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 #include <linux/bpfilter.h>
51
52 /*
53 * SOL_IP control messages.
54 */
55
ip_cmsg_recv_pktinfo(struct msghdr * msg,struct sk_buff * skb)56 static void ip_cmsg_recv_pktinfo(struct msghdr *msg, struct sk_buff *skb)
57 {
58 struct in_pktinfo info = *PKTINFO_SKB_CB(skb);
59
60 info.ipi_addr.s_addr = ip_hdr(skb)->daddr;
61
62 put_cmsg(msg, SOL_IP, IP_PKTINFO, sizeof(info), &info);
63 }
64
ip_cmsg_recv_ttl(struct msghdr * msg,struct sk_buff * skb)65 static void ip_cmsg_recv_ttl(struct msghdr *msg, struct sk_buff *skb)
66 {
67 int ttl = ip_hdr(skb)->ttl;
68 put_cmsg(msg, SOL_IP, IP_TTL, sizeof(int), &ttl);
69 }
70
ip_cmsg_recv_tos(struct msghdr * msg,struct sk_buff * skb)71 static void ip_cmsg_recv_tos(struct msghdr *msg, struct sk_buff *skb)
72 {
73 put_cmsg(msg, SOL_IP, IP_TOS, 1, &ip_hdr(skb)->tos);
74 }
75
ip_cmsg_recv_opts(struct msghdr * msg,struct sk_buff * skb)76 static void ip_cmsg_recv_opts(struct msghdr *msg, struct sk_buff *skb)
77 {
78 if (IPCB(skb)->opt.optlen == 0)
79 return;
80
81 put_cmsg(msg, SOL_IP, IP_RECVOPTS, IPCB(skb)->opt.optlen,
82 ip_hdr(skb) + 1);
83 }
84
85
ip_cmsg_recv_retopts(struct net * net,struct msghdr * msg,struct sk_buff * skb)86 static void ip_cmsg_recv_retopts(struct net *net, struct msghdr *msg,
87 struct sk_buff *skb)
88 {
89 unsigned char optbuf[sizeof(struct ip_options) + 40];
90 struct ip_options *opt = (struct ip_options *)optbuf;
91
92 if (IPCB(skb)->opt.optlen == 0)
93 return;
94
95 if (ip_options_echo(net, opt, skb)) {
96 msg->msg_flags |= MSG_CTRUNC;
97 return;
98 }
99 ip_options_undo(opt);
100
101 put_cmsg(msg, SOL_IP, IP_RETOPTS, opt->optlen, opt->__data);
102 }
103
ip_cmsg_recv_fragsize(struct msghdr * msg,struct sk_buff * skb)104 static void ip_cmsg_recv_fragsize(struct msghdr *msg, struct sk_buff *skb)
105 {
106 int val;
107
108 if (IPCB(skb)->frag_max_size == 0)
109 return;
110
111 val = IPCB(skb)->frag_max_size;
112 put_cmsg(msg, SOL_IP, IP_RECVFRAGSIZE, sizeof(val), &val);
113 }
114
ip_cmsg_recv_checksum(struct msghdr * msg,struct sk_buff * skb,int tlen,int offset)115 static void ip_cmsg_recv_checksum(struct msghdr *msg, struct sk_buff *skb,
116 int tlen, int offset)
117 {
118 __wsum csum = skb->csum;
119
120 if (skb->ip_summed != CHECKSUM_COMPLETE)
121 return;
122
123 if (offset != 0) {
124 int tend_off = skb_transport_offset(skb) + tlen;
125 csum = csum_sub(csum, skb_checksum(skb, tend_off, offset, 0));
126 }
127
128 put_cmsg(msg, SOL_IP, IP_CHECKSUM, sizeof(__wsum), &csum);
129 }
130
ip_cmsg_recv_security(struct msghdr * msg,struct sk_buff * skb)131 static void ip_cmsg_recv_security(struct msghdr *msg, struct sk_buff *skb)
132 {
133 char *secdata;
134 u32 seclen, secid;
135 int err;
136
137 err = security_socket_getpeersec_dgram(NULL, skb, &secid);
138 if (err)
139 return;
140
141 err = security_secid_to_secctx(secid, &secdata, &seclen);
142 if (err)
143 return;
144
145 put_cmsg(msg, SOL_IP, SCM_SECURITY, seclen, secdata);
146 security_release_secctx(secdata, seclen);
147 }
148
ip_cmsg_recv_dstaddr(struct msghdr * msg,struct sk_buff * skb)149 static void ip_cmsg_recv_dstaddr(struct msghdr *msg, struct sk_buff *skb)
150 {
151 __be16 _ports[2], *ports;
152 struct sockaddr_in sin;
153
154 /* All current transport protocols have the port numbers in the
155 * first four bytes of the transport header and this function is
156 * written with this assumption in mind.
157 */
158 ports = skb_header_pointer(skb, skb_transport_offset(skb),
159 sizeof(_ports), &_ports);
160 if (!ports)
161 return;
162
163 sin.sin_family = AF_INET;
164 sin.sin_addr.s_addr = ip_hdr(skb)->daddr;
165 sin.sin_port = ports[1];
166 memset(sin.sin_zero, 0, sizeof(sin.sin_zero));
167
168 put_cmsg(msg, SOL_IP, IP_ORIGDSTADDR, sizeof(sin), &sin);
169 }
170
ip_cmsg_recv_offset(struct msghdr * msg,struct sock * sk,struct sk_buff * skb,int tlen,int offset)171 void ip_cmsg_recv_offset(struct msghdr *msg, struct sock *sk,
172 struct sk_buff *skb, int tlen, int offset)
173 {
174 struct inet_sock *inet = inet_sk(sk);
175 unsigned int flags = inet->cmsg_flags;
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 }
240 EXPORT_SYMBOL(ip_cmsg_recv_offset);
241
ip_cmsg_send(struct sock * sk,struct msghdr * msg,struct ipcm_cookie * ipc,bool allow_ipv6)242 int 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, msg, 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, CMSG_DATA(cmsg),
284 err < 40 ? err : 40);
285 if (err)
286 return err;
287 break;
288 case IP_PKTINFO:
289 {
290 struct in_pktinfo *info;
291 if (cmsg->cmsg_len != CMSG_LEN(sizeof(struct in_pktinfo)))
292 return -EINVAL;
293 info = (struct in_pktinfo *)CMSG_DATA(cmsg);
294 if (info->ipi_ifindex)
295 ipc->oif = info->ipi_ifindex;
296 ipc->addr = info->ipi_spec_dst.s_addr;
297 break;
298 }
299 case IP_TTL:
300 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
301 return -EINVAL;
302 val = *(int *)CMSG_DATA(cmsg);
303 if (val < 1 || val > 255)
304 return -EINVAL;
305 ipc->ttl = val;
306 break;
307 case IP_TOS:
308 if (cmsg->cmsg_len == CMSG_LEN(sizeof(int)))
309 val = *(int *)CMSG_DATA(cmsg);
310 else if (cmsg->cmsg_len == CMSG_LEN(sizeof(u8)))
311 val = *(u8 *)CMSG_DATA(cmsg);
