xref: /linux/net/ipv6/addrconf.c (revision be54f8c558027a218423134dd9b8c7c46d92204a)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *	IPv6 Address [auto]configuration
4  *	Linux INET6 implementation
5  *
6  *	Authors:
7  *	Pedro Roque		<roque@di.fc.ul.pt>
8  *	Alexey Kuznetsov	<kuznet@ms2.inr.ac.ru>
9  */
10 
11 /*
12  *	Changes:
13  *
14  *	Janos Farkas			:	delete timer on ifdown
15  *	<chexum@bankinf.banki.hu>
16  *	Andi Kleen			:	kill double kfree on module
17  *						unload.
18  *	Maciej W. Rozycki		:	FDDI support
19  *	sekiya@USAGI			:	Don't send too many RS
20  *						packets.
21  *	yoshfuji@USAGI			:       Fixed interval between DAD
22  *						packets.
23  *	YOSHIFUJI Hideaki @USAGI	:	improved accuracy of
24  *						address validation timer.
25  *	YOSHIFUJI Hideaki @USAGI	:	Privacy Extensions (RFC3041)
26  *						support.
27  *	Yuji SEKIYA @USAGI		:	Don't assign a same IPv6
28  *						address on a same interface.
29  *	YOSHIFUJI Hideaki @USAGI	:	ARCnet support
30  *	YOSHIFUJI Hideaki @USAGI	:	convert /proc/net/if_inet6 to
31  *						seq_file.
32  *	YOSHIFUJI Hideaki @USAGI	:	improved source address
33  *						selection; consider scope,
34  *						status etc.
35  */
36 
37 #define pr_fmt(fmt) "IPv6: " fmt
38 
39 #include <linux/errno.h>
40 #include <linux/types.h>
41 #include <linux/kernel.h>
42 #include <linux/sched/signal.h>
43 #include <linux/socket.h>
44 #include <linux/sockios.h>
45 #include <linux/net.h>
46 #include <linux/inet.h>
47 #include <linux/in6.h>
48 #include <linux/netdevice.h>
49 #include <linux/if_addr.h>
50 #include <linux/if_arp.h>
51 #include <linux/if_arcnet.h>
52 #include <linux/if_infiniband.h>
53 #include <linux/route.h>
54 #include <linux/inetdevice.h>
55 #include <linux/init.h>
56 #include <linux/slab.h>
57 #ifdef CONFIG_SYSCTL
58 #include <linux/sysctl.h>
59 #endif
60 #include <linux/capability.h>
61 #include <linux/delay.h>
62 #include <linux/notifier.h>
63 #include <linux/string.h>
64 #include <linux/hash.h>
65 
66 #include <net/ip_tunnels.h>
67 #include <net/net_namespace.h>
68 #include <net/sock.h>
69 #include <net/snmp.h>
70 
71 #include <net/6lowpan.h>
72 #include <net/firewire.h>
73 #include <net/ipv6.h>
74 #include <net/protocol.h>
75 #include <net/ndisc.h>
76 #include <net/ip6_route.h>
77 #include <net/addrconf.h>
78 #include <net/tcp.h>
79 #include <net/ip.h>
80 #include <net/netlink.h>
81 #include <net/pkt_sched.h>
82 #include <net/l3mdev.h>
83 #include <net/netdev_lock.h>
84 #include <linux/if_tunnel.h>
85 #include <linux/rtnetlink.h>
86 #include <linux/netconf.h>
87 #include <linux/random.h>
88 #include <linux/uaccess.h>
89 #include <linux/unaligned.h>
90 
91 #include <linux/proc_fs.h>
92 #include <linux/seq_file.h>
93 #include <linux/export.h>
94 #include <linux/ioam6.h>
95 
96 #define IPV6_MAX_STRLEN \
97 	sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")
98 
cstamp_delta(unsigned long cstamp)99 static inline u32 cstamp_delta(unsigned long cstamp)
100 {
101 	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
102 }
103 
rfc3315_s14_backoff_init(s32 irt)104 static inline s32 rfc3315_s14_backoff_init(s32 irt)
105 {
106 	/* multiply 'initial retransmission time' by 0.9 .. 1.1 */
107 	u64 tmp = get_random_u32_inclusive(900000, 1100000) * (u64)irt;
108 	do_div(tmp, 1000000);
109 	return (s32)tmp;
110 }
111 
rfc3315_s14_backoff_update(s32 rt,s32 mrt)112 static inline s32 rfc3315_s14_backoff_update(s32 rt, s32 mrt)
113 {
114 	/* multiply 'retransmission timeout' by 1.9 .. 2.1 */
115 	u64 tmp = get_random_u32_inclusive(1900000, 2100000) * (u64)rt;
116 	do_div(tmp, 1000000);
117 	if ((s32)tmp > mrt) {
118 		/* multiply 'maximum retransmission time' by 0.9 .. 1.1 */
119 		tmp = get_random_u32_inclusive(900000, 1100000) * (u64)mrt;
120 		do_div(tmp, 1000000);
121 	}
122 	return (s32)tmp;
123 }
124 
125 #ifdef CONFIG_SYSCTL
126 static int addrconf_sysctl_register(struct inet6_dev *idev);
127 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
128 #else
addrconf_sysctl_register(struct inet6_dev * idev)129 static inline int addrconf_sysctl_register(struct inet6_dev *idev)
130 {
131 	return 0;
132 }
133 
addrconf_sysctl_unregister(struct inet6_dev * idev)134 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
135 {
136 }
137 #endif
138 
139 static void ipv6_gen_rnd_iid(struct in6_addr *addr);
140 
141 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
142 static int ipv6_count_addresses(const struct inet6_dev *idev);
143 static int ipv6_generate_stable_address(struct in6_addr *addr,
144 					u8 dad_count,
145 					const struct inet6_dev *idev);
146 
147 #define IN6_ADDR_HSIZE_SHIFT	8
148 #define IN6_ADDR_HSIZE		(1 << IN6_ADDR_HSIZE_SHIFT)
149 
150 static void addrconf_verify(struct net *net);
151 static void addrconf_verify_rtnl(struct net *net);
152 
153 static struct workqueue_struct *addrconf_wq;
154 
155 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
156 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
157 
158 static void addrconf_type_change(struct net_device *dev,
159 				 unsigned long event);
160 static int addrconf_ifdown(struct net_device *dev, bool unregister);
161 
162 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
163 						  int plen,
164 						  const struct net_device *dev,
165 						  u32 flags, u32 noflags,
166 						  bool no_gw);
167 
168 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
169 static void addrconf_dad_work(struct work_struct *w);
170 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
171 				   bool send_na);
172 static void addrconf_dad_run(struct inet6_dev *idev, bool restart);
173 static void addrconf_rs_timer(struct timer_list *t);
174 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
175 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
176 
177 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
178 				struct prefix_info *pinfo);
179 
180 static struct ipv6_devconf ipv6_devconf __read_mostly = {
181 	.forwarding		= 0,
182 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
183 	.mtu6			= IPV6_MIN_MTU,
184 	.accept_ra		= 1,
185 	.accept_redirects	= 1,
186 	.autoconf		= 1,
187 	.force_mld_version	= 0,
188 	.mldv1_unsolicited_report_interval = 10 * HZ,
189 	.mldv2_unsolicited_report_interval = HZ,
190 	.dad_transmits		= 1,
191 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
192 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
193 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
194 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
195 	.use_tempaddr		= 0,
196 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
197 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
198 	.regen_min_advance	= REGEN_MIN_ADVANCE,
199 	.regen_max_retry	= REGEN_MAX_RETRY,
200 	.max_desync_factor	= MAX_DESYNC_FACTOR,
201 	.max_addresses		= IPV6_MAX_ADDRESSES,
202 	.accept_ra_defrtr	= 1,
203 	.ra_defrtr_metric	= IP6_RT_PRIO_USER,
204 	.accept_ra_from_local	= 0,
205 	.accept_ra_min_hop_limit= 1,
206 	.accept_ra_min_lft	= 0,
207 	.accept_ra_pinfo	= 1,
208 #ifdef CONFIG_IPV6_ROUTER_PREF
209 	.accept_ra_rtr_pref	= 1,
210 	.rtr_probe_interval	= 60 * HZ,
211 #ifdef CONFIG_IPV6_ROUTE_INFO
212 	.accept_ra_rt_info_min_plen = 0,
213 	.accept_ra_rt_info_max_plen = 0,
214 #endif
215 #endif
216 	.proxy_ndp		= 0,
217 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
218 	.disable_ipv6		= 0,
219 	.accept_dad		= 0,
220 	.suppress_frag_ndisc	= 1,
221 	.accept_ra_mtu		= 1,
222 	.stable_secret		= {
223 		.initialized = false,
224 	},
225 	.use_oif_addrs_only	= 0,
226 	.ignore_routes_with_linkdown = 0,
227 	.keep_addr_on_down	= 0,
228 	.seg6_enabled		= 0,
229 #ifdef CONFIG_IPV6_SEG6_HMAC
230 	.seg6_require_hmac	= 0,
231 #endif
232 	.enhanced_dad           = 1,
233 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
234 	.disable_policy		= 0,
235 	.rpl_seg_enabled	= 0,
236 	.ioam6_enabled		= 0,
237 	.ioam6_id               = IOAM6_DEFAULT_IF_ID,
238 	.ioam6_id_wide		= IOAM6_DEFAULT_IF_ID_WIDE,
239 	.ndisc_evict_nocarrier	= 1,
240 	.ra_honor_pio_life	= 0,
241 	.ra_honor_pio_pflag	= 0,
242 };
243 
244 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
245 	.forwarding		= 0,
246 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
247 	.mtu6			= IPV6_MIN_MTU,
248 	.accept_ra		= 1,
249 	.accept_redirects	= 1,
250 	.autoconf		= 1,
251 	.force_mld_version	= 0,
252 	.mldv1_unsolicited_report_interval = 10 * HZ,
253 	.mldv2_unsolicited_report_interval = HZ,
254 	.dad_transmits		= 1,
255 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
256 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
257 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
258 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
259 	.use_tempaddr		= 0,
260 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
261 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
262 	.regen_min_advance	= REGEN_MIN_ADVANCE,
263 	.regen_max_retry	= REGEN_MAX_RETRY,
264 	.max_desync_factor	= MAX_DESYNC_FACTOR,
265 	.max_addresses		= IPV6_MAX_ADDRESSES,
266 	.accept_ra_defrtr	= 1,
267 	.ra_defrtr_metric	= IP6_RT_PRIO_USER,
268 	.accept_ra_from_local	= 0,
269 	.accept_ra_min_hop_limit= 1,
270 	.accept_ra_min_lft	= 0,
271 	.accept_ra_pinfo	= 1,
272 #ifdef CONFIG_IPV6_ROUTER_PREF
273 	.accept_ra_rtr_pref	= 1,
274 	.rtr_probe_interval	= 60 * HZ,
275 #ifdef CONFIG_IPV6_ROUTE_INFO
276 	.accept_ra_rt_info_min_plen = 0,
277 	.accept_ra_rt_info_max_plen = 0,
278 #endif
279 #endif
280 	.proxy_ndp		= 0,
281 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
282 	.disable_ipv6		= 0,
283 	.accept_dad		= 1,
284 	.suppress_frag_ndisc	= 1,
285 	.accept_ra_mtu		= 1,
286 	.stable_secret		= {
287 		.initialized = false,
288 	},
289 	.use_oif_addrs_only	= 0,
290 	.ignore_routes_with_linkdown = 0,
291 	.keep_addr_on_down	= 0,
292 	.seg6_enabled		= 0,
293 #ifdef CONFIG_IPV6_SEG6_HMAC
294 	.seg6_require_hmac	= 0,
295 #endif
296 	.enhanced_dad           = 1,
297 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
298 	.disable_policy		= 0,
299 	.rpl_seg_enabled	= 0,
300 	.ioam6_enabled		= 0,
301 	.ioam6_id               = IOAM6_DEFAULT_IF_ID,
302 	.ioam6_id_wide		= IOAM6_DEFAULT_IF_ID_WIDE,
303 	.ndisc_evict_nocarrier	= 1,
304 	.ra_honor_pio_life	= 0,
305 	.ra_honor_pio_pflag	= 0,
306 };
307 
308 /* Check if link is ready: is it up and is a valid qdisc available */
addrconf_link_ready(const struct net_device * dev)309 static inline bool addrconf_link_ready(const struct net_device *dev)
310 {
311 	return netif_oper_up(dev) && !qdisc_tx_is_noop(dev);
312 }
313 
addrconf_del_rs_timer(struct inet6_dev * idev)314 static void addrconf_del_rs_timer(struct inet6_dev *idev)
315 {
316 	if (timer_delete(&idev->rs_timer))
317 		__in6_dev_put(idev);
318 }
319 
addrconf_del_dad_work(struct inet6_ifaddr * ifp)320 static void addrconf_del_dad_work(struct inet6_ifaddr *ifp)
321 {
322 	if (cancel_delayed_work(&ifp->dad_work))
323 		__in6_ifa_put(ifp);
324 }
325 
addrconf_mod_rs_timer(struct inet6_dev * idev,unsigned long when)326 static void addrconf_mod_rs_timer(struct inet6_dev *idev,
327 				  unsigned long when)
328 {
329 	if (!mod_timer(&idev->rs_timer, jiffies + when))
330 		in6_dev_hold(idev);
331 }
332 
addrconf_mod_dad_work(struct inet6_ifaddr * ifp,unsigned long delay)333 static void addrconf_mod_dad_work(struct inet6_ifaddr *ifp,
334 				   unsigned long delay)
335 {
336 	in6_ifa_hold(ifp);
337 	if (mod_delayed_work(addrconf_wq, &ifp->dad_work, delay))
338 		in6_ifa_put(ifp);
339 }
340 
snmp6_alloc_dev(struct inet6_dev * idev)341 static int snmp6_alloc_dev(struct inet6_dev *idev)
342 {
343 	int i;
344 
345 	idev->stats.ipv6 = alloc_percpu_gfp(struct ipstats_mib, GFP_KERNEL_ACCOUNT);
346 	if (!idev->stats.ipv6)
347 		goto err_ip;
348 
349 	for_each_possible_cpu(i) {
350 		struct ipstats_mib *addrconf_stats;
351 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6, i);
352 		u64_stats_init(&addrconf_stats->syncp);
353 	}
354 
355 
356 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
357 					GFP_KERNEL);
358 	if (!idev->stats.icmpv6dev)
359 		goto err_icmp;
360 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
361 					   GFP_KERNEL_ACCOUNT);
362 	if (!idev->stats.icmpv6msgdev)
363 		goto err_icmpmsg;
364 
365 	return 0;
366 
367 err_icmpmsg:
368 	kfree(idev->stats.icmpv6dev);
369 err_icmp:
370 	free_percpu(idev->stats.ipv6);
371 err_ip:
372 	return -ENOMEM;
373 }
374 
ipv6_add_dev(struct net_device * dev)375 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
376 {
377 	struct inet6_dev *ndev;
378 	int err = -ENOMEM;
379 
380 	ASSERT_RTNL();
381 	netdev_ops_assert_locked(dev);
382 
383 	if (dev->mtu < IPV6_MIN_MTU && dev != blackhole_netdev)
384 		return ERR_PTR(-EINVAL);
385 
386 	ndev = kzalloc(sizeof(*ndev), GFP_KERNEL_ACCOUNT);
387 	if (!ndev)
388 		return ERR_PTR(err);
389 
390 	rwlock_init(&ndev->lock);
391 	ndev->dev = dev;
392 	INIT_LIST_HEAD(&ndev->addr_list);
393 	timer_setup(&ndev->rs_timer, addrconf_rs_timer, 0);
394 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
395 
396 	if (ndev->cnf.stable_secret.initialized)
397 		ndev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
398 
399 	ndev->cnf.mtu6 = dev->mtu;
400 	ndev->ra_mtu = 0;
401 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
402 	if (!ndev->nd_parms) {
403 		kfree(ndev);
404 		return ERR_PTR(err);
405 	}
406 	if (ndev->cnf.forwarding)
407 		netif_disable_lro(dev);
408 	/* We refer to the device */
409 	netdev_hold(dev, &ndev->dev_tracker, GFP_KERNEL);
410 
411 	if (snmp6_alloc_dev(ndev) < 0) {
412 		netdev_dbg(dev, "%s: cannot allocate memory for statistics\n",
413 			   __func__);
414 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
415 		netdev_put(dev, &ndev->dev_tracker);
416 		kfree(ndev);
417 		return ERR_PTR(err);
418 	}
419 
420 	if (dev != blackhole_netdev) {
421 		if (snmp6_register_dev(ndev) < 0) {
422 			netdev_dbg(dev, "%s: cannot create /proc/net/dev_snmp6/%s\n",
423 				   __func__, dev->name);
424 			goto err_release;
425 		}
426 	}
427 	/* One reference from device. */
428 	refcount_set(&ndev->refcnt, 1);
429 
430 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
431 		ndev->cnf.accept_dad = -1;
432 
433 #if IS_ENABLED(CONFIG_IPV6_SIT)
434 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
435 		pr_info("%s: Disabled Multicast RS\n", dev->name);
436 		ndev->cnf.rtr_solicits = 0;
437 	}
438 #endif
439 
440 	INIT_LIST_HEAD(&ndev->tempaddr_list);
441 	ndev->desync_factor = U32_MAX;
442 	if ((dev->flags&IFF_LOOPBACK) ||
443 	    dev->type == ARPHRD_TUNNEL ||
444 	    dev->type == ARPHRD_TUNNEL6 ||
445 	    dev->type == ARPHRD_SIT ||
446 	    dev->type == ARPHRD_NONE) {
447 		ndev->cnf.use_tempaddr = -1;
448 	}
449 
450 	ndev->token = in6addr_any;
451 
452 	if (netif_running(dev) && addrconf_link_ready(dev))
453 		ndev->if_flags |= IF_READY;
454 
455 	ipv6_mc_init_dev(ndev);
456 	ndev->tstamp = jiffies;
457 	if (dev != blackhole_netdev) {
458 		err = addrconf_sysctl_register(ndev);
459 		if (err) {
460 			ipv6_mc_destroy_dev(ndev);
461 			snmp6_unregister_dev(ndev);
462 			goto err_release;
463 		}
464 	}
465 	/* protected by rtnl_lock */
466 	rcu_assign_pointer(dev->ip6_ptr, ndev);
467 
468 	if (dev != blackhole_netdev) {
469 		/* Join interface-local all-node multicast group */
470 		ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
471 
472 		/* Join all-node multicast group */
473 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
474 
475 		/* Join all-router multicast group if forwarding is set */
476 		if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
477 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
478 	}
479 	return ndev;
480 
481 err_release:
482 	neigh_parms_release(&nd_tbl, ndev->nd_parms);
483 	ndev->dead = 1;
484 	in6_dev_finish_destroy(ndev);
485 	return ERR_PTR(err);
486 }
487 
ipv6_find_idev(struct net_device * dev)488 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
489 {
490 	struct inet6_dev *idev;
491 
492 	ASSERT_RTNL();
493 
494 	idev = __in6_dev_get(dev);
495 	if (!idev) {
496 		idev = ipv6_add_dev(dev);
497 		if (IS_ERR(idev))
498 			return idev;
499 	}
500 
501 	if (dev->flags&IFF_UP)
502 		ipv6_mc_up(idev);
503 	return idev;
504 }
505 
inet6_netconf_msgsize_devconf(int type)506 static int inet6_netconf_msgsize_devconf(int type)
507 {
508 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
509 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
510 	bool all = false;
511 
512 	if (type == NETCONFA_ALL)
513 		all = true;
514 
515 	if (all || type == NETCONFA_FORWARDING)
516 		size += nla_total_size(4);
517 #ifdef CONFIG_IPV6_MROUTE
518 	if (all || type == NETCONFA_MC_FORWARDING)
519 		size += nla_total_size(4);
520 #endif
521 	if (all || type == NETCONFA_PROXY_NEIGH)
522 		size += nla_total_size(4);
523 
524 	if (all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN)
525 		size += nla_total_size(4);
526 
527 	return size;
528 }
529 
inet6_netconf_fill_devconf(struct sk_buff * skb,int ifindex,struct ipv6_devconf * devconf,u32 portid,u32 seq,int event,unsigned int flags,int type)530 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
531 				      struct ipv6_devconf *devconf, u32 portid,
532 				      u32 seq, int event, unsigned int flags,
533 				      int type)
534 {
535 	struct nlmsghdr  *nlh;
536 	struct netconfmsg *ncm;
537 	bool all = false;
538 
539 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
540 			flags);
541 	if (!nlh)
542 		return -EMSGSIZE;
543 
544 	if (type == NETCONFA_ALL)
545 		all = true;
546 
547 	ncm = nlmsg_data(nlh);
548 	ncm->ncm_family = AF_INET6;
549 
550 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
551 		goto nla_put_failure;
552 
553 	if (!devconf)
554 		goto out;
555 
556 	if ((all || type == NETCONFA_FORWARDING) &&
557 	    nla_put_s32(skb, NETCONFA_FORWARDING,
558 			READ_ONCE(devconf->forwarding)) < 0)
559 		goto nla_put_failure;
560 #ifdef CONFIG_IPV6_MROUTE
561 	if ((all || type == NETCONFA_MC_FORWARDING) &&
562 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
563 			atomic_read(&devconf->mc_forwarding)) < 0)
564 		goto nla_put_failure;
565 #endif
566 	if ((all || type == NETCONFA_PROXY_NEIGH) &&
567 	    nla_put_s32(skb, NETCONFA_PROXY_NEIGH,
568 			READ_ONCE(devconf->proxy_ndp)) < 0)
569 		goto nla_put_failure;
570 
571 	if ((all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) &&
572 	    nla_put_s32(skb, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
573 			READ_ONCE(devconf->ignore_routes_with_linkdown)) < 0)
574 		goto nla_put_failure;
575 
576 out:
577 	nlmsg_end(skb, nlh);
578 	return 0;
579 
580 nla_put_failure:
581 	nlmsg_cancel(skb, nlh);
582 	return -EMSGSIZE;
583 }
584 
inet6_netconf_notify_devconf(struct net * net,int event,int type,int ifindex,struct ipv6_devconf * devconf)585 void inet6_netconf_notify_devconf(struct net *net, int event, int type,
586 				  int ifindex, struct ipv6_devconf *devconf)
587 {
588 	struct sk_buff *skb;
589 	int err = -ENOBUFS;
590 
591 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_KERNEL);
592 	if (!skb)
593 		goto errout;
594 
595 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
596 					 event, 0, type);
597 	if (err < 0) {
598 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
599 		WARN_ON(err == -EMSGSIZE);
600 		kfree_skb(skb);
601 		goto errout;
602 	}
603 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_KERNEL);
604 	return;
605 errout:
606 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
607 }
608 
609 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
610 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
611 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
612 	[NETCONFA_PROXY_NEIGH]	= { .len = sizeof(int) },
613 	[NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN]	= { .len = sizeof(int) },
614 };
615 
inet6_netconf_valid_get_req(struct sk_buff * skb,const struct nlmsghdr * nlh,struct nlattr ** tb,struct netlink_ext_ack * extack)616 static int inet6_netconf_valid_get_req(struct sk_buff *skb,
617 				       const struct nlmsghdr *nlh,
618 				       struct nlattr **tb,
619 				       struct netlink_ext_ack *extack)
620 {
621 	int i, err;
622 
623 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(struct netconfmsg))) {
624 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf get request");
625 		return -EINVAL;
626 	}
627 
628 	if (!netlink_strict_get_check(skb))
629 		return nlmsg_parse_deprecated(nlh, sizeof(struct netconfmsg),
630 					      tb, NETCONFA_MAX,
631 					      devconf_ipv6_policy, extack);
632 
633 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct netconfmsg),
634 					    tb, NETCONFA_MAX,
635 					    devconf_ipv6_policy, extack);
636 	if (err)
637 		return err;
638 
639 	for (i = 0; i <= NETCONFA_MAX; i++) {
640 		if (!tb[i])
641 			continue;
642 
643 		switch (i) {
644 		case NETCONFA_IFINDEX:
645 			break;
646 		default:
647 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in netconf get request");
648 			return -EINVAL;
649 		}
650 	}
651 
652 	return 0;
653 }
654 
inet6_netconf_get_devconf(struct sk_buff * in_skb,struct nlmsghdr * nlh,struct netlink_ext_ack * extack)655 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
656 				     struct nlmsghdr *nlh,
657 				     struct netlink_ext_ack *extack)
658 {
659 	struct net *net = sock_net(in_skb->sk);
660 	struct nlattr *tb[NETCONFA_MAX+1];
661 	struct inet6_dev *in6_dev = NULL;
662 	struct net_device *dev = NULL;
663 	struct sk_buff *skb;
664 	struct ipv6_devconf *devconf;
665 	int ifindex;
666 	int err;
667 
668 	err = inet6_netconf_valid_get_req(in_skb, nlh, tb, extack);
669 	if (err < 0)
670 		return err;
671 
672 	if (!tb[NETCONFA_IFINDEX])
673 		return -EINVAL;
674 
675 	err = -EINVAL;
676 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
677 	switch (ifindex) {
678 	case NETCONFA_IFINDEX_ALL:
679 		devconf = net->ipv6.devconf_all;
680 		break;
681 	case NETCONFA_IFINDEX_DEFAULT:
682 		devconf = net->ipv6.devconf_dflt;
683 		break;
684 	default:
685 		dev = dev_get_by_index(net, ifindex);
686 		if (!dev)
687 			return -EINVAL;
688 		in6_dev = in6_dev_get(dev);
689 		if (!in6_dev)
690 			goto errout;
691 		devconf = &in6_dev->cnf;
692 		break;
693 	}
694 
695 	err = -ENOBUFS;
696 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL);
697 	if (!skb)
698 		goto errout;
699 
700 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
701 					 NETLINK_CB(in_skb).portid,
702 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
703 					 NETCONFA_ALL);
704 	if (err < 0) {
705 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
706 		WARN_ON(err == -EMSGSIZE);
707 		kfree_skb(skb);
708 		goto errout;
709 	}
710 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
711 errout:
712 	if (in6_dev)
713 		in6_dev_put(in6_dev);
714 	dev_put(dev);
715 	return err;
716 }
717 
718 /* Combine dev_addr_genid and dev_base_seq to detect changes.
719  */
inet6_base_seq(const struct net * net)720 static u32 inet6_base_seq(const struct net *net)
721 {
722 	u32 res = atomic_read(&net->ipv6.dev_addr_genid) +
723 		  READ_ONCE(net->dev_base_seq);
724 
725 	/* Must not return 0 (see nl_dump_check_consistent()).
726 	 * Chose a value far away from 0.
727 	 */
728 	if (!res)
729 		res = 0x80000000;
730 	return res;
731 }
732 
inet6_netconf_dump_devconf(struct sk_buff * skb,struct netlink_callback * cb)733 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
734 				      struct netlink_callback *cb)
735 {
736 	const struct nlmsghdr *nlh = cb->nlh;
737 	struct net *net = sock_net(skb->sk);
738 	struct {
739 		unsigned long ifindex;
740 		unsigned int all_default;
741 	} *ctx = (void *)cb->ctx;
742 	struct net_device *dev;
743 	struct inet6_dev *idev;
744 	int err = 0;
745 
746 	if (cb->strict_check) {
747 		struct netlink_ext_ack *extack = cb->extack;
748 		struct netconfmsg *ncm;
749 
750 		if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ncm))) {
751 			NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf dump request");
752 			return -EINVAL;
753 		}
754 
755 		if (nlmsg_attrlen(nlh, sizeof(*ncm))) {
756 			NL_SET_ERR_MSG_MOD(extack, "Invalid data after header in netconf dump request");
757 			return -EINVAL;
758 		}
759 	}
760 
761 	rcu_read_lock();
762 	for_each_netdev_dump(net, dev, ctx->ifindex) {
763 		idev = __in6_dev_get(dev);
764 		if (!idev)
765 			continue;
766 		err = inet6_netconf_fill_devconf(skb, dev->ifindex,
767 					         &idev->cnf,
768 						 NETLINK_CB(cb->skb).portid,
769 						 nlh->nlmsg_seq,
770 						 RTM_NEWNETCONF,
771 						 NLM_F_MULTI,
772 						 NETCONFA_ALL);
773 		if (err < 0)
774 			goto done;
775 	}
776 	if (ctx->all_default == 0) {
777 		err = inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
778 						 net->ipv6.devconf_all,
779 						 NETLINK_CB(cb->skb).portid,
780 						 nlh->nlmsg_seq,
781 						 RTM_NEWNETCONF, NLM_F_MULTI,
782 						 NETCONFA_ALL);
783 		if (err < 0)
784 			goto done;
785 		ctx->all_default++;
786 	}
787 	if (ctx->all_default == 1) {
788 		err = inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
789 						 net->ipv6.devconf_dflt,
790 						 NETLINK_CB(cb->skb).portid,
791 						 nlh->nlmsg_seq,
792 						 RTM_NEWNETCONF, NLM_F_MULTI,
793 						 NETCONFA_ALL);
794 		if (err < 0)
795 			goto done;
796 		ctx->all_default++;
797 	}
798 done:
799 	rcu_read_unlock();
800 	return err;
801 }
802 
803 #ifdef CONFIG_SYSCTL
dev_forward_change(struct inet6_dev * idev)804 static void dev_forward_change(struct inet6_dev *idev)
805 {
806 	struct net_device *dev;
807 	struct inet6_ifaddr *ifa;
808 	LIST_HEAD(tmp_addr_list);
809 
810 	if (!idev)
811 		return;
812 	dev = idev->dev;
813 	if (idev->cnf.forwarding)
814 		dev_disable_lro(dev);
815 	if (dev->flags & IFF_MULTICAST) {
816 		if (idev->cnf.forwarding) {
817 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
818 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
819 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
820 		} else {
821 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
822 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
823 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
824 		}
825 	}
826 
827 	read_lock_bh(&idev->lock);
828 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
829 		if (ifa->flags&IFA_F_TENTATIVE)
830 			continue;
831 		list_add_tail(&ifa->if_list_aux, &tmp_addr_list);
832 	}
833 	read_unlock_bh(&idev->lock);
834 
835 	while (!list_empty(&tmp_addr_list)) {
836 		ifa = list_first_entry(&tmp_addr_list,
837 				       struct inet6_ifaddr, if_list_aux);
838 		list_del(&ifa->if_list_aux);
839 		if (idev->cnf.forwarding)
840 			addrconf_join_anycast(ifa);
841 		else
842 			addrconf_leave_anycast(ifa);
843 	}
844 
845 	inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
846 				     NETCONFA_FORWARDING,
847 				     dev->ifindex, &idev->cnf);
848 }
849 
850 
addrconf_forward_change(struct net * net,__s32 newf)851 static void addrconf_forward_change(struct net *net, __s32 newf)
852 {
853 	struct net_device *dev;
854 	struct inet6_dev *idev;
855 
856 	for_each_netdev(net, dev) {
857 		idev = __in6_dev_get_rtnl_net(dev);
858 		if (idev) {
859 			int changed = (!idev->cnf.forwarding) ^ (!newf);
860 
861 			WRITE_ONCE(idev->cnf.forwarding, newf);
862 			if (changed)
863 				dev_forward_change(idev);
864 		}
865 	}
866 }
867 
addrconf_fixup_forwarding(const struct ctl_table * table,int * p,int newf)868 static int addrconf_fixup_forwarding(const struct ctl_table *table, int *p, int newf)
869 {
870 	struct net *net = (struct net *)table->extra2;
871 	int old;
872 
873 	if (!rtnl_net_trylock(net))
874 		return restart_syscall();
875 
876 	old = *p;
877 	WRITE_ONCE(*p, newf);
878 
879 	if (p == &net->ipv6.devconf_dflt->forwarding) {
880 		if ((!newf) ^ (!old))
881 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
882 						     NETCONFA_FORWARDING,
883 						     NETCONFA_IFINDEX_DEFAULT,
884 						     net->ipv6.devconf_dflt);
885 		rtnl_net_unlock(net);
886 		return 0;
887 	}
888 
889 	if (p == &net->ipv6.devconf_all->forwarding) {
890 		int old_dflt = net->ipv6.devconf_dflt->forwarding;
891 
892 		WRITE_ONCE(net->ipv6.devconf_dflt->forwarding, newf);
893 		if ((!newf) ^ (!old_dflt))
894 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
895 						     NETCONFA_FORWARDING,
896 						     NETCONFA_IFINDEX_DEFAULT,
897 						     net->ipv6.devconf_dflt);
898 
899 		addrconf_forward_change(net, newf);
900 		if ((!newf) ^ (!old))
901 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
902 						     NETCONFA_FORWARDING,
903 						     NETCONFA_IFINDEX_ALL,
904 						     net->ipv6.devconf_all);
905 	} else if ((!newf) ^ (!old))
906 		dev_forward_change((struct inet6_dev *)table->extra1);
907 	rtnl_net_unlock(net);
908 
909 	if (newf)
910 		rt6_purge_dflt_routers(net);
911 	return 1;
912 }
913 
addrconf_linkdown_change(struct net * net,__s32 newf)914 static void addrconf_linkdown_change(struct net *net, __s32 newf)
915 {
916 	struct net_device *dev;
917 	struct inet6_dev *idev;
918 
919 	for_each_netdev(net, dev) {
920 		idev = __in6_dev_get_rtnl_net(dev);
921 		if (idev) {
922 			int changed = (!idev->cnf.ignore_routes_with_linkdown) ^ (!newf);
923 
924 			WRITE_ONCE(idev->cnf.ignore_routes_with_linkdown, newf);
925 			if (changed)
926 				inet6_netconf_notify_devconf(dev_net(dev),
927 							     RTM_NEWNETCONF,
928 							     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
929 							     dev->ifindex,
930 							     &idev->cnf);
931 		}
932 	}
933 }
934 
addrconf_fixup_linkdown(const struct ctl_table * table,int * p,int newf)935 static int addrconf_fixup_linkdown(const struct ctl_table *table, int *p, int newf)
936 {
937 	struct net *net = (struct net *)table->extra2;
938 	int old;
939 
940 	if (!rtnl_net_trylock(net))
941 		return restart_syscall();
942 
943 	old = *p;
944 	WRITE_ONCE(*p, newf);
945 
946 	if (p == &net->ipv6.devconf_dflt->ignore_routes_with_linkdown) {
947 		if ((!newf) ^ (!old))
948 			inet6_netconf_notify_devconf(net,
949 						     RTM_NEWNETCONF,
950 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
951 						     NETCONFA_IFINDEX_DEFAULT,
952 						     net->ipv6.devconf_dflt);
953 		rtnl_net_unlock(net);
954 		return 0;
955 	}
956 
957 	if (p == &net->ipv6.devconf_all->ignore_routes_with_linkdown) {
958 		WRITE_ONCE(net->ipv6.devconf_dflt->ignore_routes_with_linkdown, newf);
959 		addrconf_linkdown_change(net, newf);
960 		if ((!newf) ^ (!old))
961 			inet6_netconf_notify_devconf(net,
962 						     RTM_NEWNETCONF,
963 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
964 						     NETCONFA_IFINDEX_ALL,
965 						     net->ipv6.devconf_all);
966 	}
967 
968 	rtnl_net_unlock(net);
969 
970 	return 1;
971 }
972 
973 #endif
974 
975 /* Nobody refers to this ifaddr, destroy it */
inet6_ifa_finish_destroy(struct inet6_ifaddr * ifp)976 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
977 {
978 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
979 
980 #ifdef NET_REFCNT_DEBUG
981 	pr_debug("%s\n", __func__);
982 #endif
983 
984 	in6_dev_put(ifp->idev);
985 
986 	if (cancel_delayed_work(&ifp->dad_work))
987 		pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
988 			  ifp);
989 
990 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
991 		pr_warn("Freeing alive inet6 address %p\n", ifp);
992 		return;
993 	}
994 
995 	kfree_rcu(ifp, rcu);
996 }
997 
998 static void
ipv6_link_dev_addr(struct inet6_dev * idev,struct inet6_ifaddr * ifp)999 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
1000 {
1001 	struct list_head *p;
1002 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
1003 
1004 	/*
1005 	 * Each device address list is sorted in order of scope -
1006 	 * global before linklocal.
