1/*
   2 *	PF_INET6 socket protocol family
   3 *	Linux INET6 implementation
   4 *
   5 *	Authors:
   6 *	Pedro Roque		<roque@di.fc.ul.pt>
   7 *
   8 *	Adapted from linux/net/ipv4/af_inet.c
   9 *
  10 *	Fixes:
  11 *	piggy, Karl Knutson	:	Socket protocol table
  12 *	Hideaki YOSHIFUJI	:	sin6_scope_id support
  13 *	Arnaldo Melo		:	check proc_net_create return, cleanups
  14 *
  15 *	This program is free software; you can redistribute it and/or
  16 *	modify it under the terms of the GNU General Public License
  17 *	as published by the Free Software Foundation; either version
  18 *	2 of the License, or (at your option) any later version.
  19 */
  20
  21#define pr_fmt(fmt) "IPv6: " fmt
  22
  23#include <linux/module.h>
  24#include <linux/capability.h>
  25#include <linux/errno.h>
  26#include <linux/types.h>
  27#include <linux/socket.h>
  28#include <linux/in.h>
  29#include <linux/kernel.h>
  30#include <linux/timer.h>
  31#include <linux/string.h>
  32#include <linux/sockios.h>
  33#include <linux/net.h>
  34#include <linux/fcntl.h>
  35#include <linux/mm.h>
  36#include <linux/interrupt.h>
  37#include <linux/proc_fs.h>
  38#include <linux/stat.h>
  39#include <linux/init.h>
  40#include <linux/slab.h>
  41
  42#include <linux/inet.h>
  43#include <linux/netdevice.h>
  44#include <linux/icmpv6.h>
  45#include <linux/netfilter_ipv6.h>
  46
  47#include <net/ip.h>
  48#include <net/ipv6.h>
  49#include <net/udp.h>
  50#include <net/udplite.h>
  51#include <net/tcp.h>
  52#include <net/ping.h>
  53#include <net/protocol.h>
  54#include <net/inet_common.h>
  55#include <net/route.h>
  56#include <net/transp_v6.h>
  57#include <net/ip6_route.h>
  58#include <net/addrconf.h>
  59#include <net/ndisc.h>
  60#ifdef CONFIG_IPV6_TUNNEL
  61#include <net/ip6_tunnel.h>
  62#endif
  63#include <net/calipso.h>
  64#include <net/seg6.h>
  65
  66#include <linux/uaccess.h>
  67#include <linux/mroute6.h>
  68
  69#include "ip6_offload.h"
  70
  71MODULE_AUTHOR("Cast of dozens");
  72MODULE_DESCRIPTION("IPv6 protocol stack for Linux");
  73MODULE_LICENSE("GPL");
  74
  75/* The inetsw6 table contains everything that inet6_create needs to
  76 * build a new socket.
  77 */
  78static struct list_head inetsw6[SOCK_MAX];
  79static DEFINE_SPINLOCK(inetsw6_lock);
  80
  81struct ipv6_params ipv6_defaults = {
  82	.disable_ipv6 = 0,
  83	.autoconf = 1,
  84};
  85
  86static int disable_ipv6_mod;
  87
  88module_param_named(disable, disable_ipv6_mod, int, 0444);
  89MODULE_PARM_DESC(disable, "Disable IPv6 module such that it is non-functional");
  90
  91module_param_named(disable_ipv6, ipv6_defaults.disable_ipv6, int, 0444);
  92MODULE_PARM_DESC(disable_ipv6, "Disable IPv6 on all interfaces");
  93
  94module_param_named(autoconf, ipv6_defaults.autoconf, int, 0444);
  95MODULE_PARM_DESC(autoconf, "Enable IPv6 address autoconfiguration on all interfaces");
  96
  97bool ipv6_mod_enabled(void)
  98{
  99	return disable_ipv6_mod == 0;
 100}
 101EXPORT_SYMBOL_GPL(ipv6_mod_enabled);
 102
 103static __inline__ struct ipv6_pinfo *inet6_sk_generic(struct sock *sk)
 104{
 105	const int offset = sk->sk_prot->obj_size - sizeof(struct ipv6_pinfo);
 106
 107	return (struct ipv6_pinfo *)(((u8 *)sk) + offset);
 108}
 109
 110static int inet6_create(struct net *net, struct socket *sock, int protocol,
 111			int kern)
 112{
 113	struct inet_sock *inet;
 114	struct ipv6_pinfo *np;
 115	struct sock *sk;
 116	struct inet_protosw *answer;
 117	struct proto *answer_prot;
 118	unsigned char answer_flags;
 119	int try_loading_module = 0;
 120	int err;
 121
 122	if (protocol < 0 || protocol >= IPPROTO_MAX)
 123		return -EINVAL;
 124
 125	/* Look for the requested type/protocol pair. */
 126lookup_protocol:
 127	err = -ESOCKTNOSUPPORT;
 128	rcu_read_lock();
 129	list_for_each_entry_rcu(answer, &inetsw6[sock->type], list) {
 130
 131		err = 0;
 132		/* Check the non-wild match. */
 133		if (protocol == answer->protocol) {
 134			if (protocol != IPPROTO_IP)
 135				break;
 136		} else {
 137			/* Check for the two wild cases. */
 138			if (IPPROTO_IP == protocol) {
 139				protocol = answer->protocol;
 140				break;