312 else
313 return -EINVAL;
314 if (val < 0 || val > 255)
315 return -EINVAL;
316 ipc->tos = val;
317 ipc->priority = rt_tos2priority(ipc->tos);
318 break;
319
320 default:
321 return -EINVAL;
322 }
323 }
324 return 0;
325 }
326
ip_ra_destroy_rcu(struct rcu_head * head)327 static void ip_ra_destroy_rcu(struct rcu_head *head)
328 {
329 struct ip_ra_chain *ra = container_of(head, struct ip_ra_chain, rcu);
330
331 sock_put(ra->saved_sk);
332 kfree(ra);
333 }
334
ip_ra_control(struct sock * sk,unsigned char on,void (* destructor)(struct sock *))335 int ip_ra_control(struct sock *sk, unsigned char on,
336 void (*destructor)(struct sock *))
337 {
338 struct ip_ra_chain *ra, *new_ra;
339 struct ip_ra_chain __rcu **rap;
340 struct net *net = sock_net(sk);
341
342 if (sk->sk_type != SOCK_RAW || inet_sk(sk)->inet_num == IPPROTO_RAW)
343 return -EINVAL;
344
345 new_ra = on ? kmalloc(sizeof(*new_ra), GFP_KERNEL) : NULL;
346 if (on && !new_ra)
347 return -ENOMEM;
348
349 mutex_lock(&net->ipv4.ra_mutex);
350 for (rap = &net->ipv4.ra_chain;
351 (ra = rcu_dereference_protected(*rap,
352 lockdep_is_held(&net->ipv4.ra_mutex))) != NULL;
353 rap = &ra->next) {
354 if (ra->sk == sk) {
355 if (on) {
356 mutex_unlock(&net->ipv4.ra_mutex);
357 kfree(new_ra);
358 return -EADDRINUSE;
359 }
360 /* dont let ip_call_ra_chain() use sk again */
361 ra->sk = NULL;
362 RCU_INIT_POINTER(*rap, ra->next);
363 mutex_unlock(&net->ipv4.ra_mutex);
364
365 if (ra->destructor)
366 ra->destructor(sk);
367 /*
368 * Delay sock_put(sk) and kfree(ra) after one rcu grace
369 * period. This guarantee ip_call_ra_chain() dont need
370 * to mess with socket refcounts.
371 */
372 ra->saved_sk = sk;
373 call_rcu(&ra->rcu, ip_ra_destroy_rcu);
374 return 0;
375 }
376 }
377 if (!new_ra) {
378 mutex_unlock(&net->ipv4.ra_mutex);
379 return -ENOBUFS;
380 }
381 new_ra->sk = sk;
382 new_ra->destructor = destructor;
383
384 RCU_INIT_POINTER(new_ra->next, ra);
385 rcu_assign_pointer(*rap, new_ra);
386 sock_hold(sk);
387 mutex_unlock(&net->ipv4.ra_mutex);
388
389 return 0;
390 }
391
ip_icmp_error(struct sock * sk,struct sk_buff * skb,int err,__be16 port,u32 info,u8 * payload)392 void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
393 __be16 port, u32 info, u8 *payload)
394 {
395 struct sock_exterr_skb *serr;
396
397 skb = skb_clone(skb, GFP_ATOMIC);
398 if (!skb)
399 return;
400
401 serr = SKB_EXT_ERR(skb);
402 serr->ee.ee_errno = err;
403 serr->ee.ee_origin = SO_EE_ORIGIN_ICMP;
404 serr->ee.ee_type = icmp_hdr(skb)->type;
405 serr->ee.ee_code = icmp_hdr(skb)->code;
406 serr->ee.ee_pad = 0;
407 serr->ee.ee_info = info;
408 serr->ee.ee_data = 0;
409 serr->addr_offset = (u8 *)&(((struct iphdr *)(icmp_hdr(skb) + 1))->daddr) -
410 skb_network_header(skb);
411 serr->port = port;
412
413 if (skb_pull(skb, payload - skb->data)) {
414 skb_reset_transport_header(skb);
415 if (sock_queue_err_skb(sk, skb) == 0)
416 return;
417 }
418 kfree_skb(skb);
419 }
420
ip_local_error(struct sock * sk,int err,__be32 daddr,__be16 port,u32 info)421 void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 port, u32 info)
422 {
423 struct inet_sock *inet = inet_sk(sk);
424 struct sock_exterr_skb *serr;
425 struct iphdr *iph;
426 struct sk_buff *skb;
427
428 if (!inet->recverr)
429 return;
430
431 skb = alloc_skb(sizeof(struct iphdr), GFP_ATOMIC);
432 if (!skb)
433 return;
434
435 skb_put(skb, sizeof(struct iphdr));
436 skb_reset_network_header(skb);
437 iph = ip_hdr(skb);
438 iph->daddr = daddr;
439
440 serr = SKB_EXT_ERR(skb);
441 serr->ee.ee_errno = err;
442 serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
443 serr->ee.ee_type = 0;
444 serr->ee.ee_code = 0;
445 serr->ee.ee_pad = 0;
446 serr->ee.ee_info = info;
447 serr->ee.ee_data = 0;
448 serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
449 serr->port = port;
450
451 __skb_pull(skb, skb_tail_pointer(skb) - skb->data);
452 skb_reset_transport_header(skb);
453
454 if (sock_queue_err_skb(sk, skb))
455 kfree_skb(skb);
456 }
457
458 /* For some errors we have valid addr_offset even with zero payload and
459 * zero port. Also, addr_offset should be supported if port is set.
460 */
ipv4_datagram_support_addr(struct sock_exterr_skb * serr)461 static inline bool ipv4_datagram_support_addr(struct sock_exterr_skb *serr)
462 {
463 return serr->ee.ee_origin == SO_EE_ORIGIN_ICMP ||
464 serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL || serr->port;
465 }
466
467 /* IPv4 supports cmsg on all imcp errors and some timestamps
468 *
469 * Timestamp code paths do not initialize the fields expected by cmsg:
470 * the PKTINFO fields in skb->cb[]. Fill those in here.
471 */
ipv4_datagram_support_cmsg(const struct sock * sk,struct sk_buff * skb,int ee_origin)472 static bool ipv4_datagram_support_cmsg(const struct sock *sk,
473 struct sk_buff *skb,
474 int ee_origin)
475 {
476 struct in_pktinfo *info;
477
478 if (ee_origin == SO_EE_ORIGIN_ICMP)
479 return true;
480
481 if (ee_origin == SO_EE_ORIGIN_LOCAL)
482 return false;
483
484 /* Support IP_PKTINFO on tstamp packets if requested, to correlate
485 * timestamp with egress dev. Not possible for packets without iif
486 * or without payload (SOF_TIMESTAMPING_OPT_TSONLY).
