1/*
   2 *	NET3	IP device support routines.
   3 *
   4 *		This program is free software; you can redistribute it and/or
   5 *		modify it under the terms of the GNU General Public License
   6 *		as published by the Free Software Foundation; either version
   7 *		2 of the License, or (at your option) any later version.
   8 *
   9 *	Derived from the IP parts of dev.c 1.0.19
  10 * 		Authors:	Ross Biro
  11 *				Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
  12 *				Mark Evans, <evansmp@uhura.aston.ac.uk>
  13 *
  14 *	Additional Authors:
  15 *		Alan Cox, <gw4pts@gw4pts.ampr.org>
  16 *		Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
  17 *
  18 *	Changes:
  19 *		Alexey Kuznetsov:	pa_* fields are replaced with ifaddr
  20 *					lists.
  21 *		Cyrus Durgin:		updated for kmod
  22 *		Matthias Andree:	in devinet_ioctl, compare label and
  23 *					address (4.4BSD alias style support),
  24 *					fall back to comparing just the label
  25 *					if no match found.
  26 */
  27
  28
  29#include <asm/uaccess.h>
  30#include <linux/bitops.h>
  31#include <linux/capability.h>
  32#include <linux/module.h>
  33#include <linux/types.h>
  34#include <linux/kernel.h>
  35#include <linux/string.h>
  36#include <linux/mm.h>
  37#include <linux/socket.h>
  38#include <linux/sockios.h>
  39#include <linux/in.h>
  40#include <linux/errno.h>
  41#include <linux/interrupt.h>
  42#include <linux/if_addr.h>
  43#include <linux/if_ether.h>
  44#include <linux/inet.h>
  45#include <linux/netdevice.h>
  46#include <linux/etherdevice.h>
  47#include <linux/skbuff.h>
  48#include <linux/init.h>
  49#include <linux/notifier.h>
  50#include <linux/inetdevice.h>
  51#include <linux/igmp.h>
  52#include <linux/slab.h>
  53#include <linux/hash.h>
  54#ifdef CONFIG_SYSCTL
  55#include <linux/sysctl.h>
  56#endif
  57#include <linux/kmod.h>
  58#include <linux/netconf.h>
  59
  60#include <net/arp.h>
  61#include <net/ip.h>
  62#include <net/route.h>
  63#include <net/ip_fib.h>
  64#include <net/rtnetlink.h>
  65#include <net/net_namespace.h>
  66#include <net/addrconf.h>
  67
  68#include "fib_lookup.h"
  69
  70static struct ipv4_devconf ipv4_devconf = {
  71	.data = {
  72		[IPV4_DEVCONF_ACCEPT_REDIRECTS - 1] = 1,
  73		[IPV4_DEVCONF_SEND_REDIRECTS - 1] = 1,
  74		[IPV4_DEVCONF_SECURE_REDIRECTS - 1] = 1,
  75		[IPV4_DEVCONF_SHARED_MEDIA - 1] = 1,
  76		[IPV4_DEVCONF_IGMPV2_UNSOLICITED_REPORT_INTERVAL - 1] = 10000 /*ms*/,
  77		[IPV4_DEVCONF_IGMPV3_UNSOLICITED_REPORT_INTERVAL - 1] =  1000 /*ms*/,
  78	},
  79};
  80
  81static struct ipv4_devconf ipv4_devconf_dflt = {
  82	.data = {
  83		[IPV4_DEVCONF_ACCEPT_REDIRECTS - 1] = 1,
  84		[IPV4_DEVCONF_SEND_REDIRECTS - 1] = 1,
  85		[IPV4_DEVCONF_SECURE_REDIRECTS - 1] = 1,
  86		[IPV4_DEVCONF_SHARED_MEDIA - 1] = 1,
  87		[IPV4_DEVCONF_ACCEPT_SOURCE_ROUTE - 1] = 1,
  88		[IPV4_DEVCONF_IGMPV2_UNSOLICITED_REPORT_INTERVAL - 1] = 10000 /*ms*/,
  89		[IPV4_DEVCONF_IGMPV3_UNSOLICITED_REPORT_INTERVAL - 1] =  1000 /*ms*/,
  90	},
  91};
  92
  93#define IPV4_DEVCONF_DFLT(net, attr) \
  94	IPV4_DEVCONF((*net->ipv4.devconf_dflt), attr)
  95
  96static const struct nla_policy ifa_ipv4_policy[IFA_MAX+1] = {
  97	[IFA_LOCAL]     	= { .type = NLA_U32 },
  98	[IFA_ADDRESS]   	= { .type = NLA_U32 },
  99	[IFA_BROADCAST] 	= { .type = NLA_U32 },
 100	[IFA_LABEL]     	= { .type = NLA_STRING, .len = IFNAMSIZ - 1 },
 101	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
 102	[IFA_FLAGS]		= { .type = NLA_U32 },
 103};
 104
 105#define IN4_ADDR_HSIZE_SHIFT	8
 106#define IN4_ADDR_HSIZE		(1U << IN4_ADDR_HSIZE_SHIFT)
 107
 
 
 108static struct hlist_head inet_addr_lst[IN4_ADDR_HSIZE];
 
 109
 110static u32 inet_addr_hash(const struct net *net, __be32 addr)
 111{
 112	u32 val = (__force u32) addr ^ net_hash_mix(net);
 113
 114	return hash_32(val, IN4_ADDR_HSIZE_SHIFT);
 
 115}
 116
 117static void inet_hash_insert(struct net *net, struct in_ifaddr *ifa)
 118{
 119	u32 hash = inet_addr_hash(net, ifa->ifa_local);
 120
 121	ASSERT_RTNL();
 122	hlist_add_head_rcu(&ifa->hash, &inet_addr_lst[hash]);
 
 123}
 124
 125static void inet_hash_remove(struct in_ifaddr *ifa)
 126{
 127	ASSERT_RTNL();
 128	hlist_del_init_rcu(&ifa->hash);
 
 129}
 130
 131/**
 132 * __ip_dev_find - find the first device with a given source address.
 133 * @net: the net namespace
 134 * @addr: the source address
 135 * @devref: if true, take a reference on the found device
 136 *
 137 * If a caller uses devref=false, it should be protected by RCU, or RTNL
 138 */
 139struct net_device *__ip_dev_find(struct net *net, __be32 addr, bool devref)
 140{
 141	u32 hash = inet_addr_hash(net, addr);
 142	struct net_device *result = NULL;
 143	struct in_ifaddr *ifa;
 
 144
 145	rcu_read_lock();
 146	hlist_for_each_entry_rcu(ifa, &inet_addr_lst[hash], hash) {
 147		if (ifa->ifa_local == addr) {
 148			struct net_device *dev = ifa->ifa_dev->dev;
 149
 150			if (!net_eq(dev_net(dev), net))
 151				continue;
 
 152			result = dev;
 153			break;
 154		}
 155	}
 156	if (!result) {
 157		struct flowi4 fl4 = { .daddr = addr };
 158		struct fib_result res = { 0 };
 159		struct fib_table *local;
 160
 161		/* Fallback to FIB local table so that communication
 162		 * over loopback subnets work.
 163		 */
 164		local = fib_get_table(net, RT_TABLE_LOCAL);
 165		if (local &&
 166		    !fib_table_lookup(local, &fl4, &res, FIB_LOOKUP_NOREF) &&
 167		    res.type == RTN_LOCAL)
 168			result = FIB_RES_DEV(res);
 169	}
 170	if (result && devref)
 171		dev_hold(result);
 172	rcu_read_unlock();
 173	return result;
 174}
 175EXPORT_SYMBOL(__ip_dev_find);
 176
 177static void rtmsg_ifa(int event, struct in_ifaddr *, struct nlmsghdr *, u32);
 178
 179static BLOCKING_NOTIFIER_HEAD(inetaddr_chain);
 180static void inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap,
 181			 int destroy);
 182#ifdef CONFIG_SYSCTL
 183static int devinet_sysctl_register(struct in_device *idev);
 184static void devinet_sysctl_unregister(struct in_device *idev);
 185#else
 186static int devinet_sysctl_register(struct in_device *idev)
 187{
 188	return 0;
 189}
 190static void devinet_sysctl_unregister(struct in_device *idev)
 191{
 192}
 193#endif
 194
 195/* Locks all the inet devices. */
 196
 197static struct in_ifaddr *inet_alloc_ifa(void)
 198{
 199	return kzalloc(sizeof(struct in_ifaddr), GFP_KERNEL);
 200}
 201
 202static void inet_rcu_free_ifa(struct rcu_head *head)
 203{
 204	struct in_ifaddr *ifa = container_of(head, struct in_ifaddr, rcu_head);
 205	if (ifa->ifa_dev)
 206		in_dev_put(ifa->ifa_dev);
 207	kfree(ifa);
 208}
 209
 210static void inet_free_ifa(struct in_ifaddr *ifa)
 211{
 212	call_rcu(&ifa->rcu_head, inet_rcu_free_ifa);
 213}
 214
 215void in_dev_finish_destroy(struct in_device *idev)
 216{
 217	struct net_device *dev = idev->dev;
 218
 219	WARN_ON(idev->ifa_list);
 220	WARN_ON(idev->mc_list);
 221	kfree(rcu_dereference_protected(idev->mc_hash, 1));
 222#ifdef NET_REFCNT_DEBUG
 223	pr_debug("%s: %p=%s\n", __func__, idev, dev ? dev->name : "NIL");
 224#endif
 225	dev_put(dev);
 226	if (!idev->dead)
 227		pr_err("Freeing alive in_device %p\n", idev);
 228	else
 229		kfree(idev);
 230}
 231EXPORT_SYMBOL(in_dev_finish_destroy);
 232
 233static struct in_device *inetdev_init(struct net_device *dev)
 234{
 235	struct in_device *in_dev;
 236	int err = -ENOMEM;
 237
 238	ASSERT_RTNL();
 239
 240	in_dev = kzalloc(sizeof(*in_dev), GFP_KERNEL);
 241	if (!in_dev)
 242		goto out;
 243	memcpy(&in_dev->cnf, dev_net(dev)->ipv4.devconf_dflt,
 244			sizeof(in_dev->cnf));
 245	in_dev->cnf.sysctl = NULL;
 246	in_dev->dev = dev;
 247	in_dev->arp_parms = neigh_parms_alloc(dev, &arp_tbl);
 248	if (!in_dev->arp_parms)
 249		goto out_kfree;
 250	if (IPV4_DEVCONF(in_dev->cnf, FORWARDING))
 251		dev_disable_lro(dev);
 252	/* Reference in_dev->dev */
 253	dev_hold(dev);
 254	/* Account for reference dev->ip_ptr (below) */
 255	in_dev_hold(in_dev);
 256
 257	err = devinet_sysctl_register(in_dev);
 258	if (err) {
 259		in_dev->dead = 1;
 260		in_dev_put(in_dev);
 261		in_dev = NULL;
 262		goto out;
 263	}
 264	ip_mc_init_dev(in_dev);
 265	if (dev->flags & IFF_UP)
 266		ip_mc_up(in_dev);
 267
 268	/* we can receive as soon as ip_ptr is set -- do this last */
 269	rcu_assign_pointer(dev->ip_ptr, in_dev);
 270out:
 271	return in_dev ?: ERR_PTR(err);
 272out_kfree:
 273	kfree(in_dev);
 274	in_dev = NULL;
 275	goto out;
 276}
 277
 278static void in_dev_rcu_put(struct rcu_head *head)
 279{
 280	struct in_device *idev = container_of(head, struct in_device, rcu_head);
 281	in_dev_put(idev);
 282}
 283
 284static void inetdev_destroy(struct in_device *in_dev)
 285{
 286	struct in_ifaddr *ifa;
 287	struct net_device *dev;
 288
 289	ASSERT_RTNL();
 290
 291	dev = in_dev->dev;
 292
 293	in_dev->dead = 1;
 294
 295	ip_mc_destroy_dev(in_dev);
 296
 297	while ((ifa = in_dev->ifa_list) != NULL) {
 298		inet_del_ifa(in_dev, &in_dev->ifa_list, 0);
 299		inet_free_ifa(ifa);
 300	}
 301
 302	RCU_INIT_POINTER(dev->ip_ptr, NULL);
 303
 304	devinet_sysctl_unregister(in_dev);
 305	neigh_parms_release(&arp_tbl, in_dev->arp_parms);
 306	arp_ifdown(dev);
 307
 308	call_rcu(&in_dev->rcu_head, in_dev_rcu_put);
 309}
 310
 311int inet_addr_onlink(struct in_device *in_dev, __be32 a, __be32 b)
 312{
 313	rcu_read_lock();
 314	for_primary_ifa(in_dev) {
 315		if (inet_ifa_match(a, ifa)) {
 316			if (!b || inet_ifa_match(b, ifa)) {
 317				rcu_read_unlock();
 318				return 1;
 319			}
 320		}
 321	} endfor_ifa(in_dev);
 322	rcu_read_unlock();
 323	return 0;
 324}
 325
 326static void __inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap,
 327			 int destroy, struct nlmsghdr *nlh, u32 portid)
 328{
 329	struct in_ifaddr *promote = NULL;
 330	struct in_ifaddr *ifa, *ifa1 = *ifap;
 331	struct in_ifaddr *last_prim = in_dev->ifa_list;
 332	struct in_ifaddr *prev_prom = NULL;
 333	int do_promote = IN_DEV_PROMOTE_SECONDARIES(in_dev);
 334
 335	ASSERT_RTNL();
 336
 337	if (in_dev->dead)
 338		goto no_promotions;
 339
 340	/* 1. Deleting primary ifaddr forces deletion all secondaries
 341	 * unless alias promotion is set
 342	 **/
 343
 344	if (!(ifa1->ifa_flags & IFA_F_SECONDARY)) {
 345		struct in_ifaddr **ifap1 = &ifa1->ifa_next;
 346
 347		while ((ifa = *ifap1) != NULL) {
 348			if (!(ifa->ifa_flags & IFA_F_SECONDARY) &&
 349			    ifa1->ifa_scope <= ifa->ifa_scope)
 350				last_prim = ifa;
 351
 352			if (!(ifa->ifa_flags & IFA_F_SECONDARY) ||
 353			    ifa1->ifa_mask != ifa->ifa_mask ||
 354			    !inet_ifa_match(ifa1->ifa_address, ifa)) {
 355				ifap1 = &ifa->ifa_next;
 356				prev_prom = ifa;
 357				continue;
 358			}
 359
 360			if (!do_promote) {
 361				inet_hash_remove(ifa);
 362				*ifap1 = ifa->ifa_next;
 363
 364				rtmsg_ifa(RTM_DELADDR, ifa, nlh, portid);
 365				blocking_notifier_call_chain(&inetaddr_chain,
 366						NETDEV_DOWN, ifa);
 367				inet_free_ifa(ifa);
 368			} else {
 369				promote = ifa;
 370				break;
 371			}
 372		}
 373	}
 374
 375	/* On promotion all secondaries from subnet are changing
 376	 * the primary IP, we must remove all their routes silently
 377	 * and later to add them back with new prefsrc. Do this
 378	 * while all addresses are on the device list.
