1	// SPDX-License-Identifier: GPL-2.0
2	/*
3	* INET An implementation of the TCP/IP protocol suite for the LINUX
4	* operating system. INET is implemented using the BSD Socket
5	* interface as the means of communication with the user level.
6	*
7	* The IP to API glue.
8	*
9	* Authors: see ip.c
10	*
11	* Fixes:
12	* Many : Split from ip.c , see ip.c for history.
13	* Martin Mares : TOS setting fixed.
14	* Alan Cox : Fixed a couple of oopses in Martin's
15	* TOS tweaks.
16	* Mike McLagan : Routing by source
17	*/
18
19	#include <linux/module.h>
20	#include <linux/types.h>
21	#include <linux/mm.h>
22	#include <linux/skbuff.h>
23	#include <linux/ip.h>
24	#include <linux/icmp.h>
25	#include <linux/inetdevice.h>
26	#include <linux/netdevice.h>
27	#include <linux/slab.h>
28	#include <net/sock.h>
29	#include <net/ip.h>
30	#include <net/icmp.h>
31	#include <net/tcp_states.h>
32	#include <linux/udp.h>
33	#include <linux/igmp.h>
34	#include <linux/netfilter.h>
35	#include <linux/route.h>
36	#include <linux/mroute.h>
37	#include <net/inet_ecn.h>
38	#include <net/route.h>
39	#include <net/xfrm.h>
40	#include <net/compat.h>
41	#include <net/checksum.h>
42	#if IS_ENABLED(CONFIG_IPV6)
43	#include <net/transp_v6.h>
44	#endif
45	#include <net/ip_fib.h>
46
47	#include <linux/errqueue.h>
48	#include <linux/uaccess.h>
49
50	/*
51	* SOL_IP control messages.
52	*/
53
54	static void ip_cmsg_recv_pktinfo(struct msghdr *msg, struct sk_buff *skb)
55	{
56	struct in_pktinfo info = *PKTINFO_SKB_CB(skb);
57
58	info.ipi_addr.s_addr = ip_hdr(skb)->daddr;
59
60	put_cmsg(msg, SOL_IP, IP_PKTINFO, len: sizeof(info), data: &info);
61	}
62
63	static void ip_cmsg_recv_ttl(struct msghdr *msg, struct sk_buff *skb)
64	{
65	int ttl = ip_hdr(skb)->ttl;
66	put_cmsg(msg, SOL_IP, IP_TTL, len: sizeof(int), data: &ttl);
67	}
68
69	static void ip_cmsg_recv_tos(struct msghdr *msg, struct sk_buff *skb)
70	{
71	put_cmsg(msg, SOL_IP, IP_TOS, len: 1, data: &ip_hdr(skb)->tos);
72	}
73
74	static void ip_cmsg_recv_opts(struct msghdr *msg, struct sk_buff *skb)
75	{
76	if (IPCB(skb)->opt.optlen == 0)
77	return;
78
79	put_cmsg(msg, SOL_IP, IP_RECVOPTS, IPCB(skb)->opt.optlen,
80	data: ip_hdr(skb) + 1);
81	}
82
83
84	static void ip_cmsg_recv_retopts(struct net *net, struct msghdr *msg,
85	struct sk_buff *skb)
86	{
87	unsigned char optbuf[sizeof(struct ip_options) + 40];
88	struct ip_options *opt = (struct ip_options *)optbuf;
89
90	if (IPCB(skb)->opt.optlen == 0)
91	return;
92
93	if (ip_options_echo(net, dopt: opt, skb)) {
94	msg->msg_flags |= MSG_CTRUNC;
95	return;
96	}
97	ip_options_undo(opt);
98
99	put_cmsg(msg, SOL_IP, IP_RETOPTS, len: opt->optlen, data: opt->__data);
100	}
101
102	static void ip_cmsg_recv_fragsize(struct msghdr *msg, struct sk_buff *skb)
103	{
104	int val;
105
106	if (IPCB(skb)->frag_max_size == 0)
107	return;
108
109	val = IPCB(skb)->frag_max_size;
110	put_cmsg(msg, SOL_IP, IP_RECVFRAGSIZE, len: sizeof(val), data: &val);
111	}
112
113	static void ip_cmsg_recv_checksum(struct msghdr *msg, struct sk_buff *skb,
114	int tlen, int offset)
115	{
116	__wsum csum = skb->csum;
117
118	if (skb->ip_summed != CHECKSUM_COMPLETE)
119	return;
120
121	if (offset != 0) {
122	int tend_off = skb_transport_offset(skb) + tlen;
123	csum = csum_sub(csum, addend: skb_checksum(skb, offset: tend_off, len: offset, csum: 0));
124	}
125
126	put_cmsg(msg, SOL_IP, IP_CHECKSUM, len: sizeof(__wsum), data: &csum);
127	}
128
129	static void ip_cmsg_recv_security(struct msghdr *msg, struct sk_buff *skb)
130	{
131	char *secdata;
132	u32 seclen, secid;
133	int err;
134
135	err = security_socket_getpeersec_dgram(NULL, skb, secid: &secid);
136	if (err)
137	return;
138
139	err = security_secid_to_secctx(secid, secdata: &secdata, seclen: &seclen);
140	if (err)
141	return;
142
143	put_cmsg(msg, SOL_IP, SCM_SECURITY, len: seclen, data: secdata);
144	security_release_secctx(secdata, seclen);
145	}
146
147	static void ip_cmsg_recv_dstaddr(struct msghdr *msg, struct sk_buff *skb)
148	{
149	__be16 _ports[2], *ports;
150	struct sockaddr_in sin;
151
152	/* All current transport protocols have the port numbers in the
153	* first four bytes of the transport header and this function is
154	* written with this assumption in mind.
155	*/
156	ports = skb_header_pointer(skb, offset: skb_transport_offset(skb),
157	len: sizeof(_ports), buffer: &_ports);
158	if (!ports)
159	return;
160
161	sin.sin_family = AF_INET;
162	sin.sin_addr.s_addr = ip_hdr(skb)->daddr;
163	sin.sin_port = ports[1];
164	memset(sin.sin_zero, 0, sizeof(sin.sin_zero));
165
166	put_cmsg(msg, SOL_IP, IP_ORIGDSTADDR, len: sizeof(sin), data: &sin);
167	}
168
169	void ip_cmsg_recv_offset(struct msghdr *msg, struct sock *sk,
170	struct sk_buff *skb, int tlen, int offset)
171	{
172	unsigned long flags = inet_cmsg_flags(inet_sk(sk));
173
174	if (!flags)
175	return;
176
177	/* Ordered by supposed usage frequency */
178	if (flags & IP_CMSG_PKTINFO) {
179	ip_cmsg_recv_pktinfo(msg, skb);
180
181	flags &= ~IP_CMSG_PKTINFO;
182	if (!flags)
183	return;
184	}
185
186	if (flags & IP_CMSG_TTL) {
187	ip_cmsg_recv_ttl(msg, skb);
188
189	flags &= ~IP_CMSG_TTL;
190	if (!flags)
191	return;
192	}
193
194	if (flags & IP_CMSG_TOS) {
195	ip_cmsg_recv_tos(msg, skb);
196
197	flags &= ~IP_CMSG_TOS;
198	if (!flags)
199	return;
200	}
201
202	if (flags & IP_CMSG_RECVOPTS) {
203	ip_cmsg_recv_opts(msg, skb);
204
205	flags &= ~IP_CMSG_RECVOPTS;
206	if (!flags)
207	return;
208	}
209
210	if (flags & IP_CMSG_RETOPTS) {
211	ip_cmsg_recv_retopts(net: 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
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(a: &src_info->ipi6_addr))
262	return -EINVAL;
263	if (src_info->ipi6_ifindex)
264	ipc->oif = src_info->ipi6_ifindex;
265	ipc->addr = src_info->ipi6_addr.s6_addr32[3];
266	continue;
267	}
268	#endif
269	if (cmsg->cmsg_level == SOL_SOCKET) {
270	err = __sock_cmsg_send(sk, cmsg, sockc: &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, optp: &ipc->opt,
284	data: KERNEL_SOCKPTR(CMSG_DATA(cmsg)),
285	optlen: err < 40 ? err : 40);
286	if (err)
287	return err;
288	break;
289	case IP_PKTINFO:
290	{
291	struct in_pktinfo *info;
292	if (cmsg->cmsg_len != CMSG_LEN(sizeof(struct in_pktinfo)))
