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
ip_cmsg_recv_pktinfo(struct msghdr * msg,struct sk_buff * skb)53 static 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
ip_cmsg_recv_ttl(struct msghdr * msg,struct sk_buff * skb)62 static 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
ip_cmsg_recv_tos(struct msghdr * msg,struct sk_buff * skb)68 static 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
ip_cmsg_recv_opts(struct msghdr * msg,struct sk_buff * skb)73 static 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
ip_cmsg_recv_retopts(struct msghdr * msg,struct sk_buff * skb)83 static 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
ip_cmsg_recv_checksum(struct msghdr * msg,struct sk_buff * skb,int offset)100 static 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
ip_cmsg_recv_security(struct msghdr * msg,struct sk_buff * skb)114 static 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
ip_cmsg_recv_dstaddr(struct msghdr * msg,struct sk_buff * skb)132 static 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
ip_cmsg_recv_offset(struct msghdr * msg,struct sk_buff * skb,int offset)154 void 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 }
220 EXPORT_SYMBOL(ip_cmsg_recv_offset);
221
ip_cmsg_send(struct net * net,struct msghdr * msg,struct ipcm_cookie * ipc,bool allow_ipv6)222 int 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 */
305 struct ip_ra_chain __rcu *ip_ra_chain;
306 static DEFINE_SPINLOCK(ip_ra_lock);
307
308
ip_ra_destroy_rcu(struct rcu_head * head)309 static 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
ip_ra_control(struct sock * sk,unsigned char on,void (* destructor)(struct sock *))317 int 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
ip_icmp_error(struct sock * sk,struct sk_buff * skb,int err,__be16 port,u32 info,u8 * payload)371 void 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
ip_local_error(struct sock * sk,int err,__be32 daddr,__be16 port,u32 info)400 void 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 */
ipv4_datagram_support_addr(struct sock_exterr_skb * serr)440 static 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 */
ipv4_datagram_support_cmsg(const struct sock * sk,struct sk_buff * skb,int ee_origin)451 static 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 */
ip_recv_error(struct sock * sk,struct msghdr * msg,int len,int * addr_len)480 int 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
539 out_free_skb:
540 kfree_skb(skb);
541 out:
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 */
setsockopt_needs_rtnl(int optname)550 static 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
do_ip_setsockopt(struct sock * sk,int level,int optname,char __user * optval,unsigned int optlen)572 static 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 int val = 0, err;
577 bool needs_rtnl = setsockopt_needs_rtnl(optname);
578
579 switch (optname) {
580 case IP_PKTINFO:
581 case IP_RECVTTL:
582 case IP_RECVOPTS:
583 case IP_RECVTOS:
584 case IP_RETOPTS:
585 case IP_TOS:
586 case IP_TTL:
587 case IP_HDRINCL:
588 case IP_MTU_DISCOVER:
589 case IP_RECVERR:
590 case IP_ROUTER_ALERT:
591 case IP_FREEBIND:
592 case IP_PASSSEC:
593 case IP_TRANSPARENT:
594 case IP_MINTTL:
595 case IP_NODEFRAG:
596 case IP_UNICAST_IF:
597 case IP_MULTICAST_TTL:
598 case IP_MULTICAST_ALL:
599 case IP_MULTICAST_LOOP:
600 case IP_RECVORIGDSTADDR:
601 case IP_CHECKSUM:
602 if (optlen >= sizeof(int)) {
