xref: /linux/net/ipv6/addrconf.c (revision 8be4d31cb8aaeea27bde4b7ddb26e28a89062ebf)
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 	.force_forwarding	= 0,
243 };
244 
245 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
246 	.forwarding		= 0,
247 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
248 	.mtu6			= IPV6_MIN_MTU,
249 	.accept_ra		= 1,
250 	.accept_redirects	= 1,
251 	.autoconf		= 1,
252 	.force_mld_version	= 0,
253 	.mldv1_unsolicited_report_interval = 10 * HZ,
254 	.mldv2_unsolicited_report_interval = HZ,
255 	.dad_transmits		= 1,
256 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
257 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
258 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
259 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
260 	.use_tempaddr		= 0,
261 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
262 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
263 	.regen_min_advance	= REGEN_MIN_ADVANCE,
264 	.regen_max_retry	= REGEN_MAX_RETRY,
265 	.max_desync_factor	= MAX_DESYNC_FACTOR,
266 	.max_addresses		= IPV6_MAX_ADDRESSES,
267 	.accept_ra_defrtr	= 1,
268 	.ra_defrtr_metric	= IP6_RT_PRIO_USER,
269 	.accept_ra_from_local	= 0,
270 	.accept_ra_min_hop_limit= 1,
271 	.accept_ra_min_lft	= 0,
272 	.accept_ra_pinfo	= 1,
273 #ifdef CONFIG_IPV6_ROUTER_PREF
274 	.accept_ra_rtr_pref	= 1,
275 	.rtr_probe_interval	= 60 * HZ,
276 #ifdef CONFIG_IPV6_ROUTE_INFO
277 	.accept_ra_rt_info_min_plen = 0,
278 	.accept_ra_rt_info_max_plen = 0,
279 #endif
280 #endif
281 	.proxy_ndp		= 0,
282 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
283 	.disable_ipv6		= 0,
284 	.accept_dad		= 1,
285 	.suppress_frag_ndisc	= 1,
286 	.accept_ra_mtu		= 1,
287 	.stable_secret		= {
288 		.initialized = false,
289 	},
290 	.use_oif_addrs_only	= 0,
291 	.ignore_routes_with_linkdown = 0,
292 	.keep_addr_on_down	= 0,
293 	.seg6_enabled		= 0,
294 #ifdef CONFIG_IPV6_SEG6_HMAC
295 	.seg6_require_hmac	= 0,
296 #endif
297 	.enhanced_dad           = 1,
298 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
299 	.disable_policy		= 0,
300 	.rpl_seg_enabled	= 0,
301 	.ioam6_enabled		= 0,
302 	.ioam6_id               = IOAM6_DEFAULT_IF_ID,
303 	.ioam6_id_wide		= IOAM6_DEFAULT_IF_ID_WIDE,
304 	.ndisc_evict_nocarrier	= 1,
305 	.ra_honor_pio_life	= 0,
306 	.ra_honor_pio_pflag	= 0,
307 	.force_forwarding	= 0,
308 };
309 
310 /* Check if link is ready: is it up and is a valid qdisc available */
addrconf_link_ready(const struct net_device * dev)311 static inline bool addrconf_link_ready(const struct net_device *dev)
312 {
313 	return netif_oper_up(dev) && !qdisc_tx_is_noop(dev);
314 }
315 
addrconf_del_rs_timer(struct inet6_dev * idev)316 static void addrconf_del_rs_timer(struct inet6_dev *idev)
317 {
318 	if (timer_delete(&idev->rs_timer))
319 		__in6_dev_put(idev);
320 }
321 
addrconf_del_dad_work(struct inet6_ifaddr * ifp)322 static void addrconf_del_dad_work(struct inet6_ifaddr *ifp)
323 {
324 	if (cancel_delayed_work(&ifp->dad_work))
325 		__in6_ifa_put(ifp);
326 }
327 
addrconf_mod_rs_timer(struct inet6_dev * idev,unsigned long when)328 static void addrconf_mod_rs_timer(struct inet6_dev *idev,
329 				  unsigned long when)
330 {
331 	if (!mod_timer(&idev->rs_timer, jiffies + when))
332 		in6_dev_hold(idev);
333 }
334 
addrconf_mod_dad_work(struct inet6_ifaddr * ifp,unsigned long delay)335 static void addrconf_mod_dad_work(struct inet6_ifaddr *ifp,
336 				   unsigned long delay)
337 {
338 	in6_ifa_hold(ifp);
339 	if (mod_delayed_work(addrconf_wq, &ifp->dad_work, delay))
340 		in6_ifa_put(ifp);
341 }
342 
snmp6_alloc_dev(struct inet6_dev * idev)343 static int snmp6_alloc_dev(struct inet6_dev *idev)
344 {
345 	int i;
346 
347 	idev->stats.ipv6 = alloc_percpu_gfp(struct ipstats_mib, GFP_KERNEL_ACCOUNT);
348 	if (!idev->stats.ipv6)
349 		goto err_ip;
350 
351 	for_each_possible_cpu(i) {
352 		struct ipstats_mib *addrconf_stats;
353 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6, i);
354 		u64_stats_init(&addrconf_stats->syncp);
355 	}
356 
357 
358 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
359 					GFP_KERNEL);
360 	if (!idev->stats.icmpv6dev)
361 		goto err_icmp;
362 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
363 					   GFP_KERNEL_ACCOUNT);
364 	if (!idev->stats.icmpv6msgdev)
