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 #if IS_ENABLED(CONFIG_IPV6)
41 #include <net/transp_v6.h>
42 #endif
43 #include <net/ip_fib.h>
44
45 #include <linux/errqueue.h>
46 #include <asm/uaccess.h>
47
48 #define IP_CMSG_PKTINFO 1
49 #define IP_CMSG_TTL 2
50 #define IP_CMSG_TOS 4
51 #define IP_CMSG_RECVOPTS 8
52 #define IP_CMSG_RETOPTS 16
53 #define IP_CMSG_PASSSEC 32
54 #define IP_CMSG_ORIGDSTADDR 64
55
56 /*
57 * SOL_IP control messages.
58 */
59
ip_cmsg_recv_pktinfo(struct msghdr * msg,struct sk_buff * skb)60 static void ip_cmsg_recv_pktinfo(struct msghdr *msg, struct sk_buff *skb)
61 {
62 struct in_pktinfo info = *PKTINFO_SKB_CB(skb);
63
64 info.ipi_addr.s_addr = ip_hdr(skb)->daddr;
65
66 put_cmsg(msg, SOL_IP, IP_PKTINFO, sizeof(info), &info);
67 }
68
ip_cmsg_recv_ttl(struct msghdr * msg,struct sk_buff * skb)69 static void ip_cmsg_recv_ttl(struct msghdr *msg, struct sk_buff *skb)
70 {
71 int ttl = ip_hdr(skb)->ttl;
72 put_cmsg(msg, SOL_IP, IP_TTL, sizeof(int), &ttl);
73 }
74
ip_cmsg_recv_tos(struct msghdr * msg,struct sk_buff * skb)75 static void ip_cmsg_recv_tos(struct msghdr *msg, struct sk_buff *skb)
76 {
77 put_cmsg(msg, SOL_IP, IP_TOS, 1, &ip_hdr(skb)->tos);
78 }
79
ip_cmsg_recv_opts(struct msghdr * msg,struct sk_buff * skb)80 static void ip_cmsg_recv_opts(struct msghdr *msg, struct sk_buff *skb)
81 {
82 if (IPCB(skb)->opt.optlen == 0)
83 return;
84
85 put_cmsg(msg, SOL_IP, IP_RECVOPTS, IPCB(skb)->opt.optlen,
86 ip_hdr(skb) + 1);
87 }
88
89
ip_cmsg_recv_retopts(struct msghdr * msg,struct sk_buff * skb)90 static void ip_cmsg_recv_retopts(struct msghdr *msg, struct sk_buff *skb)
91 {
92 unsigned char optbuf[sizeof(struct ip_options) + 40];
93 struct ip_options *opt = (struct ip_options *)optbuf;
94
95 if (IPCB(skb)->opt.optlen == 0)
96 return;
97
98 if (ip_options_echo(opt, skb)) {
99 msg->msg_flags |= MSG_CTRUNC;
100 return;
101 }
102 ip_options_undo(opt);
103
104 put_cmsg(msg, SOL_IP, IP_RETOPTS, opt->optlen, opt->__data);
105 }
106
ip_cmsg_recv_security(struct msghdr * msg,struct sk_buff * skb)107 static void ip_cmsg_recv_security(struct msghdr *msg, struct sk_buff *skb)
108 {
109 char *secdata;
110 u32 seclen, secid;
111 int err;
112
113 err = security_socket_getpeersec_dgram(NULL, skb, &secid);
114 if (err)
115 return;
116
117 err = security_secid_to_secctx(secid, &secdata, &seclen);
118 if (err)
119 return;
120
121 put_cmsg(msg, SOL_IP, SCM_SECURITY, seclen, secdata);
122 security_release_secctx(secdata, seclen);
123 }
124
ip_cmsg_recv_dstaddr(struct msghdr * msg,struct sk_buff * skb)125 static void ip_cmsg_recv_dstaddr(struct msghdr *msg, struct sk_buff *skb)
126 {
127 struct sockaddr_in sin;
128 const struct iphdr *iph = ip_hdr(skb);
129 __be16 *ports = (__be16 *)skb_transport_header(skb);
130
131 if (skb_transport_offset(skb) + 4 > skb->len)
132 return;
133
134 /* All current transport protocols have the port numbers in the
135 * first four bytes of the transport header and this function is
136 * written with this assumption in mind.
137 */
138
139 sin.sin_family = AF_INET;
140 sin.sin_addr.s_addr = iph->daddr;
141 sin.sin_port = ports[1];
142 memset(sin.sin_zero, 0, sizeof(sin.sin_zero));
143
144 put_cmsg(msg, SOL_IP, IP_ORIGDSTADDR, sizeof(sin), &sin);
145 }
146
ip_cmsg_recv(struct msghdr * msg,struct sk_buff * skb)147 void ip_cmsg_recv(struct msghdr *msg, struct sk_buff *skb)
148 {
149 struct inet_sock *inet = inet_sk(skb->sk);
150 unsigned int flags = inet->cmsg_flags;
151
152 /* Ordered by supposed usage frequency */
153 if (flags & 1)
154 ip_cmsg_recv_pktinfo(msg, skb);
155 if ((flags >>= 1) == 0)
156 return;
157
158 if (flags & 1)
159 ip_cmsg_recv_ttl(msg, skb);
160 if ((flags >>= 1) == 0)
161 return;
162
163 if (flags & 1)
164 ip_cmsg_recv_tos(msg, skb);
165 if ((flags >>= 1) == 0)
166 return;
167
168 if (flags & 1)
169 ip_cmsg_recv_opts(msg, skb);
170 if ((flags >>= 1) == 0)
171 return;
172
173 if (flags & 1)
174 ip_cmsg_recv_retopts(msg, skb);
175 if ((flags >>= 1) == 0)
176 return;
177
178 if (flags & 1)
179 ip_cmsg_recv_security(msg, skb);