293	return -EINVAL;
294	info = (struct in_pktinfo *)CMSG_DATA(cmsg);
295	if (info->ipi_ifindex)
296	ipc->oif = info->ipi_ifindex;
297	ipc->addr = info->ipi_spec_dst.s_addr;
298	break;
299	}
300	case IP_TTL:
301	if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
302	return -EINVAL;
303	val = *(int *)CMSG_DATA(cmsg);
304	if (val < 1 || val > 255)
305	return -EINVAL;
306	ipc->ttl = val;
307	break;
308	case IP_TOS:
309	if (cmsg->cmsg_len == CMSG_LEN(sizeof(int)))
310	val = *(int *)CMSG_DATA(cmsg);
311	else if (cmsg->cmsg_len == CMSG_LEN(sizeof(u8)))
312	val = *(u8 *)CMSG_DATA(cmsg);
313	else
314	return -EINVAL;
315	if (val < 0 || val > 255)
316	return -EINVAL;
317	ipc->tos = val;
318	ipc->priority = rt_tos2priority(tos: ipc->tos);
319	break;
320	case IP_PROTOCOL:
321	if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
322	return -EINVAL;
323	val = *(int *)CMSG_DATA(cmsg);
324	if (val < 1 || val > 255)
325	return -EINVAL;
326	ipc->protocol = val;
327	break;
328	default:
329	return -EINVAL;
330	}
331	}
332	return 0;
333	}
334
335	static void ip_ra_destroy_rcu(struct rcu_head *head)
336	{
337	struct ip_ra_chain *ra = container_of(head, struct ip_ra_chain, rcu);
338
339	sock_put(sk: ra->saved_sk);
340	kfree(objp: ra);
341	}
342
343	int ip_ra_control(struct sock *sk, unsigned char on,
344	void (*destructor)(struct sock *))
345	{
346	struct ip_ra_chain *ra, *new_ra;
347	struct ip_ra_chain __rcu **rap;
348	struct net *net = sock_net(sk);
349
350	if (sk->sk_type != SOCK_RAW || inet_sk(sk)->inet_num == IPPROTO_RAW)
351	return -EINVAL;
352
353	new_ra = on ? kmalloc(size: sizeof(*new_ra), GFP_KERNEL) : NULL;
354	if (on && !new_ra)
355	return -ENOMEM;
356
357	mutex_lock(&net->ipv4.ra_mutex);
358	for (rap = &net->ipv4.ra_chain;
359	(ra = rcu_dereference_protected(*rap,
360	lockdep_is_held(&net->ipv4.ra_mutex))) != NULL;
361	rap = &ra->next) {
362	if (ra->sk == sk) {
363	if (on) {
364	mutex_unlock(lock: &net->ipv4.ra_mutex);
365	kfree(objp: new_ra);
366	return -EADDRINUSE;
367	}
368	/* dont let ip_call_ra_chain() use sk again */
369	ra->sk = NULL;
370	RCU_INIT_POINTER(*rap, ra->next);
371	mutex_unlock(lock: &net->ipv4.ra_mutex);
372
373	if (ra->destructor)
374	ra->destructor(sk);
375	/*
376	* Delay sock_put(sk) and kfree(ra) after one rcu grace
377	* period. This guarantee ip_call_ra_chain() dont need
378	* to mess with socket refcounts.
379	*/
380	ra->saved_sk = sk;
381	call_rcu(head: &ra->rcu, func: ip_ra_destroy_rcu);
382	return 0;
383	}
384	}
385	if (!new_ra) {
386	mutex_unlock(lock: &net->ipv4.ra_mutex);
387	return -ENOBUFS;
388	}
389	new_ra->sk = sk;
390	new_ra->destructor = destructor;
391
392	RCU_INIT_POINTER(new_ra->next, ra);
393	rcu_assign_pointer(*rap, new_ra);
394	sock_hold(sk);
395	mutex_unlock(lock: &net->ipv4.ra_mutex);
396
397	return 0;
398	}
399
400	static void ipv4_icmp_error_rfc4884(const struct sk_buff *skb,
401	struct sock_ee_data_rfc4884 *out)
402	{
403	switch (icmp_hdr(skb)->type) {
404	case ICMP_DEST_UNREACH:
405	case ICMP_TIME_EXCEEDED:
406	case ICMP_PARAMETERPROB:
407	ip_icmp_error_rfc4884(skb, out, thlen: sizeof(struct icmphdr),
408	off: icmp_hdr(skb)->un.reserved[1] * 4);
409	}
410	}
411
412	void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
413	__be16 port, u32 info, u8 *payload)
414	{
415	struct sock_exterr_skb *serr;
416
417	skb = skb_clone(skb, GFP_ATOMIC);
418	if (!skb)
419	return;
420
421	serr = SKB_EXT_ERR(skb);
422	serr->ee.ee_errno = err;
423	serr->ee.ee_origin = SO_EE_ORIGIN_ICMP;
424	serr->ee.ee_type = icmp_hdr(skb)->type;
425	serr->ee.ee_code = icmp_hdr(skb)->code;
426	serr->ee.ee_pad = 0;
427	serr->ee.ee_info = info;
428	serr->ee.ee_data = 0;
429	serr->addr_offset = (u8 *)&(((struct iphdr *)(icmp_hdr(skb) + 1))->daddr) -
430	skb_network_header(skb);
431	serr->port = port;
432
433	if (skb_pull(skb, len: payload - skb->data)) {
434	if (inet_test_bit(RECVERR_RFC4884, sk))
435	ipv4_icmp_error_rfc4884(skb, out: &serr->ee.ee_rfc4884);
436
437	skb_reset_transport_header(skb);
438	if (sock_queue_err_skb(sk, skb) == 0)
439	return;
440	}
441	kfree_skb(skb);
442	}
443	EXPORT_SYMBOL_GPL(ip_icmp_error);
444
445	void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 port, u32 info)
446	{
447	struct sock_exterr_skb *serr;
448	struct iphdr *iph;
449	struct sk_buff *skb;
450
451	if (!inet_test_bit(RECVERR, sk))
452	return;
453
454	skb = alloc_skb(size: sizeof(struct iphdr), GFP_ATOMIC);
455	if (!skb)
456	return;
457
458	skb_put(skb, len: sizeof(struct iphdr));
459	skb_reset_network_header(skb);
460	iph = ip_hdr(skb);
461	iph->daddr = daddr;
462
463	serr = SKB_EXT_ERR(skb);
464	serr->ee.ee_errno = err;
465	serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
466	serr->ee.ee_type = 0;
467	serr->ee.ee_code = 0;
468	serr->ee.ee_pad = 0;
469	serr->ee.ee_info = info;
470	serr->ee.ee_data = 0;
471	serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
472	serr->port = port;
473
474	__skb_pull(skb, len: skb_tail_pointer(skb) - skb->data);
475	skb_reset_transport_header(skb);
476
477	if (sock_queue_err_skb(sk, skb))
478	kfree_skb(skb);
479	}
480
481	/* For some errors we have valid addr_offset even with zero payload and
482	* zero port. Also, addr_offset should be supported if port is set.
483	*/
484	static inline bool ipv4_datagram_support_addr(struct sock_exterr_skb *serr)
485	{
486	return serr->ee.ee_origin == SO_EE_ORIGIN_ICMP ||
487	serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL || serr->port;
488	}
489
490	/* IPv4 supports cmsg on all imcp errors and some timestamps
491	*
492	* Timestamp code paths do not initialize the fields expected by cmsg:
493	* the PKTINFO fields in skb->cb[]. Fill those in here.
494	*/
495	static bool ipv4_datagram_support_cmsg(const struct sock *sk,
496	struct sk_buff *skb,
497	int ee_origin)
498	{
499	struct in_pktinfo *info;
500
501	if (ee_origin == SO_EE_ORIGIN_ICMP)
502	return true;
503
504	if (ee_origin == SO_EE_ORIGIN_LOCAL)
505	return false;
506
507	/* Support IP_PKTINFO on tstamp packets if requested, to correlate
508	* timestamp with egress dev. Not possible for packets without iif
509	* or without payload (SOF_TIMESTAMPING_OPT_TSONLY).
