Linux Audio

Check our new training course

Loading...
v3.1
 
   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/route.h>
  37#include <net/xfrm.h>
  38#include <net/compat.h>
  39#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 
  40#include <net/transp_v6.h>
  41#endif
 
  42
  43#include <linux/errqueue.h>
  44#include <asm/uaccess.h>
  45
  46#define IP_CMSG_PKTINFO		1
  47#define IP_CMSG_TTL		2
  48#define IP_CMSG_TOS		4
  49#define IP_CMSG_RECVOPTS	8
  50#define IP_CMSG_RETOPTS		16
  51#define IP_CMSG_PASSSEC		32
  52#define IP_CMSG_ORIGDSTADDR     64
  53
  54/*
  55 *	SOL_IP control messages.
  56 */
  57
  58static void ip_cmsg_recv_pktinfo(struct msghdr *msg, struct sk_buff *skb)
  59{
  60	struct in_pktinfo info;
  61	struct rtable *rt = skb_rtable(skb);
  62
  63	info.ipi_addr.s_addr = ip_hdr(skb)->daddr;
  64	if (rt) {
  65		info.ipi_ifindex = rt->rt_iif;
  66		info.ipi_spec_dst.s_addr = rt->rt_spec_dst;
  67	} else {
  68		info.ipi_ifindex = 0;
  69		info.ipi_spec_dst.s_addr = 0;
  70	}
  71
  72	put_cmsg(msg, SOL_IP, IP_PKTINFO, sizeof(info), &info);
  73}
  74
  75static void ip_cmsg_recv_ttl(struct msghdr *msg, struct sk_buff *skb)
  76{
  77	int ttl = ip_hdr(skb)->ttl;
  78	put_cmsg(msg, SOL_IP, IP_TTL, sizeof(int), &ttl);
  79}
  80
  81static void ip_cmsg_recv_tos(struct msghdr *msg, struct sk_buff *skb)
  82{
  83	put_cmsg(msg, SOL_IP, IP_TOS, 1, &ip_hdr(skb)->tos);
  84}
  85
  86static void ip_cmsg_recv_opts(struct msghdr *msg, struct sk_buff *skb)
  87{
  88	if (IPCB(skb)->opt.optlen == 0)
  89		return;
  90
  91	put_cmsg(msg, SOL_IP, IP_RECVOPTS, IPCB(skb)->opt.optlen,
  92		 ip_hdr(skb) + 1);
  93}
  94
  95
  96static void ip_cmsg_recv_retopts(struct msghdr *msg, struct sk_buff *skb)
 
  97{
  98	unsigned char optbuf[sizeof(struct ip_options) + 40];
  99	struct ip_options * opt = (struct ip_options *)optbuf;
 100
 101	if (IPCB(skb)->opt.optlen == 0)
 102		return;
 103
 104	if (ip_options_echo(opt, skb)) {
 105		msg->msg_flags |= MSG_CTRUNC;
 106		return;
 107	}
 108	ip_options_undo(opt);
 109
 110	put_cmsg(msg, SOL_IP, IP_RETOPTS, opt->optlen, opt->__data);
 111}
 112
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 113static void ip_cmsg_recv_security(struct msghdr *msg, struct sk_buff *skb)
 114{
 115	char *secdata;
 116	u32 seclen, secid;
 117	int err;
 118
 119	err = security_socket_getpeersec_dgram(NULL, skb, &secid);
 120	if (err)
 121		return;
 122
 123	err = security_secid_to_secctx(secid, &secdata, &seclen);
 124	if (err)
 125		return;
 126
 127	put_cmsg(msg, SOL_IP, SCM_SECURITY, seclen, secdata);
 128	security_release_secctx(secdata, seclen);
 129}
 130
 131static void ip_cmsg_recv_dstaddr(struct msghdr *msg, struct sk_buff *skb)
 132{
 
 133	struct sockaddr_in sin;
 134	const struct iphdr *iph = ip_hdr(skb);
 135	__be16 *ports = (__be16 *)skb_transport_header(skb);
 136
 137	if (skb_transport_offset(skb) + 4 > skb->len)
 138		return;
 139
 140	/* All current transport protocols have the port numbers in the
 141	 * first four bytes of the transport header and this function is
 142	 * written with this assumption in mind.
 143	 */
 
 
 
 
 144
 145	sin.sin_family = AF_INET;
 146	sin.sin_addr.s_addr = iph->daddr;
 147	sin.sin_port = ports[1];
 148	memset(sin.sin_zero, 0, sizeof(sin.sin_zero));
 149
 150	put_cmsg(msg, SOL_IP, IP_ORIGDSTADDR, sizeof(sin), &sin);
 151}
 152
 153void ip_cmsg_recv(struct msghdr *msg, struct sk_buff *skb)
 
 154{
 155	struct inet_sock *inet = inet_sk(skb->sk);
 156	unsigned flags = inet->cmsg_flags;
 157
 158	/* Ordered by supposed usage frequency */
 159	if (flags & 1)
 160		ip_cmsg_recv_pktinfo(msg, skb);
 161	if ((flags >>= 1) == 0)
 162		return;
 163
 164	if (flags & 1)
 
 
 
 
 
 165		ip_cmsg_recv_ttl(msg, skb);
 166	if ((flags >>= 1) == 0)
 167		return;
 168
 169	if (flags & 1)
 
 
 
 
 
 170		ip_cmsg_recv_tos(msg, skb);
 171	if ((flags >>= 1) == 0)
 172		return;
 173
 174	if (flags & 1)
 
 
 
 
 
 175		ip_cmsg_recv_opts(msg, skb);
 176	if ((flags >>= 1) == 0)
 177		return;
 178
 179	if (flags & 1)
 180		ip_cmsg_recv_retopts(msg, skb);
 181	if ((flags >>= 1) == 0)
 182		return;
 
 
 
 183
 184	if (flags & 1)
 
 
 
 
 
 185		ip_cmsg_recv_security(msg, skb);
 186
 187	if ((flags >>= 1) == 0)
 188		return;
 189	if (flags & 1)
 
 
 
 190		ip_cmsg_recv_dstaddr(msg, skb);
 191
 
 
 
 
 
 
 
 
 
 
 192}
 193EXPORT_SYMBOL(ip_cmsg_recv);
 194
 195int ip_cmsg_send(struct net *net, struct msghdr *msg, struct ipcm_cookie *ipc)
 
 196{
 197	int err;
 198	struct cmsghdr *cmsg;
 