 141			}
 142			if (IPPROTO_IP == answer->protocol)
 143				break;
 144		}
 145		err = -EPROTONOSUPPORT;
 146	}
 147
 148	if (err) {
 149		if (try_loading_module < 2) {
 150			rcu_read_unlock();
 151			/*
 152			 * Be more specific, e.g. net-pf-10-proto-132-type-1
 153			 * (net-pf-PF_INET6-proto-IPPROTO_SCTP-type-SOCK_STREAM)
 154			 */
 155			if (++try_loading_module == 1)
 156				request_module("net-pf-%d-proto-%d-type-%d",
 157						PF_INET6, protocol, sock->type);
 158			/*
 159			 * Fall back to generic, e.g. net-pf-10-proto-132
 160			 * (net-pf-PF_INET6-proto-IPPROTO_SCTP)
 161			 */
 162			else
 163				request_module("net-pf-%d-proto-%d",
 164						PF_INET6, protocol);
 165			goto lookup_protocol;
 166		} else
 167			goto out_rcu_unlock;
 168	}
 169
 170	err = -EPERM;
 171	if (sock->type == SOCK_RAW && !kern &&
 172	    !ns_capable(net->user_ns, CAP_NET_RAW))
 173		goto out_rcu_unlock;
 174
 175	sock->ops = answer->ops;
 176	answer_prot = answer->prot;
 177	answer_flags = answer->flags;
 178	rcu_read_unlock();
 179
 180	WARN_ON(!answer_prot->slab);
 181
 182	err = -ENOBUFS;
 183	sk = sk_alloc(net, PF_INET6, GFP_KERNEL, answer_prot, kern);
 184	if (!sk)
 185		goto out;
 186
 187	sock_init_data(sock, sk);
 188
 189	err = 0;
 190	if (INET_PROTOSW_REUSE & answer_flags)
 191		sk->sk_reuse = SK_CAN_REUSE;
 192
 193	inet = inet_sk(sk);
 194	inet->is_icsk = (INET_PROTOSW_ICSK & answer_flags) != 0;
 195
 196	if (SOCK_RAW == sock->type) {
 197		inet->inet_num = protocol;
 198		if (IPPROTO_RAW == protocol)
 199			inet->hdrincl = 1;
 200	}
 201
 202	sk->sk_destruct		= inet_sock_destruct;
 203	sk->sk_family		= PF_INET6;
 204	sk->sk_protocol		= protocol;
 205
 206	sk->sk_backlog_rcv	= answer->prot->backlog_rcv;
 207
 208	inet_sk(sk)->pinet6 = np = inet6_sk_generic(sk);
 209	np->hop_limit	= -1;
 210	np->mcast_hops	= IPV6_DEFAULT_MCASTHOPS;
 211	np->mc_loop	= 1;
 212	np->pmtudisc	= IPV6_PMTUDISC_WANT;
 213	np->repflow	= net->ipv6.sysctl.flowlabel_reflect;
 214	sk->sk_ipv6only	= net->ipv6.sysctl.bindv6only;
 215
 216	/* Init the ipv4 part of the socket since we can have sockets
 217	 * using v6 API for ipv4.
 218	 */
 219	inet->uc_ttl	= -1;
 220
 221	inet->mc_loop	= 1;
 222	inet->mc_ttl	= 1;
 223	inet->mc_index	= 0;
 224	inet->mc_list	= NULL;
 225	inet->rcv_tos	= 0;
 226
 227	if (net->ipv4.sysctl_ip_no_pmtu_disc)
 228		inet->pmtudisc = IP_PMTUDISC_DONT;
 229	else
 230		inet->pmtudisc = IP_PMTUDISC_WANT;
 231	/*
 232	 * Increment only the relevant sk_prot->socks debug field, this changes
 233	 * the previous behaviour of incrementing both the equivalent to
 234	 * answer->prot->socks (inet6_sock_nr) and inet_sock_nr.
 235	 *
 236	 * This allows better debug granularity as we'll know exactly how many
 237	 * UDPv6, TCPv6, etc socks were allocated, not the sum of all IPv6
 238	 * transport protocol socks. -acme
 239	 */
 240	sk_refcnt_debug_inc(sk);
 241
 242	if (inet->inet_num) {
 243		/* It assumes that any protocol which allows
 244		 * the user to assign a number at socket
 245		 * creation time automatically shares.
 246		 */
 247		inet->inet_sport = htons(inet->inet_num);
 248		err = sk->sk_prot->hash(sk);
 249		if (err) {
 250			sk_common_release(sk);
 251			goto out;
 252		}
 253	}
 254	if (sk->sk_prot->init) {
 255		err = sk->sk_prot->init(sk);
 256		if (err) {
 257			sk_common_release(sk);
 258			goto out;
 259		}
 260	}
 261
 262	if (!kern) {
 263		err = BPF_CGROUP_RUN_PROG_INET_SOCK(sk);
 264		if (err) {
 265			sk_common_release(sk);
 266			goto out;
 267		}
 268	}
 269out:
 270	return err;
 271out_rcu_unlock:
 272	rcu_read_unlock();
 273	goto out;
 274}
 275
 276
 277/* bind for INET6 API */
 278int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 279{
 
 280	struct sock *sk = sock->sk;
 
 
 
 
 
 
 281	int err = 0;
 282
 283	/* If the socket has its own bind function then use it. */
 284	if (sk->sk_prot->bind)
 285		return sk->sk_prot->bind(sk, uaddr, addr_len);
 286
 287	if (addr_len < SIN6_LEN_RFC2133)
 288		return -EINVAL;
 289
 290	/* BPF prog is run before any checks are done so that if the prog
 291	 * changes context in a wrong way it will be caught.