603 if (get_user(val, (int __user *) optval))
604 return -EFAULT;
605 } else if (optlen >= sizeof(char)) {
606 unsigned char ucval;
607
608 if (get_user(ucval, (unsigned char __user *) optval))
609 return -EFAULT;
610 val = (int) ucval;
611 }
612 }
613
614 /* If optlen==0, it is equivalent to val == 0 */
615
616 if (ip_mroute_opt(optname))
617 return ip_mroute_setsockopt(sk, optname, optval, optlen);
618
619 err = 0;
620 if (needs_rtnl)
621 rtnl_lock();
622 lock_sock(sk);
623
624 switch (optname) {
625 case IP_OPTIONS:
626 {
627 struct ip_options_rcu *old, *opt = NULL;
628
629 if (optlen > 40)
630 goto e_inval;
631 err = ip_options_get_from_user(sock_net(sk), &opt,
632 optval, optlen);
633 if (err)
634 break;
635 old = rcu_dereference_protected(inet->inet_opt,
636 sock_owned_by_user(sk));
637 if (inet->is_icsk) {
638 struct inet_connection_sock *icsk = inet_csk(sk);
639 #if IS_ENABLED(CONFIG_IPV6)
640 if (sk->sk_family == PF_INET ||
641 (!((1 << sk->sk_state) &
642 (TCPF_LISTEN | TCPF_CLOSE)) &&
643 inet->inet_daddr != LOOPBACK4_IPV6)) {
644 #endif
645 if (old)
646 icsk->icsk_ext_hdr_len -= old->opt.optlen;
647 if (opt)
648 icsk->icsk_ext_hdr_len += opt->opt.optlen;
649 icsk->icsk_sync_mss(sk, icsk->icsk_pmtu_cookie);
650 #if IS_ENABLED(CONFIG_IPV6)
651 }
652 #endif
653 }
654 rcu_assign_pointer(inet->inet_opt, opt);
655 if (old)
656 kfree_rcu(old, rcu);
657 break;
658 }
659 case IP_PKTINFO:
660 if (val)
661 inet->cmsg_flags |= IP_CMSG_PKTINFO;
662 else
663 inet->cmsg_flags &= ~IP_CMSG_PKTINFO;
664 break;
665 case IP_RECVTTL:
666 if (val)
667 inet->cmsg_flags |= IP_CMSG_TTL;
668 else
669 inet->cmsg_flags &= ~IP_CMSG_TTL;
670 break;
671 case IP_RECVTOS:
672 if (val)
673 inet->cmsg_flags |= IP_CMSG_TOS;
674 else
675 inet->cmsg_flags &= ~IP_CMSG_TOS;
676 break;
677 case IP_RECVOPTS:
678 if (val)
679 inet->cmsg_flags |= IP_CMSG_RECVOPTS;
680 else
681 inet->cmsg_flags &= ~IP_CMSG_RECVOPTS;
682 break;
683 case IP_RETOPTS:
684 if (val)
685 inet->cmsg_flags |= IP_CMSG_RETOPTS;
686 else
687 inet->cmsg_flags &= ~IP_CMSG_RETOPTS;
688 break;
689 case IP_PASSSEC:
690 if (val)
691 inet->cmsg_flags |= IP_CMSG_PASSSEC;
692 else
693 inet->cmsg_flags &= ~IP_CMSG_PASSSEC;
694 break;
695 case IP_RECVORIGDSTADDR:
696 if (val)
697 inet->cmsg_flags |= IP_CMSG_ORIGDSTADDR;
698 else
699 inet->cmsg_flags &= ~IP_CMSG_ORIGDSTADDR;
700 break;
701 case IP_CHECKSUM:
702 if (val) {
703 if (!(inet->cmsg_flags & IP_CMSG_CHECKSUM)) {
704 inet_inc_convert_csum(sk);
705 inet->cmsg_flags |= IP_CMSG_CHECKSUM;
706 }
707 } else {
708 if (inet->cmsg_flags & IP_CMSG_CHECKSUM) {
709 inet_dec_convert_csum(sk);
710 inet->cmsg_flags &= ~IP_CMSG_CHECKSUM;
711 }
712 }
713 break;
714 case IP_TOS: /* This sets both TOS and Precedence */
715 if (sk->sk_type == SOCK_STREAM) {
716 val &= ~INET_ECN_MASK;
717 val |= inet->tos & INET_ECN_MASK;
718 }
719 if (inet->tos != val) {
720 inet->tos = val;
721 sk->sk_priority = rt_tos2priority(val);
722 sk_dst_reset(sk);
723 }
724 break;
725 case IP_TTL:
726 if (optlen < 1)
727 goto e_inval;
728 if (val != -1 && (val < 1 || val > 255))
729 goto e_inval;
730 inet->uc_ttl = val;
731 break;
732 case IP_HDRINCL:
733 if (sk->sk_type != SOCK_RAW) {
734 err = -ENOPROTOOPT;
735 break;
736 }
737 inet->hdrincl = val ? 1 : 0;
738 break;
739 case IP_NODEFRAG:
740 if (sk->sk_type != SOCK_RAW) {
741 err = -ENOPROTOOPT;
742 break;
743 }
744 inet->nodefrag = val ? 1 : 0;
745 break;
746 case IP_MTU_DISCOVER:
747 if (val < IP_PMTUDISC_DONT || val > IP_PMTUDISC_OMIT)
