 } else
1202 dev = dev_get_by_index(sock_net(sk), mreq.imr_ifindex);
1203
1204
1205 err = -EADDRNOTAVAIL;
1206 if (!dev)
1207 break;
1208
1209 midx = l3mdev_master_ifindex(dev);
1210
1211 dev_put(dev);
1212
1213 err = -EINVAL;
1214 if (sk->sk_bound_dev_if &&
1215 mreq.imr_ifindex != sk->sk_bound_dev_if &&
1216 midx != sk->sk_bound_dev_if)
1217 break;
1218
1219 WRITE_ONCE(inet->mc_index, mreq.imr_ifindex);
1220 WRITE_ONCE(inet->mc_addr, mreq.imr_address.s_addr);
1221 err = 0;
1222 break;
1223 }
1224
1225 case IP_ADD_MEMBERSHIP:
1226 case IP_DROP_MEMBERSHIP:
1227 {
1228 struct ip_mreqn mreq;
1229
1230 err = -EPROTO;
1231 if (inet_test_bit(IS_ICSK, sk))
1232 break;
1233
1234 if (optlen < sizeof(struct ip_mreq))
1235 goto e_inval;
1236 err = -EFAULT;
1237 if (optlen >= sizeof(struct ip_mreqn)) {
1238 if (copy_from_sockptr(&mreq, optval, sizeof(mreq)))
1239 break;
1240 } else {
1241 memset(&mreq, 0, sizeof(mreq));
1242 if (copy_from_sockptr(&mreq, optval,
1243 sizeof(struct ip_mreq)))
1244 break;
1245 }
1246
1247 if (optname == IP_ADD_MEMBERSHIP)
1248 err = ip_mc_join_group(sk, &mreq);
1249 else
1250 err = ip_mc_leave_group(sk, &mreq);
1251 break;
1252 }
1253 case IP_MSFILTER:
1254 {
1255 struct ip_msfilter *msf;
1256
1257 if (optlen < IP_MSFILTER_SIZE(0))
1258 goto e_inval;
1259 if (optlen > READ_ONCE(net->core.sysctl_optmem_max)) {
1260 err = -ENOBUFS;
1261 break;
1262 }
1263 msf = memdup_sockptr(optval, optlen);
1264 if (IS_ERR(msf)) {
1265 err = PTR_ERR(msf);
1266 break;
1267 }
1268 /* numsrc >= (1G-4) overflow in 32 bits */
1269 if (msf->imsf_numsrc >= 0x3ffffffcU ||
1270 msf->imsf_numsrc > READ_ONCE(net->ipv4.sysctl_igmp_max_msf)) {
1271 kfree(msf);
1272 err = -ENOBUFS;
1273 break;
1274 }
1275 if (IP_MSFILTER_SIZE(msf->imsf_numsrc) > optlen) {
1276 kfree(msf);
1277 err = -EINVAL;
1278 break;
1279 }
1280 err = ip_mc_msfilter(sk, msf, 0);
1281 kfree(msf);
1282 break;
1283 }
1284 case IP_BLOCK_SOURCE:
1285 case IP_UNBLOCK_SOURCE:
1286 case IP_ADD_SOURCE_MEMBERSHIP:
1287 case IP_DROP_SOURCE_MEMBERSHIP:
1288 {
1289 struct ip_mreq_source mreqs;
1290 int omode, add;
1291
1292 if (optlen != sizeof(struct ip_mreq_source))
1293 goto e_inval;
1294 if (copy_from_sockptr(&mreqs, optval, sizeof(mreqs))) {
1295 err = -EFAULT;
1296 break;
1297 }
1298 if (optname == IP_BLOCK_SOURCE) {
1299 omode = MCAST_EXCLUDE;
1300 add = 1;
1301 } else if (optname == IP_UNBLOCK_SOURCE) {
1302 omode = MCAST_EXCLUDE;
1303 add = 0;
1304 } else if (optname == IP_ADD_SOURCE_MEMBERSHIP) {
1305 struct ip_mreqn mreq;
1306
1307 mreq.imr_multiaddr.s_addr = mreqs.imr_multiaddr;
1308 mreq.imr_address.s_addr = mreqs.imr_interface;