1007 	 */
1008 	list_for_each(p, &idev->addr_list) {
1009 		struct inet6_ifaddr *ifa
1010 			= list_entry(p, struct inet6_ifaddr, if_list);
1011 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
1012 			break;
1013 	}
1014 
1015 	list_add_tail_rcu(&ifp->if_list, p);
1016 }
1017 
inet6_addr_hash(const struct net * net,const struct in6_addr * addr)1018 static u32 inet6_addr_hash(const struct net *net, const struct in6_addr *addr)
1019 {
1020 	u32 val = __ipv6_addr_jhash(addr, net_hash_mix(net));
1021 
1022 	return hash_32(val, IN6_ADDR_HSIZE_SHIFT);
1023 }
1024 
ipv6_chk_same_addr(struct net * net,const struct in6_addr * addr,struct net_device * dev,unsigned int hash)1025 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
1026 			       struct net_device *dev, unsigned int hash)
1027 {
1028 	struct inet6_ifaddr *ifp;
1029 
1030 	hlist_for_each_entry(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
1031 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1032 			if (!dev || ifp->idev->dev == dev)
1033 				return true;
1034 		}
1035 	}
1036 	return false;
1037 }
1038 
ipv6_add_addr_hash(struct net_device * dev,struct inet6_ifaddr * ifa)1039 static int ipv6_add_addr_hash(struct net_device *dev, struct inet6_ifaddr *ifa)
1040 {
1041 	struct net *net = dev_net(dev);
1042 	unsigned int hash = inet6_addr_hash(net, &ifa->addr);
1043 	int err = 0;
1044 
1045 	spin_lock_bh(&net->ipv6.addrconf_hash_lock);
1046 
1047 	/* Ignore adding duplicate addresses on an interface */
1048 	if (ipv6_chk_same_addr(net, &ifa->addr, dev, hash)) {
1049 		netdev_dbg(dev, "ipv6_add_addr: already assigned\n");
1050 		err = -EEXIST;
1051 	} else {
1052 		hlist_add_head_rcu(&ifa->addr_lst, &net->ipv6.inet6_addr_lst[hash]);
1053 	}
1054 
1055 	spin_unlock_bh(&net->ipv6.addrconf_hash_lock);
1056 
1057 	return err;
1058 }
1059 
1060 /* On success it returns ifp with increased reference count */
1061 
1062 static struct inet6_ifaddr *
ipv6_add_addr(struct inet6_dev * idev,struct ifa6_config * cfg,bool can_block,struct netlink_ext_ack * extack)1063 ipv6_add_addr(struct inet6_dev *idev, struct ifa6_config *cfg,
1064 	      bool can_block, struct netlink_ext_ack *extack)
1065 {
1066 	gfp_t gfp_flags = can_block ? GFP_KERNEL : GFP_ATOMIC;
1067 	int addr_type = ipv6_addr_type(cfg->pfx);
1068 	struct net *net = dev_net(idev->dev);
1069 	struct inet6_ifaddr *ifa = NULL;
1070 	struct fib6_info *f6i = NULL;
1071 	int err = 0;
1072 
1073 	if (addr_type == IPV6_ADDR_ANY) {
1074 		NL_SET_ERR_MSG_MOD(extack, "Invalid address");
1075 		return ERR_PTR(-EADDRNOTAVAIL);
1076 	} else if (addr_type & IPV6_ADDR_MULTICAST &&
1077 		   !(cfg->ifa_flags & IFA_F_MCAUTOJOIN)) {
1078 		NL_SET_ERR_MSG_MOD(extack, "Cannot assign multicast address without \"IFA_F_MCAUTOJOIN\" flag");
1079 		return ERR_PTR(-EADDRNOTAVAIL);
1080 	} else if (!(idev->dev->flags & IFF_LOOPBACK) &&
1081 		   !netif_is_l3_master(idev->dev) &&
1082 		   addr_type & IPV6_ADDR_LOOPBACK) {
1083 		NL_SET_ERR_MSG_MOD(extack, "Cannot assign loopback address on this device");
1084 		return ERR_PTR(-EADDRNOTAVAIL);
1085 	}
1086 
1087 	if (idev->dead) {
1088 		NL_SET_ERR_MSG_MOD(extack, "device is going away");
1089 		err = -ENODEV;
1090 		goto out;
1091 	}
1092 
1093 	if (idev->cnf.disable_ipv6) {
1094 		NL_SET_ERR_MSG_MOD(extack, "IPv6 is disabled on this device");
1095 		err = -EACCES;
1096 		goto out;
1097 	}
1098 
1099 	/* validator notifier needs to be blocking;
1100 	 * do not call in atomic context
1101 	 */
1102 	if (can_block) {
1103 		struct in6_validator_info i6vi = {
1104 			.i6vi_addr = *cfg->pfx,
1105 			.i6vi_dev = idev,
1106 			.extack = extack,
1107 		};
1108 
1109 		err = inet6addr_validator_notifier_call_chain(NETDEV_UP, &i6vi);
1110 		err = notifier_to_errno(err);
1111 		if (err < 0)
1112 			goto out;
1113 	}
1114 
1115 	ifa = kzalloc(sizeof(*ifa), gfp_flags | __GFP_ACCOUNT);
1116 	if (!ifa) {
1117 		err = -ENOBUFS;
1118 		goto out;
1119 	}
1120 
1121 	f6i = addrconf_f6i_alloc(net, idev, cfg->pfx, false, gfp_flags, extack);
1122 	if (IS_ERR(f6i)) {
1123 		err = PTR_ERR(f6i);
1124 		f6i = NULL;
1125 		goto out;
1126 	}
1127 
1128 	neigh_parms_data_state_setall(idev->nd_parms);
1129 
1130 	ifa->addr = *cfg->pfx;
1131 	if (cfg->peer_pfx)
1132 		ifa->peer_addr = *cfg->peer_pfx;
1133 
1134 	spin_lock_init(&ifa->lock);
1135 	INIT_DELAYED_WORK(&ifa->dad_work, addrconf_dad_work);
1136 	INIT_HLIST_NODE(&ifa->addr_lst);
1137 	ifa->scope = cfg->scope;
1138 	ifa->prefix_len = cfg->plen;
1139 	ifa->rt_priority = cfg->rt_priority;
1140 	ifa->flags = cfg->ifa_flags;
1141 	ifa->ifa_proto = cfg->ifa_proto;
1142 	/* No need to add the TENTATIVE flag for addresses with NODAD */
1143 	if (!(cfg->ifa_flags & IFA_F_NODAD))
1144 		ifa->flags |= IFA_F_TENTATIVE;
1145 	ifa->valid_lft = cfg->valid_lft;
1146 	ifa->prefered_lft = cfg->preferred_lft;
1147 	ifa->cstamp = ifa->tstamp = jiffies;
1148 	ifa->tokenized = false;
1149 
1150 	ifa->rt = f6i;
1151 
1152 	ifa->idev = idev;
1153 	in6_dev_hold(idev);
1154 
1155 	/* For caller */
1156 	refcount_set(&ifa->refcnt, 1);
1157 
1158 	rcu_read_lock();
1159 
1160 	err = ipv6_add_addr_hash(idev->dev, ifa);
1161 	if (err < 0) {
1162 		rcu_read_unlock();
1163 		goto out;
1164 	}
1165 
1166 	write_lock_bh(&idev->lock);
1167 
1168 	/* Add to inet6_dev unicast addr list. */
1169 	ipv6_link_dev_addr(idev, ifa);
1170 
1171 	if (ifa->flags&IFA_F_TEMPORARY) {
1172 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
1173 		in6_ifa_hold(ifa);
1174 	}
1175 
1176 	in6_ifa_hold(ifa);
1177 	write_unlock_bh(&idev->lock);
1178 
1179 	rcu_read_unlock();
1180 
1181 	inet6addr_notifier_call_chain(NETDEV_UP, ifa);
1182 out:
1183 	if (unlikely(err < 0)) {
1184 		fib6_info_release(f6i);
1185 
1186 		if (ifa) {
1187 			if (ifa->idev)
1188 				in6_dev_put(ifa->idev);
1189 			kfree(ifa);
1190 		}
1191 		ifa = ERR_PTR(err);
1192 	}
1193 
1194 	return ifa;
1195 }
1196 
1197 enum cleanup_prefix_rt_t {
1198 	CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */
1199 	CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */
1200 	CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */
1201 };
1202 
1203 /*
1204  * Check, whether the prefix for ifp would still need a prefix route
1205  * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*
1206  * constants.
1207  *
1208  * 1) we don't purge prefix if address was not permanent.
1209  *    prefix is managed by its own lifetime.
1210  * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.
1211  * 3) if there are no addresses, delete prefix.
1212  * 4) if there are still other permanent address(es),
1213  *    corresponding prefix is still permanent.
1214  * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,
1215  *    don't purge the prefix, assume user space is managing it.
1216  * 6) otherwise, update prefix lifetime to the
1217  *    longest valid lifetime among the corresponding
1218  *    addresses on the device.
1219  *    Note: subsequent RA will update lifetime.
1220  **/
1221 static enum cleanup_prefix_rt_t
check_cleanup_prefix_route(struct inet6_ifaddr * ifp,unsigned long * expires)1222 check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)
1223 {
1224 	struct inet6_ifaddr *ifa;
1225 	struct inet6_dev *idev = ifp->idev;
1226 	unsigned long lifetime;
1227 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;
1228 
1229 	*expires = jiffies;
1230 
1231 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
1232 		if (ifa == ifp)
1233 			continue;
1234 		if (ifa->prefix_len != ifp->prefix_len ||
1235 		    !ipv6_prefix_equal(&ifa->addr, &ifp->addr,
1236 				       ifp->prefix_len))
1237 			continue;
1238 		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
1239 			return CLEANUP_PREFIX_RT_NOP;
1240 
1241 		action = CLEANUP_PREFIX_RT_EXPIRE;
1242 
1243 		spin_lock(&ifa->lock);
1244 
1245 		lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
1246 		/*
1247 		 * Note: Because this address is
1248 		 * not permanent, lifetime <
1249 		 * LONG_MAX / HZ here.
1250 		 */
1251 		if (time_before(*expires, ifa->tstamp + lifetime * HZ))
1252 			*expires = ifa->tstamp + lifetime * HZ;
1253 		spin_unlock(&ifa->lock);
1254 	}
1255 
1256 	return action;
1257 }
1258 
1259 static void
cleanup_prefix_route(struct inet6_ifaddr * ifp,unsigned long expires,bool del_rt,bool del_peer)1260 cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires,
1261 		     bool del_rt, bool del_peer)
1262 {
1263 	struct fib6_table *table;
1264 	struct fib6_info *f6i;
1265 
1266 	f6i = addrconf_get_prefix_route(del_peer ? &ifp->peer_addr : &ifp->addr,
1267 					ifp->prefix_len,
1268 					ifp->idev->dev, 0, RTF_DEFAULT, true);
1269 	if (f6i) {
1270 		if (del_rt)
1271 			ip6_del_rt(dev_net(ifp->idev->dev), f6i, false);
1272 		else {
1273 			if (!(f6i->fib6_flags & RTF_EXPIRES)) {
1274 				table = f6i->fib6_table;
1275 				spin_lock_bh(&table->tb6_lock);
1276 
1277 				fib6_set_expires(f6i, expires);
1278 				fib6_add_gc_list(f6i);
1279 
1280 				spin_unlock_bh(&table->tb6_lock);
1281 			}
1282 			fib6_info_release(f6i);
1283 		}
1284 	}
1285 }
1286 
1287 
1288 /* This function wants to get referenced ifp and releases it before return */
1289 
ipv6_del_addr(struct inet6_ifaddr * ifp)1290 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
1291 {
1292 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;
1293 	struct net *net = dev_net(ifp->idev->dev);
1294 	unsigned long expires;
1295 	int state;
1296 
1297 	ASSERT_RTNL();
1298 
1299 	spin_lock_bh(&ifp->lock);
1300 	state = ifp->state;
1301 	ifp->state = INET6_IFADDR_STATE_DEAD;
1302 	spin_unlock_bh(&ifp->lock);
1303 
1304 	if (state == INET6_IFADDR_STATE_DEAD)
1305 		goto out;
1306 
1307 	spin_lock_bh(&net->ipv6.addrconf_hash_lock);
1308 	hlist_del_init_rcu(&ifp->addr_lst);
1309 	spin_unlock_bh(&net->ipv6.addrconf_hash_lock);
1310 
1311 	write_lock_bh(&ifp->idev->lock);
1312 
1313 	if (ifp->flags&IFA_F_TEMPORARY) {
1314 		list_del(&ifp->tmp_list);
1315 		if (ifp->ifpub) {
1316 			in6_ifa_put(ifp->ifpub);
1317 			ifp->ifpub = NULL;
1318 		}
1319 		__in6_ifa_put(ifp);
1320 	}
1321 
1322 	if (ifp->flags & IFA_F_PERMANENT && !(ifp->flags & IFA_F_NOPREFIXROUTE))
1323 		action = check_cleanup_prefix_route(ifp, &expires);
1324 
1325 	list_del_rcu(&ifp->if_list);
1326 	__in6_ifa_put(ifp);
1327 
1328 	write_unlock_bh(&ifp->idev->lock);
1329 
1330 	addrconf_del_dad_work(ifp);
1331 
1332 	ipv6_ifa_notify(RTM_DELADDR, ifp);
1333 
1334 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
1335 
1336 	if (action != CLEANUP_PREFIX_RT_NOP) {
1337 		cleanup_prefix_route(ifp, expires,
1338 			action == CLEANUP_PREFIX_RT_DEL, false);
1339 	}
1340 
1341 	/* clean up prefsrc entries */
1342 	rt6_remove_prefsrc(ifp);
1343 out:
1344 	in6_ifa_put(ifp);
1345 }
1346 
ipv6_get_regen_advance(const struct inet6_dev * idev)1347 static unsigned long ipv6_get_regen_advance(const struct inet6_dev *idev)
1348 {
1349 	return READ_ONCE(idev->cnf.regen_min_advance) +
1350 		READ_ONCE(idev->cnf.regen_max_retry) *
1351 		READ_ONCE(idev->cnf.dad_transmits) *
1352 		max(NEIGH_VAR(idev->nd_parms, RETRANS_TIME), HZ/100) / HZ;
1353 }
1354 
ipv6_create_tempaddr(struct inet6_ifaddr * ifp,bool block)1355 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, bool block)
1356 {
1357 	struct inet6_dev *idev = ifp->idev;
1358 	unsigned long tmp_tstamp, age;
1359 	unsigned long regen_advance;
1360 	unsigned long now = jiffies;
1361 	u32 if_public_preferred_lft;
1362 	s32 cnf_temp_preferred_lft;
1363 	struct inet6_ifaddr *ift;
1364 	struct ifa6_config cfg;
1365 	long max_desync_factor;
1366 	struct in6_addr addr;
1367 	int ret = 0;
1368 
1369 	write_lock_bh(&idev->lock);
1370 
1371 retry:
1372 	in6_dev_hold(idev);
1373 	if (READ_ONCE(idev->cnf.use_tempaddr) <= 0) {
1374 		write_unlock_bh(&idev->lock);
1375 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1376 		in6_dev_put(idev);
1377 		ret = -1;
1378 		goto out;
1379 	}
1380 	spin_lock_bh(&ifp->lock);
1381 	if (ifp->regen_count++ >= READ_ONCE(idev->cnf.regen_max_retry)) {
1382 		WRITE_ONCE(idev->cnf.use_tempaddr, -1);	/*XXX*/
1383 		spin_unlock_bh(&ifp->lock);
1384 		write_unlock_bh(&idev->lock);
1385 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1386 			__func__);
1387 		in6_dev_put(idev);
1388 		ret = -1;
1389 		goto out;
1390 	}
1391 	in6_ifa_hold(ifp);
1392 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1393 	ipv6_gen_rnd_iid(&addr);
1394 
1395 	age = (now - ifp->tstamp) / HZ;
1396 
1397 	regen_advance = ipv6_get_regen_advance(idev);
1398 
1399 	/* recalculate max_desync_factor each time and update
1400 	 * idev->desync_factor if it's larger
1401 	 */
1402 	cnf_temp_preferred_lft = READ_ONCE(idev->cnf.temp_prefered_lft);
1403 	max_desync_factor = min_t(long,
1404 				  READ_ONCE(idev->cnf.max_desync_factor),
1405 				  cnf_temp_preferred_lft - regen_advance);
1406 
1407 	if (unlikely(idev->desync_factor > max_desync_factor)) {
1408 		if (max_desync_factor > 0) {
1409 			get_random_bytes(&idev->desync_factor,
1410 					 sizeof(idev->desync_factor));
1411 			idev->desync_factor %= max_desync_factor;
1412 		} else {
1413 			idev->desync_factor = 0;
1414 		}
1415 	}
1416 
1417 	if_public_preferred_lft = ifp->prefered_lft;
1418 
1419 	memset(&cfg, 0, sizeof(cfg));
1420 	cfg.valid_lft = min_t(__u32, ifp->valid_lft,
1421 			      READ_ONCE(idev->cnf.temp_valid_lft) + age);
1422 	cfg.preferred_lft = cnf_temp_preferred_lft + age - idev->desync_factor;
1423 	cfg.preferred_lft = min_t(__u32, if_public_preferred_lft, cfg.preferred_lft);
1424 	cfg.preferred_lft = min_t(__u32, cfg.valid_lft, cfg.preferred_lft);
1425 
1426 	cfg.plen = ifp->prefix_len;
1427 	tmp_tstamp = ifp->tstamp;
1428 	spin_unlock_bh(&ifp->lock);
1429 
1430 	write_unlock_bh(&idev->lock);
1431 
1432 	/* From RFC 4941:
1433 	 *
1434 	 *     A temporary address is created only if this calculated Preferred
1435 	 *     Lifetime is greater than REGEN_ADVANCE time units.  In
1436 	 *     particular, an implementation must not create a temporary address
1437 	 *     with a zero Preferred Lifetime.
1438 	 *
1439 	 *     ...
1440 	 *
1441 	 *     When creating a temporary address, the lifetime values MUST be
1442 	 *     derived from the corresponding prefix as follows:
1443 	 *
1444 	 *     ...
1445 	 *
1446 	 *     *  Its Preferred Lifetime is the lower of the Preferred Lifetime
1447 	 *        of the public address or TEMP_PREFERRED_LIFETIME -
1448 	 *        DESYNC_FACTOR.
1449 	 *
1450 	 * To comply with the RFC's requirements, clamp the preferred lifetime
1451 	 * to a minimum of regen_advance, unless that would exceed valid_lft or
1452 	 * ifp->prefered_lft.
1453 	 *
1454 	 * Use age calculation as in addrconf_verify to avoid unnecessary
1455 	 * temporary addresses being generated.
1456 	 */
1457 	age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1458 	if (cfg.preferred_lft <= regen_advance + age) {
1459 		cfg.preferred_lft = regen_advance + age + 1;
1460 		if (cfg.preferred_lft > cfg.valid_lft ||
1461 		    cfg.preferred_lft > if_public_preferred_lft) {
1462 			in6_ifa_put(ifp);
1463 			in6_dev_put(idev);
1464 			ret = -1;
1465 			goto out;
1466 		}
1467 	}
1468 
1469 	cfg.ifa_flags = IFA_F_TEMPORARY;
1470 	/* set in addrconf_prefix_rcv() */
1471 	if (ifp->flags & IFA_F_OPTIMISTIC)
1472 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
1473 
1474 	cfg.pfx = &addr;
1475 	cfg.scope = ipv6_addr_scope(cfg.pfx);
1476 
1477 	ift = ipv6_add_addr(idev, &cfg, block, NULL);
1478 	if (IS_ERR(ift)) {
1479 		in6_ifa_put(ifp);
1480 		in6_dev_put(idev);
1481 		pr_info("%s: retry temporary address regeneration\n", __func__);
1482 		write_lock_bh(&idev->lock);
1483 		goto retry;
1484 	}
1485 
1486 	spin_lock_bh(&ift->lock);
1487 	ift->ifpub = ifp;
1488 	ift->cstamp = now;
1489 	ift->tstamp = tmp_tstamp;
1490 	spin_unlock_bh(&ift->lock);
1491 
1492 	addrconf_dad_start(ift);
1493 	in6_ifa_put(ift);
1494 	in6_dev_put(idev);
1495 out:
1496 	return ret;
1497 }
1498 
1499 /*
1500  *	Choose an appropriate source address (RFC3484)
1501  */
1502 enum {
1503 	IPV6_SADDR_RULE_INIT = 0,
1504 	IPV6_SADDR_RULE_LOCAL,
1505 	IPV6_SADDR_RULE_SCOPE,
1506 	IPV6_SADDR_RULE_PREFERRED,
1507 #ifdef CONFIG_IPV6_MIP6
1508 	IPV6_SADDR_RULE_HOA,
1509 #endif
1510 	IPV6_SADDR_RULE_OIF,
1511 	IPV6_SADDR_RULE_LABEL,
1512 	IPV6_SADDR_RULE_PRIVACY,
1513 	IPV6_SADDR_RULE_ORCHID,
1514 	IPV6_SADDR_RULE_PREFIX,
1515 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1516 	IPV6_SADDR_RULE_NOT_OPTIMISTIC,
1517 #endif
1518 	IPV6_SADDR_RULE_MAX
1519 };
1520 
1521 struct ipv6_saddr_score {
1522 	int			rule;
1523 	int			addr_type;
1524 	struct inet6_ifaddr	*ifa;
1525 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1526 	int			scopedist;
1527 	int			matchlen;
1528 };
1529 
1530 struct ipv6_saddr_dst {
1531 	const struct in6_addr *addr;
1532 	int ifindex;
1533 	int scope;
1534 	int label;
1535 	unsigned int prefs;
1536 };
1537 
ipv6_saddr_preferred(int type)1538 static inline int ipv6_saddr_preferred(int type)
1539 {
1540 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1541 		return 1;
1542 	return 0;
1543 }
1544 
ipv6_use_optimistic_addr(const struct net * net,const struct inet6_dev * idev)1545 static bool ipv6_use_optimistic_addr(const struct net *net,
1546 				     const struct inet6_dev *idev)
1547 {
1548 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1549 	if (!idev)
1550 		return false;
1551 	if (!READ_ONCE(net->ipv6.devconf_all->optimistic_dad) &&
1552 	    !READ_ONCE(idev->cnf.optimistic_dad))
1553 		return false;
1554 	if (!READ_ONCE(net->ipv6.devconf_all->use_optimistic) &&
1555 	    !READ_ONCE(idev->cnf.use_optimistic))
1556 		return false;
1557 
1558 	return true;
1559 #else
1560 	return false;
1561 #endif
1562 }
1563 
ipv6_allow_optimistic_dad(const struct net * net,const struct inet6_dev * idev)1564 static bool ipv6_allow_optimistic_dad(const struct net *net,
1565 				      const struct inet6_dev *idev)
1566 {
1567 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1568 	if (!idev)
1569 		return false;
1570 	if (!READ_ONCE(net->ipv6.devconf_all->optimistic_dad) &&
1571 	    !READ_ONCE(idev->cnf.optimistic_dad))
1572 		return false;
1573 
1574 	return true;
1575 #else
1576 	return false;
1577 #endif
1578 }
1579 
ipv6_get_saddr_eval(struct net * net,struct ipv6_saddr_score * score,struct ipv6_saddr_dst * dst,int i)1580 static int ipv6_get_saddr_eval(struct net *net,
1581 			       struct ipv6_saddr_score *score,
1582 			       struct ipv6_saddr_dst *dst,
1583 			       int i)
1584 {
1585 	int ret;
1586 
1587 	if (i <= score->rule) {
1588 		switch (i) {
1589 		case IPV6_SADDR_RULE_SCOPE:
1590 			ret = score->scopedist;
1591 			break;
1592 		case IPV6_SADDR_RULE_PREFIX:
1593 			ret = score->matchlen;
1594 			break;
1595 		default:
1596 			ret = !!test_bit(i, score->scorebits);
1597 		}
1598 		goto out;
1599 	}
1600 
1601 	switch (i) {
1602 	case IPV6_SADDR_RULE_INIT:
1603 		/* Rule 0: remember if hiscore is not ready yet */
1604 		ret = !!score->ifa;
1605 		break;
1606 	case IPV6_SADDR_RULE_LOCAL:
1607 		/* Rule 1: Prefer same address */
1608 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1609 		break;
1610 	case IPV6_SADDR_RULE_SCOPE:
1611 		/* Rule 2: Prefer appropriate scope
1612 		 *
1613 		 *      ret
1614 		 *       ^
1615 		 *    -1 |  d 15
1616 		 *    ---+--+-+---> scope
1617 		 *       |
1618 		 *       |             d is scope of the destination.
1619 		 *  B-d  |  \
1620 		 *       |   \      <- smaller scope is better if
1621 		 *  B-15 |    \        if scope is enough for destination.
1622 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1623 		 * d-C-1 | /
1624 		 *       |/         <- greater is better
1625 		 *   -C  /             if scope is not enough for destination.
1626 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1627 		 *
1628 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1629 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1630 		 * Assume B = 0 and we get C > 29.
1631 		 */
1632 		ret = __ipv6_addr_src_scope(score->addr_type);
1633 		if (ret >= dst->scope)
1634 			ret = -ret;
1635 		else
1636 			ret -= 128;	/* 30 is enough */
1637 		score->scopedist = ret;
1638 		break;
1639 	case IPV6_SADDR_RULE_PREFERRED:
1640 	    {
1641 		/* Rule 3: Avoid deprecated and optimistic addresses */
1642 		u8 avoid = IFA_F_DEPRECATED;
1643 
1644 		if (!ipv6_use_optimistic_addr(net, score->ifa->idev))
1645 			avoid |= IFA_F_OPTIMISTIC;
1646 		ret = ipv6_saddr_preferred(score->addr_type) ||
1647 		      !(score->ifa->flags & avoid);
1648 		break;
1649 	    }
1650 #ifdef CONFIG_IPV6_MIP6
1651 	case IPV6_SADDR_RULE_HOA:
1652 	    {
1653 		/* Rule 4: Prefer home address */
1654 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1655 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1656 		break;
1657 	    }
1658 #endif
1659 	case IPV6_SADDR_RULE_OIF:
1660 		/* Rule 5: Prefer outgoing interface */
1661 		ret = (!dst->ifindex ||
1662 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1663 		break;
1664 	case IPV6_SADDR_RULE_LABEL:
1665 		/* Rule 6: Prefer matching label */
1666 		ret = ipv6_addr_label(net,
1667 				      &score->ifa->addr, score->addr_type,
1668 				      score->ifa->idev->dev->ifindex) == dst->label;
1669 		break;
1670 	case IPV6_SADDR_RULE_PRIVACY:
1671 	    {
1672 		/* Rule 7: Prefer public address
1673 		 * Note: prefer temporary address if use_tempaddr >= 2
1674 		 */
1675 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1676 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1677 				READ_ONCE(score->ifa->idev->cnf.use_tempaddr) >= 2;
1678 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1679 		break;
1680 	    }
1681 	case IPV6_SADDR_RULE_ORCHID:
1682 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1683 		 *	    non-ORCHID vs non-ORCHID
1684 		 */
1685 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1686 			ipv6_addr_orchid(dst->addr));
1687 		break;
1688 	case IPV6_SADDR_RULE_PREFIX:
1689 		/* Rule 8: Use longest matching prefix */
1690 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1691 		if (ret > score->ifa->prefix_len)
1692 			ret = score->ifa->prefix_len;
1693 		score->matchlen = ret;
1694 		break;
1695 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1696 	case IPV6_SADDR_RULE_NOT_OPTIMISTIC:
1697 		/* Optimistic addresses still have lower precedence than other
1698 		 * preferred addresses.
1699 		 */
1700 		ret = !(score->ifa->flags & IFA_F_OPTIMISTIC);
1701 		break;
1702 #endif
1703 	default:
1704 		ret = 0;
1705 	}
1706 
1707 	if (ret)
1708 		__set_bit(i, score->scorebits);
1709 	score->rule = i;
1710 out:
1711 	return ret;
1712 }
1713 
__ipv6_dev_get_saddr(struct net * net,struct ipv6_saddr_dst * dst,struct inet6_dev * idev,struct ipv6_saddr_score * scores,int hiscore_idx)1714 static int __ipv6_dev_get_saddr(struct net *net,
1715 				struct ipv6_saddr_dst *dst,
1716 				struct inet6_dev *idev,
1717 				struct ipv6_saddr_score *scores,
1718 				int hiscore_idx)
1719 {
1720 	struct ipv6_saddr_score *score = &scores[1 - hiscore_idx], *hiscore = &scores[hiscore_idx];
1721 
1722 	list_for_each_entry_rcu(score->ifa, &idev->addr_list, if_list) {
1723 		int i;
1724 
1725 		/*
1726 		 * - Tentative Address (RFC2462 section 5.4)
1727 		 *  - A tentative address is not considered
1728 		 *    "assigned to an interface" in the traditional
1729 		 *    sense, unless it is also flagged as optimistic.
1730 		 * - Candidate Source Address (section 4)
1731 		 *  - In any case, anycast addresses, multicast
1732 		 *    addresses, and the unspecified address MUST
1733 		 *    NOT be included in a candidate set.
1734 		 */
1735 		if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1736 		    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1737 			continue;
1738 
1739 		score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1740 
1741 		if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1742 			     score->addr_type & IPV6_ADDR_MULTICAST)) {
1743 			net_dbg_ratelimited("ADDRCONF: unspecified / multicast address assigned as unicast address on %s",
1744 					    idev->dev->name);
1745 			continue;
1746 		}
1747 
1748 		score->rule = -1;
1749 		bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1750 
1751 		for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1752 			int minihiscore, miniscore;
1753 
1754 			minihiscore = ipv6_get_saddr_eval(net, hiscore, dst, i);
1755 			miniscore = ipv6_get_saddr_eval(net, score, dst, i);
1756 
1757 			if (minihiscore > miniscore) {
1758 				if (i == IPV6_SADDR_RULE_SCOPE &&
1759 				    score->scopedist > 0) {
1760 					/*
1761 					 * special case:
1762 					 * each remaining entry
1763 					 * has too small (not enough)
1764 					 * scope, because ifa entries
1765 					 * are sorted by their scope
1766 					 * values.
1767 					 */
1768 					goto out;
1769 				}
1770 				break;
1771 			} else if (minihiscore < miniscore) {
1772 				swap(hiscore, score);
1773 				hiscore_idx = 1 - hiscore_idx;
1774 
1775 				/* restore our iterator */
1776 				score->ifa = hiscore->ifa;
1777 
1778 				break;
1779 			}
1780 		}
1781 	}
1782 out:
1783 	return hiscore_idx;
1784 }
1785 
ipv6_get_saddr_master(struct net * net,const struct net_device * dst_dev,const struct net_device * master,struct ipv6_saddr_dst * dst,struct ipv6_saddr_score * scores,int hiscore_idx)1786 static int ipv6_get_saddr_master(struct net *net,
1787 				 const struct net_device *dst_dev,
1788 				 const struct net_device *master,
1789 				 struct ipv6_saddr_dst *dst,
1790 				 struct ipv6_saddr_score *scores,
1791 				 int hiscore_idx)
1792 {
1793 	struct inet6_dev *idev;
1794 
1795 	idev = __in6_dev_get(dst_dev);
1796 	if (idev)
1797 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1798 						   scores, hiscore_idx);
1799 
1800 	idev = __in6_dev_get(master);
1801 	if (idev)
1802 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1803 						   scores, hiscore_idx);
1804 
1805 	return hiscore_idx;
1806 }
1807 
ipv6_dev_get_saddr(struct net * net,const struct net_device * dst_dev,const struct in6_addr * daddr,unsigned int prefs,struct in6_addr * saddr)1808 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1809 		       const struct in6_addr *daddr, unsigned int prefs,
1810 		       struct in6_addr *saddr)
1811 {
1812 	struct ipv6_saddr_score scores[2], *hiscore;
1813 	struct ipv6_saddr_dst dst;
1814 	struct inet6_dev *idev;
1815 	struct net_device *dev;
1816 	int dst_type;
1817 	bool use_oif_addr = false;
1818 	int hiscore_idx = 0;
1819 	int ret = 0;
1820 
1821 	dst_type = __ipv6_addr_type(daddr);
1822 	dst.addr = daddr;
1823 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1824 	dst.scope = __ipv6_addr_src_scope(dst_type);
1825 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1826 	dst.prefs = prefs;
1827 
1828 	scores[hiscore_idx].rule = -1;
1829 	scores[hiscore_idx].ifa = NULL;
1830 
1831 	rcu_read_lock();
1832 
1833 	/* Candidate Source Address (section 4)
1834 	 *  - multicast and link-local destination address,
1835 	 *    the set of candidate source address MUST only
1836 	 *    include addresses assigned to interfaces
1837 	 *    belonging to the same link as the outgoing
1838 	 *    interface.
1839 	 * (- For site-local destination addresses, the
1840 	 *    set of candidate source addresses MUST only
1841 	 *    include addresses assigned to interfaces
1842 	 *    belonging to the same site as the outgoing
1843 	 *    interface.)
1844 	 *  - "It is RECOMMENDED that the candidate source addresses
1845 	 *    be the set of unicast addresses assigned to the
1846 	 *    interface that will be used to send to the destination
1847 	 *    (the 'outgoing' interface)." (RFC 6724)
1848 	 */
1849 	if (dst_dev) {
1850 		idev = __in6_dev_get(dst_dev);
1851 		if ((dst_type & IPV6_ADDR_MULTICAST) ||
1852 		    dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL ||
1853 		    (idev && READ_ONCE(idev->cnf.use_oif_addrs_only))) {
1854 			use_oif_addr = true;
1855 		}
1856 	}
1857 
1858 	if (use_oif_addr) {
1859 		if (idev)
1860 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1861 	} else {
1862 		const struct net_device *master;
1863 		int master_idx = 0;
1864 
1865 		/* if dst_dev exists and is enslaved to an L3 device, then
1866 		 * prefer addresses from dst_dev and then the master over
1867 		 * any other enslaved devices in the L3 domain.
1868 		 */
1869 		master = l3mdev_master_dev_rcu(dst_dev);
1870 		if (master) {
1871 			master_idx = master->ifindex;
1872 
1873 			hiscore_idx = ipv6_get_saddr_master(net, dst_dev,
1874 							    master, &dst,
1875 							    scores, hiscore_idx);
1876 
1877 			if (scores[hiscore_idx].ifa &&
1878 			    scores[hiscore_idx].scopedist >= 0)
1879 				goto out;
1880 		}
1881 
1882 		for_each_netdev_rcu(net, dev) {
1883 			/* only consider addresses on devices in the
1884 			 * same L3 domain
1885 			 */
1886 			if (l3mdev_master_ifindex_rcu(dev) != master_idx)
1887 				continue;
1888 			idev = __in6_dev_get(dev);
1889 			if (!idev)
1890 				continue;
1891 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1892 		}
1893 	}
1894 
1895 out:
1896 	hiscore = &scores[hiscore_idx];
1897 	if (!hiscore->ifa)
1898 		ret = -EADDRNOTAVAIL;
1899 	else
1900 		*saddr = hiscore->ifa->addr;
1901 
1902 	rcu_read_unlock();
1903 	return ret;
1904 }
1905 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1906 
__ipv6_get_lladdr(struct inet6_dev * idev,struct in6_addr * addr,u32 banned_flags)1907 static int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1908 			      u32 banned_flags)
1909 {
1910 	struct inet6_ifaddr *ifp;
1911 	int err = -EADDRNOTAVAIL;
1912 
1913 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1914 		if (ifp->scope > IFA_LINK)
1915 			break;
1916 		if (ifp->scope == IFA_LINK &&
1917 		    !(ifp->flags & banned_flags)) {
1918 			*addr = ifp->addr;
1919 			err = 0;
1920 			break;
1921 		}
1922 	}
1923 	return err;
1924 }
1925 
ipv6_get_lladdr(struct net_device * dev,struct in6_addr * addr,u32 banned_flags)1926 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1927 		    u32 banned_flags)
1928 {
1929 	struct inet6_dev *idev;
1930 	int err = -EADDRNOTAVAIL;
1931 
1932 	rcu_read_lock();
1933 	idev = __in6_dev_get(dev);
1934 	if (idev) {
1935 		read_lock_bh(&idev->lock);
1936 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1937 		read_unlock_bh(&idev->lock);
1938 	}
1939 	rcu_read_unlock();
1940 	return err;
1941 }
1942 
ipv6_count_addresses(const struct inet6_dev * idev)1943 static int ipv6_count_addresses(const struct inet6_dev *idev)
1944 {
1945 	const struct inet6_ifaddr *ifp;
1946 	int cnt = 0;
1947 
1948 	rcu_read_lock();
1949 	list_for_each_entry_rcu(ifp, &idev->addr_list, if_list)
1950 		cnt++;
1951 	rcu_read_unlock();
1952 	return cnt;
1953 }
1954 
ipv6_chk_addr(struct net * net,const struct in6_addr * addr,const struct net_device * dev,int strict)1955 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1956 		  const struct net_device *dev, int strict)
1957 {
1958 	return ipv6_chk_addr_and_flags(net, addr, dev, !dev,
1959 				       strict, IFA_F_TENTATIVE);
1960 }
1961 EXPORT_SYMBOL(ipv6_chk_addr);
1962 
1963 /* device argument is used to find the L3 domain of interest. If
1964  * skip_dev_check is set, then the ifp device is not checked against
1965  * the passed in dev argument. So the 2 cases for addresses checks are:
1966  *   1. does the address exist in the L3 domain that dev is part of
1967  *      (skip_dev_check = true), or
1968  *
1969  *   2. does the address exist on the specific device
1970  *      (skip_dev_check = false)
1971  */
1972 static struct net_device *
__ipv6_chk_addr_and_flags(struct net * net,const struct in6_addr * addr,const struct net_device * dev,bool skip_dev_check,int strict,u32 banned_flags)1973 __ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1974 			  const struct net_device *dev, bool skip_dev_check,
1975 			  int strict, u32 banned_flags)
1976 {
1977 	unsigned int hash = inet6_addr_hash(net, addr);
1978 	struct net_device *l3mdev, *ndev;
1979 	struct inet6_ifaddr *ifp;
1980 	u32 ifp_flags;
1981 
1982 	rcu_read_lock();
1983 
1984 	l3mdev = l3mdev_master_dev_rcu(dev);
1985 	if (skip_dev_check)
1986 		dev = NULL;
1987 
1988 	hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
1989 		ndev = ifp->idev->dev;
1990 
1991 		if (l3mdev_master_dev_rcu(ndev) != l3mdev)
1992 			continue;
1993 
1994 		/* Decouple optimistic from tentative for evaluation here.