 199
 200	for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
 201		if (!CMSG_OK(msg, cmsg))
 202			return -EINVAL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 203		if (cmsg->cmsg_level != SOL_IP)
 204			continue;
 205		switch (cmsg->cmsg_type) {
 206		case IP_RETOPTS:
 207			err = cmsg->cmsg_len - CMSG_ALIGN(sizeof(struct cmsghdr));
 
 
 208			err = ip_options_get(net, &ipc->opt, CMSG_DATA(cmsg),
 209					     err < 40 ? err : 40);
 210			if (err)
 211				return err;
 212			break;
 213		case IP_PKTINFO:
 214		{
 215			struct in_pktinfo *info;
 216			if (cmsg->cmsg_len != CMSG_LEN(sizeof(struct in_pktinfo)))
 217				return -EINVAL;
 218			info = (struct in_pktinfo *)CMSG_DATA(cmsg);
 219			ipc->oif = info->ipi_ifindex;
 
 220			ipc->addr = info->ipi_spec_dst.s_addr;
 221			break;
 222		}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 223		default:
 224			return -EINVAL;
 225		}
 226	}
 227	return 0;
 228}
 229
 230
 231/* Special input handler for packets caught by router alert option.
 232   They are selected only by protocol field, and then processed likely
 233   local ones; but only if someone wants them! Otherwise, router
 234   not running rsvpd will kill RSVP.
 235
 236   It is user level problem, what it will make with them.
 237   I have no idea, how it will masquearde or NAT them (it is joke, joke :-)),
 238   but receiver should be enough clever f.e. to forward mtrace requests,
 239   sent to multicast group to reach destination designated router.
 240 */
 241struct ip_ra_chain __rcu *ip_ra_chain;
 242static DEFINE_SPINLOCK(ip_ra_lock);
 243
 244
 245static void ip_ra_destroy_rcu(struct rcu_head *head)
 246{
 247	struct ip_ra_chain *ra = container_of(head, struct ip_ra_chain, rcu);
 248
 249	sock_put(ra->saved_sk);
 250	kfree(ra);
 251}
 252
 253int ip_ra_control(struct sock *sk, unsigned char on,
 254		  void (*destructor)(struct sock *))
 255{
 256	struct ip_ra_chain *ra, *new_ra;
 257	struct ip_ra_chain __rcu **rap;
 
 258
 259	if (sk->sk_type != SOCK_RAW || inet_sk(sk)->inet_num == IPPROTO_RAW)
 260		return -EINVAL;
 261
 262	new_ra = on ? kmalloc(sizeof(*new_ra), GFP_KERNEL) : NULL;
 
 
 263
 264	spin_lock_bh(&ip_ra_lock);
 265	for (rap = &ip_ra_chain;
 266	     (ra = rcu_dereference_protected(*rap,
 267			lockdep_is_held(&ip_ra_lock))) != NULL;
 268	     rap = &ra->next) {
 269		if (ra->sk == sk) {
 270			if (on) {
 271				spin_unlock_bh(&ip_ra_lock);
 272				kfree(new_ra);
 273				return -EADDRINUSE;
 274			}
 275			/* dont let ip_call_ra_chain() use sk again */
 276			ra->sk = NULL;
 277			rcu_assign_pointer(*rap, ra->next);
 278			spin_unlock_bh(&ip_ra_lock);
 279
 280			if (ra->destructor)
 281				ra->destructor(sk);
 282			/*
 283			 * Delay sock_put(sk) and kfree(ra) after one rcu grace
 284			 * period. This guarantee ip_call_ra_chain() dont need
 285			 * to mess with socket refcounts.
 286			 */
 287			ra->saved_sk = sk;
 288			call_rcu(&ra->rcu, ip_ra_destroy_rcu);
 289			return 0;
 290		}
 291	}
 292	if (new_ra == NULL) {
 293		spin_unlock_bh(&ip_ra_lock);
 294		return -ENOBUFS;
 295	}
 296	new_ra->sk = sk;
 297	new_ra->destructor = destructor;
 298
 299	new_ra->next = ra;
 300	rcu_assign_pointer(*rap, new_ra);
 301	sock_hold(sk);
 302	spin_unlock_bh(&ip_ra_lock);
 303
 304	return 0;
 305}
 306
 307void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
 308		   __be16 port, u32 info, u8 *payload)
 309{
 310	struct sock_exterr_skb *serr;
 311
 312	skb = skb_clone(skb, GFP_ATOMIC);
 313	if (!skb)
 314		return;
 315
 316	serr = SKB_EXT_ERR(skb);
 317	serr->ee.ee_errno = err;
 318	serr->ee.ee_origin = SO_EE_ORIGIN_ICMP;
 319	serr->ee.ee_type = icmp_hdr(skb)->type;
 320	serr->ee.ee_code = icmp_hdr(skb)->code;
 321	serr->ee.ee_pad = 0;
 322	serr->ee.ee_info = info;
 323	serr->ee.ee_data = 0;
 324	serr->addr_offset = (u8 *)&(((struct iphdr *)(icmp_hdr(skb) + 1))->daddr) -
 325				   skb_network_header(skb);
 326	serr->port = port;
 327
 328	if (skb_pull(skb, payload - skb->data) != NULL) {
 329		skb_reset_transport_header(skb);
 330		if (sock_queue_err_skb(sk, skb) == 0)
 331			return;
 332	}
 333	kfree_skb(skb);
 334}
 335
 336void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 port, u32 info)
 337{
 338	struct inet_sock *inet = inet_sk(sk);
 339	struct sock_exterr_skb *serr;
 340	struct iphdr *iph;
 341	struct sk_buff *skb;
 342
 343	if (!inet->recverr)
 344		return;
 345
 346	skb = alloc_skb(sizeof(struct iphdr), GFP_ATOMIC);
 347	if (!skb)
 348		return;
 349
 350	skb_put(skb, sizeof(struct iphdr));
 351	skb_reset_network_header(skb);
 352	iph = ip_hdr(skb);
 353	iph->daddr = daddr;
 354
 355	serr = SKB_EXT_ERR(skb);
 356	serr->ee.ee_errno = err;
 357	serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
 358	serr->ee.ee_type = 0;
 359	serr->ee.ee_code = 0;
 360	serr->ee.ee_pad = 0;
 361	serr->ee.ee_info = info;
 362	serr->ee.ee_data = 0;
 363	serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
 364	serr->port = port;
 365
 366	__skb_pull(skb, skb_tail_pointer(skb) - skb->data);
 367	skb_reset_transport_header(skb);
 368
 369	if (sock_queue_err_skb(sk, skb))
 370		kfree_skb(skb);
 371}
 372
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 373/*
 374 *	Handle MSG_ERRQUEUE
 375 */
 376int ip_recv_error(struct sock *sk, struct msghdr *msg, int len)
 377{
 378	struct sock_exterr_skb *serr;
 379	struct sk_buff *skb, *skb2;
 380	struct sockaddr_in *sin;
 381	struct {
 382		struct sock_extended_err ee;
 383		struct sockaddr_in	 offender;
 384	} errhdr;
 385	int err;
 386	int copied;
 387
 388	err = -EAGAIN;
 389	skb = skb_dequeue(&sk->sk_error_queue);
 390	if (skb == NULL)
 391		goto out;
 392
 393	copied = skb->len;
 394	if (copied > len) {
 395		msg->msg_flags |= MSG_TRUNC;
 396		copied = len;
 397	}
 398	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
 399	if (err)
 400		goto out_free_skb;
 401
 