1309 mreq.imr_ifindex = 0;
1310 err = ip_mc_join_group_ssm(sk, &mreq, MCAST_INCLUDE);
1311 if (err && err != -EADDRINUSE)
1312 break;
1313 omode = MCAST_INCLUDE;
1314 add = 1;
1315 } else /* IP_DROP_SOURCE_MEMBERSHIP */ {
1316 omode = MCAST_INCLUDE;
1317 add = 0;
1318 }
1319 err = ip_mc_source(add, omode, sk, &mreqs, 0);
1320 break;
1321 }
1322 case MCAST_JOIN_GROUP:
1323 case MCAST_LEAVE_GROUP:
1324 if (in_compat_syscall())
1325 err = compat_ip_mcast_join_leave(sk, optname, optval,
1326 optlen);
1327 else
1328 err = ip_mcast_join_leave(sk, optname, optval, optlen);
1329 break;
1330 case MCAST_JOIN_SOURCE_GROUP:
1331 case MCAST_LEAVE_SOURCE_GROUP:
1332 case MCAST_BLOCK_SOURCE:
1333 case MCAST_UNBLOCK_SOURCE:
1334 err = do_mcast_group_source(sk, optname, optval, optlen);
1335 break;
1336 case MCAST_MSFILTER:
1337 if (in_compat_syscall())
1338 err = compat_ip_set_mcast_msfilter(sk, optval, optlen);
1339 else
1340 err = ip_set_mcast_msfilter(sk, optval, optlen);
1341 break;
1342 case IP_IPSEC_POLICY:
1343 case IP_XFRM_POLICY:
1344 err = -EPERM;
1345 if (!sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1346 break;
1347 err = xfrm_user_policy(sk, optname, optval, optlen);
1348 break;
1349
1350 default:
1351 err = -ENOPROTOOPT;
1352 break;
1353 }
1354 sockopt_release_sock(sk);
1355 if (needs_rtnl)
1356 rtnl_unlock();
1357 return err;
1358
1359e_inval:
1360 sockopt_release_sock(sk);
1361 if (needs_rtnl)
1362 rtnl_unlock();
1363 return -EINVAL;
1364}
1365
1366/**
1367 * ipv4_pktinfo_prepare - transfer some info from rtable to skb
1368 * @sk: socket
1369 * @skb: buffer
1370 * @drop_dst: if true, drops skb dst
1371 *
1372 * To support IP_CMSG_PKTINFO option, we store rt_iif and specific
1373 * destination in skb->cb[] before dst drop.
1374 * This way, receiver doesn't make cache line misses to read rtable.
1375 */
1376void ipv4_pktinfo_prepare(const struct sock *sk, struct sk_buff *skb, bool drop_dst)
1377{
1378 struct in_pktinfo *pktinfo = PKTINFO_SKB_CB(skb);
1379 bool prepare = inet_test_bit(PKTINFO, sk) ||
1380 ipv6_sk_rxinfo(sk);
1381
1382 if (prepare && skb_rtable(skb)) {
1383 /* skb->cb is overloaded: prior to this point it is IP{6}CB
1384 * which has interface index (iif) as the first member of the
1385 * underlying inet{6}_skb_parm struct. This code then overlays
1386 * PKTINFO_SKB_CB and in_pktinfo also has iif as the first
1387 * element so the iif is picked up from the prior IPCB. If iif
1388 * is the loopback interface, then return the sending interface
1389 * (e.g., process binds socket to eth0 for Tx which is
1390 * redirected to loopback in the rtable/dst).