510	*/
511	info = PKTINFO_SKB_CB(skb);
512	if (!(READ_ONCE(sk->sk_tsflags) & SOF_TIMESTAMPING_OPT_CMSG) ||
513	!info->ipi_ifindex)
514	return false;
515
516	info->ipi_spec_dst.s_addr = ip_hdr(skb)->saddr;
517	return true;
518	}
519
520	/*
521	* Handle MSG_ERRQUEUE
522	*/
523	int ip_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
524	{
525	struct sock_exterr_skb *serr;
526	struct sk_buff *skb;
527	DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name);
528	struct {
529	struct sock_extended_err ee;
530	struct sockaddr_in offender;
531	} errhdr;
532	int err;
533	int copied;
534
535	err = -EAGAIN;
536	skb = sock_dequeue_err_skb(sk);
537	if (!skb)
538	goto out;
539
540	copied = skb->len;
541	if (copied > len) {
542	msg->msg_flags |= MSG_TRUNC;
543	copied = len;
544	}
545	err = skb_copy_datagram_msg(from: skb, offset: 0, msg, size: copied);
546	if (unlikely(err)) {
547	kfree_skb(skb);
548	return err;
549	}
550	sock_recv_timestamp(msg, sk, skb);
551
552	serr = SKB_EXT_ERR(skb);
553
554	if (sin && ipv4_datagram_support_addr(serr)) {
555	sin->sin_family = AF_INET;
556	sin->sin_addr.s_addr = *(__be32 *)(skb_network_header(skb) +
557	serr->addr_offset);
558	sin->sin_port = serr->port;
559	memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
560	*addr_len = sizeof(*sin);
561	}
562
563	memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
564	sin = &errhdr.offender;
565	memset(sin, 0, sizeof(*sin));
566
567	if (ipv4_datagram_support_cmsg(sk, skb, ee_origin: serr->ee.ee_origin)) {
568	sin->sin_family = AF_INET;
569	sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
570	if (inet_cmsg_flags(inet_sk(sk)))
571	ip_cmsg_recv(msg, skb);
572	}
573
574	put_cmsg(msg, SOL_IP, IP_RECVERR, len: sizeof(errhdr), data: &errhdr);
575
576	/* Now we could try to dump offended packet options */
577
578	msg->msg_flags |= MSG_ERRQUEUE;
579	err = copied;
580
581	consume_skb(skb);
582	out:
583	return err;
584	}
585
586	void __ip_sock_set_tos(struct sock *sk, int val)
587	{
588	u8 old_tos = inet_sk(sk)->tos;
589
590	if (sk->sk_type == SOCK_STREAM) {
591	val &= ~INET_ECN_MASK;
592	val |= old_tos & INET_ECN_MASK;
593	}
594	if (old_tos != val) {
595	WRITE_ONCE(inet_sk(sk)->tos, val);
596	WRITE_ONCE(sk->sk_priority, rt_tos2priority(val));
597	sk_dst_reset(sk);
598	}
599	}
600
601	void ip_sock_set_tos(struct sock *sk, int val)
602	{
603	sockopt_lock_sock(sk);
604	__ip_sock_set_tos(sk, val);
605	sockopt_release_sock(sk);
606	}
607	EXPORT_SYMBOL(ip_sock_set_tos);
608
609	void ip_sock_set_freebind(struct sock *sk)
610	{
611	inet_set_bit(FREEBIND, sk);
612	}
613	EXPORT_SYMBOL(ip_sock_set_freebind);
614
615	void ip_sock_set_recverr(struct sock *sk)
616	{
617	inet_set_bit(RECVERR, sk);
618	}
619	EXPORT_SYMBOL(ip_sock_set_recverr);
620
621	int ip_sock_set_mtu_discover(struct sock *sk, int val)
622	{
623	if (val < IP_PMTUDISC_DONT || val > IP_PMTUDISC_OMIT)
624	return -EINVAL;
625	WRITE_ONCE(inet_sk(sk)->pmtudisc, val);
626	return 0;
627	}
628	EXPORT_SYMBOL(ip_sock_set_mtu_discover);
629
630	void ip_sock_set_pktinfo(struct sock *sk)
631	{
632	inet_set_bit(PKTINFO, sk);
633	}
634	EXPORT_SYMBOL(ip_sock_set_pktinfo);
635
636	/*
637	* Socket option code for IP. This is the end of the line after any
638	* TCP,UDP etc options on an IP socket.
639	*/
640	static bool setsockopt_needs_rtnl(int optname)
641	{
642	switch (optname) {
643	case IP_ADD_MEMBERSHIP:
644	case IP_ADD_SOURCE_MEMBERSHIP:
645	case IP_BLOCK_SOURCE:
646	case IP_DROP_MEMBERSHIP:
647	case IP_DROP_SOURCE_MEMBERSHIP:
648	case IP_MSFILTER:
649	case IP_UNBLOCK_SOURCE:
650	case MCAST_BLOCK_SOURCE:
651	case MCAST_MSFILTER:
652	case MCAST_JOIN_GROUP:
653	case MCAST_JOIN_SOURCE_GROUP:
654	case MCAST_LEAVE_GROUP:
655	case MCAST_LEAVE_SOURCE_GROUP:
656	case MCAST_UNBLOCK_SOURCE:
657	return true;
658	}
659	return false;
660	}
661
662	static int set_mcast_msfilter(struct sock *sk, int ifindex,
663	int numsrc, int fmode,
664	struct sockaddr_storage *group,
665	struct sockaddr_storage *list)
666	{
667	struct ip_msfilter *msf;
668	struct sockaddr_in *psin;
669	int err, i;
670
671	msf = kmalloc(IP_MSFILTER_SIZE(numsrc), GFP_KERNEL);
672	if (!msf)
673	return -ENOBUFS;
674
675	psin = (struct sockaddr_in *)group;
676	if (psin->sin_family != AF_INET)
677	goto Eaddrnotavail;
678	msf->imsf_multiaddr = psin->sin_addr.s_addr;
679	msf->imsf_interface = 0;
680	msf->imsf_fmode = fmode;
681	msf->imsf_numsrc = numsrc;
682	for (i = 0; i < numsrc; ++i) {
683	psin = (struct sockaddr_in *)&list[i];
684
685	if (psin->sin_family != AF_INET)
686	goto Eaddrnotavail;
687	msf->imsf_slist_flex[i] = psin->sin_addr.s_addr;
688	}
689	err = ip_mc_msfilter(sk, msf, ifindex);
690	kfree(objp: msf);
691	return err;
692
693	Eaddrnotavail:
694	kfree(objp: msf);
695	return -EADDRNOTAVAIL;
696	}
697
698	static int copy_group_source_from_sockptr(struct group_source_req *greqs,
699	sockptr_t optval, int optlen)
700	{
701	if (in_compat_syscall()) {
702	struct compat_group_source_req gr32;
703
704	if (optlen != sizeof(gr32))
705	return -EINVAL;
706	if (copy_from_sockptr(dst: &gr32, src: optval, size: sizeof(gr32)))
707	return -EFAULT;
708	greqs->gsr_interface = gr32.gsr_interface;
709	greqs->gsr_group = gr32.gsr_group;
710	greqs->gsr_source = gr32.gsr_source;
711	} else {
712	if (optlen != sizeof(*greqs))
713	return -EINVAL;
714	if (copy_from_sockptr(dst: greqs, src: optval, size: sizeof(*greqs)))
715	return -EFAULT;
716	}
717
718	return 0;
719	}
720
721	static int do_mcast_group_source(struct sock *sk, int optname,
722	sockptr_t optval, int optlen)
723	{
724	struct group_source_req greqs;
725	struct ip_mreq_source mreqs;
726	struct sockaddr_in *psin;
727	int omode, add, err;
728
729	err = copy_group_source_from_sockptr(greqs: &greqs, optval, optlen);
730	if (err)
731	return err;
732
733	if (greqs.gsr_group.ss_family != AF_INET ||