 292	 */
 293	err = BPF_CGROUP_RUN_PROG_INET6_BIND(sk, uaddr);
 294	if (err)
 295		return err;
 296
 297	return __inet6_bind(sk, uaddr, addr_len, false, true);
 298}
 299EXPORT_SYMBOL(inet6_bind);
 300
 301int __inet6_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len,
 302		 bool force_bind_address_no_port, bool with_lock)
 303{
 304	struct sockaddr_in6 *addr = (struct sockaddr_in6 *)uaddr;
 305	struct inet_sock *inet = inet_sk(sk);
 306	struct ipv6_pinfo *np = inet6_sk(sk);
 307	struct net *net = sock_net(sk);
 308	__be32 v4addr = 0;
 309	unsigned short snum;
 310	bool saved_ipv6only;
 311	int addr_type = 0;
 312	int err = 0;
 313
 314	if (addr->sin6_family != AF_INET6)
 315		return -EAFNOSUPPORT;
 316
 317	addr_type = ipv6_addr_type(&addr->sin6_addr);
 318	if ((addr_type & IPV6_ADDR_MULTICAST) && sk->sk_type == SOCK_STREAM)
 319		return -EINVAL;
 320
 321	snum = ntohs(addr->sin6_port);
 322	if (snum && snum < inet_prot_sock(net) &&
 323	    !ns_capable(net->user_ns, CAP_NET_BIND_SERVICE))
 324		return -EACCES;
 325
 326	if (with_lock)
 327		lock_sock(sk);
 328
 329	/* Check these errors (active socket, double bind). */
 330	if (sk->sk_state != TCP_CLOSE || inet->inet_num) {
 331		err = -EINVAL;
 332		goto out;
 333	}
 334
 335	/* Check if the address belongs to the host. */
 336	if (addr_type == IPV6_ADDR_MAPPED) {
 337		int chk_addr_ret;
 338
 339		/* Binding to v4-mapped address on a v6-only socket
 340		 * makes no sense
 341		 */
 342		if (sk->sk_ipv6only) {
 343			err = -EINVAL;
 344			goto out;
 345		}
 346
 347		/* Reproduce AF_INET checks to make the bindings consistent */
 348		v4addr = addr->sin6_addr.s6_addr32[3];
 349		chk_addr_ret = inet_addr_type(net, v4addr);
 350		if (!net->ipv4.sysctl_ip_nonlocal_bind &&
 351		    !(inet->freebind || inet->transparent) &&
 352		    v4addr != htonl(INADDR_ANY) &&
 353		    chk_addr_ret != RTN_LOCAL &&
 354		    chk_addr_ret != RTN_MULTICAST &&
 355		    chk_addr_ret != RTN_BROADCAST) {
 356			err = -EADDRNOTAVAIL;
 357			goto out;
 358		}
 359	} else {
 360		if (addr_type != IPV6_ADDR_ANY) {
 361			struct net_device *dev = NULL;
 362
 363			rcu_read_lock();
 364			if (__ipv6_addr_needs_scope_id(addr_type)) {
 365				if (addr_len >= sizeof(struct sockaddr_in6) &&
 366				    addr->sin6_scope_id) {
 367					/* Override any existing binding, if another one
 368					 * is supplied by user.
 369					 */
 370					sk->sk_bound_dev_if = addr->sin6_scope_id;
 371				}
 372
 373				/* Binding to link-local address requires an interface */
 374				if (!sk->sk_bound_dev_if) {
 375					err = -EINVAL;
 376					goto out_unlock;
 377				}
 378				dev = dev_get_by_index_rcu(net, sk->sk_bound_dev_if);
 379				if (!dev) {
 380					err = -ENODEV;
 381					goto out_unlock;
 382				}
 383			}
 384
 385			/* ipv4 addr of the socket is invalid.  Only the
 386			 * unspecified and mapped address have a v4 equivalent.