1391 */
1392 struct rtable *rt = skb_rtable(skb);
1393 bool l3slave = ipv4_l3mdev_skb(IPCB(skb)->flags);
1394
1395 if (pktinfo->ipi_ifindex == LOOPBACK_IFINDEX)
1396 pktinfo->ipi_ifindex = inet_iif(skb);
1397 else if (l3slave && rt && rt->rt_iif)
1398 pktinfo->ipi_ifindex = rt->rt_iif;
1399
1400 pktinfo->ipi_spec_dst.s_addr = fib_compute_spec_dst(skb);
1401 } else {
1402 pktinfo->ipi_ifindex = 0;
1403 pktinfo->ipi_spec_dst.s_addr = 0;
1404 }
1405 if (drop_dst)
1406 skb_dst_drop(skb);
1407}
1408
1409int ip_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
1410 unsigned int optlen)
1411{
1412 int err;
1413
1414 if (level != SOL_IP)
1415 return -ENOPROTOOPT;
1416
1417 err = do_ip_setsockopt(sk, level, optname, optval, optlen);
1418#ifdef CONFIG_NETFILTER
1419 /* we need to exclude all possible ENOPROTOOPTs except default case */
1420 if (err == -ENOPROTOOPT && optname != IP_HDRINCL &&
1421 optname != IP_IPSEC_POLICY &&
1422 optname != IP_XFRM_POLICY &&
1423 !ip_mroute_opt(optname))
1424 err = nf_setsockopt(sk, PF_INET, optname, optval, optlen);
1425#endif
1426 return err;
1427}
1428EXPORT_SYMBOL(ip_setsockopt);
1429
1430/*
1431 * Get the options. Note for future reference. The GET of IP options gets
1432 * the _received_ ones. The set sets the _sent_ ones.
1433 */
1434
1435static bool getsockopt_needs_rtnl(int optname)
1436{
1437 switch (optname) {
1438 case IP_MSFILTER:
1439 case MCAST_MSFILTER:
1440 return true;
1441 }
1442 return false;
1443}
1444
1445static int ip_get_mcast_msfilter(struct sock *sk, sockptr_t optval,
1446 sockptr_t optlen, int len)
1447{
1448 const int size0 = offsetof(struct group_filter, gf_slist_flex);
1449 struct group_filter gsf;
1450 int num, gsf_size;
1451 int err;
1452
1453 if (len < size0)
1454 return -EINVAL;
1455 if (copy_from_sockptr(&gsf, optval, size0))
1456 return -EFAULT;
1457
1458 num = gsf.gf_numsrc;
1459 err = ip_mc_gsfget(sk, &gsf, optval,
1460 offsetof(struct group_filter, gf_slist_flex));
1461 if (err)
1462 return err;
1463 if (gsf.gf_numsrc < num)
1464 num = gsf.gf_numsrc;
1465 gsf_size = GROUP_FILTER_SIZE(num);
1466 if (copy_to_sockptr(optlen, &gsf_size, sizeof(int)) ||
1467 copy_to_sockptr(optval, &gsf, size0))
1468 return -EFAULT;
1469 return 0;
1470}
1471
1472static int compat_ip_get_mcast_msfilter(struct sock *sk, sockptr_t optval,
1473 sockptr_t optlen, int len)
1474{
1475 const int size0 = offsetof(struct compat_group_filter, gf_slist_flex);
1476 struct compat_group_filter gf32;
1477 struct group_filter gf;
1478 int num;
1479 int err;
1480
1481 if (len < size0)
1482 return -EINVAL;
1483 if (copy_from_sockptr(&gf32, optval, size0))
1484 return -EFAULT;
1485
1486 gf.gf_interface = gf32.gf_interface;
1487 gf.gf_fmode = gf32.gf_fmode;