 402	sock_recv_timestamp(msg, sk, skb);
 403
 404	serr = SKB_EXT_ERR(skb);
 405
 406	sin = (struct sockaddr_in *)msg->msg_name;
 407	if (sin) {
 408		sin->sin_family = AF_INET;
 409		sin->sin_addr.s_addr = *(__be32 *)(skb_network_header(skb) +
 410						   serr->addr_offset);
 411		sin->sin_port = serr->port;
 412		memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
 
 413	}
 414
 415	memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
 416	sin = &errhdr.offender;
 417	sin->sin_family = AF_UNSPEC;
 418	if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP) {
 419		struct inet_sock *inet = inet_sk(sk);
 420
 
 421		sin->sin_family = AF_INET;
 422		sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
 423		sin->sin_port = 0;
 424		memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
 425		if (inet->cmsg_flags)
 426			ip_cmsg_recv(msg, skb);
 427	}
 428
 429	put_cmsg(msg, SOL_IP, IP_RECVERR, sizeof(errhdr), &errhdr);
 430
 431	/* Now we could try to dump offended packet options */
 432
 433	msg->msg_flags |= MSG_ERRQUEUE;
 434	err = copied;
 435
 436	/* Reset and regenerate socket error */
 437	spin_lock_bh(&sk->sk_error_queue.lock);
 438	sk->sk_err = 0;
 439	skb2 = skb_peek(&sk->sk_error_queue);
 440	if (skb2 != NULL) {
 441		sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
 442		spin_unlock_bh(&sk->sk_error_queue.lock);
 443		sk->sk_error_report(sk);
 444	} else
 445		spin_unlock_bh(&sk->sk_error_queue.lock);
 446
 447out_free_skb:
 448	kfree_skb(skb);
 449out:
 450	return err;
 451}
 452
 453
 454static void opt_kfree_rcu(struct rcu_head *head)
 455{
 456	kfree(container_of(head, struct ip_options_rcu, rcu));
 457}
 458
 459/*
 460 *	Socket option code for IP. This is the end of the line after any
 461 *	TCP,UDP etc options on an IP socket.
 462 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 463
 464static int do_ip_setsockopt(struct sock *sk, int level,
 465			    int optname, char __user *optval, unsigned int optlen)
 466{
 467	struct inet_sock *inet = inet_sk(sk);
 
 468	int val = 0, err;
 
 469
 470	if (((1<<optname) & ((1<<IP_PKTINFO) | (1<<IP_RECVTTL) |
 471			     (1<<IP_RECVOPTS) | (1<<IP_RECVTOS) |
 472			     (1<<IP_RETOPTS) | (1<<IP_TOS) |
 473			     (1<<IP_TTL) | (1<<IP_HDRINCL) |
 474			     (1<<IP_MTU_DISCOVER) | (1<<IP_RECVERR) |
 475			     (1<<IP_ROUTER_ALERT) | (1<<IP_FREEBIND) |
 476			     (1<<IP_PASSSEC) | (1<<IP_TRANSPARENT) |
 477			     (1<<IP_MINTTL) | (1<<IP_NODEFRAG))) ||
 478	    optname == IP_MULTICAST_TTL ||
 479	    optname == IP_MULTICAST_ALL ||
 480	    optname == IP_MULTICAST_LOOP ||
 481	    optname == IP_RECVORIGDSTADDR) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 482		if (optlen >= sizeof(int)) {
 483			if (get_user(val, (int __user *) optval))
 484				return -EFAULT;
 485		} else if (optlen >= sizeof(char)) {
 486			unsigned char ucval;
 487
 488			if (get_user(ucval, (unsigned char __user *) optval))
 489				return -EFAULT;
 490			val = (int) ucval;
 491		}
 492	}
 493
 494	/* If optlen==0, it is equivalent to val == 0 */
 495
 
 
 496	if (ip_mroute_opt(optname))
 497		return ip_mroute_setsockopt(sk, optname, optval, optlen);
 498
 499	err = 0;
 