 379	 */
 380	for (ifa = promote; ifa; ifa = ifa->ifa_next) {
 381		if (ifa1->ifa_mask == ifa->ifa_mask &&
 382		    inet_ifa_match(ifa1->ifa_address, ifa))
 383			fib_del_ifaddr(ifa, ifa1);
 384	}
 385
 386no_promotions:
 387	/* 2. Unlink it */
 388
 389	*ifap = ifa1->ifa_next;
 390	inet_hash_remove(ifa1);
 391
 392	/* 3. Announce address deletion */
 393
 394	/* Send message first, then call notifier.
 395	   At first sight, FIB update triggered by notifier
 396	   will refer to already deleted ifaddr, that could confuse
 397	   netlink listeners. It is not true: look, gated sees
 398	   that route deleted and if it still thinks that ifaddr
 399	   is valid, it will try to restore deleted routes... Grr.
 400	   So that, this order is correct.
 401	 */
 402	rtmsg_ifa(RTM_DELADDR, ifa1, nlh, portid);
 403	blocking_notifier_call_chain(&inetaddr_chain, NETDEV_DOWN, ifa1);
 404
 405	if (promote) {
 406		struct in_ifaddr *next_sec = promote->ifa_next;
 407
 408		if (prev_prom) {
 409			prev_prom->ifa_next = promote->ifa_next;
 410			promote->ifa_next = last_prim->ifa_next;
 411			last_prim->ifa_next = promote;
 412		}
 413
 414		promote->ifa_flags &= ~IFA_F_SECONDARY;
 415		rtmsg_ifa(RTM_NEWADDR, promote, nlh, portid);
 416		blocking_notifier_call_chain(&inetaddr_chain,
 417				NETDEV_UP, promote);
 418		for (ifa = next_sec; ifa; ifa = ifa->ifa_next) {
 419			if (ifa1->ifa_mask != ifa->ifa_mask ||
 420			    !inet_ifa_match(ifa1->ifa_address, ifa))
 421					continue;
 422			fib_add_ifaddr(ifa);
 423		}
 424
 425	}
 426	if (destroy)
 427		inet_free_ifa(ifa1);
 428}
 429
 430static void inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap,
 431			 int destroy)
 432{
 433	__inet_del_ifa(in_dev, ifap, destroy, NULL, 0);
 434}
 435
 436static void check_lifetime(struct work_struct *work);
 437
 438static DECLARE_DELAYED_WORK(check_lifetime_work, check_lifetime);
 439
 440static int __inet_insert_ifa(struct in_ifaddr *ifa, struct nlmsghdr *nlh,
 441			     u32 portid)
 442{
 443	struct in_device *in_dev = ifa->ifa_dev;
 444	struct in_ifaddr *ifa1, **ifap, **last_primary;
 445
 446	ASSERT_RTNL();
 447
 448	if (!ifa->ifa_local) {
 449		inet_free_ifa(ifa);
 450		return 0;
 451	}
 452
 453	ifa->ifa_flags &= ~IFA_F_SECONDARY;
 454	last_primary = &in_dev->ifa_list;
 455
 456	for (ifap = &in_dev->ifa_list; (ifa1 = *ifap) != NULL;
 457	     ifap = &ifa1->ifa_next) {
 458		if (!(ifa1->ifa_flags & IFA_F_SECONDARY) &&
 459		    ifa->ifa_scope <= ifa1->ifa_scope)
 460			last_primary = &ifa1->ifa_next;
 461		if (ifa1->ifa_mask == ifa->ifa_mask &&
 462		    inet_ifa_match(ifa1->ifa_address, ifa)) {
 463			if (ifa1->ifa_local == ifa->ifa_local) {
 464				inet_free_ifa(ifa);
 465				return -EEXIST;
 466			}
 467			if (ifa1->ifa_scope != ifa->ifa_scope) {
 468				inet_free_ifa(ifa);
 469				return -EINVAL;
 470			}
 471			ifa->ifa_flags |= IFA_F_SECONDARY;
 472		}
 473	}
 474
 475	if (!(ifa->ifa_flags & IFA_F_SECONDARY)) {
 476		prandom_seed((__force u32) ifa->ifa_local);
 477		ifap = last_primary;
 478	}
 479
 480	ifa->ifa_next = *ifap;
 481	*ifap = ifa;
 482
 483	inet_hash_insert(dev_net(in_dev->dev), ifa);
 484
 485	cancel_delayed_work(&check_lifetime_work);
 486	queue_delayed_work(system_power_efficient_wq, &check_lifetime_work, 0);
 487
 488	/* Send message first, then call notifier.
 489	   Notifier will trigger FIB update, so that
 490	   listeners of netlink will know about new ifaddr */
 491	rtmsg_ifa(RTM_NEWADDR, ifa, nlh, portid);
 492	blocking_notifier_call_chain(&inetaddr_chain, NETDEV_UP, ifa);
 493
 494	return 0;
 495}
 496
 497static int inet_insert_ifa(struct in_ifaddr *ifa)
 498{
 499	return __inet_insert_ifa(ifa, NULL, 0);
 500}
 501
 502static int inet_set_ifa(struct net_device *dev, struct in_ifaddr *ifa)
 503{
 504	struct in_device *in_dev = __in_dev_get_rtnl(dev);
 505
 506	ASSERT_RTNL();
 507
 508	if (!in_dev) {
 509		inet_free_ifa(ifa);
 510		return -ENOBUFS;
 511	}
 512	ipv4_devconf_setall(in_dev);
 513	neigh_parms_data_state_setall(in_dev->arp_parms);
 514	if (ifa->ifa_dev != in_dev) {
 515		WARN_ON(ifa->ifa_dev);
 516		in_dev_hold(in_dev);
 517		ifa->ifa_dev = in_dev;
 518	}
 519	if (ipv4_is_loopback(ifa->ifa_local))
 520		ifa->ifa_scope = RT_SCOPE_HOST;
 521	return inet_insert_ifa(ifa);
 522}
 523
 524/* Caller must hold RCU or RTNL :
 525 * We dont take a reference on found in_device
 526 */
 527struct in_device *inetdev_by_index(struct net *net, int ifindex)
 528{
 529	struct net_device *dev;
 530	struct in_device *in_dev = NULL;
 531
 532	rcu_read_lock();
 533	dev = dev_get_by_index_rcu(net, ifindex);
 534	if (dev)
 535		in_dev = rcu_dereference_rtnl(dev->ip_ptr);
 536	rcu_read_unlock();
 537	return in_dev;
 538}
 539EXPORT_SYMBOL(inetdev_by_index);
 540
 541/* Called only from RTNL semaphored context. No locks. */
 542
 543struct in_ifaddr *inet_ifa_byprefix(struct in_device *in_dev, __be32 prefix,
 544				    __be32 mask)
 545{
 546	ASSERT_RTNL();
 547
 548	for_primary_ifa(in_dev) {
 549		if (ifa->ifa_mask == mask && inet_ifa_match(prefix, ifa))
 550			return ifa;
 551	} endfor_ifa(in_dev);
 552	return NULL;
 553}
 554
 555static int ip_mc_config(struct sock *sk, bool join, const struct in_ifaddr *ifa)
 556{
 557	struct ip_mreqn mreq = {
 558		.imr_multiaddr.s_addr = ifa->ifa_address,
 559		.imr_ifindex = ifa->ifa_dev->dev->ifindex,
 560	};
 561	int ret;
 562
 563	ASSERT_RTNL();
 564
 565	lock_sock(sk);
 566	if (join)
 567		ret = ip_mc_join_group(sk, &mreq);
 568	else
 569		ret = ip_mc_leave_group(sk, &mreq);
 570	release_sock(sk);
 571
 572	return ret;
 573}
 574
 575static int inet_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh)
 576{
 577	struct net *net = sock_net(skb->sk);
 578	struct nlattr *tb[IFA_MAX+1];
 579	struct in_device *in_dev;
 580	struct ifaddrmsg *ifm;
 581	struct in_ifaddr *ifa, **ifap;
 582	int err = -EINVAL;
 583
 584	ASSERT_RTNL();
 585
 586	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv4_policy);
 587	if (err < 0)
 588		goto errout;
 589
 590	ifm = nlmsg_data(nlh);
 591	in_dev = inetdev_by_index(net, ifm->ifa_index);
 592	if (!in_dev) {
 593		err = -ENODEV;
 594		goto errout;
 595	}
 596
 597	for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL;
 598	     ifap = &ifa->ifa_next) {
 599		if (tb[IFA_LOCAL] &&
 600		    ifa->ifa_local != nla_get_in_addr(tb[IFA_LOCAL]))
 601			continue;
 602
 603		if (tb[IFA_LABEL] && nla_strcmp(tb[IFA_LABEL], ifa->ifa_label))
 604			continue;
 605
 606		if (tb[IFA_ADDRESS] &&
 607		    (ifm->ifa_prefixlen != ifa->ifa_prefixlen ||
 608		    !inet_ifa_match(nla_get_in_addr(tb[IFA_ADDRESS]), ifa)))
 609			continue;
 610
 611		if (ipv4_is_multicast(ifa->ifa_address))
 612			ip_mc_config(net->ipv4.mc_autojoin_sk, false, ifa);
 613		__inet_del_ifa(in_dev, ifap, 1, nlh, NETLINK_CB(skb).portid);
 614		return 0;
 615	}
 616
 617	err = -EADDRNOTAVAIL;
 618errout:
 619	return err;
 620}
 621
 622#define INFINITY_LIFE_TIME	0xFFFFFFFF
 623
 624static void check_lifetime(struct work_struct *work)
 625{
 626	unsigned long now, next, next_sec, next_sched;
 627	struct in_ifaddr *ifa;
 628	struct hlist_node *n;
 629	int i;
 630
 631	now = jiffies;
 632	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
 633
 634	for (i = 0; i < IN4_ADDR_HSIZE; i++) {
 635		bool change_needed = false;
 636
 637		rcu_read_lock();
 638		hlist_for_each_entry_rcu(ifa, &inet_addr_lst[i], hash) {
 639			unsigned long age;
 640
 641			if (ifa->ifa_flags & IFA_F_PERMANENT)
 642				continue;
 643
 644			/* We try to batch several events at once. */