1488 num = gf.gf_numsrc = gf32.gf_numsrc;
1489 gf.gf_group = gf32.gf_group;
1490
1491 err = ip_mc_gsfget(sk, &gf, optval,
1492 offsetof(struct compat_group_filter, gf_slist_flex));
1493 if (err)
1494 return err;
1495 if (gf.gf_numsrc < num)
1496 num = gf.gf_numsrc;
1497 len = GROUP_FILTER_SIZE(num) - (sizeof(gf) - sizeof(gf32));
1498 if (copy_to_sockptr(optlen, &len, sizeof(int)) ||
1499 copy_to_sockptr_offset(optval, offsetof(struct compat_group_filter, gf_fmode),
1500 &gf.gf_fmode, sizeof(gf.gf_fmode)) ||
1501 copy_to_sockptr_offset(optval, offsetof(struct compat_group_filter, gf_numsrc),
1502 &gf.gf_numsrc, sizeof(gf.gf_numsrc)))
1503 return -EFAULT;
1504 return 0;
1505}
1506
1507int do_ip_getsockopt(struct sock *sk, int level, int optname,
1508 sockptr_t optval, sockptr_t optlen)
1509{
1510 struct inet_sock *inet = inet_sk(sk);
1511 bool needs_rtnl = getsockopt_needs_rtnl(optname);
1512 int val, err = 0;
1513 int len;
1514
1515 if (level != SOL_IP)
1516 return -EOPNOTSUPP;
1517
1518 if (ip_mroute_opt(optname))
1519 return ip_mroute_getsockopt(sk, optname, optval, optlen);
1520
1521 if (copy_from_sockptr(&len, optlen, sizeof(int)))
1522 return -EFAULT;
1523 if (len < 0)
1524 return -EINVAL;
1525
1526 /* Handle options that can be read without locking the socket. */
1527 switch (optname) {
1528 case IP_PKTINFO:
1529 val = inet_test_bit(PKTINFO, sk);
1530 goto copyval;
1531 case IP_RECVTTL:
1532 val = inet_test_bit(TTL, sk);
1533 goto copyval;
1534 case IP_RECVTOS:
1535 val = inet_test_bit(TOS, sk);
1536 goto copyval;
1537 case IP_RECVOPTS:
1538 val = inet_test_bit(RECVOPTS, sk);
1539 goto copyval;
1540 case IP_RETOPTS:
1541 val = inet_test_bit(RETOPTS, sk);
1542 goto copyval;
1543 case IP_PASSSEC:
1544 val = inet_test_bit(PASSSEC, sk);
1545 goto copyval;
1546 case IP_RECVORIGDSTADDR:
1547 val = inet_test_bit(ORIGDSTADDR, sk);
1548 goto copyval;
1549 case IP_CHECKSUM:
1550 val = inet_test_bit(CHECKSUM, sk);
1551 goto copyval;
1552 case IP_RECVFRAGSIZE:
1553 val = inet_test_bit(RECVFRAGSIZE, sk);
1554 goto copyval;
1555 case IP_RECVERR:
1556 val = inet_test_bit(RECVERR, sk);
1557 goto copyval;
1558 case IP_RECVERR_RFC4884:
1559 val = inet_test_bit(RECVERR_RFC4884, sk);
1560 goto copyval;
1561 case IP_FREEBIND:
1562 val = inet_test_bit(FREEBIND, sk);
1563 goto copyval;
1564 case IP_HDRINCL:
1565 val = inet_test_bit(HDRINCL, sk);
1566 goto copyval;
1567 case IP_MULTICAST_LOOP:
1568 val = inet_test_bit(MC_LOOP, sk);
1569 goto copyval;
1570 case IP_MULTICAST_ALL:
1571 val = inet_test_bit(MC_ALL, sk);
1572 goto copyval;
1573 case IP_TRANSPARENT:
1574 val = inet_test_bit(TRANSPARENT, sk);
1575 goto copyval;
1576 case IP_NODEFRAG:
1577 val = inet_test_bit(NODEFRAG, sk);
1578 goto copyval;
1579 case IP_BIND_ADDRESS_NO_PORT:
1580 val = inet_test_bit(BIND_ADDRESS_NO_PORT, sk);
1581 goto copyval;
1582 case IP_ROUTER_ALERT:
1583 val = inet_test_bit(RTALERT, sk);
1584 goto copyval;
1585 case IP_TTL:
1586 val = READ_ONCE(inet->uc_ttl);
1587 if (val < 0)
1588 val = READ_ONCE(sock_net(sk)->ipv4.sysctl_ip_default_ttl);
1589 goto copyval;
1590 case IP_MINTTL:
1591 val = READ_ONCE(inet->min_ttl);
1592 goto copyval;
1593 case IP_MULTICAST_TTL:
1594 val = READ_ONCE(inet->mc_ttl);
1595 goto copyval;
1596 case IP_MTU_DISCOVER:
1597 val = READ_ONCE(inet->pmtudisc);
1598 goto copyval;
1599 case IP_TOS:
1600 val = READ_ONCE(inet->tos);
1601 goto copyval;
1602 case IP_OPTIONS:
1603 {
1604 unsigned char optbuf[sizeof(struct ip_options)+40];
1605 struct ip_options *opt = (struct ip_options *)optbuf;
1606 struct ip_options_rcu *inet_opt;
1607
1608 rcu_read_lock();
1609 inet_opt = rcu_dereference(inet->inet_opt);
1610 opt->optlen = 0;
1611 if (inet_opt)
1612 memcpy(optbuf, &inet_opt->opt,
1613 sizeof(struct ip_options) +
1614 inet_opt->opt.optlen);
1615 rcu_read_unlock();
1616
1617 if (opt->optlen == 0) {
1618 len = 0;
1619 return copy_to_sockptr(optlen, &len, sizeof(int));
1620 }
1621
1622 ip_options_undo(opt);
1623
1624 len = min_t(unsigned int, len, opt->optlen);
1625 if (copy_to_sockptr(optlen, &len, sizeof(int)))
1626 return -EFAULT;
1627 if (copy_to_sockptr(optval, opt->__data, len))
1628 return -EFAULT;
1629 return 0;
1630 }
1631 case IP_MTU:
1632 {
1633 struct dst_entry *dst;
1634 val = 0;
1635 dst = sk_dst_get(sk);
1636 if (dst) {
1637 val = dst_mtu(dst);
1638 dst_release(dst);
1639 }
1640 if (!val)
1641 return -ENOTCONN;
1642 goto copyval;
1643 }
1644 case IP_PKTOPTIONS:
1645 {
1646 struct msghdr msg;
1647
1648 if (sk->sk_type != SOCK_STREAM)
1649 return -ENOPROTOOPT;
1650
1651 if (optval.is_kernel) {
1652 msg.msg_control_is_user = false;
1653 msg.msg_control = optval.kernel;
1654 } else {
1655 msg.msg_control_is_user = true;
1656 msg.msg_control_user = optval.user;
1657 }
1658 msg.msg_controllen = len;
1659 msg.msg_flags = in_compat_syscall() ? MSG_CMSG_COMPAT : 0;
1660
1661 if (inet_test_bit(PKTINFO, sk)) {
1662 struct in_pktinfo info;
1663
1664 info.ipi_addr.s_addr = READ_ONCE(inet->inet_rcv_saddr);
1665 info.ipi_spec_dst.s_addr = READ_ONCE(inet->inet_rcv_saddr);
1666 info.ipi_ifindex = READ_ONCE(inet->mc_index);
1667 put_cmsg(&msg, SOL_IP, IP_PKTINFO, sizeof(info), &info);
1668 }
1669 if (inet_test_bit(TTL, sk)) {
1670 int hlim = READ_ONCE(inet->mc_ttl);
1671
1672 put_cmsg(&msg, SOL_IP, IP_TTL, sizeof(hlim), &hlim);
1673 }
1674 if (inet_test_bit(TOS, sk)) {
1675 int tos = READ_ONCE(inet->rcv_tos);
1676 put_cmsg(&msg, SOL_IP, IP_TOS, sizeof(tos), &tos);
1677 }
1678 len -= msg.msg_controllen;