 387			 */
 388			v4addr = LOOPBACK4_IPV6;
 389			if (!(addr_type & IPV6_ADDR_MULTICAST))	{
 390				if (!net->ipv6.sysctl.ip_nonlocal_bind &&
 391				    !(inet->freebind || inet->transparent) &&
 392				    !ipv6_chk_addr(net, &addr->sin6_addr,
 393						   dev, 0)) {
 394					err = -EADDRNOTAVAIL;
 395					goto out_unlock;
 396				}
 397			}
 398			rcu_read_unlock();
 399		}
 400	}
 401
 402	inet->inet_rcv_saddr = v4addr;
 403	inet->inet_saddr = v4addr;
 404
 405	sk->sk_v6_rcv_saddr = addr->sin6_addr;
 406
 407	if (!(addr_type & IPV6_ADDR_MULTICAST))
 408		np->saddr = addr->sin6_addr;
 409
 410	saved_ipv6only = sk->sk_ipv6only;
 411	if (addr_type != IPV6_ADDR_ANY && addr_type != IPV6_ADDR_MAPPED)
 412		sk->sk_ipv6only = 1;
 413
 414	/* Make sure we are allowed to bind here. */
 415	if (snum || !(inet->bind_address_no_port ||
 416		      force_bind_address_no_port)) {
 417		if (sk->sk_prot->get_port(sk, snum)) {
 418			sk->sk_ipv6only = saved_ipv6only;
 419			inet_reset_saddr(sk);
 420			err = -EADDRINUSE;
 421			goto out;
 422		}
 423		err = BPF_CGROUP_RUN_PROG_INET6_POST_BIND(sk);
 424		if (err) {
 425			sk->sk_ipv6only = saved_ipv6only;
 426			inet_reset_saddr(sk);
 427			goto out;
 428		}
 429	}
 430
 431	if (addr_type != IPV6_ADDR_ANY)
 432		sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
 
 
 
 433	if (snum)
 434		sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
 435	inet->inet_sport = htons(inet->inet_num);
 436	inet->inet_dport = 0;
 437	inet->inet_daddr = 0;
 438out:
 439	if (with_lock)
 440		release_sock(sk);
 441	return err;
 442out_unlock:
 443	rcu_read_unlock();
 444	goto out;
 445}
 
 446
 447int inet6_release(struct socket *sock)
 448{
 449	struct sock *sk = sock->sk;
 450
 451	if (!sk)
 452		return -EINVAL;
 453
 454	/* Free mc lists */
 455	ipv6_sock_mc_close(sk);
 456
 457	/* Free ac lists */
 458	ipv6_sock_ac_close(sk);
 459
 460	return inet_release(sock);
 461}
 462EXPORT_SYMBOL(inet6_release);
 463
 464void inet6_destroy_sock(struct sock *sk)
 465{
 466	struct ipv6_pinfo *np = inet6_sk(sk);
 467	struct sk_buff *skb;
 468	struct ipv6_txoptions *opt;
 469
 470	/* Release rx options */
 471
 472	skb = xchg(&np->pktoptions, NULL);
 473	if (skb)
 474		kfree_skb(skb);
 475
 476	skb = xchg(&np->rxpmtu, NULL);
 477	if (skb)
 478		kfree_skb(skb);
 479
 480	/* Free flowlabels */
 481	fl6_free_socklist(sk);
 482
 483	/* Free tx options */
 484
 485	opt = xchg((__force struct ipv6_txoptions **)&np->opt, NULL);
 486	if (opt) {
 487		atomic_sub(opt->tot_len, &sk->sk_omem_alloc);
 488		txopt_put(opt);
 489	}
 490}
 491EXPORT_SYMBOL_GPL(inet6_destroy_sock);
 492
 493/*
 494 *	This does both peername and sockname.
 495 */
 496
 497int inet6_getname(struct socket *sock, struct sockaddr *uaddr,
 498		 int peer)
 499{
 500	struct sockaddr_in6 *sin = (struct sockaddr_in6 *)uaddr;
 501	struct sock *sk = sock->sk;
 502	struct inet_sock *inet = inet_sk(sk);
 503	struct ipv6_pinfo *np = inet6_sk(sk);
 504
 505	sin->sin6_family = AF_INET6;
 506	sin->sin6_flowinfo = 0;
 507	sin->sin6_scope_id = 0;
 508	if (peer) {
 509		if (!inet->inet_dport)
 510			return -ENOTCONN;
 511		if (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
 512		    peer == 1)
 513			return -ENOTCONN;
 514		sin->sin6_port = inet->inet_dport;
 515		sin->sin6_addr = sk->sk_v6_daddr;
 516		if (np->sndflow)
 517			sin->sin6_flowinfo = np->flow_label;
 518	} else {
 519		if (ipv6_addr_any(&sk->sk_v6_rcv_saddr))
 520			sin->sin6_addr = np->saddr;
 521		else
 522			sin->sin6_addr = sk->sk_v6_rcv_saddr;
 523
 524		sin->sin6_port = inet->inet_sport;
 525	}
 526	sin->sin6_scope_id = ipv6_iface_scope_id(&sin->sin6_addr,
 527						 sk->sk_bound_dev_if);
 528	return sizeof(*sin);
 
 529}
 530EXPORT_SYMBOL(inet6_getname);
 531
 532int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
 533{
 534	struct sock *sk = sock->sk;
 535	struct net *net = sock_net(sk);
 536
 537	switch (cmd) {
 538	case SIOCGSTAMP:
 539		return sock_get_timestamp(sk, (struct timeval __user *)arg);
 540
 541	case SIOCGSTAMPNS:
 542		return sock_get_timestampns(sk, (struct timespec __user *)arg);