487 */
488 info = PKTINFO_SKB_CB(skb);
489 if (!(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_CMSG) ||
490 !info->ipi_ifindex)
491 return false;
492
493 info->ipi_spec_dst.s_addr = ip_hdr(skb)->saddr;
494 return true;
495 }
496
497 /*
498 * Handle MSG_ERRQUEUE
499 */
ip_recv_error(struct sock * sk,struct msghdr * msg,int len,int * addr_len)500 int ip_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
501 {
502 struct sock_exterr_skb *serr;
503 struct sk_buff *skb;
504 DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name);
505 struct {
506 struct sock_extended_err ee;
507 struct sockaddr_in offender;
508 } errhdr;
509 int err;
510 int copied;
511
512 err = -EAGAIN;
513 skb = sock_dequeue_err_skb(sk);
514 if (!skb)
515 goto out;
516
517 copied = skb->len;
518 if (copied > len) {
519 msg->msg_flags |= MSG_TRUNC;
520 copied = len;
521 }
522 err = skb_copy_datagram_msg(skb, 0, msg, copied);
523 if (unlikely(err)) {
524 kfree_skb(skb);
525 return err;
526 }
527 sock_recv_timestamp(msg, sk, skb);
528
529 serr = SKB_EXT_ERR(skb);
530
531 if (sin && ipv4_datagram_support_addr(serr)) {
532 sin->sin_family = AF_INET;
533 sin->sin_addr.s_addr = *(__be32 *)(skb_network_header(skb) +
534 serr->addr_offset);
535 sin->sin_port = serr->port;
536 memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
537 *addr_len = sizeof(*sin);
538 }
539
540 memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
541 sin = &errhdr.offender;
542 memset(sin, 0, sizeof(*sin));
543
544 if (ipv4_datagram_support_cmsg(sk, skb, serr->ee.ee_origin)) {
545 sin->sin_family = AF_INET;
546 sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
547 if (inet_sk(sk)->cmsg_flags)
548 ip_cmsg_recv(msg, skb);
549 }
550
551 put_cmsg(msg, SOL_IP, IP_RECVERR, sizeof(errhdr), &errhdr);
552
553 /* Now we could try to dump offended packet options */
554
555 msg->msg_flags |= MSG_ERRQUEUE;
556 err = copied;
557
558 consume_skb(skb);
559 out:
560 return err;
561 }
562
563
564 /*
565 * Socket option code for IP. This is the end of the line after any
566 * TCP,UDP etc options on an IP socket.
567 */
setsockopt_needs_rtnl(int optname)568 static bool setsockopt_needs_rtnl(int optname)
569 {
570 switch (optname) {
571 case IP_ADD_MEMBERSHIP:
572 case IP_ADD_SOURCE_MEMBERSHIP:
573 case IP_BLOCK_SOURCE:
574 case IP_DROP_MEMBERSHIP:
575 case IP_DROP_SOURCE_MEMBERSHIP:
576 case IP_MSFILTER:
577 case IP_UNBLOCK_SOURCE:
578 case MCAST_BLOCK_SOURCE:
579 case MCAST_MSFILTER:
580 case MCAST_JOIN_GROUP:
581 case MCAST_JOIN_SOURCE_GROUP:
582 case MCAST_LEAVE_GROUP:
583 case MCAST_LEAVE_SOURCE_GROUP:
584 case MCAST_UNBLOCK_SOURCE:
585 return true;
586 }
587 return false;
588 }
589
do_ip_setsockopt(struct sock * sk,int level,int optname,char __user * optval,unsigned int optlen)590 static int do_ip_setsockopt(struct sock *sk, int level,
591 int optname, char __user *optval, unsigned int optlen)
592 {
593 struct inet_sock *inet = inet_sk(sk);
594 struct net *net = sock_net(sk);
595 int val = 0, err;
596 bool needs_rtnl = setsockopt_needs_rtnl(optname);
597
598 switch (optname) {
599 case IP_PKTINFO:
600 case IP_RECVTTL:
601 case IP_RECVOPTS:
602 case IP_RECVTOS:
603 case IP_RETOPTS:
604 case IP_TOS:
605 case IP_TTL:
606 case IP_HDRINCL:
607 case IP_MTU_DISCOVER:
608 case IP_RECVERR:
609 case IP_ROUTER_ALERT:
610 case IP_FREEBIND:
611 case IP_PASSSEC:
612 case IP_TRANSPARENT:
613 case IP_MINTTL:
614 case IP_NODEFRAG:
615 case IP_BIND_ADDRESS_NO_PORT:
616 case IP_UNICAST_IF:
617 case IP_MULTICAST_TTL:
618 case IP_MULTICAST_ALL:
619 case IP_MULTICAST_LOOP:
620 case IP_RECVORIGDSTADDR:
621 case IP_CHECKSUM:
622 case IP_RECVFRAGSIZE:
623 if (optlen >= sizeof(int)) {
624 if (get_user(val, (int __user *) optval))
625 return -EFAULT;
626 } else if (optlen >= sizeof(char)) {
627 unsigned char ucval;
628
629 if (get_user(ucval, (unsigned char __user *) optval))
630 return -EFAULT;
631 val = (int) ucval;
632 }
633 }
634
635 /* If optlen==0, it is equivalent to val == 0 */
636
637 if (optname == IP_ROUTER_ALERT)
638 return ip_ra_control(sk, val ? 1 : 0, NULL);
639 if (ip_mroute_opt(optname))
640 return ip_mroute_setsockopt(sk, optname, optval, optlen);
641
642 err = 0;
643 if (needs_rtnl)
644 rtnl_lock();
645 lock_sock(sk);
646
647 switch (optname) {
648 case IP_OPTIONS:
649 {
650 struct ip_options_rcu *old, *opt = NULL;
651
652 if (optlen > 40)
653 goto e_inval;
654 err = ip_options_get_from_user(sock_net(sk), &opt,
655 optval, optlen);
656 if (err)
657 break;
658 old = rcu_dereference_protected(inet->inet_opt,
659 lockdep_sock_is_held(sk));
660 if (inet->is_icsk) {
661 struct inet_connection_sock *icsk = inet_csk(sk);
662 #if IS_ENABLED(CONFIG_IPV6)
663 if (sk->sk_family == PF_INET ||