 
 500	lock_sock(sk);
 501
 502	switch (optname) {
 503	case IP_OPTIONS:
 504	{
 505		struct ip_options_rcu *old, *opt = NULL;
 506
 507		if (optlen > 40)
 508			goto e_inval;
 509		err = ip_options_get_from_user(sock_net(sk), &opt,
 510					       optval, optlen);
 511		if (err)
 512			break;
 513		old = rcu_dereference_protected(inet->inet_opt,
 514						sock_owned_by_user(sk));
 515		if (inet->is_icsk) {
 516			struct inet_connection_sock *icsk = inet_csk(sk);
 517#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 518			if (sk->sk_family == PF_INET ||
 519			    (!((1 << sk->sk_state) &
 520			       (TCPF_LISTEN | TCPF_CLOSE)) &&
 521			     inet->inet_daddr != LOOPBACK4_IPV6)) {
 522#endif
 523				if (old)
 524					icsk->icsk_ext_hdr_len -= old->opt.optlen;
 525				if (opt)
 526					icsk->icsk_ext_hdr_len += opt->opt.optlen;
 527				icsk->icsk_sync_mss(sk, icsk->icsk_pmtu_cookie);
 528#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 529			}
 530#endif
 531		}
 532		rcu_assign_pointer(inet->inet_opt, opt);
 533		if (old)
 534			call_rcu(&old->rcu, opt_kfree_rcu);
 535		break;
 536	}
 537	case IP_PKTINFO:
 538		if (val)
 539			inet->cmsg_flags |= IP_CMSG_PKTINFO;
 540		else
 541			inet->cmsg_flags &= ~IP_CMSG_PKTINFO;
 542		break;
 543	case IP_RECVTTL:
 544		if (val)
 545			inet->cmsg_flags |=  IP_CMSG_TTL;
 546		else
 547			inet->cmsg_flags &= ~IP_CMSG_TTL;
 548		break;
 549	case IP_RECVTOS:
 550		if (val)
 551			inet->cmsg_flags |=  IP_CMSG_TOS;
 552		else
 553			inet->cmsg_flags &= ~IP_CMSG_TOS;
 554		break;
 555	case IP_RECVOPTS:
 556		if (val)
 557			inet->cmsg_flags |=  IP_CMSG_RECVOPTS;
 558		else
 559			inet->cmsg_flags &= ~IP_CMSG_RECVOPTS;
 560		break;
 561	case IP_RETOPTS:
 562		if (val)
 563			inet->cmsg_flags |= IP_CMSG_RETOPTS;
 564		else
 565			inet->cmsg_flags &= ~IP_CMSG_RETOPTS;
 566		break;
 567	case IP_PASSSEC:
 568		if (val)
 569			inet->cmsg_flags |= IP_CMSG_PASSSEC;
 570		else
 571			inet->cmsg_flags &= ~IP_CMSG_PASSSEC;
 572		break;
 573	case IP_RECVORIGDSTADDR:
 574		if (val)
 575			inet->cmsg_flags |= IP_CMSG_ORIGDSTADDR;
 576		else
 577			inet->cmsg_flags &= ~IP_CMSG_ORIGDSTADDR;
 578		break;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 579	case IP_TOS:	/* This sets both TOS and Precedence */
 580		if (sk->sk_type == SOCK_STREAM) {
 581			val &= ~3;
 582			val |= inet->tos & 3;
 583		}
 584		if (inet->tos != val) {
 585			inet->tos = val;
 586			sk->sk_priority = rt_tos2priority(val);
 587			sk_dst_reset(sk);
 588		}
 589		break;
 590	case IP_TTL:
 591		if (optlen < 1)
 592			goto e_inval;
 593		if (val != -1 && (val < 0 || val > 255))
 594			goto e_inval;
 595		inet->uc_ttl = val;
 596		break;
 597	case IP_HDRINCL:
 598		if (sk->sk_type != SOCK_RAW) {
 599			err = -ENOPROTOOPT;
 600			break;
 601		}
 602		inet->hdrincl = val ? 1 : 0;
 603		break;
 604	case IP_NODEFRAG:
 605		if (sk->sk_type != SOCK_RAW) {
 606			err = -ENOPROTOOPT;
 607			break;
 608		}
 609		inet->nodefrag = val ? 1 : 0;
 610		break;
 
 
 
 611	case IP_MTU_DISCOVER:
 612		if (val < IP_PMTUDISC_DONT || val > IP_PMTUDISC_PROBE)
 613			goto e_inval;
 614		inet->pmtudisc = val;
 615		break;
 616	case IP_RECVERR:
 617		inet->recverr = !!val;
 618		if (!val)
 619			skb_queue_purge(&sk->sk_error_queue);
 620		break;
 621	case IP_MULTICAST_TTL:
 622		if (sk->sk_type == SOCK_STREAM)
 623			goto e_inval;
 624		if (optlen < 1)
 625			goto e_inval;
 626		if (val == -1)
 627			val = 1;
 628		if (val < 0 || val > 255)
 629			goto e_inval;
 630		inet->mc_ttl = val;
 631		break;
 632	case IP_MULTICAST_LOOP:
 633		if (optlen < 1)
 634			goto e_inval;
 635		inet->mc_loop = !!val;
 636		break;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 637	case IP_MULTICAST_IF:
 638	{
 639		struct ip_mreqn mreq;
 640		struct net_device *dev = NULL;
 
 641
 642		if (sk->sk_type == SOCK_STREAM)
 643			goto e_inval;
 644		/*
 645		 *	Check the arguments are allowable
 646		 */
 647
 648		if (optlen < sizeof(struct in_addr))
 649			goto e_inval;
 650
 651		err = -EFAULT;
 652		if (optlen >= sizeof(struct ip_mreqn)) {
 653			if (copy_from_user(&mreq, optval, sizeof(mreq)))
 654				break;
 655		} else {
 656			memset(&mreq, 0, sizeof(mreq));
 657			if (optlen >= sizeof(struct in_addr) &&
 658			    copy_from_user(&mreq.imr_address, optval,
 659					   sizeof(struct in_addr)))
 660				break;
 
 
 
 
 
 661		}
 662
 663		if (!mreq.imr_ifindex) {
 664			if (mreq.imr_address.s_addr == htonl(INADDR_ANY)) {
 665				inet->mc_index = 0;
 666				inet->mc_addr  = 0;
 667				err = 0;
 668				break;
 669			}
 670			dev = ip_dev_find(sock_net(sk), mreq.imr_address.s_addr);
 671			if (dev)
 672				mreq.imr_ifindex = dev->ifindex;
 673		} else
 674			dev = dev_get_by_index(sock_net(sk), mreq.imr_ifindex);
 675
 676
 677		err = -EADDRNOTAVAIL;
 678		if (!dev)
 679			break;
 
 
 
 680		dev_put(dev);
 681
 682		err = -EINVAL;
 683		if (sk->sk_bound_dev_if &&
 684		    mreq.imr_ifindex != sk->sk_bound_dev_if)
 