180
181 if ((flags >>= 1) == 0)
182 return;
183 if (flags & 1)
184 ip_cmsg_recv_dstaddr(msg, skb);
185
186 }
187 EXPORT_SYMBOL(ip_cmsg_recv);
188
ip_cmsg_send(struct net * net,struct msghdr * msg,struct ipcm_cookie * ipc,bool allow_ipv6)189 int ip_cmsg_send(struct net *net, struct msghdr *msg, struct ipcm_cookie *ipc,
190 bool allow_ipv6)
191 {
192 int err, val;
193 struct cmsghdr *cmsg;
194
195 for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
196 if (!CMSG_OK(msg, cmsg))
197 return -EINVAL;
198 #if IS_ENABLED(CONFIG_IPV6)
199 if (allow_ipv6 &&
200 cmsg->cmsg_level == SOL_IPV6 &&
201 cmsg->cmsg_type == IPV6_PKTINFO) {
202 struct in6_pktinfo *src_info;
203
204 if (cmsg->cmsg_len < CMSG_LEN(sizeof(*src_info)))
205 return -EINVAL;
206 src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg);
207 if (!ipv6_addr_v4mapped(&src_info->ipi6_addr))
208 return -EINVAL;
209 ipc->oif = src_info->ipi6_ifindex;
210 ipc->addr = src_info->ipi6_addr.s6_addr32[3];
211 continue;
212 }
213 #endif
214 if (cmsg->cmsg_level != SOL_IP)
215 continue;
216 switch (cmsg->cmsg_type) {
217 case IP_RETOPTS:
218 err = cmsg->cmsg_len - CMSG_ALIGN(sizeof(struct cmsghdr));
219 err = ip_options_get(net, &ipc->opt, CMSG_DATA(cmsg),
220 err < 40 ? err : 40);
221 if (err)
222 return err;
223 break;
224 case IP_PKTINFO:
225 {
226 struct in_pktinfo *info;
227 if (cmsg->cmsg_len != CMSG_LEN(sizeof(struct in_pktinfo)))
228 return -EINVAL;
229 info = (struct in_pktinfo *)CMSG_DATA(cmsg);
230 ipc->oif = info->ipi_ifindex;
231 ipc->addr = info->ipi_spec_dst.s_addr;
232 break;
233 }
234 case IP_TTL:
235 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
236 return -EINVAL;
237 val = *(int *)CMSG_DATA(cmsg);
238 if (val < 1 || val > 255)
239 return -EINVAL;
240 ipc->ttl = val;
241 break;
242 case IP_TOS:
243 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
244 return -EINVAL;
245 val = *(int *)CMSG_DATA(cmsg);
246 if (val < 0 || val > 255)
247 return -EINVAL;
248 ipc->tos = val;
249 ipc->priority = rt_tos2priority(ipc->tos);
250 break;
251
252 default:
253 return -EINVAL;
254 }
255 }
256 return 0;
257 }
258
259
260 /* Special input handler for packets caught by router alert option.
261 They are selected only by protocol field, and then processed likely
262 local ones; but only if someone wants them! Otherwise, router
263 not running rsvpd will kill RSVP.
264
265 It is user level problem, what it will make with them.
266 I have no idea, how it will masquearde or NAT them (it is joke, joke :-)),
267 but receiver should be enough clever f.e. to forward mtrace requests,
268 sent to multicast group to reach destination designated router.
269 */
270 struct ip_ra_chain __rcu *ip_ra_chain;
271 static DEFINE_SPINLOCK(ip_ra_lock);
272
273
ip_ra_destroy_rcu(struct rcu_head * head)274 static void ip_ra_destroy_rcu(struct rcu_head *head)
275 {
276 struct ip_ra_chain *ra = container_of(head, struct ip_ra_chain, rcu);
277
278 sock_put(ra->saved_sk);
279 kfree(ra);
280 }
281
ip_ra_control(struct sock * sk,unsigned char on,void (* destructor)(struct sock *))282 int ip_ra_control(struct sock *sk, unsigned char on,
283 void (*destructor)(struct sock *))
284 {
285 struct ip_ra_chain *ra, *new_ra;
286 struct ip_ra_chain __rcu **rap;
287
288 if (sk->sk_type != SOCK_RAW || inet_sk(sk)->inet_num == IPPROTO_RAW)
289 return -EINVAL;
290
291 new_ra = on ? kmalloc(sizeof(*new_ra), GFP_KERNEL) : NULL;
292
293 spin_lock_bh(&ip_ra_lock);
294 for (rap = &ip_ra_chain;
295 (ra = rcu_dereference_protected(*rap,
296 lockdep_is_held(&ip_ra_lock))) != NULL;
297 rap = &ra->next) {
298 if (ra->sk == sk) {
299 if (on) {
300 spin_unlock_bh(&ip_ra_lock);
301 kfree(new_ra);
302 return -EADDRINUSE;
303 }
304 /* dont let ip_call_ra_chain() use sk again */
305 ra->sk = NULL;
306 RCU_INIT_POINTER(*rap, ra->next);
307 spin_unlock_bh(&ip_ra_lock);
308
309 if (ra->destructor)
310 ra->destructor(sk);
311 /*
312 * Delay sock_put(sk) and kfree(ra) after one rcu grace
313 * period. This guarantee ip_call_ra_chain() dont need
314 * to mess with socket refcounts.