 645			age = (now - ifa->ifa_tstamp +
 646			       ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
 647
 648			if (ifa->ifa_valid_lft != INFINITY_LIFE_TIME &&
 649			    age >= ifa->ifa_valid_lft) {
 650				change_needed = true;
 651			} else if (ifa->ifa_preferred_lft ==
 652				   INFINITY_LIFE_TIME) {
 653				continue;
 654			} else if (age >= ifa->ifa_preferred_lft) {
 655				if (time_before(ifa->ifa_tstamp +
 656						ifa->ifa_valid_lft * HZ, next))
 657					next = ifa->ifa_tstamp +
 658					       ifa->ifa_valid_lft * HZ;
 659
 660				if (!(ifa->ifa_flags & IFA_F_DEPRECATED))
 661					change_needed = true;
 662			} else if (time_before(ifa->ifa_tstamp +
 663					       ifa->ifa_preferred_lft * HZ,
 664					       next)) {
 665				next = ifa->ifa_tstamp +
 666				       ifa->ifa_preferred_lft * HZ;
 667			}
 668		}
 669		rcu_read_unlock();
 670		if (!change_needed)
 671			continue;
 672		rtnl_lock();
 673		hlist_for_each_entry_safe(ifa, n, &inet_addr_lst[i], hash) {
 674			unsigned long age;
 675
 676			if (ifa->ifa_flags & IFA_F_PERMANENT)
 677				continue;
 678
 679			/* We try to batch several events at once. */
 680			age = (now - ifa->ifa_tstamp +
 681			       ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
 682
 683			if (ifa->ifa_valid_lft != INFINITY_LIFE_TIME &&
 684			    age >= ifa->ifa_valid_lft) {
 685				struct in_ifaddr **ifap;
 686
 687				for (ifap = &ifa->ifa_dev->ifa_list;
 688				     *ifap != NULL; ifap = &(*ifap)->ifa_next) {
 689					if (*ifap == ifa) {
 690						inet_del_ifa(ifa->ifa_dev,
 691							     ifap, 1);
 692						break;
 693					}
 694				}
 695			} else if (ifa->ifa_preferred_lft !=
 696				   INFINITY_LIFE_TIME &&
 697				   age >= ifa->ifa_preferred_lft &&
 698				   !(ifa->ifa_flags & IFA_F_DEPRECATED)) {
 699				ifa->ifa_flags |= IFA_F_DEPRECATED;
 700				rtmsg_ifa(RTM_NEWADDR, ifa, NULL, 0);
 701			}
 702		}
 703		rtnl_unlock();
 704	}
 705
 706	next_sec = round_jiffies_up(next);
 707	next_sched = next;
 708
 709	/* If rounded timeout is accurate enough, accept it. */
 710	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
 711		next_sched = next_sec;
 712
 713	now = jiffies;
 714	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
 715	if (time_before(next_sched, now + ADDRCONF_TIMER_FUZZ_MAX))
 716		next_sched = now + ADDRCONF_TIMER_FUZZ_MAX;
 717
 718	queue_delayed_work(system_power_efficient_wq, &check_lifetime_work,
 719			next_sched - now);
 720}
 721
 722static void set_ifa_lifetime(struct in_ifaddr *ifa, __u32 valid_lft,
 723			     __u32 prefered_lft)
 724{
 725	unsigned long timeout;
 726
 727	ifa->ifa_flags &= ~(IFA_F_PERMANENT | IFA_F_DEPRECATED);
 728
 729	timeout = addrconf_timeout_fixup(valid_lft, HZ);
 730	if (addrconf_finite_timeout(timeout))
 731		ifa->ifa_valid_lft = timeout;
 732	else
 733		ifa->ifa_flags |= IFA_F_PERMANENT;
 734
 735	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
 736	if (addrconf_finite_timeout(timeout)) {
 737		if (timeout == 0)
 738			ifa->ifa_flags |= IFA_F_DEPRECATED;
 739		ifa->ifa_preferred_lft = timeout;
 740	}
 741	ifa->ifa_tstamp = jiffies;
 742	if (!ifa->ifa_cstamp)
 743		ifa->ifa_cstamp = ifa->ifa_tstamp;
 744}
 745
 746static struct in_ifaddr *rtm_to_ifaddr(struct net *net, struct nlmsghdr *nlh,
 747				       __u32 *pvalid_lft, __u32 *pprefered_lft)
 748{
 749	struct nlattr *tb[IFA_MAX+1];
 750	struct in_ifaddr *ifa;
 751	struct ifaddrmsg *ifm;
 752	struct net_device *dev;
 753	struct in_device *in_dev;
 754	int err;
 755
 756	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv4_policy);
 757	if (err < 0)
 758		goto errout;
 759
 760	ifm = nlmsg_data(nlh);
 761	err = -EINVAL;
 762	if (ifm->ifa_prefixlen > 32 || !tb[IFA_LOCAL])
 763		goto errout;
 764
 765	dev = __dev_get_by_index(net, ifm->ifa_index);
 766	err = -ENODEV;
 767	if (!dev)
 768		goto errout;
 769
 770	in_dev = __in_dev_get_rtnl(dev);
 771	err = -ENOBUFS;
 772	if (!in_dev)
 773		goto errout;
 774
 775	ifa = inet_alloc_ifa();
 776	if (!ifa)
 777		/*
 778		 * A potential indev allocation can be left alive, it stays
 779		 * assigned to its device and is destroy with it.
 780		 */
 781		goto errout;
 782
 783	ipv4_devconf_setall(in_dev);
 784	neigh_parms_data_state_setall(in_dev->arp_parms);
 785	in_dev_hold(in_dev);
 786
 787	if (!tb[IFA_ADDRESS])
 788		tb[IFA_ADDRESS] = tb[IFA_LOCAL];
 789
 790	INIT_HLIST_NODE(&ifa->hash);
 791	ifa->ifa_prefixlen = ifm->ifa_prefixlen;
 792	ifa->ifa_mask = inet_make_mask(ifm->ifa_prefixlen);
 793	ifa->ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) :
 794					 ifm->ifa_flags;
 795	ifa->ifa_scope = ifm->ifa_scope;
 796	ifa->ifa_dev = in_dev;
 797
 798	ifa->ifa_local = nla_get_in_addr(tb[IFA_LOCAL]);
 799	ifa->ifa_address = nla_get_in_addr(tb[IFA_ADDRESS]);
 800
 801	if (tb[IFA_BROADCAST])
 802		ifa->ifa_broadcast = nla_get_in_addr(tb[IFA_BROADCAST]);
 803
 804	if (tb[IFA_LABEL])
 805		nla_strlcpy(ifa->ifa_label, tb[IFA_LABEL], IFNAMSIZ);
 806	else
 807		memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
 808
 809	if (tb[IFA_CACHEINFO]) {
 810		struct ifa_cacheinfo *ci;
 811
 812		ci = nla_data(tb[IFA_CACHEINFO]);
 813		if (!ci->ifa_valid || ci->ifa_prefered > ci->ifa_valid) {
 814			err = -EINVAL;
 815			goto errout_free;
 816		}
 817		*pvalid_lft = ci->ifa_valid;
 818		*pprefered_lft = ci->ifa_prefered;
 819	}
 820
 821	return ifa;
 822
 823errout_free:
 824	inet_free_ifa(ifa);
 825errout:
 826	return ERR_PTR(err);
 827}
 828
 829static struct in_ifaddr *find_matching_ifa(struct in_ifaddr *ifa)
 830{
 831	struct in_device *in_dev = ifa->ifa_dev;
 832	struct in_ifaddr *ifa1, **ifap;
 833
 834	if (!ifa->ifa_local)
 835		return NULL;
 836
 837	for (ifap = &in_dev->ifa_list; (ifa1 = *ifap) != NULL;
 838	     ifap = &ifa1->ifa_next) {
 839		if (ifa1->ifa_mask == ifa->ifa_mask &&
 840		    inet_ifa_match(ifa1->ifa_address, ifa) &&
 841		    ifa1->ifa_local == ifa->ifa_local)
 842			return ifa1;
 843	}
 844	return NULL;
 845}
 846
 847static int inet_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh)
 848{
 849	struct net *net = sock_net(skb->sk);
 850	struct in_ifaddr *ifa;
 851	struct in_ifaddr *ifa_existing;
 852	__u32 valid_lft = INFINITY_LIFE_TIME;
 853	__u32 prefered_lft = INFINITY_LIFE_TIME;
 854
 855	ASSERT_RTNL();
 856
 857	ifa = rtm_to_ifaddr(net, nlh, &valid_lft, &prefered_lft);
 858	if (IS_ERR(ifa))
 859		return PTR_ERR(ifa);
 860
 861	ifa_existing = find_matching_ifa(ifa);
 862	if (!ifa_existing) {
 863		/* It would be best to check for !NLM_F_CREATE here but
 864		 * userspace already relies on not having to provide this.
 865		 */
 866		set_ifa_lifetime(ifa, valid_lft, prefered_lft);
 867		if (ifa->ifa_flags & IFA_F_MCAUTOJOIN) {
 868			int ret = ip_mc_config(net->ipv4.mc_autojoin_sk,
 869					       true, ifa);
 870
 871			if (ret < 0) {
 872				inet_free_ifa(ifa);
 873				return ret;
 874			}
 875		}
 876		return __inet_insert_ifa(ifa, nlh, NETLINK_CB(skb).portid);
 877	} else {
 878		inet_free_ifa(ifa);
 879
 880		if (nlh->nlmsg_flags & NLM_F_EXCL ||
 881		    !(nlh->nlmsg_flags & NLM_F_REPLACE))
 882			return -EEXIST;
 883		ifa = ifa_existing;
 884		set_ifa_lifetime(ifa, valid_lft, prefered_lft);
 885		cancel_delayed_work(&check_lifetime_work);
 886		queue_delayed_work(system_power_efficient_wq,
 887				&check_lifetime_work, 0);
 888		rtmsg_ifa(RTM_NEWADDR, ifa, nlh, NETLINK_CB(skb).portid);
 889	}
 890	return 0;
 891}
 892
 893/*
 894 *	Determine a default network mask, based on the IP address.