 685			break;
 686
 687		inet->mc_index = mreq.imr_ifindex;
 688		inet->mc_addr  = mreq.imr_address.s_addr;
 689		err = 0;
 690		break;
 691	}
 692
 693	case IP_ADD_MEMBERSHIP:
 694	case IP_DROP_MEMBERSHIP:
 695	{
 696		struct ip_mreqn mreq;
 697
 698		err = -EPROTO;
 699		if (inet_sk(sk)->is_icsk)
 700			break;
 701
 702		if (optlen < sizeof(struct ip_mreq))
 703			goto e_inval;
 704		err = -EFAULT;
 705		if (optlen >= sizeof(struct ip_mreqn)) {
 706			if (copy_from_user(&mreq, optval, sizeof(mreq)))
 707				break;
 708		} else {
 709			memset(&mreq, 0, sizeof(mreq));
 710			if (copy_from_user(&mreq, optval, sizeof(struct ip_mreq)))
 711				break;
 712		}
 713
 714		if (optname == IP_ADD_MEMBERSHIP)
 715			err = ip_mc_join_group(sk, &mreq);
 716		else
 717			err = ip_mc_leave_group(sk, &mreq);
 718		break;
 719	}
 720	case IP_MSFILTER:
 721	{
 722		struct ip_msfilter *msf;
 723
 724		if (optlen < IP_MSFILTER_SIZE(0))
 725			goto e_inval;
 726		if (optlen > sysctl_optmem_max) {
 727			err = -ENOBUFS;
 728			break;
 729		}
 730		msf = kmalloc(optlen, GFP_KERNEL);
 731		if (!msf) {
 732			err = -ENOBUFS;
 733			break;
 734		}
 735		err = -EFAULT;
 736		if (copy_from_user(msf, optval, optlen)) {
 737			kfree(msf);
 738			break;
 739		}
 740		/* numsrc >= (1G-4) overflow in 32 bits */
 741		if (msf->imsf_numsrc >= 0x3ffffffcU ||
 742		    msf->imsf_numsrc > sysctl_igmp_max_msf) {
 743			kfree(msf);
 744			err = -ENOBUFS;
 745			break;
 746		}
 747		if (IP_MSFILTER_SIZE(msf->imsf_numsrc) > optlen) {
 748			kfree(msf);
 749			err = -EINVAL;
 750			break;
 751		}
 752		err = ip_mc_msfilter(sk, msf, 0);
 753		kfree(msf);
 754		break;
 755	}
 756	case IP_BLOCK_SOURCE:
 757	case IP_UNBLOCK_SOURCE:
 758	case IP_ADD_SOURCE_MEMBERSHIP:
 759	case IP_DROP_SOURCE_MEMBERSHIP:
 760	{
 761		struct ip_mreq_source mreqs;
 762		int omode, add;
 763
 764		if (optlen != sizeof(struct ip_mreq_source))
 765			goto e_inval;
 766		if (copy_from_user(&mreqs, optval, sizeof(mreqs))) {
 767			err = -EFAULT;
 768			break;
 769		}
 770		if (optname == IP_BLOCK_SOURCE) {
 771			omode = MCAST_EXCLUDE;
 772			add = 1;
 773		} else if (optname == IP_UNBLOCK_SOURCE) {
 774			omode = MCAST_EXCLUDE;
 775			add = 0;
 776		} else if (optname == IP_ADD_SOURCE_MEMBERSHIP) {
 777			struct ip_mreqn mreq;
 778
 779			mreq.imr_multiaddr.s_addr = mreqs.imr_multiaddr;
 780			mreq.imr_address.s_addr = mreqs.imr_interface;
 781			mreq.imr_ifindex = 0;
 782			err = ip_mc_join_group(sk, &mreq);
 783			if (err && err != -EADDRINUSE)
 784				break;
 785			omode = MCAST_INCLUDE;
 786			add = 1;
 787		} else /* IP_DROP_SOURCE_MEMBERSHIP */ {
 788			omode = MCAST_INCLUDE;
 789			add = 0;
 790		}
 791		err = ip_mc_source(add, omode, sk, &mreqs, 0);
 792		break;
 793	}
 794	case MCAST_JOIN_GROUP:
 795	case MCAST_LEAVE_GROUP:
 796	{
 797		struct group_req greq;
 798		struct sockaddr_in *psin;
 799		struct ip_mreqn mreq;
 800
 801		if (optlen < sizeof(struct group_req))
 802			goto e_inval;
 803		err = -EFAULT;
 804		if (copy_from_user(&greq, optval, sizeof(greq)))
 805			break;
 806		psin = (struct sockaddr_in *)&greq.gr_group;
 807		if (psin->sin_family != AF_INET)
 808			goto e_inval;
 809		memset(&mreq, 0, sizeof(mreq));
 810		mreq.imr_multiaddr = psin->sin_addr;
 811		mreq.imr_ifindex = greq.gr_interface;
 812
 813		if (optname == MCAST_JOIN_GROUP)
 814			err = ip_mc_join_group(sk, &mreq);
 815		else
 816			err = ip_mc_leave_group(sk, &mreq);
 817		break;
 818	}
 819	case MCAST_JOIN_SOURCE_GROUP:
 820	case MCAST_LEAVE_SOURCE_GROUP:
 821	case MCAST_BLOCK_SOURCE:
 822	case MCAST_UNBLOCK_SOURCE:
 823	{
 824		struct group_source_req greqs;
 825		struct ip_mreq_source mreqs;
 826		struct sockaddr_in *psin;
 827		int omode, add;
 828
 829		if (optlen != sizeof(struct group_source_req))
 830			goto e_inval;
 831		if (copy_from_user(&greqs, optval, sizeof(greqs))) {
 832			err = -EFAULT;
 833			break;
 834		}
 835		if (greqs.gsr_group.ss_family != AF_INET ||
 836		    greqs.gsr_source.ss_family != AF_INET) {
 837			err = -EADDRNOTAVAIL;
 838			break;
 839		}
 840		psin = (struct sockaddr_in *)&greqs.gsr_group;
 841		mreqs.imr_multiaddr = psin->sin_addr.s_addr;
 842		psin = (struct sockaddr_in *)&greqs.gsr_source;
 843		mreqs.imr_sourceaddr = psin->sin_addr.s_addr;
 844		mreqs.imr_interface = 0; /* use index for mc_source */
 845
 846		if (optname == MCAST_BLOCK_SOURCE) {
 847			omode = MCAST_EXCLUDE;
 848			add = 1;
 849		} else if (optname == MCAST_UNBLOCK_SOURCE) {
 850			omode = MCAST_EXCLUDE;
 851			add = 0;
 852		} else if (optname == MCAST_JOIN_SOURCE_GROUP) {
 853			struct ip_mreqn mreq;
 854
 855			psin = (struct sockaddr_in *)&greqs.gsr_group;
 856			mreq.imr_multiaddr = psin->sin_addr;
 857			mreq.imr_address.s_addr = 0;
 858			mreq.imr_ifindex = greqs.gsr_interface;
 859			err = ip_mc_join_group(sk, &mreq);
 860			if (err && err != -EADDRINUSE)
 861				break;
 862			greqs.gsr_interface = mreq.imr_ifindex;
 863			omode = MCAST_INCLUDE;
 864			add = 1;
 865		} else /* MCAST_LEAVE_SOURCE_GROUP */ {
 866			omode = MCAST_INCLUDE;
 867			add = 0;
 868		}
 869		err = ip_mc_source(add, omode, sk, &mreqs,
 870				   greqs.gsr_interface);
 871		break;
 872	}
 873	case MCAST_MSFILTER:
 874	{
 875		struct sockaddr_in *psin;
 876		struct ip_msfilter *msf = NULL;
 877		struct group_filter *gsf = NULL;
 878		int msize, i, ifindex;
 879
 880		if (optlen < GROUP_FILTER_SIZE(0))
 881			goto e_inval;
 882		if (optlen > sysctl_optmem_max) {
 883			err = -ENOBUFS;
 884			break;
 885		}
 886		gsf = kmalloc(optlen, GFP_KERNEL);
 887		if (!gsf) {
 888			err = -ENOBUFS;
 889			break;
 890		}
 891		err = -EFAULT;
 892		if (copy_from_user(gsf, optval, optlen))
 893			goto mc_msf_out;
 894
 895		/* numsrc >= (4G-140)/128 overflow in 32 bits */
 896		if (gsf->gf_numsrc >= 0x1ffffff ||
 897		    gsf->gf_numsrc > sysctl_igmp_max_msf) {
 898			err = -ENOBUFS;
 899			goto mc_msf_out;
 900		}
 901		if (GROUP_FILTER_SIZE(gsf->gf_numsrc) > optlen) {
 902			err = -EINVAL;
 903			goto mc_msf_out;
 904		}
 905		msize = IP_MSFILTER_SIZE(gsf->gf_numsrc);
 906		msf = kmalloc(msize, GFP_KERNEL);
 907		if (!msf) {
 908			err = -ENOBUFS;
 909			goto mc_msf_out;
 910		}
 911		ifindex = gsf->gf_interface;
 912		psin = (struct sockaddr_in *)&gsf->gf_group;
 913		if (psin->sin_family != AF_INET) {
 914			err = -EADDRNOTAVAIL;
 915			goto mc_msf_out;
 916		}
 917		msf->imsf_multiaddr = psin->sin_addr.s_addr;
 918		msf->imsf_interface = 0;
 919		msf->imsf_fmode = gsf->gf_fmode;
 920		msf->imsf_numsrc = gsf->gf_numsrc;
 921		err = -EADDRNOTAVAIL;
 922		for (i = 0; i < gsf->gf_numsrc; ++i) {
 923			psin = (struct sockaddr_in *)&gsf->gf_slist[i];
 924
 925			if (psin->sin_family != AF_INET)
 926				goto mc_msf_out;
 927			msf->imsf_slist[i] = psin->sin_addr.s_addr;
 928		}
 929		kfree(gsf);
 930		gsf = NULL;
 931
 932		err = ip_mc_msfilter(sk, msf, ifindex);
 933mc_msf_out:
 934		kfree(msf);
 935		kfree(gsf);
 936		break;
 937	}
 938	case IP_MULTICAST_ALL:
 939		if (optlen < 1)
 940			goto e_inval;
 941		if (val != 0 && val != 1)
 942			goto e_inval;
 943		inet->mc_all = val;
 944		break;
 945	case IP_ROUTER_ALERT:
 946		err = ip_ra_control(sk, val ? 1 : 0, NULL);
 947		break;
 948
 949	case IP_FREEBIND:
 950		if (optlen < 1)
 951			goto e_inval;
 952		inet->freebind = !!val;
 953		break;
 954
 955	case IP_IPSEC_POLICY:
 956	case IP_XFRM_POLICY:
 957		err = -EPERM;
 958		if (!capable(CAP_NET_ADMIN))
 959			break;
 960		err = xfrm_user_policy(sk, optname, optval, optlen);
 961		break;
 962
 963	case IP_TRANSPARENT:
 964		if (!capable(CAP_NET_ADMIN)) {
 