315 */
316 ra->saved_sk = sk;
317 call_rcu(&ra->rcu, ip_ra_destroy_rcu);
318 return 0;
319 }
320 }
321 if (new_ra == NULL) {
322 spin_unlock_bh(&ip_ra_lock);
323 return -ENOBUFS;
324 }
325 new_ra->sk = sk;
326 new_ra->destructor = destructor;
327
328 RCU_INIT_POINTER(new_ra->next, ra);
329 rcu_assign_pointer(*rap, new_ra);
330 sock_hold(sk);
331 spin_unlock_bh(&ip_ra_lock);
332
333 return 0;
334 }
335
ip_icmp_error(struct sock * sk,struct sk_buff * skb,int err,__be16 port,u32 info,u8 * payload)336 void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
337 __be16 port, u32 info, u8 *payload)
338 {
339 struct sock_exterr_skb *serr;
340
341 skb = skb_clone(skb, GFP_ATOMIC);
342 if (!skb)
343 return;
344
345 serr = SKB_EXT_ERR(skb);
346 serr->ee.ee_errno = err;
347 serr->ee.ee_origin = SO_EE_ORIGIN_ICMP;
348 serr->ee.ee_type = icmp_hdr(skb)->type;
349 serr->ee.ee_code = icmp_hdr(skb)->code;
350 serr->ee.ee_pad = 0;
351 serr->ee.ee_info = info;
352 serr->ee.ee_data = 0;
353 serr->addr_offset = (u8 *)&(((struct iphdr *)(icmp_hdr(skb) + 1))->daddr) -
354 skb_network_header(skb);
355 serr->port = port;
356
357 if (skb_pull(skb, payload - skb->data) != NULL) {
358 skb_reset_transport_header(skb);
359 if (sock_queue_err_skb(sk, skb) == 0)
360 return;
361 }
362 kfree_skb(skb);
363 }
364
ip_local_error(struct sock * sk,int err,__be32 daddr,__be16 port,u32 info)365 void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 port, u32 info)
366 {
367 struct inet_sock *inet = inet_sk(sk);
368 struct sock_exterr_skb *serr;
369 struct iphdr *iph;
370 struct sk_buff *skb;
371
372 if (!inet->recverr)
373 return;
374
375 skb = alloc_skb(sizeof(struct iphdr), GFP_ATOMIC);
376 if (!skb)
377 return;
378
379 skb_put(skb, sizeof(struct iphdr));
380 skb_reset_network_header(skb);
381 iph = ip_hdr(skb);
382 iph->daddr = daddr;
383
384 serr = SKB_EXT_ERR(skb);
385 serr->ee.ee_errno = err;
386 serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
387 serr->ee.ee_type = 0;
388 serr->ee.ee_code = 0;
389 serr->ee.ee_pad = 0;
390 serr->ee.ee_info = info;
391 serr->ee.ee_data = 0;
392 serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
393 serr->port = port;
394
395 __skb_pull(skb, skb_tail_pointer(skb) - skb->data);
396 skb_reset_transport_header(skb);
397
398 if (sock_queue_err_skb(sk, skb))
399 kfree_skb(skb);
400 }
401
402 /*
403 * Handle MSG_ERRQUEUE
404 */
ip_recv_error(struct sock * sk,struct msghdr * msg,int len,int * addr_len)405 int ip_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
406 {
407 struct sock_exterr_skb *serr;
408 struct sk_buff *skb;
409 DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name);
410 struct {
411 struct sock_extended_err ee;
412 struct sockaddr_in offender;
413 } errhdr;
414 int err;
415 int copied;
416
417 err = -EAGAIN;
418 skb = sock_dequeue_err_skb(sk);
419 if (skb == NULL)
420 goto out;
421
422 copied = skb->len;
423 if (copied > len) {
424 msg->msg_flags |= MSG_TRUNC;
425 copied = len;
426 }
427 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
428 if (err)
429 goto out_free_skb;
430
431 sock_recv_timestamp(msg, sk, skb);
432
433 serr = SKB_EXT_ERR(skb);
434
435 if (sin) {
436 sin->sin_family = AF_INET;
437 sin->sin_addr.s_addr = *(__be32 *)(skb_network_header(skb) +
438 serr->addr_offset);
439 sin->sin_port = serr->port;
440 memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
441 *addr_len = sizeof(*sin);
442 }
443
444 memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
445 sin = &errhdr.offender;
446 memset(sin, 0, sizeof(*sin));
447 if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP) {
448 sin->sin_family = AF_INET;
449 sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
450 if (inet_sk(sk)->cmsg_flags)
451 ip_cmsg_recv(msg, skb);
452 }
453
454 put_cmsg(msg, SOL_IP, IP_RECVERR, sizeof(errhdr), &errhdr);
455
456 /* Now we could try to dump offended packet options */
457
458 msg->msg_flags |= MSG_ERRQUEUE;
459 err = copied;
460
461 out_free_skb:
462 kfree_skb(skb);
463 out:
464 return err;
465 }
466
467
468 /*
469 * Socket option code for IP. This is the end of the line after any
470 * TCP,UDP etc options on an IP socket.
471 */
472
do_ip_setsockopt(struct sock * sk,int level,int optname,char __user * optval,unsigned int optlen)473 static int do_ip_setsockopt(struct sock *sk, int level,
474 int optname, char __user *optval, unsigned int optlen)
475 {
476 struct inet_sock *inet = inet_sk(sk);
477 int val = 0, err;
478
479 switch (optname) {
480 case IP_PKTINFO:
481 case IP_RECVTTL:
482 case IP_RECVOPTS:
483 case IP_RECVTOS:
484 case IP_RETOPTS:
485 case IP_TOS:
486 case IP_TTL:
487 case IP_HDRINCL:
488 case IP_MTU_DISCOVER:
489 case IP_RECVERR:
490 case IP_ROUTER_ALERT:
491 case IP_FREEBIND:
492 case IP_PASSSEC:
493 case IP_TRANSPARENT:
494 case IP_MINTTL:
495 case IP_NODEFRAG:
496 case IP_UNICAST_IF:
497 case IP_MULTICAST_TTL:
498 case IP_MULTICAST_ALL:
499 case IP_MULTICAST_LOOP:
500 case IP_RECVORIGDSTADDR:
501 if (optlen >= sizeof(int)) {
502 if (get_user(val, (int __user *) optval))
503 return -EFAULT;
504 } else if (optlen >= sizeof(char)) {
505 unsigned char ucval;
506
507 if (get_user(ucval, (unsigned char __user *) optval))
508 return -EFAULT;
509 val = (int) ucval;
510 }
511 }
512
513 /* If optlen==0, it is equivalent to val == 0 */
514
515 if (ip_mroute_opt(optname))
516 return ip_mroute_setsockopt(sk, optname, optval, optlen);
517
518 err = 0;
519 lock_sock(sk);
520
521 switch (optname) {
522 case IP_OPTIONS:
523 {
524 struct ip_options_rcu *old, *opt = NULL;
525
526 if (optlen > 40)
527 goto e_inval;
528 err = ip_options_get_from_user(sock_net(sk), &opt,
529 optval, optlen);
530 if (err)
531 break;
532 old = rcu_dereference_protected(inet->inet_opt,
533 sock_owned_by_user(sk));
534 if (inet->is_icsk) {
535 struct inet_connection_sock *icsk = inet_csk(sk);
536 #if IS_ENABLED(CONFIG_IPV6)
537 if (sk->sk_family == PF_INET ||
538 (!((1 << sk->sk_state) &
539 (TCPF_LISTEN | TCPF_CLOSE)) &&
540 inet->inet_daddr != LOOPBACK4_IPV6)) {
541 #endif
542 if (old)
543 icsk->icsk_ext_hdr_len -= old->opt.optlen;
544 if (opt)
545 icsk->icsk_ext_hdr_len += opt->opt.optlen;
546 icsk->icsk_sync_mss(sk, icsk->icsk_pmtu_cookie);
547 #if IS_ENABLED(CONFIG_IPV6)
548 }
549 #endif
550 }
551 rcu_assign_pointer(inet->inet_opt, opt);
552 if (old)
553 kfree_rcu(old, rcu);
554 break;
555 }
556 case IP_PKTINFO:
557 if (val)
558 inet->cmsg_flags |= IP_CMSG_PKTINFO;
559 else
560 inet->cmsg_flags &= ~IP_CMSG_PKTINFO;
561 break;
562 case IP_RECVTTL:
563 if (val)
564 inet->cmsg_flags |= IP_CMSG_TTL;
565 else
566 inet->cmsg_flags &= ~IP_CMSG_TTL;
567 break;
568 case IP_RECVTOS:
569 if (val)
570 inet->cmsg_flags |= IP_CMSG_TOS;
571 else
572 inet->cmsg_flags &= ~IP_CMSG_TOS;
573 break;
574 case IP_RECVOPTS:
575 if (val)
576 inet->cmsg_flags |= IP_CMSG_RECVOPTS;
577 else
578 inet->cmsg_flags &= ~IP_CMSG_RECVOPTS;
579 break;
580 case IP_RETOPTS:
581 if (val)
582 inet->cmsg_flags |= IP_CMSG_RETOPTS;
583 else
584 inet->cmsg_flags &= ~IP_CMSG_RETOPTS;
585 break;
586 case IP_PASSSEC:
587 if (val)
588 inet->cmsg_flags |= IP_CMSG_PASSSEC;
589 else
590 inet->cmsg_flags &= ~IP_CMSG_PASSSEC;
591 break;
592 case IP_RECVORIGDSTADDR:
593 if (val)
594 inet->cmsg_flags |= IP_CMSG_ORIGDSTADDR;
595 else
596 inet->cmsg_flags &= ~IP_CMSG_ORIGDSTADDR;
597 break;
598 case IP_TOS: /* This sets both TOS and Precedence */
599 if (sk->sk_type == SOCK_STREAM) {
600 val &= ~INET_ECN_MASK;
601 val |= inet->tos & INET_ECN_MASK;
602 }
603 if (inet->tos != val) {
604 inet->tos = val;
605 sk->sk_priority = rt_tos2priority(val);
606 sk_dst_reset(sk);
607 }
608 break;
609 case IP_TTL:
610 if (optlen < 1)
611 goto e_inval;
612 if (val != -1 && (val < 1 || val > 255))
613 goto e_inval;
614 inet->uc_ttl = val;
615 break;
616 case IP_HDRINCL:
617 if (sk->sk_type != SOCK_RAW) {
618 err = -ENOPROTOOPT;
619 break;
620 }
621 inet->hdrincl = val ? 1 : 0;
622 break;
623 case IP_NODEFRAG:
624 if (sk->sk_type != SOCK_RAW) {
625 err = -ENOPROTOOPT;
626 break;
627 }
628 inet->nodefrag = val ? 1 : 0;
629 break;
630 case IP_MTU_DISCOVER:
631 if (val < IP_PMTUDISC_DONT || val > IP_PMTUDISC_OMIT)
632 goto e_inval;
633 inet->pmtudisc = val;
634 break;
635 case IP_RECVERR:
636 inet->recverr = !!val;
637 if (!val)
638 skb_queue_purge(&sk->sk_error_queue);
639 break;
640 case IP_MULTICAST_TTL:
641 if (sk->sk_type == SOCK_STREAM)
642 goto e_inval;
643 if (optlen < 1)
644 goto e_inval;
645 if (val == -1)
646 val = 1;
647 if (val < 0 || val > 255)
648 goto e_inval;
649 inet->mc_ttl = val;
650 break;
651 case IP_MULTICAST_LOOP:
652 if (optlen < 1)
653 goto e_inval;
654 inet->mc_loop = !!val;
655 break;
656 case IP_UNICAST_IF:
657 {
658 struct net_device *dev = NULL;
659 int ifindex;
660
661 if (optlen != sizeof(int))
662 goto e_inval;
663
664 ifindex = (__force int)ntohl((__force __be32)val);
665 if (ifindex == 0) {
666 inet->uc_index = 0;
667 err = 0;
668 break;
669 }
670
671 dev = dev_get_by_index(sock_net(sk), ifindex);
672 err = -EADDRNOTAVAIL;
673 if (!dev)
674 break;
675 dev_put(dev);
676
677 err = -EINVAL;
678 if (sk->sk_bound_dev_if)
679 break;
680
681 inet->uc_index = ifindex;
682 err = 0;
683 break;
684 }
685 case IP_MULTICAST_IF:
686 {
687 struct ip_mreqn mreq;
688 struct net_device *dev = NULL;
689
690 if (sk->sk_type == SOCK_STREAM)
691 goto e_inval;
692 /*
693 * Check the arguments are allowable
694 */
695
696 if (optlen < sizeof(struct in_addr))
697 goto e_inval;
698
699 err = -EFAULT;
700 if (optlen >= sizeof(struct ip_mreqn)) {