1995 		 * Ban optimistic addresses explicitly, when required.
1996 		 */
1997 		ifp_flags = (ifp->flags&IFA_F_OPTIMISTIC)
1998 			    ? (ifp->flags&~IFA_F_TENTATIVE)
1999 			    : ifp->flags;
2000 		if (ipv6_addr_equal(&ifp->addr, addr) &&
2001 		    !(ifp_flags&banned_flags) &&
2002 		    (!dev || ndev == dev ||
2003 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
2004 			rcu_read_unlock();
2005 			return ndev;
2006 		}
2007 	}
2008 
2009 	rcu_read_unlock();
2010 	return NULL;
2011 }
2012 
ipv6_chk_addr_and_flags(struct net * net,const struct in6_addr * addr,const struct net_device * dev,bool skip_dev_check,int strict,u32 banned_flags)2013 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
2014 			    const struct net_device *dev, bool skip_dev_check,
2015 			    int strict, u32 banned_flags)
2016 {
2017 	return __ipv6_chk_addr_and_flags(net, addr, dev, skip_dev_check,
2018 					 strict, banned_flags) ? 1 : 0;
2019 }
2020 EXPORT_SYMBOL(ipv6_chk_addr_and_flags);
2021 
2022 
2023 /* Compares an address/prefix_len with addresses on device @dev.
2024  * If one is found it returns true.
2025  */
ipv6_chk_custom_prefix(const struct in6_addr * addr,const unsigned int prefix_len,struct net_device * dev)2026 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
2027 	const unsigned int prefix_len, struct net_device *dev)
2028 {
2029 	const struct inet6_ifaddr *ifa;
2030 	const struct inet6_dev *idev;
2031 	bool ret = false;
2032 
2033 	rcu_read_lock();
2034 	idev = __in6_dev_get(dev);
2035 	if (idev) {
2036 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
2037 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
2038 			if (ret)
2039 				break;
2040 		}
2041 	}
2042 	rcu_read_unlock();
2043 
2044 	return ret;
2045 }
2046 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
2047 
ipv6_chk_prefix(const struct in6_addr * addr,struct net_device * dev)2048 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
2049 {
2050 	const struct inet6_ifaddr *ifa;
2051 	const struct inet6_dev *idev;
2052 	int	onlink;
2053 
2054 	onlink = 0;
2055 	rcu_read_lock();
2056 	idev = __in6_dev_get(dev);
2057 	if (idev) {
2058 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
2059 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
2060 						   ifa->prefix_len);
2061 			if (onlink)
2062 				break;
2063 		}
2064 	}
2065 	rcu_read_unlock();
2066 	return onlink;
2067 }
2068 EXPORT_SYMBOL(ipv6_chk_prefix);
2069 
2070 /**
2071  * ipv6_dev_find - find the first device with a given source address.
2072  * @net: the net namespace
2073  * @addr: the source address
2074  * @dev: used to find the L3 domain of interest
2075  *
2076  * The caller should be protected by RCU, or RTNL.
2077  */
ipv6_dev_find(struct net * net,const struct in6_addr * addr,struct net_device * dev)2078 struct net_device *ipv6_dev_find(struct net *net, const struct in6_addr *addr,
2079 				 struct net_device *dev)
2080 {
2081 	return __ipv6_chk_addr_and_flags(net, addr, dev, !dev, 1,
2082 					 IFA_F_TENTATIVE);
2083 }
2084 EXPORT_SYMBOL(ipv6_dev_find);
2085 
ipv6_get_ifaddr(struct net * net,const struct in6_addr * addr,struct net_device * dev,int strict)2086 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
2087 				     struct net_device *dev, int strict)
2088 {
2089 	unsigned int hash = inet6_addr_hash(net, addr);
2090 	struct inet6_ifaddr *ifp, *result = NULL;
2091 
2092 	rcu_read_lock();
2093 	hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
2094 		if (ipv6_addr_equal(&ifp->addr, addr)) {
2095 			if (!dev || ifp->idev->dev == dev ||
2096 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
2097 				if (in6_ifa_hold_safe(ifp)) {
2098 					result = ifp;
2099 					break;
2100 				}
2101 			}
2102 		}
2103 	}
2104 	rcu_read_unlock();
2105 
2106 	return result;
2107 }
2108 
2109 /* Gets referenced address, destroys ifaddr */
2110 
addrconf_dad_stop(struct inet6_ifaddr * ifp,int dad_failed)2111 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
2112 {
2113 	if (dad_failed)
2114 		ifp->flags |= IFA_F_DADFAILED;
2115 
2116 	if (ifp->flags&IFA_F_TEMPORARY) {
2117 		struct inet6_ifaddr *ifpub;
2118 		spin_lock_bh(&ifp->lock);
2119 		ifpub = ifp->ifpub;
2120 		if (ifpub) {
2121 			in6_ifa_hold(ifpub);
2122 			spin_unlock_bh(&ifp->lock);
2123 			ipv6_create_tempaddr(ifpub, true);
2124 			in6_ifa_put(ifpub);
2125 		} else {
2126 			spin_unlock_bh(&ifp->lock);
2127 		}
2128 		ipv6_del_addr(ifp);
2129 	} else if (ifp->flags&IFA_F_PERMANENT || !dad_failed) {
2130 		spin_lock_bh(&ifp->lock);
2131 		addrconf_del_dad_work(ifp);
2132 		ifp->flags |= IFA_F_TENTATIVE;
2133 		if (dad_failed)
2134 			ifp->flags &= ~IFA_F_OPTIMISTIC;
2135 		spin_unlock_bh(&ifp->lock);
2136 		if (dad_failed)
2137 			ipv6_ifa_notify(0, ifp);
2138 		in6_ifa_put(ifp);
2139 	} else {
2140 		ipv6_del_addr(ifp);
2141 	}
2142 }
2143 
addrconf_dad_end(struct inet6_ifaddr * ifp)2144 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
2145 {
2146 	int err = -ENOENT;
2147 
2148 	spin_lock_bh(&ifp->lock);
2149 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
2150 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
2151 		err = 0;
2152 	}
2153 	spin_unlock_bh(&ifp->lock);
2154 
2155 	return err;
2156 }
2157 
addrconf_dad_failure(struct sk_buff * skb,struct inet6_ifaddr * ifp)2158 void addrconf_dad_failure(struct sk_buff *skb, struct inet6_ifaddr *ifp)
2159 {
2160 	struct inet6_dev *idev = ifp->idev;
2161 	struct net *net = dev_net(idev->dev);
2162 	int max_addresses;
2163 
2164 	if (addrconf_dad_end(ifp)) {
2165 		in6_ifa_put(ifp);
2166 		return;
2167 	}
2168 
2169 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c used by %pM detected!\n",
2170 			     ifp->idev->dev->name, &ifp->addr, eth_hdr(skb)->h_source);
2171 
2172 	spin_lock_bh(&ifp->lock);
2173 
2174 	if (ifp->flags & IFA_F_STABLE_PRIVACY) {
2175 		struct in6_addr new_addr;
2176 		struct inet6_ifaddr *ifp2;
2177 		int retries = ifp->stable_privacy_retry + 1;
2178 		struct ifa6_config cfg = {
2179 			.pfx = &new_addr,
2180 			.plen = ifp->prefix_len,
2181 			.ifa_flags = ifp->flags,
2182 			.valid_lft = ifp->valid_lft,
2183 			.preferred_lft = ifp->prefered_lft,
2184 			.scope = ifp->scope,
2185 		};
2186 
2187 		if (retries > net->ipv6.sysctl.idgen_retries) {
2188 			net_info_ratelimited("%s: privacy stable address generation failed because of DAD conflicts!\n",
2189 					     ifp->idev->dev->name);
2190 			goto errdad;
2191 		}
2192 
2193 		new_addr = ifp->addr;
2194 		if (ipv6_generate_stable_address(&new_addr, retries,
2195 						 idev))
2196 			goto errdad;
2197 
2198 		spin_unlock_bh(&ifp->lock);
2199 
2200 		max_addresses = READ_ONCE(idev->cnf.max_addresses);
2201 		if (max_addresses &&
2202 		    ipv6_count_addresses(idev) >= max_addresses)
2203 			goto lock_errdad;
2204 
2205 		net_info_ratelimited("%s: generating new stable privacy address because of DAD conflict\n",
2206 				     ifp->idev->dev->name);
2207 
2208 		ifp2 = ipv6_add_addr(idev, &cfg, false, NULL);
2209 		if (IS_ERR(ifp2))
2210 			goto lock_errdad;
2211 
2212 		spin_lock_bh(&ifp2->lock);
2213 		ifp2->stable_privacy_retry = retries;
2214 		ifp2->state = INET6_IFADDR_STATE_PREDAD;
2215 		spin_unlock_bh(&ifp2->lock);
2216 
2217 		addrconf_mod_dad_work(ifp2, net->ipv6.sysctl.idgen_delay);
2218 		in6_ifa_put(ifp2);
2219 lock_errdad:
2220 		spin_lock_bh(&ifp->lock);
2221 	}
2222 
2223 errdad:
2224 	/* transition from _POSTDAD to _ERRDAD */
2225 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
2226 	spin_unlock_bh(&ifp->lock);
2227 
2228 	addrconf_mod_dad_work(ifp, 0);
2229 	in6_ifa_put(ifp);
2230 }
2231 
2232 /* Join to solicited addr multicast group.
2233  * caller must hold RTNL */
addrconf_join_solict(struct net_device * dev,const struct in6_addr * addr)2234 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
2235 {
2236 	struct in6_addr maddr;
2237 
2238 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2239 		return;
2240 
2241 	addrconf_addr_solict_mult(addr, &maddr);
2242 	ipv6_dev_mc_inc(dev, &maddr);
2243 }
2244 
2245 /* caller must hold RTNL */
addrconf_leave_solict(struct inet6_dev * idev,const struct in6_addr * addr)2246 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
2247 {
2248 	struct in6_addr maddr;
2249 
2250 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2251 		return;
2252 
2253 	addrconf_addr_solict_mult(addr, &maddr);
2254 	__ipv6_dev_mc_dec(idev, &maddr);
2255 }
2256 
2257 /* caller must hold RTNL */
addrconf_join_anycast(struct inet6_ifaddr * ifp)2258 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
2259 {
2260 	struct in6_addr addr;
2261 
2262 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2263 		return;
2264 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2265 	if (ipv6_addr_any(&addr))
2266 		return;
2267 	__ipv6_dev_ac_inc(ifp->idev, &addr);
2268 }
2269 
2270 /* caller must hold RTNL */
addrconf_leave_anycast(struct inet6_ifaddr * ifp)2271 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
2272 {
2273 	struct in6_addr addr;
2274 
2275 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2276 		return;
2277 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2278 	if (ipv6_addr_any(&addr))
2279 		return;
2280 	__ipv6_dev_ac_dec(ifp->idev, &addr);
2281 }
2282 
addrconf_ifid_6lowpan(u8 * eui,struct net_device * dev)2283 static int addrconf_ifid_6lowpan(u8 *eui, struct net_device *dev)
2284 {
2285 	switch (dev->addr_len) {
2286 	case ETH_ALEN:
2287 		memcpy(eui, dev->dev_addr, 3);
2288 		eui[3] = 0xFF;
2289 		eui[4] = 0xFE;
2290 		memcpy(eui + 5, dev->dev_addr + 3, 3);
2291 		break;
2292 	case EUI64_ADDR_LEN:
2293 		memcpy(eui, dev->dev_addr, EUI64_ADDR_LEN);
2294 		eui[0] ^= 2;
2295 		break;
2296 	default:
2297 		return -1;
2298 	}
2299 
2300 	return 0;
2301 }
2302 
addrconf_ifid_ieee1394(u8 * eui,struct net_device * dev)2303 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
2304 {
2305 	const union fwnet_hwaddr *ha;
2306 
2307 	if (dev->addr_len != FWNET_ALEN)
2308 		return -1;
2309 
2310 	ha = (const union fwnet_hwaddr *)dev->dev_addr;
2311 
2312 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
2313 	eui[0] ^= 2;
2314 	return 0;
2315 }
2316 
addrconf_ifid_arcnet(u8 * eui,struct net_device * dev)2317 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
2318 {
2319 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
2320 	if (dev->addr_len != ARCNET_ALEN)
2321 		return -1;
2322 	memset(eui, 0, 7);
2323 	eui[7] = *(u8 *)dev->dev_addr;
2324 	return 0;
2325 }
2326 
addrconf_ifid_infiniband(u8 * eui,struct net_device * dev)2327 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
2328 {
2329 	if (dev->addr_len != INFINIBAND_ALEN)
2330 		return -1;
2331 	memcpy(eui, dev->dev_addr + 12, 8);
2332 	eui[0] |= 2;
2333 	return 0;
2334 }
2335 
__ipv6_isatap_ifid(u8 * eui,__be32 addr)2336 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
2337 {
2338 	if (addr == 0)
2339 		return -1;
2340 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
2341 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
2342 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
2343 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
2344 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
2345 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
2346 	eui[1] = 0;
2347 	eui[2] = 0x5E;
2348 	eui[3] = 0xFE;
2349 	memcpy(eui + 4, &addr, 4);
2350 	return 0;
2351 }
2352 
addrconf_ifid_sit(u8 * eui,struct net_device * dev)2353 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
2354 {
2355 	if (dev->priv_flags & IFF_ISATAP)
2356 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2357 	return -1;
2358 }
2359 
addrconf_ifid_gre(u8 * eui,struct net_device * dev)2360 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
2361 {
2362 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2363 }
2364 
addrconf_ifid_ip6tnl(u8 * eui,struct net_device * dev)2365 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
2366 {
2367 	memcpy(eui, dev->perm_addr, 3);
2368 	memcpy(eui + 5, dev->perm_addr + 3, 3);
2369 	eui[3] = 0xFF;
2370 	eui[4] = 0xFE;
2371 	eui[0] ^= 2;
2372 	return 0;
2373 }
2374 
ipv6_generate_eui64(u8 * eui,struct net_device * dev)2375 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
2376 {
2377 	switch (dev->type) {
2378 	case ARPHRD_ETHER:
2379 	case ARPHRD_FDDI:
2380 		return addrconf_ifid_eui48(eui, dev);
2381 	case ARPHRD_ARCNET:
2382 		return addrconf_ifid_arcnet(eui, dev);
2383 	case ARPHRD_INFINIBAND:
2384 		return addrconf_ifid_infiniband(eui, dev);
2385 	case ARPHRD_SIT:
2386 		return addrconf_ifid_sit(eui, dev);
2387 	case ARPHRD_IPGRE:
2388 	case ARPHRD_TUNNEL:
2389 		return addrconf_ifid_gre(eui, dev);
2390 	case ARPHRD_6LOWPAN:
2391 		return addrconf_ifid_6lowpan(eui, dev);
2392 	case ARPHRD_IEEE1394:
2393 		return addrconf_ifid_ieee1394(eui, dev);
2394 	case ARPHRD_TUNNEL6:
2395 	case ARPHRD_IP6GRE:
2396 	case ARPHRD_RAWIP:
2397 		return addrconf_ifid_ip6tnl(eui, dev);
2398 	}
2399 	return -1;
2400 }
2401 
ipv6_inherit_eui64(u8 * eui,struct inet6_dev * idev)2402 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
2403 {
2404 	int err = -1;
2405 	struct inet6_ifaddr *ifp;
2406 
2407 	read_lock_bh(&idev->lock);
2408 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
2409 		if (ifp->scope > IFA_LINK)
2410 			break;
2411 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
2412 			memcpy(eui, ifp->addr.s6_addr+8, 8);
2413 			err = 0;
2414 			break;
2415 		}
2416 	}
2417 	read_unlock_bh(&idev->lock);
2418 	return err;
2419 }
2420 
2421 /* Generation of a randomized Interface Identifier
2422  * draft-ietf-6man-rfc4941bis, Section 3.3.1
2423  */
2424 
ipv6_gen_rnd_iid(struct in6_addr * addr)2425 static void ipv6_gen_rnd_iid(struct in6_addr *addr)
2426 {
2427 regen:
2428 	get_random_bytes(&addr->s6_addr[8], 8);
2429 
2430 	/* <draft-ietf-6man-rfc4941bis-08.txt>, Section 3.3.1:
2431 	 * check if generated address is not inappropriate:
2432 	 *
2433 	 * - Reserved IPv6 Interface Identifiers
2434 	 * - XXX: already assigned to an address on the device
2435 	 */
2436 
2437 	/* Subnet-router anycast: 0000:0000:0000:0000 */
2438 	if (!(addr->s6_addr32[2] | addr->s6_addr32[3]))
2439 		goto regen;
2440 
2441 	/* IANA Ethernet block: 0200:5EFF:FE00:0000-0200:5EFF:FE00:5212
2442 	 * Proxy Mobile IPv6:   0200:5EFF:FE00:5213
2443 	 * IANA Ethernet block: 0200:5EFF:FE00:5214-0200:5EFF:FEFF:FFFF
2444 	 */
2445 	if (ntohl(addr->s6_addr32[2]) == 0x02005eff &&
2446 	    (ntohl(addr->s6_addr32[3]) & 0Xff000000) == 0xfe000000)
2447 		goto regen;
2448 
2449 	/* Reserved subnet anycast addresses */
2450 	if (ntohl(addr->s6_addr32[2]) == 0xfdffffff &&
2451 	    ntohl(addr->s6_addr32[3]) >= 0Xffffff80)
2452 		goto regen;
2453 }
2454 
2455 /*
2456  *	Add prefix route.
2457  */
2458 
2459 static void
addrconf_prefix_route(struct in6_addr * pfx,int plen,u32 metric,struct net_device * dev,unsigned long expires,u32 flags,gfp_t gfp_flags)2460 addrconf_prefix_route(struct in6_addr *pfx, int plen, u32 metric,
2461 		      struct net_device *dev, unsigned long expires,
2462 		      u32 flags, gfp_t gfp_flags)
2463 {
2464 	struct fib6_config cfg = {
2465 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX,
2466 		.fc_metric = metric ? : IP6_RT_PRIO_ADDRCONF,
2467 		.fc_ifindex = dev->ifindex,
2468 		.fc_expires = expires,
2469 		.fc_dst_len = plen,
2470 		.fc_flags = RTF_UP | flags,
2471 		.fc_nlinfo.nl_net = dev_net(dev),
2472 		.fc_protocol = RTPROT_KERNEL,
2473 		.fc_type = RTN_UNICAST,
2474 	};
2475 
2476 	cfg.fc_dst = *pfx;
2477 
2478 	/* Prevent useless cloning on PtP SIT.
2479 	   This thing is done here expecting that the whole
2480 	   class of non-broadcast devices need not cloning.
2481 	 */
2482 #if IS_ENABLED(CONFIG_IPV6_SIT)
2483 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2484 		cfg.fc_flags |= RTF_NONEXTHOP;
2485 #endif
2486 
2487 	ip6_route_add(&cfg, gfp_flags, NULL);
2488 }
2489 
2490 
addrconf_get_prefix_route(const struct in6_addr * pfx,int plen,const struct net_device * dev,u32 flags,u32 noflags,bool no_gw)2491 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2492 						  int plen,
2493 						  const struct net_device *dev,
2494 						  u32 flags, u32 noflags,
2495 						  bool no_gw)
2496 {
2497 	struct fib6_node *fn;
2498 	struct fib6_info *rt = NULL;
2499 	struct fib6_table *table;
2500 	u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX;
2501 
2502 	table = fib6_get_table(dev_net(dev), tb_id);
2503 	if (!table)
2504 		return NULL;
2505 
2506 	rcu_read_lock();
2507 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0, true);
2508 	if (!fn)
2509 		goto out;
2510 
2511 	for_each_fib6_node_rt_rcu(fn) {
2512 		/* prefix routes only use builtin fib6_nh */
2513 		if (rt->nh)
2514 			continue;
2515 
2516 		if (rt->fib6_nh->fib_nh_dev->ifindex != dev->ifindex)
2517 			continue;
2518 		if (no_gw && rt->fib6_nh->fib_nh_gw_family)
2519 			continue;
2520 		if ((rt->fib6_flags & flags) != flags)
2521 			continue;
2522 		if ((rt->fib6_flags & noflags) != 0)
2523 			continue;
2524 		if (!fib6_info_hold_safe(rt))
2525 			continue;
2526 		break;
2527 	}
2528 out:
2529 	rcu_read_unlock();
2530 	return rt;
2531 }
2532 
2533 
2534 /* Create "default" multicast route to the interface */
2535 
addrconf_add_mroute(struct net_device * dev)2536 static void addrconf_add_mroute(struct net_device *dev)
2537 {
2538 	struct fib6_config cfg = {
2539 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_LOCAL,
2540 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2541 		.fc_ifindex = dev->ifindex,
2542 		.fc_dst_len = 8,
2543 		.fc_flags = RTF_UP,
2544 		.fc_type = RTN_MULTICAST,
2545 		.fc_nlinfo.nl_net = dev_net(dev),
2546 		.fc_protocol = RTPROT_KERNEL,
2547 	};
2548 
2549 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2550 
2551 	ip6_route_add(&cfg, GFP_KERNEL, NULL);
2552 }
2553 
addrconf_add_dev(struct net_device * dev)2554 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2555 {
2556 	struct inet6_dev *idev;
2557 
2558 	ASSERT_RTNL();
2559 
2560 	idev = ipv6_find_idev(dev);
2561 	if (IS_ERR(idev))
2562 		return idev;
2563 
2564 	if (idev->cnf.disable_ipv6)
2565 		return ERR_PTR(-EACCES);
2566 
2567 	/* Add default multicast route */
2568 	if (!(dev->flags & IFF_LOOPBACK) && !netif_is_l3_master(dev))
2569 		addrconf_add_mroute(dev);
2570 
2571 	return idev;
2572 }
2573 
delete_tempaddrs(struct inet6_dev * idev,struct inet6_ifaddr * ifp)2574 static void delete_tempaddrs(struct inet6_dev *idev,
2575 			     struct inet6_ifaddr *ifp)
2576 {
2577 	struct inet6_ifaddr *ift, *tmp;
2578 
2579 	write_lock_bh(&idev->lock);
2580 	list_for_each_entry_safe(ift, tmp, &idev->tempaddr_list, tmp_list) {
2581 		if (ift->ifpub != ifp)
2582 			continue;
2583 
2584 		in6_ifa_hold(ift);
2585 		write_unlock_bh(&idev->lock);
2586 		ipv6_del_addr(ift);
2587 		write_lock_bh(&idev->lock);
2588 	}
2589 	write_unlock_bh(&idev->lock);
2590 }
2591 
manage_tempaddrs(struct inet6_dev * idev,struct inet6_ifaddr * ifp,__u32 valid_lft,__u32 prefered_lft,bool create,unsigned long now)2592 static void manage_tempaddrs(struct inet6_dev *idev,
2593 			     struct inet6_ifaddr *ifp,
2594 			     __u32 valid_lft, __u32 prefered_lft,
2595 			     bool create, unsigned long now)
2596 {
2597 	u32 flags;
2598 	struct inet6_ifaddr *ift;
2599 
2600 	read_lock_bh(&idev->lock);
2601 	/* update all temporary addresses in the list */
2602 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2603 		int age, max_valid, max_prefered;
2604 
2605 		if (ifp != ift->ifpub)
2606 			continue;
2607 
2608 		/* RFC 4941 section 3.3:
2609 		 * If a received option will extend the lifetime of a public
2610 		 * address, the lifetimes of temporary addresses should
2611 		 * be extended, subject to the overall constraint that no
2612 		 * temporary addresses should ever remain "valid" or "preferred"
2613 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2614 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2615 		 */
2616 		age = (now - ift->cstamp) / HZ;
2617 		max_valid = READ_ONCE(idev->cnf.temp_valid_lft) - age;
2618 		if (max_valid < 0)
2619 			max_valid = 0;
2620 
2621 		max_prefered = READ_ONCE(idev->cnf.temp_prefered_lft) -
2622 			       idev->desync_factor - age;
2623 		if (max_prefered < 0)
2624 			max_prefered = 0;
2625 
2626 		if (valid_lft > max_valid)
2627 			valid_lft = max_valid;
2628 
2629 		if (prefered_lft > max_prefered)
2630 			prefered_lft = max_prefered;
2631 
2632 		spin_lock(&ift->lock);
2633 		flags = ift->flags;
2634 		ift->valid_lft = valid_lft;
2635 		ift->prefered_lft = prefered_lft;
2636 		ift->tstamp = now;
2637 		if (prefered_lft > 0)
2638 			ift->flags &= ~IFA_F_DEPRECATED;
2639 
2640 		spin_unlock(&ift->lock);
2641 		if (!(flags&IFA_F_TENTATIVE))
2642 			ipv6_ifa_notify(0, ift);
2643 	}
2644 
2645 	/* Also create a temporary address if it's enabled but no temporary
2646 	 * address currently exists.
2647 	 * However, we get called with valid_lft == 0, prefered_lft == 0, create == false
2648 	 * as part of cleanup (ie. deleting the mngtmpaddr).
2649 	 * We don't want that to result in creating a new temporary ip address.
2650 	 */
2651 	if (list_empty(&idev->tempaddr_list) && (valid_lft || prefered_lft))
2652 		create = true;
2653 
2654 	if (create && READ_ONCE(idev->cnf.use_tempaddr) > 0) {
2655 		/* When a new public address is created as described
2656 		 * in [ADDRCONF], also create a new temporary address.
2657 		 */
2658 		read_unlock_bh(&idev->lock);
2659 		ipv6_create_tempaddr(ifp, false);
2660 	} else {
2661 		read_unlock_bh(&idev->lock);
2662 	}
2663 }
2664 
is_addr_mode_generate_stable(struct inet6_dev * idev)2665 static bool is_addr_mode_generate_stable(struct inet6_dev *idev)
2666 {
2667 	return idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY ||
2668 	       idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_RANDOM;
2669 }
2670 
addrconf_prefix_rcv_add_addr(struct net * net,struct net_device * dev,const struct prefix_info * pinfo,struct inet6_dev * in6_dev,const struct in6_addr * addr,int addr_type,u32 addr_flags,bool sllao,bool tokenized,__u32 valid_lft,u32 prefered_lft)2671 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
2672 				 const struct prefix_info *pinfo,
2673 				 struct inet6_dev *in6_dev,
2674 				 const struct in6_addr *addr, int addr_type,
2675 				 u32 addr_flags, bool sllao, bool tokenized,
2676 				 __u32 valid_lft, u32 prefered_lft)
2677 {
2678 	struct inet6_ifaddr *ifp = ipv6_get_ifaddr(net, addr, dev, 1);
2679 	int create = 0, update_lft = 0;
2680 
2681 	if (!ifp && valid_lft) {
2682 		int max_addresses = READ_ONCE(in6_dev->cnf.max_addresses);
2683 		struct ifa6_config cfg = {
2684 			.pfx = addr,
2685 			.plen = pinfo->prefix_len,
2686 			.ifa_flags = addr_flags,
2687 			.valid_lft = valid_lft,
2688 			.preferred_lft = prefered_lft,
2689 			.scope = addr_type & IPV6_ADDR_SCOPE_MASK,
2690 			.ifa_proto = IFAPROT_KERNEL_RA
2691 		};
2692 
2693 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2694 		if ((READ_ONCE(net->ipv6.devconf_all->optimistic_dad) ||
2695 		     READ_ONCE(in6_dev->cnf.optimistic_dad)) &&
2696 		    !net->ipv6.devconf_all->forwarding && sllao)
2697 			cfg.ifa_flags |= IFA_F_OPTIMISTIC;
2698 #endif
2699 
2700 		/* Do not allow to create too much of autoconfigured
2701 		 * addresses; this would be too easy way to crash kernel.
2702 		 */
2703 		if (!max_addresses ||
2704 		    ipv6_count_addresses(in6_dev) < max_addresses)
2705 			ifp = ipv6_add_addr(in6_dev, &cfg, false, NULL);
2706 
2707 		if (IS_ERR_OR_NULL(ifp))
2708 			return -1;
2709 
2710 		create = 1;
2711 		spin_lock_bh(&ifp->lock);
2712 		ifp->flags |= IFA_F_MANAGETEMPADDR;
2713 		ifp->cstamp = jiffies;
2714 		ifp->tokenized = tokenized;
2715 		spin_unlock_bh(&ifp->lock);
2716 		addrconf_dad_start(ifp);
2717 	}
2718 
2719 	if (ifp) {
2720 		u32 flags;
2721 		unsigned long now;
2722 		u32 stored_lft;
2723 
2724 		/* update lifetime (RFC2462 5.5.3 e) */
2725 		spin_lock_bh(&ifp->lock);
2726 		now = jiffies;
2727 		if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2728 			stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2729 		else
2730 			stored_lft = 0;
2731 
2732 		/* RFC4862 Section 5.5.3e:
2733 		 * "Note that the preferred lifetime of the
2734 		 *  corresponding address is always reset to
2735 		 *  the Preferred Lifetime in the received
2736 		 *  Prefix Information option, regardless of
2737 		 *  whether the valid lifetime is also reset or
2738 		 *  ignored."
2739 		 *
2740 		 * So we should always update prefered_lft here.
2741 		 */
2742 		update_lft = !create && stored_lft;
2743 
2744 		if (update_lft && !READ_ONCE(in6_dev->cnf.ra_honor_pio_life)) {
2745 			const u32 minimum_lft = min_t(u32,
2746 				stored_lft, MIN_VALID_LIFETIME);
2747 			valid_lft = max(valid_lft, minimum_lft);
2748 		}
2749 
2750 		if (update_lft) {
2751 			ifp->valid_lft = valid_lft;
2752 			ifp->prefered_lft = prefered_lft;
2753 			WRITE_ONCE(ifp->tstamp, now);
2754 			flags = ifp->flags;
2755 			ifp->flags &= ~IFA_F_DEPRECATED;
2756 			spin_unlock_bh(&ifp->lock);
2757 
2758 			if (!(flags&IFA_F_TENTATIVE))
2759 				ipv6_ifa_notify(0, ifp);
2760 		} else
2761 			spin_unlock_bh(&ifp->lock);
2762 
2763 		manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2764 				 create, now);
2765 
2766 		in6_ifa_put(ifp);
2767 		addrconf_verify(net);
2768 	}
2769 
2770 	return 0;
2771 }
2772 EXPORT_SYMBOL_GPL(addrconf_prefix_rcv_add_addr);
2773 
addrconf_prefix_rcv(struct net_device * dev,u8 * opt,int len,bool sllao)2774 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2775 {
2776 	struct prefix_info *pinfo;
2777 	struct fib6_table *table;
2778 	__u32 valid_lft;
2779 	__u32 prefered_lft;
2780 	int addr_type, err;
2781 	u32 addr_flags = 0;
2782 	struct inet6_dev *in6_dev;
2783 	struct net *net = dev_net(dev);
2784 	bool ignore_autoconf = false;
2785 
2786 	pinfo = (struct prefix_info *) opt;
2787 
2788 	if (len < sizeof(struct prefix_info)) {
2789 		netdev_dbg(dev, "addrconf: prefix option too short\n");
2790 		return;
2791 	}
2792 
2793 	/*
2794 	 *	Validation checks ([ADDRCONF], page 19)
2795 	 */
2796 
2797 	addr_type = ipv6_addr_type(&pinfo->prefix);
2798 
2799 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2800 		return;
2801 
2802 	valid_lft = ntohl(pinfo->valid);
2803 	prefered_lft = ntohl(pinfo->prefered);
2804 
2805 	if (prefered_lft > valid_lft) {
2806 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2807 		return;
2808 	}
2809 
2810 	in6_dev = in6_dev_get(dev);
2811 
2812 	if (!in6_dev) {
2813 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2814 				    dev->name);
2815 		return;
2816 	}
2817 
2818 	if (valid_lft != 0 && valid_lft < in6_dev->cnf.accept_ra_min_lft)
2819 		goto put;
2820 
2821 	/*
2822 	 *	Two things going on here:
2823 	 *	1) Add routes for on-link prefixes
2824 	 *	2) Configure prefixes with the auto flag set
2825 	 */
2826 
2827 	if (pinfo->onlink) {
2828 		struct fib6_info *rt;
2829 		unsigned long rt_expires;
2830 
2831 		/* Avoid arithmetic overflow. Really, we could
2832 		 * save rt_expires in seconds, likely valid_lft,
2833 		 * but it would require division in fib gc, that it
2834 		 * not good.
2835 		 */
2836 		if (HZ > USER_HZ)
2837 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2838 		else
2839 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2840 
2841 		if (addrconf_finite_timeout(rt_expires))
2842 			rt_expires *= HZ;
2843 
2844 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2845 					       pinfo->prefix_len,
2846 					       dev,
2847 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2848 					       RTF_DEFAULT, true);
2849 
2850 		if (rt) {
2851 			/* Autoconf prefix route */
2852 			if (valid_lft == 0) {
2853 				ip6_del_rt(net, rt, false);
2854 				rt = NULL;
2855 			} else {
2856 				table = rt->fib6_table;
2857 				spin_lock_bh(&table->tb6_lock);
2858 
2859 				if (addrconf_finite_timeout(rt_expires)) {
2860 					/* not infinity */
2861 					fib6_set_expires(rt, jiffies + rt_expires);
2862 					fib6_add_gc_list(rt);
2863 				} else {
2864 					fib6_clean_expires(rt);
2865 					fib6_remove_gc_list(rt);
2866 				}
2867 
2868 				spin_unlock_bh(&table->tb6_lock);
2869 			}
2870 		} else if (valid_lft) {
2871 			clock_t expires = 0;
2872 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2873 			if (addrconf_finite_timeout(rt_expires)) {
2874 				/* not infinity */
2875 				flags |= RTF_EXPIRES;
2876 				expires = jiffies_to_clock_t(rt_expires);
2877 			}
2878 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2879 					      0, dev, expires, flags,
2880 					      GFP_ATOMIC);
2881 		}
2882 		fib6_info_release(rt);
2883 	}
2884 
2885 	/* Try to figure out our local address for this prefix */
2886 
2887 	ignore_autoconf = READ_ONCE(in6_dev->cnf.ra_honor_pio_pflag) && pinfo->preferpd;
2888 	if (pinfo->autoconf && in6_dev->cnf.autoconf && !ignore_autoconf) {
2889 		struct in6_addr addr;
2890 		bool tokenized = false, dev_addr_generated = false;
2891 
2892 		if (pinfo->prefix_len == 64) {
2893 			memcpy(&addr, &pinfo->prefix, 8);
2894 
2895 			if (!ipv6_addr_any(&in6_dev->token)) {
2896 				read_lock_bh(&in6_dev->lock);
2897 				memcpy(addr.s6_addr + 8,
2898 				       in6_dev->token.s6_addr + 8, 8);
2899 				read_unlock_bh(&in6_dev->lock);
2900 				tokenized = true;
2901 			} else if (is_addr_mode_generate_stable(in6_dev) &&
2902 				   !ipv6_generate_stable_address(&addr, 0,
2903 								 in6_dev)) {
2904 				addr_flags |= IFA_F_STABLE_PRIVACY;
2905 				goto ok;
2906 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2907 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2908 				goto put;
2909 			} else {
2910 				dev_addr_generated = true;
2911 			}
2912 			goto ok;
2913 		}
2914 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2915 				    pinfo->prefix_len);
2916 		goto put;
2917 
2918 ok:
2919 		err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
2920 						   &addr, addr_type,
2921 						   addr_flags, sllao,
2922 						   tokenized, valid_lft,
2923 						   prefered_lft);
2924 		if (err)
2925 			goto put;
2926 
2927 		/* Ignore error case here because previous prefix add addr was
2928 		 * successful which will be notified.