664 (!((1 << sk->sk_state) &
665 (TCPF_LISTEN | TCPF_CLOSE)) &&
666 inet->inet_daddr != LOOPBACK4_IPV6)) {
667 #endif
668 if (old)
669 icsk->icsk_ext_hdr_len -= old->opt.optlen;
670 if (opt)
671 icsk->icsk_ext_hdr_len += opt->opt.optlen;
672 icsk->icsk_sync_mss(sk, icsk->icsk_pmtu_cookie);
673 #if IS_ENABLED(CONFIG_IPV6)
674 }
675 #endif
676 }
677 rcu_assign_pointer(inet->inet_opt, opt);
678 if (old)
679 kfree_rcu(old, rcu);
680 break;
681 }
682 case IP_PKTINFO:
683 if (val)
684 inet->cmsg_flags |= IP_CMSG_PKTINFO;
685 else
686 inet->cmsg_flags &= ~IP_CMSG_PKTINFO;
687 break;
688 case IP_RECVTTL:
689 if (val)
690 inet->cmsg_flags |= IP_CMSG_TTL;
691 else
692 inet->cmsg_flags &= ~IP_CMSG_TTL;
693 break;
694 case IP_RECVTOS:
695 if (val)
696 inet->cmsg_flags |= IP_CMSG_TOS;
697 else
698 inet->cmsg_flags &= ~IP_CMSG_TOS;
699 break;
700 case IP_RECVOPTS:
701 if (val)
702 inet->cmsg_flags |= IP_CMSG_RECVOPTS;
703 else
704 inet->cmsg_flags &= ~IP_CMSG_RECVOPTS;
705 break;
706 case IP_RETOPTS:
707 if (val)
708 inet->cmsg_flags |= IP_CMSG_RETOPTS;
709 else
710 inet->cmsg_flags &= ~IP_CMSG_RETOPTS;
711 break;
712 case IP_PASSSEC:
713 if (val)
714 inet->cmsg_flags |= IP_CMSG_PASSSEC;
715 else
716 inet->cmsg_flags &= ~IP_CMSG_PASSSEC;
717 break;
718 case IP_RECVORIGDSTADDR:
719 if (val)
720 inet->cmsg_flags |= IP_CMSG_ORIGDSTADDR;
721 else
722 inet->cmsg_flags &= ~IP_CMSG_ORIGDSTADDR;
723 break;
724 case IP_CHECKSUM:
725 if (val) {
726 if (!(inet->cmsg_flags & IP_CMSG_CHECKSUM)) {
727 inet_inc_convert_csum(sk);
728 inet->cmsg_flags |= IP_CMSG_CHECKSUM;
729 }
730 } else {
731 if (inet->cmsg_flags & IP_CMSG_CHECKSUM) {
732 inet_dec_convert_csum(sk);
733 inet->cmsg_flags &= ~IP_CMSG_CHECKSUM;
734 }
735 }
736 break;
737 case IP_RECVFRAGSIZE:
738 if (sk->sk_type != SOCK_RAW && sk->sk_type != SOCK_DGRAM)
739 goto e_inval;
740 if (val)
741 inet->cmsg_flags |= IP_CMSG_RECVFRAGSIZE;
742 else
743 inet->cmsg_flags &= ~IP_CMSG_RECVFRAGSIZE;
744 break;
745 case IP_TOS: /* This sets both TOS and Precedence */
746 if (sk->sk_type == SOCK_STREAM) {
747 val &= ~INET_ECN_MASK;
748 val |= inet->tos & INET_ECN_MASK;
749 }
750 if (inet->tos != val) {
751 inet->tos = val;
752 sk->sk_priority = rt_tos2priority(val);
753 sk_dst_reset(sk);
754 }
755 break;
756 case IP_TTL:
757 if (optlen < 1)
758 goto e_inval;
759 if (val != -1 && (val < 1 || val > 255))
760 goto e_inval;
761 inet->uc_ttl = val;
762 break;
763 case IP_HDRINCL:
764 if (sk->sk_type != SOCK_RAW) {
765 err = -ENOPROTOOPT;
766 break;
767 }
768 inet->hdrincl = val ? 1 : 0;
769 break;
770 case IP_NODEFRAG:
771 if (sk->sk_type != SOCK_RAW) {
772 err = -ENOPROTOOPT;
773 break;
774 }
775 inet->nodefrag = val ? 1 : 0;
776 break;
777 case IP_BIND_ADDRESS_NO_PORT:
778 inet->bind_address_no_port = val ? 1 : 0;
779 break;
780 case IP_MTU_DISCOVER:
781 if (val < IP_PMTUDISC_DONT || val > IP_PMTUDISC_OMIT)
782 goto e_inval;
783 inet->pmtudisc = val;
784 break;
785 case IP_RECVERR:
786 inet->recverr = !!val;
787 if (!val)
788 skb_queue_purge(&sk->sk_error_queue);
789 break;
790 case IP_MULTICAST_TTL:
791 if (sk->sk_type == SOCK_STREAM)
792 goto e_inval;
793 if (optlen < 1)
794 goto e_inval;
795 if (val == -1)
796 val = 1;
797 if (val < 0 || val > 255)
798 goto e_inval;
799 inet->mc_ttl = val;
800 break;
801 case IP_MULTICAST_LOOP:
802 if (optlen < 1)
803 goto e_inval;
804 inet->mc_loop = !!val;
805 break;
806 case IP_UNICAST_IF:
807 {
808 struct net_device *dev = NULL;
809 int ifindex;
810 int midx;
811
812 if (optlen != sizeof(int))
813 goto e_inval;
814
815 ifindex = (__force int)ntohl((__force __be32)val);
816 if (ifindex == 0) {
817 inet->uc_index = 0;
818 err = 0;
819 break;
820 }
821
822 dev = dev_get_by_index(sock_net(sk), ifindex);
823 err = -EADDRNOTAVAIL;
824 if (!dev)
825 break;
826
827 midx = l3mdev_master_ifindex(dev);
828 dev_put(dev);
829
830 err = -EINVAL;
831 if (sk->sk_bound_dev_if &&
832 (!midx || midx != sk->sk_bound_dev_if))
833 break;
834
835 inet->uc_index = ifindex;
836 err = 0;
837 break;
838 }
839 case IP_MULTICAST_IF:
840 {
841 struct ip_mreqn mreq;
842 struct net_device *dev = NULL;
843 int midx;
844
845 if (sk->sk_type == SOCK_STREAM)
846 goto e_inval;
847 /*
848 * Check the arguments are allowable
849 */
850
851 if (optlen < sizeof(struct in_addr))
852 goto e_inval;
853
854 err = -EFAULT;
855 if (optlen >= sizeof(struct ip_mreqn)) {
856 if (copy_from_user(&mreq, optval, sizeof(mreq)))
857 break;
858 } else {
859 memset(&mreq, 0, sizeof(mreq));
860 if (optlen >= sizeof(struct ip_mreq)) {
861 if (copy_from_user(&mreq, optval,
862 sizeof(struct ip_mreq)))
863 break;
864 } else if (optlen >= sizeof(struct in_addr)) {
865 if (copy_from_user(&mreq.imr_address, optval,
866 sizeof(struct in_addr)))