701 if (copy_from_user(&mreq, optval, sizeof(mreq)))
702 break;
703 } else {
704 memset(&mreq, 0, sizeof(mreq));
705 if (optlen >= sizeof(struct ip_mreq)) {
706 if (copy_from_user(&mreq, optval,
707 sizeof(struct ip_mreq)))
708 break;
709 } else if (optlen >= sizeof(struct in_addr)) {
710 if (copy_from_user(&mreq.imr_address, optval,
711 sizeof(struct in_addr)))
712 break;
713 }
714 }
715
716 if (!mreq.imr_ifindex) {
717 if (mreq.imr_address.s_addr == htonl(INADDR_ANY)) {
718 inet->mc_index = 0;
719 inet->mc_addr = 0;
720 err = 0;
721 break;
722 }
723 dev = ip_dev_find(sock_net(sk), mreq.imr_address.s_addr);
724 if (dev)
725 mreq.imr_ifindex = dev->ifindex;
726 } else
727 dev = dev_get_by_index(sock_net(sk), mreq.imr_ifindex);
728
729
730 err = -EADDRNOTAVAIL;
731 if (!dev)
732 break;
733 dev_put(dev);
734
735 err = -EINVAL;
736 if (sk->sk_bound_dev_if &&
737 mreq.imr_ifindex != sk->sk_bound_dev_if)
738 break;
739
740 inet->mc_index = mreq.imr_ifindex;
741 inet->mc_addr = mreq.imr_address.s_addr;
742 err = 0;
743 break;
744 }
745
746 case IP_ADD_MEMBERSHIP:
747 case IP_DROP_MEMBERSHIP:
748 {
749 struct ip_mreqn mreq;
750
751 err = -EPROTO;
752 if (inet_sk(sk)->is_icsk)
753 break;
754
755 if (optlen < sizeof(struct ip_mreq))
756 goto e_inval;
757 err = -EFAULT;
758 if (optlen >= sizeof(struct ip_mreqn)) {
759 if (copy_from_user(&mreq, optval, sizeof(mreq)))
760 break;
761 } else {
762 memset(&mreq, 0, sizeof(mreq));
763 if (copy_from_user(&mreq, optval, sizeof(struct ip_mreq)))
764 break;
765 }
766
767 if (optname == IP_ADD_MEMBERSHIP)
768 err = ip_mc_join_group(sk, &mreq);
769 else
770 err = ip_mc_leave_group(sk, &mreq);
771 break;
772 }
773 case IP_MSFILTER:
774 {
775 struct ip_msfilter *msf;
776
777 if (optlen < IP_MSFILTER_SIZE(0))
778 goto e_inval;
779 if (optlen > sysctl_optmem_max) {
780 err = -ENOBUFS;
781 break;
782 }
783 msf = kmalloc(optlen, GFP_KERNEL);
784 if (!msf) {
785 err = -ENOBUFS;
786 break;
787 }
788 err = -EFAULT;
789 if (copy_from_user(msf, optval, optlen)) {
790 kfree(msf);
791 break;
792 }
793 /* numsrc >= (1G-4) overflow in 32 bits */
794 if (msf->imsf_numsrc >= 0x3ffffffcU ||
795 msf->imsf_numsrc > sysctl_igmp_max_msf) {
796 kfree(msf);
797 err = -ENOBUFS;
798 break;
799 }
800 if (IP_MSFILTER_SIZE(msf->imsf_numsrc) > optlen) {
801 kfree(msf);
802 err = -EINVAL;
803 break;
804 }
805 err = ip_mc_msfilter(sk, msf, 0);
806 kfree(msf);
807 break;
808 }
809 case IP_BLOCK_SOURCE:
810 case IP_UNBLOCK_SOURCE:
811 case IP_ADD_SOURCE_MEMBERSHIP:
812 case IP_DROP_SOURCE_MEMBERSHIP:
813 {
814 struct ip_mreq_source mreqs;
815 int omode, add;
816
817 if (optlen != sizeof(struct ip_mreq_source))
818 goto e_inval;
819 if (copy_from_user(&mreqs, optval, sizeof(mreqs))) {
820 err = -EFAULT;
821 break;
822 }
823 if (optname == IP_BLOCK_SOURCE) {
824 omode = MCAST_EXCLUDE;
825 add = 1;
826 } else if (optname == IP_UNBLOCK_SOURCE) {
827 omode = MCAST_EXCLUDE;
828 add = 0;
829 } else if (optname == IP_ADD_SOURCE_MEMBERSHIP) {
830 struct ip_mreqn mreq;
831
832 mreq.imr_multiaddr.s_addr = mreqs.imr_multiaddr;
833 mreq.imr_address.s_addr = mreqs.imr_interface;
834 mreq.imr_ifindex = 0;
835 err = ip_mc_join_group(sk, &mreq);
836 if (err && err != -EADDRINUSE)
837 break;
838 omode = MCAST_INCLUDE;
839 add = 1;
840 } else /* IP_DROP_SOURCE_MEMBERSHIP */ {
841 omode = MCAST_INCLUDE;
842 add = 0;
843 }
844 err = ip_mc_source(add, omode, sk, &mreqs, 0);
845 break;
846 }
847 case MCAST_JOIN_GROUP:
848 case MCAST_LEAVE_GROUP:
849 {
850 struct group_req greq;
851 struct sockaddr_in *psin;
852 struct ip_mreqn mreq;
853
854 if (optlen < sizeof(struct group_req))
855 goto e_inval;
856 err = -EFAULT;
857 if (copy_from_user(&greq, optval, sizeof(greq)))
858 break;
859 psin = (struct sockaddr_in *)&greq.gr_group;
860 if (psin->sin_family != AF_INET)
861 goto e_inval;
862 memset(&mreq, 0, sizeof(mreq));
863 mreq.imr_multiaddr = psin->sin_addr;
864 mreq.imr_ifindex = greq.gr_interface;
865
866 if (optname == MCAST_JOIN_GROUP)
867 err = ip_mc_join_group(sk, &mreq);
868 else
869 err = ip_mc_leave_group(sk, &mreq);
870 break;
871 }
872 case MCAST_JOIN_SOURCE_GROUP:
873 case MCAST_LEAVE_SOURCE_GROUP:
874 case MCAST_BLOCK_SOURCE:
875 case MCAST_UNBLOCK_SOURCE:
876 {
877 struct group_source_req greqs;
878 struct ip_mreq_source mreqs;
879 struct sockaddr_in *psin;
880 int omode, add;
881
882 if (optlen != sizeof(struct group_source_req))
883 goto e_inval;
884 if (copy_from_user(&greqs, optval, sizeof(greqs))) {
885 err = -EFAULT;
886 break;
887 }
888 if (greqs.gsr_group.ss_family != AF_INET ||
889 greqs.gsr_source.ss_family != AF_INET) {
890 err = -EADDRNOTAVAIL;
891 break;
892 }
893 psin = (struct sockaddr_in *)&greqs.gsr_group;
894 mreqs.imr_multiaddr = psin->sin_addr.s_addr;
895 psin = (struct sockaddr_in *)&greqs.gsr_source;