 965			err = -EPERM;
 966			break;
 967		}
 968		if (optlen < 1)
 969			goto e_inval;
 970		inet->transparent = !!val;
 971		break;
 972
 973	case IP_MINTTL:
 974		if (optlen < 1)
 975			goto e_inval;
 976		if (val < 0 || val > 255)
 977			goto e_inval;
 978		inet->min_ttl = val;
 979		break;
 980
 981	default:
 982		err = -ENOPROTOOPT;
 983		break;
 984	}
 985	release_sock(sk);
 
 
 986	return err;
 987
 988e_inval:
 989	release_sock(sk);
 
 
 990	return -EINVAL;
 991}
 992
 993/**
 994 * ip_queue_rcv_skb - Queue an skb into sock receive queue
 995 * @sk: socket
 996 * @skb: buffer
 997 *
 998 * Queues an skb into socket receive queue. If IP_CMSG_PKTINFO option
 999 * is not set, we drop skb dst entry now, while dst cache line is hot.
 
1000 */
1001int ip_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
1002{
1003	if (!(inet_sk(sk)->cmsg_flags & IP_CMSG_PKTINFO))
1004		skb_dst_drop(skb);
1005	return sock_queue_rcv_skb(sk, skb);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1006}
1007EXPORT_SYMBOL(ip_queue_rcv_skb);
1008
1009int ip_setsockopt(struct sock *sk, int level,
1010		int optname, char __user *optval, unsigned int optlen)
1011{
1012	int err;
1013
1014	if (level != SOL_IP)
1015		return -ENOPROTOOPT;
1016
1017	err = do_ip_setsockopt(sk, level, optname, optval, optlen);
 
 
 
 
 
1018#ifdef CONFIG_NETFILTER
1019	/* we need to exclude all possible ENOPROTOOPTs except default case */
1020	if (err == -ENOPROTOOPT && optname != IP_HDRINCL &&
1021			optname != IP_IPSEC_POLICY &&
1022			optname != IP_XFRM_POLICY &&
1023			!ip_mroute_opt(optname)) {
1024		lock_sock(sk);
1025		err = nf_setsockopt(sk, PF_INET, optname, optval, optlen);
1026		release_sock(sk);
1027	}
1028#endif
1029	return err;
1030}
1031EXPORT_SYMBOL(ip_setsockopt);
1032
1033#ifdef CONFIG_COMPAT
1034int compat_ip_setsockopt(struct sock *sk, int level, int optname,
1035			 char __user *optval, unsigned int optlen)
1036{
1037	int err;
1038
1039	if (level != SOL_IP)
1040		return -ENOPROTOOPT;
1041
1042	if (optname >= MCAST_JOIN_GROUP && optname <= MCAST_MSFILTER)
1043		return compat_mc_setsockopt(sk, level, optname, optval, optlen,
1044			ip_setsockopt);
1045
1046	err = do_ip_setsockopt(sk, level, optname, optval, optlen);
1047#ifdef CONFIG_NETFILTER
1048	/* we need to exclude all possible ENOPROTOOPTs except default case */
1049	if (err == -ENOPROTOOPT && optname != IP_HDRINCL &&
1050			optname != IP_IPSEC_POLICY &&
1051			optname != IP_XFRM_POLICY &&
1052			!ip_mroute_opt(optname)) {
1053		lock_sock(sk);
1054		err = compat_nf_setsockopt(sk, PF_INET, optname,
1055					   optval, optlen);
1056		release_sock(sk);
1057	}
1058#endif
1059	return err;
1060}
1061EXPORT_SYMBOL(compat_ip_setsockopt);
1062#endif
1063
1064/*
1065 *	Get the options. Note for future reference. The GET of IP options gets
1066 *	the _received_ ones. The set sets the _sent_ ones.
1067 */
1068
 