2929 		 */
2930 		ndisc_ops_prefix_rcv_add_addr(net, dev, pinfo, in6_dev, &addr,
2931 					      addr_type, addr_flags, sllao,
2932 					      tokenized, valid_lft,
2933 					      prefered_lft,
2934 					      dev_addr_generated);
2935 	}
2936 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2937 put:
2938 	in6_dev_put(in6_dev);
2939 }
2940 
addrconf_set_sit_dstaddr(struct net * net,struct net_device * dev,struct in6_ifreq * ireq)2941 static int addrconf_set_sit_dstaddr(struct net *net, struct net_device *dev,
2942 		struct in6_ifreq *ireq)
2943 {
2944 	struct ip_tunnel_parm_kern p = { };
2945 	int err;
2946 
2947 	if (!(ipv6_addr_type(&ireq->ifr6_addr) & IPV6_ADDR_COMPATv4))
2948 		return -EADDRNOTAVAIL;
2949 
2950 	p.iph.daddr = ireq->ifr6_addr.s6_addr32[3];
2951 	p.iph.version = 4;
2952 	p.iph.ihl = 5;
2953 	p.iph.protocol = IPPROTO_IPV6;
2954 	p.iph.ttl = 64;
2955 
2956 	if (!dev->netdev_ops->ndo_tunnel_ctl)
2957 		return -EOPNOTSUPP;
2958 	err = dev->netdev_ops->ndo_tunnel_ctl(dev, &p, SIOCADDTUNNEL);
2959 	if (err)
2960 		return err;
2961 
2962 	dev = __dev_get_by_name(net, p.name);
2963 	if (!dev)
2964 		return -ENOBUFS;
2965 	return dev_open(dev, NULL);
2966 }
2967 
2968 /*
2969  *	Set destination address.
2970  *	Special case for SIT interfaces where we create a new "virtual"
2971  *	device.
2972  */
addrconf_set_dstaddr(struct net * net,void __user * arg)2973 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2974 {
2975 	struct net_device *dev;
2976 	struct in6_ifreq ireq;
2977 	int err = -ENODEV;
2978 
2979 	if (!IS_ENABLED(CONFIG_IPV6_SIT))
2980 		return -ENODEV;
2981 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2982 		return -EFAULT;
2983 
2984 	rtnl_net_lock(net);
2985 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2986 	if (dev && dev->type == ARPHRD_SIT)
2987 		err = addrconf_set_sit_dstaddr(net, dev, &ireq);
2988 	rtnl_net_unlock(net);
2989 	return err;
2990 }
2991 
ipv6_mc_config(struct sock * sk,bool join,const struct in6_addr * addr,int ifindex)2992 static int ipv6_mc_config(struct sock *sk, bool join,
2993 			  const struct in6_addr *addr, int ifindex)
2994 {
2995 	int ret;
2996 
2997 	ASSERT_RTNL();
2998 
2999 	lock_sock(sk);
3000 	if (join)
3001 		ret = ipv6_sock_mc_join(sk, ifindex, addr);
3002 	else
3003 		ret = ipv6_sock_mc_drop(sk, ifindex, addr);
3004 	release_sock(sk);
3005 
3006 	return ret;
3007 }
3008 
3009 /*
3010  *	Manual configuration of address on an interface
3011  */
inet6_addr_add(struct net * net,struct net_device * dev,struct ifa6_config * cfg,clock_t expires,u32 flags,struct netlink_ext_ack * extack)3012 static int inet6_addr_add(struct net *net, struct net_device *dev,
3013 			  struct ifa6_config *cfg, clock_t expires, u32 flags,
3014 			  struct netlink_ext_ack *extack)
3015 {
3016 	struct inet6_ifaddr *ifp;
3017 	struct inet6_dev *idev;
3018 
3019 	ASSERT_RTNL_NET(net);
3020 
3021 	if (cfg->plen > 128) {
3022 		NL_SET_ERR_MSG_MOD(extack, "Invalid prefix length");
3023 		return -EINVAL;
3024 	}
3025 
3026 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR && cfg->plen != 64) {
3027 		NL_SET_ERR_MSG_MOD(extack, "address with \"mngtmpaddr\" flag must have a prefix length of 64");
3028 		return -EINVAL;
3029 	}
3030 
3031 	idev = addrconf_add_dev(dev);
3032 	if (IS_ERR(idev)) {
3033 		NL_SET_ERR_MSG_MOD(extack, "IPv6 is disabled on this device");
3034 		return PTR_ERR(idev);
3035 	}
3036 
3037 	if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
3038 		int ret = ipv6_mc_config(net->ipv6.mc_autojoin_sk,
3039 					 true, cfg->pfx, dev->ifindex);
3040 
3041 		if (ret < 0) {
3042 			NL_SET_ERR_MSG_MOD(extack, "Multicast auto join failed");
3043 			return ret;
3044 		}
3045 	}
3046 
3047 	cfg->scope = ipv6_addr_scope(cfg->pfx);
3048 
3049 	ifp = ipv6_add_addr(idev, cfg, true, extack);
3050 	if (!IS_ERR(ifp)) {
3051 		if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
3052 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3053 					      ifp->rt_priority, dev, expires,
3054 					      flags, GFP_KERNEL);
3055 		}
3056 
3057 		/* Send a netlink notification if DAD is enabled and
3058 		 * optimistic flag is not set
3059 		 */
3060 		if (!(ifp->flags & (IFA_F_OPTIMISTIC | IFA_F_NODAD)))
3061 			ipv6_ifa_notify(0, ifp);
3062 		/*
3063 		 * Note that section 3.1 of RFC 4429 indicates
3064 		 * that the Optimistic flag should not be set for
3065 		 * manually configured addresses
3066 		 */
3067 		addrconf_dad_start(ifp);
3068 		if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR)
3069 			manage_tempaddrs(idev, ifp, cfg->valid_lft,
3070 					 cfg->preferred_lft, true, jiffies);
3071 		in6_ifa_put(ifp);
3072 		addrconf_verify_rtnl(net);
3073 		return 0;
3074 	} else if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
3075 		ipv6_mc_config(net->ipv6.mc_autojoin_sk, false,
3076 			       cfg->pfx, dev->ifindex);
3077 	}
3078 
3079 	return PTR_ERR(ifp);
3080 }
3081 
inet6_addr_del(struct net * net,int ifindex,u32 ifa_flags,const struct in6_addr * pfx,unsigned int plen,struct netlink_ext_ack * extack)3082 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
3083 			  const struct in6_addr *pfx, unsigned int plen,
3084 			  struct netlink_ext_ack *extack)
3085 {
3086 	struct inet6_ifaddr *ifp;
3087 	struct inet6_dev *idev;
3088 	struct net_device *dev;
3089 
3090 	if (plen > 128) {
3091 		NL_SET_ERR_MSG_MOD(extack, "Invalid prefix length");
3092 		return -EINVAL;
3093 	}
3094 
3095 	dev = __dev_get_by_index(net, ifindex);
3096 	if (!dev) {
3097 		NL_SET_ERR_MSG_MOD(extack, "Unable to find the interface");
3098 		return -ENODEV;
3099 	}
3100 
3101 	idev = __in6_dev_get_rtnl_net(dev);
3102 	if (!idev) {
3103 		NL_SET_ERR_MSG_MOD(extack, "IPv6 is disabled on this device");
3104 		return -ENXIO;
3105 	}
3106 
3107 	read_lock_bh(&idev->lock);
3108 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
3109 		if (ifp->prefix_len == plen &&
3110 		    ipv6_addr_equal(pfx, &ifp->addr)) {
3111 			in6_ifa_hold(ifp);
3112 			read_unlock_bh(&idev->lock);
3113 
3114 			ipv6_del_addr(ifp);
3115 
3116 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
3117 			    (ifp->flags & IFA_F_MANAGETEMPADDR))
3118 				delete_tempaddrs(idev, ifp);
3119 
3120 			addrconf_verify_rtnl(net);
3121 			if (ipv6_addr_is_multicast(pfx)) {
3122 				ipv6_mc_config(net->ipv6.mc_autojoin_sk,
3123 					       false, pfx, dev->ifindex);
3124 			}
3125 			return 0;
3126 		}
3127 	}
3128 	read_unlock_bh(&idev->lock);
3129 
3130 	NL_SET_ERR_MSG_MOD(extack, "address not found");
3131 	return -EADDRNOTAVAIL;
3132 }
3133 
3134 
addrconf_add_ifaddr(struct net * net,void __user * arg)3135 int addrconf_add_ifaddr(struct net *net, void __user *arg)
3136 {
3137 	struct ifa6_config cfg = {
3138 		.ifa_flags = IFA_F_PERMANENT,
3139 		.preferred_lft = INFINITY_LIFE_TIME,
3140 		.valid_lft = INFINITY_LIFE_TIME,
3141 	};
3142 	struct net_device *dev;
3143 	struct in6_ifreq ireq;
3144 	int err;
3145 
3146 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3147 		return -EPERM;
3148 
3149 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3150 		return -EFAULT;
3151 
3152 	cfg.pfx = &ireq.ifr6_addr;
3153 	cfg.plen = ireq.ifr6_prefixlen;
3154 
3155 	rtnl_net_lock(net);
3156 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
3157 	if (dev) {
3158 		netdev_lock_ops(dev);
3159 		err = inet6_addr_add(net, dev, &cfg, 0, 0, NULL);
3160 		netdev_unlock_ops(dev);
3161 	} else {
3162 		err = -ENODEV;
3163 	}
3164 	rtnl_net_unlock(net);
3165 	return err;
3166 }
3167 
addrconf_del_ifaddr(struct net * net,void __user * arg)3168 int addrconf_del_ifaddr(struct net *net, void __user *arg)
3169 {
3170 	struct in6_ifreq ireq;
3171 	int err;
3172 
3173 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3174 		return -EPERM;
3175 
3176 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3177 		return -EFAULT;
3178 
3179 	rtnl_net_lock(net);
3180 	err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
3181 			     ireq.ifr6_prefixlen, NULL);
3182 	rtnl_net_unlock(net);
3183 	return err;
3184 }
3185 
add_addr(struct inet6_dev * idev,const struct in6_addr * addr,int plen,int scope,u8 proto)3186 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
3187 		     int plen, int scope, u8 proto)
3188 {
3189 	struct inet6_ifaddr *ifp;
3190 	struct ifa6_config cfg = {
3191 		.pfx = addr,
3192 		.plen = plen,
3193 		.ifa_flags = IFA_F_PERMANENT,
3194 		.valid_lft = INFINITY_LIFE_TIME,
3195 		.preferred_lft = INFINITY_LIFE_TIME,
3196 		.scope = scope,
3197 		.ifa_proto = proto
3198 	};
3199 
3200 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3201 	if (!IS_ERR(ifp)) {
3202 		spin_lock_bh(&ifp->lock);
3203 		ifp->flags &= ~IFA_F_TENTATIVE;
3204 		spin_unlock_bh(&ifp->lock);
3205 		rt_genid_bump_ipv6(dev_net(idev->dev));
3206 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3207 		in6_ifa_put(ifp);
3208 	}
3209 }
3210 
3211 #if IS_ENABLED(CONFIG_IPV6_SIT) || IS_ENABLED(CONFIG_NET_IPGRE) || IS_ENABLED(CONFIG_IPV6_GRE)
add_v4_addrs(struct inet6_dev * idev)3212 static void add_v4_addrs(struct inet6_dev *idev)
3213 {
3214 	struct in6_addr addr;
3215 	struct net_device *dev;
3216 	struct net *net = dev_net(idev->dev);
3217 	int scope, plen;
3218 	u32 pflags = 0;
3219 
3220 	ASSERT_RTNL();
3221 
3222 	memset(&addr, 0, sizeof(struct in6_addr));
3223 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
3224 
3225 	if (!(idev->dev->flags & IFF_POINTOPOINT) && idev->dev->type == ARPHRD_SIT) {
3226 		scope = IPV6_ADDR_COMPATv4;
3227 		plen = 96;
3228 		pflags |= RTF_NONEXTHOP;
3229 	} else {
3230 		if (idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_NONE)
3231 			return;
3232 
3233 		addr.s6_addr32[0] = htonl(0xfe800000);
3234 		scope = IFA_LINK;
3235 		plen = 64;
3236 	}
3237 
3238 	if (addr.s6_addr32[3]) {
3239 		add_addr(idev, &addr, plen, scope, IFAPROT_UNSPEC);
3240 		addrconf_prefix_route(&addr, plen, 0, idev->dev, 0, pflags,
3241 				      GFP_KERNEL);
3242 		return;
3243 	}
3244 
3245 	for_each_netdev(net, dev) {
3246 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
3247 		if (in_dev && (dev->flags & IFF_UP)) {
3248 			struct in_ifaddr *ifa;
3249 			int flag = scope;
3250 
3251 			in_dev_for_each_ifa_rtnl(ifa, in_dev) {
3252 				addr.s6_addr32[3] = ifa->ifa_local;
3253 
3254 				if (ifa->ifa_scope == RT_SCOPE_LINK)
3255 					continue;
3256 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
3257 					if (idev->dev->flags&IFF_POINTOPOINT)
3258 						continue;
3259 					flag |= IFA_HOST;
3260 				}
3261 
3262 				add_addr(idev, &addr, plen, flag,
3263 					 IFAPROT_UNSPEC);
3264 				addrconf_prefix_route(&addr, plen, 0, idev->dev,
3265 						      0, pflags, GFP_KERNEL);
3266 			}
3267 		}
3268 	}
3269 }
3270 #endif
3271 
init_loopback(struct net_device * dev)3272 static void init_loopback(struct net_device *dev)
3273 {
3274 	struct inet6_dev  *idev;
3275 
3276 	/* ::1 */
3277 
3278 	ASSERT_RTNL();
3279 
3280 	idev = ipv6_find_idev(dev);
3281 	if (IS_ERR(idev)) {
3282 		pr_debug("%s: add_dev failed\n", __func__);
3283 		return;
3284 	}
3285 
3286 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST, IFAPROT_KERNEL_LO);
3287 }
3288 
addrconf_add_linklocal(struct inet6_dev * idev,const struct in6_addr * addr,u32 flags)3289 void addrconf_add_linklocal(struct inet6_dev *idev,
3290 			    const struct in6_addr *addr, u32 flags)
3291 {
3292 	struct ifa6_config cfg = {
3293 		.pfx = addr,
3294 		.plen = 64,
3295 		.ifa_flags = flags | IFA_F_PERMANENT,
3296 		.valid_lft = INFINITY_LIFE_TIME,
3297 		.preferred_lft = INFINITY_LIFE_TIME,
3298 		.scope = IFA_LINK,
3299 		.ifa_proto = IFAPROT_KERNEL_LL
3300 	};
3301 	struct inet6_ifaddr *ifp;
3302 
3303 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
3304 	if ((READ_ONCE(dev_net(idev->dev)->ipv6.devconf_all->optimistic_dad) ||
3305 	     READ_ONCE(idev->cnf.optimistic_dad)) &&
3306 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
3307 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
3308 #endif
3309 
3310 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3311 	if (!IS_ERR(ifp)) {
3312 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, 0, idev->dev,
3313 				      0, 0, GFP_ATOMIC);
3314 		addrconf_dad_start(ifp);
3315 		in6_ifa_put(ifp);
3316 	}
3317 }
3318 EXPORT_SYMBOL_GPL(addrconf_add_linklocal);
3319 
ipv6_reserved_interfaceid(struct in6_addr address)3320 static bool ipv6_reserved_interfaceid(struct in6_addr address)
3321 {
3322 	if ((address.s6_addr32[2] | address.s6_addr32[3]) == 0)
3323 		return true;
3324 
3325 	if (address.s6_addr32[2] == htonl(0x02005eff) &&
3326 	    ((address.s6_addr32[3] & htonl(0xfe000000)) == htonl(0xfe000000)))
3327 		return true;
3328 
3329 	if (address.s6_addr32[2] == htonl(0xfdffffff) &&
3330 	    ((address.s6_addr32[3] & htonl(0xffffff80)) == htonl(0xffffff80)))
3331 		return true;
3332 
3333 	return false;
3334 }
3335 
ipv6_generate_stable_address(struct in6_addr * address,u8 dad_count,const struct inet6_dev * idev)3336 static int ipv6_generate_stable_address(struct in6_addr *address,
3337 					u8 dad_count,
3338 					const struct inet6_dev *idev)
3339 {
3340 	static DEFINE_SPINLOCK(lock);
3341 	static __u32 digest[SHA1_DIGEST_WORDS];
3342 	static __u32 workspace[SHA1_WORKSPACE_WORDS];
3343 
3344 	static union {
3345 		char __data[SHA1_BLOCK_SIZE];
3346 		struct {
3347 			struct in6_addr secret;
3348 			__be32 prefix[2];
3349 			unsigned char hwaddr[MAX_ADDR_LEN];
3350 			u8 dad_count;
3351 		} __packed;
3352 	} data;
3353 
3354 	struct in6_addr secret;
3355 	struct in6_addr temp;
3356 	struct net *net = dev_net(idev->dev);
3357 
3358 	BUILD_BUG_ON(sizeof(data.__data) != sizeof(data));
3359 
3360 	if (idev->cnf.stable_secret.initialized)
3361 		secret = idev->cnf.stable_secret.secret;
3362 	else if (net->ipv6.devconf_dflt->stable_secret.initialized)
3363 		secret = net->ipv6.devconf_dflt->stable_secret.secret;
3364 	else
3365 		return -1;
3366 
3367 retry:
3368 	spin_lock_bh(&lock);
3369 
3370 	sha1_init(digest);
3371 	memset(&data, 0, sizeof(data));
3372 	memset(workspace, 0, sizeof(workspace));
3373 	memcpy(data.hwaddr, idev->dev->perm_addr, idev->dev->addr_len);
3374 	data.prefix[0] = address->s6_addr32[0];
3375 	data.prefix[1] = address->s6_addr32[1];
3376 	data.secret = secret;
3377 	data.dad_count = dad_count;
3378 
3379 	sha1_transform(digest, data.__data, workspace);
3380 
3381 	temp = *address;
3382 	temp.s6_addr32[2] = (__force __be32)digest[0];
3383 	temp.s6_addr32[3] = (__force __be32)digest[1];
3384 
3385 	spin_unlock_bh(&lock);
3386 
3387 	if (ipv6_reserved_interfaceid(temp)) {
3388 		dad_count++;
3389 		if (dad_count > dev_net(idev->dev)->ipv6.sysctl.idgen_retries)
3390 			return -1;
3391 		goto retry;
3392 	}
3393 
3394 	*address = temp;
3395 	return 0;
3396 }
3397 
ipv6_gen_mode_random_init(struct inet6_dev * idev)3398 static void ipv6_gen_mode_random_init(struct inet6_dev *idev)
3399 {
3400 	struct ipv6_stable_secret *s = &idev->cnf.stable_secret;
3401 
3402 	if (s->initialized)
3403 		return;
3404 	s = &idev->cnf.stable_secret;
3405 	get_random_bytes(&s->secret, sizeof(s->secret));
3406 	s->initialized = true;
3407 }
3408 
addrconf_addr_gen(struct inet6_dev * idev,bool prefix_route)3409 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
3410 {
3411 	struct in6_addr addr;
3412 
3413 	/* no link local addresses on L3 master devices */
3414 	if (netif_is_l3_master(idev->dev))
3415 		return;
3416 
3417 	/* no link local addresses on devices flagged as slaves */
3418 	if (idev->dev->priv_flags & IFF_NO_ADDRCONF)
3419 		return;
3420 
3421 	ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
3422 
3423 	switch (idev->cnf.addr_gen_mode) {
3424 	case IN6_ADDR_GEN_MODE_RANDOM:
3425 		ipv6_gen_mode_random_init(idev);
3426 		fallthrough;
3427 	case IN6_ADDR_GEN_MODE_STABLE_PRIVACY:
3428 		if (!ipv6_generate_stable_address(&addr, 0, idev))
3429 			addrconf_add_linklocal(idev, &addr,
3430 					       IFA_F_STABLE_PRIVACY);
3431 		else if (prefix_route)
3432 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3433 					      0, 0, GFP_KERNEL);
3434 		break;
3435 	case IN6_ADDR_GEN_MODE_EUI64:
3436 		/* addrconf_add_linklocal also adds a prefix_route and we
3437 		 * only need to care about prefix routes if ipv6_generate_eui64
3438 		 * couldn't generate one.
3439 		 */
3440 		if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
3441 			addrconf_add_linklocal(idev, &addr, 0);
3442 		else if (prefix_route)
3443 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3444 					      0, 0, GFP_KERNEL);
3445 		break;
3446 	case IN6_ADDR_GEN_MODE_NONE:
3447 	default:
3448 		/* will not add any link local address */
3449 		break;
3450 	}
3451 }
3452 
addrconf_dev_config(struct net_device * dev)3453 static void addrconf_dev_config(struct net_device *dev)
3454 {
3455 	struct inet6_dev *idev;
3456 
3457 	ASSERT_RTNL();
3458 
3459 	if ((dev->type != ARPHRD_ETHER) &&
3460 	    (dev->type != ARPHRD_FDDI) &&
3461 	    (dev->type != ARPHRD_ARCNET) &&
3462 	    (dev->type != ARPHRD_INFINIBAND) &&
3463 	    (dev->type != ARPHRD_IEEE1394) &&
3464 	    (dev->type != ARPHRD_TUNNEL6) &&
3465 	    (dev->type != ARPHRD_6LOWPAN) &&
3466 	    (dev->type != ARPHRD_TUNNEL) &&
3467 	    (dev->type != ARPHRD_NONE) &&
3468 	    (dev->type != ARPHRD_RAWIP)) {
3469 		/* Alas, we support only Ethernet autoconfiguration. */
3470 		idev = __in6_dev_get(dev);
3471 		if (!IS_ERR_OR_NULL(idev) && dev->flags & IFF_UP &&
3472 		    dev->flags & IFF_MULTICAST)
3473 			ipv6_mc_up(idev);
3474 		return;
3475 	}
3476 
3477 	idev = addrconf_add_dev(dev);
3478 	if (IS_ERR(idev))
3479 		return;
3480 
3481 	/* this device type has no EUI support */
3482 	if (dev->type == ARPHRD_NONE &&
3483 	    idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)
3484 		WRITE_ONCE(idev->cnf.addr_gen_mode,
3485 			   IN6_ADDR_GEN_MODE_RANDOM);
3486 
3487 	addrconf_addr_gen(idev, false);
3488 }
3489 
3490 #if IS_ENABLED(CONFIG_IPV6_SIT)
addrconf_sit_config(struct net_device * dev)3491 static void addrconf_sit_config(struct net_device *dev)
3492 {
3493 	struct inet6_dev *idev;
3494 
3495 	ASSERT_RTNL();
3496 
3497 	/*
3498 	 * Configure the tunnel with one of our IPv4
3499 	 * addresses... we should configure all of
3500 	 * our v4 addrs in the tunnel
3501 	 */
3502 
3503 	idev = ipv6_find_idev(dev);
3504 	if (IS_ERR(idev)) {
3505 		pr_debug("%s: add_dev failed\n", __func__);
3506 		return;
3507 	}
3508 
3509 	if (dev->priv_flags & IFF_ISATAP) {
3510 		addrconf_addr_gen(idev, false);
3511 		return;
3512 	}
3513 
3514 	add_v4_addrs(idev);
3515 
3516 	if (dev->flags&IFF_POINTOPOINT)
3517 		addrconf_add_mroute(dev);
3518 }
3519 #endif
3520 
3521 #if IS_ENABLED(CONFIG_NET_IPGRE) || IS_ENABLED(CONFIG_IPV6_GRE)
addrconf_gre_config(struct net_device * dev)3522 static void addrconf_gre_config(struct net_device *dev)
3523 {
3524 	struct inet6_dev *idev;
3525 
3526 	ASSERT_RTNL();
3527 
3528 	idev = ipv6_find_idev(dev);
3529 	if (IS_ERR(idev)) {
3530 		pr_debug("%s: add_dev failed\n", __func__);
3531 		return;
3532 	}
3533 
3534 	/* Generate the IPv6 link-local address using addrconf_addr_gen(),
3535 	 * unless we have an IPv4 GRE device not bound to an IP address and
3536 	 * which is in EUI64 mode (as __ipv6_isatap_ifid() would fail in this
3537 	 * case). Such devices fall back to add_v4_addrs() instead.
3538 	 */
3539 	if (!(dev->type == ARPHRD_IPGRE && *(__be32 *)dev->dev_addr == 0 &&
3540 	      idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)) {
3541 		addrconf_addr_gen(idev, true);
3542 		return;
3543 	}
3544 
3545 	add_v4_addrs(idev);
3546 
3547 	if (dev->flags & IFF_POINTOPOINT)
3548 		addrconf_add_mroute(dev);
3549 }
3550 #endif
3551 
addrconf_init_auto_addrs(struct net_device * dev)3552 static void addrconf_init_auto_addrs(struct net_device *dev)
3553 {
3554 	switch (dev->type) {
3555 #if IS_ENABLED(CONFIG_IPV6_SIT)
3556 	case ARPHRD_SIT:
3557 		addrconf_sit_config(dev);
3558 		break;
3559 #endif
3560 #if IS_ENABLED(CONFIG_NET_IPGRE) || IS_ENABLED(CONFIG_IPV6_GRE)
3561 	case ARPHRD_IP6GRE:
3562 	case ARPHRD_IPGRE:
3563 		addrconf_gre_config(dev);
3564 		break;
3565 #endif
3566 	case ARPHRD_LOOPBACK:
3567 		init_loopback(dev);
3568 		break;
3569 
3570 	default:
3571 		addrconf_dev_config(dev);
3572 		break;
3573 	}
3574 }
3575 
fixup_permanent_addr(struct net * net,struct inet6_dev * idev,struct inet6_ifaddr * ifp)3576 static int fixup_permanent_addr(struct net *net,
3577 				struct inet6_dev *idev,
3578 				struct inet6_ifaddr *ifp)
3579 {
3580 	/* !fib6_node means the host route was removed from the
3581 	 * FIB, for example, if 'lo' device is taken down. In that
3582 	 * case regenerate the host route.
3583 	 */
3584 	if (!ifp->rt || !ifp->rt->fib6_node) {
3585 		struct fib6_info *f6i, *prev;
3586 
3587 		f6i = addrconf_f6i_alloc(net, idev, &ifp->addr, false,
3588 					 GFP_ATOMIC, NULL);
3589 		if (IS_ERR(f6i))
3590 			return PTR_ERR(f6i);
3591 
3592 		/* ifp->rt can be accessed outside of rtnl */
3593 		spin_lock(&ifp->lock);
3594 		prev = ifp->rt;
3595 		ifp->rt = f6i;
3596 		spin_unlock(&ifp->lock);
3597 
3598 		fib6_info_release(prev);
3599 	}
3600 
3601 	if (!(ifp->flags & IFA_F_NOPREFIXROUTE)) {
3602 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3603 				      ifp->rt_priority, idev->dev, 0, 0,
3604 				      GFP_ATOMIC);
3605 	}
3606 
3607 	if (ifp->state == INET6_IFADDR_STATE_PREDAD)
3608 		addrconf_dad_start(ifp);
3609 
3610 	return 0;
3611 }
3612 
addrconf_permanent_addr(struct net * net,struct net_device * dev)3613 static void addrconf_permanent_addr(struct net *net, struct net_device *dev)
3614 {
3615 	struct inet6_ifaddr *ifp, *tmp;
3616 	struct inet6_dev *idev;
3617 
3618 	idev = __in6_dev_get(dev);
3619 	if (!idev)
3620 		return;
3621 
3622 	write_lock_bh(&idev->lock);
3623 
3624 	list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
3625 		if ((ifp->flags & IFA_F_PERMANENT) &&
3626 		    fixup_permanent_addr(net, idev, ifp) < 0) {
3627 			write_unlock_bh(&idev->lock);
3628 			in6_ifa_hold(ifp);
3629 			ipv6_del_addr(ifp);
3630 			write_lock_bh(&idev->lock);
3631 
3632 			net_info_ratelimited("%s: Failed to add prefix route for address %pI6c; dropping\n",
3633 					     idev->dev->name, &ifp->addr);
3634 		}
3635 	}
3636 
3637 	write_unlock_bh(&idev->lock);
3638 }
3639 
addrconf_notify(struct notifier_block * this,unsigned long event,void * ptr)3640 static int addrconf_notify(struct notifier_block *this, unsigned long event,
3641 			   void *ptr)
3642 {
3643 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3644 	struct netdev_notifier_change_info *change_info;
3645 	struct netdev_notifier_changeupper_info *info;
3646 	struct inet6_dev *idev = __in6_dev_get(dev);
3647 	struct net *net = dev_net(dev);
3648 	int run_pending = 0;
3649 	int err;
3650 
3651 	switch (event) {
3652 	case NETDEV_REGISTER:
3653 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3654 			idev = ipv6_add_dev(dev);
3655 			if (IS_ERR(idev))
3656 				return notifier_from_errno(PTR_ERR(idev));
3657 		}
3658 		break;
3659 
3660 	case NETDEV_CHANGEMTU:
3661 		/* if MTU under IPV6_MIN_MTU stop IPv6 on this interface. */
3662 		if (dev->mtu < IPV6_MIN_MTU) {
3663 			addrconf_ifdown(dev, dev != net->loopback_dev);
3664 			break;
3665 		}
3666 
3667 		if (idev) {
3668 			rt6_mtu_change(dev, dev->mtu);
3669 			WRITE_ONCE(idev->cnf.mtu6, dev->mtu);
3670 			break;
3671 		}
3672 
3673 		/* allocate new idev */
3674 		idev = ipv6_add_dev(dev);
3675 		if (IS_ERR(idev))
3676 			break;
3677 
3678 		/* device is still not ready */
3679 		if (!(idev->if_flags & IF_READY))
3680 			break;
3681 
3682 		run_pending = 1;
3683 		fallthrough;
3684 	case NETDEV_UP:
3685 	case NETDEV_CHANGE:
3686 		if (idev && idev->cnf.disable_ipv6)
3687 			break;
3688 
3689 		if (dev->priv_flags & IFF_NO_ADDRCONF) {
3690 			if (event == NETDEV_UP && !IS_ERR_OR_NULL(idev) &&
3691 			    dev->flags & IFF_UP && dev->flags & IFF_MULTICAST)
3692 				ipv6_mc_up(idev);
3693 			break;
3694 		}
3695 
3696 		if (event == NETDEV_UP) {
3697 			/* restore routes for permanent addresses */
3698 			addrconf_permanent_addr(net, dev);
3699 
3700 			if (!addrconf_link_ready(dev)) {
3701 				/* device is not ready yet. */
3702 				pr_debug("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
3703 					 dev->name);
3704 				break;
3705 			}
3706 
3707 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
3708 				idev = ipv6_add_dev(dev);
3709 
3710 			if (!IS_ERR_OR_NULL(idev)) {
3711 				idev->if_flags |= IF_READY;
3712 				run_pending = 1;
3713 			}
3714 		} else if (event == NETDEV_CHANGE) {
3715 			if (!addrconf_link_ready(dev)) {
3716 				/* device is still not ready. */
3717 				rt6_sync_down_dev(dev, event);
3718 				break;
3719 			}
3720 
3721 			if (!IS_ERR_OR_NULL(idev)) {
3722 				if (idev->if_flags & IF_READY) {
3723 					/* device is already configured -
3724 					 * but resend MLD reports, we might
3725 					 * have roamed and need to update
3726 					 * multicast snooping switches
3727 					 */
3728 					ipv6_mc_up(idev);
3729 					change_info = ptr;
3730 					if (change_info->flags_changed & IFF_NOARP)
3731 						addrconf_dad_run(idev, true);
3732 					rt6_sync_up(dev, RTNH_F_LINKDOWN);
3733 					break;
3734 				}
3735 				idev->if_flags |= IF_READY;
3736 			}
3737 
3738 			pr_debug("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
3739 				 dev->name);
3740 
3741 			run_pending = 1;
3742 		}
3743 
3744 		addrconf_init_auto_addrs(dev);
3745 
3746 		if (!IS_ERR_OR_NULL(idev)) {
3747 			if (run_pending)
3748 				addrconf_dad_run(idev, false);
3749 
3750 			/* Device has an address by now */
3751 			rt6_sync_up(dev, RTNH_F_DEAD);
3752 
3753 			/*
3754 			 * If the MTU changed during the interface down,
3755 			 * when the interface up, the changed MTU must be
3756 			 * reflected in the idev as well as routers.
3757 			 */
3758 			if (idev->cnf.mtu6 != dev->mtu &&
3759 			    dev->mtu >= IPV6_MIN_MTU) {
3760 				rt6_mtu_change(dev, dev->mtu);
3761 				WRITE_ONCE(idev->cnf.mtu6, dev->mtu);
3762 			}
3763 			WRITE_ONCE(idev->tstamp, jiffies);
3764 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
3765 
3766 			/*
3767 			 * If the changed mtu during down is lower than
3768 			 * IPV6_MIN_MTU stop IPv6 on this interface.
3769 			 */
3770 			if (dev->mtu < IPV6_MIN_MTU)
3771 				addrconf_ifdown(dev, dev != net->loopback_dev);
3772 		}
3773 		break;
3774 
3775 	case NETDEV_DOWN:
3776 	case NETDEV_UNREGISTER:
3777 		/*
3778 		 *	Remove all addresses from this interface.
3779 		 */
3780 		addrconf_ifdown(dev, event != NETDEV_DOWN);
3781 		break;
3782 
3783 	case NETDEV_CHANGENAME:
3784 		if (idev) {
3785 			snmp6_unregister_dev(idev);
3786 			addrconf_sysctl_unregister(idev);
3787 			err = addrconf_sysctl_register(idev);
3788 			if (err)
3789 				return notifier_from_errno(err);
3790 			err = snmp6_register_dev(idev);
3791 			if (err) {
3792 				addrconf_sysctl_unregister(idev);
3793 				return notifier_from_errno(err);
3794 			}
3795 		}
3796 		break;
3797 
3798 	case NETDEV_PRE_TYPE_CHANGE:
3799 	case NETDEV_POST_TYPE_CHANGE:
3800 		if (idev)
3801 			addrconf_type_change(dev, event);
3802 		break;
3803 
3804 	case NETDEV_CHANGEUPPER:
3805 		info = ptr;
3806 
3807 		/* flush all routes if dev is linked to or unlinked from
3808 		 * an L3 master device (e.g., VRF)
3809 		 */
3810 		if (info->upper_dev && netif_is_l3_master(info->upper_dev))
3811 			addrconf_ifdown(dev, false);
3812 	}
3813 
3814 	return NOTIFY_OK;
3815 }
3816 
3817 /*
3818  *	addrconf module should be notified of a device going up
3819  */
3820 static struct notifier_block ipv6_dev_notf = {
3821 	.notifier_call = addrconf_notify,
3822 	.priority = ADDRCONF_NOTIFY_PRIORITY,
3823 };
3824 
addrconf_type_change(struct net_device * dev,unsigned long event)3825 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3826 {
3827 	struct inet6_dev *idev;
3828 	ASSERT_RTNL();
3829 
3830 	idev = __in6_dev_get(dev);
3831 
3832 	if (event == NETDEV_POST_TYPE_CHANGE)
3833 		ipv6_mc_remap(idev);
3834 	else if (event == NETDEV_PRE_TYPE_CHANGE)
3835 		ipv6_mc_unmap(idev);
3836 }
3837 
addr_is_local(const struct in6_addr * addr)3838 static bool addr_is_local(const struct in6_addr *addr)
3839 {
3840 	return ipv6_addr_type(addr) &
3841 		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
3842 }
3843 
addrconf_ifdown(struct net_device * dev,bool unregister)3844 static int addrconf_ifdown(struct net_device *dev, bool unregister)
3845 {
3846 	unsigned long event = unregister ? NETDEV_UNREGISTER : NETDEV_DOWN;
3847 	struct net *net = dev_net(dev);
3848 	struct inet6_dev *idev;
3849 	struct inet6_ifaddr *ifa;
3850 	LIST_HEAD(tmp_addr_list);
3851 	bool keep_addr = false;
3852 	bool was_ready;
3853 	int state, i;
3854 
3855 	ASSERT_RTNL();
3856 
3857 	rt6_disable_ip(dev, event);
3858 
3859 	idev = __in6_dev_get(dev);
3860 	if (!idev)
3861 		return -ENODEV;
3862 
3863 	/*
3864 	 * Step 1: remove reference to ipv6 device from parent device.