896 mreqs.imr_sourceaddr = psin->sin_addr.s_addr;
897 mreqs.imr_interface = 0; /* use index for mc_source */
898
899 if (optname == MCAST_BLOCK_SOURCE) {
900 omode = MCAST_EXCLUDE;
901 add = 1;
902 } else if (optname == MCAST_UNBLOCK_SOURCE) {
903 omode = MCAST_EXCLUDE;
904 add = 0;
905 } else if (optname == MCAST_JOIN_SOURCE_GROUP) {
906 struct ip_mreqn mreq;
907
908 psin = (struct sockaddr_in *)&greqs.gsr_group;
909 mreq.imr_multiaddr = psin->sin_addr;
910 mreq.imr_address.s_addr = 0;
911 mreq.imr_ifindex = greqs.gsr_interface;
912 err = ip_mc_join_group(sk, &mreq);
913 if (err && err != -EADDRINUSE)
914 break;
915 greqs.gsr_interface = mreq.imr_ifindex;
916 omode = MCAST_INCLUDE;
917 add = 1;
918 } else /* MCAST_LEAVE_SOURCE_GROUP */ {
919 omode = MCAST_INCLUDE;
920 add = 0;
921 }
922 err = ip_mc_source(add, omode, sk, &mreqs,
923 greqs.gsr_interface);
924 break;
925 }
926 case MCAST_MSFILTER:
927 {
928 struct sockaddr_in *psin;
929 struct ip_msfilter *msf = NULL;
930 struct group_filter *gsf = NULL;
931 int msize, i, ifindex;
932
933 if (optlen < GROUP_FILTER_SIZE(0))
934 goto e_inval;
935 if (optlen > sysctl_optmem_max) {
936 err = -ENOBUFS;
937 break;
938 }
939 gsf = kmalloc(optlen, GFP_KERNEL);
940 if (!gsf) {
941 err = -ENOBUFS;
942 break;
943 }
944 err = -EFAULT;
945 if (copy_from_user(gsf, optval, optlen))
946 goto mc_msf_out;
947
948 /* numsrc >= (4G-140)/128 overflow in 32 bits */
949 if (gsf->gf_numsrc >= 0x1ffffff ||
950 gsf->gf_numsrc > sysctl_igmp_max_msf) {
951 err = -ENOBUFS;
952 goto mc_msf_out;
953 }
954 if (GROUP_FILTER_SIZE(gsf->gf_numsrc) > optlen) {
955 err = -EINVAL;
956 goto mc_msf_out;
957 }
958 msize = IP_MSFILTER_SIZE(gsf->gf_numsrc);
959 msf = kmalloc(msize, GFP_KERNEL);
960 if (!msf) {
961 err = -ENOBUFS;
962 goto mc_msf_out;
963 }
964 ifindex = gsf->gf_interface;
965 psin = (struct sockaddr_in *)&gsf->gf_group;
966 if (psin->sin_family != AF_INET) {
967 err = -EADDRNOTAVAIL;
968 goto mc_msf_out;
969 }
970 msf->imsf_multiaddr = psin->sin_addr.s_addr;
971 msf->imsf_interface = 0;
972 msf->imsf_fmode = gsf->gf_fmode;
973 msf->imsf_numsrc = gsf->gf_numsrc;
974 err = -EADDRNOTAVAIL;
975 for (i = 0; i < gsf->gf_numsrc; ++i) {
976 psin = (struct sockaddr_in *)&gsf->gf_slist[i];
977
978 if (psin->sin_family != AF_INET)
979 goto mc_msf_out;
980 msf->imsf_slist[i] = psin->sin_addr.s_addr;
981 }
982 kfree(gsf);
983 gsf = NULL;
984
985 err = ip_mc_msfilter(sk, msf, ifindex);
986 mc_msf_out:
987 kfree(msf);
988 kfree(gsf);
989 break;
990 }
991 case IP_MULTICAST_ALL:
992 if (optlen < 1)
993 goto e_inval;
994 if (val != 0 && val != 1)
995 goto e_inval;
996 inet->mc_all = val;
997 break;
998 case IP_ROUTER_ALERT:
999 err = ip_ra_control(sk, val ? 1 : 0, NULL);
1000 break;
1001
1002 case IP_FREEBIND:
1003 if (optlen < 1)
1004 goto e_inval;
1005 inet->freebind = !!val;
1006 break;
1007
1008 case IP_IPSEC_POLICY:
1009 case IP_XFRM_POLICY:
1010 err = -EPERM;
1011 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1012 break;
1013 err = xfrm_user_policy(sk, optname, optval, optlen);
1014 break;
1015
1016 case IP_TRANSPARENT:
1017 if (!!val && !ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
1018 !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1019 err = -EPERM;
1020 break;
1021 }
1022 if (optlen < 1)
1023 goto e_inval;
1024 inet->transparent = !!val;
1025 break;
1026
1027 case IP_MINTTL:
1028 if (optlen < 1)
1029 goto e_inval;
1030 if (val < 0 || val > 255)
1031 goto e_inval;
1032 inet->min_ttl = val;
1033 break;
1034
1035 default:
1036 err = -ENOPROTOOPT;
1037 break;
1038 }
1039 release_sock(sk);
1040 return err;
1041
1042 e_inval:
1043 release_sock(sk);
1044 return -EINVAL;
1045 }
1046
1047 /**
1048 * ipv4_pktinfo_prepare - transfert some info from rtable to skb
1049 * @sk: socket
1050 * @skb: buffer
1051 *
1052 * To support IP_CMSG_PKTINFO option, we store rt_iif and specific
1053 * destination in skb->cb[] before dst drop.
1054 * This way, receiver doesn't make cache line misses to read rtable.
1055 */
ipv4_pktinfo_prepare(const struct sock * sk,struct sk_buff * skb)1056 void ipv4_pktinfo_prepare(const struct sock *sk, struct sk_buff *skb)
1057 {
1058 struct in_pktinfo *pktinfo = PKTINFO_SKB_CB(skb);
1059 bool prepare = (inet_sk(sk)->cmsg_flags & IP_CMSG_PKTINFO) ||
1060 ipv6_sk_rxinfo(sk);
1061
1062 if (prepare && skb_rtable(skb)) {
1063 pktinfo->ipi_ifindex = inet_iif(skb);
1064 pktinfo->ipi_spec_dst.s_addr = fib_compute_spec_dst(skb);
1065 } else {
1066 pktinfo->ipi_ifindex = 0;
1067 pktinfo->ipi_spec_dst.s_addr = 0;
1068 }
1069 /* We need to keep the dst for __ip_options_echo()
1070 * We could restrict the test to opt.ts_needtime || opt.srr,
1071 * but the following is good enough as IP options are not often used.