748 goto e_inval;
749 inet->pmtudisc = val;
750 break;
751 case IP_RECVERR:
752 inet->recverr = !!val;
753 if (!val)
754 skb_queue_purge(&sk->sk_error_queue);
755 break;
756 case IP_MULTICAST_TTL:
757 if (sk->sk_type == SOCK_STREAM)
758 goto e_inval;
759 if (optlen < 1)
760 goto e_inval;
761 if (val == -1)
762 val = 1;
763 if (val < 0 || val > 255)
764 goto e_inval;
765 inet->mc_ttl = val;
766 break;
767 case IP_MULTICAST_LOOP:
768 if (optlen < 1)
769 goto e_inval;
770 inet->mc_loop = !!val;
771 break;
772 case IP_UNICAST_IF:
773 {
774 struct net_device *dev = NULL;
775 int ifindex;
776
777 if (optlen != sizeof(int))
778 goto e_inval;
779
780 ifindex = (__force int)ntohl((__force __be32)val);
781 if (ifindex == 0) {
782 inet->uc_index = 0;
783 err = 0;
784 break;
785 }
786
787 dev = dev_get_by_index(sock_net(sk), ifindex);
788 err = -EADDRNOTAVAIL;
789 if (!dev)
790 break;
791 dev_put(dev);
792
793 err = -EINVAL;
794 if (sk->sk_bound_dev_if)
795 break;
796
797 inet->uc_index = ifindex;
798 err = 0;
799 break;
800 }
801 case IP_MULTICAST_IF:
802 {
803 struct ip_mreqn mreq;
804 struct net_device *dev = NULL;
805
806 if (sk->sk_type == SOCK_STREAM)
807 goto e_inval;
808 /*
809 * Check the arguments are allowable
810 */
811
812 if (optlen < sizeof(struct in_addr))
813 goto e_inval;
814
815 err = -EFAULT;
816 if (optlen >= sizeof(struct ip_mreqn)) {
817 if (copy_from_user(&mreq, optval, sizeof(mreq)))
818 break;
819 } else {
820 memset(&mreq, 0, sizeof(mreq));
821 if (optlen >= sizeof(struct ip_mreq)) {
822 if (copy_from_user(&mreq, optval,
823 sizeof(struct ip_mreq)))
824 break;
825 } else if (optlen >= sizeof(struct in_addr)) {
826 if (copy_from_user(&mreq.imr_address, optval,
827 sizeof(struct in_addr)))
828 break;
829 }
830 }
831
832 if (!mreq.imr_ifindex) {
833 if (mreq.imr_address.s_addr == htonl(INADDR_ANY)) {
834 inet->mc_index = 0;
835 inet->mc_addr = 0;
836 err = 0;
837 break;
838 }
839 dev = ip_dev_find(sock_net(sk), mreq.imr_address.s_addr);
840 if (dev)
841 mreq.imr_ifindex = dev->ifindex;
842 } else
843 dev = dev_get_by_index(sock_net(sk), mreq.imr_ifindex);
844
845
846 err = -EADDRNOTAVAIL;
847 if (!dev)
848 break;
849 dev_put(dev);
850
851 err = -EINVAL;
852 if (sk->sk_bound_dev_if &&
853 mreq.imr_ifindex != sk->sk_bound_dev_if)
854 break;
855
856 inet->mc_index = mreq.imr_ifindex;
857 inet->mc_addr = mreq.imr_address.s_addr;
858 err = 0;
859 break;
860 }
861
862 case IP_ADD_MEMBERSHIP:
863 case IP_DROP_MEMBERSHIP:
864 {
865 struct ip_mreqn mreq;
866
867 err = -EPROTO;
868 if (inet_sk(sk)->is_icsk)
869 break;
870
871 if (optlen < sizeof(struct ip_mreq))
872 goto e_inval;
873 err = -EFAULT;
874 if (optlen >= sizeof(struct ip_mreqn)) {
875 if (copy_from_user(&mreq, optval, sizeof(mreq)))
876 break;
877 } else {
878 memset(&mreq, 0, sizeof(mreq));
879 if (copy_from_user(&mreq, optval, sizeof(struct ip_mreq)))
880 break;
881 }
882
883 if (optname == IP_ADD_MEMBERSHIP)
884 err = ip_mc_join_group(sk, &mreq);
885 else
886 err = ip_mc_leave_group(sk, &mreq);
887 break;
888 }
889 case IP_MSFILTER:
890 {
891 struct ip_msfilter *msf;
892
893 if (optlen < IP_MSFILTER_SIZE(0))
894 goto e_inval;
895 if (optlen > sysctl_optmem_max) {
896 err = -ENOBUFS;
897 break;
898 }
899 msf = kmalloc(optlen, GFP_KERNEL);
900 if (!msf) {
901 err = -ENOBUFS;
902 break;
903 }
904 err = -EFAULT;
905 if (copy_from_user(msf, optval, optlen)) {
906 kfree(msf);
907 break;
908 }