 895 */
 896
 897static int inet_abc_len(__be32 addr)
 898{
 899	int rc = -1;	/* Something else, probably a multicast. */
 900
 901	if (ipv4_is_zeronet(addr))
 902		rc = 0;
 903	else {
 904		__u32 haddr = ntohl(addr);
 905
 906		if (IN_CLASSA(haddr))
 907			rc = 8;
 908		else if (IN_CLASSB(haddr))
 909			rc = 16;
 910		else if (IN_CLASSC(haddr))
 911			rc = 24;
 912	}
 913
 914	return rc;
 915}
 916
 917
 918int devinet_ioctl(struct net *net, unsigned int cmd, void __user *arg)
 919{
 920	struct ifreq ifr;
 921	struct sockaddr_in sin_orig;
 922	struct sockaddr_in *sin = (struct sockaddr_in *)&ifr.ifr_addr;
 923	struct in_device *in_dev;
 924	struct in_ifaddr **ifap = NULL;
 925	struct in_ifaddr *ifa = NULL;
 926	struct net_device *dev;
 927	char *colon;
 928	int ret = -EFAULT;
 929	int tryaddrmatch = 0;
 930
 931	/*
 932	 *	Fetch the caller's info block into kernel space
 933	 */
 934
 935	if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
 936		goto out;
 937	ifr.ifr_name[IFNAMSIZ - 1] = 0;
 938
 939	/* save original address for comparison */
 940	memcpy(&sin_orig, sin, sizeof(*sin));
 941
 942	colon = strchr(ifr.ifr_name, ':');
 943	if (colon)
 944		*colon = 0;
 945
 946	dev_load(net, ifr.ifr_name);
 947
 948	switch (cmd) {
 949	case SIOCGIFADDR:	/* Get interface address */
 950	case SIOCGIFBRDADDR:	/* Get the broadcast address */
 951	case SIOCGIFDSTADDR:	/* Get the destination address */
 952	case SIOCGIFNETMASK:	/* Get the netmask for the interface */
 953		/* Note that these ioctls will not sleep,
 954		   so that we do not impose a lock.
 955		   One day we will be forced to put shlock here (I mean SMP)
 956		 */
 957		tryaddrmatch = (sin_orig.sin_family == AF_INET);
 958		memset(sin, 0, sizeof(*sin));
 959		sin->sin_family = AF_INET;
 960		break;
 961
 962	case SIOCSIFFLAGS:
 963		ret = -EPERM;
 964		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 965			goto out;
 966		break;
 967	case SIOCSIFADDR:	/* Set interface address (and family) */
 968	case SIOCSIFBRDADDR:	/* Set the broadcast address */
 969	case SIOCSIFDSTADDR:	/* Set the destination address */
 970	case SIOCSIFNETMASK: 	/* Set the netmask for the interface */
 971		ret = -EPERM;
 972		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 973			goto out;
 974		ret = -EINVAL;
 975		if (sin->sin_family != AF_INET)
 976			goto out;
 977		break;
 978	default:
 979		ret = -EINVAL;
 980		goto out;
 981	}
 982
 983	rtnl_lock();
 984
 985	ret = -ENODEV;
 986	dev = __dev_get_by_name(net, ifr.ifr_name);
 987	if (!dev)
 988		goto done;
 989
 990	if (colon)
 991		*colon = ':';
 992
 993	in_dev = __in_dev_get_rtnl(dev);
 994	if (in_dev) {
 995		if (tryaddrmatch) {
 996			/* Matthias Andree */
 997			/* compare label and address (4.4BSD style) */
 998			/* note: we only do this for a limited set of ioctls
 999			   and only if the original address family was AF_INET.
1000			   This is checked above. */
1001			for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL;
1002			     ifap = &ifa->ifa_next) {
1003				if (!strcmp(ifr.ifr_name, ifa->ifa_label) &&
1004				    sin_orig.sin_addr.s_addr ==
1005							ifa->ifa_local) {
1006					break; /* found */
1007				}
1008			}
1009		}
1010		/* we didn't get a match, maybe the application is
1011		   4.3BSD-style and passed in junk so we fall back to
1012		   comparing just the label */
1013		if (!ifa) {
1014			for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL;
1015			     ifap = &ifa->ifa_next)
1016				if (!strcmp(ifr.ifr_name, ifa->ifa_label))
1017					break;
1018		}
1019	}
1020
1021	ret = -EADDRNOTAVAIL;
1022	if (!ifa && cmd != SIOCSIFADDR && cmd != SIOCSIFFLAGS)
1023		goto done;
1024
1025	switch (cmd) {
1026	case SIOCGIFADDR:	/* Get interface address */
1027		sin->sin_addr.s_addr = ifa->ifa_local;
1028		goto rarok;
1029
1030	case SIOCGIFBRDADDR:	/* Get the broadcast address */
1031		sin->sin_addr.s_addr = ifa->ifa_broadcast;
1032		goto rarok;
1033
1034	case SIOCGIFDSTADDR:	/* Get the destination address */
1035		sin->sin_addr.s_addr = ifa->ifa_address;
1036		goto rarok;
1037
1038	case SIOCGIFNETMASK:	/* Get the netmask for the interface */
1039		sin->sin_addr.s_addr = ifa->ifa_mask;
1040		goto rarok;
1041
1042	case SIOCSIFFLAGS:
1043		if (colon) {
1044			ret = -EADDRNOTAVAIL;
1045			if (!ifa)
1046				break;
1047			ret = 0;
1048			if (!(ifr.ifr_flags & IFF_UP))
1049				inet_del_ifa(in_dev, ifap, 1);
1050			break;
1051		}
1052		ret = dev_change_flags(dev, ifr.ifr_flags);
1053		break;
1054
1055	case SIOCSIFADDR:	/* Set interface address (and family) */
1056		ret = -EINVAL;
1057		if (inet_abc_len(sin->sin_addr.s_addr) < 0)
1058			break;
1059
1060		if (!ifa) {
1061			ret = -ENOBUFS;
1062			ifa = inet_alloc_ifa();
 
1063			if (!ifa)
1064				break;
1065			INIT_HLIST_NODE(&ifa->hash);
1066			if (colon)
1067				memcpy(ifa->ifa_label, ifr.ifr_name, IFNAMSIZ);
1068			else
1069				memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
1070		} else {
1071			ret = 0;
1072			if (ifa->ifa_local == sin->sin_addr.s_addr)
1073				break;
1074			inet_del_ifa(in_dev, ifap, 0);
1075			ifa->ifa_broadcast = 0;
1076			ifa->ifa_scope = 0;
1077		}
1078
1079		ifa->ifa_address = ifa->ifa_local = sin->sin_addr.s_addr;
1080
1081		if (!(dev->flags & IFF_POINTOPOINT)) {
1082			ifa->ifa_prefixlen = inet_abc_len(ifa->ifa_address);
1083			ifa->ifa_mask = inet_make_mask(ifa->ifa_prefixlen);
1084			if ((dev->flags & IFF_BROADCAST) &&
1085			    ifa->ifa_prefixlen < 31)
1086				ifa->ifa_broadcast = ifa->ifa_address |
1087						     ~ifa->ifa_mask;
1088		} else {
1089			ifa->ifa_prefixlen = 32;
1090			ifa->ifa_mask = inet_make_mask(32);
1091		}
1092		set_ifa_lifetime(ifa, INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
1093		ret = inet_set_ifa(dev, ifa);
1094		break;
1095
1096	case SIOCSIFBRDADDR:	/* Set the broadcast address */
1097		ret = 0;
1098		if (ifa->ifa_broadcast != sin->sin_addr.s_addr) {
1099			inet_del_ifa(in_dev, ifap, 0);
1100			ifa->ifa_broadcast = sin->sin_addr.s_addr;
1101			inet_insert_ifa(ifa);
1102		}
1103		break;
1104
1105	case SIOCSIFDSTADDR:	/* Set the destination address */
1106		ret = 0;
1107		if (ifa->ifa_address == sin->sin_addr.s_addr)
1108			break;
1109		ret = -EINVAL;
1110		if (inet_abc_len(sin->sin_addr.s_addr) < 0)
1111			break;
1112		ret = 0;
1113		inet_del_ifa(in_dev, ifap, 0);
1114		ifa->ifa_address = sin->sin_addr.s_addr;
1115		inet_insert_ifa(ifa);
1116		break;
1117
1118	case SIOCSIFNETMASK: 	/* Set the netmask for the interface */
1119
1120		/*
1121		 *	The mask we set must be legal.
1122		 */
1123		ret = -EINVAL;
1124		if (bad_mask(sin->sin_addr.s_addr, 0))
1125			break;
1126		ret = 0;
1127		if (ifa->ifa_mask != sin->sin_addr.s_addr) {
1128			__be32 old_mask = ifa->ifa_mask;
1129			inet_del_ifa(in_dev, ifap, 0);
1130			ifa->ifa_mask = sin->sin_addr.s_addr;
1131			ifa->ifa_prefixlen = inet_mask_len(ifa->ifa_mask);
1132
1133			/* See if current broadcast address matches
1134			 * with current netmask, then recalculate
1135			 * the broadcast address. Otherwise it's a
1136			 * funny address, so don't touch it since
1137			 * the user seems to know what (s)he's doing...
1138			 */
1139			if ((dev->flags & IFF_BROADCAST) &&
1140			    (ifa->ifa_prefixlen < 31) &&
1141			    (ifa->ifa_broadcast ==
1142			     (ifa->ifa_local|~old_mask))) {
1143				ifa->ifa_broadcast = (ifa->ifa_local |
1144						      ~sin->sin_addr.s_addr);
1145			}
1146			inet_insert_ifa(ifa);
1147		}
1148		break;
1149	}
1150done:
1151	rtnl_unlock();
1152out:
1153	return ret;
1154rarok:
1155	rtnl_unlock();
1156	ret = copy_to_user(arg, &ifr, sizeof(struct ifreq)) ? -EFAULT : 0;
1157	goto out;
1158}
1159
1160static int inet_gifconf(struct net_device *dev, char __user *buf, int len)
1161{
1162	struct in_device *in_dev = __in_dev_get_rtnl(dev);
1163	struct in_ifaddr *ifa;
1164	struct ifreq ifr;
1165	int done = 0;
1166
1167	if (!in_dev)
1168		goto out;
1169
1170	for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
1171		if (!buf) {
1172			done += sizeof(ifr);
1173			continue;
1174		}
1175		if (len < (int) sizeof(ifr))
1176			break;
1177		memset(&ifr, 0, sizeof(struct ifreq));
1178		strcpy(ifr.ifr_name, ifa->ifa_label);
 
 
 
1179
1180		(*(struct sockaddr_in *)&ifr.ifr_addr).sin_family = AF_INET;
1181		(*(struct sockaddr_in *)&ifr.ifr_addr).sin_addr.s_addr =
1182								ifa->ifa_local;
1183
1184		if (copy_to_user(buf, &ifr, sizeof(struct ifreq))) {
1185			done = -EFAULT;
1186			break;
1187		}
1188		buf  += sizeof(struct ifreq);
1189		len  -= sizeof(struct ifreq);
1190		done += sizeof(struct ifreq);
1191	}
1192out:
1193	return done;
1194}
1195
1196__be32 inet_select_addr(const struct net_device *dev, __be32 dst, int scope)
1197{
1198	__be32 addr = 0;
1199	struct in_device *in_dev;
1200	struct net *net = dev_net(dev);
1201	int master_idx;
1202
1203	rcu_read_lock();
1204	in_dev = __in_dev_get_rcu(dev);
1205	if (!in_dev)
1206		goto no_in_dev;
1207
1208	for_primary_ifa(in_dev) {
1209		if (ifa->ifa_scope > scope)
1210			continue;
1211		if (!dst || inet_ifa_match(dst, ifa)) {
1212			addr = ifa->ifa_local;
1213			break;
1214		}
1215		if (!addr)
1216			addr = ifa->ifa_local;
1217	} endfor_ifa(in_dev);
1218
1219	if (addr)
1220		goto out_unlock;
1221no_in_dev:
1222	master_idx = l3mdev_master_ifindex_rcu(dev);
1223
1224	/* For VRFs, the VRF device takes the place of the loopback device,
1225	 * with addresses on it being preferred.  Note in such cases the
1226	 * loopback device will be among the devices that fail the master_idx
1227	 * equality check in the loop below.