365 		goto err_icmpmsg;
366 
367 	return 0;
368 
369 err_icmpmsg:
370 	kfree(idev->stats.icmpv6dev);
371 err_icmp:
372 	free_percpu(idev->stats.ipv6);
373 err_ip:
374 	return -ENOMEM;
375 }
376 
ipv6_add_dev(struct net_device * dev)377 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
378 {
379 	struct inet6_dev *ndev;
380 	int err = -ENOMEM;
381 
382 	ASSERT_RTNL();
383 	netdev_ops_assert_locked(dev);
384 
385 	if (dev->mtu < IPV6_MIN_MTU && dev != blackhole_netdev)
386 		return ERR_PTR(-EINVAL);
387 
388 	ndev = kzalloc(sizeof(*ndev), GFP_KERNEL_ACCOUNT);
389 	if (!ndev)
390 		return ERR_PTR(err);
391 
392 	rwlock_init(&ndev->lock);
393 	ndev->dev = dev;
394 	INIT_LIST_HEAD(&ndev->addr_list);
395 	timer_setup(&ndev->rs_timer, addrconf_rs_timer, 0);
396 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
397 
398 	if (ndev->cnf.stable_secret.initialized)
399 		ndev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
400 
401 	ndev->cnf.mtu6 = dev->mtu;
402 	ndev->ra_mtu = 0;
403 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
404 	if (!ndev->nd_parms) {
405 		kfree(ndev);
406 		return ERR_PTR(err);
407 	}
408 	if (ndev->cnf.forwarding)
409 		netif_disable_lro(dev);
410 	/* We refer to the device */
411 	netdev_hold(dev, &ndev->dev_tracker, GFP_KERNEL);
412 
413 	if (snmp6_alloc_dev(ndev) < 0) {
414 		netdev_dbg(dev, "%s: cannot allocate memory for statistics\n",
415 			   __func__);
416 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
417 		netdev_put(dev, &ndev->dev_tracker);
418 		kfree(ndev);
419 		return ERR_PTR(err);
420 	}
421 
422 	if (dev != blackhole_netdev) {
423 		if (snmp6_register_dev(ndev) < 0) {
424 			netdev_dbg(dev, "%s: cannot create /proc/net/dev_snmp6/%s\n",
425 				   __func__, dev->name);
426 			goto err_release;
427 		}
428 	}
429 	/* One reference from device. */
430 	refcount_set(&ndev->refcnt, 1);
431 
432 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
433 		ndev->cnf.accept_dad = -1;
434 
435 #if IS_ENABLED(CONFIG_IPV6_SIT)
436 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
437 		pr_info("%s: Disabled Multicast RS\n", dev->name);
438 		ndev->cnf.rtr_solicits = 0;
439 	}
440 #endif
441 
442 	INIT_LIST_HEAD(&ndev->tempaddr_list);
443 	ndev->desync_factor = U32_MAX;
444 	if ((dev->flags&IFF_LOOPBACK) ||
445 	    dev->type == ARPHRD_TUNNEL ||
446 	    dev->type == ARPHRD_TUNNEL6 ||
447 	    dev->type == ARPHRD_SIT ||
448 	    dev->type == ARPHRD_NONE) {
449 		ndev->cnf.use_tempaddr = -1;
450 	}
451 
452 	ndev->token = in6addr_any;
453 
454 	if (netif_running(dev) && addrconf_link_ready(dev))
455 		ndev->if_flags |= IF_READY;
456 
457 	ipv6_mc_init_dev(ndev);
458 	ndev->tstamp = jiffies;
459 	if (dev != blackhole_netdev) {
460 		err = addrconf_sysctl_register(ndev);
461 		if (err) {
462 			ipv6_mc_destroy_dev(ndev);
463 			snmp6_unregister_dev(ndev);
464 			goto err_release;
465 		}
466 	}
467 	/* protected by rtnl_lock */
468 	rcu_assign_pointer(dev->ip6_ptr, ndev);
469 
470 	if (dev != blackhole_netdev) {
471 		/* Join interface-local all-node multicast group */
472 		ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
473 
474 		/* Join all-node multicast group */
475 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
476 
477 		/* Join all-router multicast group if forwarding is set */
478 		if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
479 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
480 	}
481 	return ndev;
482 
483 err_release:
484 	neigh_parms_release(&nd_tbl, ndev->nd_parms);
485 	ndev->dead = 1;
486 	in6_dev_finish_destroy(ndev);
487 	return ERR_PTR(err);
488 }
489 
ipv6_find_idev(struct net_device * dev)490 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
491 {
492 	struct inet6_dev *idev;
493 
494 	ASSERT_RTNL();
495 
496 	idev = __in6_dev_get(dev);
497 	if (!idev) {
498 		idev = ipv6_add_dev(dev);
499 		if (IS_ERR(idev))
500 			return idev;
501 	}
502 
503 	if (dev->flags&IFF_UP)
504 		ipv6_mc_up(idev);
505 	return idev;
506 }
507 
inet6_netconf_msgsize_devconf(int type)508 static int inet6_netconf_msgsize_devconf(int type)
509 {
510 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
511 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
512 	bool all = false;
513 
514 	if (type == NETCONFA_ALL)
515 		all = true;
516 