867 break;
868 }
869 }
870
871 if (!mreq.imr_ifindex) {
872 if (mreq.imr_address.s_addr == htonl(INADDR_ANY)) {
873 inet->mc_index = 0;
874 inet->mc_addr = 0;
875 err = 0;
876 break;
877 }
878 dev = ip_dev_find(sock_net(sk), mreq.imr_address.s_addr);
879 if (dev)
880 mreq.imr_ifindex = dev->ifindex;
881 } else
882 dev = dev_get_by_index(sock_net(sk), mreq.imr_ifindex);
883
884
885 err = -EADDRNOTAVAIL;
886 if (!dev)
887 break;
888
889 midx = l3mdev_master_ifindex(dev);
890
891 dev_put(dev);
892
893 err = -EINVAL;
894 if (sk->sk_bound_dev_if &&
895 mreq.imr_ifindex != sk->sk_bound_dev_if &&
896 (!midx || midx != sk->sk_bound_dev_if))
897 break;
898
899 inet->mc_index = mreq.imr_ifindex;
900 inet->mc_addr = mreq.imr_address.s_addr;
901 err = 0;
902 break;
903 }
904
905 case IP_ADD_MEMBERSHIP:
906 case IP_DROP_MEMBERSHIP:
907 {
908 struct ip_mreqn mreq;
909
910 err = -EPROTO;
911 if (inet_sk(sk)->is_icsk)
912 break;
913
914 if (optlen < sizeof(struct ip_mreq))
915 goto e_inval;
916 err = -EFAULT;
917 if (optlen >= sizeof(struct ip_mreqn)) {
918 if (copy_from_user(&mreq, optval, sizeof(mreq)))
919 break;
920 } else {
921 memset(&mreq, 0, sizeof(mreq));
922 if (copy_from_user(&mreq, optval, sizeof(struct ip_mreq)))
923 break;
924 }
925
926 if (optname == IP_ADD_MEMBERSHIP)
927 err = ip_mc_join_group(sk, &mreq);
928 else
929 err = ip_mc_leave_group(sk, &mreq);
930 break;
931 }
932 case IP_MSFILTER:
933 {
934 struct ip_msfilter *msf;
935
936 if (optlen < IP_MSFILTER_SIZE(0))
937 goto e_inval;
938 if (optlen > sysctl_optmem_max) {
939 err = -ENOBUFS;
940 break;
941 }
942 msf = memdup_user(optval, optlen);
943 if (IS_ERR(msf)) {
944 err = PTR_ERR(msf);
945 break;
946 }
947 /* numsrc >= (1G-4) overflow in 32 bits */
948 if (msf->imsf_numsrc >= 0x3ffffffcU ||
949 msf->imsf_numsrc > net->ipv4.sysctl_igmp_max_msf) {
950 kfree(msf);
951 err = -ENOBUFS;
952 break;
953 }
954 if (IP_MSFILTER_SIZE(msf->imsf_numsrc) > optlen) {
955 kfree(msf);
956 err = -EINVAL;
957 break;
958 }
959 err = ip_mc_msfilter(sk, msf, 0);
960 kfree(msf);
961 break;
962 }
963 case IP_BLOCK_SOURCE:
964 case IP_UNBLOCK_SOURCE:
965 case IP_ADD_SOURCE_MEMBERSHIP:
966 case IP_DROP_SOURCE_MEMBERSHIP:
967 {
968 struct ip_mreq_source mreqs;
969 int omode, add;
970
971 if (optlen != sizeof(struct ip_mreq_source))
972 goto e_inval;
973 if (copy_from_user(&mreqs, optval, sizeof(mreqs))) {
974 err = -EFAULT;
975 break;
976 }
977 if (optname == IP_BLOCK_SOURCE) {
978 omode = MCAST_EXCLUDE;
979 add = 1;
980 } else if (optname == IP_UNBLOCK_SOURCE) {
981 omode = MCAST_EXCLUDE;
982 add = 0;
983 } else if (optname == IP_ADD_SOURCE_MEMBERSHIP) {
984 struct ip_mreqn mreq;
985
986 mreq.imr_multiaddr.s_addr = mreqs.imr_multiaddr;
987 mreq.imr_address.s_addr = mreqs.imr_interface;
988 mreq.imr_ifindex = 0;
989 err = ip_mc_join_group_ssm(sk, &mreq, MCAST_INCLUDE);
990 if (err && err != -EADDRINUSE)
991 break;
992 omode = MCAST_INCLUDE;
993 add = 1;
994 } else /* IP_DROP_SOURCE_MEMBERSHIP */ {
995 omode = MCAST_INCLUDE;
996 add = 0;
997 }
998 err = ip_mc_source(add, omode, sk, &mreqs, 0);
999 break;
1000 }
1001 case MCAST_JOIN_GROUP:
1002 case MCAST_LEAVE_GROUP:
1003 {
1004 struct group_req greq;
1005 struct sockaddr_in *psin;
1006 struct ip_mreqn mreq;
1007
1008 if (optlen < sizeof(struct group_req))
1009 goto e_inval;
1010 err = -EFAULT;
1011 if (copy_from_user(&greq, optval, sizeof(greq)))
1012 break;
1013 psin = (struct sockaddr_in *)&greq.gr_group;
1014 if (psin->sin_family != AF_INET)
1015 goto e_inval;
1016 memset(&mreq, 0, sizeof(mreq));
1017 mreq.imr_multiaddr = psin->sin_addr;
1018 mreq.imr_ifindex = greq.gr_interface;
1019
1020 if (optname == MCAST_JOIN_GROUP)
1021 err = ip_mc_join_group(sk, &mreq);
1022 else
1023 err = ip_mc_leave_group(sk, &mreq);
1024 break;
1025 }
1026 case MCAST_JOIN_SOURCE_GROUP:
1027 case MCAST_LEAVE_SOURCE_GROUP:
1028 case MCAST_BLOCK_SOURCE:
1029 case MCAST_UNBLOCK_SOURCE:
1030 {
1031 struct group_source_req greqs;
1032 struct ip_mreq_source mreqs;
1033 struct sockaddr_in *psin;
1034 int omode, add;
1035
1036 if (optlen != sizeof(struct group_source_req))
1037 goto e_inval;
1038 if (copy_from_user(&greqs, optval, sizeof(greqs))) {
1039 err = -EFAULT;
1040 break;
1041 }
1042 if (greqs.gsr_group.ss_family != AF_INET ||
1043 greqs.gsr_source.ss_family != AF_INET) {
1044 err = -EADDRNOTAVAIL;
1045 break;
1046 }
1047 psin = (struct sockaddr_in *)&greqs.gsr_group;
1048 mreqs.imr_multiaddr = psin->sin_addr.s_addr;
1049 psin = (struct sockaddr_in *)&greqs.gsr_source;
1050 mreqs.imr_sourceaddr = psin->sin_addr.s_addr;
1051 mreqs.imr_interface = 0; /* use index for mc_source */
1052
1053 if (optname == MCAST_BLOCK_SOURCE) {
1054 omode = MCAST_EXCLUDE;