1228	 */
1229	if (master_idx &&
1230	    (dev = dev_get_by_index_rcu(net, master_idx)) &&
1231	    (in_dev = __in_dev_get_rcu(dev))) {
1232		for_primary_ifa(in_dev) {
1233			if (ifa->ifa_scope != RT_SCOPE_LINK &&
1234			    ifa->ifa_scope <= scope) {
1235				addr = ifa->ifa_local;
1236				goto out_unlock;
1237			}
1238		} endfor_ifa(in_dev);
1239	}
1240
1241	/* Not loopback addresses on loopback should be preferred
1242	   in this case. It is important that lo is the first interface
1243	   in dev_base list.
1244	 */
1245	for_each_netdev_rcu(net, dev) {
1246		if (l3mdev_master_ifindex_rcu(dev) != master_idx)
1247			continue;
1248
1249		in_dev = __in_dev_get_rcu(dev);
1250		if (!in_dev)
1251			continue;
1252
1253		for_primary_ifa(in_dev) {
1254			if (ifa->ifa_scope != RT_SCOPE_LINK &&
1255			    ifa->ifa_scope <= scope) {
1256				addr = ifa->ifa_local;
1257				goto out_unlock;
1258			}
1259		} endfor_ifa(in_dev);
1260	}
1261out_unlock:
1262	rcu_read_unlock();
1263	return addr;
1264}
1265EXPORT_SYMBOL(inet_select_addr);
1266
1267static __be32 confirm_addr_indev(struct in_device *in_dev, __be32 dst,
1268			      __be32 local, int scope)
1269{
1270	int same = 0;
1271	__be32 addr = 0;
1272
1273	for_ifa(in_dev) {
1274		if (!addr &&
1275		    (local == ifa->ifa_local || !local) &&
1276		    ifa->ifa_scope <= scope) {
1277			addr = ifa->ifa_local;
1278			if (same)
1279				break;
1280		}
1281		if (!same) {
1282			same = (!local || inet_ifa_match(local, ifa)) &&
1283				(!dst || inet_ifa_match(dst, ifa));
1284			if (same && addr) {
1285				if (local || !dst)
1286					break;
1287				/* Is the selected addr into dst subnet? */
1288				if (inet_ifa_match(addr, ifa))
1289					break;
1290				/* No, then can we use new local src? */
1291				if (ifa->ifa_scope <= scope) {
1292					addr = ifa->ifa_local;
1293					break;
1294				}
1295				/* search for large dst subnet for addr */
1296				same = 0;
1297			}
1298		}
1299	} endfor_ifa(in_dev);
1300
1301	return same ? addr : 0;
1302}
1303
1304/*
1305 * Confirm that local IP address exists using wildcards:
1306 * - net: netns to check, cannot be NULL
1307 * - in_dev: only on this interface, NULL=any interface
1308 * - dst: only in the same subnet as dst, 0=any dst
1309 * - local: address, 0=autoselect the local address
1310 * - scope: maximum allowed scope value for the local address
1311 */
1312__be32 inet_confirm_addr(struct net *net, struct in_device *in_dev,
1313			 __be32 dst, __be32 local, int scope)
1314{
1315	__be32 addr = 0;
1316	struct net_device *dev;
 
1317
1318	if (in_dev)
1319		return confirm_addr_indev(in_dev, dst, local, scope);
1320
 
1321	rcu_read_lock();
1322	for_each_netdev_rcu(net, dev) {
1323		in_dev = __in_dev_get_rcu(dev);
1324		if (in_dev) {
1325			addr = confirm_addr_indev(in_dev, dst, local, scope);
1326			if (addr)
1327				break;
1328		}
1329	}
1330	rcu_read_unlock();
1331
1332	return addr;
1333}
1334EXPORT_SYMBOL(inet_confirm_addr);
1335
1336/*
1337 *	Device notifier
1338 */
1339
1340int register_inetaddr_notifier(struct notifier_block *nb)
1341{
1342	return blocking_notifier_chain_register(&inetaddr_chain, nb);
1343}
1344EXPORT_SYMBOL(register_inetaddr_notifier);
1345
1346int unregister_inetaddr_notifier(struct notifier_block *nb)
1347{
1348	return blocking_notifier_chain_unregister(&inetaddr_chain, nb);
1349}
1350EXPORT_SYMBOL(unregister_inetaddr_notifier);
1351
1352/* Rename ifa_labels for a device name change. Make some effort to preserve
1353 * existing alias numbering and to create unique labels if possible.
1354*/
1355static void inetdev_changename(struct net_device *dev, struct in_device *in_dev)
1356{
1357	struct in_ifaddr *ifa;
1358	int named = 0;
1359
1360	for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
1361		char old[IFNAMSIZ], *dot;
1362
1363		memcpy(old, ifa->ifa_label, IFNAMSIZ);
1364		memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
1365		if (named++ == 0)
1366			goto skip;
1367		dot = strchr(old, ':');
1368		if (!dot) {
1369			sprintf(old, ":%d", named);
1370			dot = old;
1371		}
1372		if (strlen(dot) + strlen(dev->name) < IFNAMSIZ)
1373			strcat(ifa->ifa_label, dot);
1374		else
1375			strcpy(ifa->ifa_label + (IFNAMSIZ - strlen(dot) - 1), dot);
1376skip:
1377		rtmsg_ifa(RTM_NEWADDR, ifa, NULL, 0);
1378	}
1379}
1380
1381static bool inetdev_valid_mtu(unsigned int mtu)
1382{
1383	return mtu >= 68;
1384}
1385
1386static void inetdev_send_gratuitous_arp(struct net_device *dev,
1387					struct in_device *in_dev)
1388
1389{
1390	struct in_ifaddr *ifa;
1391
1392	for (ifa = in_dev->ifa_list; ifa;
1393	     ifa = ifa->ifa_next) {
1394		arp_send(ARPOP_REQUEST, ETH_P_ARP,
1395			 ifa->ifa_local, dev,
1396			 ifa->ifa_local, NULL,
1397			 dev->dev_addr, NULL);
1398	}
1399}
1400
1401/* Called only under RTNL semaphore */
1402
1403static int inetdev_event(struct notifier_block *this, unsigned long event,
1404			 void *ptr)
1405{
1406	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1407	struct in_device *in_dev = __in_dev_get_rtnl(dev);
1408
1409	ASSERT_RTNL();
1410
1411	if (!in_dev) {
1412		if (event == NETDEV_REGISTER) {
1413			in_dev = inetdev_init(dev);
1414			if (IS_ERR(in_dev))
1415				return notifier_from_errno(PTR_ERR(in_dev));
1416			if (dev->flags & IFF_LOOPBACK) {
1417				IN_DEV_CONF_SET(in_dev, NOXFRM, 1);
1418				IN_DEV_CONF_SET(in_dev, NOPOLICY, 1);
1419			}
1420		} else if (event == NETDEV_CHANGEMTU) {
1421			/* Re-enabling IP */
1422			if (inetdev_valid_mtu(dev->mtu))
1423				in_dev = inetdev_init(dev);
1424		}
1425		goto out;
1426	}
1427
1428	switch (event) {
1429	case NETDEV_REGISTER:
1430		pr_debug("%s: bug\n", __func__);
1431		RCU_INIT_POINTER(dev->ip_ptr, NULL);
1432		break;
1433	case NETDEV_UP:
1434		if (!inetdev_valid_mtu(dev->mtu))
1435			break;
1436		if (dev->flags & IFF_LOOPBACK) {
1437			struct in_ifaddr *ifa = inet_alloc_ifa();
1438
1439			if (ifa) {
1440				INIT_HLIST_NODE(&ifa->hash);
1441				ifa->ifa_local =
1442				  ifa->ifa_address = htonl(INADDR_LOOPBACK);
1443				ifa->ifa_prefixlen = 8;
1444				ifa->ifa_mask = inet_make_mask(8);
1445				in_dev_hold(in_dev);
1446				ifa->ifa_dev = in_dev;
1447				ifa->ifa_scope = RT_SCOPE_HOST;
1448				memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
1449				set_ifa_lifetime(ifa, INFINITY_LIFE_TIME,
1450						 INFINITY_LIFE_TIME);
1451				ipv4_devconf_setall(in_dev);
1452				neigh_parms_data_state_setall(in_dev->arp_parms);
1453				inet_insert_ifa(ifa);
1454			}
1455		}
1456		ip_mc_up(in_dev);
1457		/* fall through */
1458	case NETDEV_CHANGEADDR:
1459		if (!IN_DEV_ARP_NOTIFY(in_dev))
1460			break;
1461		/* fall through */
1462	case NETDEV_NOTIFY_PEERS:
1463		/* Send gratuitous ARP to notify of link change */
1464		inetdev_send_gratuitous_arp(dev, in_dev);
1465		break;
1466	case NETDEV_DOWN:
1467		ip_mc_down(in_dev);
1468		break;
1469	case NETDEV_PRE_TYPE_CHANGE:
1470		ip_mc_unmap(in_dev);
1471		break;
1472	case NETDEV_POST_TYPE_CHANGE:
1473		ip_mc_remap(in_dev);
1474		break;
1475	case NETDEV_CHANGEMTU:
1476		if (inetdev_valid_mtu(dev->mtu))
1477			break;
1478		/* disable IP when MTU is not enough */
1479	case NETDEV_UNREGISTER:
1480		inetdev_destroy(in_dev);
1481		break;
1482	case NETDEV_CHANGENAME:
1483		/* Do not notify about label change, this event is
1484		 * not interesting to applications using netlink.