517 	if (all || type == NETCONFA_FORWARDING)
518 		size += nla_total_size(4);
519 #ifdef CONFIG_IPV6_MROUTE
520 	if (all || type == NETCONFA_MC_FORWARDING)
521 		size += nla_total_size(4);
522 #endif
523 	if (all || type == NETCONFA_PROXY_NEIGH)
524 		size += nla_total_size(4);
525 
526 	if (all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN)
527 		size += nla_total_size(4);
528 
529 	return size;
530 }
531 
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)532 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
533 				      struct ipv6_devconf *devconf, u32 portid,
534 				      u32 seq, int event, unsigned int flags,
535 				      int type)
536 {
537 	struct nlmsghdr  *nlh;
538 	struct netconfmsg *ncm;
539 	bool all = false;
540 
541 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
542 			flags);
543 	if (!nlh)
544 		return -EMSGSIZE;
545 
546 	if (type == NETCONFA_ALL)
547 		all = true;
548 
549 	ncm = nlmsg_data(nlh);
550 	ncm->ncm_family = AF_INET6;
551 
552 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
553 		goto nla_put_failure;
554 
555 	if (!devconf)
556 		goto out;
557 
558 	if ((all || type == NETCONFA_FORWARDING) &&
559 	    nla_put_s32(skb, NETCONFA_FORWARDING,
560 			READ_ONCE(devconf->forwarding)) < 0)
561 		goto nla_put_failure;
562 #ifdef CONFIG_IPV6_MROUTE
563 	if ((all || type == NETCONFA_MC_FORWARDING) &&
564 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
565 			atomic_read(&devconf->mc_forwarding)) < 0)
566 		goto nla_put_failure;
567 #endif
568 	if ((all || type == NETCONFA_PROXY_NEIGH) &&
569 	    nla_put_s32(skb, NETCONFA_PROXY_NEIGH,
570 			READ_ONCE(devconf->proxy_ndp)) < 0)
571 		goto nla_put_failure;
572 
573 	if ((all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) &&
574 	    nla_put_s32(skb, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
575 			READ_ONCE(devconf->ignore_routes_with_linkdown)) < 0)
576 		goto nla_put_failure;
577 
578 out:
579 	nlmsg_end(skb, nlh);
580 	return 0;
581 
582 nla_put_failure:
583 	nlmsg_cancel(skb, nlh);
584 	return -EMSGSIZE;
585 }
586 
inet6_netconf_notify_devconf(struct net * net,int event,int type,int ifindex,struct ipv6_devconf * devconf)587 void inet6_netconf_notify_devconf(struct net *net, int event, int type,
588 				  int ifindex, struct ipv6_devconf *devconf)
589 {
590 	struct sk_buff *skb;
591 	int err = -ENOBUFS;
592 
593 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_KERNEL);
594 	if (!skb)
595 		goto errout;
596 
597 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
598 					 event, 0, type);
599 	if (err < 0) {
600 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
601 		WARN_ON(err == -EMSGSIZE);
602 		kfree_skb(skb);
603 		goto errout;
604 	}
605 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_KERNEL);
606 	return;
607 errout:
608 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
609 }
610 
611 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
612 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
613 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
614 	[NETCONFA_PROXY_NEIGH]	= { .len = sizeof(int) },
615 	[NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN]	= { .len = sizeof(int) },
616 };
617 
inet6_netconf_valid_get_req(struct sk_buff * skb,const struct nlmsghdr * nlh,struct nlattr ** tb,struct netlink_ext_ack * extack)618 static int inet6_netconf_valid_get_req(struct sk_buff *skb,
619 				       const struct nlmsghdr *nlh,
620 				       struct nlattr **tb,
621 				       struct netlink_ext_ack *extack)
622 {
623 	int i, err;
624 
625 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(struct netconfmsg))) {
626 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf get request");
627 		return -EINVAL;
628 	}
629 
630 	if (!netlink_strict_get_check(skb))
631 		return nlmsg_parse_deprecated(nlh, sizeof(struct netconfmsg),
632 					      tb, NETCONFA_MAX,
633 					      devconf_ipv6_policy, extack);
634 
635 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct netconfmsg),
636 					    tb, NETCONFA_MAX,
637 					    devconf_ipv6_policy, extack);
638 	if (err)
639 		return err;
640 
641 	for (i = 0; i <= NETCONFA_MAX; i++) {
642 		if (!tb[i])
643 			continue;
644 
645 		switch (i) {
646 		case NETCONFA_IFINDEX:
647 			break;
648 		default:
649 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in netconf get request");