3865 	 *	   Do not dev_put!
3866 	 */
3867 	if (unregister) {
3868 		idev->dead = 1;
3869 
3870 		/* protected by rtnl_lock */
3871 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3872 
3873 		/* Step 1.5: remove snmp6 entry */
3874 		snmp6_unregister_dev(idev);
3875 
3876 	}
3877 
3878 	/* combine the user config with event to determine if permanent
3879 	 * addresses are to be removed from address hash table
3880 	 */
3881 	if (!unregister && !idev->cnf.disable_ipv6) {
3882 		/* aggregate the system setting and interface setting */
3883 		int _keep_addr = READ_ONCE(net->ipv6.devconf_all->keep_addr_on_down);
3884 
3885 		if (!_keep_addr)
3886 			_keep_addr = READ_ONCE(idev->cnf.keep_addr_on_down);
3887 
3888 		keep_addr = (_keep_addr > 0);
3889 	}
3890 
3891 	/* Step 2: clear hash table */
3892 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3893 		struct hlist_head *h = &net->ipv6.inet6_addr_lst[i];
3894 
3895 		spin_lock_bh(&net->ipv6.addrconf_hash_lock);
3896 restart:
3897 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3898 			if (ifa->idev == idev) {
3899 				addrconf_del_dad_work(ifa);
3900 				/* combined flag + permanent flag decide if
3901 				 * address is retained on a down event
3902 				 */
3903 				if (!keep_addr ||
3904 				    !(ifa->flags & IFA_F_PERMANENT) ||
3905 				    addr_is_local(&ifa->addr)) {
3906 					hlist_del_init_rcu(&ifa->addr_lst);
3907 					goto restart;
3908 				}
3909 			}
3910 		}
3911 		spin_unlock_bh(&net->ipv6.addrconf_hash_lock);
3912 	}
3913 
3914 	write_lock_bh(&idev->lock);
3915 
3916 	addrconf_del_rs_timer(idev);
3917 
3918 	/* Step 2: clear flags for stateless addrconf, repeated down
3919 	 *         detection
3920 	 */
3921 	was_ready = idev->if_flags & IF_READY;
3922 	if (!unregister)
3923 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3924 
3925 	/* Step 3: clear tempaddr list */
3926 	while (!list_empty(&idev->tempaddr_list)) {
3927 		ifa = list_first_entry(&idev->tempaddr_list,
3928 				       struct inet6_ifaddr, tmp_list);
3929 		list_del(&ifa->tmp_list);
3930 		write_unlock_bh(&idev->lock);
3931 		spin_lock_bh(&ifa->lock);
3932 
3933 		if (ifa->ifpub) {
3934 			in6_ifa_put(ifa->ifpub);
3935 			ifa->ifpub = NULL;
3936 		}
3937 		spin_unlock_bh(&ifa->lock);
3938 		in6_ifa_put(ifa);
3939 		write_lock_bh(&idev->lock);
3940 	}
3941 
3942 	list_for_each_entry(ifa, &idev->addr_list, if_list)
3943 		list_add_tail(&ifa->if_list_aux, &tmp_addr_list);
3944 	write_unlock_bh(&idev->lock);
3945 
3946 	while (!list_empty(&tmp_addr_list)) {
3947 		struct fib6_info *rt = NULL;
3948 		bool keep;
3949 
3950 		ifa = list_first_entry(&tmp_addr_list,
3951 				       struct inet6_ifaddr, if_list_aux);
3952 		list_del(&ifa->if_list_aux);
3953 
3954 		addrconf_del_dad_work(ifa);
3955 
3956 		keep = keep_addr && (ifa->flags & IFA_F_PERMANENT) &&
3957 			!addr_is_local(&ifa->addr);
3958 
3959 		spin_lock_bh(&ifa->lock);
3960 
3961 		if (keep) {
3962 			/* set state to skip the notifier below */
3963 			state = INET6_IFADDR_STATE_DEAD;
3964 			ifa->state = INET6_IFADDR_STATE_PREDAD;
3965 			if (!(ifa->flags & IFA_F_NODAD))
3966 				ifa->flags |= IFA_F_TENTATIVE;
3967 
3968 			rt = ifa->rt;
3969 			ifa->rt = NULL;
3970 		} else {
3971 			state = ifa->state;
3972 			ifa->state = INET6_IFADDR_STATE_DEAD;
3973 		}
3974 
3975 		spin_unlock_bh(&ifa->lock);
3976 
3977 		if (rt)
3978 			ip6_del_rt(net, rt, false);
3979 
3980 		if (state != INET6_IFADDR_STATE_DEAD) {
3981 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3982 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3983 		} else {
3984 			if (idev->cnf.forwarding)
3985 				addrconf_leave_anycast(ifa);
3986 			addrconf_leave_solict(ifa->idev, &ifa->addr);
3987 		}
3988 
3989 		if (!keep) {
3990 			write_lock_bh(&idev->lock);
3991 			list_del_rcu(&ifa->if_list);
3992 			write_unlock_bh(&idev->lock);
3993 			in6_ifa_put(ifa);
3994 		}
3995 	}
3996 
3997 	/* Step 5: Discard anycast and multicast list */
3998 	if (unregister) {
3999 		ipv6_ac_destroy_dev(idev);
4000 		ipv6_mc_destroy_dev(idev);
4001 	} else if (was_ready) {
4002 		ipv6_mc_down(idev);
4003 	}
4004 
4005 	WRITE_ONCE(idev->tstamp, jiffies);
4006 	idev->ra_mtu = 0;
4007 
4008 	/* Last: Shot the device (if unregistered) */
4009 	if (unregister) {
4010 		addrconf_sysctl_unregister(idev);
4011 		neigh_parms_release(&nd_tbl, idev->nd_parms);
4012 		neigh_ifdown(&nd_tbl, dev);
4013 		in6_dev_put(idev);
4014 	}
4015 	return 0;
4016 }
4017 
addrconf_rs_timer(struct timer_list * t)4018 static void addrconf_rs_timer(struct timer_list *t)
4019 {
4020 	struct inet6_dev *idev = timer_container_of(idev, t, rs_timer);
4021 	struct net_device *dev = idev->dev;
4022 	struct in6_addr lladdr;
4023 	int rtr_solicits;
4024 
4025 	write_lock(&idev->lock);
4026 	if (idev->dead || !(idev->if_flags & IF_READY))
4027 		goto out;
4028 
4029 	if (!ipv6_accept_ra(idev))
4030 		goto out;
4031 
4032 	/* Announcement received after solicitation was sent */
4033 	if (idev->if_flags & IF_RA_RCVD)
4034 		goto out;
4035 
4036 	rtr_solicits = READ_ONCE(idev->cnf.rtr_solicits);
4037 
4038 	if (idev->rs_probes++ < rtr_solicits || rtr_solicits < 0) {
4039 		write_unlock(&idev->lock);
4040 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4041 			ndisc_send_rs(dev, &lladdr,
4042 				      &in6addr_linklocal_allrouters);
4043 		else
4044 			goto put;
4045 
4046 		write_lock(&idev->lock);
4047 		idev->rs_interval = rfc3315_s14_backoff_update(
4048 				idev->rs_interval,
4049 				READ_ONCE(idev->cnf.rtr_solicit_max_interval));
4050 		/* The wait after the last probe can be shorter */
4051 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
4052 					     READ_ONCE(idev->cnf.rtr_solicits)) ?
4053 				      READ_ONCE(idev->cnf.rtr_solicit_delay) :
4054 				      idev->rs_interval);
4055 	} else {
4056 		/*
4057 		 * Note: we do not support deprecated "all on-link"
4058 		 * assumption any longer.
4059 		 */
4060 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
4061 	}
4062 
4063 out:
4064 	write_unlock(&idev->lock);
4065 put:
4066 	in6_dev_put(idev);
4067 }
4068 
4069 /*
4070  *	Duplicate Address Detection
4071  */
addrconf_dad_kick(struct inet6_ifaddr * ifp)4072 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
4073 {
4074 	struct inet6_dev *idev = ifp->idev;
4075 	unsigned long rand_num;
4076 	u64 nonce;
4077 
4078 	if (ifp->flags & IFA_F_OPTIMISTIC)
4079 		rand_num = 0;
4080 	else
4081 		rand_num = get_random_u32_below(
4082 				READ_ONCE(idev->cnf.rtr_solicit_delay) ? : 1);
4083 
4084 	nonce = 0;
4085 	if (READ_ONCE(idev->cnf.enhanced_dad) ||
4086 	    READ_ONCE(dev_net(idev->dev)->ipv6.devconf_all->enhanced_dad)) {
4087 		do
4088 			get_random_bytes(&nonce, 6);
4089 		while (nonce == 0);
4090 	}
4091 	ifp->dad_nonce = nonce;
4092 	ifp->dad_probes = READ_ONCE(idev->cnf.dad_transmits);
4093 	addrconf_mod_dad_work(ifp, rand_num);
4094 }
4095 
addrconf_dad_begin(struct inet6_ifaddr * ifp)4096 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
4097 {
4098 	struct inet6_dev *idev = ifp->idev;
4099 	struct net_device *dev = idev->dev;
4100 	bool bump_id, notify = false;
4101 	struct net *net;
4102 
4103 	addrconf_join_solict(dev, &ifp->addr);
4104 
4105 	read_lock_bh(&idev->lock);
4106 	spin_lock(&ifp->lock);
4107 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
4108 		goto out;
4109 
4110 	net = dev_net(dev);
4111 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
4112 	    (READ_ONCE(net->ipv6.devconf_all->accept_dad) < 1 &&
4113 	     READ_ONCE(idev->cnf.accept_dad) < 1) ||
4114 	    !(ifp->flags&IFA_F_TENTATIVE) ||
4115 	    ifp->flags & IFA_F_NODAD) {
4116 		bool send_na = false;
4117 
4118 		if (ifp->flags & IFA_F_TENTATIVE &&
4119 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4120 			send_na = true;
4121 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4122 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4123 		spin_unlock(&ifp->lock);
4124 		read_unlock_bh(&idev->lock);
4125 
4126 		addrconf_dad_completed(ifp, bump_id, send_na);
4127 		return;
4128 	}
4129 
4130 	if (!(idev->if_flags & IF_READY)) {
4131 		spin_unlock(&ifp->lock);
4132 		read_unlock_bh(&idev->lock);
4133 		/*
4134 		 * If the device is not ready:
4135 		 * - keep it tentative if it is a permanent address.
4136 		 * - otherwise, kill it.
4137 		 */
4138 		in6_ifa_hold(ifp);
4139 		addrconf_dad_stop(ifp, 0);
4140 		return;
4141 	}
4142 
4143 	/*
4144 	 * Optimistic nodes can start receiving
4145 	 * Frames right away
4146 	 */
4147 	if (ifp->flags & IFA_F_OPTIMISTIC) {
4148 		ip6_ins_rt(net, ifp->rt);
4149 		if (ipv6_use_optimistic_addr(net, idev)) {
4150 			/* Because optimistic nodes can use this address,
4151 			 * notify listeners. If DAD fails, RTM_DELADDR is sent.
4152 			 */
4153 			notify = true;
4154 		}
4155 	}
4156 
4157 	addrconf_dad_kick(ifp);
4158 out:
4159 	spin_unlock(&ifp->lock);
4160 	read_unlock_bh(&idev->lock);
4161 	if (notify)
4162 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
4163 }
4164 
addrconf_dad_start(struct inet6_ifaddr * ifp)4165 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
4166 {
4167 	bool begin_dad = false;
4168 
4169 	spin_lock_bh(&ifp->lock);
4170 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
4171 		ifp->state = INET6_IFADDR_STATE_PREDAD;
4172 		begin_dad = true;
4173 	}
4174 	spin_unlock_bh(&ifp->lock);
4175 
4176 	if (begin_dad)
4177 		addrconf_mod_dad_work(ifp, 0);
4178 }
4179 
addrconf_dad_work(struct work_struct * w)4180 static void addrconf_dad_work(struct work_struct *w)
4181 {
4182 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
4183 						struct inet6_ifaddr,
4184 						dad_work);
4185 	struct inet6_dev *idev = ifp->idev;
4186 	bool bump_id, disable_ipv6 = false;
4187 	struct in6_addr mcaddr;
4188 	struct net *net;
4189 
4190 	enum {
4191 		DAD_PROCESS,
4192 		DAD_BEGIN,
4193 		DAD_ABORT,
4194 	} action = DAD_PROCESS;
4195 
4196 	net = dev_net(idev->dev);
4197 
4198 	rtnl_net_lock(net);
4199 
4200 	spin_lock_bh(&ifp->lock);
4201 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
4202 		action = DAD_BEGIN;
4203 		ifp->state = INET6_IFADDR_STATE_DAD;
4204 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
4205 		action = DAD_ABORT;
4206 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
4207 
4208 		if ((READ_ONCE(net->ipv6.devconf_all->accept_dad) > 1 ||
4209 		     READ_ONCE(idev->cnf.accept_dad) > 1) &&
4210 		    !idev->cnf.disable_ipv6 &&
4211 		    !(ifp->flags & IFA_F_STABLE_PRIVACY)) {
4212 			struct in6_addr addr;
4213 
4214 			addr.s6_addr32[0] = htonl(0xfe800000);
4215 			addr.s6_addr32[1] = 0;
4216 
4217 			if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
4218 			    ipv6_addr_equal(&ifp->addr, &addr)) {
4219 				/* DAD failed for link-local based on MAC */
4220 				WRITE_ONCE(idev->cnf.disable_ipv6, 1);
4221 
4222 				pr_info("%s: IPv6 being disabled!\n",
4223 					ifp->idev->dev->name);
4224 				disable_ipv6 = true;
4225 			}
4226 		}
4227 	}
4228 	spin_unlock_bh(&ifp->lock);
4229 
4230 	if (action == DAD_BEGIN) {
4231 		addrconf_dad_begin(ifp);
4232 		goto out;
4233 	} else if (action == DAD_ABORT) {
4234 		in6_ifa_hold(ifp);
4235 		addrconf_dad_stop(ifp, 1);
4236 		if (disable_ipv6)
4237 			addrconf_ifdown(idev->dev, false);
4238 		goto out;
4239 	}
4240 
4241 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
4242 		goto out;
4243 
4244 	write_lock_bh(&idev->lock);
4245 	if (idev->dead || !(idev->if_flags & IF_READY)) {
4246 		write_unlock_bh(&idev->lock);
4247 		goto out;
4248 	}
4249 
4250 	spin_lock(&ifp->lock);
4251 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
4252 		spin_unlock(&ifp->lock);
4253 		write_unlock_bh(&idev->lock);
4254 		goto out;
4255 	}
4256 
4257 	if (ifp->dad_probes == 0) {
4258 		bool send_na = false;
4259 
4260 		/*
4261 		 * DAD was successful
4262 		 */
4263 
4264 		if (ifp->flags & IFA_F_TENTATIVE &&
4265 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4266 			send_na = true;
4267 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4268 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4269 		spin_unlock(&ifp->lock);
4270 		write_unlock_bh(&idev->lock);
4271 
4272 		addrconf_dad_completed(ifp, bump_id, send_na);
4273 
4274 		goto out;
4275 	}
4276 
4277 	ifp->dad_probes--;
4278 	addrconf_mod_dad_work(ifp,
4279 			      max(NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME),
4280 				  HZ/100));
4281 	spin_unlock(&ifp->lock);
4282 	write_unlock_bh(&idev->lock);
4283 
4284 	/* send a neighbour solicitation for our addr */
4285 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
4286 	ndisc_send_ns(ifp->idev->dev, &ifp->addr, &mcaddr, &in6addr_any,
4287 		      ifp->dad_nonce);
4288 out:
4289 	in6_ifa_put(ifp);
4290 	rtnl_net_unlock(net);
4291 }
4292 
4293 /* ifp->idev must be at least read locked */
ipv6_lonely_lladdr(struct inet6_ifaddr * ifp)4294 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
4295 {
4296 	struct inet6_ifaddr *ifpiter;
4297 	struct inet6_dev *idev = ifp->idev;
4298 
4299 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
4300 		if (ifpiter->scope > IFA_LINK)
4301 			break;
4302 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
4303 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
4304 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
4305 		    IFA_F_PERMANENT)
4306 			return false;
4307 	}
4308 	return true;
4309 }
4310 
addrconf_dad_completed(struct inet6_ifaddr * ifp,bool bump_id,bool send_na)4311 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
4312 				   bool send_na)
4313 {
4314 	struct net_device *dev = ifp->idev->dev;
4315 	struct in6_addr lladdr;
4316 	bool send_rs, send_mld;
4317 
4318 	addrconf_del_dad_work(ifp);
4319 
4320 	/*
4321 	 *	Configure the address for reception. Now it is valid.
4322 	 */
4323 
4324 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
4325 
4326 	/* If added prefix is link local and we are prepared to process
4327 	   router advertisements, start sending router solicitations.
4328 	 */
4329 
4330 	read_lock_bh(&ifp->idev->lock);
4331 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
4332 	send_rs = send_mld &&
4333 		  ipv6_accept_ra(ifp->idev) &&
4334 		  READ_ONCE(ifp->idev->cnf.rtr_solicits) != 0 &&
4335 		  (dev->flags & IFF_LOOPBACK) == 0 &&
4336 		  (dev->type != ARPHRD_TUNNEL) &&
4337 		  !netif_is_team_port(dev);
4338 	read_unlock_bh(&ifp->idev->lock);
4339 
4340 	/* While dad is in progress mld report's source address is in6_addrany.
4341 	 * Resend with proper ll now.
4342 	 */
4343 	if (send_mld)
4344 		ipv6_mc_dad_complete(ifp->idev);
4345 
4346 	/* send unsolicited NA if enabled */
4347 	if (send_na &&
4348 	    (READ_ONCE(ifp->idev->cnf.ndisc_notify) ||
4349 	     READ_ONCE(dev_net(dev)->ipv6.devconf_all->ndisc_notify))) {
4350 		ndisc_send_na(dev, &in6addr_linklocal_allnodes, &ifp->addr,
4351 			      /*router=*/ !!ifp->idev->cnf.forwarding,
4352 			      /*solicited=*/ false, /*override=*/ true,
4353 			      /*inc_opt=*/ true);
4354 	}
4355 
4356 	if (send_rs) {
4357 		/*
4358 		 *	If a host as already performed a random delay
4359 		 *	[...] as part of DAD [...] there is no need
4360 		 *	to delay again before sending the first RS
4361 		 */
4362 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4363 			return;
4364 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
4365 
4366 		write_lock_bh(&ifp->idev->lock);
4367 		spin_lock(&ifp->lock);
4368 		ifp->idev->rs_interval = rfc3315_s14_backoff_init(
4369 			READ_ONCE(ifp->idev->cnf.rtr_solicit_interval));
4370 		ifp->idev->rs_probes = 1;
4371 		ifp->idev->if_flags |= IF_RS_SENT;
4372 		addrconf_mod_rs_timer(ifp->idev, ifp->idev->rs_interval);
4373 		spin_unlock(&ifp->lock);
4374 		write_unlock_bh(&ifp->idev->lock);
4375 	}
4376 
4377 	if (bump_id)
4378 		rt_genid_bump_ipv6(dev_net(dev));
4379 
4380 	/* Make sure that a new temporary address will be created
4381 	 * before this temporary address becomes deprecated.
4382 	 */
4383 	if (ifp->flags & IFA_F_TEMPORARY)
4384 		addrconf_verify_rtnl(dev_net(dev));
4385 }
4386 
addrconf_dad_run(struct inet6_dev * idev,bool restart)4387 static void addrconf_dad_run(struct inet6_dev *idev, bool restart)
4388 {
4389 	struct inet6_ifaddr *ifp;
4390 
4391 	read_lock_bh(&idev->lock);
4392 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4393 		spin_lock(&ifp->lock);
4394 		if ((ifp->flags & IFA_F_TENTATIVE &&
4395 		     ifp->state == INET6_IFADDR_STATE_DAD) || restart) {
4396 			if (restart)
4397 				ifp->state = INET6_IFADDR_STATE_PREDAD;
4398 			addrconf_dad_kick(ifp);
4399 		}
4400 		spin_unlock(&ifp->lock);
4401 	}
4402 	read_unlock_bh(&idev->lock);
4403 }
4404 
4405 #ifdef CONFIG_PROC_FS
4406 struct if6_iter_state {
4407 	struct seq_net_private p;
4408 	int bucket;
4409 	int offset;
4410 };
4411 
if6_get_first(struct seq_file * seq,loff_t pos)4412 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
4413 {
4414 	struct if6_iter_state *state = seq->private;
4415 	struct net *net = seq_file_net(seq);
4416 	struct inet6_ifaddr *ifa = NULL;
4417 	int p = 0;
4418 
4419 	/* initial bucket if pos is 0 */
4420 	if (pos == 0) {
4421 		state->bucket = 0;
4422 		state->offset = 0;
4423 	}
4424 
4425 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
4426 		hlist_for_each_entry_rcu(ifa, &net->ipv6.inet6_addr_lst[state->bucket],
4427 					 addr_lst) {
4428 			/* sync with offset */
4429 			if (p < state->offset) {
4430 				p++;
4431 				continue;
4432 			}
4433 			return ifa;
4434 		}
4435 
4436 		/* prepare for next bucket */
4437 		state->offset = 0;
4438 		p = 0;
4439 	}
4440 	return NULL;
4441 }
4442 
if6_get_next(struct seq_file * seq,struct inet6_ifaddr * ifa)4443 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
4444 					 struct inet6_ifaddr *ifa)
4445 {
4446 	struct if6_iter_state *state = seq->private;
4447 	struct net *net = seq_file_net(seq);
4448 
4449 	hlist_for_each_entry_continue_rcu(ifa, addr_lst) {
4450 		state->offset++;
4451 		return ifa;
4452 	}
4453 
4454 	state->offset = 0;
4455 	while (++state->bucket < IN6_ADDR_HSIZE) {
4456 		hlist_for_each_entry_rcu(ifa,
4457 				     &net->ipv6.inet6_addr_lst[state->bucket], addr_lst) {
4458 			return ifa;
4459 		}
4460 	}
4461 
4462 	return NULL;
4463 }
4464 
if6_seq_start(struct seq_file * seq,loff_t * pos)4465 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
4466 	__acquires(rcu)
4467 {
4468 	rcu_read_lock();
4469 	return if6_get_first(seq, *pos);
4470 }
4471 
if6_seq_next(struct seq_file * seq,void * v,loff_t * pos)4472 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4473 {
4474 	struct inet6_ifaddr *ifa;
4475 
4476 	ifa = if6_get_next(seq, v);
4477 	++*pos;
4478 	return ifa;
4479 }
4480 
if6_seq_stop(struct seq_file * seq,void * v)4481 static void if6_seq_stop(struct seq_file *seq, void *v)
4482 	__releases(rcu)
4483 {
4484 	rcu_read_unlock();
4485 }
4486 
if6_seq_show(struct seq_file * seq,void * v)4487 static int if6_seq_show(struct seq_file *seq, void *v)
4488 {
4489 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
4490 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
4491 		   &ifp->addr,
4492 		   ifp->idev->dev->ifindex,
4493 		   ifp->prefix_len,
4494 		   ifp->scope,
4495 		   (u8) ifp->flags,
4496 		   ifp->idev->dev->name);
4497 	return 0;
4498 }
4499 
4500 static const struct seq_operations if6_seq_ops = {
4501 	.start	= if6_seq_start,
4502 	.next	= if6_seq_next,
4503 	.show	= if6_seq_show,
4504 	.stop	= if6_seq_stop,
4505 };
4506 
if6_proc_net_init(struct net * net)4507 static int __net_init if6_proc_net_init(struct net *net)
4508 {
4509 	if (!proc_create_net("if_inet6", 0444, net->proc_net, &if6_seq_ops,
4510 			sizeof(struct if6_iter_state)))
4511 		return -ENOMEM;
4512 	return 0;
4513 }
4514 
if6_proc_net_exit(struct net * net)4515 static void __net_exit if6_proc_net_exit(struct net *net)
4516 {
4517 	remove_proc_entry("if_inet6", net->proc_net);
4518 }
4519 
4520 static struct pernet_operations if6_proc_net_ops = {
4521 	.init = if6_proc_net_init,
4522 	.exit = if6_proc_net_exit,
4523 };
4524 
if6_proc_init(void)4525 int __init if6_proc_init(void)
4526 {
4527 	return register_pernet_subsys(&if6_proc_net_ops);
4528 }
4529 
if6_proc_exit(void)4530 void if6_proc_exit(void)
4531 {
4532 	unregister_pernet_subsys(&if6_proc_net_ops);
4533 }
4534 #endif	/* CONFIG_PROC_FS */
4535 
4536 #if IS_ENABLED(CONFIG_IPV6_MIP6)
4537 /* Check if address is a home address configured on any interface. */
ipv6_chk_home_addr(struct net * net,const struct in6_addr * addr)4538 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
4539 {
4540 	unsigned int hash = inet6_addr_hash(net, addr);
4541 	struct inet6_ifaddr *ifp = NULL;
4542 	int ret = 0;
4543 
4544 	rcu_read_lock();
4545 	hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
4546 		if (ipv6_addr_equal(&ifp->addr, addr) &&
4547 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
4548 			ret = 1;
4549 			break;
4550 		}
4551 	}
4552 	rcu_read_unlock();
4553 	return ret;
4554 }
4555 #endif
4556 
4557 /* RFC6554 has some algorithm to avoid loops in segment routing by
4558  * checking if the segments contains any of a local interface address.
4559  *
4560  * Quote:
4561  *
4562  * To detect loops in the SRH, a router MUST determine if the SRH
4563  * includes multiple addresses assigned to any interface on that router.
4564  * If such addresses appear more than once and are separated by at least
4565  * one address not assigned to that router.
4566  */
ipv6_chk_rpl_srh_loop(struct net * net,const struct in6_addr * segs,unsigned char nsegs)4567 int ipv6_chk_rpl_srh_loop(struct net *net, const struct in6_addr *segs,
4568 			  unsigned char nsegs)
4569 {
4570 	const struct in6_addr *addr;
4571 	int i, ret = 0, found = 0;
4572 	struct inet6_ifaddr *ifp;
4573 	bool separated = false;
4574 	unsigned int hash;
4575 	bool hash_found;
4576 
4577 	rcu_read_lock();
4578 	for (i = 0; i < nsegs; i++) {
4579 		addr = &segs[i];
4580 		hash = inet6_addr_hash(net, addr);
4581 
4582 		hash_found = false;
4583 		hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
4584 
4585 			if (ipv6_addr_equal(&ifp->addr, addr)) {
4586 				hash_found = true;
4587 				break;
4588 			}
4589 		}
4590 
4591 		if (hash_found) {
4592 			if (found > 1 && separated) {
4593 				ret = 1;
4594 				break;
4595 			}
4596 
4597 			separated = false;
4598 			found++;
4599 		} else {
4600 			separated = true;
4601 		}
4602 	}
4603 	rcu_read_unlock();
4604 
4605 	return ret;
4606 }
4607 
4608 /*
4609  *	Periodic address status verification
4610  */
4611 
addrconf_verify_rtnl(struct net * net)4612 static void addrconf_verify_rtnl(struct net *net)
4613 {
4614 	unsigned long now, next, next_sec, next_sched;
4615 	struct inet6_ifaddr *ifp;
4616 	int i;
4617 
4618 	ASSERT_RTNL();
4619 
4620 	rcu_read_lock_bh();
4621 	now = jiffies;
4622 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
4623 
4624 	cancel_delayed_work(&net->ipv6.addr_chk_work);
4625 
4626 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
4627 restart:
4628 		hlist_for_each_entry_rcu_bh(ifp, &net->ipv6.inet6_addr_lst[i], addr_lst) {
4629 			unsigned long age;
4630 
4631 			/* When setting preferred_lft to a value not zero or
4632 			 * infinity, while valid_lft is infinity
4633 			 * IFA_F_PERMANENT has a non-infinity life time.