734	greqs.gsr_source.ss_family != AF_INET)
735	return -EADDRNOTAVAIL;
736
737	psin = (struct sockaddr_in *)&greqs.gsr_group;
738	mreqs.imr_multiaddr = psin->sin_addr.s_addr;
739	psin = (struct sockaddr_in *)&greqs.gsr_source;
740	mreqs.imr_sourceaddr = psin->sin_addr.s_addr;
741	mreqs.imr_interface = 0; /* use index for mc_source */
742
743	if (optname == MCAST_BLOCK_SOURCE) {
744	omode = MCAST_EXCLUDE;
745	add = 1;
746	} else if (optname == MCAST_UNBLOCK_SOURCE) {
747	omode = MCAST_EXCLUDE;
748	add = 0;
749	} else if (optname == MCAST_JOIN_SOURCE_GROUP) {
750	struct ip_mreqn mreq;
751
752	psin = (struct sockaddr_in *)&greqs.gsr_group;
753	mreq.imr_multiaddr = psin->sin_addr;
754	mreq.imr_address.s_addr = 0;
755	mreq.imr_ifindex = greqs.gsr_interface;
756	err = ip_mc_join_group_ssm(sk, imr: &mreq, MCAST_INCLUDE);
757	if (err && err != -EADDRINUSE)
758	return err;
759	greqs.gsr_interface = mreq.imr_ifindex;
760	omode = MCAST_INCLUDE;
761	add = 1;
762	} else /* MCAST_LEAVE_SOURCE_GROUP */ {
763	omode = MCAST_INCLUDE;
764	add = 0;
765	}
766	return ip_mc_source(add, omode, sk, mreqs: &mreqs, ifindex: greqs.gsr_interface);
767	}
768
769	static int ip_set_mcast_msfilter(struct sock *sk, sockptr_t optval, int optlen)
770	{
771	struct group_filter *gsf = NULL;
772	int err;
773
774	if (optlen < GROUP_FILTER_SIZE(0))
775	return -EINVAL;
776	if (optlen > READ_ONCE(sock_net(sk)->core.sysctl_optmem_max))
777	return -ENOBUFS;
778
779	gsf = memdup_sockptr(src: optval, len: optlen);
780	if (IS_ERR(ptr: gsf))
781	return PTR_ERR(ptr: gsf);
782
783	/* numsrc >= (4G-140)/128 overflow in 32 bits */
784	err = -ENOBUFS;
785	if (gsf->gf_numsrc >= 0x1ffffff ||
786	gsf->gf_numsrc > READ_ONCE(sock_net(sk)->ipv4.sysctl_igmp_max_msf))
787	goto out_free_gsf;
788
789	err = -EINVAL;
790	if (GROUP_FILTER_SIZE(gsf->gf_numsrc) > optlen)
791	goto out_free_gsf;
792
793	err = set_mcast_msfilter(sk, ifindex: gsf->gf_interface, numsrc: gsf->gf_numsrc,
794	fmode: gsf->gf_fmode, group: &gsf->gf_group,
795	list: gsf->gf_slist_flex);
796	out_free_gsf:
797	kfree(objp: gsf);
798	return err;
799	}
800
801	static int compat_ip_set_mcast_msfilter(struct sock *sk, sockptr_t optval,
802	int optlen)
803	{
804	const int size0 = offsetof(struct compat_group_filter, gf_slist_flex);
805	struct compat_group_filter *gf32;
806	unsigned int n;
807	void *p;
808	int err;
809
810	if (optlen < size0)
811	return -EINVAL;
812	if (optlen > READ_ONCE(sock_net(sk)->core.sysctl_optmem_max) - 4)
813	return -ENOBUFS;
814
815	p = kmalloc(size: optlen + 4, GFP_KERNEL);
816	if (!p)
817	return -ENOMEM;
818	gf32 = p + 4; /* we want ->gf_group and ->gf_slist_flex aligned */
819
820	err = -EFAULT;
821	if (copy_from_sockptr(dst: gf32, src: optval, size: optlen))
822	goto out_free_gsf;
823
824	/* numsrc >= (4G-140)/128 overflow in 32 bits */
825	n = gf32->gf_numsrc;
826	err = -ENOBUFS;
827	if (n >= 0x1ffffff)
828	goto out_free_gsf;
829
830	err = -EINVAL;
831	if (offsetof(struct compat_group_filter, gf_slist_flex[n]) > optlen)
832	goto out_free_gsf;
833
834	/* numsrc >= (4G-140)/128 overflow in 32 bits */
835	err = -ENOBUFS;
836	if (n > READ_ONCE(sock_net(sk)->ipv4.sysctl_igmp_max_msf))
837	goto out_free_gsf;
838	err = set_mcast_msfilter(sk, ifindex: gf32->gf_interface, numsrc: n, fmode: gf32->gf_fmode,
839	group: &gf32->gf_group, list: gf32->gf_slist_flex);
840	out_free_gsf:
841	kfree(objp: p);
842	return err;
843	}
844
845	static int ip_mcast_join_leave(struct sock *sk, int optname,
846	sockptr_t optval, int optlen)
847	{
848	struct ip_mreqn mreq = { };
849	struct sockaddr_in *psin;
850	struct group_req greq;
851
852	if (optlen < sizeof(struct group_req))
853	return -EINVAL;
854	if (copy_from_sockptr(dst: &greq, src: optval, size: sizeof(greq)))
855	return -EFAULT;
856
857	psin = (struct sockaddr_in *)&greq.gr_group;
858	if (psin->sin_family != AF_INET)
859	return -EINVAL;
860	mreq.imr_multiaddr = psin->sin_addr;
861	mreq.imr_ifindex = greq.gr_interface;
862	if (optname == MCAST_JOIN_GROUP)
863	return ip_mc_join_group(sk, imr: &mreq);
864	return ip_mc_leave_group(sk, imr: &mreq);
865	}
866
867	static int compat_ip_mcast_join_leave(struct sock *sk, int optname,
868	sockptr_t optval, int optlen)
869	{
870	struct compat_group_req greq;
871	struct ip_mreqn mreq = { };
872	struct sockaddr_in *psin;
873
874	if (optlen < sizeof(struct compat_group_req))
875	return -EINVAL;
876	if (copy_from_sockptr(dst: &greq, src: optval, size: sizeof(greq)))
877	return -EFAULT;
878
879	psin = (struct sockaddr_in *)&greq.gr_group;
880	if (psin->sin_family != AF_INET)
881	return -EINVAL;
882	mreq.imr_multiaddr = psin->sin_addr;
883	mreq.imr_ifindex = greq.gr_interface;
884
885	if (optname == MCAST_JOIN_GROUP)
886	return ip_mc_join_group(sk, imr: &mreq);
887	return ip_mc_leave_group(sk, imr: &mreq);
888	}
889
890	DEFINE_STATIC_KEY_FALSE(ip4_min_ttl);
891
892	int do_ip_setsockopt(struct sock *sk, int level, int optname,
893	sockptr_t optval, unsigned int optlen)
894	{
895	struct inet_sock *inet = inet_sk(sk);
896	struct net *net = sock_net(sk);
897	int val = 0, err, retv;
898	bool needs_rtnl = setsockopt_needs_rtnl(optname);
899
900	switch (optname) {
901	case IP_PKTINFO:
902	case IP_RECVTTL:
903	case IP_RECVOPTS:
904	case IP_RECVTOS:
905	case IP_RETOPTS:
906	case IP_TOS:
907	case IP_TTL:
908	case IP_HDRINCL:
909	case IP_MTU_DISCOVER:
910	case IP_RECVERR:
911	case IP_ROUTER_ALERT:
912	case IP_FREEBIND:
913	case IP_PASSSEC:
914	case IP_TRANSPARENT:
915	case IP_MINTTL:
916	case IP_NODEFRAG:
917	case IP_BIND_ADDRESS_NO_PORT:
918	case IP_UNICAST_IF:
919	case IP_MULTICAST_TTL:
920	case IP_MULTICAST_ALL:
921	case IP_MULTICAST_LOOP:
922	case IP_RECVORIGDSTADDR:
923	case IP_CHECKSUM:
924	case IP_RECVFRAGSIZE:
925	case IP_RECVERR_RFC4884:
926	case IP_LOCAL_PORT_RANGE:
927	if (optlen >= sizeof(int)) {
928	if (copy_from_sockptr(dst: &val, src: optval, size: sizeof(val)))