650 			return -EINVAL;
651 		}
652 	}
653 
654 	return 0;
655 }
656 
inet6_netconf_get_devconf(struct sk_buff * in_skb,struct nlmsghdr * nlh,struct netlink_ext_ack * extack)657 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
658 				     struct nlmsghdr *nlh,
659 				     struct netlink_ext_ack *extack)
660 {
661 	struct net *net = sock_net(in_skb->sk);
662 	struct nlattr *tb[NETCONFA_MAX+1];
663 	struct inet6_dev *in6_dev = NULL;
664 	struct net_device *dev = NULL;
665 	struct sk_buff *skb;
666 	struct ipv6_devconf *devconf;
667 	int ifindex;
668 	int err;
669 
670 	err = inet6_netconf_valid_get_req(in_skb, nlh, tb, extack);
671 	if (err < 0)
672 		return err;
673 
674 	if (!tb[NETCONFA_IFINDEX])
675 		return -EINVAL;
676 
677 	err = -EINVAL;
678 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
679 	switch (ifindex) {
680 	case NETCONFA_IFINDEX_ALL:
681 		devconf = net->ipv6.devconf_all;
682 		break;
683 	case NETCONFA_IFINDEX_DEFAULT:
684 		devconf = net->ipv6.devconf_dflt;
685 		break;
686 	default:
687 		dev = dev_get_by_index(net, ifindex);
688 		if (!dev)
689 			return -EINVAL;
690 		in6_dev = in6_dev_get(dev);
691 		if (!in6_dev)
692 			goto errout;
693 		devconf = &in6_dev->cnf;
694 		break;
695 	}
696 
697 	err = -ENOBUFS;
698 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL);
699 	if (!skb)
700 		goto errout;
701 
702 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
703 					 NETLINK_CB(in_skb).portid,
704 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
705 					 NETCONFA_ALL);
706 	if (err < 0) {
707 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
708 		WARN_ON(err == -EMSGSIZE);
709 		kfree_skb(skb);
710 		goto errout;
711 	}
712 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
713 errout:
714 	if (in6_dev)
715 		in6_dev_put(in6_dev);
716 	dev_put(dev);
717 	return err;
718 }
719 
720 /* Combine dev_addr_genid and dev_base_seq to detect changes.
721  */
inet6_base_seq(const struct net * net)722 static u32 inet6_base_seq(const struct net *net)
723 {
724 	u32 res = atomic_read(&net->ipv6.dev_addr_genid) +
725 		  READ_ONCE(net->dev_base_seq);
726 
727 	/* Must not return 0 (see nl_dump_check_consistent()).
728 	 * Chose a value far away from 0.
729 	 */
730 	if (!res)
731 		res = 0x80000000;
732 	return res;
733 }
734 
inet6_netconf_dump_devconf(struct sk_buff * skb,struct netlink_callback * cb)735 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
736 				      struct netlink_callback *cb)
737 {
738 	const struct nlmsghdr *nlh = cb->nlh;
739 	struct net *net = sock_net(skb->sk);
740 	struct {
741 		unsigned long ifindex;
742 		unsigned int all_default;
743 	} *ctx = (void *)cb->ctx;
744 	struct net_device *dev;
745 	struct inet6_dev *idev;
746 	int err = 0;
747 
748 	if (cb->strict_check) {
749 		struct netlink_ext_ack *extack = cb->extack;
750 		struct netconfmsg *ncm;
751 
752 		if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ncm))) {
753 			NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf dump request");
754 			return -EINVAL;
755 		}
756 
757 		if (nlmsg_attrlen(nlh, sizeof(*ncm))) {
758 			NL_SET_ERR_MSG_MOD(extack, "Invalid data after header in netconf dump request");
759 			return -EINVAL;
760 		}
761 	}
762 
763 	rcu_read_lock();
764 	for_each_netdev_dump(net, dev, ctx->ifindex) {
765 		idev = __in6_dev_get(dev);
766 		if (!idev)
767 			continue;
768 		err = inet6_netconf_fill_devconf(skb, dev->ifindex,
769 					         &idev->cnf,
770 						 NETLINK_CB(cb->skb).portid,
771 						 nlh->nlmsg_seq,
772 						 RTM_NEWNETCONF,
773 						 NLM_F_MULTI,
774 						 NETCONFA_ALL);
775 		if (err < 0)
776 			goto done;
777 	}
778 	if (ctx->all_default == 0) {
779 		err = inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
780 						 net->ipv6.devconf_all,
781 						 NETLINK_CB(cb->skb).portid,
782 						 nlh->nlmsg_seq,
783 						 RTM_NEWNETCONF, NLM_F_MULTI,
784 						 NETCONFA_ALL);
785 		if (err < 0)
786 			goto done;
787 		ctx->all_default++;
788 	}
789 	if (ctx->all_default == 1) {
790 		err = inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
791 						 net->ipv6.devconf_dflt,
792 						 NETLINK_CB(cb->skb).portid,
793 						 nlh->nlmsg_seq,
794 						 RTM_NEWNETCONF, NLM_F_MULTI,
795 						 NETCONFA_ALL);
796 		if (err < 0)