1055 add = 1;
1056 } else if (optname == MCAST_UNBLOCK_SOURCE) {
1057 omode = MCAST_EXCLUDE;
1058 add = 0;
1059 } else if (optname == MCAST_JOIN_SOURCE_GROUP) {
1060 struct ip_mreqn mreq;
1061
1062 psin = (struct sockaddr_in *)&greqs.gsr_group;
1063 mreq.imr_multiaddr = psin->sin_addr;
1064 mreq.imr_address.s_addr = 0;
1065 mreq.imr_ifindex = greqs.gsr_interface;
1066 err = ip_mc_join_group_ssm(sk, &mreq, MCAST_INCLUDE);
1067 if (err && err != -EADDRINUSE)
1068 break;
1069 greqs.gsr_interface = mreq.imr_ifindex;
1070 omode = MCAST_INCLUDE;
1071 add = 1;
1072 } else /* MCAST_LEAVE_SOURCE_GROUP */ {
1073 omode = MCAST_INCLUDE;
1074 add = 0;
1075 }
1076 err = ip_mc_source(add, omode, sk, &mreqs,
1077 greqs.gsr_interface);
1078 break;
1079 }
1080 case MCAST_MSFILTER:
1081 {
1082 struct sockaddr_in *psin;
1083 struct ip_msfilter *msf = NULL;
1084 struct group_filter *gsf = NULL;
1085 int msize, i, ifindex;
1086
1087 if (optlen < GROUP_FILTER_SIZE(0))
1088 goto e_inval;
1089 if (optlen > sysctl_optmem_max) {
1090 err = -ENOBUFS;
1091 break;
1092 }
1093 gsf = memdup_user(optval, optlen);
1094 if (IS_ERR(gsf)) {
1095 err = PTR_ERR(gsf);
1096 break;
1097 }
1098
1099 /* numsrc >= (4G-140)/128 overflow in 32 bits */
1100 if (gsf->gf_numsrc >= 0x1ffffff ||
1101 gsf->gf_numsrc > net->ipv4.sysctl_igmp_max_msf) {
1102 err = -ENOBUFS;
1103 goto mc_msf_out;
1104 }
1105 if (GROUP_FILTER_SIZE(gsf->gf_numsrc) > optlen) {
1106 err = -EINVAL;
1107 goto mc_msf_out;
1108 }
1109 msize = IP_MSFILTER_SIZE(gsf->gf_numsrc);
1110 msf = kmalloc(msize, GFP_KERNEL);
1111 if (!msf) {
1112 err = -ENOBUFS;
1113 goto mc_msf_out;
1114 }
1115 ifindex = gsf->gf_interface;
1116 psin = (struct sockaddr_in *)&gsf->gf_group;
1117 if (psin->sin_family != AF_INET) {
1118 err = -EADDRNOTAVAIL;
1119 goto mc_msf_out;
1120 }
1121 msf->imsf_multiaddr = psin->sin_addr.s_addr;
1122 msf->imsf_interface = 0;
1123 msf->imsf_fmode = gsf->gf_fmode;
1124 msf->imsf_numsrc = gsf->gf_numsrc;
1125 err = -EADDRNOTAVAIL;
1126 for (i = 0; i < gsf->gf_numsrc; ++i) {
1127 psin = (struct sockaddr_in *)&gsf->gf_slist[i];
1128
1129 if (psin->sin_family != AF_INET)
1130 goto mc_msf_out;
1131 msf->imsf_slist[i] = psin->sin_addr.s_addr;
1132 }
1133 kfree(gsf);
1134 gsf = NULL;
1135
1136 err = ip_mc_msfilter(sk, msf, ifindex);
1137 mc_msf_out:
1138 kfree(msf);
1139 kfree(gsf);
1140 break;
1141 }
1142 case IP_MULTICAST_ALL:
1143 if (optlen < 1)
1144 goto e_inval;
1145 if (val != 0 && val != 1)
1146 goto e_inval;
1147 inet->mc_all = val;
1148 break;
1149
1150 case IP_FREEBIND:
1151 if (optlen < 1)
1152 goto e_inval;
1153 inet->freebind = !!val;
1154 break;
1155
1156 case IP_IPSEC_POLICY:
1157 case IP_XFRM_POLICY:
1158 err = -EPERM;
1159 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1160 break;
1161 err = xfrm_user_policy(sk, optname, optval, optlen);
1162 break;
1163
1164 case IP_TRANSPARENT:
1165 if (!!val && !ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
1166 !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1167 err = -EPERM;
1168 break;
1169 }
1170 if (optlen < 1)
1171 goto e_inval;
1172 inet->transparent = !!val;
1173 break;
1174
1175 case IP_MINTTL:
1176 if (optlen < 1)
1177 goto e_inval;
1178 if (val < 0 || val > 255)
1179 goto e_inval;
1180 inet->min_ttl = val;
1181 break;
1182
1183 default:
1184 err = -ENOPROTOOPT;
1185 break;
1186 }
1187 release_sock(sk);
1188 if (needs_rtnl)
1189 rtnl_unlock();
1190 return err;
1191
1192 e_inval:
1193 release_sock(sk);
1194 if (needs_rtnl)
1195 rtnl_unlock();
1196 return -EINVAL;
1197 }
1198
1199 /**
1200 * ipv4_pktinfo_prepare - transfer some info from rtable to skb
1201 * @sk: socket
1202 * @skb: buffer
1203 *
1204 * To support IP_CMSG_PKTINFO option, we store rt_iif and specific
1205 * destination in skb->cb[] before dst drop.
1206 * This way, receiver doesn't make cache line misses to read rtable.
1207 */
ipv4_pktinfo_prepare(const struct sock * sk,struct sk_buff * skb)1208 void ipv4_pktinfo_prepare(const struct sock *sk, struct sk_buff *skb)
1209 {
1210 struct in_pktinfo *pktinfo = PKTINFO_SKB_CB(skb);
1211 bool prepare = (inet_sk(sk)->cmsg_flags & IP_CMSG_PKTINFO) ||
1212 ipv6_sk_rxinfo(sk);
1213
1214 if (prepare && skb_rtable(skb)) {
1215 /* skb->cb is overloaded: prior to this point it is IP{6}CB
1216 * which has interface index (iif) as the first member of the
1217 * underlying inet{6}_skb_parm struct. This code then overlays
1218 * PKTINFO_SKB_CB and in_pktinfo also has iif as the first
1219 * element so the iif is picked up from the prior IPCB. If iif
1220 * is the loopback interface, then return the sending interface
1221 * (e.g., process binds socket to eth0 for Tx which is
1222 * redirected to loopback in the rtable/dst).