4634 			 */
4635 			if ((ifp->flags & IFA_F_PERMANENT) &&
4636 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
4637 				continue;
4638 
4639 			spin_lock(&ifp->lock);
4640 			/* We try to batch several events at once. */
4641 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
4642 
4643 			if ((ifp->flags&IFA_F_TEMPORARY) &&
4644 			    !(ifp->flags&IFA_F_TENTATIVE) &&
4645 			    ifp->prefered_lft != INFINITY_LIFE_TIME &&
4646 			    !ifp->regen_count && ifp->ifpub) {
4647 				/* This is a non-regenerated temporary addr. */
4648 
4649 				unsigned long regen_advance = ipv6_get_regen_advance(ifp->idev);
4650 
4651 				if (age + regen_advance >= ifp->prefered_lft) {
4652 					struct inet6_ifaddr *ifpub = ifp->ifpub;
4653 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4654 						next = ifp->tstamp + ifp->prefered_lft * HZ;
4655 
4656 					ifp->regen_count++;
4657 					in6_ifa_hold(ifp);
4658 					in6_ifa_hold(ifpub);
4659 					spin_unlock(&ifp->lock);
4660 
4661 					spin_lock(&ifpub->lock);
4662 					ifpub->regen_count = 0;
4663 					spin_unlock(&ifpub->lock);
4664 					rcu_read_unlock_bh();
4665 					ipv6_create_tempaddr(ifpub, true);
4666 					in6_ifa_put(ifpub);
4667 					in6_ifa_put(ifp);
4668 					rcu_read_lock_bh();
4669 					goto restart;
4670 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
4671 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
4672 			}
4673 
4674 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
4675 			    age >= ifp->valid_lft) {
4676 				spin_unlock(&ifp->lock);
4677 				in6_ifa_hold(ifp);
4678 				rcu_read_unlock_bh();
4679 				ipv6_del_addr(ifp);
4680 				rcu_read_lock_bh();
4681 				goto restart;
4682 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
4683 				spin_unlock(&ifp->lock);
4684 				continue;
4685 			} else if (age >= ifp->prefered_lft) {
4686 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
4687 				int deprecate = 0;
4688 
4689 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
4690 					deprecate = 1;
4691 					ifp->flags |= IFA_F_DEPRECATED;
4692 				}
4693 
4694 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
4695 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
4696 					next = ifp->tstamp + ifp->valid_lft * HZ;
4697 
4698 				spin_unlock(&ifp->lock);
4699 
4700 				if (deprecate) {
4701 					in6_ifa_hold(ifp);
4702 
4703 					ipv6_ifa_notify(0, ifp);
4704 					in6_ifa_put(ifp);
4705 					goto restart;
4706 				}
4707 			} else {
4708 				/* ifp->prefered_lft <= ifp->valid_lft */
4709 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4710 					next = ifp->tstamp + ifp->prefered_lft * HZ;
4711 				spin_unlock(&ifp->lock);
4712 			}
4713 		}
4714 	}
4715 
4716 	next_sec = round_jiffies_up(next);
4717 	next_sched = next;
4718 
4719 	/* If rounded timeout is accurate enough, accept it. */
4720 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
4721 		next_sched = next_sec;
4722 
4723 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
4724 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
4725 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
4726 
4727 	pr_debug("now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
4728 		 now, next, next_sec, next_sched);
4729 	mod_delayed_work(addrconf_wq, &net->ipv6.addr_chk_work, next_sched - now);
4730 	rcu_read_unlock_bh();
4731 }
4732 
addrconf_verify_work(struct work_struct * w)4733 static void addrconf_verify_work(struct work_struct *w)
4734 {
4735 	struct net *net = container_of(to_delayed_work(w), struct net,
4736 				       ipv6.addr_chk_work);
4737 
4738 	rtnl_net_lock(net);
4739 	addrconf_verify_rtnl(net);
4740 	rtnl_net_unlock(net);
4741 }
4742 
addrconf_verify(struct net * net)4743 static void addrconf_verify(struct net *net)
4744 {
4745 	mod_delayed_work(addrconf_wq, &net->ipv6.addr_chk_work, 0);
4746 }
4747 
extract_addr(struct nlattr * addr,struct nlattr * local,struct in6_addr ** peer_pfx)4748 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
4749 				     struct in6_addr **peer_pfx)
4750 {
4751 	struct in6_addr *pfx = NULL;
4752 
4753 	*peer_pfx = NULL;
4754 
4755 	if (addr)
4756 		pfx = nla_data(addr);
4757 
4758 	if (local) {
4759 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
4760 			*peer_pfx = pfx;
4761 		pfx = nla_data(local);
4762 	}
4763 
4764 	return pfx;
4765 }
4766 
4767 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
4768 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
4769 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
4770 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
4771 	[IFA_FLAGS]		= { .len = sizeof(u32) },
4772 	[IFA_RT_PRIORITY]	= { .len = sizeof(u32) },
4773 	[IFA_TARGET_NETNSID]	= { .type = NLA_S32 },
4774 	[IFA_PROTO]		= { .type = NLA_U8 },
4775 };
4776 
4777 static int
inet6_rtm_deladdr(struct sk_buff * skb,struct nlmsghdr * nlh,struct netlink_ext_ack * extack)4778 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
4779 		  struct netlink_ext_ack *extack)
4780 {
4781 	struct net *net = sock_net(skb->sk);
4782 	struct ifaddrmsg *ifm;
4783 	struct nlattr *tb[IFA_MAX+1];
4784 	struct in6_addr *pfx, *peer_pfx;
4785 	u32 ifa_flags;
4786 	int err;
4787 
4788 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4789 				     ifa_ipv6_policy, extack);
4790 	if (err < 0)
4791 		return err;
4792 
4793 	ifm = nlmsg_data(nlh);
4794 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4795 	if (!pfx)
4796 		return -EINVAL;
4797 
4798 	ifa_flags = nla_get_u32_default(tb[IFA_FLAGS], ifm->ifa_flags);
4799 
4800 	/* We ignore other flags so far. */
4801 	ifa_flags &= IFA_F_MANAGETEMPADDR;
4802 
4803 	rtnl_net_lock(net);
4804 	err = inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
4805 			     ifm->ifa_prefixlen, extack);
4806 	rtnl_net_unlock(net);
4807 
4808 	return err;
4809 }
4810 
modify_prefix_route(struct net * net,struct inet6_ifaddr * ifp,unsigned long expires,u32 flags,bool modify_peer)4811 static int modify_prefix_route(struct net *net, struct inet6_ifaddr *ifp,
4812 			       unsigned long expires, u32 flags,
4813 			       bool modify_peer)
4814 {
4815 	struct fib6_table *table;
4816 	struct fib6_info *f6i;
4817 	u32 prio;
4818 
4819 	f6i = addrconf_get_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
4820 					ifp->prefix_len,
4821 					ifp->idev->dev, 0, RTF_DEFAULT, true);
4822 	if (!f6i)
4823 		return -ENOENT;
4824 
4825 	prio = ifp->rt_priority ? : IP6_RT_PRIO_ADDRCONF;
4826 	if (f6i->fib6_metric != prio) {
4827 		/* delete old one */
4828 		ip6_del_rt(dev_net(ifp->idev->dev), f6i, false);
4829 
4830 		/* add new one */
4831 		addrconf_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
4832 				      ifp->prefix_len,
4833 				      ifp->rt_priority, ifp->idev->dev,
4834 				      expires, flags, GFP_KERNEL);
4835 		return 0;
4836 	}
4837 	if (f6i != net->ipv6.fib6_null_entry) {
4838 		table = f6i->fib6_table;
4839 		spin_lock_bh(&table->tb6_lock);
4840 
4841 		if (!(flags & RTF_EXPIRES)) {
4842 			fib6_clean_expires(f6i);
4843 			fib6_remove_gc_list(f6i);
4844 		} else {
4845 			fib6_set_expires(f6i, expires);
4846 			fib6_add_gc_list(f6i);
4847 		}
4848 
4849 		spin_unlock_bh(&table->tb6_lock);
4850 	}
4851 	fib6_info_release(f6i);
4852 
4853 	return 0;
4854 }
4855 
inet6_addr_modify(struct net * net,struct inet6_ifaddr * ifp,struct ifa6_config * cfg,clock_t expires,u32 flags)4856 static int inet6_addr_modify(struct net *net, struct inet6_ifaddr *ifp,
4857 			     struct ifa6_config *cfg, clock_t expires,
4858 			     u32 flags)
4859 {
4860 	bool was_managetempaddr;
4861 	bool new_peer = false;
4862 	bool had_prefixroute;
4863 
4864 	ASSERT_RTNL_NET(net);
4865 
4866 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR &&
4867 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
4868 		return -EINVAL;
4869 
4870 	if (!(ifp->flags & IFA_F_TENTATIVE) || ifp->flags & IFA_F_DADFAILED)
4871 		cfg->ifa_flags &= ~IFA_F_OPTIMISTIC;
4872 
4873 	if (cfg->peer_pfx &&
4874 	    memcmp(&ifp->peer_addr, cfg->peer_pfx, sizeof(struct in6_addr))) {
4875 		if (!ipv6_addr_any(&ifp->peer_addr))
4876 			cleanup_prefix_route(ifp, expires, true, true);
4877 		new_peer = true;
4878 	}
4879 
4880 	spin_lock_bh(&ifp->lock);
4881 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
4882 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
4883 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
4884 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
4885 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4886 			IFA_F_NOPREFIXROUTE);
4887 	ifp->flags |= cfg->ifa_flags;
4888 	WRITE_ONCE(ifp->tstamp, jiffies);
4889 	WRITE_ONCE(ifp->valid_lft, cfg->valid_lft);
4890 	WRITE_ONCE(ifp->prefered_lft, cfg->preferred_lft);
4891 	WRITE_ONCE(ifp->ifa_proto, cfg->ifa_proto);
4892 
4893 	if (cfg->rt_priority && cfg->rt_priority != ifp->rt_priority)
4894 		WRITE_ONCE(ifp->rt_priority, cfg->rt_priority);
4895 
4896 	if (new_peer)
4897 		ifp->peer_addr = *cfg->peer_pfx;
4898 
4899 	spin_unlock_bh(&ifp->lock);
4900 	if (!(ifp->flags&IFA_F_TENTATIVE))
4901 		ipv6_ifa_notify(0, ifp);
4902 
4903 	if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
4904 		int rc = -ENOENT;
4905 
4906 		if (had_prefixroute)
4907 			rc = modify_prefix_route(net, ifp, expires, flags, false);
4908 
4909 		/* prefix route could have been deleted; if so restore it */
4910 		if (rc == -ENOENT) {
4911 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
4912 					      ifp->rt_priority, ifp->idev->dev,
4913 					      expires, flags, GFP_KERNEL);
4914 		}
4915 
4916 		if (had_prefixroute && !ipv6_addr_any(&ifp->peer_addr))
4917 			rc = modify_prefix_route(net, ifp, expires, flags, true);
4918 
4919 		if (rc == -ENOENT && !ipv6_addr_any(&ifp->peer_addr)) {
4920 			addrconf_prefix_route(&ifp->peer_addr, ifp->prefix_len,
4921 					      ifp->rt_priority, ifp->idev->dev,
4922 					      expires, flags, GFP_KERNEL);
4923 		}
4924 	} else if (had_prefixroute) {
4925 		enum cleanup_prefix_rt_t action;
4926 		unsigned long rt_expires;
4927 
4928 		write_lock_bh(&ifp->idev->lock);
4929 		action = check_cleanup_prefix_route(ifp, &rt_expires);
4930 		write_unlock_bh(&ifp->idev->lock);
4931 
4932 		if (action != CLEANUP_PREFIX_RT_NOP) {
4933 			cleanup_prefix_route(ifp, rt_expires,
4934 				action == CLEANUP_PREFIX_RT_DEL, false);
4935 		}
4936 	}
4937 
4938 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
4939 		if (was_managetempaddr && !(ifp->flags & IFA_F_MANAGETEMPADDR))
4940 			delete_tempaddrs(ifp->idev, ifp);
4941 		else
4942 			manage_tempaddrs(ifp->idev, ifp, cfg->valid_lft,
4943 					 cfg->preferred_lft, !was_managetempaddr,
4944 					 jiffies);
4945 	}
4946 
4947 	addrconf_verify_rtnl(net);
4948 
4949 	return 0;
4950 }
4951 
4952 static int
inet6_rtm_newaddr(struct sk_buff * skb,struct nlmsghdr * nlh,struct netlink_ext_ack * extack)4953 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
4954 		  struct netlink_ext_ack *extack)
4955 {
4956 	struct net *net = sock_net(skb->sk);
4957 	struct nlattr *tb[IFA_MAX+1];
4958 	struct in6_addr *peer_pfx;
4959 	struct inet6_ifaddr *ifa;
4960 	struct net_device *dev;
4961 	struct inet6_dev *idev;
4962 	struct ifa6_config cfg;
4963 	struct ifaddrmsg *ifm;
4964 	unsigned long timeout;
4965 	clock_t expires;
4966 	u32 flags;
4967 	int err;
4968 
4969 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4970 				     ifa_ipv6_policy, extack);
4971 	if (err < 0)
4972 		return err;
4973 
4974 	memset(&cfg, 0, sizeof(cfg));
4975 
4976 	ifm = nlmsg_data(nlh);
4977 	cfg.pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4978 	if (!cfg.pfx)
4979 		return -EINVAL;
4980 
4981 	cfg.peer_pfx = peer_pfx;
4982 	cfg.plen = ifm->ifa_prefixlen;
4983 	if (tb[IFA_RT_PRIORITY])
4984 		cfg.rt_priority = nla_get_u32(tb[IFA_RT_PRIORITY]);
4985 
4986 	if (tb[IFA_PROTO])
4987 		cfg.ifa_proto = nla_get_u8(tb[IFA_PROTO]);
4988 
4989 	cfg.ifa_flags = nla_get_u32_default(tb[IFA_FLAGS], ifm->ifa_flags);
4990 
4991 	/* We ignore other flags so far. */
4992 	cfg.ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS |
4993 			 IFA_F_MANAGETEMPADDR | IFA_F_NOPREFIXROUTE |
4994 			 IFA_F_MCAUTOJOIN | IFA_F_OPTIMISTIC;
4995 
4996 	cfg.ifa_flags |= IFA_F_PERMANENT;
4997 	cfg.valid_lft = INFINITY_LIFE_TIME;
4998 	cfg.preferred_lft = INFINITY_LIFE_TIME;
4999 	expires = 0;
5000 	flags = 0;
5001 
5002 	if (tb[IFA_CACHEINFO]) {
5003 		struct ifa_cacheinfo *ci;
5004 
5005 		ci = nla_data(tb[IFA_CACHEINFO]);
5006 		cfg.valid_lft = ci->ifa_valid;
5007 		cfg.preferred_lft = ci->ifa_prefered;
5008 
5009 		if (!cfg.valid_lft || cfg.preferred_lft > cfg.valid_lft) {
5010 			NL_SET_ERR_MSG_MOD(extack, "address lifetime invalid");
5011 			return -EINVAL;
5012 		}
5013 
5014 		timeout = addrconf_timeout_fixup(cfg.valid_lft, HZ);
5015 		if (addrconf_finite_timeout(timeout)) {
5016 			cfg.ifa_flags &= ~IFA_F_PERMANENT;
5017 			cfg.valid_lft = timeout;
5018 			expires = jiffies_to_clock_t(timeout * HZ);
5019 			flags = RTF_EXPIRES;
5020 		}
5021 
5022 		timeout = addrconf_timeout_fixup(cfg.preferred_lft, HZ);
5023 		if (addrconf_finite_timeout(timeout)) {
5024 			if (timeout == 0)
5025 				cfg.ifa_flags |= IFA_F_DEPRECATED;
5026 
5027 			cfg.preferred_lft = timeout;
5028 		}
5029 	}
5030 
5031 	rtnl_net_lock(net);
5032 
5033 	dev =  __dev_get_by_index(net, ifm->ifa_index);
5034 	if (!dev) {
5035 		NL_SET_ERR_MSG_MOD(extack, "Unable to find the interface");
5036 		err = -ENODEV;
5037 		goto unlock_rtnl;
5038 	}
5039 
5040 	netdev_lock_ops(dev);
5041 	idev = ipv6_find_idev(dev);
5042 	if (IS_ERR(idev)) {
5043 		err = PTR_ERR(idev);
5044 		goto unlock;
5045 	}
5046 
5047 	if (!ipv6_allow_optimistic_dad(net, idev))
5048 		cfg.ifa_flags &= ~IFA_F_OPTIMISTIC;
5049 
5050 	if (cfg.ifa_flags & IFA_F_NODAD &&
5051 	    cfg.ifa_flags & IFA_F_OPTIMISTIC) {
5052 		NL_SET_ERR_MSG(extack, "IFA_F_NODAD and IFA_F_OPTIMISTIC are mutually exclusive");
5053 		err = -EINVAL;
5054 		goto unlock;
5055 	}
5056 
5057 	ifa = ipv6_get_ifaddr(net, cfg.pfx, dev, 1);
5058 	if (!ifa) {
5059 		/*
5060 		 * It would be best to check for !NLM_F_CREATE here but
5061 		 * userspace already relies on not having to provide this.
5062 		 */
5063 		err = inet6_addr_add(net, dev, &cfg, expires, flags, extack);
5064 		goto unlock;
5065 	}
5066 
5067 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
5068 	    !(nlh->nlmsg_flags & NLM_F_REPLACE)) {
5069 		NL_SET_ERR_MSG_MOD(extack, "address already assigned");
5070 		err = -EEXIST;
5071 	} else {
5072 		err = inet6_addr_modify(net, ifa, &cfg, expires, flags);
5073 	}
5074 
5075 	in6_ifa_put(ifa);
5076 unlock:
5077 	netdev_unlock_ops(dev);
5078 unlock_rtnl:
5079 	rtnl_net_unlock(net);
5080 
5081 	return err;
5082 }
5083 
put_ifaddrmsg(struct nlmsghdr * nlh,u8 prefixlen,u32 flags,u8 scope,int ifindex)5084 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
5085 			  u8 scope, int ifindex)
5086 {
5087 	struct ifaddrmsg *ifm;
5088 
5089 	ifm = nlmsg_data(nlh);
5090 	ifm->ifa_family = AF_INET6;
5091 	ifm->ifa_prefixlen = prefixlen;
5092 	ifm->ifa_flags = flags;
5093 	ifm->ifa_scope = scope;
5094 	ifm->ifa_index = ifindex;
5095 }
5096 
put_cacheinfo(struct sk_buff * skb,unsigned long cstamp,unsigned long tstamp,u32 preferred,u32 valid)5097 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
5098 			 unsigned long tstamp, u32 preferred, u32 valid)
5099 {
5100 	struct ifa_cacheinfo ci;
5101 
5102 	ci.cstamp = cstamp_delta(cstamp);
5103 	ci.tstamp = cstamp_delta(tstamp);
5104 	ci.ifa_prefered = preferred;
5105 	ci.ifa_valid = valid;
5106 
5107 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
5108 }
5109 
rt_scope(int ifa_scope)5110 static inline int rt_scope(int ifa_scope)
5111 {
5112 	if (ifa_scope & IFA_HOST)
5113 		return RT_SCOPE_HOST;
5114 	else if (ifa_scope & IFA_LINK)
5115 		return RT_SCOPE_LINK;
5116 	else if (ifa_scope & IFA_SITE)
5117 		return RT_SCOPE_SITE;
5118 	else
5119 		return RT_SCOPE_UNIVERSE;
5120 }
5121 
inet6_ifaddr_msgsize(void)5122 static inline int inet6_ifaddr_msgsize(void)
5123 {
5124 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
5125 	       + nla_total_size(16) /* IFA_LOCAL */
5126 	       + nla_total_size(16) /* IFA_ADDRESS */
5127 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
5128 	       + nla_total_size(4)  /* IFA_FLAGS */
5129 	       + nla_total_size(1)  /* IFA_PROTO */
5130 	       + nla_total_size(4)  /* IFA_RT_PRIORITY */;
5131 }
5132 
inet6_fill_ifaddr(struct sk_buff * skb,const struct inet6_ifaddr * ifa,struct inet6_fill_args * args)5133 static int inet6_fill_ifaddr(struct sk_buff *skb,
5134 			     const struct inet6_ifaddr *ifa,
5135 			     struct inet6_fill_args *args)
5136 {
5137 	struct nlmsghdr *nlh;
5138 	u32 preferred, valid;
5139 	u32 flags, priority;
5140 	u8 proto;
5141 
5142 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5143 			sizeof(struct ifaddrmsg), args->flags);
5144 	if (!nlh)
5145 		return -EMSGSIZE;
5146 
5147 	flags = READ_ONCE(ifa->flags);
5148 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
5149 		      ifa->idev->dev->ifindex);
5150 
5151 	if (args->netnsid >= 0 &&
5152 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
5153 		goto error;
5154 
5155 	preferred = READ_ONCE(ifa->prefered_lft);
5156 	valid = READ_ONCE(ifa->valid_lft);
5157 
5158 	if (!((flags & IFA_F_PERMANENT) &&
5159 	      (preferred == INFINITY_LIFE_TIME))) {
5160 		if (preferred != INFINITY_LIFE_TIME) {
5161 			long tval = (jiffies - READ_ONCE(ifa->tstamp)) / HZ;
5162 
5163 			if (preferred > tval)
5164 				preferred -= tval;
5165 			else
5166 				preferred = 0;
5167 			if (valid != INFINITY_LIFE_TIME) {
5168 				if (valid > tval)
5169 					valid -= tval;
5170 				else
5171 					valid = 0;
5172 			}
5173 		}
5174 	} else {
5175 		preferred = INFINITY_LIFE_TIME;
5176 		valid = INFINITY_LIFE_TIME;
5177 	}
5178 
5179 	if (!ipv6_addr_any(&ifa->peer_addr)) {
5180 		if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||
5181 		    nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0)
5182 			goto error;
5183 	} else {
5184 		if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0)
5185 			goto error;
5186 	}
5187 
5188 	priority = READ_ONCE(ifa->rt_priority);
5189 	if (priority && nla_put_u32(skb, IFA_RT_PRIORITY, priority))
5190 		goto error;
5191 
5192 	if (put_cacheinfo(skb, ifa->cstamp, READ_ONCE(ifa->tstamp),
5193 			  preferred, valid) < 0)
5194 		goto error;
5195 
5196 	if (nla_put_u32(skb, IFA_FLAGS, flags) < 0)
5197 		goto error;
5198 
5199 	proto = READ_ONCE(ifa->ifa_proto);
5200 	if (proto && nla_put_u8(skb, IFA_PROTO, proto))
5201 		goto error;
5202 
5203 	nlmsg_end(skb, nlh);
5204 	return 0;
5205 
5206 error:
5207 	nlmsg_cancel(skb, nlh);
5208 	return -EMSGSIZE;
5209 }
5210 
inet6_fill_ifmcaddr(struct sk_buff * skb,const struct ifmcaddr6 * ifmca,struct inet6_fill_args * args)5211 int inet6_fill_ifmcaddr(struct sk_buff *skb,
5212 			const struct ifmcaddr6 *ifmca,
5213 			struct inet6_fill_args *args)
5214 {
5215 	int ifindex = ifmca->idev->dev->ifindex;
5216 	u8 scope = RT_SCOPE_UNIVERSE;
5217 	struct nlmsghdr *nlh;
5218 
5219 	if (!args->force_rt_scope_universe &&
5220 	    ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
5221 		scope = RT_SCOPE_SITE;
5222 
5223 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5224 			sizeof(struct ifaddrmsg), args->flags);
5225 	if (!nlh)
5226 		return -EMSGSIZE;
5227 
5228 	if (args->netnsid >= 0 &&
5229 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid)) {
5230 		nlmsg_cancel(skb, nlh);
5231 		return -EMSGSIZE;
5232 	}
5233 
5234 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
5235 	if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
5236 	    put_cacheinfo(skb, ifmca->mca_cstamp, READ_ONCE(ifmca->mca_tstamp),
5237 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
5238 		nlmsg_cancel(skb, nlh);
5239 		return -EMSGSIZE;
5240 	}
5241 
5242 	nlmsg_end(skb, nlh);
5243 	return 0;
5244 }
5245 
inet6_fill_ifacaddr(struct sk_buff * skb,const struct ifacaddr6 * ifaca,struct inet6_fill_args * args)5246 int inet6_fill_ifacaddr(struct sk_buff *skb,
5247 			const struct ifacaddr6 *ifaca,
5248 			struct inet6_fill_args *args)
5249 {
5250 	struct net_device *dev = fib6_info_nh_dev(ifaca->aca_rt);
5251 	int ifindex = dev ? dev->ifindex : 1;
5252 	u8 scope = RT_SCOPE_UNIVERSE;
5253 	struct nlmsghdr *nlh;
5254 
5255 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
5256 		scope = RT_SCOPE_SITE;
5257 
5258 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5259 			sizeof(struct ifaddrmsg), args->flags);
5260 	if (!nlh)
5261 		return -EMSGSIZE;
5262 
5263 	if (args->netnsid >= 0 &&
5264 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid)) {
5265 		nlmsg_cancel(skb, nlh);
5266 		return -EMSGSIZE;
5267 	}
5268 
5269 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
5270 	if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
5271 	    put_cacheinfo(skb, ifaca->aca_cstamp, READ_ONCE(ifaca->aca_tstamp),
5272 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
5273 		nlmsg_cancel(skb, nlh);
5274 		return -EMSGSIZE;
5275 	}
5276 
5277 	nlmsg_end(skb, nlh);
5278 	return 0;
5279 }
5280 
5281 /* called with rcu_read_lock() */
in6_dump_addrs(const struct inet6_dev * idev,struct sk_buff * skb,struct netlink_callback * cb,int * s_ip_idx,struct inet6_fill_args * fillargs)5282 static int in6_dump_addrs(const struct inet6_dev *idev, struct sk_buff *skb,
5283 			  struct netlink_callback *cb, int *s_ip_idx,
5284 			  struct inet6_fill_args *fillargs)
5285 {
5286 	const struct ifmcaddr6 *ifmca;
5287 	const struct ifacaddr6 *ifaca;
5288 	int ip_idx = 0;
5289 	int err = 0;
5290 
5291 	switch (fillargs->type) {
5292 	case UNICAST_ADDR: {
5293 		const struct inet6_ifaddr *ifa;
5294 		fillargs->event = RTM_NEWADDR;
5295 
5296 		/* unicast address incl. temp addr */
5297 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
5298 			if (ip_idx < *s_ip_idx)
5299 				goto next;
5300 			err = inet6_fill_ifaddr(skb, ifa, fillargs);
5301 			if (err < 0)
5302 				break;
5303 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
5304 next:
5305 			ip_idx++;
5306 		}
5307 		break;
5308 	}
5309 	case MULTICAST_ADDR:
5310 		fillargs->event = RTM_GETMULTICAST;
5311 
5312 		/* multicast address */
5313 		for (ifmca = rcu_dereference(idev->mc_list);
5314 		     ifmca;
5315 		     ifmca = rcu_dereference(ifmca->next), ip_idx++) {
5316 			if (ip_idx < *s_ip_idx)
5317 				continue;
5318 			err = inet6_fill_ifmcaddr(skb, ifmca, fillargs);
5319 			if (err < 0)
5320 				break;
5321 		}
5322 		break;
5323 	case ANYCAST_ADDR:
5324 		fillargs->event = RTM_GETANYCAST;
5325 		/* anycast address */
5326 		for (ifaca = rcu_dereference(idev->ac_list); ifaca;
5327 		     ifaca = rcu_dereference(ifaca->aca_next), ip_idx++) {
5328 			if (ip_idx < *s_ip_idx)
5329 				continue;
5330 			err = inet6_fill_ifacaddr(skb, ifaca, fillargs);
5331 			if (err < 0)
5332 				break;
5333 		}
5334 		break;
5335 	default:
5336 		break;
5337 	}
5338 	*s_ip_idx = err ? ip_idx : 0;
5339 	return err;
5340 }
5341 
inet6_valid_dump_ifaddr_req(const struct nlmsghdr * nlh,struct inet6_fill_args * fillargs,struct net ** tgt_net,struct sock * sk,struct netlink_callback * cb)5342 static int inet6_valid_dump_ifaddr_req(const struct nlmsghdr *nlh,
5343 				       struct inet6_fill_args *fillargs,
5344 				       struct net **tgt_net, struct sock *sk,
5345 				       struct netlink_callback *cb)
5346 {
5347 	struct netlink_ext_ack *extack = cb->extack;
5348 	struct nlattr *tb[IFA_MAX+1];
5349 	struct ifaddrmsg *ifm;
5350 	int err, i;
5351 
5352 	ifm = nlmsg_payload(nlh, sizeof(*ifm));
5353 	if (!ifm) {
5354 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for address dump request");
5355 		return -EINVAL;
5356 	}
5357 
5358 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5359 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for address dump request");
5360 		return -EINVAL;
5361 	}
5362 
5363 	fillargs->ifindex = ifm->ifa_index;
5364 	if (fillargs->ifindex) {
5365 		cb->answer_flags |= NLM_F_DUMP_FILTERED;
5366 		fillargs->flags |= NLM_F_DUMP_FILTERED;
5367 	}
5368 
5369 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5370 					    ifa_ipv6_policy, extack);
5371 	if (err < 0)
5372 		return err;
5373 
5374 	for (i = 0; i <= IFA_MAX; ++i) {
5375 		if (!tb[i])
5376 			continue;
5377 
5378 		if (i == IFA_TARGET_NETNSID) {
5379 			struct net *net;
5380 
5381 			fillargs->netnsid = nla_get_s32(tb[i]);
5382 			net = rtnl_get_net_ns_capable(sk, fillargs->netnsid);
5383 			if (IS_ERR(net)) {
5384 				fillargs->netnsid = -1;
5385 				NL_SET_ERR_MSG_MOD(extack, "Invalid target network namespace id");
5386 				return PTR_ERR(net);
5387 			}
5388 			*tgt_net = net;
5389 		} else {
5390 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in dump request");
5391 			return -EINVAL;
5392 		}
5393 	}
5394 
5395 	return 0;
5396 }
5397 
inet6_dump_addr(struct sk_buff * skb,struct netlink_callback * cb,enum addr_type_t type)5398 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
5399 			   enum addr_type_t type)
5400 {
5401 	struct net *tgt_net = sock_net(skb->sk);
5402 	const struct nlmsghdr *nlh = cb->nlh;
5403 	struct inet6_fill_args fillargs = {
5404 		.portid = NETLINK_CB(cb->skb).portid,
5405 		.seq = cb->nlh->nlmsg_seq,
5406 		.flags = NLM_F_MULTI,
5407 		.netnsid = -1,
5408 		.type = type,
5409 		.force_rt_scope_universe = false,
5410 	};
5411 	struct {
5412 		unsigned long ifindex;
5413 		int ip_idx;
5414 	} *ctx = (void *)cb->ctx;
5415 	struct net_device *dev;
5416 	struct inet6_dev *idev;
5417 	int err = 0;
5418 
5419 	rcu_read_lock();
5420 	if (cb->strict_check) {
5421 		err = inet6_valid_dump_ifaddr_req(nlh, &fillargs, &tgt_net,
5422 						  skb->sk, cb);
5423 		if (err < 0)
5424 			goto done;
5425 
5426 		err = 0;
5427 		if (fillargs.ifindex) {
5428 			dev = dev_get_by_index_rcu(tgt_net, fillargs.ifindex);
5429 			if (!dev) {
5430 				err = -ENODEV;
5431 				goto done;
5432 			}
5433 			idev = __in6_dev_get(dev);
5434 			if (idev)
5435 				err = in6_dump_addrs(idev, skb, cb,
5436 						     &ctx->ip_idx,
5437 						     &fillargs);
5438 			goto done;
5439 		}
5440 	}
5441 
5442 	cb->seq = inet6_base_seq(tgt_net);
5443 	for_each_netdev_dump(tgt_net, dev, ctx->ifindex) {
5444 		idev = __in6_dev_get(dev);
5445 		if (!idev)
5446 			continue;
5447 		err = in6_dump_addrs(idev, skb, cb, &ctx->ip_idx,
5448 				     &fillargs);
5449 		if (err < 0)
5450 			goto done;
5451 	}
5452 done:
5453 	rcu_read_unlock();
5454 	if (fillargs.netnsid >= 0)
5455 		put_net(tgt_net);
5456 
5457 	return err;
5458 }
5459 
inet6_dump_ifaddr(struct sk_buff * skb,struct netlink_callback * cb)5460 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
5461 {
5462 	enum addr_type_t type = UNICAST_ADDR;
5463 
5464 	return inet6_dump_addr(skb, cb, type);
5465 }
5466 
inet6_dump_ifmcaddr(struct sk_buff * skb,struct netlink_callback * cb)5467 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
5468 {
5469 	enum addr_type_t type = MULTICAST_ADDR;
5470 
5471 	return inet6_dump_addr(skb, cb, type);
5472 }
5473 
5474 
inet6_dump_ifacaddr(struct sk_buff * skb,struct netlink_callback * cb)5475 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
5476 {
5477 	enum addr_type_t type = ANYCAST_ADDR;
5478 
5479 	return inet6_dump_addr(skb, cb, type);
5480 }
5481 
inet6_rtm_valid_getaddr_req(struct sk_buff * skb,const struct nlmsghdr * nlh,struct nlattr ** tb,struct netlink_ext_ack * extack)5482 static int inet6_rtm_valid_getaddr_req(struct sk_buff *skb,
5483 				       const struct nlmsghdr *nlh,
5484 				       struct nlattr **tb,
5485 				       struct netlink_ext_ack *extack)
5486 {
5487 	struct ifaddrmsg *ifm;
5488 	int i, err;
5489 
5490 	ifm = nlmsg_payload(nlh, sizeof(*ifm));
5491 	if (!ifm) {
5492 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for get address request");
5493 		return -EINVAL;
5494 	}
5495 
5496 	if (!netlink_strict_get_check(skb))
5497 		return nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
5498 					      ifa_ipv6_policy, extack);
5499 
5500 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5501 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for get address request");
5502 		return -EINVAL;
5503 	}
5504 
5505 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5506 					    ifa_ipv6_policy, extack);
5507 	if (err)
5508 		return err;
5509 
5510 	for (i = 0; i <= IFA_MAX; i++) {
5511 		if (!tb[i])
5512 			continue;
5513 
5514 		switch (i) {
5515 		case IFA_TARGET_NETNSID:
5516 		case IFA_ADDRESS:
5517 		case IFA_LOCAL:
5518 			break;
5519 		default:
5520 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in get address request");
5521 			return -EINVAL;
5522 		}
5523 	}
5524 
5525 	return 0;
5526 }
5527 
inet6_rtm_getaddr(struct sk_buff * in_skb,struct nlmsghdr * nlh,struct netlink_ext_ack * extack)5528 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
5529 			     struct netlink_ext_ack *extack)
5530 {
5531 	struct net *tgt_net = sock_net(in_skb->sk);
5532 	struct inet6_fill_args fillargs = {
5533 		.portid = NETLINK_CB(in_skb).portid,
5534 		.seq = nlh->nlmsg_seq,
5535 		.event = RTM_NEWADDR,
5536 		.flags = 0,
5537 		.netnsid = -1,
5538 		.force_rt_scope_universe = false,
5539 	};
5540 	struct ifaddrmsg *ifm;
5541 	struct nlattr *tb[IFA_MAX+1];
5542 	struct in6_addr *addr = NULL, *peer;
5543 	struct net_device *dev = NULL;
5544 	struct inet6_ifaddr *ifa;
5545 	struct sk_buff *skb;
5546 	int err;
5547 
5548 	err = inet6_rtm_valid_getaddr_req(in_skb, nlh, tb, extack);
5549 	if (err < 0)
5550 		return err;
5551 
5552 	if (tb[IFA_TARGET_NETNSID]) {
5553 		fillargs.netnsid = nla_get_s32(tb[IFA_TARGET_NETNSID]);
5554 
5555 		tgt_net = rtnl_get_net_ns_capable(NETLINK_CB(in_skb).sk,
5556 						  fillargs.netnsid);
5557 		if (IS_ERR(tgt_net))
5558 			return PTR_ERR(tgt_net);
5559 	}
5560 
5561 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
5562 	if (!addr) {
5563 		err = -EINVAL;
5564 		goto errout;
5565 	}
5566 	ifm = nlmsg_data(nlh);
5567 	if (ifm->ifa_index)
5568 		dev = dev_get_by_index(tgt_net, ifm->ifa_index);
5569 
5570 	ifa = ipv6_get_ifaddr(tgt_net, addr, dev, 1);
5571 	if (!ifa) {
5572 		err = -EADDRNOTAVAIL;
5573 		goto errout;
5574 	}
5575 
5576 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
5577 	if (!skb) {
5578 		err = -ENOBUFS;
5579 		goto errout_ifa;
5580 	}
5581 
5582 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5583 	if (err < 0) {
5584 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5585 		WARN_ON(err == -EMSGSIZE);
5586 		kfree_skb(skb);
5587 		goto errout_ifa;
5588 	}
5589 	err = rtnl_unicast(skb, tgt_net, NETLINK_CB(in_skb).portid);
5590 errout_ifa:
5591 	in6_ifa_put(ifa);
5592 errout:
5593 	dev_put(dev);
5594 	if (fillargs.netnsid >= 0)
5595 		put_net(tgt_net);
5596 
5597 	return err;
5598 }
5599 
inet6_ifa_notify(int event,struct inet6_ifaddr * ifa)5600 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
5601 {
5602 	struct sk_buff *skb;
5603 	struct net *net = dev_net(ifa->idev->dev);
5604 	struct inet6_fill_args fillargs = {
5605 		.portid = 0,
5606 		.seq = 0,
5607 		.event = event,
5608 		.flags = 0,
5609 		.netnsid = -1,
5610 		.force_rt_scope_universe = false,
5611 	};
5612 	int err = -ENOBUFS;
5613 
5614 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
5615 	if (!skb)
5616 		goto errout;
5617 
5618 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5619 	if (err < 0) {
5620 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5621 		WARN_ON(err == -EMSGSIZE);
5622 		kfree_skb(skb);
5623 		goto errout;
5624 	}
5625 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
5626 	return;
5627 errout:
5628 	rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
5629 }
5630 
ipv6_store_devconf(const struct ipv6_devconf * cnf,__s32 * array,int bytes)5631 static void ipv6_store_devconf(const struct ipv6_devconf *cnf,
5632 			       __s32 *array, int bytes)
5633 {
5634 	BUG_ON(bytes < (DEVCONF_MAX * 4));
5635 
5636 	memset(array, 0, bytes);
5637 	array[DEVCONF_FORWARDING] = READ_ONCE(cnf->forwarding);
5638 	array[DEVCONF_HOPLIMIT] = READ_ONCE(cnf->hop_limit);
5639 	array[DEVCONF_MTU6] = READ_ONCE(cnf->mtu6);
5640 	array[DEVCONF_ACCEPT_RA] = READ_ONCE(cnf->accept_ra);
5641 	array[DEVCONF_ACCEPT_REDIRECTS] = READ_ONCE(cnf->accept_redirects);
5642 	array[DEVCONF_AUTOCONF] = READ_ONCE(cnf->autoconf);
5643 	array[DEVCONF_DAD_TRANSMITS] = READ_ONCE(cnf->dad_transmits);
5644 	array[DEVCONF_RTR_SOLICITS] = READ_ONCE(cnf->rtr_solicits);
5645 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
5646 		jiffies_to_msecs(READ_ONCE(cnf->rtr_solicit_interval));
5647 	array[DEVCONF_RTR_SOLICIT_MAX_INTERVAL] =
5648 		jiffies_to_msecs(READ_ONCE(cnf->rtr_solicit_max_interval));
5649 	array[DEVCONF_RTR_SOLICIT_DELAY] =
5650 		jiffies_to_msecs(READ_ONCE(cnf->rtr_solicit_delay));
5651 	array[DEVCONF_FORCE_MLD_VERSION] = READ_ONCE(cnf->force_mld_version);
5652 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
5653 		jiffies_to_msecs(READ_ONCE(cnf->mldv1_unsolicited_report_interval));
5654 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
5655 		jiffies_to_msecs(READ_ONCE(cnf->mldv2_unsolicited_report_interval));
5656 	array[DEVCONF_USE_TEMPADDR] = READ_ONCE(cnf->use_tempaddr);
5657 	array[DEVCONF_TEMP_VALID_LFT] = READ_ONCE(cnf->temp_valid_lft);
5658 	array[DEVCONF_TEMP_PREFERED_LFT] = READ_ONCE(cnf->temp_prefered_lft);
5659 	array[DEVCONF_REGEN_MAX_RETRY] = READ_ONCE(cnf->regen_max_retry);
5660 	array[DEVCONF_MAX_DESYNC_FACTOR] = READ_ONCE(cnf->max_desync_factor);
5661 	array[DEVCONF_MAX_ADDRESSES] = READ_ONCE(cnf->max_addresses);
5662 	array[DEVCONF_ACCEPT_RA_DEFRTR] = READ_ONCE(cnf->accept_ra_defrtr);
5663 	array[DEVCONF_RA_DEFRTR_METRIC] = READ_ONCE(cnf->ra_defrtr_metric);
5664 	array[DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT] =
5665 		READ_ONCE(cnf->accept_ra_min_hop_limit);
5666 	array[DEVCONF_ACCEPT_RA_PINFO] = READ_ONCE(cnf->accept_ra_pinfo);
5667 #ifdef CONFIG_IPV6_ROUTER_PREF
5668 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = READ_ONCE(cnf->accept_ra_rtr_pref);
5669 	array[DEVCONF_RTR_PROBE_INTERVAL] =
5670 		jiffies_to_msecs(READ_ONCE(cnf->rtr_probe_interval));
5671 #ifdef CONFIG_IPV6_ROUTE_INFO
5672 	array[DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN] =
5673 		READ_ONCE(cnf->accept_ra_rt_info_min_plen);
5674 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] =
5675 		READ_ONCE(cnf->accept_ra_rt_info_max_plen);
5676 #endif
5677 #endif
5678 	array[DEVCONF_PROXY_NDP] = READ_ONCE(cnf->proxy_ndp);
5679 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] =
5680 		READ_ONCE(cnf->accept_source_route);
5681 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5682 	array[DEVCONF_OPTIMISTIC_DAD] = READ_ONCE(cnf->optimistic_dad);
5683 	array[DEVCONF_USE_OPTIMISTIC] = READ_ONCE(cnf->use_optimistic);
5684 #endif
5685 #ifdef CONFIG_IPV6_MROUTE
5686 	array[DEVCONF_MC_FORWARDING] = atomic_read(&cnf->mc_forwarding);
5687 #endif
5688 	array[DEVCONF_DISABLE_IPV6] = READ_ONCE(cnf->disable_ipv6);
5689 	array[DEVCONF_ACCEPT_DAD] = READ_ONCE(cnf->accept_dad);
5690 	array[DEVCONF_FORCE_TLLAO] = READ_ONCE(cnf->force_tllao);
5691 	array[DEVCONF_NDISC_NOTIFY] = READ_ONCE(cnf->ndisc_notify);
5692 	array[DEVCONF_SUPPRESS_FRAG_NDISC] =
5693 		READ_ONCE(cnf->suppress_frag_ndisc);
5694 	array[DEVCONF_ACCEPT_RA_FROM_LOCAL] =
5695 		READ_ONCE(cnf->accept_ra_from_local);
5696 	array[DEVCONF_ACCEPT_RA_MTU] = READ_ONCE(cnf->accept_ra_mtu);
5697 	array[DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN] =
5698 		READ_ONCE(cnf->ignore_routes_with_linkdown);
5699 	/* we omit DEVCONF_STABLE_SECRET for now */
5700 	array[DEVCONF_USE_OIF_ADDRS_ONLY] = READ_ONCE(cnf->use_oif_addrs_only);
5701 	array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] =
5702 		READ_ONCE(cnf->drop_unicast_in_l2_multicast);
5703 	array[DEVCONF_DROP_UNSOLICITED_NA] = READ_ONCE(cnf->drop_unsolicited_na);
5704 	array[DEVCONF_KEEP_ADDR_ON_DOWN] = READ_ONCE(cnf->keep_addr_on_down);
5705 	array[DEVCONF_SEG6_ENABLED] = READ_ONCE(cnf->seg6_enabled);
5706 #ifdef CONFIG_IPV6_SEG6_HMAC
5707 	array[DEVCONF_SEG6_REQUIRE_HMAC] = READ_ONCE(cnf->seg6_require_hmac);
5708 #endif
5709 	array[DEVCONF_ENHANCED_DAD] = READ_ONCE(cnf->enhanced_dad);
5710 	array[DEVCONF_ADDR_GEN_MODE] = READ_ONCE(cnf->addr_gen_mode);
5711 	array[DEVCONF_DISABLE_POLICY] = READ_ONCE(cnf->disable_policy);
5712 	array[DEVCONF_NDISC_TCLASS] = READ_ONCE(cnf->ndisc_tclass);
5713 	array[DEVCONF_RPL_SEG_ENABLED] = READ_ONCE(cnf->rpl_seg_enabled);
5714 	array[DEVCONF_IOAM6_ENABLED] = READ_ONCE(cnf->ioam6_enabled);
5715 	array[DEVCONF_IOAM6_ID] = READ_ONCE(cnf->ioam6_id);
5716 	array[DEVCONF_IOAM6_ID_WIDE] = READ_ONCE(cnf->ioam6_id_wide);
5717 	array[DEVCONF_NDISC_EVICT_NOCARRIER] =
5718 		READ_ONCE(cnf->ndisc_evict_nocarrier);
5719 	array[DEVCONF_ACCEPT_UNTRACKED_NA] =
5720 		READ_ONCE(cnf->accept_untracked_na);
5721 	array[DEVCONF_ACCEPT_RA_MIN_LFT] = READ_ONCE(cnf->accept_ra_min_lft);
5722 }
5723 
inet6_ifla6_size(void)5724 static inline size_t inet6_ifla6_size(void)
5725 {
5726 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
5727 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
5728 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
5729 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
5730 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
5731 	     + nla_total_size(sizeof(struct in6_addr)) /* IFLA_INET6_TOKEN */
5732 	     + nla_total_size(1) /* IFLA_INET6_ADDR_GEN_MODE */
5733 	     + nla_total_size(4) /* IFLA_INET6_RA_MTU */
5734 	     + 0;
5735 }
5736 
inet6_if_nlmsg_size(void)5737 static inline size_t inet6_if_nlmsg_size(void)
5738 {
5739 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
5740 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
5741 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
5742 	       + nla_total_size(4) /* IFLA_MTU */
5743 	       + nla_total_size(4) /* IFLA_LINK */
5744 	       + nla_total_size(1) /* IFLA_OPERSTATE */
5745 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
5746 }
5747 
__snmp6_fill_statsdev(u64 * stats,atomic_long_t * mib,int bytes)5748 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
5749 					int bytes)
5750 {
5751 	int i;
5752 	int pad = bytes - sizeof(u64) * ICMP6_MIB_MAX;
5753 	BUG_ON(pad < 0);
5754 
5755 	/* Use put_unaligned() because stats may not be aligned for u64. */
5756 	put_unaligned(ICMP6_MIB_MAX, &stats[0]);
5757 	for (i = 1; i < ICMP6_MIB_MAX; i++)
5758 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
5759 
5760 	memset(&stats[ICMP6_MIB_MAX], 0, pad);
5761 }
5762 
__snmp6_fill_stats64(u64 * stats,void __percpu * mib,int bytes,size_t syncpoff)5763 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
5764 					int bytes, size_t syncpoff)
5765 {
5766 	int i, c;
5767 	u64 buff[IPSTATS_MIB_MAX];
5768 	int pad = bytes - sizeof(u64) * IPSTATS_MIB_MAX;
5769 
5770 	BUG_ON(pad < 0);
5771 
5772 	memset(buff, 0, sizeof(buff));
5773 	buff[0] = IPSTATS_MIB_MAX;
5774 
5775 	for_each_possible_cpu(c) {
5776 		for (i = 1; i < IPSTATS_MIB_MAX; i++)
5777 			buff[i] += snmp_get_cpu_field64(mib, c, i, syncpoff);
5778 	}
5779 
5780 	memcpy(stats, buff, IPSTATS_MIB_MAX * sizeof(u64));
5781 	memset(&stats[IPSTATS_MIB_MAX], 0, pad);
5782 }
5783 
snmp6_fill_stats(u64 * stats,struct inet6_dev * idev,int attrtype,int bytes)5784 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
5785 			     int bytes)
5786 {
5787 	switch (attrtype) {
5788 	case IFLA_INET6_STATS:
5789 		__snmp6_fill_stats64(stats, idev->stats.ipv6, bytes,
5790 				     offsetof(struct ipstats_mib, syncp));
5791 		break;
5792 	case IFLA_INET6_ICMP6STATS:
5793 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, bytes);
5794 		break;
5795 	}
5796 }
5797 
inet6_fill_ifla6_stats_attrs(struct sk_buff * skb,struct inet6_dev * idev)5798 static int inet6_fill_ifla6_stats_attrs(struct sk_buff *skb,
5799 					struct inet6_dev *idev)
5800 {
5801 	struct nlattr *nla;
5802 
5803 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
5804 	if (!nla)
5805 		goto nla_put_failure;
5806 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
5807 
5808 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
5809 	if (!nla)
5810 		goto nla_put_failure;
5811 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
5812 
5813 	return 0;
5814 
5815 nla_put_failure:
5816 	return -EMSGSIZE;
5817 }
5818 
inet6_fill_ifla6_attrs(struct sk_buff * skb,struct inet6_dev * idev,u32 ext_filter_mask)5819 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev,
5820 				  u32 ext_filter_mask)
5821 {
5822 	struct ifla_cacheinfo ci;
5823 	struct nlattr *nla;
5824 	u32 ra_mtu;
5825 
5826 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, READ_ONCE(idev->if_flags)))
5827 		goto nla_put_failure;
5828 	ci.max_reasm_len = IPV6_MAXPLEN;
5829 	ci.tstamp = cstamp_delta(READ_ONCE(idev->tstamp));
5830 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
5831 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
5832 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
5833 		goto nla_put_failure;
5834 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
5835 	if (!nla)
5836 		goto nla_put_failure;
5837 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
5838 
5839 	/* XXX - MC not implemented */
5840 
5841 	if (!(ext_filter_mask & RTEXT_FILTER_SKIP_STATS)) {
5842 		if (inet6_fill_ifla6_stats_attrs(skb, idev) < 0)
5843 			goto nla_put_failure;
5844 	}
5845 
5846 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
5847 	if (!nla)
5848 		goto nla_put_failure;
5849 	read_lock_bh(&idev->lock);
5850 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
5851 	read_unlock_bh(&idev->lock);
5852 
5853 	if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE,
5854 		       READ_ONCE(idev->cnf.addr_gen_mode)))
5855 		goto nla_put_failure;
5856 
5857 	ra_mtu = READ_ONCE(idev->ra_mtu);
5858 	if (ra_mtu && nla_put_u32(skb, IFLA_INET6_RA_MTU, ra_mtu))
5859 		goto nla_put_failure;
5860 
5861 	return 0;
5862 
5863 nla_put_failure:
5864 	return -EMSGSIZE;
5865 }
5866 
inet6_get_link_af_size(const struct net_device * dev,u32 ext_filter_mask)5867 static size_t inet6_get_link_af_size(const struct net_device *dev,
5868 				     u32 ext_filter_mask)
5869 {
5870 	if (!__in6_dev_get(dev))
5871 		return 0;
5872 
5873 	return inet6_ifla6_size();
5874 }
5875 
inet6_fill_link_af(struct sk_buff * skb,const struct net_device * dev,u32 ext_filter_mask)5876 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
5877 			      u32 ext_filter_mask)
5878 {
5879 	struct inet6_dev *idev = __in6_dev_get(dev);
5880 
5881 	if (!idev)
5882 		return -ENODATA;
5883 
5884 	if (inet6_fill_ifla6_attrs(skb, idev, ext_filter_mask) < 0)
5885 		return -EMSGSIZE;
5886 
5887 	return 0;
5888 }
5889 
inet6_set_iftoken(struct inet6_dev * idev,struct in6_addr * token,struct netlink_ext_ack * extack)5890 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token,
5891 			     struct netlink_ext_ack *extack)
5892 {
5893 	struct inet6_ifaddr *ifp;
5894 	struct net_device *dev = idev->dev;
5895 	bool clear_token, update_rs = false;
5896 	struct in6_addr ll_addr;
5897 
5898 	ASSERT_RTNL();
5899 
5900 	if (!token)
5901 		return -EINVAL;
5902 
5903 	if (dev->flags & IFF_LOOPBACK) {
5904 		NL_SET_ERR_MSG_MOD(extack, "Device is loopback");
5905 		return -EINVAL;
5906 	}
5907 
5908 	if (dev->flags & IFF_NOARP) {
5909 		NL_SET_ERR_MSG_MOD(extack,
5910 				   "Device does not do neighbour discovery");
5911 		return -EINVAL;
5912 	}
5913 
5914 	if (!ipv6_accept_ra(idev)) {
5915 		NL_SET_ERR_MSG_MOD(extack,
5916 				   "Router advertisement is disabled on device");
5917 		return -EINVAL;
5918 	}
5919 
5920 	if (READ_ONCE(idev->cnf.rtr_solicits) == 0) {
5921 		NL_SET_ERR_MSG(extack,
5922 			       "Router solicitation is disabled on device");
5923 		return -EINVAL;
5924 	}
5925 
5926 	write_lock_bh(&idev->lock);
5927 
5928 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
5929 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
5930 
5931 	write_unlock_bh(&idev->lock);
5932 
5933 	clear_token = ipv6_addr_any(token);
5934 	if (clear_token)
5935 		goto update_lft;
5936 
5937 	if (!idev->dead && (idev->if_flags & IF_READY) &&
5938 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
5939 			     IFA_F_OPTIMISTIC)) {
5940 		/* If we're not ready, then normal ifup will take care
5941 		 * of this. Otherwise, we need to request our rs here.