797 			goto done;
798 		ctx->all_default++;
799 	}
800 done:
801 	rcu_read_unlock();
802 	return err;
803 }
804 
805 #ifdef CONFIG_SYSCTL
dev_forward_change(struct inet6_dev * idev)806 static void dev_forward_change(struct inet6_dev *idev)
807 {
808 	struct net_device *dev;
809 	struct inet6_ifaddr *ifa;
810 	LIST_HEAD(tmp_addr_list);
811 
812 	if (!idev)
813 		return;
814 	dev = idev->dev;
815 	if (idev->cnf.forwarding)
816 		dev_disable_lro(dev);
817 	if (dev->flags & IFF_MULTICAST) {
818 		if (idev->cnf.forwarding) {
819 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
820 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
821 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
822 		} else {
823 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
824 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
825 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
826 		}
827 	}
828 
829 	read_lock_bh(&idev->lock);
830 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
831 		if (ifa->flags&IFA_F_TENTATIVE)
832 			continue;
833 		list_add_tail(&ifa->if_list_aux, &tmp_addr_list);
834 	}
835 	read_unlock_bh(&idev->lock);
836 
837 	while (!list_empty(&tmp_addr_list)) {
838 		ifa = list_first_entry(&tmp_addr_list,
839 				       struct inet6_ifaddr, if_list_aux);
840 		list_del(&ifa->if_list_aux);
841 		if (idev->cnf.forwarding)
842 			addrconf_join_anycast(ifa);
843 		else
844 			addrconf_leave_anycast(ifa);
845 	}
846 
847 	inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
848 				     NETCONFA_FORWARDING,
849 				     dev->ifindex, &idev->cnf);
850 }
851 
852 
addrconf_forward_change(struct net * net,__s32 newf)853 static void addrconf_forward_change(struct net *net, __s32 newf)
854 {
855 	struct net_device *dev;
856 	struct inet6_dev *idev;
857 
858 	for_each_netdev(net, dev) {
859 		idev = __in6_dev_get_rtnl_net(dev);
860 		if (idev) {
861 			int changed = (!idev->cnf.forwarding) ^ (!newf);
862 			/* Disabling all.forwarding sets 0 to force_forwarding for all interfaces */
863 			if (newf == 0)
864 				WRITE_ONCE(idev->cnf.force_forwarding, 0);
865 
866 			WRITE_ONCE(idev->cnf.forwarding, newf);
867 			if (changed)
868 				dev_forward_change(idev);
869 		}
870 	}
871 }
872 
addrconf_fixup_forwarding(const struct ctl_table * table,int * p,int newf)873 static int addrconf_fixup_forwarding(const struct ctl_table *table, int *p, int newf)
874 {
875 	struct net *net = (struct net *)table->extra2;
876 	int old;
877 
878 	if (!rtnl_net_trylock(net))
879 		return restart_syscall();
880 
881 	old = *p;
882 	WRITE_ONCE(*p, newf);
883 
884 	if (p == &net->ipv6.devconf_dflt->forwarding) {
885 		if ((!newf) ^ (!old))
886 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
887 						     NETCONFA_FORWARDING,
888 						     NETCONFA_IFINDEX_DEFAULT,
889 						     net->ipv6.devconf_dflt);
890 		rtnl_net_unlock(net);
891 		return 0;
892 	}
893 
894 	if (p == &net->ipv6.devconf_all->forwarding) {
895 		int old_dflt = net->ipv6.devconf_dflt->forwarding;
896 
897 		WRITE_ONCE(net->ipv6.devconf_dflt->forwarding, newf);
898 		if ((!newf) ^ (!old_dflt))
899 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
900 						     NETCONFA_FORWARDING,
901 						     NETCONFA_IFINDEX_DEFAULT,
902 						     net->ipv6.devconf_dflt);
903 
904 		addrconf_forward_change(net, newf);
905 		if ((!newf) ^ (!old))
906 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
907 						     NETCONFA_FORWARDING,
908 						     NETCONFA_IFINDEX_ALL,
909 						     net->ipv6.devconf_all);
910 	} else if ((!newf) ^ (!old))
911 		dev_forward_change((struct inet6_dev *)table->extra1);
912 	rtnl_net_unlock(net);
913 
914 	if (newf)
915 		rt6_purge_dflt_routers(net);
916 	return 1;
917 }
918 
addrconf_linkdown_change(struct net * net,__s32 newf)919 static void addrconf_linkdown_change(struct net *net, __s32 newf)
920 {
921 	struct net_device *dev;
922 	struct inet6_dev *idev;
923 
924 	for_each_netdev(net, dev) {
925 		idev = __in6_dev_get_rtnl_net(dev);
926 		if (idev) {
927 			int changed = (!idev->cnf.ignore_routes_with_linkdown) ^ (!newf);
928 
929 			WRITE_ONCE(idev->cnf.ignore_routes_with_linkdown, newf);
930 			if (changed)
931 				inet6_netconf_notify_devconf(dev_net(dev),
932 							     RTM_NEWNETCONF,
933 							     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