1485		 */
1486		inetdev_changename(dev, in_dev);
1487
1488		devinet_sysctl_unregister(in_dev);
1489		devinet_sysctl_register(in_dev);
1490		break;
1491	}
1492out:
1493	return NOTIFY_DONE;
1494}
1495
1496static struct notifier_block ip_netdev_notifier = {
1497	.notifier_call = inetdev_event,
1498};
1499
1500static size_t inet_nlmsg_size(void)
1501{
1502	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
1503	       + nla_total_size(4) /* IFA_ADDRESS */
1504	       + nla_total_size(4) /* IFA_LOCAL */
1505	       + nla_total_size(4) /* IFA_BROADCAST */
1506	       + nla_total_size(IFNAMSIZ) /* IFA_LABEL */
1507	       + nla_total_size(4)  /* IFA_FLAGS */
1508	       + nla_total_size(sizeof(struct ifa_cacheinfo)); /* IFA_CACHEINFO */
1509}
1510
1511static inline u32 cstamp_delta(unsigned long cstamp)
1512{
1513	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
1514}
1515
1516static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
1517			 unsigned long tstamp, u32 preferred, u32 valid)
1518{
1519	struct ifa_cacheinfo ci;
1520
1521	ci.cstamp = cstamp_delta(cstamp);
1522	ci.tstamp = cstamp_delta(tstamp);
1523	ci.ifa_prefered = preferred;
1524	ci.ifa_valid = valid;
1525
1526	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
1527}
1528
1529static int inet_fill_ifaddr(struct sk_buff *skb, struct in_ifaddr *ifa,
1530			    u32 portid, u32 seq, int event, unsigned int flags)
1531{
1532	struct ifaddrmsg *ifm;
1533	struct nlmsghdr  *nlh;
1534	u32 preferred, valid;
1535
1536	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*ifm), flags);
1537	if (!nlh)
1538		return -EMSGSIZE;
1539
1540	ifm = nlmsg_data(nlh);
1541	ifm->ifa_family = AF_INET;
1542	ifm->ifa_prefixlen = ifa->ifa_prefixlen;
1543	ifm->ifa_flags = ifa->ifa_flags;
1544	ifm->ifa_scope = ifa->ifa_scope;
1545	ifm->ifa_index = ifa->ifa_dev->dev->ifindex;
1546
1547	if (!(ifm->ifa_flags & IFA_F_PERMANENT)) {
1548		preferred = ifa->ifa_preferred_lft;
1549		valid = ifa->ifa_valid_lft;
1550		if (preferred != INFINITY_LIFE_TIME) {
1551			long tval = (jiffies - ifa->ifa_tstamp) / HZ;
1552
1553			if (preferred > tval)
1554				preferred -= tval;
1555			else
1556				preferred = 0;
1557			if (valid != INFINITY_LIFE_TIME) {
1558				if (valid > tval)
1559					valid -= tval;
1560				else
1561					valid = 0;
1562			}
1563		}
1564	} else {
1565		preferred = INFINITY_LIFE_TIME;
1566		valid = INFINITY_LIFE_TIME;
1567	}
1568	if ((ifa->ifa_address &&
1569	     nla_put_in_addr(skb, IFA_ADDRESS, ifa->ifa_address)) ||
1570	    (ifa->ifa_local &&
1571	     nla_put_in_addr(skb, IFA_LOCAL, ifa->ifa_local)) ||
1572	    (ifa->ifa_broadcast &&
1573	     nla_put_in_addr(skb, IFA_BROADCAST, ifa->ifa_broadcast)) ||
1574	    (ifa->ifa_label[0] &&
1575	     nla_put_string(skb, IFA_LABEL, ifa->ifa_label)) ||
1576	    nla_put_u32(skb, IFA_FLAGS, ifa->ifa_flags) ||
1577	    put_cacheinfo(skb, ifa->ifa_cstamp, ifa->ifa_tstamp,
1578			  preferred, valid))
1579		goto nla_put_failure;
1580
1581	nlmsg_end(skb, nlh);
1582	return 0;
1583
1584nla_put_failure:
1585	nlmsg_cancel(skb, nlh);
1586	return -EMSGSIZE;
1587}
1588
1589static int inet_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
1590{
1591	struct net *net = sock_net(skb->sk);
1592	int h, s_h;
1593	int idx, s_idx;
1594	int ip_idx, s_ip_idx;
1595	struct net_device *dev;
1596	struct in_device *in_dev;
1597	struct in_ifaddr *ifa;
1598	struct hlist_head *head;
 
1599
1600	s_h = cb->args[0];
1601	s_idx = idx = cb->args[1];
1602	s_ip_idx = ip_idx = cb->args[2];
1603
1604	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
1605		idx = 0;
1606		head = &net->dev_index_head[h];
1607		rcu_read_lock();
1608		cb->seq = atomic_read(&net->ipv4.dev_addr_genid) ^
1609			  net->dev_base_seq;
1610		hlist_for_each_entry_rcu(dev, head, index_hlist) {
1611			if (idx < s_idx)
1612				goto cont;
1613			if (h > s_h || idx > s_idx)
1614				s_ip_idx = 0;
1615			in_dev = __in_dev_get_rcu(dev);
1616			if (!in_dev)
1617				goto cont;
1618
1619			for (ifa = in_dev->ifa_list, ip_idx = 0; ifa;
1620			     ifa = ifa->ifa_next, ip_idx++) {
1621				if (ip_idx < s_ip_idx)
1622					continue;
1623				if (inet_fill_ifaddr(skb, ifa,
1624					     NETLINK_CB(cb->skb).portid,
1625					     cb->nlh->nlmsg_seq,
1626					     RTM_NEWADDR, NLM_F_MULTI) < 0) {
1627					rcu_read_unlock();
1628					goto done;
1629				}
1630				nl_dump_check_consistent(cb, nlmsg_hdr(skb));
1631			}
1632cont:
1633			idx++;
1634		}
1635		rcu_read_unlock();
1636	}
1637
1638done:
1639	cb->args[0] = h;
1640	cb->args[1] = idx;
1641	cb->args[2] = ip_idx;
1642
1643	return skb->len;
1644}
1645
1646static void rtmsg_ifa(int event, struct in_ifaddr *ifa, struct nlmsghdr *nlh,
1647		      u32 portid)
1648{
1649	struct sk_buff *skb;
1650	u32 seq = nlh ? nlh->nlmsg_seq : 0;
1651	int err = -ENOBUFS;
1652	struct net *net;
1653
1654	net = dev_net(ifa->ifa_dev->dev);
1655	skb = nlmsg_new(inet_nlmsg_size(), GFP_KERNEL);
1656	if (!skb)
1657		goto errout;
1658
1659	err = inet_fill_ifaddr(skb, ifa, portid, seq, event, 0);
1660	if (err < 0) {
1661		/* -EMSGSIZE implies BUG in inet_nlmsg_size() */
1662		WARN_ON(err == -EMSGSIZE);
1663		kfree_skb(skb);
1664		goto errout;
1665	}
1666	rtnl_notify(skb, net, portid, RTNLGRP_IPV4_IFADDR, nlh, GFP_KERNEL);
1667	return;
1668errout:
1669	if (err < 0)
1670		rtnl_set_sk_err(net, RTNLGRP_IPV4_IFADDR, err);
1671}
1672
1673static size_t inet_get_link_af_size(const struct net_device *dev,
1674				    u32 ext_filter_mask)
1675{
1676	struct in_device *in_dev = rcu_dereference_rtnl(dev->ip_ptr);
1677
1678	if (!in_dev)
1679		return 0;
1680
1681	return nla_total_size(IPV4_DEVCONF_MAX * 4); /* IFLA_INET_CONF */
1682}
1683
1684static int inet_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
1685			     u32 ext_filter_mask)
1686{
1687	struct in_device *in_dev = rcu_dereference_rtnl(dev->ip_ptr);
1688	struct nlattr *nla;
1689	int i;
1690
1691	if (!in_dev)
1692		return -ENODATA;
1693
1694	nla = nla_reserve(skb, IFLA_INET_CONF, IPV4_DEVCONF_MAX * 4);
1695	if (!nla)
1696		return -EMSGSIZE;
1697
1698	for (i = 0; i < IPV4_DEVCONF_MAX; i++)
1699		((u32 *) nla_data(nla))[i] = in_dev->cnf.data[i];
1700
1701	return 0;
1702}
1703
1704static const struct nla_policy inet_af_policy[IFLA_INET_MAX+1] = {
1705	[IFLA_INET_CONF]	= { .type = NLA_NESTED },
1706};
1707
1708static int inet_validate_link_af(const struct net_device *dev,
1709				 const struct nlattr *nla)
1710{
1711	struct nlattr *a, *tb[IFLA_INET_MAX+1];
1712	int err, rem;
1713
1714	if (dev && !__in_dev_get_rtnl(dev))
1715		return -EAFNOSUPPORT;
1716
1717	err = nla_parse_nested(tb, IFLA_INET_MAX, nla, inet_af_policy);
1718	if (err < 0)
1719		return err;
1720
1721	if (tb[IFLA_INET_CONF]) {
1722		nla_for_each_nested(a, tb[IFLA_INET_CONF], rem) {
1723			int cfgid = nla_type(a);
1724
1725			if (nla_len(a) < 4)
1726				return -EINVAL;
1727
1728			if (cfgid <= 0 || cfgid > IPV4_DEVCONF_MAX)
1729				return -EINVAL;
1730		}
1731	}
1732
1733	return 0;
1734}
1735
1736static int inet_set_link_af(struct net_device *dev, const struct nlattr *nla)
1737{
1738	struct in_device *in_dev = __in_dev_get_rtnl(dev);
1739	struct nlattr *a, *tb[IFLA_INET_MAX+1];
1740	int rem;
1741
1742	if (!in_dev)
1743		return -EAFNOSUPPORT;
1744
1745	if (nla_parse_nested(tb, IFLA_INET_MAX, nla, NULL) < 0)
1746		BUG();
1747
1748	if (tb[IFLA_INET_CONF]) {
1749		nla_for_each_nested(a, tb[IFLA_INET_CONF], rem)
1750			ipv4_devconf_set(in_dev, nla_type(a), nla_get_u32(a));
1751	}
1752
1753	return 0;
1754}
1755
1756static int inet_netconf_msgsize_devconf(int type)
1757{
1758	int size = NLMSG_ALIGN(sizeof(struct netconfmsg))
1759		   + nla_total_size(4);	/* NETCONFA_IFINDEX */
1760	bool all = false;
1761
1762	if (type == NETCONFA_ALL)
1763		all = true;
1764
1765	if (all || type == NETCONFA_FORWARDING)
1766		size += nla_total_size(4);
1767	if (all || type == NETCONFA_RP_FILTER)
1768		size += nla_total_size(4);
1769	if (all || type == NETCONFA_MC_FORWARDING)
1770		size += nla_total_size(4);
1771	if (all || type == NETCONFA_PROXY_NEIGH)
1772		size += nla_total_size(4);
1773	if (all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN)
1774		size += nla_total_size(4);
1775
1776	return size;
1777}
1778
1779static int inet_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
1780				     struct ipv4_devconf *devconf, u32 portid,
1781				     u32 seq, int event, unsigned int flags,
1782				     int type)
1783{
1784	struct nlmsghdr  *nlh;
1785	struct netconfmsg *ncm;
1786	bool all = false;
1787
1788	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
1789			flags);
1790	if (!nlh)
1791		return -EMSGSIZE;
1792
1793	if (type == NETCONFA_ALL)
1794		all = true;
1795
1796	ncm = nlmsg_data(nlh);
1797	ncm->ncm_family = AF_INET;
1798
1799	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
1800		goto nla_put_failure;
1801
1802	if ((all || type == NETCONFA_FORWARDING) &&
1803	    nla_put_s32(skb, NETCONFA_FORWARDING,
1804			IPV4_DEVCONF(*devconf, FORWARDING)) < 0)
1805		goto nla_put_failure;
1806	if ((all || type == NETCONFA_RP_FILTER) &&
1807	    nla_put_s32(skb, NETCONFA_RP_FILTER,
1808			IPV4_DEVCONF(*devconf, RP_FILTER)) < 0)
1809		goto nla_put_failure;
1810	if ((all || type == NETCONFA_MC_FORWARDING) &&
1811	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
1812			IPV4_DEVCONF(*devconf, MC_FORWARDING)) < 0)
1813		goto nla_put_failure;
1814	if ((all || type == NETCONFA_PROXY_NEIGH) &&
1815	    nla_put_s32(skb, NETCONFA_PROXY_NEIGH,
1816			IPV4_DEVCONF(*devconf, PROXY_ARP)) < 0)