1072 */
1073 if (unlikely(IPCB(skb)->opt.optlen))
1074 skb_dst_force(skb);
1075 else
1076 skb_dst_drop(skb);
1077 }
1078
ip_setsockopt(struct sock * sk,int level,int optname,char __user * optval,unsigned int optlen)1079 int ip_setsockopt(struct sock *sk, int level,
1080 int optname, char __user *optval, unsigned int optlen)
1081 {
1082 int err;
1083
1084 if (level != SOL_IP)
1085 return -ENOPROTOOPT;
1086
1087 err = do_ip_setsockopt(sk, level, optname, optval, optlen);
1088 #ifdef CONFIG_NETFILTER
1089 /* we need to exclude all possible ENOPROTOOPTs except default case */
1090 if (err == -ENOPROTOOPT && optname != IP_HDRINCL &&
1091 optname != IP_IPSEC_POLICY &&
1092 optname != IP_XFRM_POLICY &&
1093 !ip_mroute_opt(optname)) {
1094 lock_sock(sk);
1095 err = nf_setsockopt(sk, PF_INET, optname, optval, optlen);
1096 release_sock(sk);
1097 }
1098 #endif
1099 return err;
1100 }
1101 EXPORT_SYMBOL(ip_setsockopt);
1102
1103 #ifdef CONFIG_COMPAT
compat_ip_setsockopt(struct sock * sk,int level,int optname,char __user * optval,unsigned int optlen)1104 int compat_ip_setsockopt(struct sock *sk, int level, int optname,
1105 char __user *optval, unsigned int optlen)
1106 {
1107 int err;
1108
1109 if (level != SOL_IP)
1110 return -ENOPROTOOPT;
1111
1112 if (optname >= MCAST_JOIN_GROUP && optname <= MCAST_MSFILTER)
1113 return compat_mc_setsockopt(sk, level, optname, optval, optlen,
1114 ip_setsockopt);
1115
1116 err = do_ip_setsockopt(sk, level, optname, optval, optlen);
1117 #ifdef CONFIG_NETFILTER
1118 /* we need to exclude all possible ENOPROTOOPTs except default case */
1119 if (err == -ENOPROTOOPT && optname != IP_HDRINCL &&
1120 optname != IP_IPSEC_POLICY &&
1121 optname != IP_XFRM_POLICY &&
1122 !ip_mroute_opt(optname)) {
1123 lock_sock(sk);
1124 err = compat_nf_setsockopt(sk, PF_INET, optname,
1125 optval, optlen);
1126 release_sock(sk);
1127 }
1128 #endif
1129 return err;
1130 }
1131 EXPORT_SYMBOL(compat_ip_setsockopt);
1132 #endif
1133
1134 /*
1135 * Get the options. Note for future reference. The GET of IP options gets
1136 * the _received_ ones. The set sets the _sent_ ones.
1137 */
1138
do_ip_getsockopt(struct sock * sk,int level,int optname,char __user * optval,int __user * optlen,unsigned int flags)1139 static int do_ip_getsockopt(struct sock *sk, int level, int optname,
1140 char __user *optval, int __user *optlen, unsigned int flags)
1141 {
1142 struct inet_sock *inet = inet_sk(sk);
1143 int val;
1144 int len;
1145
1146 if (level != SOL_IP)
1147 return -EOPNOTSUPP;
1148
1149 if (ip_mroute_opt(optname))
1150 return ip_mroute_getsockopt(sk, optname, optval, optlen);
1151
1152 if (get_user(len, optlen))
1153 return -EFAULT;
1154 if (len < 0)
1155 return -EINVAL;
1156
1157 lock_sock(sk);
1158
1159 switch (optname) {
1160 case IP_OPTIONS:
1161 {
1162 unsigned char optbuf[sizeof(struct ip_options)+40];
1163 struct ip_options *opt = (struct ip_options *)optbuf;
1164 struct ip_options_rcu *inet_opt;
1165
1166 inet_opt = rcu_dereference_protected(inet->inet_opt,
1167 sock_owned_by_user(sk));
1168 opt->optlen = 0;
1169 if (inet_opt)
1170 memcpy(optbuf, &inet_opt->opt,
1171 sizeof(struct ip_options) +
1172 inet_opt->opt.optlen);
1173 release_sock(sk);
1174
1175 if (opt->optlen == 0)
1176 return put_user(0, optlen);
1177
1178 ip_options_undo(opt);
1179
1180 len = min_t(unsigned int, len, opt->optlen);
1181 if (put_user(len, optlen))
1182 return -EFAULT;
1183 if (copy_to_user(optval, opt->__data, len))
1184 return -EFAULT;
1185 return 0;
1186 }
1187 case IP_PKTINFO:
1188 val = (inet->cmsg_flags & IP_CMSG_PKTINFO) != 0;
1189 break;
1190 case IP_RECVTTL:
1191 val = (inet->cmsg_flags & IP_CMSG_TTL) != 0;
1192 break;
1193 case IP_RECVTOS:
1194 val = (inet->cmsg_flags & IP_CMSG_TOS) != 0;
1195 break;
1196 case IP_RECVOPTS:
1197 val = (inet->cmsg_flags & IP_CMSG_RECVOPTS) != 0;
1198 break;
1199 case IP_RETOPTS:
1200 val = (inet->cmsg_flags & IP_CMSG_RETOPTS) != 0;
1201 break;
1202 case IP_PASSSEC:
1203 val = (inet->cmsg_flags & IP_CMSG_PASSSEC) != 0;
1204 break;
1205 case IP_RECVORIGDSTADDR:
1206 val = (inet->cmsg_flags & IP_CMSG_ORIGDSTADDR) != 0;
1207 break;
1208 case IP_TOS:
1209 val = inet->tos;
1210 break;
1211 case IP_TTL:
1212 val = (inet->uc_ttl == -1 ?