909 /* numsrc >= (1G-4) overflow in 32 bits */
910 if (msf->imsf_numsrc >= 0x3ffffffcU ||
911 msf->imsf_numsrc > sysctl_igmp_max_msf) {
912 kfree(msf);
913 err = -ENOBUFS;
914 break;
915 }
916 if (IP_MSFILTER_SIZE(msf->imsf_numsrc) > optlen) {
917 kfree(msf);
918 err = -EINVAL;
919 break;
920 }
921 err = ip_mc_msfilter(sk, msf, 0);
922 kfree(msf);
923 break;
924 }
925 case IP_BLOCK_SOURCE:
926 case IP_UNBLOCK_SOURCE:
927 case IP_ADD_SOURCE_MEMBERSHIP:
928 case IP_DROP_SOURCE_MEMBERSHIP:
929 {
930 struct ip_mreq_source mreqs;
931 int omode, add;
932
933 if (optlen != sizeof(struct ip_mreq_source))
934 goto e_inval;
935 if (copy_from_user(&mreqs, optval, sizeof(mreqs))) {
936 err = -EFAULT;
937 break;
938 }
939 if (optname == IP_BLOCK_SOURCE) {
940 omode = MCAST_EXCLUDE;
941 add = 1;
942 } else if (optname == IP_UNBLOCK_SOURCE) {
943 omode = MCAST_EXCLUDE;
944 add = 0;
945 } else if (optname == IP_ADD_SOURCE_MEMBERSHIP) {
946 struct ip_mreqn mreq;
947
948 mreq.imr_multiaddr.s_addr = mreqs.imr_multiaddr;
949 mreq.imr_address.s_addr = mreqs.imr_interface;
950 mreq.imr_ifindex = 0;
951 err = ip_mc_join_group(sk, &mreq);
952 if (err && err != -EADDRINUSE)
953 break;
954 omode = MCAST_INCLUDE;
955 add = 1;
956 } else /* IP_DROP_SOURCE_MEMBERSHIP */ {
957 omode = MCAST_INCLUDE;
958 add = 0;
959 }
960 err = ip_mc_source(add, omode, sk, &mreqs, 0);
961 break;
962 }
963 case MCAST_JOIN_GROUP:
964 case MCAST_LEAVE_GROUP:
965 {
966 struct group_req greq;
967 struct sockaddr_in *psin;
968 struct ip_mreqn mreq;
969
970 if (optlen < sizeof(struct group_req))
971 goto e_inval;
972 err = -EFAULT;
973 if (copy_from_user(&greq, optval, sizeof(greq)))
974 break;
975 psin = (struct sockaddr_in *)&greq.gr_group;
976 if (psin->sin_family != AF_INET)
977 goto e_inval;
978 memset(&mreq, 0, sizeof(mreq));
979 mreq.imr_multiaddr = psin->sin_addr;
980 mreq.imr_ifindex = greq.gr_interface;
981
982 if (optname == MCAST_JOIN_GROUP)
983 err = ip_mc_join_group(sk, &mreq);
984 else
985 err = ip_mc_leave_group(sk, &mreq);
986 break;
987 }
988 case MCAST_JOIN_SOURCE_GROUP:
989 case MCAST_LEAVE_SOURCE_GROUP:
990 case MCAST_BLOCK_SOURCE:
991 case MCAST_UNBLOCK_SOURCE:
992 {
993 struct group_source_req greqs;
994 struct ip_mreq_source mreqs;
995 struct sockaddr_in *psin;
996 int omode, add;
997
998 if (optlen != sizeof(struct group_source_req))
999 goto e_inval;
1000 if (copy_from_user(&greqs, optval, sizeof(greqs))) {
1001 err = -EFAULT;
1002 break;
1003 }
1004 if (greqs.gsr_group.ss_family != AF_INET ||
1005 greqs.gsr_source.ss_family != AF_INET) {
1006 err = -EADDRNOTAVAIL;
1007 break;
1008 }
1009 psin = (struct sockaddr_in *)&greqs.gsr_group;
1010 mreqs.imr_multiaddr = psin->sin_addr.s_addr;
1011 psin = (struct sockaddr_in *)&greqs.gsr_source;
1012 mreqs.imr_sourceaddr = psin->sin_addr.s_addr;
1013 mreqs.imr_interface = 0; /* use index for mc_source */
1014
1015 if (optname == MCAST_BLOCK_SOURCE) {
1016 omode = MCAST_EXCLUDE;
1017 add = 1;
1018 } else if (optname == MCAST_UNBLOCK_SOURCE) {
1019 omode = MCAST_EXCLUDE;
1020 add = 0;
1021 } else if (optname == MCAST_JOIN_SOURCE_GROUP) {
1022 struct ip_mreqn mreq;
1023
1024 psin = (struct sockaddr_in *)&greqs.gsr_group;
1025 mreq.imr_multiaddr = psin->sin_addr;
1026 mreq.imr_address.s_addr = 0;
1027 mreq.imr_ifindex = greqs.gsr_interface;
1028 err = ip_mc_join_group(sk, &mreq);
1029 if (err && err != -EADDRINUSE)
1030 break;
1031 greqs.gsr_interface = mreq.imr_ifindex;
1032 omode = MCAST_INCLUDE;
1033 add = 1;