 543
 544	case SIOCADDRT:
 545	case SIOCDELRT:
 546
 547		return ipv6_route_ioctl(net, cmd, (void __user *)arg);
 548
 549	case SIOCSIFADDR:
 550		return addrconf_add_ifaddr(net, (void __user *) arg);
 551	case SIOCDIFADDR:
 552		return addrconf_del_ifaddr(net, (void __user *) arg);
 553	case SIOCSIFDSTADDR:
 554		return addrconf_set_dstaddr(net, (void __user *) arg);
 555	default:
 556		if (!sk->sk_prot->ioctl)
 557			return -ENOIOCTLCMD;
 558		return sk->sk_prot->ioctl(sk, cmd, arg);
 559	}
 560	/*NOTREACHED*/
 561	return 0;
 562}
 563EXPORT_SYMBOL(inet6_ioctl);
 564
 565const struct proto_ops inet6_stream_ops = {
 566	.family		   = PF_INET6,
 567	.owner		   = THIS_MODULE,
 568	.release	   = inet6_release,
 569	.bind		   = inet6_bind,
 570	.connect	   = inet_stream_connect,	/* ok		*/
 571	.socketpair	   = sock_no_socketpair,	/* a do nothing	*/
 572	.accept		   = inet_accept,		/* ok		*/
 573	.getname	   = inet6_getname,
 574	.poll		   = tcp_poll,			/* ok		*/
 575	.ioctl		   = inet6_ioctl,		/* must change  */
 576	.listen		   = inet_listen,		/* ok		*/
 577	.shutdown	   = inet_shutdown,		/* ok		*/
 578	.setsockopt	   = sock_common_setsockopt,	/* ok		*/
 579	.getsockopt	   = sock_common_getsockopt,	/* ok		*/
 580	.sendmsg	   = inet_sendmsg,		/* ok		*/
 581	.recvmsg	   = inet_recvmsg,		/* ok		*/
 582	.mmap		   = sock_no_mmap,
 583	.sendpage	   = inet_sendpage,
 584	.sendmsg_locked    = tcp_sendmsg_locked,
 585	.sendpage_locked   = tcp_sendpage_locked,
 586	.splice_read	   = tcp_splice_read,
 587	.read_sock	   = tcp_read_sock,
 588	.peek_len	   = tcp_peek_len,
 589#ifdef CONFIG_COMPAT
 590	.compat_setsockopt = compat_sock_common_setsockopt,
 591	.compat_getsockopt = compat_sock_common_getsockopt,
 592#endif
 593};
 594
 595const struct proto_ops inet6_dgram_ops = {
 596	.family		   = PF_INET6,
 597	.owner		   = THIS_MODULE,
 598	.release	   = inet6_release,
 599	.bind		   = inet6_bind,
 600	.connect	   = inet_dgram_connect,	/* ok		*/
 601	.socketpair	   = sock_no_socketpair,	/* a do nothing	*/
 602	.accept		   = sock_no_accept,		/* a do nothing	*/
 603	.getname	   = inet6_getname,
 604	.poll		   = udp_poll,			/* ok		*/
 605	.ioctl		   = inet6_ioctl,		/* must change  */
 606	.listen		   = sock_no_listen,		/* ok		*/
 607	.shutdown	   = inet_shutdown,		/* ok		*/
 608	.setsockopt	   = sock_common_setsockopt,	/* ok		*/
 609	.getsockopt	   = sock_common_getsockopt,	/* ok		*/
 610	.sendmsg	   = inet_sendmsg,		/* ok		*/
 611	.recvmsg	   = inet_recvmsg,		/* ok		*/
 612	.mmap		   = sock_no_mmap,
 613	.sendpage	   = sock_no_sendpage,
 614	.set_peek_off	   = sk_set_peek_off,
 615#ifdef CONFIG_COMPAT
 616	.compat_setsockopt = compat_sock_common_setsockopt,
 617	.compat_getsockopt = compat_sock_common_getsockopt,
 618#endif
 619};
 620
 621static const struct net_proto_family inet6_family_ops = {
 622	.family = PF_INET6,
 623	.create = inet6_create,
 624	.owner	= THIS_MODULE,
 625};
 626
 627int inet6_register_protosw(struct inet_protosw *p)
 628{
 629	struct list_head *lh;
 630	struct inet_protosw *answer;
 631	struct list_head *last_perm;
 632	int protocol = p->protocol;
 633	int ret;
 634
 635	spin_lock_bh(&inetsw6_lock);
 636
 637	ret = -EINVAL;
 638	if (p->type >= SOCK_MAX)
 639		goto out_illegal;
 640
 641	/* If we are trying to override a permanent protocol, bail. */
 642	answer = NULL;
 643	ret = -EPERM;
 644	last_perm = &inetsw6[p->type];
 645	list_for_each(lh, &inetsw6[p->type]) {
 646		answer = list_entry(lh, struct inet_protosw, list);
 647
 648		/* Check only the non-wild match. */
 649		if (INET_PROTOSW_PERMANENT & answer->flags) {
 650			if (protocol == answer->protocol)
 651				break;
 652			last_perm = lh;
 653		}
 654
 655		answer = NULL;
 656	}
 657	if (answer)
 658		goto out_permanent;
 659
 660	/* Add the new entry after the last permanent entry if any, so that
 661	 * the new entry does not override a permanent entry when matched with
 662	 * a wild-card protocol. But it is allowed to override any existing
 663	 * non-permanent entry.  This means that when we remove this entry, the
 664	 * system automatically returns to the old behavior.