1817		goto nla_put_failure;
1818	if ((all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) &&
1819	    nla_put_s32(skb, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
1820			IPV4_DEVCONF(*devconf, IGNORE_ROUTES_WITH_LINKDOWN)) < 0)
1821		goto nla_put_failure;
1822
1823	nlmsg_end(skb, nlh);
1824	return 0;
1825
1826nla_put_failure:
1827	nlmsg_cancel(skb, nlh);
1828	return -EMSGSIZE;
1829}
1830
1831void inet_netconf_notify_devconf(struct net *net, int type, int ifindex,
1832				 struct ipv4_devconf *devconf)
1833{
1834	struct sk_buff *skb;
1835	int err = -ENOBUFS;
1836
1837	skb = nlmsg_new(inet_netconf_msgsize_devconf(type), GFP_ATOMIC);
1838	if (!skb)
1839		goto errout;
1840
1841	err = inet_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
1842					RTM_NEWNETCONF, 0, type);
1843	if (err < 0) {
1844		/* -EMSGSIZE implies BUG in inet_netconf_msgsize_devconf() */
1845		WARN_ON(err == -EMSGSIZE);
1846		kfree_skb(skb);
1847		goto errout;
1848	}
1849	rtnl_notify(skb, net, 0, RTNLGRP_IPV4_NETCONF, NULL, GFP_ATOMIC);
1850	return;
1851errout:
1852	if (err < 0)
1853		rtnl_set_sk_err(net, RTNLGRP_IPV4_NETCONF, err);
1854}
1855
1856static const struct nla_policy devconf_ipv4_policy[NETCONFA_MAX+1] = {
1857	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
1858	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
1859	[NETCONFA_RP_FILTER]	= { .len = sizeof(int) },
1860	[NETCONFA_PROXY_NEIGH]	= { .len = sizeof(int) },
1861	[NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN]	= { .len = sizeof(int) },
1862};
1863
1864static int inet_netconf_get_devconf(struct sk_buff *in_skb,
1865				    struct nlmsghdr *nlh)
1866{
1867	struct net *net = sock_net(in_skb->sk);
1868	struct nlattr *tb[NETCONFA_MAX+1];
1869	struct netconfmsg *ncm;
1870	struct sk_buff *skb;
1871	struct ipv4_devconf *devconf;
1872	struct in_device *in_dev;
1873	struct net_device *dev;
1874	int ifindex;
1875	int err;
1876
1877	err = nlmsg_parse(nlh, sizeof(*ncm), tb, NETCONFA_MAX,
1878			  devconf_ipv4_policy);
1879	if (err < 0)
1880		goto errout;
1881
1882	err = -EINVAL;
1883	if (!tb[NETCONFA_IFINDEX])
1884		goto errout;
1885
1886	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
1887	switch (ifindex) {
1888	case NETCONFA_IFINDEX_ALL:
1889		devconf = net->ipv4.devconf_all;
1890		break;
1891	case NETCONFA_IFINDEX_DEFAULT:
1892		devconf = net->ipv4.devconf_dflt;
1893		break;
1894	default:
1895		dev = __dev_get_by_index(net, ifindex);
1896		if (!dev)
1897			goto errout;
1898		in_dev = __in_dev_get_rtnl(dev);
1899		if (!in_dev)
1900			goto errout;
1901		devconf = &in_dev->cnf;
1902		break;
1903	}
1904
1905	err = -ENOBUFS;
1906	skb = nlmsg_new(inet_netconf_msgsize_devconf(NETCONFA_ALL), GFP_ATOMIC);
1907	if (!skb)
1908		goto errout;
1909
1910	err = inet_netconf_fill_devconf(skb, ifindex, devconf,
1911					NETLINK_CB(in_skb).portid,
1912					nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
1913					NETCONFA_ALL);
1914	if (err < 0) {
1915		/* -EMSGSIZE implies BUG in inet_netconf_msgsize_devconf() */
1916		WARN_ON(err == -EMSGSIZE);
1917		kfree_skb(skb);
1918		goto errout;
1919	}
1920	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
1921errout:
1922	return err;
1923}
1924
1925static int inet_netconf_dump_devconf(struct sk_buff *skb,
1926				     struct netlink_callback *cb)
1927{
1928	struct net *net = sock_net(skb->sk);
1929	int h, s_h;
1930	int idx, s_idx;
1931	struct net_device *dev;
1932	struct in_device *in_dev;
1933	struct hlist_head *head;
1934
1935	s_h = cb->args[0];
1936	s_idx = idx = cb->args[1];
1937
1938	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
1939		idx = 0;
1940		head = &net->dev_index_head[h];
1941		rcu_read_lock();
1942		cb->seq = atomic_read(&net->ipv4.dev_addr_genid) ^
1943			  net->dev_base_seq;
1944		hlist_for_each_entry_rcu(dev, head, index_hlist) {
1945			if (idx < s_idx)
1946				goto cont;
1947			in_dev = __in_dev_get_rcu(dev);
1948			if (!in_dev)
1949				goto cont;
1950
1951			if (inet_netconf_fill_devconf(skb, dev->ifindex,
1952						      &in_dev->cnf,
1953						      NETLINK_CB(cb->skb).portid,
1954						      cb->nlh->nlmsg_seq,
1955						      RTM_NEWNETCONF,
1956						      NLM_F_MULTI,
1957						      NETCONFA_ALL) < 0) {
1958				rcu_read_unlock();
1959				goto done;
1960			}
1961			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
1962cont:
1963			idx++;
1964		}
1965		rcu_read_unlock();
1966	}
1967	if (h == NETDEV_HASHENTRIES) {
1968		if (inet_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
1969					      net->ipv4.devconf_all,
1970					      NETLINK_CB(cb->skb).portid,
1971					      cb->nlh->nlmsg_seq,
1972					      RTM_NEWNETCONF, NLM_F_MULTI,
1973					      NETCONFA_ALL) < 0)
1974			goto done;
1975		else
1976			h++;
1977	}
1978	if (h == NETDEV_HASHENTRIES + 1) {
1979		if (inet_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
1980					      net->ipv4.devconf_dflt,
1981					      NETLINK_CB(cb->skb).portid,
1982					      cb->nlh->nlmsg_seq,
1983					      RTM_NEWNETCONF, NLM_F_MULTI,
1984					      NETCONFA_ALL) < 0)
1985			goto done;
1986		else
1987			h++;
1988	}
1989done:
1990	cb->args[0] = h;
1991	cb->args[1] = idx;
1992
1993	return skb->len;
1994}
1995
1996#ifdef CONFIG_SYSCTL
1997
1998static void devinet_copy_dflt_conf(struct net *net, int i)
1999{
2000	struct net_device *dev;
2001
2002	rcu_read_lock();
2003	for_each_netdev_rcu(net, dev) {
2004		struct in_device *in_dev;
2005
2006		in_dev = __in_dev_get_rcu(dev);
2007		if (in_dev && !test_bit(i, in_dev->cnf.state))
2008			in_dev->cnf.data[i] = net->ipv4.devconf_dflt->data[i];
2009	}
2010	rcu_read_unlock();
2011}
2012
2013/* called with RTNL locked */
2014static void inet_forward_change(struct net *net)
2015{
2016	struct net_device *dev;
2017	int on = IPV4_DEVCONF_ALL(net, FORWARDING);
2018
2019	IPV4_DEVCONF_ALL(net, ACCEPT_REDIRECTS) = !on;
2020	IPV4_DEVCONF_DFLT(net, FORWARDING) = on;
2021	inet_netconf_notify_devconf(net, NETCONFA_FORWARDING,
2022				    NETCONFA_IFINDEX_ALL,
2023				    net->ipv4.devconf_all);
2024	inet_netconf_notify_devconf(net, NETCONFA_FORWARDING,
2025				    NETCONFA_IFINDEX_DEFAULT,
2026				    net->ipv4.devconf_dflt);
2027
2028	for_each_netdev(net, dev) {
2029		struct in_device *in_dev;
2030		if (on)
2031			dev_disable_lro(dev);
2032		rcu_read_lock();
2033		in_dev = __in_dev_get_rcu(dev);
2034		if (in_dev) {
2035			IN_DEV_CONF_SET(in_dev, FORWARDING, on);
2036			inet_netconf_notify_devconf(net, NETCONFA_FORWARDING,
2037						    dev->ifindex, &in_dev->cnf);
2038		}
2039		rcu_read_unlock();
2040	}
2041}
2042
2043static int devinet_conf_ifindex(struct net *net, struct ipv4_devconf *cnf)
2044{
2045	if (cnf == net->ipv4.devconf_dflt)
2046		return NETCONFA_IFINDEX_DEFAULT;
2047	else if (cnf == net->ipv4.devconf_all)
2048		return NETCONFA_IFINDEX_ALL;
2049	else {
2050		struct in_device *idev
2051			= container_of(cnf, struct in_device, cnf);
2052		return idev->dev->ifindex;
2053	}
2054}
2055
2056static int devinet_conf_proc(struct ctl_table *ctl, int write,
2057			     void __user *buffer,
2058			     size_t *lenp, loff_t *ppos)
2059{
2060	int old_value = *(int *)ctl->data;
2061	int ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
2062	int new_value = *(int *)ctl->data;
2063
2064	if (write) {
2065		struct ipv4_devconf *cnf = ctl->extra1;
2066		struct net *net = ctl->extra2;
2067		int i = (int *)ctl->data - cnf->data;
2068		int ifindex;
2069
2070		set_bit(i, cnf->state);
2071
2072		if (cnf == net->ipv4.devconf_dflt)
2073			devinet_copy_dflt_conf(net, i);
2074		if (i == IPV4_DEVCONF_ACCEPT_LOCAL - 1 ||
2075		    i == IPV4_DEVCONF_ROUTE_LOCALNET - 1)
2076			if ((new_value == 0) && (old_value != 0))
2077				rt_cache_flush(net);
2078
2079		if (i == IPV4_DEVCONF_RP_FILTER - 1 &&
2080		    new_value != old_value) {
2081			ifindex = devinet_conf_ifindex(net, cnf);
2082			inet_netconf_notify_devconf(net, NETCONFA_RP_FILTER,
2083						    ifindex, cnf);
2084		}
2085		if (i == IPV4_DEVCONF_PROXY_ARP - 1 &&
2086		    new_value != old_value) {
2087			ifindex = devinet_conf_ifindex(net, cnf);
2088			inet_netconf_notify_devconf(net, NETCONFA_PROXY_NEIGH,
2089						    ifindex, cnf);
2090		}
2091		if (i == IPV4_DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN - 1 &&
2092		    new_value != old_value) {
2093			ifindex = devinet_conf_ifindex(net, cnf);
2094			inet_netconf_notify_devconf(net, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
2095						    ifindex, cnf);
2096		}
2097	}
2098
2099	return ret;
2100}
2101
2102static int devinet_sysctl_forward(struct ctl_table *ctl, int write,
2103				  void __user *buffer,
2104				  size_t *lenp, loff_t *ppos)
2105{
2106	int *valp = ctl->data;
2107	int val = *valp;
2108	loff_t pos = *ppos;
2109	int ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
2110
2111	if (write && *valp != val) {
2112		struct net *net = ctl->extra2;
2113
2114		if (valp != &IPV4_DEVCONF_DFLT(net, FORWARDING)) {
2115			if (!rtnl_trylock()) {
2116				/* Restore the original values before restarting */
2117				*valp = val;
2118				*ppos = pos;
2119				return restart_syscall();
2120			}
2121			if (valp == &IPV4_DEVCONF_ALL(net, FORWARDING)) {
2122				inet_forward_change(net);
2123			} else {
2124				struct ipv4_devconf *cnf = ctl->extra1;
2125				struct in_device *idev =
2126					container_of(cnf, struct in_device, cnf);
2127				if (*valp)
2128					dev_disable_lro(idev->dev);
2129				inet_netconf_notify_devconf(net,