 
 
 
 
 
 
 
 
 
1069static int do_ip_getsockopt(struct sock *sk, int level, int optname,
1070			    char __user *optval, int __user *optlen, unsigned flags)
1071{
1072	struct inet_sock *inet = inet_sk(sk);
1073	int val;
 
1074	int len;
1075
1076	if (level != SOL_IP)
1077		return -EOPNOTSUPP;
1078
1079	if (ip_mroute_opt(optname))
1080		return ip_mroute_getsockopt(sk, optname, optval, optlen);
1081
1082	if (get_user(len, optlen))
1083		return -EFAULT;
1084	if (len < 0)
1085		return -EINVAL;
1086
 
 
1087	lock_sock(sk);
1088
1089	switch (optname) {
1090	case IP_OPTIONS:
1091	{
1092		unsigned char optbuf[sizeof(struct ip_options)+40];
1093		struct ip_options *opt = (struct ip_options *)optbuf;
1094		struct ip_options_rcu *inet_opt;
1095
1096		inet_opt = rcu_dereference_protected(inet->inet_opt,
1097						     sock_owned_by_user(sk));
1098		opt->optlen = 0;
1099		if (inet_opt)
1100			memcpy(optbuf, &inet_opt->opt,
1101			       sizeof(struct ip_options) +
1102			       inet_opt->opt.optlen);
1103		release_sock(sk);
1104
1105		if (opt->optlen == 0)
1106			return put_user(0, optlen);
1107
1108		ip_options_undo(opt);
1109
1110		len = min_t(unsigned int, len, opt->optlen);
1111		if (put_user(len, optlen))
1112			return -EFAULT;
1113		if (copy_to_user(optval, opt->__data, len))
1114			return -EFAULT;
1115		return 0;
1116	}
1117	case IP_PKTINFO:
1118		val = (inet->cmsg_flags & IP_CMSG_PKTINFO) != 0;
1119		break;
1120	case IP_RECVTTL:
1121		val = (inet->cmsg_flags & IP_CMSG_TTL) != 0;
1122		break;
1123	case IP_RECVTOS:
1124		val = (inet->cmsg_flags & IP_CMSG_TOS) != 0;
1125		break;
1126	case IP_RECVOPTS:
1127		val = (inet->cmsg_flags & IP_CMSG_RECVOPTS) != 0;
1128		break;
1129	case IP_RETOPTS:
1130		val = (inet->cmsg_flags & IP_CMSG_RETOPTS) != 0;
1131		break;
1132	case IP_PASSSEC:
1133		val = (inet->cmsg_flags & IP_CMSG_PASSSEC) != 0;
1134		break;
1135	case IP_RECVORIGDSTADDR:
1136		val = (inet->cmsg_flags & IP_CMSG_ORIGDSTADDR) != 0;
1137		break;
 
 
 
 
 
 
1138	case IP_TOS:
1139		val = inet->tos;
1140		break;
1141	case IP_TTL:
 
 
1142		val = (inet->uc_ttl == -1 ?
1143		       sysctl_ip_default_ttl :
1144		       inet->uc_ttl);
1145		break;
 
1146	case IP_HDRINCL:
1147		val = inet->hdrincl;
1148		break;
1149	case IP_NODEFRAG:
1150		val = inet->nodefrag;
1151		break;
 
 
 
1152	case IP_MTU_DISCOVER:
1153		val = inet->pmtudisc;
1154		break;
1155	case IP_MTU:
1156	{
1157		struct dst_entry *dst;
1158		val = 0;
1159		dst = sk_dst_get(sk);
1160		if (dst) {
1161			val = dst_mtu(dst);
1162			dst_release(dst);
1163		}
1164		if (!val) {
1165			release_sock(sk);
1166			return -ENOTCONN;
1167		}
1168		break;
1169	}
1170	case IP_RECVERR:
1171		val = inet->recverr;
1172		break;
1173	case IP_MULTICAST_TTL:
1174		val = inet->mc_ttl;
1175		break;
1176	case IP_MULTICAST_LOOP:
1177		val = inet->mc_loop;
1178		break;
 
 
 
1179	case IP_MULTICAST_IF:
1180	{
1181		struct in_addr addr;
1182		len = min_t(unsigned int, len, sizeof(struct in_addr));
1183		addr.s_addr = inet->mc_addr;
1184		release_sock(sk);
1185
1186		if (put_user(len, optlen))
1187			return -EFAULT;
1188		if (copy_to_user(optval, &addr, len))
1189			return -EFAULT;
1190		return 0;
1191	}
1192	case IP_MSFILTER:
1193	{
1194		struct ip_msfilter msf;
1195		int err;
1196
1197		if (len < IP_MSFILTER_SIZE(0)) {
1198			release_sock(sk);
1199			return -EINVAL;
1200		}
1201		if (copy_from_user(&msf, optval, IP_MSFILTER_SIZE(0))) {
1202			release_sock(sk);
1203			return -EFAULT;
1204		}
1205		err = ip_mc_msfget(sk, &msf,
1206				   (struct ip_msfilter __user *)optval, optlen);
1207		release_sock(sk);
1208		return err;
1209	}
1210	case MCAST_MSFILTER:
1211	{
1212		struct group_filter gsf;
1213		int err;
1214
1215		if (len < GROUP_FILTER_SIZE(0)) {
1216			release_sock(sk);
1217			return -EINVAL;
1218		}
1219		if (copy_from_user(&gsf, optval, GROUP_FILTER_SIZE(0))) {
1220			release_sock(sk);
1221			return -EFAULT;
1222		}
1223		err = ip_mc_gsfget(sk, &gsf,
1224				   (struct group_filter __user *)optval,
1225				   optlen);
1226		release_sock(sk);
1227		return err;
1228	}
1229	case IP_MULTICAST_ALL:
1230		val = inet->mc_all;
1231		break;
1232	case IP_PKTOPTIONS:
1233	{
1234		struct msghdr msg;
1235
1236		release_sock(sk);
1237
1238		if (sk->sk_type != SOCK_STREAM)
1239			return -ENOPROTOOPT;
1240
1241		msg.msg_control = optval;
1242		msg.msg_controllen = len;
1243		msg.msg_flags = flags;
1244
1245		if (inet->cmsg_flags & IP_CMSG_PKTINFO) {
1246			struct in_pktinfo info;
1247
1248			info.ipi_addr.s_addr = inet->inet_rcv_saddr;
1249			info.ipi_spec_dst.s_addr = inet->inet_rcv_saddr;
1250			info.ipi_ifindex = inet->mc_index;
1251			put_cmsg(&msg, SOL_IP, IP_PKTINFO, sizeof(info), &info);
1252		}
1253		if (inet->cmsg_flags & IP_CMSG_TTL) {
1254			int hlim = inet->mc_ttl;
1255			put_cmsg(&msg, SOL_IP, IP_TTL, sizeof(hlim), &hlim);
1256		}
 