 665	 */
 666	list_add_rcu(&p->list, last_perm);
 667	ret = 0;
 668out:
 669	spin_unlock_bh(&inetsw6_lock);
 670	return ret;
 671
 672out_permanent:
 673	pr_err("Attempt to override permanent protocol %d\n", protocol);
 674	goto out;
 675
 676out_illegal:
 677	pr_err("Ignoring attempt to register invalid socket type %d\n",
 678	       p->type);
 679	goto out;
 680}
 681EXPORT_SYMBOL(inet6_register_protosw);
 682
 683void
 684inet6_unregister_protosw(struct inet_protosw *p)
 685{
 686	if (INET_PROTOSW_PERMANENT & p->flags) {
 687		pr_err("Attempt to unregister permanent protocol %d\n",
 688		       p->protocol);
 689	} else {
 690		spin_lock_bh(&inetsw6_lock);
 691		list_del_rcu(&p->list);
 692		spin_unlock_bh(&inetsw6_lock);
 693
 694		synchronize_net();
 695	}
 696}
 697EXPORT_SYMBOL(inet6_unregister_protosw);
 698
 699int inet6_sk_rebuild_header(struct sock *sk)
 700{
 701	struct ipv6_pinfo *np = inet6_sk(sk);
 702	struct dst_entry *dst;
 703
 704	dst = __sk_dst_check(sk, np->dst_cookie);
 705
 706	if (!dst) {
 707		struct inet_sock *inet = inet_sk(sk);
 708		struct in6_addr *final_p, final;
 709		struct flowi6 fl6;
 710
 711		memset(&fl6, 0, sizeof(fl6));
 712		fl6.flowi6_proto = sk->sk_protocol;
 713		fl6.daddr = sk->sk_v6_daddr;
 714		fl6.saddr = np->saddr;
 715		fl6.flowlabel = np->flow_label;
 716		fl6.flowi6_oif = sk->sk_bound_dev_if;
 717		fl6.flowi6_mark = sk->sk_mark;
 718		fl6.fl6_dport = inet->inet_dport;
 719		fl6.fl6_sport = inet->inet_sport;
 720		fl6.flowi6_uid = sk->sk_uid;
 721		security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
 722
 723		rcu_read_lock();
 724		final_p = fl6_update_dst(&fl6, rcu_dereference(np->opt),
 725					 &final);
 726		rcu_read_unlock();
 727
 728		dst = ip6_dst_lookup_flow(sk, &fl6, final_p);
 729		if (IS_ERR(dst)) {
 730			sk->sk_route_caps = 0;
 731			sk->sk_err_soft = -PTR_ERR(dst);
 732			return PTR_ERR(dst);
 733		}
 734
 735		ip6_dst_store(sk, dst, NULL, NULL);
 736	}
 737
 738	return 0;
 739}
 740EXPORT_SYMBOL_GPL(inet6_sk_rebuild_header);
 741
 742bool ipv6_opt_accepted(const struct sock *sk, const struct sk_buff *skb,
 743		       const struct inet6_skb_parm *opt)
 744{
 745	const struct ipv6_pinfo *np = inet6_sk(sk);
 746
 747	if (np->rxopt.all) {
 748		if (((opt->flags & IP6SKB_HOPBYHOP) &&
 749		     (np->rxopt.bits.hopopts || np->rxopt.bits.ohopopts)) ||
 750		    (ip6_flowinfo((struct ipv6hdr *) skb_network_header(skb)) &&
 751		     np->rxopt.bits.rxflow) ||
 752		    (opt->srcrt && (np->rxopt.bits.srcrt ||
 753		     np->rxopt.bits.osrcrt)) ||
 754		    ((opt->dst1 || opt->dst0) &&
 755		     (np->rxopt.bits.dstopts || np->rxopt.bits.odstopts)))
 756			return true;
 757	}
 758	return false;
 759}
 760EXPORT_SYMBOL_GPL(ipv6_opt_accepted);
 761
 762static struct packet_type ipv6_packet_type __read_mostly = {
 763	.type = cpu_to_be16(ETH_P_IPV6),
 764	.func = ipv6_rcv,
 765};
 766
 767static int __init ipv6_packet_init(void)
 768{
 769	dev_add_pack(&ipv6_packet_type);
 770	return 0;
 771}
 772
 773static void ipv6_packet_cleanup(void)
 774{
 775	dev_remove_pack(&ipv6_packet_type);
 776}
 777
 778static int __net_init ipv6_init_mibs(struct net *net)
 779{
 780	int i;
 781
 782	net->mib.udp_stats_in6 = alloc_percpu(struct udp_mib);
 783	if (!net->mib.udp_stats_in6)
 784		return -ENOMEM;
 785	net->mib.udplite_stats_in6 = alloc_percpu(struct udp_mib);
 786	if (!net->mib.udplite_stats_in6)
 787		goto err_udplite_mib;
 788	net->mib.ipv6_statistics = alloc_percpu(struct ipstats_mib);
 789	if (!net->mib.ipv6_statistics)
 790		goto err_ip_mib;
 791
 792	for_each_possible_cpu(i) {
 793		struct ipstats_mib *af_inet6_stats;
 794		af_inet6_stats = per_cpu_ptr(net->mib.ipv6_statistics, i);
 795		u64_stats_init(&af_inet6_stats->syncp);
 796	}
 797
 798
 799	net->mib.icmpv6_statistics = alloc_percpu(struct icmpv6_mib);
 800	if (!net->mib.icmpv6_statistics)
 801		goto err_icmp_mib;
 802	net->mib.icmpv6msg_statistics = kzalloc(sizeof(struct icmpv6msg_mib),
 803						GFP_KERNEL);
 804	if (!net->mib.icmpv6msg_statistics)
 805		goto err_icmpmsg_mib;
 806	return 0;
 807
 808err_icmpmsg_mib:
 809	free_percpu(net->mib.icmpv6_statistics);