929	return -EFAULT;
930	} else if (optlen >= sizeof(char)) {
931	unsigned char ucval;
932
933	if (copy_from_sockptr(dst: &ucval, src: optval, size: sizeof(ucval)))
934	return -EFAULT;
935	val = (int) ucval;
936	}
937	}
938
939	/* If optlen==0, it is equivalent to val == 0 */
940
941	if (optname == IP_ROUTER_ALERT) {
942	retv = ip_ra_control(sk, on: val ? 1 : 0, NULL);
943	if (retv == 0)
944	inet_assign_bit(RTALERT, sk, val);
945	return retv;
946	}
947	if (ip_mroute_opt(opt: optname))
948	return ip_mroute_setsockopt(sk, optname, optval, optlen);
949
950	/* Handle options that can be set without locking the socket. */
951	switch (optname) {
952	case IP_PKTINFO:
953	inet_assign_bit(PKTINFO, sk, val);
954	return 0;
955	case IP_RECVTTL:
956	inet_assign_bit(TTL, sk, val);
957	return 0;
958	case IP_RECVTOS:
959	inet_assign_bit(TOS, sk, val);
960	return 0;
961	case IP_RECVOPTS:
962	inet_assign_bit(RECVOPTS, sk, val);
963	return 0;
964	case IP_RETOPTS:
965	inet_assign_bit(RETOPTS, sk, val);
966	return 0;
967	case IP_PASSSEC:
968	inet_assign_bit(PASSSEC, sk, val);
969	return 0;
970	case IP_RECVORIGDSTADDR:
971	inet_assign_bit(ORIGDSTADDR, sk, val);
972	return 0;
973	case IP_RECVFRAGSIZE:
974	if (sk->sk_type != SOCK_RAW && sk->sk_type != SOCK_DGRAM)
975	return -EINVAL;
976	inet_assign_bit(RECVFRAGSIZE, sk, val);
977	return 0;
978	case IP_RECVERR:
979	inet_assign_bit(RECVERR, sk, val);
980	if (!val)
981	skb_errqueue_purge(list: &sk->sk_error_queue);
982	return 0;
983	case IP_RECVERR_RFC4884:
984	if (val < 0 || val > 1)
985	return -EINVAL;
986	inet_assign_bit(RECVERR_RFC4884, sk, val);
987	return 0;
988	case IP_FREEBIND:
989	if (optlen < 1)
990	return -EINVAL;
991	inet_assign_bit(FREEBIND, sk, val);
992	return 0;
993	case IP_HDRINCL:
994	if (sk->sk_type != SOCK_RAW)
995	return -ENOPROTOOPT;
996	inet_assign_bit(HDRINCL, sk, val);
997	return 0;
998	case IP_MULTICAST_LOOP:
999	if (optlen < 1)
1000	return -EINVAL;
1001	inet_assign_bit(MC_LOOP, sk, val);
1002	return 0;
1003	case IP_MULTICAST_ALL:
1004	if (optlen < 1)
1005	return -EINVAL;
1006	if (val != 0 && val != 1)
1007	return -EINVAL;
1008	inet_assign_bit(MC_ALL, sk, val);
1009	return 0;
1010	case IP_TRANSPARENT:
1011	if (!!val && !sockopt_ns_capable(ns: sock_net(sk)->user_ns, CAP_NET_RAW) &&
1012	!sockopt_ns_capable(ns: sock_net(sk)->user_ns, CAP_NET_ADMIN))
1013	return -EPERM;
1014	if (optlen < 1)
1015	return -EINVAL;
1016	inet_assign_bit(TRANSPARENT, sk, val);
1017	return 0;
1018	case IP_NODEFRAG:
1019	if (sk->sk_type != SOCK_RAW)
1020	return -ENOPROTOOPT;
1021	inet_assign_bit(NODEFRAG, sk, val);
1022	return 0;
1023	case IP_BIND_ADDRESS_NO_PORT:
1024	inet_assign_bit(BIND_ADDRESS_NO_PORT, sk, val);
1025	return 0;
1026	case IP_TTL:
1027	if (optlen < 1)
1028	return -EINVAL;
1029	if (val != -1 && (val < 1 || val > 255))
1030	return -EINVAL;
1031	WRITE_ONCE(inet->uc_ttl, val);
1032	return 0;
1033	case IP_MINTTL:
1034	if (optlen < 1)
1035	return -EINVAL;
1036	if (val < 0 || val > 255)
1037	return -EINVAL;
1038
1039	if (val)
1040	static_branch_enable(&ip4_min_ttl);
1041
1042	WRITE_ONCE(inet->min_ttl, val);
1043	return 0;
1044	case IP_MULTICAST_TTL:
1045	if (sk->sk_type == SOCK_STREAM)
1046	return -EINVAL;
1047	if (optlen < 1)
1048	return -EINVAL;
1049	if (val == -1)
1050	val = 1;
1051	if (val < 0 || val > 255)
1052	return -EINVAL;
1053	WRITE_ONCE(inet->mc_ttl, val);
1054	return 0;
1055	case IP_MTU_DISCOVER:
1056	return ip_sock_set_mtu_discover(sk, val);
1057	case IP_TOS: /* This sets both TOS and Precedence */
1058	ip_sock_set_tos(sk, val);
1059	return 0;
1060	case IP_LOCAL_PORT_RANGE:
1061	{
1062	u16 lo = val;
1063	u16 hi = val >> 16;
1064
1065	if (optlen != sizeof(u32))
1066	return -EINVAL;
1067	if (lo != 0 && hi != 0 && lo > hi)
1068	return -EINVAL;
1069
1070	WRITE_ONCE(inet->local_port_range, val);
1071	return 0;
1072	}
1073	}
1074
1075	err = 0;
1076	if (needs_rtnl)
1077	rtnl_lock();
1078	sockopt_lock_sock(sk);
1079
1080	switch (optname) {
1081	case IP_OPTIONS:
1082	{
1083	struct ip_options_rcu *old, *opt = NULL;
1084
1085	if (optlen > 40)
1086	goto e_inval;
1087	err = ip_options_get(net: sock_net(sk), optp: &opt, data: optval, optlen);
1088	if (err)
1089	break;
1090	old = rcu_dereference_protected(inet->inet_opt,
1091	lockdep_sock_is_held(sk));
1092	if (inet_test_bit(IS_ICSK, sk)) {
1093	struct inet_connection_sock *icsk = inet_csk(sk);
1094	#if IS_ENABLED(CONFIG_IPV6)
1095	if (sk->sk_family == PF_INET ||
1096	(!((1 << sk->sk_state) &
1097	(TCPF_LISTEN | TCPF_CLOSE)) &&
1098	inet->inet_daddr != LOOPBACK4_IPV6)) {
1099	#endif
1100	if (old)
1101	icsk->icsk_ext_hdr_len -= old->opt.optlen;
1102	if (opt)
1103	icsk->icsk_ext_hdr_len += opt->opt.optlen;
1104	icsk->icsk_sync_mss(sk, icsk->icsk_pmtu_cookie);
1105	#if IS_ENABLED(CONFIG_IPV6)
1106	}
1107	#endif
1108	}
1109	rcu_assign_pointer(inet->inet_opt, opt);
1110	if (old)
1111	kfree_rcu(old, rcu);
1112	break;
1113	}
1114	case IP_CHECKSUM:
1115	if (val) {
1116	if (!(inet_test_bit(CHECKSUM, sk))) {
1117	inet_inc_convert_csum(sk);
1118	inet_set_bit(CHECKSUM, sk);
1119	}
1120	} else {
1121	if (inet_test_bit(CHECKSUM, sk)) {
1122	inet_dec_convert_csum(sk);
1123	inet_clear_bit(CHECKSUM, sk);
1124	}
1125	}
1126	break;
1127	case IP_UNICAST_IF:
1128	{
1129	struct net_device *dev = NULL;
1130	int ifindex;
1131	int midx;
1132
1133	if (optlen != sizeof(int))
1134	goto e_inval;
1135
1136	ifindex = (__force int)ntohl((__force __be32)val);
1137	if (ifindex == 0) {
1138	WRITE_ONCE(inet->uc_index, 0);
1139	err = 0;
1140	break;
1141	}
1142
1143	dev = dev_get_by_index(net: sock_net(sk), ifindex);
1144	err = -EADDRNOTAVAIL;
1145	if (!dev)
1146	break;
1147
1148	midx = l3mdev_master_ifindex(dev);
1149	dev_put(dev);
1150
1151	err = -EINVAL;
1152	if (sk->sk_bound_dev_if && midx != sk->sk_bound_dev_if)
1153	break;
1154