 
 
 
1257		len -= msg.msg_controllen;
1258		return put_user(len, optlen);
1259	}
1260	case IP_FREEBIND:
1261		val = inet->freebind;
1262		break;
1263	case IP_TRANSPARENT:
1264		val = inet->transparent;
1265		break;
1266	case IP_MINTTL:
1267		val = inet->min_ttl;
1268		break;
1269	default:
1270		release_sock(sk);
1271		return -ENOPROTOOPT;
1272	}
1273	release_sock(sk);
1274
1275	if (len < sizeof(int) && len > 0 && val >= 0 && val <= 255) {
1276		unsigned char ucval = (unsigned char)val;
1277		len = 1;
1278		if (put_user(len, optlen))
1279			return -EFAULT;
1280		if (copy_to_user(optval, &ucval, 1))
1281			return -EFAULT;
1282	} else {
1283		len = min_t(unsigned int, sizeof(int), len);
1284		if (put_user(len, optlen))
1285			return -EFAULT;
1286		if (copy_to_user(optval, &val, len))
1287			return -EFAULT;
1288	}
1289	return 0;
 
 
 
 
 
 
1290}
1291
1292int ip_getsockopt(struct sock *sk, int level,
1293		  int optname, char __user *optval, int __user *optlen)
1294{
1295	int err;
1296
1297	err = do_ip_getsockopt(sk, level, optname, optval, optlen, 0);
 
 
 
 
 
1298#ifdef CONFIG_NETFILTER
1299	/* we need to exclude all possible ENOPROTOOPTs except default case */
1300	if (err == -ENOPROTOOPT && optname != IP_PKTOPTIONS &&
1301			!ip_mroute_opt(optname)) {
1302		int len;
1303
1304		if (get_user(len, optlen))
1305			return -EFAULT;
1306
1307		lock_sock(sk);
1308		err = nf_getsockopt(sk, PF_INET, optname, optval,
1309				&len);
1310		release_sock(sk);
1311		if (err >= 0)
1312			err = put_user(len, optlen);
1313		return err;
1314	}
1315#endif
1316	return err;
1317}
1318EXPORT_SYMBOL(ip_getsockopt);
1319
1320#ifdef CONFIG_COMPAT
1321int compat_ip_getsockopt(struct sock *sk, int level, int optname,
1322			 char __user *optval, int __user *optlen)
1323{
1324	int err;
1325
1326	if (optname == MCAST_MSFILTER)
1327		return compat_mc_getsockopt(sk, level, optname, optval, optlen,
1328			ip_getsockopt);
1329
1330	err = do_ip_getsockopt(sk, level, optname, optval, optlen,
1331		MSG_CMSG_COMPAT);
1332
 
 
 
 
 
1333#ifdef CONFIG_NETFILTER
1334	/* we need to exclude all possible ENOPROTOOPTs except default case */
1335	if (err == -ENOPROTOOPT && optname != IP_PKTOPTIONS &&
1336			!ip_mroute_opt(optname)) {
1337		int len;
1338
1339		if (get_user(len, optlen))
1340			return -EFAULT;
1341
1342		lock_sock(sk);
1343		err = compat_nf_getsockopt(sk, PF_INET, optname, optval, &len);
1344		release_sock(sk);
1345		if (err >= 0)
1346			err = put_user(len, optlen);
1347		return err;
1348	}
1349#endif
1350	return err;
1351}
1352EXPORT_SYMBOL(compat_ip_getsockopt);
1353#endif
v5.4
   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
  56static 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
  65static 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
  71static 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
  76static 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
  86static 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
 104static 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
 115static 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
 131static 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
 149static 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
 171void 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}
 240EXPORT_SYMBOL(ip_cmsg_recv_offset);
 241
 242int ip_cmsg_send(struct sock *sk, struct msghdr *msg, struct ipcm_cookie *ipc,
 243		 bool allow_ipv6)
 244{
 245	int err, val;
 246	struct cmsghdr *cmsg;
 247	struct net *net = sock_net(sk);
 248
 249	for_each_cmsghdr(cmsg, msg) {
 250		if (!CMSG_OK(msg, cmsg))
 251			return -EINVAL;
 252#if IS_ENABLED(CONFIG_IPV6)
 253		if (allow_ipv6 &&
 254		    cmsg->cmsg_level == SOL_IPV6 &&
 255		    cmsg->cmsg_type == IPV6_PKTINFO) {
 256			struct in6_pktinfo *src_info;
 257
 258			if (cmsg->cmsg_len < CMSG_LEN(sizeof(*src_info)))
 259				return -EINVAL;
 260			src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg);
 261			if (!ipv6_addr_v4mapped(&src_info->ipi6_addr))
 262				return -EINVAL;
 263			if (src_info->ipi6_ifindex)
 264				ipc->oif = src_info->ipi6_ifindex;
 265			ipc->addr = src_info->ipi6_addr.s6_addr32[3];
 266			continue;
 267		}
 268#endif
 269		if (cmsg->cmsg_level == SOL_SOCKET) {
 270			err = __sock_cmsg_send(sk, 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
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 327static 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
 335int 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
 392void 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
 421void 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 */
 461static 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 */
 472static 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 */
 500int 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);
 
 
 
 
 
 
 
 
 
 
 
 
 559out:
 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 */
 568static 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
 590static 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);
1137mc_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
1192e_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 */
1208void 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
1240int 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}
1264EXPORT_SYMBOL(ip_setsockopt);
1265
1266#ifdef CONFIG_COMPAT
1267int 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}
1291EXPORT_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
1299static 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
1309static 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
1549out:
1550	release_sock(sk);
1551	if (needs_rtnl)
1552		rtnl_unlock();
1553	return err;
1554}
1555
1556int 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}
1584EXPORT_SYMBOL(ip_getsockopt);
1585
1586#ifdef CONFIG_COMPAT
1587int 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}
1621EXPORT_SYMBOL(compat_ip_getsockopt);
1622#endif