 810err_icmp_mib:
 811	free_percpu(net->mib.ipv6_statistics);
 812err_ip_mib:
 813	free_percpu(net->mib.udplite_stats_in6);
 814err_udplite_mib:
 815	free_percpu(net->mib.udp_stats_in6);
 816	return -ENOMEM;
 817}
 818
 819static void ipv6_cleanup_mibs(struct net *net)
 820{
 821	free_percpu(net->mib.udp_stats_in6);
 822	free_percpu(net->mib.udplite_stats_in6);
 823	free_percpu(net->mib.ipv6_statistics);
 824	free_percpu(net->mib.icmpv6_statistics);
 825	kfree(net->mib.icmpv6msg_statistics);
 826}
 827
 828static int __net_init inet6_net_init(struct net *net)
 829{
 830	int err = 0;
 831
 832	net->ipv6.sysctl.bindv6only = 0;
 833	net->ipv6.sysctl.icmpv6_time = 1*HZ;
 834	net->ipv6.sysctl.flowlabel_consistency = 1;
 835	net->ipv6.sysctl.auto_flowlabels = IP6_DEFAULT_AUTO_FLOW_LABELS;
 836	net->ipv6.sysctl.idgen_retries = 3;
 837	net->ipv6.sysctl.idgen_delay = 1 * HZ;
 838	net->ipv6.sysctl.flowlabel_state_ranges = 0;
 839	net->ipv6.sysctl.max_dst_opts_cnt = IP6_DEFAULT_MAX_DST_OPTS_CNT;
 840	net->ipv6.sysctl.max_hbh_opts_cnt = IP6_DEFAULT_MAX_HBH_OPTS_CNT;
 841	net->ipv6.sysctl.max_dst_opts_len = IP6_DEFAULT_MAX_DST_OPTS_LEN;
 842	net->ipv6.sysctl.max_hbh_opts_len = IP6_DEFAULT_MAX_HBH_OPTS_LEN;
 843	atomic_set(&net->ipv6.fib6_sernum, 1);
 844
 845	err = ipv6_init_mibs(net);
 846	if (err)
 847		return err;
 848#ifdef CONFIG_PROC_FS
 849	err = udp6_proc_init(net);
 850	if (err)
 851		goto out;
 852	err = tcp6_proc_init(net);
 853	if (err)
 854		goto proc_tcp6_fail;
 855	err = ac6_proc_init(net);
 856	if (err)
 857		goto proc_ac6_fail;
 858#endif
 859	return err;
 860
 861#ifdef CONFIG_PROC_FS
 862proc_ac6_fail:
 863	tcp6_proc_exit(net);
 864proc_tcp6_fail:
 865	udp6_proc_exit(net);
 866out:
 867	ipv6_cleanup_mibs(net);
 868	return err;
 869#endif
 870}
 871
 872static void __net_exit inet6_net_exit(struct net *net)
 873{
 874#ifdef CONFIG_PROC_FS
 875	udp6_proc_exit(net);
 876	tcp6_proc_exit(net);
 877	ac6_proc_exit(net);
 878#endif
 879	ipv6_cleanup_mibs(net);
 880}
 881
 882static struct pernet_operations inet6_net_ops = {
 883	.init = inet6_net_init,
 884	.exit = inet6_net_exit,
 885};
 886
 887static const struct ipv6_stub ipv6_stub_impl = {
 888	.ipv6_sock_mc_join = ipv6_sock_mc_join,
 889	.ipv6_sock_mc_drop = ipv6_sock_mc_drop,
 890	.ipv6_dst_lookup = ip6_dst_lookup,
 891	.udpv6_encap_enable = udpv6_encap_enable,
 892	.ndisc_send_na = ndisc_send_na,
 893	.nd_tbl	= &nd_tbl,
 894};
 895
 896static const struct ipv6_bpf_stub ipv6_bpf_stub_impl = {
 897	.inet6_bind = __inet6_bind,
 898};
 899
 900static int __init inet6_init(void)
 901{
 902	struct list_head *r;
 903	int err = 0;
 904
 905	sock_skb_cb_check_size(sizeof(struct inet6_skb_parm));
 906
 907	/* Register the socket-side information for inet6_create.  */
 908	for (r = &inetsw6[0]; r < &inetsw6[SOCK_MAX]; ++r)
 909		INIT_LIST_HEAD(r);
 910
 911	if (disable_ipv6_mod) {
 912		pr_info("Loaded, but administratively disabled, reboot required to enable\n");
 913		goto out;
 914	}
 915
 916	err = proto_register(&tcpv6_prot, 1);
 917	if (err)
 918		goto out;
 919
 920	err = proto_register(&udpv6_prot, 1);
 921	if (err)
 922		goto out_unregister_tcp_proto;
 923
 924	err = proto_register(&udplitev6_prot, 1);
 925	if (err)
 926		goto out_unregister_udp_proto;
 927
 928	err = proto_register(&rawv6_prot, 1);
 929	if (err)
 930		goto out_unregister_udplite_proto;
 931
 932	err = proto_register(&pingv6_prot, 1);
 933	if (err)
 934		goto out_unregister_ping_proto;
 935
 936	/* We MUST register RAW sockets before we create the ICMP6,
 937	 * IGMP6, or NDISC control sockets.
 938	 */
 939	err = rawv6_init();
 940	if (err)
 941		goto out_unregister_raw_proto;
 942
 943	/* Register the family here so that the init calls below will
 944	 * be able to create sockets. (?? is this dangerous ??)
 945	 */
 946	err = sock_register(&inet6_family_ops);
 947	if (err)
 948		goto out_sock_register_fail;
 949
 950	/*
 951	 *	ipngwg API draft makes clear that the correct semantics
 952	 *	for TCP and UDP is to consider one TCP and UDP instance
 953	 *	in a host available by both INET and INET6 APIs and
 954	 *	able to communicate via both network protocols.