934 							     dev->ifindex,
935 							     &idev->cnf);
936 		}
937 	}
938 }
939 
addrconf_fixup_linkdown(const struct ctl_table * table,int * p,int newf)940 static int addrconf_fixup_linkdown(const struct ctl_table *table, int *p, int newf)
941 {
942 	struct net *net = (struct net *)table->extra2;
943 	int old;
944 
945 	if (!rtnl_net_trylock(net))
946 		return restart_syscall();
947 
948 	old = *p;
949 	WRITE_ONCE(*p, newf);
950 
951 	if (p == &net->ipv6.devconf_dflt->ignore_routes_with_linkdown) {
952 		if ((!newf) ^ (!old))
953 			inet6_netconf_notify_devconf(net,
954 						     RTM_NEWNETCONF,
955 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
956 						     NETCONFA_IFINDEX_DEFAULT,
957 						     net->ipv6.devconf_dflt);
958 		rtnl_net_unlock(net);
959 		return 0;
960 	}
961 
962 	if (p == &net->ipv6.devconf_all->ignore_routes_with_linkdown) {
963 		WRITE_ONCE(net->ipv6.devconf_dflt->ignore_routes_with_linkdown, newf);
964 		addrconf_linkdown_change(net, newf);
965 		if ((!newf) ^ (!old))
966 			inet6_netconf_notify_devconf(net,
967 						     RTM_NEWNETCONF,
968 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
969 						     NETCONFA_IFINDEX_ALL,
970 						     net->ipv6.devconf_all);
971 	}
972 
973 	rtnl_net_unlock(net);
974 
975 	return 1;
976 }
977 
978 #endif
979 
980 /* Nobody refers to this ifaddr, destroy it */
inet6_ifa_finish_destroy(struct inet6_ifaddr * ifp)981 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
982 {
983 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
984 
985 #ifdef NET_REFCNT_DEBUG
986 	pr_debug("%s\n", __func__);
987 #endif
988 
989 	in6_dev_put(ifp->idev);
990 
991 	if (cancel_delayed_work(&ifp->dad_work))
992 		pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
993 			  ifp);
994 
995 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
996 		pr_warn("Freeing alive inet6 address %p\n", ifp);
997 		return;
998 	}
999 
1000 	kfree_rcu(ifp, rcu);
1001 }
1002 
1003 static void
ipv6_link_dev_addr(struct inet6_dev * idev,struct inet6_ifaddr * ifp)1004 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
1005 {
1006 	struct list_head *p;
1007 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
1008 
1009 	/*
1010 	 * Each device address list is sorted in order of scope -
1011 	 * global before linklocal.
1012 	 */
1013 	list_for_each(p, &idev->addr_list) {
1014 		struct inet6_ifaddr *ifa
1015 			= list_entry(p, struct inet6_ifaddr, if_list);
1016 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
1017 			break;
1018 	}
1019 
1020 	list_add_tail_rcu(&ifp->if_list, p);
1021 }
1022 
inet6_addr_hash(const struct net * net,const struct in6_addr * addr)1023 static u32 inet6_addr_hash(const struct net *net, const struct in6_addr *addr)
1024 {
1025 	u32 val = __ipv6_addr_jhash(addr, net_hash_mix(net));
1026 
1027 	return hash_32(val, IN6_ADDR_HSIZE_SHIFT);
1028 }
1029 
ipv6_chk_same_addr(struct net * net,const struct in6_addr * addr,struct net_device * dev,unsigned int hash)1030 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
1031 			       struct net_device *dev, unsigned int hash)
1032 {
1033 	struct inet6_ifaddr *ifp;
1034 
1035 	hlist_for_each_entry(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
1036 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1037 			if (!dev || ifp->idev->dev == dev)
1038 				return true;
1039 		}
1040 	}
1041 	return false;
1042 }
1043 
ipv6_add_addr_hash(struct net_device * dev,struct inet6_ifaddr * ifa)1044 static int ipv6_add_addr_hash(struct net_device *dev, struct inet6_ifaddr *ifa)
1045 {
1046 	struct net *net = dev_net(dev);
1047 	unsigned int hash = inet6_addr_hash(net, &ifa->addr);
1048 	int err = 0;
1049 
1050 	spin_lock_bh(&net->ipv6.addrconf_hash_lock);
1051 
1052 	/* Ignore adding duplicate addresses on an interface */
1053 	if (ipv6_chk_same_addr(net, &ifa->addr, dev, hash)) {
1054 		netdev_dbg(dev, "ipv6_add_addr: already assigned\n");
1055 		err = -EEXIST;
1056 	} else {
1057 		hlist_add_head_rcu(&ifa->addr_lst, &net->ipv6.inet6_addr_lst[hash]);
1058 	}
1059 
1060 	spin_unlock_bh(&net->ipv6.addrconf_hash_lock);
1061 
1062 	return err;
1063 }
1064 
1065 /* On success it returns ifp with increased reference count */
1066 
1067 static struct inet6_ifaddr *