1679 return copy_to_sockptr(optlen, &len, sizeof(int));
1680 }
1681 case IP_UNICAST_IF:
1682 val = (__force int)htonl((__u32) READ_ONCE(inet->uc_index));
1683 goto copyval;
1684 case IP_MULTICAST_IF:
1685 {
1686 struct in_addr addr;
1687 len = min_t(unsigned int, len, sizeof(struct in_addr));
1688 addr.s_addr = READ_ONCE(inet->mc_addr);
1689
1690 if (copy_to_sockptr(optlen, &len, sizeof(int)))
1691 return -EFAULT;
1692 if (copy_to_sockptr(optval, &addr, len))
1693 return -EFAULT;
1694 return 0;
1695 }
1696 case IP_LOCAL_PORT_RANGE:
1697 val = READ_ONCE(inet->local_port_range);
1698 goto copyval;
1699 }
1700
1701 if (needs_rtnl)
1702 rtnl_lock();
1703 sockopt_lock_sock(sk);
1704
1705 switch (optname) {
1706 case IP_MSFILTER:
1707 {
1708 struct ip_msfilter msf;
1709
1710 if (len < IP_MSFILTER_SIZE(0)) {
1711 err = -EINVAL;
1712 goto out;
1713 }
1714 if (copy_from_sockptr(&msf, optval, IP_MSFILTER_SIZE(0))) {
1715 err = -EFAULT;
1716 goto out;
1717 }
1718 err = ip_mc_msfget(sk, &msf, optval, optlen);
1719 goto out;
1720 }
1721 case MCAST_MSFILTER:
1722 if (in_compat_syscall())
1723 err = compat_ip_get_mcast_msfilter(sk, optval, optlen,
1724 len);
1725 else
1726 err = ip_get_mcast_msfilter(sk, optval, optlen, len);
1727 goto out;
1728 case IP_PROTOCOL:
1729 val = inet_sk(sk)->inet_num;
1730 break;
1731 default:
1732 sockopt_release_sock(sk);
1733 return -ENOPROTOOPT;
1734 }
1735 sockopt_release_sock(sk);
1736copyval:
1737 if (len < sizeof(int) && len > 0 && val >= 0 && val <= 255) {
1738 unsigned char ucval = (unsigned char)val;
1739 len = 1;
1740 if (copy_to_sockptr(optlen, &len, sizeof(int)))
1741 return -EFAULT;
1742 if (copy_to_sockptr(optval, &ucval, 1))
1743 return -EFAULT;
1744 } else {
1745 len = min_t(unsigned int, sizeof(int), len);
1746 if (copy_to_sockptr(optlen, &len, sizeof(int)))
1747 return -EFAULT;
1748 if (copy_to_sockptr(optval, &val, len))
1749 return -EFAULT;
1750 }
1751 return 0;
1752
1753out:
1754 sockopt_release_sock(sk);
1755 if (needs_rtnl)
1756 rtnl_unlock();
1757 return err;
1758}
1759
1760int ip_getsockopt(struct sock *sk, int level,
1761 int optname, char __user *optval, int __user *optlen)
1762{
1763 int err;
1764
1765 err = do_ip_getsockopt(sk, level, optname,
1766 USER_SOCKPTR(optval), USER_SOCKPTR(optlen));
1767
1768#ifdef CONFIG_NETFILTER
1769 /* we need to exclude all possible ENOPROTOOPTs except default case */
1770 if (err == -ENOPROTOOPT && optname != IP_PKTOPTIONS &&
1771 !ip_mroute_opt(optname)) {
1772 int len;
1773
1774 if (get_user(len, optlen))
1775 return -EFAULT;
1776
1777 err = nf_getsockopt(sk, PF_INET, optname, optval, &len);
1778 if (err >= 0)
1779 err = put_user(len, optlen);
1780 return err;
1781 }
1782#endif
1783 return err;
1784}
1785EXPORT_SYMBOL(ip_getsockopt);