 955	 */
 956
 957	err = register_pernet_subsys(&inet6_net_ops);
 958	if (err)
 959		goto register_pernet_fail;
 960	err = ip6_mr_init();
 961	if (err)
 962		goto ipmr_fail;
 963	err = icmpv6_init();
 964	if (err)
 965		goto icmp_fail;
 
 
 
 966	err = ndisc_init();
 967	if (err)
 968		goto ndisc_fail;
 969	err = igmp6_init();
 970	if (err)
 971		goto igmp_fail;
 972
 
 
 973	err = ipv6_netfilter_init();
 974	if (err)
 975		goto netfilter_fail;
 976	/* Create /proc/foo6 entries. */
 977#ifdef CONFIG_PROC_FS
 978	err = -ENOMEM;
 979	if (raw6_proc_init())
 980		goto proc_raw6_fail;
 981	if (udplite6_proc_init())
 982		goto proc_udplite6_fail;
 983	if (ipv6_misc_proc_init())
 984		goto proc_misc6_fail;
 985	if (if6_proc_init())
 986		goto proc_if6_fail;
 987#endif
 988	err = ip6_route_init();
 989	if (err)
 990		goto ip6_route_fail;
 991	err = ndisc_late_init();
 992	if (err)
 993		goto ndisc_late_fail;
 994	err = ip6_flowlabel_init();
 995	if (err)
 996		goto ip6_flowlabel_fail;
 997	err = addrconf_init();
 998	if (err)
 999		goto addrconf_fail;
1000
1001	/* Init v6 extension headers. */
1002	err = ipv6_exthdrs_init();
1003	if (err)
1004		goto ipv6_exthdrs_fail;
1005
1006	err = ipv6_frag_init();
1007	if (err)
1008		goto ipv6_frag_fail;
1009
1010	/* Init v6 transport protocols. */
1011	err = udpv6_init();
1012	if (err)
1013		goto udpv6_fail;
1014
1015	err = udplitev6_init();
1016	if (err)
1017		goto udplitev6_fail;
1018
1019	err = udpv6_offload_init();
1020	if (err)
1021		goto udpv6_offload_fail;
1022
1023	err = tcpv6_init();
1024	if (err)
1025		goto tcpv6_fail;
1026
1027	err = ipv6_packet_init();
1028	if (err)
1029		goto ipv6_packet_fail;
1030
1031	err = pingv6_init();
1032	if (err)
1033		goto pingv6_fail;
1034
1035	err = calipso_init();
1036	if (err)
1037		goto calipso_fail;
1038
1039	err = seg6_init();
1040	if (err)
1041		goto seg6_fail;
1042
1043	err = igmp6_late_init();
1044	if (err)
1045		goto igmp6_late_err;
1046
1047#ifdef CONFIG_SYSCTL
1048	err = ipv6_sysctl_register();
1049	if (err)
1050		goto sysctl_fail;
1051#endif
1052
1053	/* ensure that ipv6 stubs are visible only after ipv6 is ready */
1054	wmb();
1055	ipv6_stub = &ipv6_stub_impl;
1056	ipv6_bpf_stub = &ipv6_bpf_stub_impl;
1057out:
1058	return err;
1059
1060#ifdef CONFIG_SYSCTL
1061sysctl_fail:
1062	igmp6_late_cleanup();
1063#endif
1064igmp6_late_err:
1065	seg6_exit();
 
1066seg6_fail:
1067	calipso_exit();
1068calipso_fail:
1069	pingv6_exit();
1070pingv6_fail:
1071	ipv6_packet_cleanup();
1072ipv6_packet_fail:
1073	tcpv6_exit();
1074tcpv6_fail:
1075	udpv6_offload_exit();
1076udpv6_offload_fail:
1077	udplitev6_exit();
1078udplitev6_fail:
1079	udpv6_exit();
1080udpv6_fail:
1081	ipv6_frag_exit();
1082ipv6_frag_fail:
1083	ipv6_exthdrs_exit();
1084ipv6_exthdrs_fail:
1085	addrconf_cleanup();
1086addrconf_fail:
1087	ip6_flowlabel_cleanup();
1088ip6_flowlabel_fail:
1089	ndisc_late_cleanup();
1090ndisc_late_fail:
1091	ip6_route_cleanup();
1092ip6_route_fail:
1093#ifdef CONFIG_PROC_FS
1094	if6_proc_exit();
1095proc_if6_fail:
1096	ipv6_misc_proc_exit();
1097proc_misc6_fail:
1098	udplite6_proc_exit();
1099proc_udplite6_fail:
1100	raw6_proc_exit();
1101proc_raw6_fail:
1102#endif
1103	ipv6_netfilter_fini();
1104netfilter_fail:
1105	igmp6_cleanup();
1106igmp_fail:
1107	ndisc_cleanup();
1108ndisc_fail:
1109	ip6_mr_cleanup();
1110icmp_fail:
1111	unregister_pernet_subsys(&inet6_net_ops);
1112ipmr_fail:
1113	icmpv6_cleanup();
 
 
1114register_pernet_fail:
1115	sock_unregister(PF_INET6);
1116	rtnl_unregister_all(PF_INET6);
1117out_sock_register_fail:
1118	rawv6_exit();
1119out_unregister_ping_proto:
1120	proto_unregister(&pingv6_prot);
1121out_unregister_raw_proto:
1122	proto_unregister(&rawv6_prot);
1123out_unregister_udplite_proto:
1124	proto_unregister(&udplitev6_prot);
1125out_unregister_udp_proto:
1126	proto_unregister(&udpv6_prot);
1127out_unregister_tcp_proto:
1128	proto_unregister(&tcpv6_prot);
1129	goto out;
1130}
1131module_init(inet6_init);
1132
1133MODULE_ALIAS_NETPROTO(PF_INET6);