ipv6_add_addr(struct inet6_dev * idev,struct ifa6_config * cfg,bool can_block,struct netlink_ext_ack * extack)1068 ipv6_add_addr(struct inet6_dev *idev, struct ifa6_config *cfg,
1069 	      bool can_block, struct netlink_ext_ack *extack)
1070 {
1071 	gfp_t gfp_flags = can_block ? GFP_KERNEL : GFP_ATOMIC;
1072 	int addr_type = ipv6_addr_type(cfg->pfx);
1073 	struct net *net = dev_net(idev->dev);
1074 	struct inet6_ifaddr *ifa = NULL;
1075 	struct fib6_info *f6i = NULL;
1076 	int err = 0;
1077 
1078 	if (addr_type == IPV6_ADDR_ANY) {
1079 		NL_SET_ERR_MSG_MOD(extack, "Invalid address");
1080 		return ERR_PTR(-EADDRNOTAVAIL);
1081 	} else if (addr_type & IPV6_ADDR_MULTICAST &&
1082 		   !(cfg->ifa_flags & IFA_F_MCAUTOJOIN)) {
1083 		NL_SET_ERR_MSG_MOD(extack, "Cannot assign multicast address without \"IFA_F_MCAUTOJOIN\" flag");
1084 		return ERR_PTR(-EADDRNOTAVAIL);
1085 	} else if (!(idev->dev->flags & IFF_LOOPBACK) &&
1086 		   !netif_is_l3_master(idev->dev) &&
1087 		   addr_type & IPV6_ADDR_LOOPBACK) {
1088 		NL_SET_ERR_MSG_MOD(extack, "Cannot assign loopback address on this device");
1089 		return ERR_PTR(-EADDRNOTAVAIL);
1090 	}
1091 
1092 	if (idev->dead) {
1093 		NL_SET_ERR_MSG_MOD(extack, "device is going away");
1094 		err = -ENODEV;
1095 		goto out;
1096 	}
1097 
1098 	if (idev->cnf.disable_ipv6) {
1099 		NL_SET_ERR_MSG_MOD(extack, "IPv6 is disabled on this device");
1100 		err = -EACCES;
1101 		goto out;
1102 	}
1103 
1104 	/* validator notifier needs to be blocking;
1105 	 * do not call in atomic context
1106 	 */
1107 	if (can_block) {
1108 		struct in6_validator_info i6vi = {
1109 			.i6vi_addr = *cfg->pfx,
1110 			.i6vi_dev = idev,
1111 			.extack = extack,
1112 		};
1113 
1114 		err = inet6addr_validator_notifier_call_chain(NETDEV_UP, &i6vi);
1115 		err = notifier_to_errno(err);
1116 		if (err < 0)
1117 			goto out;
1118 	}
1119 
1120 	ifa = kzalloc(sizeof(*ifa), gfp_flags | __GFP_ACCOUNT);
1121 	if (!ifa) {
1122 		err = -ENOBUFS;
1123 		goto out;
1124 	}
1125 
1126 	f6i = addrconf_f6i_alloc(net, idev, cfg->pfx, false, gfp_flags, extack);
1127 	if (IS_ERR(f6i)) {
1128 		err = PTR_ERR(f6i);
1129 		f6i = NULL;
1130 		goto out;
1131 	}
1132 
1133 	neigh_parms_data_state_setall(idev->nd_parms);
1134 
1135 	ifa->addr = *cfg->pfx;
1136 	if (cfg->peer_pfx)
1137 		ifa->peer_addr = *cfg->peer_pfx;
1138 
1139 	spin_lock_init(&ifa->lock);
1140 	INIT_DELAYED_WORK(&ifa->dad_work, addrconf_dad_work);
1141 	INIT_HLIST_NODE(&ifa->addr_lst);
1142 	ifa->scope = cfg->scope;
1143 	ifa->prefix_len = cfg->plen;
1144 	ifa->rt_priority = cfg->rt_priority;
1145 	ifa->flags = cfg->ifa_flags;
1146 	ifa->ifa_proto = cfg->ifa_proto;
1147 	/* No need to add the TENTATIVE flag for addresses with NODAD */
1148 	if (!(cfg->ifa_flags & IFA_F_NODAD))
1149 		ifa->flags |= IFA_F_TENTATIVE;
1150 	ifa->valid_lft = cfg->valid_lft;
1151 	ifa->prefered_lft = cfg->preferred_lft;
1152 	ifa->cstamp = ifa->tstamp = jiffies;
1153 	ifa->tokenized = false;
1154 
1155 	ifa->rt = f6i;
1156 
1157 	ifa->idev = idev;
1158 	in6_dev_hold(idev);
1159 
1160 	/* For caller */
1161 	refcount_set(&ifa->refcnt, 1);
1162 
1163 	rcu_read_lock();
1164 
1165 	err = ipv6_add_addr_hash(idev->dev, ifa);
1166 	if (err < 0) {
1167 		rcu_read_unlock();
1168 		goto out;
1169 	}
1170 
1171 	write_lock_bh(&idev->lock);
1172 
1173 	/* Add to inet6_dev unicast addr list. */
1174 	ipv6_link_dev_addr(idev, ifa);
1175 
1176 	if (ifa->flags&IFA_F_TEMPORARY) {
1177 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
1178 		in6_ifa_hold(ifa);
1179 	}
1180 
1181 	in6_ifa_hold(ifa);
1182 	write_unlock_bh(&idev->lock);
1183 
1184 	rcu_read_unlock();
1185 
1186 	inet6addr_notifier_call_chain(NETDEV_UP, ifa);
1187 out:
1188 	if (unlikely(err < 0)) {
1189 		fib6_info_release(f6i);
1190 
1191 		if (ifa) {
1192 			if (ifa->idev)
1193 				in6_dev_put(ifa->idev);
1194 			kfree(ifa);
1195 		}
1196 		ifa = ERR_PTR(err);
1197 	}
1198 
1199 	return ifa;
1200 }
1201 
1202 enum cleanup_prefix_rt_t {
1203 	CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */
1204 	CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */
1205 	CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */
1206 };
1207 
1208 /*
1209  * Check, whether the prefix for ifp would still need a prefix route
1210  * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*
1211  * constants.