1034 } else /* MCAST_LEAVE_SOURCE_GROUP */ {
1035 omode = MCAST_INCLUDE;
1036 add = 0;
1037 }
1038 err = ip_mc_source(add, omode, sk, &mreqs,
1039 greqs.gsr_interface);
1040 break;
1041 }
1042 case MCAST_MSFILTER:
1043 {
1044 struct sockaddr_in *psin;
1045 struct ip_msfilter *msf = NULL;
1046 struct group_filter *gsf = NULL;
1047 int msize, i, ifindex;
1048
1049 if (optlen < GROUP_FILTER_SIZE(0))
1050 goto e_inval;
1051 if (optlen > sysctl_optmem_max) {
1052 err = -ENOBUFS;
1053 break;
1054 }
1055 gsf = kmalloc(optlen, GFP_KERNEL);
1056 if (!gsf) {
1057 err = -ENOBUFS;
1058 break;
1059 }
1060 err = -EFAULT;
1061 if (copy_from_user(gsf, optval, optlen))
1062 goto mc_msf_out;
1063
1064 /* numsrc >= (4G-140)/128 overflow in 32 bits */
1065 if (gsf->gf_numsrc >= 0x1ffffff ||
1066 gsf->gf_numsrc > sysctl_igmp_max_msf) {
1067 err = -ENOBUFS;
1068 goto mc_msf_out;
1069 }
1070 if (GROUP_FILTER_SIZE(gsf->gf_numsrc) > optlen) {
1071 err = -EINVAL;
1072 goto mc_msf_out;
1073 }
1074 msize = IP_MSFILTER_SIZE(gsf->gf_numsrc);
1075 msf = kmalloc(msize, GFP_KERNEL);
1076 if (!msf) {
1077 err = -ENOBUFS;
1078 goto mc_msf_out;
1079 }
1080 ifindex = gsf->gf_interface;
1081 psin = (struct sockaddr_in *)&gsf->gf_group;
1082 if (psin->sin_family != AF_INET) {
1083 err = -EADDRNOTAVAIL;
1084 goto mc_msf_out;
1085 }
1086 msf->imsf_multiaddr = psin->sin_addr.s_addr;
1087 msf->imsf_interface = 0;
1088 msf->imsf_fmode = gsf->gf_fmode;
1089 msf->imsf_numsrc = gsf->gf_numsrc;
1090 err = -EADDRNOTAVAIL;
1091 for (i = 0; i < gsf->gf_numsrc; ++i) {
1092 psin = (struct sockaddr_in *)&gsf->gf_slist[i];
1093
1094 if (psin->sin_family != AF_INET)
1095 goto mc_msf_out;
1096 msf->imsf_slist[i] = psin->sin_addr.s_addr;
1097 }
1098 kfree(gsf);
1099 gsf = NULL;
1100
1101 err = ip_mc_msfilter(sk, msf, ifindex);
1102 mc_msf_out:
1103 kfree(msf);
1104 kfree(gsf);
1105 break;
1106 }
1107 case IP_MULTICAST_ALL:
1108 if (optlen < 1)
1109 goto e_inval;
1110 if (val != 0 && val != 1)
1111 goto e_inval;
1112 inet->mc_all = val;
1113 break;
1114 case IP_ROUTER_ALERT:
1115 err = ip_ra_control(sk, val ? 1 : 0, NULL);
1116 break;
1117
1118 case IP_FREEBIND:
1119 if (optlen < 1)
1120 goto e_inval;
1121 inet->freebind = !!val;
1122 break;
1123
1124 case IP_IPSEC_POLICY:
1125 case IP_XFRM_POLICY:
1126 err = -EPERM;
1127 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1128 break;
1129 err = xfrm_user_policy(sk, optname, optval, optlen);
1130 break;
1131
1132 case IP_TRANSPARENT:
1133 if (!!val && !ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
1134 !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1135 err = -EPERM;
1136 break;
1137 }
1138 if (optlen < 1)
1139 goto e_inval;
1140 inet->transparent = !!val;
1141 break;
1142
1143 case IP_MINTTL:
1144 if (optlen < 1)
1145 goto e_inval;
1146 if (val < 0 || val > 255)
1147 goto e_inval;
1148 inet->min_ttl = val;
1149 break;
1150
1151 default:
1152 err = -ENOPROTOOPT;
1153 break;
1154 }
1155 release_sock(sk);
1156 if (needs_rtnl)
1157 rtnl_unlock();
1158 return err;
1159
1160 e_inval:
1161 release_sock(sk);
1162 if (needs_rtnl)
1163 rtnl_unlock();
1164 return -EINVAL;
1165 }
1166
1167 /**
1168 * ipv4_pktinfo_prepare - transfer some info from rtable to skb
1169 * @sk: socket
1170 * @skb: buffer
1171 *
1172 * To support IP_CMSG_PKTINFO option, we store rt_iif and specific
1173 * destination in skb->cb[] before dst drop.
1174 * This way, receiver doesn't make cache line misses to read rtable.