5942 		 */
5943 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
5944 		update_rs = true;
5945 	}
5946 
5947 update_lft:
5948 	write_lock_bh(&idev->lock);
5949 
5950 	if (update_rs) {
5951 		idev->if_flags |= IF_RS_SENT;
5952 		idev->rs_interval = rfc3315_s14_backoff_init(
5953 			READ_ONCE(idev->cnf.rtr_solicit_interval));
5954 		idev->rs_probes = 1;
5955 		addrconf_mod_rs_timer(idev, idev->rs_interval);
5956 	}
5957 
5958 	/* Well, that's kinda nasty ... */
5959 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
5960 		spin_lock(&ifp->lock);
5961 		if (ifp->tokenized) {
5962 			ifp->valid_lft = 0;
5963 			ifp->prefered_lft = 0;
5964 		}
5965 		spin_unlock(&ifp->lock);
5966 	}
5967 
5968 	write_unlock_bh(&idev->lock);
5969 	inet6_ifinfo_notify(RTM_NEWLINK, idev);
5970 	addrconf_verify_rtnl(dev_net(dev));
5971 	return 0;
5972 }
5973 
5974 static const struct nla_policy inet6_af_policy[IFLA_INET6_MAX + 1] = {
5975 	[IFLA_INET6_ADDR_GEN_MODE]	= { .type = NLA_U8 },
5976 	[IFLA_INET6_TOKEN]		= { .len = sizeof(struct in6_addr) },
5977 	[IFLA_INET6_RA_MTU]		= { .type = NLA_REJECT,
5978 					    .reject_message =
5979 						"IFLA_INET6_RA_MTU can not be set" },
5980 };
5981 
check_addr_gen_mode(int mode)5982 static int check_addr_gen_mode(int mode)
5983 {
5984 	if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
5985 	    mode != IN6_ADDR_GEN_MODE_NONE &&
5986 	    mode != IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5987 	    mode != IN6_ADDR_GEN_MODE_RANDOM)
5988 		return -EINVAL;
5989 	return 1;
5990 }
5991 
check_stable_privacy(struct inet6_dev * idev,struct net * net,int mode)5992 static int check_stable_privacy(struct inet6_dev *idev, struct net *net,
5993 				int mode)
5994 {
5995 	if (mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5996 	    !idev->cnf.stable_secret.initialized &&
5997 	    !net->ipv6.devconf_dflt->stable_secret.initialized)
5998 		return -EINVAL;
5999 	return 1;
6000 }
6001 
inet6_validate_link_af(const struct net_device * dev,const struct nlattr * nla,struct netlink_ext_ack * extack)6002 static int inet6_validate_link_af(const struct net_device *dev,
6003 				  const struct nlattr *nla,
6004 				  struct netlink_ext_ack *extack)
6005 {
6006 	struct nlattr *tb[IFLA_INET6_MAX + 1];
6007 	struct inet6_dev *idev = NULL;
6008 	int err;
6009 
6010 	if (dev) {
6011 		idev = __in6_dev_get(dev);
6012 		if (!idev)
6013 			return -EAFNOSUPPORT;
6014 	}
6015 
6016 	err = nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla,
6017 					  inet6_af_policy, extack);
6018 	if (err)
6019 		return err;
6020 
6021 	if (!tb[IFLA_INET6_TOKEN] && !tb[IFLA_INET6_ADDR_GEN_MODE])
6022 		return -EINVAL;
6023 
6024 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
6025 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
6026 
6027 		if (check_addr_gen_mode(mode) < 0)
6028 			return -EINVAL;
6029 		if (dev && check_stable_privacy(idev, dev_net(dev), mode) < 0)
6030 			return -EINVAL;
6031 	}
6032 
6033 	return 0;
6034 }
6035 
inet6_set_link_af(struct net_device * dev,const struct nlattr * nla,struct netlink_ext_ack * extack)6036 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla,
6037 			     struct netlink_ext_ack *extack)
6038 {
6039 	struct inet6_dev *idev = __in6_dev_get(dev);
6040 	struct nlattr *tb[IFLA_INET6_MAX + 1];
6041 	int err;
6042 
6043 	if (!idev)
6044 		return -EAFNOSUPPORT;
6045 
6046 	if (nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla, NULL, NULL) < 0)
6047 		return -EINVAL;
6048 
6049 	if (tb[IFLA_INET6_TOKEN]) {
6050 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]),
6051 					extack);
6052 		if (err)
6053 			return err;
6054 	}
6055 
6056 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
6057 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
6058 
6059 		WRITE_ONCE(idev->cnf.addr_gen_mode, mode);
6060 	}
6061 
6062 	return 0;
6063 }
6064 
inet6_fill_ifinfo(struct sk_buff * skb,struct inet6_dev * idev,u32 portid,u32 seq,int event,unsigned int flags)6065 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
6066 			     u32 portid, u32 seq, int event, unsigned int flags)
6067 {
6068 	struct net_device *dev = idev->dev;
6069 	struct ifinfomsg *hdr;
6070 	struct nlmsghdr *nlh;
6071 	int ifindex, iflink;
6072 	void *protoinfo;
6073 
6074 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
6075 	if (!nlh)
6076 		return -EMSGSIZE;
6077 
6078 	hdr = nlmsg_data(nlh);
6079 	hdr->ifi_family = AF_INET6;
6080 	hdr->__ifi_pad = 0;
6081 	hdr->ifi_type = dev->type;
6082 	ifindex = READ_ONCE(dev->ifindex);
6083 	hdr->ifi_index = ifindex;
6084 	hdr->ifi_flags = dev_get_flags(dev);
6085 	hdr->ifi_change = 0;
6086 
6087 	iflink = dev_get_iflink(dev);
6088 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
6089 	    (dev->addr_len &&
6090 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
6091 	    nla_put_u32(skb, IFLA_MTU, READ_ONCE(dev->mtu)) ||
6092 	    (ifindex != iflink &&
6093 	     nla_put_u32(skb, IFLA_LINK, iflink)) ||
6094 	    nla_put_u8(skb, IFLA_OPERSTATE,
6095 		       netif_running(dev) ? READ_ONCE(dev->operstate) : IF_OPER_DOWN))
6096 		goto nla_put_failure;
6097 	protoinfo = nla_nest_start_noflag(skb, IFLA_PROTINFO);
6098 	if (!protoinfo)
6099 		goto nla_put_failure;
6100 
6101 	if (inet6_fill_ifla6_attrs(skb, idev, 0) < 0)
6102 		goto nla_put_failure;
6103 
6104 	nla_nest_end(skb, protoinfo);
6105 	nlmsg_end(skb, nlh);
6106 	return 0;
6107 
6108 nla_put_failure:
6109 	nlmsg_cancel(skb, nlh);
6110 	return -EMSGSIZE;
6111 }
6112 
inet6_valid_dump_ifinfo(const struct nlmsghdr * nlh,struct netlink_ext_ack * extack)6113 static int inet6_valid_dump_ifinfo(const struct nlmsghdr *nlh,
6114 				   struct netlink_ext_ack *extack)
6115 {
6116 	struct ifinfomsg *ifm;
6117 
6118 	ifm = nlmsg_payload(nlh, sizeof(*ifm));
6119 	if (!ifm) {
6120 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for link dump request");
6121 		return -EINVAL;
6122 	}
6123 
6124 	if (nlmsg_attrlen(nlh, sizeof(*ifm))) {
6125 		NL_SET_ERR_MSG_MOD(extack, "Invalid data after header");
6126 		return -EINVAL;
6127 	}
6128 
6129 	if (ifm->__ifi_pad || ifm->ifi_type || ifm->ifi_flags ||
6130 	    ifm->ifi_change || ifm->ifi_index) {
6131 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for dump request");
6132 		return -EINVAL;
6133 	}
6134 
6135 	return 0;
6136 }
6137 
inet6_dump_ifinfo(struct sk_buff * skb,struct netlink_callback * cb)6138 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
6139 {
6140 	struct net *net = sock_net(skb->sk);
6141 	struct {
6142 		unsigned long ifindex;
6143 	} *ctx = (void *)cb->ctx;
6144 	struct net_device *dev;
6145 	struct inet6_dev *idev;
6146 	int err;
6147 
6148 	/* only requests using strict checking can pass data to
6149 	 * influence the dump
6150 	 */
6151 	if (cb->strict_check) {
6152 		err = inet6_valid_dump_ifinfo(cb->nlh, cb->extack);
6153 
6154 		if (err < 0)
6155 			return err;
6156 	}
6157 
6158 	err = 0;
6159 	rcu_read_lock();
6160 	for_each_netdev_dump(net, dev, ctx->ifindex) {
6161 		idev = __in6_dev_get(dev);
6162 		if (!idev)
6163 			continue;
6164 		err = inet6_fill_ifinfo(skb, idev,
6165 					NETLINK_CB(cb->skb).portid,
6166 					cb->nlh->nlmsg_seq,
6167 					RTM_NEWLINK, NLM_F_MULTI);
6168 		if (err < 0)
6169 			break;
6170 	}
6171 	rcu_read_unlock();
6172 
6173 	return err;
6174 }
6175 
inet6_ifinfo_notify(int event,struct inet6_dev * idev)6176 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
6177 {
6178 	struct sk_buff *skb;
6179 	struct net *net = dev_net(idev->dev);
6180 	int err = -ENOBUFS;
6181 
6182 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
6183 	if (!skb)
6184 		goto errout;
6185 
6186 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
6187 	if (err < 0) {
6188 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
6189 		WARN_ON(err == -EMSGSIZE);
6190 		kfree_skb(skb);
6191 		goto errout;
6192 	}
6193 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
6194 	return;
6195 errout:
6196 	rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
6197 }
6198 
inet6_prefix_nlmsg_size(void)6199 static inline size_t inet6_prefix_nlmsg_size(void)
6200 {
6201 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
6202 	       + nla_total_size(sizeof(struct in6_addr))
6203 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
6204 }
6205 
inet6_fill_prefix(struct sk_buff * skb,struct inet6_dev * idev,struct prefix_info * pinfo,u32 portid,u32 seq,int event,unsigned int flags)6206 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
6207 			     struct prefix_info *pinfo, u32 portid, u32 seq,
6208 			     int event, unsigned int flags)
6209 {
6210 	struct prefixmsg *pmsg;
6211 	struct nlmsghdr *nlh;
6212 	struct prefix_cacheinfo	ci;
6213 
6214 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
6215 	if (!nlh)
6216 		return -EMSGSIZE;
6217 
6218 	pmsg = nlmsg_data(nlh);
6219 	pmsg->prefix_family = AF_INET6;
6220 	pmsg->prefix_pad1 = 0;
6221 	pmsg->prefix_pad2 = 0;
6222 	pmsg->prefix_ifindex = idev->dev->ifindex;
6223 	pmsg->prefix_len = pinfo->prefix_len;
6224 	pmsg->prefix_type = pinfo->type;
6225 	pmsg->prefix_pad3 = 0;
6226 	pmsg->prefix_flags = pinfo->flags;
6227 
6228 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
6229 		goto nla_put_failure;
6230 	ci.preferred_time = ntohl(pinfo->prefered);
6231 	ci.valid_time = ntohl(pinfo->valid);
6232 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
6233 		goto nla_put_failure;
6234 	nlmsg_end(skb, nlh);
6235 	return 0;
6236 
6237 nla_put_failure:
6238 	nlmsg_cancel(skb, nlh);
6239 	return -EMSGSIZE;
6240 }
6241 
inet6_prefix_notify(int event,struct inet6_dev * idev,struct prefix_info * pinfo)6242 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
6243 			 struct prefix_info *pinfo)
6244 {
6245 	struct sk_buff *skb;
6246 	struct net *net = dev_net(idev->dev);
6247 	int err = -ENOBUFS;
6248 
6249 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
6250 	if (!skb)
6251 		goto errout;
6252 
6253 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
6254 	if (err < 0) {
6255 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
6256 		WARN_ON(err == -EMSGSIZE);
6257 		kfree_skb(skb);
6258 		goto errout;
6259 	}
6260 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
6261 	return;
6262 errout:
6263 	rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
6264 }
6265 
__ipv6_ifa_notify(int event,struct inet6_ifaddr * ifp)6266 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
6267 {
6268 	struct net *net = dev_net(ifp->idev->dev);
6269 
6270 	if (event)
6271 		ASSERT_RTNL();
6272 
6273 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
6274 
6275 	switch (event) {
6276 	case RTM_NEWADDR:
6277 		/*
6278 		 * If the address was optimistic we inserted the route at the
6279 		 * start of our DAD process, so we don't need to do it again.
6280 		 * If the device was taken down in the middle of the DAD
6281 		 * cycle there is a race where we could get here without a
6282 		 * host route, so nothing to insert. That will be fixed when
6283 		 * the device is brought up.
6284 		 */
6285 		if (ifp->rt && !rcu_access_pointer(ifp->rt->fib6_node)) {
6286 			ip6_ins_rt(net, ifp->rt);
6287 		} else if (!ifp->rt && (ifp->idev->dev->flags & IFF_UP)) {
6288 			pr_warn("BUG: Address %pI6c on device %s is missing its host route.\n",
6289 				&ifp->addr, ifp->idev->dev->name);
6290 		}
6291 
6292 		if (ifp->idev->cnf.forwarding)
6293 			addrconf_join_anycast(ifp);
6294 		if (!ipv6_addr_any(&ifp->peer_addr))
6295 			addrconf_prefix_route(&ifp->peer_addr, 128,
6296 					      ifp->rt_priority, ifp->idev->dev,
6297 					      0, 0, GFP_ATOMIC);
6298 		break;
6299 	case RTM_DELADDR:
6300 		if (ifp->idev->cnf.forwarding)
6301 			addrconf_leave_anycast(ifp);
6302 		addrconf_leave_solict(ifp->idev, &ifp->addr);
6303 		if (!ipv6_addr_any(&ifp->peer_addr)) {
6304 			struct fib6_info *rt;
6305 
6306 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
6307 						       ifp->idev->dev, 0, 0,
6308 						       false);
6309 			if (rt)
6310 				ip6_del_rt(net, rt, false);
6311 		}
6312 		if (ifp->rt) {
6313 			ip6_del_rt(net, ifp->rt, false);
6314 			ifp->rt = NULL;
6315 		}
6316 		rt_genid_bump_ipv6(net);
6317 		break;
6318 	}
6319 	atomic_inc(&net->ipv6.dev_addr_genid);
6320 }
6321 
ipv6_ifa_notify(int event,struct inet6_ifaddr * ifp)6322 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
6323 {
6324 	if (likely(ifp->idev->dead == 0))
6325 		__ipv6_ifa_notify(event, ifp);
6326 }
6327 
6328 #ifdef CONFIG_SYSCTL
6329 
addrconf_sysctl_forward(const struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)6330 static int addrconf_sysctl_forward(const struct ctl_table *ctl, int write,
6331 		void *buffer, size_t *lenp, loff_t *ppos)
6332 {
6333 	int *valp = ctl->data;
6334 	int val = *valp;
6335 	loff_t pos = *ppos;
6336 	struct ctl_table lctl;
6337 	int ret;
6338 
6339 	/*
6340 	 * ctl->data points to idev->cnf.forwarding, we should
6341 	 * not modify it until we get the rtnl lock.
6342 	 */
6343 	lctl = *ctl;
6344 	lctl.data = &val;
6345 
6346 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6347 
6348 	if (write)
6349 		ret = addrconf_fixup_forwarding(ctl, valp, val);
6350 	if (ret)
6351 		*ppos = pos;
6352 	return ret;
6353 }
6354 
addrconf_sysctl_mtu(const struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)6355 static int addrconf_sysctl_mtu(const struct ctl_table *ctl, int write,
6356 		void *buffer, size_t *lenp, loff_t *ppos)
6357 {
6358 	struct inet6_dev *idev = ctl->extra1;
6359 	int min_mtu = IPV6_MIN_MTU;
6360 	struct ctl_table lctl;
6361 
6362 	lctl = *ctl;
6363 	lctl.extra1 = &min_mtu;
6364 	lctl.extra2 = idev ? &idev->dev->mtu : NULL;
6365 
6366 	return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
6367 }
6368 
dev_disable_change(struct inet6_dev * idev)6369 static void dev_disable_change(struct inet6_dev *idev)
6370 {
6371 	struct netdev_notifier_info info;
6372 
6373 	if (!idev || !idev->dev)
6374 		return;
6375 
6376 	netdev_notifier_info_init(&info, idev->dev);
6377 	if (idev->cnf.disable_ipv6)
6378 		addrconf_notify(NULL, NETDEV_DOWN, &info);
6379 	else
6380 		addrconf_notify(NULL, NETDEV_UP, &info);
6381 }
6382 
addrconf_disable_change(struct net * net,__s32 newf)6383 static void addrconf_disable_change(struct net *net, __s32 newf)
6384 {
6385 	struct net_device *dev;
6386 	struct inet6_dev *idev;
6387 
6388 	for_each_netdev(net, dev) {
6389 		idev = __in6_dev_get_rtnl_net(dev);
6390 		if (idev) {
6391 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
6392 
6393 			WRITE_ONCE(idev->cnf.disable_ipv6, newf);
6394 			if (changed)
6395 				dev_disable_change(idev);
6396 		}
6397 	}
6398 }
6399 
addrconf_disable_ipv6(const struct ctl_table * table,int * p,int newf)6400 static int addrconf_disable_ipv6(const struct ctl_table *table, int *p, int newf)
6401 {
6402 	struct net *net = (struct net *)table->extra2;
6403 	int old;
6404 
6405 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
6406 		WRITE_ONCE(*p, newf);
6407 		return 0;
6408 	}
6409 
6410 	if (!rtnl_net_trylock(net))
6411 		return restart_syscall();
6412 
6413 	old = *p;
6414 	WRITE_ONCE(*p, newf);
6415 
6416 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
6417 		WRITE_ONCE(net->ipv6.devconf_dflt->disable_ipv6, newf);
6418 		addrconf_disable_change(net, newf);
6419 	} else if ((!newf) ^ (!old)) {
6420 		dev_disable_change((struct inet6_dev *)table->extra1);
6421 	}
6422 
6423 	rtnl_net_unlock(net);
6424 	return 0;
6425 }
6426 
addrconf_sysctl_disable(const struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)6427 static int addrconf_sysctl_disable(const struct ctl_table *ctl, int write,
6428 		void *buffer, size_t *lenp, loff_t *ppos)
6429 {
6430 	int *valp = ctl->data;
6431 	int val = *valp;
6432 	loff_t pos = *ppos;
6433 	struct ctl_table lctl;
6434 	int ret;
6435 
6436 	/*
6437 	 * ctl->data points to idev->cnf.disable_ipv6, we should
6438 	 * not modify it until we get the rtnl lock.
6439 	 */
6440 	lctl = *ctl;
6441 	lctl.data = &val;
6442 
6443 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6444 
6445 	if (write)
6446 		ret = addrconf_disable_ipv6(ctl, valp, val);
6447 	if (ret)
6448 		*ppos = pos;
6449 	return ret;
6450 }
6451 
addrconf_sysctl_proxy_ndp(const struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)6452 static int addrconf_sysctl_proxy_ndp(const struct ctl_table *ctl, int write,
6453 		void *buffer, size_t *lenp, loff_t *ppos)
6454 {
6455 	int *valp = ctl->data;
6456 	int ret;
6457 	int old, new;
6458 
6459 	old = *valp;
6460 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
6461 	new = *valp;
6462 
6463 	if (write && old != new) {
6464 		struct net *net = ctl->extra2;
6465 
6466 		if (!rtnl_net_trylock(net))
6467 			return restart_syscall();
6468 
6469 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp) {
6470 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6471 						     NETCONFA_PROXY_NEIGH,
6472 						     NETCONFA_IFINDEX_DEFAULT,
6473 						     net->ipv6.devconf_dflt);
6474 		} else if (valp == &net->ipv6.devconf_all->proxy_ndp) {
6475 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6476 						     NETCONFA_PROXY_NEIGH,
6477 						     NETCONFA_IFINDEX_ALL,
6478 						     net->ipv6.devconf_all);
6479 		} else {
6480 			struct inet6_dev *idev = ctl->extra1;
6481 
6482 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6483 						     NETCONFA_PROXY_NEIGH,
6484 						     idev->dev->ifindex,
6485 						     &idev->cnf);
6486 		}
6487 		rtnl_net_unlock(net);
6488 	}
6489 
6490 	return ret;
6491 }
6492 
addrconf_sysctl_addr_gen_mode(const struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)6493 static int addrconf_sysctl_addr_gen_mode(const struct ctl_table *ctl, int write,
6494 					 void *buffer, size_t *lenp,
6495 					 loff_t *ppos)
6496 {
6497 	int ret = 0;
6498 	u32 new_val;
6499 	struct inet6_dev *idev = (struct inet6_dev *)ctl->extra1;
6500 	struct net *net = (struct net *)ctl->extra2;
6501 	struct ctl_table tmp = {
6502 		.data = &new_val,
6503 		.maxlen = sizeof(new_val),
6504 		.mode = ctl->mode,
6505 	};
6506 
6507 	if (!rtnl_net_trylock(net))
6508 		return restart_syscall();
6509 
6510 	new_val = *((u32 *)ctl->data);
6511 
6512 	ret = proc_douintvec(&tmp, write, buffer, lenp, ppos);
6513 	if (ret != 0)
6514 		goto out;
6515 
6516 	if (write) {
6517 		if (check_addr_gen_mode(new_val) < 0) {
6518 			ret = -EINVAL;
6519 			goto out;
6520 		}
6521 
6522 		if (idev) {
6523 			if (check_stable_privacy(idev, net, new_val) < 0) {
6524 				ret = -EINVAL;
6525 				goto out;
6526 			}
6527 
6528 			if (idev->cnf.addr_gen_mode != new_val) {
6529 				WRITE_ONCE(idev->cnf.addr_gen_mode, new_val);
6530 				netdev_lock_ops(idev->dev);
6531 				addrconf_init_auto_addrs(idev->dev);
6532 				netdev_unlock_ops(idev->dev);
6533 			}
6534 		} else if (&net->ipv6.devconf_all->addr_gen_mode == ctl->data) {
6535 			struct net_device *dev;
6536 
6537 			WRITE_ONCE(net->ipv6.devconf_dflt->addr_gen_mode, new_val);
6538 			for_each_netdev(net, dev) {
6539 				idev = __in6_dev_get_rtnl_net(dev);
6540 				if (idev &&
6541 				    idev->cnf.addr_gen_mode != new_val) {
6542 					WRITE_ONCE(idev->cnf.addr_gen_mode,
6543 						  new_val);
6544 					netdev_lock_ops(idev->dev);
6545 					addrconf_init_auto_addrs(idev->dev);
6546 					netdev_unlock_ops(idev->dev);
6547 				}
6548 			}
6549 		}
6550 
6551 		WRITE_ONCE(*((u32 *)ctl->data), new_val);
6552 	}
6553 
6554 out:
6555 	rtnl_net_unlock(net);
6556 
6557 	return ret;
6558 }
6559 
addrconf_sysctl_stable_secret(const struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)6560 static int addrconf_sysctl_stable_secret(const struct ctl_table *ctl, int write,
6561 					 void *buffer, size_t *lenp,
6562 					 loff_t *ppos)
6563 {
6564 	int err;
6565 	struct in6_addr addr;
6566 	char str[IPV6_MAX_STRLEN];
6567 	struct ctl_table lctl = *ctl;
6568 	struct net *net = ctl->extra2;
6569 	struct ipv6_stable_secret *secret = ctl->data;
6570 
6571 	if (&net->ipv6.devconf_all->stable_secret == ctl->data)
6572 		return -EIO;
6573 
6574 	lctl.maxlen = IPV6_MAX_STRLEN;
6575 	lctl.data = str;
6576 
6577 	if (!rtnl_net_trylock(net))
6578 		return restart_syscall();
6579 
6580 	if (!write && !secret->initialized) {
6581 		err = -EIO;
6582 		goto out;
6583 	}
6584 
6585 	err = snprintf(str, sizeof(str), "%pI6", &secret->secret);
6586 	if (err >= sizeof(str)) {
6587 		err = -EIO;
6588 		goto out;
6589 	}
6590 
6591 	err = proc_dostring(&lctl, write, buffer, lenp, ppos);
6592 	if (err || !write)
6593 		goto out;
6594 
6595 	if (in6_pton(str, -1, addr.in6_u.u6_addr8, -1, NULL) != 1) {
6596 		err = -EIO;
6597 		goto out;
6598 	}
6599 
6600 	secret->initialized = true;
6601 	secret->secret = addr;
6602 
6603 	if (&net->ipv6.devconf_dflt->stable_secret == ctl->data) {
6604 		struct net_device *dev;
6605 
6606 		for_each_netdev(net, dev) {
6607 			struct inet6_dev *idev = __in6_dev_get_rtnl_net(dev);
6608 
6609 			if (idev) {
6610 				WRITE_ONCE(idev->cnf.addr_gen_mode,
6611 					   IN6_ADDR_GEN_MODE_STABLE_PRIVACY);
6612 			}
6613 		}
6614 	} else {
6615 		struct inet6_dev *idev = ctl->extra1;
6616 
6617 		WRITE_ONCE(idev->cnf.addr_gen_mode,
6618 			   IN6_ADDR_GEN_MODE_STABLE_PRIVACY);
6619 	}
6620 
6621 out:
6622 	rtnl_net_unlock(net);
6623 
6624 	return err;
6625 }
6626 
6627 static
addrconf_sysctl_ignore_routes_with_linkdown(const struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)6628 int addrconf_sysctl_ignore_routes_with_linkdown(const struct ctl_table *ctl,
6629 						int write, void *buffer,
6630 						size_t *lenp,
6631 						loff_t *ppos)
6632 {
6633 	int *valp = ctl->data;
6634 	int val = *valp;
6635 	loff_t pos = *ppos;
6636 	struct ctl_table lctl;
6637 	int ret;
6638 
6639 	/* ctl->data points to idev->cnf.ignore_routes_when_linkdown
6640 	 * we should not modify it until we get the rtnl lock.