1223 */
1224 struct rtable *rt = skb_rtable(skb);
1225 bool l3slave = ipv4_l3mdev_skb(IPCB(skb)->flags);
1226
1227 if (pktinfo->ipi_ifindex == LOOPBACK_IFINDEX)
1228 pktinfo->ipi_ifindex = inet_iif(skb);
1229 else if (l3slave && rt && rt->rt_iif)
1230 pktinfo->ipi_ifindex = rt->rt_iif;
1231
1232 pktinfo->ipi_spec_dst.s_addr = fib_compute_spec_dst(skb);
1233 } else {
1234 pktinfo->ipi_ifindex = 0;
1235 pktinfo->ipi_spec_dst.s_addr = 0;
1236 }
1237 skb_dst_drop(skb);
1238 }
1239
ip_setsockopt(struct sock * sk,int level,int optname,char __user * optval,unsigned int optlen)1240 int ip_setsockopt(struct sock *sk, int level,
1241 int optname, char __user *optval, unsigned int optlen)
1242 {
1243 int err;
1244
1245 if (level != SOL_IP)
1246 return -ENOPROTOOPT;
1247
1248 err = do_ip_setsockopt(sk, level, optname, optval, optlen);
1249 #if IS_ENABLED(CONFIG_BPFILTER_UMH)
1250 if (optname >= BPFILTER_IPT_SO_SET_REPLACE &&
1251 optname < BPFILTER_IPT_SET_MAX)
1252 err = bpfilter_ip_set_sockopt(sk, optname, optval, optlen);
1253 #endif
1254 #ifdef CONFIG_NETFILTER
1255 /* we need to exclude all possible ENOPROTOOPTs except default case */
1256 if (err == -ENOPROTOOPT && optname != IP_HDRINCL &&
1257 optname != IP_IPSEC_POLICY &&
1258 optname != IP_XFRM_POLICY &&
1259 !ip_mroute_opt(optname))
1260 err = nf_setsockopt(sk, PF_INET, optname, optval, optlen);
1261 #endif
1262 return err;
1263 }
1264 EXPORT_SYMBOL(ip_setsockopt);
1265
1266 #ifdef CONFIG_COMPAT
compat_ip_setsockopt(struct sock * sk,int level,int optname,char __user * optval,unsigned int optlen)1267 int compat_ip_setsockopt(struct sock *sk, int level, int optname,
1268 char __user *optval, unsigned int optlen)
1269 {
1270 int err;
1271
1272 if (level != SOL_IP)
1273 return -ENOPROTOOPT;
1274
1275 if (optname >= MCAST_JOIN_GROUP && optname <= MCAST_MSFILTER)
1276 return compat_mc_setsockopt(sk, level, optname, optval, optlen,
1277 ip_setsockopt);
1278
1279 err = do_ip_setsockopt(sk, level, optname, optval, optlen);
1280 #ifdef CONFIG_NETFILTER
1281 /* we need to exclude all possible ENOPROTOOPTs except default case */
1282 if (err == -ENOPROTOOPT && optname != IP_HDRINCL &&
1283 optname != IP_IPSEC_POLICY &&
1284 optname != IP_XFRM_POLICY &&
1285 !ip_mroute_opt(optname))
1286 err = compat_nf_setsockopt(sk, PF_INET, optname, optval,
1287 optlen);
1288 #endif
1289 return err;
1290 }
1291 EXPORT_SYMBOL(compat_ip_setsockopt);
1292 #endif
1293
1294 /*
1295 * Get the options. Note for future reference. The GET of IP options gets
1296 * the _received_ ones. The set sets the _sent_ ones.
1297 */
1298
getsockopt_needs_rtnl(int optname)1299 static bool getsockopt_needs_rtnl(int optname)
1300 {
1301 switch (optname) {
1302 case IP_MSFILTER:
1303 case MCAST_MSFILTER:
1304 return true;
1305 }
1306 return false;
1307 }
1308
do_ip_getsockopt(struct sock * sk,int level,int optname,char __user * optval,int __user * optlen,unsigned int flags)1309 static int do_ip_getsockopt(struct sock *sk, int level, int optname,
1310 char __user *optval, int __user *optlen, unsigned int flags)
1311 {
1312 struct inet_sock *inet = inet_sk(sk);
1313 bool needs_rtnl = getsockopt_needs_rtnl(optname);
1314 int val, err = 0;
1315 int len;
1316
1317 if (level != SOL_IP)
1318 return -EOPNOTSUPP;
1319
1320 if (ip_mroute_opt(optname))
1321 return ip_mroute_getsockopt(sk, optname, optval, optlen);
1322
1323 if (get_user(len, optlen))
1324 return -EFAULT;
1325 if (len < 0)
1326 return -EINVAL;
1327
1328 if (needs_rtnl)
1329 rtnl_lock();
1330 lock_sock(sk);
1331
1332 switch (optname) {
1333 case IP_OPTIONS:
1334 {
1335 unsigned char optbuf[sizeof(struct ip_options)+40];
1336 struct ip_options *opt = (struct ip_options *)optbuf;
1337 struct ip_options_rcu *inet_opt;
1338
1339 inet_opt = rcu_dereference_protected(inet->inet_opt,
1340 lockdep_sock_is_held(sk));
1341 opt->optlen = 0;
1342 if (inet_opt)
1343 memcpy(optbuf, &inet_opt->opt,
1344 sizeof(struct ip_options) +
1345 inet_opt->opt.optlen);
1346 release_sock(sk);
1347
1348 if (opt->optlen == 0)
1349 return put_user(0, optlen);
1350
1351 ip_options_undo(opt);
1352
1353 len = min_t(unsigned int, len, opt->optlen);
1354 if (put_user(len, optlen))
1355 return -EFAULT;
1356 if (copy_to_user(optval, opt->__data, len))
1357 return -EFAULT;
1358 return 0;
1359 }
1360 case IP_PKTINFO:
1361 val = (inet->cmsg_flags & IP_CMSG_PKTINFO) != 0;
1362 break;
1363 case IP_RECVTTL:
1364 val = (inet->cmsg_flags & IP_CMSG_TTL) != 0;
1365 break;
1366 case IP_RECVTOS:
1367 val = (inet->cmsg_flags & IP_CMSG_TOS) != 0;
1368 break;
1369 case IP_RECVOPTS:
1370 val = (inet->cmsg_flags & IP_CMSG_RECVOPTS) != 0;
1371 break;
1372 case IP_RETOPTS:
1373 val = (inet->cmsg_flags & IP_CMSG_RETOPTS) != 0;
1374 break;
1375 case IP_PASSSEC:
1376 val = (inet->cmsg_flags & IP_CMSG_PASSSEC) != 0;
1377 break;
1378 case IP_RECVORIGDSTADDR:
1379 val = (inet->cmsg_flags & IP_CMSG_ORIGDSTADDR) != 0;
1380 break;
1381 case IP_CHECKSUM:
1382 val = (inet->cmsg_flags & IP_CMSG_CHECKSUM) != 0;
1383 break;
1384 case IP_RECVFRAGSIZE:
1385 val = (inet->cmsg_flags & IP_CMSG_RECVFRAGSIZE) != 0;
1386 break;
1387 case IP_TOS:
1388 val = inet->tos;
1389 break;
1390 case IP_TTL:
1391 {
1392 struct net *net = sock_net(sk);
1393 val = (inet->uc_ttl == -1 ?