1175 */
ipv4_pktinfo_prepare(const struct sock * sk,struct sk_buff * skb)1176 void ipv4_pktinfo_prepare(const struct sock *sk, struct sk_buff *skb)
1177 {
1178 struct in_pktinfo *pktinfo = PKTINFO_SKB_CB(skb);
1179 bool prepare = (inet_sk(sk)->cmsg_flags & IP_CMSG_PKTINFO) ||
1180 ipv6_sk_rxinfo(sk);
1181
1182 if (prepare && skb_rtable(skb)) {
1183 pktinfo->ipi_ifindex = inet_iif(skb);
1184 pktinfo->ipi_spec_dst.s_addr = fib_compute_spec_dst(skb);
1185 } else {
1186 pktinfo->ipi_ifindex = 0;
1187 pktinfo->ipi_spec_dst.s_addr = 0;
1188 }
1189 skb_dst_drop(skb);
1190 }
1191
ip_setsockopt(struct sock * sk,int level,int optname,char __user * optval,unsigned int optlen)1192 int ip_setsockopt(struct sock *sk, int level,
1193 int optname, char __user *optval, unsigned int optlen)
1194 {
1195 int err;
1196
1197 if (level != SOL_IP)
1198 return -ENOPROTOOPT;
1199
1200 err = do_ip_setsockopt(sk, level, optname, optval, optlen);
1201 #ifdef CONFIG_NETFILTER
1202 /* we need to exclude all possible ENOPROTOOPTs except default case */
1203 if (err == -ENOPROTOOPT && optname != IP_HDRINCL &&
1204 optname != IP_IPSEC_POLICY &&
1205 optname != IP_XFRM_POLICY &&
1206 !ip_mroute_opt(optname)) {
1207 lock_sock(sk);
1208 err = nf_setsockopt(sk, PF_INET, optname, optval, optlen);
1209 release_sock(sk);
1210 }
1211 #endif
1212 return err;
1213 }
1214 EXPORT_SYMBOL(ip_setsockopt);
1215
1216 #ifdef CONFIG_COMPAT
compat_ip_setsockopt(struct sock * sk,int level,int optname,char __user * optval,unsigned int optlen)1217 int compat_ip_setsockopt(struct sock *sk, int level, int optname,
1218 char __user *optval, unsigned int optlen)
1219 {
1220 int err;
1221
1222 if (level != SOL_IP)
1223 return -ENOPROTOOPT;
1224
1225 if (optname >= MCAST_JOIN_GROUP && optname <= MCAST_MSFILTER)
1226 return compat_mc_setsockopt(sk, level, optname, optval, optlen,
1227 ip_setsockopt);
1228
1229 err = do_ip_setsockopt(sk, level, optname, optval, optlen);
1230 #ifdef CONFIG_NETFILTER
1231 /* we need to exclude all possible ENOPROTOOPTs except default case */
1232 if (err == -ENOPROTOOPT && optname != IP_HDRINCL &&
1233 optname != IP_IPSEC_POLICY &&
1234 optname != IP_XFRM_POLICY &&
1235 !ip_mroute_opt(optname)) {
1236 lock_sock(sk);
1237 err = compat_nf_setsockopt(sk, PF_INET, optname,
1238 optval, optlen);
1239 release_sock(sk);
1240 }
1241 #endif
1242 return err;
1243 }
1244 EXPORT_SYMBOL(compat_ip_setsockopt);
1245 #endif
1246
1247 /*
1248 * Get the options. Note for future reference. The GET of IP options gets
1249 * the _received_ ones. The set sets the _sent_ ones.