1155	WRITE_ONCE(inet->uc_index, ifindex);
1156	err = 0;
1157	break;
1158	}
1159	case IP_MULTICAST_IF:
1160	{
1161	struct ip_mreqn mreq;
1162	struct net_device *dev = NULL;
1163	int midx;
1164
1165	if (sk->sk_type == SOCK_STREAM)
1166	goto e_inval;
1167	/*
1168	* Check the arguments are allowable
1169	*/
1170
1171	if (optlen < sizeof(struct in_addr))
1172	goto e_inval;
1173
1174	err = -EFAULT;
1175	if (optlen >= sizeof(struct ip_mreqn)) {
1176	if (copy_from_sockptr(dst: &mreq, src: optval, size: sizeof(mreq)))
1177	break;
1178	} else {
1179	memset(&mreq, 0, sizeof(mreq));
1180	if (optlen >= sizeof(struct ip_mreq)) {
1181	if (copy_from_sockptr(dst: &mreq, src: optval,
1182	size: sizeof(struct ip_mreq)))
1183	break;
1184	} else if (optlen >= sizeof(struct in_addr)) {
1185	if (copy_from_sockptr(dst: &mreq.imr_address, src: optval,
1186	size: sizeof(struct in_addr)))
1187	break;
1188	}
1189	}
1190
1191	if (!mreq.imr_ifindex) {
1192	if (mreq.imr_address.s_addr == htonl(INADDR_ANY)) {
1193	WRITE_ONCE(inet->mc_index, 0);
1194	WRITE_ONCE(inet->mc_addr, 0);
1195	err = 0;
1196	break;
1197	}
1198	dev = ip_dev_find(net: sock_net(sk), addr: mreq.imr_address.s_addr);
1199	if (dev)
1200	mreq.imr_ifindex = dev->ifindex;
1201	} else
1202	dev = dev_get_by_index(net: sock_net(sk), ifindex: mreq.imr_ifindex);
1203
1204
1205	err = -EADDRNOTAVAIL;
1206	if (!dev)
1207	break;
1208
1209	midx = l3mdev_master_ifindex(dev);
1210
1211	dev_put(dev);
1212
1213	err = -EINVAL;
1214	if (sk->sk_bound_dev_if &&
1215	mreq.imr_ifindex != sk->sk_bound_dev_if &&
1216	midx != sk->sk_bound_dev_if)
1217	break;
1218
1219	WRITE_ONCE(inet->mc_index, mreq.imr_ifindex);
1220	WRITE_ONCE(inet->mc_addr, mreq.imr_address.s_addr);
1221	err = 0;
1222	break;
1223	}
1224
1225	case IP_ADD_MEMBERSHIP:
1226	case IP_DROP_MEMBERSHIP:
1227	{
1228	struct ip_mreqn mreq;
1229
1230	err = -EPROTO;
1231	if (inet_test_bit(IS_ICSK, sk))
1232	break;
1233
1234	if (optlen < sizeof(struct ip_mreq))
1235	goto e_inval;
1236	err = -EFAULT;
1237	if (optlen >= sizeof(struct ip_mreqn)) {
1238	if (copy_from_sockptr(dst: &mreq, src: optval, size: sizeof(mreq)))
1239	break;
1240	} else {
1241	memset(&mreq, 0, sizeof(mreq));
1242	if (copy_from_sockptr(dst: &mreq, src: optval,
1243	size: sizeof(struct ip_mreq)))
1244	break;
1245	}
1246
1247	if (optname == IP_ADD_MEMBERSHIP)
1248	err = ip_mc_join_group(sk, imr: &mreq);
1249	else
1250	err = ip_mc_leave_group(sk, imr: &mreq);
1251	break;
1252	}
1253	case IP_MSFILTER:
1254	{
1255	struct ip_msfilter *msf;
1256
1257	if (optlen < IP_MSFILTER_SIZE(0))
1258	goto e_inval;
1259	if (optlen > READ_ONCE(net->core.sysctl_optmem_max)) {
1260	err = -ENOBUFS;
1261	break;
1262	}
1263	msf = memdup_sockptr(src: optval, len: optlen);
1264	if (IS_ERR(ptr: msf)) {
1265	err = PTR_ERR(ptr: msf);
1266	break;
1267	}
1268	/* numsrc >= (1G-4) overflow in 32 bits */
1269	if (msf->imsf_numsrc >= 0x3ffffffcU ||
1270	msf->imsf_numsrc > READ_ONCE(net->ipv4.sysctl_igmp_max_msf)) {
1271	kfree(objp: msf);
1272	err = -ENOBUFS;
1273	break;
1274	}
1275	if (IP_MSFILTER_SIZE(msf->imsf_numsrc) > optlen) {
1276	kfree(objp: msf);
1277	err = -EINVAL;
1278	break;
1279	}
1280	err = ip_mc_msfilter(sk, msf, ifindex: 0);
1281	kfree(objp: msf);
1282	break;
1283	}
1284	case IP_BLOCK_SOURCE:
1285	case IP_UNBLOCK_SOURCE:
1286	case IP_ADD_SOURCE_MEMBERSHIP:
1287	case IP_DROP_SOURCE_MEMBERSHIP:
1288	{
1289	struct ip_mreq_source mreqs;
1290	int omode, add;
1291
1292	if (optlen != sizeof(struct ip_mreq_source))
1293	goto e_inval;
1294	if (copy_from_sockptr(dst: &mreqs, src: optval, size: sizeof(mreqs))) {
1295	err = -EFAULT;
1296	break;
1297	}
1298	if (optname == IP_BLOCK_SOURCE) {
1299	omode = MCAST_EXCLUDE;
1300	add = 1;
1301	} else if (optname == IP_UNBLOCK_SOURCE) {
1302	omode = MCAST_EXCLUDE;
1303	add = 0;
1304	} else if (optname == IP_ADD_SOURCE_MEMBERSHIP) {
1305	struct ip_mreqn mreq;
1306
1307	mreq.imr_multiaddr.s_addr = mreqs.imr_multiaddr;
1308	mreq.imr_address.s_addr = mreqs.imr_interface;
1309	mreq.imr_ifindex = 0;
1310	err = ip_mc_join_group_ssm(sk, imr: &mreq, MCAST_INCLUDE);
1311	if (err && err != -EADDRINUSE)
1312	break;
1313	omode = MCAST_INCLUDE;
1314	add = 1;
1315	} else /* IP_DROP_SOURCE_MEMBERSHIP */ {
1316	omode = MCAST_INCLUDE;
1317	add = 0;
1318	}
1319	err = ip_mc_source(add, omode, sk, mreqs: &mreqs, ifindex: 0);
1320	break;
1321	}
1322	case MCAST_JOIN_GROUP:
1323	case MCAST_LEAVE_GROUP:
1324	if (in_compat_syscall())
1325	err = compat_ip_mcast_join_leave(sk, optname, optval,
1326	optlen);
1327	else
1328	err = ip_mcast_join_leave(sk, optname, optval, optlen);
1329	break;
1330	case MCAST_JOIN_SOURCE_GROUP:
1331	case MCAST_LEAVE_SOURCE_GROUP:
1332	case MCAST_BLOCK_SOURCE:
1333	case MCAST_UNBLOCK_SOURCE:
1334	err = do_mcast_group_source(sk, optname, optval, optlen);
1335	break;
1336	case MCAST_MSFILTER:
1337	if (in_compat_syscall())
1338	err = compat_ip_set_mcast_msfilter(sk, optval, optlen);
1339	else
1340	err = ip_set_mcast_msfilter(sk, optval, optlen);
1341	break;
1342	case IP_IPSEC_POLICY:
1343	case IP_XFRM_POLICY:
1344	err = -EPERM;
1345	if (!sockopt_ns_capable(ns: sock_net(sk)->user_ns, CAP_NET_ADMIN))
1346	break;
1347	err = xfrm_user_policy(sk, optname, optval, optlen);
1348	break;
1349
1350	default:
1351	err = -ENOPROTOOPT;
1352	break;
1353	}
1354	sockopt_release_sock(sk);
1355	if (needs_rtnl)
1356	rtnl_unlock();
1357	return err;
1358
1359	e_inval:
1360	sockopt_release_sock(sk);
1361	if (needs_rtnl)
1362	rtnl_unlock();
1363	return -EINVAL;
1364	}
1365
1366	/**
1367	* ipv4_pktinfo_prepare - transfer some info from rtable to skb
1368	* @sk: socket
1369	* @skb: buffer
1370	* @drop_dst: if true, drops skb dst
1371	*
1372	* To support IP_CMSG_PKTINFO option, we store rt_iif and specific
1373	* destination in skb->cb[] before dst drop.
1374	* This way, receiver doesn't make cache line misses to read rtable.