1394 net->ipv4.sysctl_ip_default_ttl :
1395 inet->uc_ttl);
1396 break;
1397 }
1398 case IP_HDRINCL:
1399 val = inet->hdrincl;
1400 break;
1401 case IP_NODEFRAG:
1402 val = inet->nodefrag;
1403 break;
1404 case IP_BIND_ADDRESS_NO_PORT:
1405 val = inet->bind_address_no_port;
1406 break;
1407 case IP_MTU_DISCOVER:
1408 val = inet->pmtudisc;
1409 break;
1410 case IP_MTU:
1411 {
1412 struct dst_entry *dst;
1413 val = 0;
1414 dst = sk_dst_get(sk);
1415 if (dst) {
1416 val = dst_mtu(dst);
1417 dst_release(dst);
1418 }
1419 if (!val) {
1420 release_sock(sk);
1421 return -ENOTCONN;
1422 }
1423 break;
1424 }
1425 case IP_RECVERR:
1426 val = inet->recverr;
1427 break;
1428 case IP_MULTICAST_TTL:
1429 val = inet->mc_ttl;
1430 break;
1431 case IP_MULTICAST_LOOP:
1432 val = inet->mc_loop;
1433 break;
1434 case IP_UNICAST_IF:
1435 val = (__force int)htonl((__u32) inet->uc_index);
1436 break;
1437 case IP_MULTICAST_IF:
1438 {
1439 struct in_addr addr;
1440 len = min_t(unsigned int, len, sizeof(struct in_addr));
1441 addr.s_addr = inet->mc_addr;
1442 release_sock(sk);
1443
1444 if (put_user(len, optlen))
1445 return -EFAULT;
1446 if (copy_to_user(optval, &addr, len))
1447 return -EFAULT;
1448 return 0;
1449 }
1450 case IP_MSFILTER:
1451 {
1452 struct ip_msfilter msf;
1453
1454 if (len < IP_MSFILTER_SIZE(0)) {
1455 err = -EINVAL;
1456 goto out;
1457 }
1458 if (copy_from_user(&msf, optval, IP_MSFILTER_SIZE(0))) {
1459 err = -EFAULT;
1460 goto out;
1461 }
1462 err = ip_mc_msfget(sk, &msf,
1463 (struct ip_msfilter __user *)optval, optlen);
1464 goto out;
1465 }
1466 case MCAST_MSFILTER:
1467 {
1468 struct group_filter gsf;
1469
1470 if (len < GROUP_FILTER_SIZE(0)) {
1471 err = -EINVAL;
1472 goto out;
1473 }
1474 if (copy_from_user(&gsf, optval, GROUP_FILTER_SIZE(0))) {
1475 err = -EFAULT;
1476 goto out;
1477 }
1478 err = ip_mc_gsfget(sk, &gsf,
1479 (struct group_filter __user *)optval,
1480 optlen);
1481 goto out;
1482 }
1483 case IP_MULTICAST_ALL:
1484 val = inet->mc_all;
1485 break;
1486 case IP_PKTOPTIONS:
1487 {
1488 struct msghdr msg;
1489
1490 release_sock(sk);
1491
1492 if (sk->sk_type != SOCK_STREAM)
1493 return -ENOPROTOOPT;
1494
1495 msg.msg_control = (__force void *) optval;
1496 msg.msg_controllen = len;
1497 msg.msg_flags = flags;
1498
1499 if (inet->cmsg_flags & IP_CMSG_PKTINFO) {
1500 struct in_pktinfo info;
1501
1502 info.ipi_addr.s_addr = inet->inet_rcv_saddr;
1503 info.ipi_spec_dst.s_addr = inet->inet_rcv_saddr;
1504 info.ipi_ifindex = inet->mc_index;
1505 put_cmsg(&msg, SOL_IP, IP_PKTINFO, sizeof(info), &info);
1506 }
1507 if (inet->cmsg_flags & IP_CMSG_TTL) {
1508 int hlim = inet->mc_ttl;
1509 put_cmsg(&msg, SOL_IP, IP_TTL, sizeof(hlim), &hlim);
1510 }
1511 if (inet->cmsg_flags & IP_CMSG_TOS) {
1512 int tos = inet->rcv_tos;
1513 put_cmsg(&msg, SOL_IP, IP_TOS, sizeof(tos), &tos);
1514 }
1515 len -= msg.msg_controllen;
1516 return put_user(len, optlen);
1517 }
1518 case IP_FREEBIND:
1519 val = inet->freebind;
1520 break;
1521 case IP_TRANSPARENT:
1522 val = inet->transparent;
1523 break;
1524 case IP_MINTTL:
1525 val = inet->min_ttl;
1526 break;
1527 default:
1528 release_sock(sk);
1529 return -ENOPROTOOPT;
1530 }
1531 release_sock(sk);
1532
1533 if (len < sizeof(int) && len > 0 && val >= 0 && val <= 255) {
1534 unsigned char ucval = (unsigned char)val;
1535 len = 1;
1536 if (put_user(len, optlen))
1537 return -EFAULT;
1538 if (copy_to_user(optval, &ucval, 1))
1539 return -EFAULT;
1540 } else {
1541 len = min_t(unsigned int, sizeof(int), len);
1542 if (put_user(len, optlen))
1543 return -EFAULT;
1544 if (copy_to_user(optval, &val, len))
1545 return -EFAULT;
1546 }
1547 return 0;
1548
1549 out:
1550 release_sock(sk);
1551 if (needs_rtnl)
1552 rtnl_unlock();
1553 return err;
1554 }
1555
ip_getsockopt(struct sock * sk,int level,int optname,char __user * optval,int __user * optlen)1556 int ip_getsockopt(struct sock *sk, int level,
1557 int optname, char __user *optval, int __user *optlen)
1558 {
1559 int err;
1560
1561 err = do_ip_getsockopt(sk, level, optname, optval, optlen, 0);
1562 #if IS_ENABLED(CONFIG_BPFILTER_UMH)
1563 if (optname >= BPFILTER_IPT_SO_GET_INFO &&
1564 optname < BPFILTER_IPT_GET_MAX)
1565 err = bpfilter_ip_get_sockopt(sk, optname, optval, optlen);
1566 #endif
1567 #ifdef CONFIG_NETFILTER
1568 /* we need to exclude all possible ENOPROTOOPTs except default case */
1569 if (err == -ENOPROTOOPT && optname != IP_PKTOPTIONS &&
1570 !ip_mroute_opt(optname)) {
1571 int len;
1572
1573 if (get_user(len, optlen))
1574 return -EFAULT;
1575
1576 err = nf_getsockopt(sk, PF_INET, optname, optval, &len);
1577 if (err >= 0)
1578 err = put_user(len, optlen);
1579 return err;
1580 }
1581 #endif
1582 return err;
1583 }
1584 EXPORT_SYMBOL(ip_getsockopt);
1585
1586 #ifdef CONFIG_COMPAT
compat_ip_getsockopt(struct sock * sk,int level,int optname,char __user * optval,int __user * optlen)1587 int compat_ip_getsockopt(struct sock *sk, int level, int optname,
1588 char __user *optval, int __user *optlen)
1589 {
1590 int err;
1591
1592 if (optname == MCAST_MSFILTER)
1593 return compat_mc_getsockopt(sk, level, optname, optval, optlen,
1594 ip_getsockopt);
1595
1596 err = do_ip_getsockopt(sk, level, optname, optval, optlen,
1597 MSG_CMSG_COMPAT);
1598
1599 #if IS_ENABLED(CONFIG_BPFILTER_UMH)
1600 if (optname >= BPFILTER_IPT_SO_GET_INFO &&
1601 optname < BPFILTER_IPT_GET_MAX)
1602 err = bpfilter_ip_get_sockopt(sk, optname, optval, optlen);
1603 #endif
1604 #ifdef CONFIG_NETFILTER
1605 /* we need to exclude all possible ENOPROTOOPTs except default case */
1606 if (err == -ENOPROTOOPT && optname != IP_PKTOPTIONS &&
1607 !ip_mroute_opt(optname)) {
1608 int len;
1609
1610 if (get_user(len, optlen))
1611 return -EFAULT;
1612
1613 err = compat_nf_getsockopt(sk, PF_INET, optname, optval, &len);
1614 if (err >= 0)
1615 err = put_user(len, optlen);
1616 return err;
1617 }
1618 #endif
1619 return err;
1620 }
1621 EXPORT_SYMBOL(compat_ip_getsockopt);
1622 #endif
1623