1250 */
1251
do_ip_getsockopt(struct sock * sk,int level,int optname,char __user * optval,int __user * optlen,unsigned int flags)1252 static int do_ip_getsockopt(struct sock *sk, int level, int optname,
1253 char __user *optval, int __user *optlen, unsigned int flags)
1254 {
1255 struct inet_sock *inet = inet_sk(sk);
1256 int val;
1257 int len;
1258
1259 if (level != SOL_IP)
1260 return -EOPNOTSUPP;
1261
1262 if (ip_mroute_opt(optname))
1263 return ip_mroute_getsockopt(sk, optname, optval, optlen);
1264
1265 if (get_user(len, optlen))
1266 return -EFAULT;
1267 if (len < 0)
1268 return -EINVAL;
1269
1270 lock_sock(sk);
1271
1272 switch (optname) {
1273 case IP_OPTIONS:
1274 {
1275 unsigned char optbuf[sizeof(struct ip_options)+40];
1276 struct ip_options *opt = (struct ip_options *)optbuf;
1277 struct ip_options_rcu *inet_opt;
1278
1279 inet_opt = rcu_dereference_protected(inet->inet_opt,
1280 sock_owned_by_user(sk));
1281 opt->optlen = 0;
1282 if (inet_opt)
1283 memcpy(optbuf, &inet_opt->opt,
1284 sizeof(struct ip_options) +
1285 inet_opt->opt.optlen);
1286 release_sock(sk);
1287
1288 if (opt->optlen == 0)
1289 return put_user(0, optlen);
1290
1291 ip_options_undo(opt);
1292
1293 len = min_t(unsigned int, len, opt->optlen);
1294 if (put_user(len, optlen))
1295 return -EFAULT;
1296 if (copy_to_user(optval, opt->__data, len))
1297 return -EFAULT;
1298 return 0;
1299 }
1300 case IP_PKTINFO:
1301 val = (inet->cmsg_flags & IP_CMSG_PKTINFO) != 0;
1302 break;
1303 case IP_RECVTTL:
1304 val = (inet->cmsg_flags & IP_CMSG_TTL) != 0;
1305 break;
1306 case IP_RECVTOS:
1307 val = (inet->cmsg_flags & IP_CMSG_TOS) != 0;
1308 break;
1309 case IP_RECVOPTS:
1310 val = (inet->cmsg_flags & IP_CMSG_RECVOPTS) != 0;
1311 break;
1312 case IP_RETOPTS:
1313 val = (inet->cmsg_flags & IP_CMSG_RETOPTS) != 0;
1314 break;
1315 case IP_PASSSEC:
1316 val = (inet->cmsg_flags & IP_CMSG_PASSSEC) != 0;
1317 break;
1318 case IP_RECVORIGDSTADDR:
1319 val = (inet->cmsg_flags & IP_CMSG_ORIGDSTADDR) != 0;
1320 break;
1321 case IP_CHECKSUM:
1322 val = (inet->cmsg_flags & IP_CMSG_CHECKSUM) != 0;
1323 break;
1324 case IP_TOS:
1325 val = inet->tos;
1326 break;
1327 case IP_TTL:
1328 val = (inet->uc_ttl == -1 ?
1329 sysctl_ip_default_ttl :
1330 inet->uc_ttl);
1331 break;
1332 case IP_HDRINCL:
1333 val = inet->hdrincl;
1334 break;
1335 case IP_NODEFRAG:
1336 val = inet->nodefrag;
1337 break;
1338 case IP_MTU_DISCOVER:
1339 val = inet->pmtudisc;
1340 break;
1341 case IP_MTU:
1342 {
1343 struct dst_entry *dst;
1344 val = 0;
1345 dst = sk_dst_get(sk);
1346 if (dst) {
1347 val = dst_mtu(dst);
1348 dst_release(dst);
1349 }
1350 if (!val) {
1351 release_sock(sk);
1352 return -ENOTCONN;
1353 }
1354 break;
1355 }
1356 case IP_RECVERR:
1357 val = inet->recverr;
1358 break;
1359 case IP_MULTICAST_TTL:
1360 val = inet->mc_ttl;
1361 break;
1362 case IP_MULTICAST_LOOP:
1363 val = inet->mc_loop;
1364 break;
1365 case IP_UNICAST_IF:
1366 val = (__force int)htonl((__u32) inet->uc_index);
1367 break;
1368 case IP_MULTICAST_IF:
1369 {
1370 struct in_addr addr;
1371 len = min_t(unsigned int, len, sizeof(struct in_addr));
1372 addr.s_addr = inet->mc_addr;
1373 release_sock(sk);
1374
1375 if (put_user(len, optlen))
1376 return -EFAULT;
1377 if (copy_to_user(optval, &addr, len))
1378 return -EFAULT;
1379 return 0;
1380 }
1381 case IP_MSFILTER:
1382 {
1383 struct ip_msfilter msf;
1384 int err;
1385
1386 if (len < IP_MSFILTER_SIZE(0)) {
1387 release_sock(sk);
1388 return -EINVAL;
1389 }
1390 if (copy_from_user(&msf, optval, IP_MSFILTER_SIZE(0))) {
1391 release_sock(sk);
1392 return -EFAULT;
1393 }
1394 err = ip_mc_msfget(sk, &msf,
1395 (struct ip_msfilter __user *)optval, optlen);
1396 release_sock(sk);
1397 return err;
1398 }
1399 case MCAST_MSFILTER:
1400 {
1401 struct group_filter gsf;
1402 int err;
1403
1404 if (len < GROUP_FILTER_SIZE(0)) {
1405 release_sock(sk);