6641 	 */
6642 	lctl = *ctl;
6643 	lctl.data = &val;
6644 
6645 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6646 
6647 	if (write)
6648 		ret = addrconf_fixup_linkdown(ctl, valp, val);
6649 	if (ret)
6650 		*ppos = pos;
6651 	return ret;
6652 }
6653 
6654 static
addrconf_set_nopolicy(struct rt6_info * rt,int action)6655 void addrconf_set_nopolicy(struct rt6_info *rt, int action)
6656 {
6657 	if (rt) {
6658 		if (action)
6659 			rt->dst.flags |= DST_NOPOLICY;
6660 		else
6661 			rt->dst.flags &= ~DST_NOPOLICY;
6662 	}
6663 }
6664 
6665 static
addrconf_disable_policy_idev(struct inet6_dev * idev,int val)6666 void addrconf_disable_policy_idev(struct inet6_dev *idev, int val)
6667 {
6668 	struct inet6_ifaddr *ifa;
6669 
6670 	read_lock_bh(&idev->lock);
6671 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
6672 		spin_lock(&ifa->lock);
6673 		if (ifa->rt) {
6674 			/* host routes only use builtin fib6_nh */
6675 			struct fib6_nh *nh = ifa->rt->fib6_nh;
6676 			int cpu;
6677 
6678 			rcu_read_lock();
6679 			ifa->rt->dst_nopolicy = val ? true : false;
6680 			if (nh->rt6i_pcpu) {
6681 				for_each_possible_cpu(cpu) {
6682 					struct rt6_info **rtp;
6683 
6684 					rtp = per_cpu_ptr(nh->rt6i_pcpu, cpu);
6685 					addrconf_set_nopolicy(*rtp, val);
6686 				}
6687 			}
6688 			rcu_read_unlock();
6689 		}
6690 		spin_unlock(&ifa->lock);
6691 	}
6692 	read_unlock_bh(&idev->lock);
6693 }
6694 
6695 static
addrconf_disable_policy(const struct ctl_table * ctl,int * valp,int val)6696 int addrconf_disable_policy(const struct ctl_table *ctl, int *valp, int val)
6697 {
6698 	struct net *net = (struct net *)ctl->extra2;
6699 	struct inet6_dev *idev;
6700 
6701 	if (valp == &net->ipv6.devconf_dflt->disable_policy) {
6702 		WRITE_ONCE(*valp, val);
6703 		return 0;
6704 	}
6705 
6706 	if (!rtnl_net_trylock(net))
6707 		return restart_syscall();
6708 
6709 	WRITE_ONCE(*valp, val);
6710 
6711 	if (valp == &net->ipv6.devconf_all->disable_policy)  {
6712 		struct net_device *dev;
6713 
6714 		for_each_netdev(net, dev) {
6715 			idev = __in6_dev_get_rtnl_net(dev);
6716 			if (idev)
6717 				addrconf_disable_policy_idev(idev, val);
6718 		}
6719 	} else {
6720 		idev = (struct inet6_dev *)ctl->extra1;
6721 		addrconf_disable_policy_idev(idev, val);
6722 	}
6723 
6724 	rtnl_net_unlock(net);
6725 	return 0;
6726 }
6727 
addrconf_sysctl_disable_policy(const struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)6728 static int addrconf_sysctl_disable_policy(const struct ctl_table *ctl, int write,
6729 				   void *buffer, size_t *lenp, loff_t *ppos)
6730 {
6731 	int *valp = ctl->data;
6732 	int val = *valp;
6733 	loff_t pos = *ppos;
6734 	struct ctl_table lctl;
6735 	int ret;
6736 
6737 	lctl = *ctl;
6738 	lctl.data = &val;
6739 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6740 
6741 	if (write && (*valp != val))
6742 		ret = addrconf_disable_policy(ctl, valp, val);
6743 
6744 	if (ret)
6745 		*ppos = pos;
6746 
6747 	return ret;
6748 }
6749 
6750 static int minus_one = -1;
6751 static const int two_five_five = 255;
6752 static u32 ioam6_if_id_max = U16_MAX;
6753 
6754 static const struct ctl_table addrconf_sysctl[] = {
6755 	{
6756 		.procname	= "forwarding",
6757 		.data		= &ipv6_devconf.forwarding,
6758 		.maxlen		= sizeof(int),
6759 		.mode		= 0644,
6760 		.proc_handler	= addrconf_sysctl_forward,
6761 	},
6762 	{
6763 		.procname	= "hop_limit",
6764 		.data		= &ipv6_devconf.hop_limit,
6765 		.maxlen		= sizeof(int),
6766 		.mode		= 0644,
6767 		.proc_handler	= proc_dointvec_minmax,
6768 		.extra1		= (void *)SYSCTL_ONE,
6769 		.extra2		= (void *)&two_five_five,
6770 	},
6771 	{
6772 		.procname	= "mtu",
6773 		.data		= &ipv6_devconf.mtu6,
6774 		.maxlen		= sizeof(int),
6775 		.mode		= 0644,
6776 		.proc_handler	= addrconf_sysctl_mtu,
6777 	},
6778 	{
6779 		.procname	= "accept_ra",
6780 		.data		= &ipv6_devconf.accept_ra,
6781 		.maxlen		= sizeof(int),
6782 		.mode		= 0644,
6783 		.proc_handler	= proc_dointvec,
6784 	},
6785 	{
6786 		.procname	= "accept_redirects",
6787 		.data		= &ipv6_devconf.accept_redirects,
6788 		.maxlen		= sizeof(int),
6789 		.mode		= 0644,
6790 		.proc_handler	= proc_dointvec,
6791 	},
6792 	{
6793 		.procname	= "autoconf",
6794 		.data		= &ipv6_devconf.autoconf,
6795 		.maxlen		= sizeof(int),
6796 		.mode		= 0644,
6797 		.proc_handler	= proc_dointvec,
6798 	},
6799 	{
6800 		.procname	= "dad_transmits",
6801 		.data		= &ipv6_devconf.dad_transmits,
6802 		.maxlen		= sizeof(int),
6803 		.mode		= 0644,
6804 		.proc_handler	= proc_dointvec,
6805 	},
6806 	{
6807 		.procname	= "router_solicitations",
6808 		.data		= &ipv6_devconf.rtr_solicits,
6809 		.maxlen		= sizeof(int),
6810 		.mode		= 0644,
6811 		.proc_handler	= proc_dointvec_minmax,
6812 		.extra1		= &minus_one,
6813 	},
6814 	{
6815 		.procname	= "router_solicitation_interval",
6816 		.data		= &ipv6_devconf.rtr_solicit_interval,
6817 		.maxlen		= sizeof(int),
6818 		.mode		= 0644,
6819 		.proc_handler	= proc_dointvec_jiffies,
6820 	},
6821 	{
6822 		.procname	= "router_solicitation_max_interval",
6823 		.data		= &ipv6_devconf.rtr_solicit_max_interval,
6824 		.maxlen		= sizeof(int),
6825 		.mode		= 0644,
6826 		.proc_handler	= proc_dointvec_jiffies,
6827 	},
6828 	{
6829 		.procname	= "router_solicitation_delay",
6830 		.data		= &ipv6_devconf.rtr_solicit_delay,
6831 		.maxlen		= sizeof(int),
6832 		.mode		= 0644,
6833 		.proc_handler	= proc_dointvec_jiffies,
6834 	},
6835 	{
6836 		.procname	= "force_mld_version",
6837 		.data		= &ipv6_devconf.force_mld_version,
6838 		.maxlen		= sizeof(int),
6839 		.mode		= 0644,
6840 		.proc_handler	= proc_dointvec,
6841 	},
6842 	{
6843 		.procname	= "mldv1_unsolicited_report_interval",
6844 		.data		=
6845 			&ipv6_devconf.mldv1_unsolicited_report_interval,
6846 		.maxlen		= sizeof(int),
6847 		.mode		= 0644,
6848 		.proc_handler	= proc_dointvec_ms_jiffies,
6849 	},
6850 	{
6851 		.procname	= "mldv2_unsolicited_report_interval",
6852 		.data		=
6853 			&ipv6_devconf.mldv2_unsolicited_report_interval,
6854 		.maxlen		= sizeof(int),
6855 		.mode		= 0644,
6856 		.proc_handler	= proc_dointvec_ms_jiffies,
6857 	},
6858 	{
6859 		.procname	= "use_tempaddr",
6860 		.data		= &ipv6_devconf.use_tempaddr,
6861 		.maxlen		= sizeof(int),
6862 		.mode		= 0644,
6863 		.proc_handler	= proc_dointvec,
6864 	},
6865 	{
6866 		.procname	= "temp_valid_lft",
6867 		.data		= &ipv6_devconf.temp_valid_lft,
6868 		.maxlen		= sizeof(int),
6869 		.mode		= 0644,
6870 		.proc_handler	= proc_dointvec,
6871 	},
6872 	{
6873 		.procname	= "temp_prefered_lft",
6874 		.data		= &ipv6_devconf.temp_prefered_lft,
6875 		.maxlen		= sizeof(int),
6876 		.mode		= 0644,
6877 		.proc_handler	= proc_dointvec,
6878 	},
6879 	{
6880 		.procname       = "regen_min_advance",
6881 		.data           = &ipv6_devconf.regen_min_advance,
6882 		.maxlen         = sizeof(int),
6883 		.mode           = 0644,
6884 		.proc_handler   = proc_dointvec,
6885 	},
6886 	{
6887 		.procname	= "regen_max_retry",
6888 		.data		= &ipv6_devconf.regen_max_retry,
6889 		.maxlen		= sizeof(int),
6890 		.mode		= 0644,
6891 		.proc_handler	= proc_dointvec,
6892 	},
6893 	{
6894 		.procname	= "max_desync_factor",
6895 		.data		= &ipv6_devconf.max_desync_factor,
6896 		.maxlen		= sizeof(int),
6897 		.mode		= 0644,
6898 		.proc_handler	= proc_dointvec,
6899 	},
6900 	{
6901 		.procname	= "max_addresses",
6902 		.data		= &ipv6_devconf.max_addresses,
6903 		.maxlen		= sizeof(int),
6904 		.mode		= 0644,
6905 		.proc_handler	= proc_dointvec,
6906 	},
6907 	{
6908 		.procname	= "accept_ra_defrtr",
6909 		.data		= &ipv6_devconf.accept_ra_defrtr,
6910 		.maxlen		= sizeof(int),
6911 		.mode		= 0644,
6912 		.proc_handler	= proc_dointvec,
6913 	},
6914 	{
6915 		.procname	= "ra_defrtr_metric",
6916 		.data		= &ipv6_devconf.ra_defrtr_metric,
6917 		.maxlen		= sizeof(u32),
6918 		.mode		= 0644,
6919 		.proc_handler	= proc_douintvec_minmax,
6920 		.extra1		= (void *)SYSCTL_ONE,
6921 	},
6922 	{
6923 		.procname	= "accept_ra_min_hop_limit",
6924 		.data		= &ipv6_devconf.accept_ra_min_hop_limit,
6925 		.maxlen		= sizeof(int),
6926 		.mode		= 0644,
6927 		.proc_handler	= proc_dointvec,
6928 	},
6929 	{
6930 		.procname	= "accept_ra_min_lft",
6931 		.data		= &ipv6_devconf.accept_ra_min_lft,
6932 		.maxlen		= sizeof(int),
6933 		.mode		= 0644,
6934 		.proc_handler	= proc_dointvec,
6935 	},
6936 	{
6937 		.procname	= "accept_ra_pinfo",
6938 		.data		= &ipv6_devconf.accept_ra_pinfo,
6939 		.maxlen		= sizeof(int),
6940 		.mode		= 0644,
6941 		.proc_handler	= proc_dointvec,
6942 	},
6943 	{
6944 		.procname	= "ra_honor_pio_life",
6945 		.data		= &ipv6_devconf.ra_honor_pio_life,
6946 		.maxlen		= sizeof(u8),
6947 		.mode		= 0644,
6948 		.proc_handler	= proc_dou8vec_minmax,
6949 		.extra1		= SYSCTL_ZERO,
6950 		.extra2		= SYSCTL_ONE,
6951 	},
6952 	{
6953 		.procname	= "ra_honor_pio_pflag",
6954 		.data		= &ipv6_devconf.ra_honor_pio_pflag,
6955 		.maxlen		= sizeof(u8),
6956 		.mode		= 0644,
6957 		.proc_handler	= proc_dou8vec_minmax,
6958 		.extra1		= SYSCTL_ZERO,
6959 		.extra2		= SYSCTL_ONE,
6960 	},
6961 #ifdef CONFIG_IPV6_ROUTER_PREF
6962 	{
6963 		.procname	= "accept_ra_rtr_pref",
6964 		.data		= &ipv6_devconf.accept_ra_rtr_pref,
6965 		.maxlen		= sizeof(int),
6966 		.mode		= 0644,
6967 		.proc_handler	= proc_dointvec,
6968 	},
6969 	{
6970 		.procname	= "router_probe_interval",
6971 		.data		= &ipv6_devconf.rtr_probe_interval,
6972 		.maxlen		= sizeof(int),
6973 		.mode		= 0644,
6974 		.proc_handler	= proc_dointvec_jiffies,
6975 	},
6976 #ifdef CONFIG_IPV6_ROUTE_INFO
6977 	{
6978 		.procname	= "accept_ra_rt_info_min_plen",
6979 		.data		= &ipv6_devconf.accept_ra_rt_info_min_plen,
6980 		.maxlen		= sizeof(int),
6981 		.mode		= 0644,
6982 		.proc_handler	= proc_dointvec,
6983 	},
6984 	{
6985 		.procname	= "accept_ra_rt_info_max_plen",
6986 		.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
6987 		.maxlen		= sizeof(int),
6988 		.mode		= 0644,
6989 		.proc_handler	= proc_dointvec,
6990 	},
6991 #endif
6992 #endif
6993 	{
6994 		.procname	= "proxy_ndp",
6995 		.data		= &ipv6_devconf.proxy_ndp,
6996 		.maxlen		= sizeof(int),
6997 		.mode		= 0644,
6998 		.proc_handler	= addrconf_sysctl_proxy_ndp,
6999 	},
7000 	{
7001 		.procname	= "accept_source_route",
7002 		.data		= &ipv6_devconf.accept_source_route,
7003 		.maxlen		= sizeof(int),
7004 		.mode		= 0644,
7005 		.proc_handler	= proc_dointvec,
7006 	},
7007 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
7008 	{
7009 		.procname	= "optimistic_dad",
7010 		.data		= &ipv6_devconf.optimistic_dad,
7011 		.maxlen		= sizeof(int),
7012 		.mode		= 0644,
7013 		.proc_handler   = proc_dointvec,
7014 	},
7015 	{
7016 		.procname	= "use_optimistic",
7017 		.data		= &ipv6_devconf.use_optimistic,
7018 		.maxlen		= sizeof(int),
7019 		.mode		= 0644,
7020 		.proc_handler	= proc_dointvec,
7021 	},
7022 #endif
7023 #ifdef CONFIG_IPV6_MROUTE
7024 	{
7025 		.procname	= "mc_forwarding",
7026 		.data		= &ipv6_devconf.mc_forwarding,
7027 		.maxlen		= sizeof(int),
7028 		.mode		= 0444,
7029 		.proc_handler	= proc_dointvec,
7030 	},
7031 #endif
7032 	{
7033 		.procname	= "disable_ipv6",
7034 		.data		= &ipv6_devconf.disable_ipv6,
7035 		.maxlen		= sizeof(int),
7036 		.mode		= 0644,
7037 		.proc_handler	= addrconf_sysctl_disable,
7038 	},
7039 	{
7040 		.procname	= "accept_dad",
7041 		.data		= &ipv6_devconf.accept_dad,
7042 		.maxlen		= sizeof(int),
7043 		.mode		= 0644,
7044 		.proc_handler	= proc_dointvec,
7045 	},
7046 	{
7047 		.procname	= "force_tllao",
7048 		.data		= &ipv6_devconf.force_tllao,
7049 		.maxlen		= sizeof(int),
7050 		.mode		= 0644,
7051 		.proc_handler	= proc_dointvec
7052 	},
7053 	{
7054 		.procname	= "ndisc_notify",
7055 		.data		= &ipv6_devconf.ndisc_notify,
7056 		.maxlen		= sizeof(int),
7057 		.mode		= 0644,
7058 		.proc_handler	= proc_dointvec
7059 	},
7060 	{
7061 		.procname	= "suppress_frag_ndisc",
7062 		.data		= &ipv6_devconf.suppress_frag_ndisc,
7063 		.maxlen		= sizeof(int),
7064 		.mode		= 0644,
7065 		.proc_handler	= proc_dointvec
7066 	},
7067 	{
7068 		.procname	= "accept_ra_from_local",
7069 		.data		= &ipv6_devconf.accept_ra_from_local,
7070 		.maxlen		= sizeof(int),
7071 		.mode		= 0644,
7072 		.proc_handler	= proc_dointvec,
7073 	},
7074 	{
7075 		.procname	= "accept_ra_mtu",
7076 		.data		= &ipv6_devconf.accept_ra_mtu,
7077 		.maxlen		= sizeof(int),
7078 		.mode		= 0644,
7079 		.proc_handler	= proc_dointvec,
7080 	},
7081 	{
7082 		.procname	= "stable_secret",
7083 		.data		= &ipv6_devconf.stable_secret,
7084 		.maxlen		= IPV6_MAX_STRLEN,
7085 		.mode		= 0600,
7086 		.proc_handler	= addrconf_sysctl_stable_secret,
7087 	},
7088 	{
7089 		.procname	= "use_oif_addrs_only",
7090 		.data		= &ipv6_devconf.use_oif_addrs_only,
7091 		.maxlen		= sizeof(int),
7092 		.mode		= 0644,
7093 		.proc_handler	= proc_dointvec,
7094 	},
7095 	{
7096 		.procname	= "ignore_routes_with_linkdown",
7097 		.data		= &ipv6_devconf.ignore_routes_with_linkdown,
7098 		.maxlen		= sizeof(int),
7099 		.mode		= 0644,
7100 		.proc_handler	= addrconf_sysctl_ignore_routes_with_linkdown,
7101 	},
7102 	{
7103 		.procname	= "drop_unicast_in_l2_multicast",
7104 		.data		= &ipv6_devconf.drop_unicast_in_l2_multicast,
7105 		.maxlen		= sizeof(int),
7106 		.mode		= 0644,
7107 		.proc_handler	= proc_dointvec,
7108 	},
7109 	{
7110 		.procname	= "drop_unsolicited_na",
7111 		.data		= &ipv6_devconf.drop_unsolicited_na,
7112 		.maxlen		= sizeof(int),
7113 		.mode		= 0644,
7114 		.proc_handler	= proc_dointvec,
7115 	},
7116 	{
7117 		.procname	= "keep_addr_on_down",
7118 		.data		= &ipv6_devconf.keep_addr_on_down,
7119 		.maxlen		= sizeof(int),
7120 		.mode		= 0644,
7121 		.proc_handler	= proc_dointvec,
7122 
7123 	},
7124 	{
7125 		.procname	= "seg6_enabled",
7126 		.data		= &ipv6_devconf.seg6_enabled,
7127 		.maxlen		= sizeof(int),
7128 		.mode		= 0644,
7129 		.proc_handler	= proc_dointvec,
7130 	},
7131 #ifdef CONFIG_IPV6_SEG6_HMAC
7132 	{
7133 		.procname	= "seg6_require_hmac",
7134 		.data		= &ipv6_devconf.seg6_require_hmac,
7135 		.maxlen		= sizeof(int),
7136 		.mode		= 0644,
7137 		.proc_handler	= proc_dointvec,
7138 	},
7139 #endif
7140 	{
7141 		.procname       = "enhanced_dad",
7142 		.data           = &ipv6_devconf.enhanced_dad,
7143 		.maxlen         = sizeof(int),
7144 		.mode           = 0644,
7145 		.proc_handler   = proc_dointvec,
7146 	},
7147 	{
7148 		.procname	= "addr_gen_mode",
7149 		.data		= &ipv6_devconf.addr_gen_mode,
7150 		.maxlen		= sizeof(int),
7151 		.mode		= 0644,
7152 		.proc_handler	= addrconf_sysctl_addr_gen_mode,
7153 	},
7154 	{
7155 		.procname       = "disable_policy",
7156 		.data           = &ipv6_devconf.disable_policy,
7157 		.maxlen         = sizeof(int),
7158 		.mode           = 0644,
7159 		.proc_handler   = addrconf_sysctl_disable_policy,
7160 	},
7161 	{
7162 		.procname	= "ndisc_tclass",
7163 		.data		= &ipv6_devconf.ndisc_tclass,
7164 		.maxlen		= sizeof(int),
7165 		.mode		= 0644,
7166 		.proc_handler	= proc_dointvec_minmax,
7167 		.extra1		= (void *)SYSCTL_ZERO,
7168 		.extra2		= (void *)&two_five_five,
7169 	},
7170 	{
7171 		.procname	= "rpl_seg_enabled",
7172 		.data		= &ipv6_devconf.rpl_seg_enabled,
7173 		.maxlen		= sizeof(int),
7174 		.mode		= 0644,
7175 		.proc_handler	= proc_dointvec,
7176 	},
7177 	{
7178 		.procname	= "ioam6_enabled",
7179 		.data		= &ipv6_devconf.ioam6_enabled,
7180 		.maxlen		= sizeof(u8),
7181 		.mode		= 0644,
7182 		.proc_handler	= proc_dou8vec_minmax,
7183 		.extra1		= (void *)SYSCTL_ZERO,
7184 		.extra2		= (void *)SYSCTL_ONE,
7185 	},
7186 	{
7187 		.procname	= "ioam6_id",
7188 		.data		= &ipv6_devconf.ioam6_id,
7189 		.maxlen		= sizeof(u32),
7190 		.mode		= 0644,
7191 		.proc_handler	= proc_douintvec_minmax,
7192 		.extra1		= (void *)SYSCTL_ZERO,
7193 		.extra2		= (void *)&ioam6_if_id_max,
7194 	},
7195 	{
7196 		.procname	= "ioam6_id_wide",
7197 		.data		= &ipv6_devconf.ioam6_id_wide,
7198 		.maxlen		= sizeof(u32),
7199 		.mode		= 0644,
7200 		.proc_handler	= proc_douintvec,
7201 	},
7202 	{
7203 		.procname	= "ndisc_evict_nocarrier",
7204 		.data		= &ipv6_devconf.ndisc_evict_nocarrier,
7205 		.maxlen		= sizeof(u8),
7206 		.mode		= 0644,
7207 		.proc_handler	= proc_dou8vec_minmax,
7208 		.extra1		= (void *)SYSCTL_ZERO,
7209 		.extra2		= (void *)SYSCTL_ONE,
7210 	},
7211 	{
7212 		.procname	= "accept_untracked_na",
7213 		.data		= &ipv6_devconf.accept_untracked_na,
7214 		.maxlen		= sizeof(int),
7215 		.mode		= 0644,
7216 		.proc_handler	= proc_dointvec_minmax,
7217 		.extra1		= SYSCTL_ZERO,
7218 		.extra2		= SYSCTL_TWO,
7219 	},
7220 };
7221 
__addrconf_sysctl_register(struct net * net,char * dev_name,struct inet6_dev * idev,struct ipv6_devconf * p)7222 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
7223 		struct inet6_dev *idev, struct ipv6_devconf *p)
7224 {
7225 	size_t table_size = ARRAY_SIZE(addrconf_sysctl);
7226 	int i, ifindex;
7227 	struct ctl_table *table;
7228 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
7229 
7230 	table = kmemdup(addrconf_sysctl, sizeof(addrconf_sysctl), GFP_KERNEL_ACCOUNT);
7231 	if (!table)
7232 		goto out;
7233 
7234 	for (i = 0; i < table_size; i++) {
7235 		table[i].data += (char *)p - (char *)&ipv6_devconf;
7236 		/* If one of these is already set, then it is not safe to
7237 		 * overwrite either of them: this makes proc_dointvec_minmax
7238 		 * usable.
7239 		 */
7240 		if (!table[i].extra1 && !table[i].extra2) {
7241 			table[i].extra1 = idev; /* embedded; no ref */
7242 			table[i].extra2 = net;
7243 		}
7244 	}
7245 
7246 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
7247 
7248 	p->sysctl_header = register_net_sysctl_sz(net, path, table,
7249 						  table_size);
7250 	if (!p->sysctl_header)
7251 		goto free;
7252 
7253 	if (!strcmp(dev_name, "all"))
7254 		ifindex = NETCONFA_IFINDEX_ALL;
7255 	else if (!strcmp(dev_name, "default"))
7256 		ifindex = NETCONFA_IFINDEX_DEFAULT;
7257 	else
7258 		ifindex = idev->dev->ifindex;
7259 	inet6_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL,
7260 				     ifindex, p);
7261 	return 0;
7262 
7263 free:
7264 	kfree(table);
7265 out:
7266 	return -ENOBUFS;
7267 }
7268 
__addrconf_sysctl_unregister(struct net * net,struct ipv6_devconf * p,int ifindex)7269 static void __addrconf_sysctl_unregister(struct net *net,
7270 					 struct ipv6_devconf *p, int ifindex)
7271 {
7272 	const struct ctl_table *table;
7273 
7274 	if (!p->sysctl_header)
7275 		return;
7276 
7277 	table = p->sysctl_header->ctl_table_arg;
7278 	unregister_net_sysctl_table(p->sysctl_header);
7279 	p->sysctl_header = NULL;
7280 	kfree(table);
7281 
7282 	inet6_netconf_notify_devconf(net, RTM_DELNETCONF, 0, ifindex, NULL);
7283 }
7284 
addrconf_sysctl_register(struct inet6_dev * idev)7285 static int addrconf_sysctl_register(struct inet6_dev *idev)
7286 {
7287 	int err;
7288 
7289 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
7290 		return -EINVAL;
7291 
7292 	err = neigh_sysctl_register(idev->dev, idev->nd_parms,
7293 				    &ndisc_ifinfo_sysctl_change);
7294 	if (err)
7295 		return err;
7296 	err = __addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
7297 					 idev, &idev->cnf);
7298 	if (err)
7299 		neigh_sysctl_unregister(idev->nd_parms);
7300 
7301 	return err;
7302 }
7303 
addrconf_sysctl_unregister(struct inet6_dev * idev)7304 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
7305 {
7306 	__addrconf_sysctl_unregister(dev_net(idev->dev), &idev->cnf,
7307 				     idev->dev->ifindex);
7308 	neigh_sysctl_unregister(idev->nd_parms);
7309 }
7310 
7311 
7312 #endif
7313 
addrconf_init_net(struct net * net)7314 static int __net_init addrconf_init_net(struct net *net)
7315 {
7316 	int err = -ENOMEM;
7317 	struct ipv6_devconf *all, *dflt;
7318 
7319 	spin_lock_init(&net->ipv6.addrconf_hash_lock);
7320 	INIT_DEFERRABLE_WORK(&net->ipv6.addr_chk_work, addrconf_verify_work);
7321 	net->ipv6.inet6_addr_lst = kcalloc(IN6_ADDR_HSIZE,
7322 					   sizeof(struct hlist_head),
7323 					   GFP_KERNEL);
7324 	if (!net->ipv6.inet6_addr_lst)
7325 		goto err_alloc_addr;
7326 
7327 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
7328 	if (!all)
7329 		goto err_alloc_all;
7330 
7331 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
7332 	if (!dflt)
7333 		goto err_alloc_dflt;
7334 
7335 	if (!net_eq(net, &init_net)) {
7336 		switch (net_inherit_devconf()) {
7337 		case 1:  /* copy from init_net */
7338 			memcpy(all, init_net.ipv6.devconf_all,
7339 			       sizeof(ipv6_devconf));
7340 			memcpy(dflt, init_net.ipv6.devconf_dflt,
7341 			       sizeof(ipv6_devconf_dflt));
7342 			break;
7343 		case 3: /* copy from the current netns */
7344 			memcpy(all, current->nsproxy->net_ns->ipv6.devconf_all,
7345 			       sizeof(ipv6_devconf));
7346 			memcpy(dflt,
7347 			       current->nsproxy->net_ns->ipv6.devconf_dflt,
7348 			       sizeof(ipv6_devconf_dflt));
7349 			break;
7350 		case 0:
7351 		case 2:
7352 			/* use compiled values */
7353 			break;
7354 		}
7355 	}
7356 
7357 	/* these will be inherited by all namespaces */
7358 	dflt->autoconf = ipv6_defaults.autoconf;
7359 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
7360 
7361 	dflt->stable_secret.initialized = false;
7362 	all->stable_secret.initialized = false;
7363 
7364 	net->ipv6.devconf_all = all;
7365 	net->ipv6.devconf_dflt = dflt;
7366 
7367 #ifdef CONFIG_SYSCTL
7368 	err = __addrconf_sysctl_register(net, "all", NULL, all);
7369 	if (err < 0)
7370 		goto err_reg_all;
7371 
7372 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
7373 	if (err < 0)
7374 		goto err_reg_dflt;
7375 #endif
7376 	return 0;
7377 
7378 #ifdef CONFIG_SYSCTL
7379 err_reg_dflt:
7380 	__addrconf_sysctl_unregister(net, all, NETCONFA_IFINDEX_ALL);
7381 err_reg_all:
7382 	kfree(dflt);
7383 	net->ipv6.devconf_dflt = NULL;
7384 #endif
7385 err_alloc_dflt:
7386 	kfree(all);
7387 	net->ipv6.devconf_all = NULL;
7388 err_alloc_all:
7389 	kfree(net->ipv6.inet6_addr_lst);
7390 err_alloc_addr:
7391 	return err;
7392 }
7393 
addrconf_exit_net(struct net * net)7394 static void __net_exit addrconf_exit_net(struct net *net)
7395 {
7396 	int i;
7397 
7398 #ifdef CONFIG_SYSCTL
7399 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_dflt,
7400 				     NETCONFA_IFINDEX_DEFAULT);
7401 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_all,
7402 				     NETCONFA_IFINDEX_ALL);
7403 #endif
7404 	kfree(net->ipv6.devconf_dflt);
7405 	net->ipv6.devconf_dflt = NULL;
7406 	kfree(net->ipv6.devconf_all);
7407 	net->ipv6.devconf_all = NULL;
7408 
7409 	cancel_delayed_work_sync(&net->ipv6.addr_chk_work);
7410 	/*
7411 	 *	Check hash table, then free it.
7412 	 */
7413 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
7414 		WARN_ON_ONCE(!hlist_empty(&net->ipv6.inet6_addr_lst[i]));
7415 
7416 	kfree(net->ipv6.inet6_addr_lst);
7417 	net->ipv6.inet6_addr_lst = NULL;
7418 }
7419 
7420 static struct pernet_operations addrconf_ops = {
7421 	.init = addrconf_init_net,
7422 	.exit = addrconf_exit_net,
7423 };
7424 
7425 static struct rtnl_af_ops inet6_ops __read_mostly = {
7426 	.family		  = AF_INET6,
7427 	.fill_link_af	  = inet6_fill_link_af,
7428 	.get_link_af_size = inet6_get_link_af_size,
7429 	.validate_link_af = inet6_validate_link_af,
7430 	.set_link_af	  = inet6_set_link_af,
7431 };
7432 
7433 static const struct rtnl_msg_handler addrconf_rtnl_msg_handlers[] __initconst_or_module = {
7434 	{.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_GETLINK,
7435 	 .dumpit = inet6_dump_ifinfo, .flags = RTNL_FLAG_DUMP_UNLOCKED},
7436 	{.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_NEWADDR,
7437 	 .doit = inet6_rtm_newaddr, .flags = RTNL_FLAG_DOIT_PERNET},
7438 	{.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_DELADDR,
7439 	 .doit = inet6_rtm_deladdr, .flags = RTNL_FLAG_DOIT_PERNET},
7440 	{.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_GETADDR,
7441 	 .doit = inet6_rtm_getaddr, .dumpit = inet6_dump_ifaddr,
7442 	 .flags = RTNL_FLAG_DOIT_UNLOCKED | RTNL_FLAG_DUMP_UNLOCKED},
7443 	{.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_GETMULTICAST,
7444 	 .dumpit = inet6_dump_ifmcaddr,
7445 	 .flags = RTNL_FLAG_DUMP_UNLOCKED},
7446 	{.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_GETANYCAST,
7447 	 .dumpit = inet6_dump_ifacaddr,
7448 	 .flags = RTNL_FLAG_DUMP_UNLOCKED},
7449 	{.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_GETNETCONF,
7450 	 .doit = inet6_netconf_get_devconf, .dumpit = inet6_netconf_dump_devconf,
7451 	 .flags = RTNL_FLAG_DOIT_UNLOCKED | RTNL_FLAG_DUMP_UNLOCKED},
7452 };
7453 
7454 /*
7455  *	Init / cleanup code
7456  */
7457 
addrconf_init(void)7458 int __init addrconf_init(void)
7459 {
7460 	struct inet6_dev *idev;
7461 	int err;
7462 
7463 	err = ipv6_addr_label_init();
7464 	if (err < 0) {
7465 		pr_crit("%s: cannot initialize default policy table: %d\n",
7466 			__func__, err);
7467 		goto out;
7468 	}
7469 
7470 	err = register_pernet_subsys(&addrconf_ops);
7471 	if (err < 0)
7472 		goto out_addrlabel;
7473 
7474 	/* All works using addrconf_wq need to lock rtnl. */
7475 	addrconf_wq = create_singlethread_workqueue("ipv6_addrconf");
7476 	if (!addrconf_wq) {
7477 		err = -ENOMEM;
7478 		goto out_nowq;
7479 	}
7480 
7481 	rtnl_net_lock(&init_net);
7482 	idev = ipv6_add_dev(blackhole_netdev);
7483 	rtnl_net_unlock(&init_net);
7484 	if (IS_ERR(idev)) {
7485 		err = PTR_ERR(idev);
7486 		goto errlo;
7487 	}
7488 
7489 	ip6_route_init_special_entries();
7490 
7491 	register_netdevice_notifier(&ipv6_dev_notf);
7492 
7493 	addrconf_verify(&init_net);
7494 
7495 	err = rtnl_af_register(&inet6_ops);
7496 	if (err)
7497 		goto erraf;
7498 
7499 	err = rtnl_register_many(addrconf_rtnl_msg_handlers);
7500 	if (err)
7501 		goto errout;
7502 
7503 	err = ipv6_addr_label_rtnl_register();
7504 	if (err < 0)
7505 		goto errout;
7506 
7507 	return 0;
7508 errout:
7509 	rtnl_unregister_all(PF_INET6);
7510 	rtnl_af_unregister(&inet6_ops);
7511 erraf:
7512 	unregister_netdevice_notifier(&ipv6_dev_notf);
7513 errlo:
7514 	destroy_workqueue(addrconf_wq);
7515 out_nowq:
7516 	unregister_pernet_subsys(&addrconf_ops);
7517 out_addrlabel:
7518 	ipv6_addr_label_cleanup();
7519 out:
7520 	return err;
7521 }
7522 
addrconf_cleanup(void)7523 void addrconf_cleanup(void)
7524 {
7525 	struct net_device *dev;
7526 
7527 	unregister_netdevice_notifier(&ipv6_dev_notf);
7528 	unregister_pernet_subsys(&addrconf_ops);
7529 	ipv6_addr_label_cleanup();
7530 
7531 	rtnl_af_unregister(&inet6_ops);
7532 
7533 	rtnl_net_lock(&init_net);
7534 
7535 	/* clean dev list */
7536 	for_each_netdev(&init_net, dev) {
7537 		if (!__in6_dev_get_rtnl_net(dev))
7538 			continue;
7539 		addrconf_ifdown(dev, true);
7540 	}
7541 	addrconf_ifdown(init_net.loopback_dev, true);
7542 
7543 	rtnl_net_unlock(&init_net);
7544 
7545 	destroy_workqueue(addrconf_wq);
7546 }
7547