1375	*/
1376	void ipv4_pktinfo_prepare(const struct sock *sk, struct sk_buff *skb, bool drop_dst)
1377	{
1378	struct in_pktinfo *pktinfo = PKTINFO_SKB_CB(skb);
1379	bool prepare = inet_test_bit(PKTINFO, sk) ||
1380	ipv6_sk_rxinfo(sk);
1381
1382	if (prepare && skb_rtable(skb)) {
1383	/* skb->cb is overloaded: prior to this point it is IP{6}CB
1384	* which has interface index (iif) as the first member of the
1385	* underlying inet{6}_skb_parm struct. This code then overlays
1386	* PKTINFO_SKB_CB and in_pktinfo also has iif as the first
1387	* element so the iif is picked up from the prior IPCB. If iif
1388	* is the loopback interface, then return the sending interface
1389	* (e.g., process binds socket to eth0 for Tx which is
1390	* redirected to loopback in the rtable/dst).
1391	*/
1392	struct rtable *rt = skb_rtable(skb);
1393	bool l3slave = ipv4_l3mdev_skb(IPCB(skb)->flags);
1394
1395	if (pktinfo->ipi_ifindex == LOOPBACK_IFINDEX)
1396	pktinfo->ipi_ifindex = inet_iif(skb);
1397	else if (l3slave && rt && rt->rt_iif)
1398	pktinfo->ipi_ifindex = rt->rt_iif;
1399
1400	pktinfo->ipi_spec_dst.s_addr = fib_compute_spec_dst(skb);
1401	} else {
1402	pktinfo->ipi_ifindex = 0;
1403	pktinfo->ipi_spec_dst.s_addr = 0;
1404	}
1405	if (drop_dst)
1406	skb_dst_drop(skb);
1407	}
1408
1409	int ip_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
1410	unsigned int optlen)
1411	{
1412	int err;
1413
1414	if (level != SOL_IP)
1415	return -ENOPROTOOPT;
1416
1417	err = do_ip_setsockopt(sk, level, optname, optval, optlen);
1418	#ifdef CONFIG_NETFILTER
1419	/* we need to exclude all possible ENOPROTOOPTs except default case */
1420	if (err == -ENOPROTOOPT && optname != IP_HDRINCL &&
1421	optname != IP_IPSEC_POLICY &&
1422	optname != IP_XFRM_POLICY &&
1423	!ip_mroute_opt(opt: optname))
1424	err = nf_setsockopt(sk, PF_INET, optval: optname, opt: optval, len: optlen);
1425	#endif
1426	return err;
1427	}
1428	EXPORT_SYMBOL(ip_setsockopt);
1429
1430	/*
1431	* Get the options. Note for future reference. The GET of IP options gets
1432	* the _received_ ones. The set sets the _sent_ ones.
1433	*/
1434
1435	static bool getsockopt_needs_rtnl(int optname)
1436	{
1437	switch (optname) {
1438	case IP_MSFILTER:
1439	case MCAST_MSFILTER:
1440	return true;
1441	}
1442	return false;
1443	}
1444
1445	static int ip_get_mcast_msfilter(struct sock *sk, sockptr_t optval,
1446	sockptr_t optlen, int len)
1447	{
1448	const int size0 = offsetof(struct group_filter, gf_slist_flex);
1449	struct group_filter gsf;
1450	int num, gsf_size;
1451	int err;
1452
1453	if (len < size0)
1454	return -EINVAL;
1455	if (copy_from_sockptr(dst: &gsf, src: optval, size: size0))
1456	return -EFAULT;
1457
1458	num = gsf.gf_numsrc;
1459	err = ip_mc_gsfget(sk, gsf: &gsf, optval,
1460	offsetof(struct group_filter, gf_slist_flex));
1461	if (err)
1462	return err;
1463	if (gsf.gf_numsrc < num)
1464	num = gsf.gf_numsrc;
1465	gsf_size = GROUP_FILTER_SIZE(num);
1466	if (copy_to_sockptr(dst: optlen, src: &gsf_size, size: sizeof(int)) ||
1467	copy_to_sockptr(dst: optval, src: &gsf, size: size0))
1468	return -EFAULT;
1469	return 0;
1470	}
1471
1472	static int compat_ip_get_mcast_msfilter(struct sock *sk, sockptr_t optval,
1473	sockptr_t optlen, int len)
1474	{
1475	const int size0 = offsetof(struct compat_group_filter, gf_slist_flex);
1476	struct compat_group_filter gf32;
1477	struct group_filter gf;
1478	int num;
1479	int err;
1480
1481	if (len < size0)
1482	return -EINVAL;
1483	if (copy_from_sockptr(dst: &gf32, src: optval, size: size0))
1484	return -EFAULT;
1485
1486	gf.gf_interface = gf32.gf_interface;
1487	gf.gf_fmode = gf32.gf_fmode;
1488	num = gf.gf_numsrc = gf32.gf_numsrc;
1489	gf.gf_group = gf32.gf_group;
1490
1491	err = ip_mc_gsfget(sk, gsf: &gf, optval,
1492	offsetof(struct compat_group_filter, gf_slist_flex));
1493	if (err)
1494	return err;
1495	if (gf.gf_numsrc < num)
1496	num = gf.gf_numsrc;
1497	len = GROUP_FILTER_SIZE(num) - (sizeof(gf) - sizeof(gf32));
1498	if (copy_to_sockptr(dst: optlen, src: &len, size: sizeof(int)) ||
1499	copy_to_sockptr_offset(dst: optval, offsetof(struct compat_group_filter, gf_fmode),
1500	src: &gf.gf_fmode, size: sizeof(gf.gf_fmode)) ||
1501	copy_to_sockptr_offset(dst: optval, offsetof(struct compat_group_filter, gf_numsrc),
1502	src: &gf.gf_numsrc, size: sizeof(gf.gf_numsrc)))
1503	return -EFAULT;
1504	return 0;
1505	}
1506
1507	int do_ip_getsockopt(struct sock *sk, int level, int optname,
1508	sockptr_t optval, sockptr_t optlen)
1509	{
1510	struct inet_sock *inet = inet_sk(sk);
1511	bool needs_rtnl = getsockopt_needs_rtnl(optname);
1512	int val, err = 0;
1513	int len;
1514
1515	if (level != SOL_IP)
1516	return -EOPNOTSUPP;
1517
1518	if (ip_mroute_opt(opt: optname))
1519	return ip_mroute_getsockopt(sk, optname, optval, optlen);
1520
1521	if (copy_from_sockptr(dst: &len, src: optlen, size: sizeof(int)))
1522	return -EFAULT;
1523	if (len < 0)
1524	return -EINVAL;
1525
1526	/* Handle options that can be read without locking the socket. */
1527	switch (optname) {
1528	case IP_PKTINFO:
1529	val = inet_test_bit(PKTINFO, sk);
1530	goto copyval;
1531	case IP_RECVTTL:
1532	val = inet_test_bit(TTL, sk);
1533	goto copyval;
1534	case IP_RECVTOS:
1535	val = inet_test_bit(TOS, sk);
1536	goto copyval;
1537	case IP_RECVOPTS:
1538	val = inet_test_bit(RECVOPTS, sk);
1539	goto copyval;
1540	case IP_RETOPTS:
1541	val = inet_test_bit(RETOPTS, sk);
1542	goto copyval;
1543	case IP_PASSSEC:
1544	val = inet_test_bit(PASSSEC, sk);
1545	goto copyval;
1546	case IP_RECVORIGDSTADDR:
1547	val = inet_test_bit(ORIGDSTADDR, sk);
1548	goto copyval;
1549	case IP_CHECKSUM:
1550	val = inet_test_bit(CHECKSUM, sk);
1551	goto copyval;
1552	case IP_RECVFRAGSIZE:
1553	val = inet_test_bit(RECVFRAGSIZE, sk);
1554	goto copyval;
1555	case IP_RECVERR:
1556	val = inet_test_bit(RECVERR, sk);
1557	goto copyval;
1558	case IP_RECVERR_RFC4884:
1559	val = inet_test_bit(RECVERR_RFC4884, sk);
1560	goto copyval;
1561	case IP_FREEBIND:
1562	val = inet_test_bit(FREEBIND, sk);
1563	goto copyval;
1564	case IP_HDRINCL:
1565	val = inet_test_bit(HDRINCL, sk);
1566	goto copyval;