1406 return -EINVAL;
1407 }
1408 if (copy_from_user(&gsf, optval, GROUP_FILTER_SIZE(0))) {
1409 release_sock(sk);
1410 return -EFAULT;
1411 }
1412 err = ip_mc_gsfget(sk, &gsf,
1413 (struct group_filter __user *)optval,
1414 optlen);
1415 release_sock(sk);
1416 return err;
1417 }
1418 case IP_MULTICAST_ALL:
1419 val = inet->mc_all;
1420 break;
1421 case IP_PKTOPTIONS:
1422 {
1423 struct msghdr msg;
1424
1425 release_sock(sk);
1426
1427 if (sk->sk_type != SOCK_STREAM)
1428 return -ENOPROTOOPT;
1429
1430 msg.msg_control = (__force void *) optval;
1431 msg.msg_controllen = len;
1432 msg.msg_flags = flags;
1433
1434 if (inet->cmsg_flags & IP_CMSG_PKTINFO) {
1435 struct in_pktinfo info;
1436
1437 info.ipi_addr.s_addr = inet->inet_rcv_saddr;
1438 info.ipi_spec_dst.s_addr = inet->inet_rcv_saddr;
1439 info.ipi_ifindex = inet->mc_index;
1440 put_cmsg(&msg, SOL_IP, IP_PKTINFO, sizeof(info), &info);
1441 }
1442 if (inet->cmsg_flags & IP_CMSG_TTL) {
1443 int hlim = inet->mc_ttl;
1444 put_cmsg(&msg, SOL_IP, IP_TTL, sizeof(hlim), &hlim);
1445 }
1446 if (inet->cmsg_flags & IP_CMSG_TOS) {
1447 int tos = inet->rcv_tos;
1448 put_cmsg(&msg, SOL_IP, IP_TOS, sizeof(tos), &tos);
1449 }
1450 len -= msg.msg_controllen;
1451 return put_user(len, optlen);
1452 }
1453 case IP_FREEBIND:
1454 val = inet->freebind;
1455 break;
1456 case IP_TRANSPARENT:
1457 val = inet->transparent;
1458 break;
1459 case IP_MINTTL:
1460 val = inet->min_ttl;
1461 break;
1462 default:
1463 release_sock(sk);
1464 return -ENOPROTOOPT;
1465 }
1466 release_sock(sk);
1467
1468 if (len < sizeof(int) && len > 0 && val >= 0 && val <= 255) {
1469 unsigned char ucval = (unsigned char)val;
1470 len = 1;
1471 if (put_user(len, optlen))
1472 return -EFAULT;
1473 if (copy_to_user(optval, &ucval, 1))
1474 return -EFAULT;
1475 } else {
1476 len = min_t(unsigned int, sizeof(int), len);
1477 if (put_user(len, optlen))
1478 return -EFAULT;
1479 if (copy_to_user(optval, &val, len))
1480 return -EFAULT;
1481 }
1482 return 0;
1483 }
1484
ip_getsockopt(struct sock * sk,int level,int optname,char __user * optval,int __user * optlen)1485 int ip_getsockopt(struct sock *sk, int level,
1486 int optname, char __user *optval, int __user *optlen)
1487 {
1488 int err;
1489
1490 err = do_ip_getsockopt(sk, level, optname, optval, optlen, 0);
1491 #ifdef CONFIG_NETFILTER
1492 /* we need to exclude all possible ENOPROTOOPTs except default case */
1493 if (err == -ENOPROTOOPT && optname != IP_PKTOPTIONS &&
1494 !ip_mroute_opt(optname)) {
1495 int len;
1496
1497 if (get_user(len, optlen))
1498 return -EFAULT;
1499
1500 lock_sock(sk);
1501 err = nf_getsockopt(sk, PF_INET, optname, optval,
1502 &len);
1503 release_sock(sk);
1504 if (err >= 0)
1505 err = put_user(len, optlen);
1506 return err;
1507 }
1508 #endif
1509 return err;
1510 }
1511 EXPORT_SYMBOL(ip_getsockopt);
1512
1513 #ifdef CONFIG_COMPAT
compat_ip_getsockopt(struct sock * sk,int level,int optname,char __user * optval,int __user * optlen)1514 int compat_ip_getsockopt(struct sock *sk, int level, int optname,
1515 char __user *optval, int __user *optlen)
1516 {
1517 int err;
1518
1519 if (optname == MCAST_MSFILTER)
1520 return compat_mc_getsockopt(sk, level, optname, optval, optlen,
1521 ip_getsockopt);
1522
1523 err = do_ip_getsockopt(sk, level, optname, optval, optlen,
1524 MSG_CMSG_COMPAT);
1525
1526 #ifdef CONFIG_NETFILTER
1527 /* we need to exclude all possible ENOPROTOOPTs except default case */
1528 if (err == -ENOPROTOOPT && optname != IP_PKTOPTIONS &&
1529 !ip_mroute_opt(optname)) {
1530 int len;
1531
1532 if (get_user(len, optlen))
1533 return -EFAULT;
1534
1535 lock_sock(sk);
1536 err = compat_nf_getsockopt(sk, PF_INET, optname, optval, &len);
1537 release_sock(sk);
1538 if (err >= 0)
1539 err = put_user(len, optlen);
1540 return err;
1541 }
1542 #endif
1543 return err;
1544 }
1545 EXPORT_SYMBOL(compat_ip_getsockopt);
1546 #endif
1547