1213 sysctl_ip_default_ttl :
1214 inet->uc_ttl);
1215 break;
1216 case IP_HDRINCL:
1217 val = inet->hdrincl;
1218 break;
1219 case IP_NODEFRAG:
1220 val = inet->nodefrag;
1221 break;
1222 case IP_MTU_DISCOVER:
1223 val = inet->pmtudisc;
1224 break;
1225 case IP_MTU:
1226 {
1227 struct dst_entry *dst;
1228 val = 0;
1229 dst = sk_dst_get(sk);
1230 if (dst) {
1231 val = dst_mtu(dst);
1232 dst_release(dst);
1233 }
1234 if (!val) {
1235 release_sock(sk);
1236 return -ENOTCONN;
1237 }
1238 break;
1239 }
1240 case IP_RECVERR:
1241 val = inet->recverr;
1242 break;
1243 case IP_MULTICAST_TTL:
1244 val = inet->mc_ttl;
1245 break;
1246 case IP_MULTICAST_LOOP:
1247 val = inet->mc_loop;
1248 break;
1249 case IP_UNICAST_IF:
1250 val = (__force int)htonl((__u32) inet->uc_index);
1251 break;
1252 case IP_MULTICAST_IF:
1253 {
1254 struct in_addr addr;
1255 len = min_t(unsigned int, len, sizeof(struct in_addr));
1256 addr.s_addr = inet->mc_addr;
1257 release_sock(sk);
1258
1259 if (put_user(len, optlen))
1260 return -EFAULT;
1261 if (copy_to_user(optval, &addr, len))
1262 return -EFAULT;
1263 return 0;
1264 }
1265 case IP_MSFILTER:
1266 {
1267 struct ip_msfilter msf;
1268 int err;
1269
1270 if (len < IP_MSFILTER_SIZE(0)) {
1271 release_sock(sk);
1272 return -EINVAL;
1273 }
1274 if (copy_from_user(&msf, optval, IP_MSFILTER_SIZE(0))) {
1275 release_sock(sk);
1276 return -EFAULT;
1277 }
1278 err = ip_mc_msfget(sk, &msf,
1279 (struct ip_msfilter __user *)optval, optlen);
1280 release_sock(sk);
1281 return err;
1282 }
1283 case MCAST_MSFILTER:
1284 {
1285 struct group_filter gsf;
1286 int err;
1287
1288 if (len < GROUP_FILTER_SIZE(0)) {
1289 release_sock(sk);
1290 return -EINVAL;
1291 }
1292 if (copy_from_user(&gsf, optval, GROUP_FILTER_SIZE(0))) {
1293 release_sock(sk);
1294 return -EFAULT;
1295 }
1296 err = ip_mc_gsfget(sk, &gsf,
1297 (struct group_filter __user *)optval,
1298 optlen);
1299 release_sock(sk);
1300 return err;
1301 }
1302 case IP_MULTICAST_ALL:
1303 val = inet->mc_all;
1304 break;
1305 case IP_PKTOPTIONS:
1306 {
1307 struct msghdr msg;
1308
1309 release_sock(sk);
1310
1311 if (sk->sk_type != SOCK_STREAM)
1312 return -ENOPROTOOPT;
1313
1314 msg.msg_control = (__force void *) optval;
1315 msg.msg_controllen = len;
1316 msg.msg_flags = flags;
1317
1318 if (inet->cmsg_flags & IP_CMSG_PKTINFO) {
1319 struct in_pktinfo info;
1320
1321 info.ipi_addr.s_addr = inet->inet_rcv_saddr;
1322 info.ipi_spec_dst.s_addr = inet->inet_rcv_saddr;
1323 info.ipi_ifindex = inet->mc_index;
1324 put_cmsg(&msg, SOL_IP, IP_PKTINFO, sizeof(info), &info);
1325 }
1326 if (inet->cmsg_flags & IP_CMSG_TTL) {
1327 int hlim = inet->mc_ttl;
1328 put_cmsg(&msg, SOL_IP, IP_TTL, sizeof(hlim), &hlim);
1329 }
1330 if (inet->cmsg_flags & IP_CMSG_TOS) {
1331 int tos = inet->rcv_tos;
1332 put_cmsg(&msg, SOL_IP, IP_TOS, sizeof(tos), &tos);
1333 }
1334 len -= msg.msg_controllen;
1335 return put_user(len, optlen);
1336 }
1337 case IP_FREEBIND:
1338 val = inet->freebind;
1339 break;
1340 case IP_TRANSPARENT:
1341 val = inet->transparent;
1342 break;
1343 case IP_MINTTL:
1344 val = inet->min_ttl;
1345 break;
1346 default:
1347 release_sock(sk);
1348 return -ENOPROTOOPT;
1349 }
1350 release_sock(sk);
1351
1352 if (len < sizeof(int) && len > 0 && val >= 0 && val <= 255) {
1353 unsigned char ucval = (unsigned char)val;
1354 len = 1;
1355 if (put_user(len, optlen))
1356 return -EFAULT;
1357 if (copy_to_user(optval, &ucval, 1))
1358 return -EFAULT;
1359 } else {
1360 len = min_t(unsigned int, sizeof(int), len);
1361 if (put_user(len, optlen))
1362 return -EFAULT;
1363 if (copy_to_user(optval, &val, len))
1364 return -EFAULT;
1365 }
1366 return 0;
1367 }
1368
ip_getsockopt(struct sock * sk,int level,int optname,char __user * optval,int __user * optlen)1369 int ip_getsockopt(struct sock *sk, int level,
1370 int optname, char __user *optval, int __user *optlen)
1371 {
1372 int err;
1373
1374 err = do_ip_getsockopt(sk, level, optname, optval, optlen, 0);
1375 #ifdef CONFIG_NETFILTER
1376 /* we need to exclude all possible ENOPROTOOPTs except default case */
1377 if (err == -ENOPROTOOPT && optname != IP_PKTOPTIONS &&
1378 !ip_mroute_opt(optname)) {
1379 int len;
1380
1381 if (get_user(len, optlen))
1382 return -EFAULT;
1383
1384 lock_sock(sk);
1385 err = nf_getsockopt(sk, PF_INET, optname, optval,
1386 &len);
1387 release_sock(sk);
1388 if (err >= 0)
1389 err = put_user(len, optlen);
1390 return err;
1391 }
1392 #endif
1393 return err;
1394 }
1395 EXPORT_SYMBOL(ip_getsockopt);
1396
1397 #ifdef CONFIG_COMPAT
compat_ip_getsockopt(struct sock * sk,int level,int optname,char __user * optval,int __user * optlen)1398 int compat_ip_getsockopt(struct sock *sk, int level, int optname,
1399 char __user *optval, int __user *optlen)
1400 {
1401 int err;
1402
1403 if (optname == MCAST_MSFILTER)
1404 return compat_mc_getsockopt(sk, level, optname, optval, optlen,
1405 ip_getsockopt);
1406
1407 err = do_ip_getsockopt(sk, level, optname, optval, optlen,
1408 MSG_CMSG_COMPAT);
1409
1410 #ifdef CONFIG_NETFILTER
1411 /* we need to exclude all possible ENOPROTOOPTs except default case */
1412 if (err == -ENOPROTOOPT && optname != IP_PKTOPTIONS &&
1413 !ip_mroute_opt(optname)) {
1414 int len;
1415
1416 if (get_user(len, optlen))
1417 return -EFAULT;
1418
1419 lock_sock(sk);
1420 err = compat_nf_getsockopt(sk, PF_INET, optname, optval, &len);
1421 release_sock(sk);
1422 if (err >= 0)
1423 err = put_user(len, optlen);
1424 return err;
1425 }
1426 #endif
1427 return err;
1428 }
1429 EXPORT_SYMBOL(compat_ip_getsockopt);
1430 #endif
1431