1567	case IP_MULTICAST_LOOP:
1568	val = inet_test_bit(MC_LOOP, sk);
1569	goto copyval;
1570	case IP_MULTICAST_ALL:
1571	val = inet_test_bit(MC_ALL, sk);
1572	goto copyval;
1573	case IP_TRANSPARENT:
1574	val = inet_test_bit(TRANSPARENT, sk);
1575	goto copyval;
1576	case IP_NODEFRAG:
1577	val = inet_test_bit(NODEFRAG, sk);
1578	goto copyval;
1579	case IP_BIND_ADDRESS_NO_PORT:
1580	val = inet_test_bit(BIND_ADDRESS_NO_PORT, sk);
1581	goto copyval;
1582	case IP_ROUTER_ALERT:
1583	val = inet_test_bit(RTALERT, sk);
1584	goto copyval;
1585	case IP_TTL:
1586	val = READ_ONCE(inet->uc_ttl);
1587	if (val < 0)
1588	val = READ_ONCE(sock_net(sk)->ipv4.sysctl_ip_default_ttl);
1589	goto copyval;
1590	case IP_MINTTL:
1591	val = READ_ONCE(inet->min_ttl);
1592	goto copyval;
1593	case IP_MULTICAST_TTL:
1594	val = READ_ONCE(inet->mc_ttl);
1595	goto copyval;
1596	case IP_MTU_DISCOVER:
1597	val = READ_ONCE(inet->pmtudisc);
1598	goto copyval;
1599	case IP_TOS:
1600	val = READ_ONCE(inet->tos);
1601	goto copyval;
1602	case IP_OPTIONS:
1603	{
1604	unsigned char optbuf[sizeof(struct ip_options)+40];
1605	struct ip_options *opt = (struct ip_options *)optbuf;
1606	struct ip_options_rcu *inet_opt;
1607
1608	rcu_read_lock();
1609	inet_opt = rcu_dereference(inet->inet_opt);
1610	opt->optlen = 0;
1611	if (inet_opt)
1612	memcpy(optbuf, &inet_opt->opt,
1613	sizeof(struct ip_options) +
1614	inet_opt->opt.optlen);
1615	rcu_read_unlock();
1616
1617	if (opt->optlen == 0) {
1618	len = 0;
1619	return copy_to_sockptr(dst: optlen, src: &len, size: sizeof(int));
1620	}
1621
1622	ip_options_undo(opt);
1623
1624	len = min_t(unsigned int, len, opt->optlen);
1625	if (copy_to_sockptr(dst: optlen, src: &len, size: sizeof(int)))
1626	return -EFAULT;
1627	if (copy_to_sockptr(dst: optval, src: opt->__data, size: len))
1628	return -EFAULT;
1629	return 0;
1630	}
1631	case IP_MTU:
1632	{
1633	struct dst_entry *dst;
1634	val = 0;
1635	dst = sk_dst_get(sk);
1636	if (dst) {
1637	val = dst_mtu(dst);
1638	dst_release(dst);
1639	}
1640	if (!val)
1641	return -ENOTCONN;
1642	goto copyval;
1643	}
1644	case IP_PKTOPTIONS:
1645	{
1646	struct msghdr msg;
1647
1648	if (sk->sk_type != SOCK_STREAM)
1649	return -ENOPROTOOPT;
1650
1651	if (optval.is_kernel) {
1652	msg.msg_control_is_user = false;
1653	msg.msg_control = optval.kernel;
1654	} else {
1655	msg.msg_control_is_user = true;
1656	msg.msg_control_user = optval.user;
1657	}
1658	msg.msg_controllen = len;
1659	msg.msg_flags = in_compat_syscall() ? MSG_CMSG_COMPAT : 0;
1660
1661	if (inet_test_bit(PKTINFO, sk)) {
1662	struct in_pktinfo info;
1663
1664	info.ipi_addr.s_addr = READ_ONCE(inet->inet_rcv_saddr);
1665	info.ipi_spec_dst.s_addr = READ_ONCE(inet->inet_rcv_saddr);
1666	info.ipi_ifindex = READ_ONCE(inet->mc_index);
1667	put_cmsg(&msg, SOL_IP, IP_PKTINFO, len: sizeof(info), data: &info);
1668	}
1669	if (inet_test_bit(TTL, sk)) {
1670	int hlim = READ_ONCE(inet->mc_ttl);
1671
1672	put_cmsg(&msg, SOL_IP, IP_TTL, len: sizeof(hlim), data: &hlim);
1673	}
1674	if (inet_test_bit(TOS, sk)) {
1675	int tos = READ_ONCE(inet->rcv_tos);
1676	put_cmsg(&msg, SOL_IP, IP_TOS, len: sizeof(tos), data: &tos);
1677	}
1678	len -= msg.msg_controllen;
1679	return copy_to_sockptr(dst: optlen, src: &len, size: sizeof(int));
1680	}
1681	case IP_UNICAST_IF:
1682	val = (__force int)htonl((__u32) READ_ONCE(inet->uc_index));
1683	goto copyval;
1684	case IP_MULTICAST_IF:
1685	{
1686	struct in_addr addr;
1687	len = min_t(unsigned int, len, sizeof(struct in_addr));
1688	addr.s_addr = READ_ONCE(inet->mc_addr);
1689
1690	if (copy_to_sockptr(dst: optlen, src: &len, size: sizeof(int)))
1691	return -EFAULT;
1692	if (copy_to_sockptr(dst: optval, src: &addr, size: len))
1693	return -EFAULT;
1694	return 0;
1695	}
1696	case IP_LOCAL_PORT_RANGE:
1697	val = READ_ONCE(inet->local_port_range);
1698	goto copyval;
1699	}
1700
1701	if (needs_rtnl)
1702	rtnl_lock();
1703	sockopt_lock_sock(sk);
1704
1705	switch (optname) {
1706	case IP_MSFILTER:
1707	{
1708	struct ip_msfilter msf;
1709
1710	if (len < IP_MSFILTER_SIZE(0)) {
1711	err = -EINVAL;
1712	goto out;
1713	}
1714	if (copy_from_sockptr(dst: &msf, src: optval, IP_MSFILTER_SIZE(0))) {
1715	err = -EFAULT;
1716	goto out;
1717	}
1718	err = ip_mc_msfget(sk, msf: &msf, optval, optlen);
1719	goto out;
1720	}
1721	case MCAST_MSFILTER:
1722	if (in_compat_syscall())
1723	err = compat_ip_get_mcast_msfilter(sk, optval, optlen,
1724	len);
1725	else
1726	err = ip_get_mcast_msfilter(sk, optval, optlen, len);
1727	goto out;
1728	case IP_PROTOCOL:
1729	val = inet_sk(sk)->inet_num;
1730	break;
1731	default:
1732	sockopt_release_sock(sk);
1733	return -ENOPROTOOPT;
1734	}
1735	sockopt_release_sock(sk);
1736	copyval:
1737	if (len < sizeof(int) && len > 0 && val >= 0 && val <= 255) {
1738	unsigned char ucval = (unsigned char)val;
1739	len = 1;
1740	if (copy_to_sockptr(dst: optlen, src: &len, size: sizeof(int)))
1741	return -EFAULT;
1742	if (copy_to_sockptr(dst: optval, src: &ucval, size: 1))
1743	return -EFAULT;
1744	} else {
1745	len = min_t(unsigned int, sizeof(int), len);
1746	if (copy_to_sockptr(dst: optlen, src: &len, size: sizeof(int)))
1747	return -EFAULT;
1748	if (copy_to_sockptr(dst: optval, src: &val, size: len))
1749	return -EFAULT;
1750	}
1751	return 0;
1752
1753	out:
1754	sockopt_release_sock(sk);
1755	if (needs_rtnl)
1756	rtnl_unlock();
1757	return err;
1758	}
1759
1760	int ip_getsockopt(struct sock *sk, int level,
1761	int optname, char __user *optval, int __user *optlen)
1762	{
1763	int err;
1764
1765	err = do_ip_getsockopt(sk, level, optname,
1766	optval: USER_SOCKPTR(p: optval), optlen: USER_SOCKPTR(p: optlen));
1767
1768	#ifdef CONFIG_NETFILTER
1769	/* we need to exclude all possible ENOPROTOOPTs except default case */
1770	if (err == -ENOPROTOOPT && optname != IP_PKTOPTIONS &&
1771	!ip_mroute_opt(opt: optname)) {
1772	int len;
1773
1774	if (get_user(len, optlen))
1775	return -EFAULT;
1776
1777	err = nf_getsockopt(sk, PF_INET, optval: optname, opt: optval, len: &len);
1778	if (err >= 0)
1779	err = put_user(len, optlen);
1780	return err;
1781	}
1782	#endif
1783	return err;
1784	}
1785	EXPORT_SYMBOL(ip_getsockopt);
1786