2130							    NETCONFA_FORWARDING,
2131							    idev->dev->ifindex,
2132							    cnf);
2133			}
2134			rtnl_unlock();
2135			rt_cache_flush(net);
2136		} else
2137			inet_netconf_notify_devconf(net, NETCONFA_FORWARDING,
2138						    NETCONFA_IFINDEX_DEFAULT,
2139						    net->ipv4.devconf_dflt);
2140	}
2141
2142	return ret;
2143}
2144
2145static int ipv4_doint_and_flush(struct ctl_table *ctl, int write,
2146				void __user *buffer,
2147				size_t *lenp, loff_t *ppos)
2148{
2149	int *valp = ctl->data;
2150	int val = *valp;
2151	int ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
2152	struct net *net = ctl->extra2;
2153
2154	if (write && *valp != val)
2155		rt_cache_flush(net);
2156
2157	return ret;
2158}
2159
2160#define DEVINET_SYSCTL_ENTRY(attr, name, mval, proc) \
2161	{ \
2162		.procname	= name, \
2163		.data		= ipv4_devconf.data + \
2164				  IPV4_DEVCONF_ ## attr - 1, \
2165		.maxlen		= sizeof(int), \
2166		.mode		= mval, \
2167		.proc_handler	= proc, \
2168		.extra1		= &ipv4_devconf, \
2169	}
2170
2171#define DEVINET_SYSCTL_RW_ENTRY(attr, name) \
2172	DEVINET_SYSCTL_ENTRY(attr, name, 0644, devinet_conf_proc)
2173
2174#define DEVINET_SYSCTL_RO_ENTRY(attr, name) \
2175	DEVINET_SYSCTL_ENTRY(attr, name, 0444, devinet_conf_proc)
2176
2177#define DEVINET_SYSCTL_COMPLEX_ENTRY(attr, name, proc) \
2178	DEVINET_SYSCTL_ENTRY(attr, name, 0644, proc)
2179
2180#define DEVINET_SYSCTL_FLUSHING_ENTRY(attr, name) \
2181	DEVINET_SYSCTL_COMPLEX_ENTRY(attr, name, ipv4_doint_and_flush)
2182
2183static struct devinet_sysctl_table {
2184	struct ctl_table_header *sysctl_header;
2185	struct ctl_table devinet_vars[__IPV4_DEVCONF_MAX];
2186} devinet_sysctl = {
2187	.devinet_vars = {
2188		DEVINET_SYSCTL_COMPLEX_ENTRY(FORWARDING, "forwarding",
2189					     devinet_sysctl_forward),
2190		DEVINET_SYSCTL_RO_ENTRY(MC_FORWARDING, "mc_forwarding"),
2191
2192		DEVINET_SYSCTL_RW_ENTRY(ACCEPT_REDIRECTS, "accept_redirects"),
2193		DEVINET_SYSCTL_RW_ENTRY(SECURE_REDIRECTS, "secure_redirects"),
2194		DEVINET_SYSCTL_RW_ENTRY(SHARED_MEDIA, "shared_media"),
2195		DEVINET_SYSCTL_RW_ENTRY(RP_FILTER, "rp_filter"),
2196		DEVINET_SYSCTL_RW_ENTRY(SEND_REDIRECTS, "send_redirects"),
2197		DEVINET_SYSCTL_RW_ENTRY(ACCEPT_SOURCE_ROUTE,
2198					"accept_source_route"),
2199		DEVINET_SYSCTL_RW_ENTRY(ACCEPT_LOCAL, "accept_local"),
2200		DEVINET_SYSCTL_RW_ENTRY(SRC_VMARK, "src_valid_mark"),
2201		DEVINET_SYSCTL_RW_ENTRY(PROXY_ARP, "proxy_arp"),
2202		DEVINET_SYSCTL_RW_ENTRY(MEDIUM_ID, "medium_id"),
2203		DEVINET_SYSCTL_RW_ENTRY(BOOTP_RELAY, "bootp_relay"),
2204		DEVINET_SYSCTL_RW_ENTRY(LOG_MARTIANS, "log_martians"),
2205		DEVINET_SYSCTL_RW_ENTRY(TAG, "tag"),
2206		DEVINET_SYSCTL_RW_ENTRY(ARPFILTER, "arp_filter"),
2207		DEVINET_SYSCTL_RW_ENTRY(ARP_ANNOUNCE, "arp_announce"),
2208		DEVINET_SYSCTL_RW_ENTRY(ARP_IGNORE, "arp_ignore"),
2209		DEVINET_SYSCTL_RW_ENTRY(ARP_ACCEPT, "arp_accept"),
2210		DEVINET_SYSCTL_RW_ENTRY(ARP_NOTIFY, "arp_notify"),
2211		DEVINET_SYSCTL_RW_ENTRY(PROXY_ARP_PVLAN, "proxy_arp_pvlan"),
2212		DEVINET_SYSCTL_RW_ENTRY(FORCE_IGMP_VERSION,
2213					"force_igmp_version"),
2214		DEVINET_SYSCTL_RW_ENTRY(IGMPV2_UNSOLICITED_REPORT_INTERVAL,
2215					"igmpv2_unsolicited_report_interval"),
2216		DEVINET_SYSCTL_RW_ENTRY(IGMPV3_UNSOLICITED_REPORT_INTERVAL,
2217					"igmpv3_unsolicited_report_interval"),
2218		DEVINET_SYSCTL_RW_ENTRY(IGNORE_ROUTES_WITH_LINKDOWN,
2219					"ignore_routes_with_linkdown"),
2220		DEVINET_SYSCTL_RW_ENTRY(DROP_GRATUITOUS_ARP,
2221					"drop_gratuitous_arp"),
2222
2223		DEVINET_SYSCTL_FLUSHING_ENTRY(NOXFRM, "disable_xfrm"),
2224		DEVINET_SYSCTL_FLUSHING_ENTRY(NOPOLICY, "disable_policy"),
 
 
2225		DEVINET_SYSCTL_FLUSHING_ENTRY(PROMOTE_SECONDARIES,
2226					      "promote_secondaries"),
2227		DEVINET_SYSCTL_FLUSHING_ENTRY(ROUTE_LOCALNET,
2228					      "route_localnet"),
2229		DEVINET_SYSCTL_FLUSHING_ENTRY(DROP_UNICAST_IN_L2_MULTICAST,
2230					      "drop_unicast_in_l2_multicast"),
2231	},
2232};
2233
2234static int __devinet_sysctl_register(struct net *net, char *dev_name,
2235					struct ipv4_devconf *p)
2236{
2237	int i;
2238	struct devinet_sysctl_table *t;
2239	char path[sizeof("net/ipv4/conf/") + IFNAMSIZ];
2240
2241	t = kmemdup(&devinet_sysctl, sizeof(*t), GFP_KERNEL);
2242	if (!t)
2243		goto out;
2244
2245	for (i = 0; i < ARRAY_SIZE(t->devinet_vars) - 1; i++) {
2246		t->devinet_vars[i].data += (char *)p - (char *)&ipv4_devconf;
2247		t->devinet_vars[i].extra1 = p;
2248		t->devinet_vars[i].extra2 = net;
2249	}
2250
2251	snprintf(path, sizeof(path), "net/ipv4/conf/%s", dev_name);
2252
2253	t->sysctl_header = register_net_sysctl(net, path, t->devinet_vars);
2254	if (!t->sysctl_header)
2255		goto free;
2256
2257	p->sysctl = t;
2258	return 0;
2259
2260free:
2261	kfree(t);
2262out:
2263	return -ENOBUFS;
2264}
2265
2266static void __devinet_sysctl_unregister(struct ipv4_devconf *cnf)
2267{
2268	struct devinet_sysctl_table *t = cnf->sysctl;
2269
2270	if (!t)
2271		return;
2272
2273	cnf->sysctl = NULL;
2274	unregister_net_sysctl_table(t->sysctl_header);
2275	kfree(t);
2276}
2277
2278static int devinet_sysctl_register(struct in_device *idev)
2279{
2280	int err;
2281
2282	if (!sysctl_dev_name_is_allowed(idev->dev->name))
2283		return -EINVAL;
2284
2285	err = neigh_sysctl_register(idev->dev, idev->arp_parms, NULL);
2286	if (err)
2287		return err;
2288	err = __devinet_sysctl_register(dev_net(idev->dev), idev->dev->name,
2289					&idev->cnf);
2290	if (err)
2291		neigh_sysctl_unregister(idev->arp_parms);
2292	return err;
2293}
2294
2295static void devinet_sysctl_unregister(struct in_device *idev)
2296{
2297	__devinet_sysctl_unregister(&idev->cnf);
2298	neigh_sysctl_unregister(idev->arp_parms);
2299}
2300
2301static struct ctl_table ctl_forward_entry[] = {
2302	{
2303		.procname	= "ip_forward",
2304		.data		= &ipv4_devconf.data[
2305					IPV4_DEVCONF_FORWARDING - 1],
2306		.maxlen		= sizeof(int),
2307		.mode		= 0644,
2308		.proc_handler	= devinet_sysctl_forward,
2309		.extra1		= &ipv4_devconf,
2310		.extra2		= &init_net,
2311	},
2312	{ },
2313};
2314#endif
2315
2316static __net_init int devinet_init_net(struct net *net)
2317{
2318	int err;
2319	struct ipv4_devconf *all, *dflt;
2320#ifdef CONFIG_SYSCTL
2321	struct ctl_table *tbl = ctl_forward_entry;
2322	struct ctl_table_header *forw_hdr;
2323#endif
2324
2325	err = -ENOMEM;
2326	all = &ipv4_devconf;
2327	dflt = &ipv4_devconf_dflt;
2328
2329	if (!net_eq(net, &init_net)) {
2330		all = kmemdup(all, sizeof(ipv4_devconf), GFP_KERNEL);
2331		if (!all)
2332			goto err_alloc_all;
2333
2334		dflt = kmemdup(dflt, sizeof(ipv4_devconf_dflt), GFP_KERNEL);
2335		if (!dflt)
2336			goto err_alloc_dflt;
2337
2338#ifdef CONFIG_SYSCTL
2339		tbl = kmemdup(tbl, sizeof(ctl_forward_entry), GFP_KERNEL);
2340		if (!tbl)
2341			goto err_alloc_ctl;
2342
2343		tbl[0].data = &all->data[IPV4_DEVCONF_FORWARDING - 1];
2344		tbl[0].extra1 = all;
2345		tbl[0].extra2 = net;
2346#endif
2347	}
2348
2349#ifdef CONFIG_SYSCTL
2350	err = __devinet_sysctl_register(net, "all", all);
2351	if (err < 0)
2352		goto err_reg_all;
2353
2354	err = __devinet_sysctl_register(net, "default", dflt);
2355	if (err < 0)
2356		goto err_reg_dflt;
2357
2358	err = -ENOMEM;
2359	forw_hdr = register_net_sysctl(net, "net/ipv4", tbl);
2360	if (!forw_hdr)
2361		goto err_reg_ctl;
2362	net->ipv4.forw_hdr = forw_hdr;
2363#endif
2364
2365	net->ipv4.devconf_all = all;
2366	net->ipv4.devconf_dflt = dflt;
2367	return 0;
2368
2369#ifdef CONFIG_SYSCTL
2370err_reg_ctl:
2371	__devinet_sysctl_unregister(dflt);
2372err_reg_dflt:
2373	__devinet_sysctl_unregister(all);
2374err_reg_all:
2375	if (tbl != ctl_forward_entry)
2376		kfree(tbl);
2377err_alloc_ctl:
2378#endif
2379	if (dflt != &ipv4_devconf_dflt)
2380		kfree(dflt);
2381err_alloc_dflt:
2382	if (all != &ipv4_devconf)
2383		kfree(all);
2384err_alloc_all:
2385	return err;
2386}
2387
2388static __net_exit void devinet_exit_net(struct net *net)
2389{
2390#ifdef CONFIG_SYSCTL
2391	struct ctl_table *tbl;
2392
2393	tbl = net->ipv4.forw_hdr->ctl_table_arg;
2394	unregister_net_sysctl_table(net->ipv4.forw_hdr);
2395	__devinet_sysctl_unregister(net->ipv4.devconf_dflt);
2396	__devinet_sysctl_unregister(net->ipv4.devconf_all);
2397	kfree(tbl);
2398#endif
2399	kfree(net->ipv4.devconf_dflt);
2400	kfree(net->ipv4.devconf_all);
2401}
2402
2403static __net_initdata struct pernet_operations devinet_ops = {
2404	.init = devinet_init_net,
2405	.exit = devinet_exit_net,
2406};
2407
2408static struct rtnl_af_ops inet_af_ops __read_mostly = {
2409	.family		  = AF_INET,
2410	.fill_link_af	  = inet_fill_link_af,
2411	.get_link_af_size = inet_get_link_af_size,
2412	.validate_link_af = inet_validate_link_af,
2413	.set_link_af	  = inet_set_link_af,
2414};
2415
2416void __init devinet_init(void)
2417{
2418	int i;
2419
2420	for (i = 0; i < IN4_ADDR_HSIZE; i++)
2421		INIT_HLIST_HEAD(&inet_addr_lst[i]);
2422
2423	register_pernet_subsys(&devinet_ops);
2424
2425	register_gifconf(PF_INET, inet_gifconf);
2426	register_netdevice_notifier(&ip_netdev_notifier);
2427
2428	queue_delayed_work(system_power_efficient_wq, &check_lifetime_work, 0);
2429
2430	rtnl_af_register(&inet_af_ops);
2431
2432	rtnl_register(PF_INET, RTM_NEWADDR, inet_rtm_newaddr, NULL, NULL);
2433	rtnl_register(PF_INET, RTM_DELADDR, inet_rtm_deladdr, NULL, NULL);
2434	rtnl_register(PF_INET, RTM_GETADDR, NULL, inet_dump_ifaddr, NULL);
2435	rtnl_register(PF_INET, RTM_GETNETCONF, inet_netconf_get_devconf,
2436		      inet_netconf_dump_devconf, NULL);
2437}