1212  *
1213  * 1) we don't purge prefix if address was not permanent.
1214  *    prefix is managed by its own lifetime.
1215  * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.
1216  * 3) if there are no addresses, delete prefix.
1217  * 4) if there are still other permanent address(es),
1218  *    corresponding prefix is still permanent.
1219  * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,
1220  *    don't purge the prefix, assume user space is managing it.
1221  * 6) otherwise, update prefix lifetime to the
1222  *    longest valid lifetime among the corresponding
1223  *    addresses on the device.
1224  *    Note: subsequent RA will update lifetime.
1225  **/
1226 static enum cleanup_prefix_rt_t
check_cleanup_prefix_route(struct inet6_ifaddr * ifp,unsigned long * expires)1227 check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)
1228 {
1229 	struct inet6_ifaddr *ifa;
1230 	struct inet6_dev *idev = ifp->idev;
1231 	unsigned long lifetime;
1232 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;
1233 
1234 	*expires = jiffies;
1235 
1236 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
1237 		if (ifa == ifp)
1238 			continue;
1239 		if (ifa->prefix_len != ifp->prefix_len ||
1240 		    !ipv6_prefix_equal(&ifa->addr, &ifp->addr,
1241 				       ifp->prefix_len))
1242 			continue;
1243 		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
1244 			return CLEANUP_PREFIX_RT_NOP;
1245 
1246 		action = CLEANUP_PREFIX_RT_EXPIRE;
1247 
1248 		spin_lock(&ifa->lock);
1249 
1250 		lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
1251 		/*
1252 		 * Note: Because this address is
1253 		 * not permanent, lifetime <
1254 		 * LONG_MAX / HZ here.
1255 		 */
1256 		if (time_before(*expires, ifa->tstamp + lifetime * HZ))
1257 			*expires = ifa->tstamp + lifetime * HZ;
1258 		spin_unlock(&ifa->lock);
1259 	}
1260 
1261 	return action;
1262 }
1263 
1264 static void
cleanup_prefix_route(struct inet6_ifaddr * ifp,unsigned long expires,bool del_rt,bool del_peer)1265 cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires,
1266 		     bool del_rt, bool del_peer)
1267 {
1268 	struct fib6_table *table;
1269 	struct fib6_info *f6i;
1270 
1271 	f6i = addrconf_get_prefix_route(del_peer ? &ifp->peer_addr : &ifp->addr,
1272 					ifp->prefix_len,
1273 					ifp->idev->dev, 0, RTF_DEFAULT, true);
1274 	if (f6i) {
1275 		if (del_rt)
1276 			ip6_del_rt(dev_net(ifp->idev->dev), f6i, false);
1277 		else {
1278 			if (!(f6i->fib6_flags & RTF_EXPIRES)) {
1279 				table = f6i->fib6_table;
1280 				spin_lock_bh(&table->tb6_lock);
1281 
1282 				fib6_set_expires(f6i, expires);
1283 				fib6_add_gc_list(f6i);
1284 
1285 				spin_unlock_bh(&table->tb6_lock);
1286 			}
1287 			fib6_info_release(f6i);
1288 		}
1289 	}
1290 }
1291 
1292 
1293 /* This function wants to get referenced ifp and releases it before return */
1294 
ipv6_del_addr(struct inet6_ifaddr * ifp)1295 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
1296 {
1297 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;
1298 	struct net *net = dev_net(ifp->idev->dev);
1299 	unsigned long expires;
1300 	int state;
1301 
1302 	ASSERT_RTNL();
1303 
1304 	spin_lock_bh(&ifp->lock);
1305 	state = ifp->state;
1306 	ifp->state = INET6_IFADDR_STATE_DEAD;
1307 	spin_unlock_bh(&ifp->lock);
1308 
1309 	if (state == INET6_IFADDR_STATE_DEAD)
1310 		goto out;
1311 
1312 	spin_lock_bh(&net->ipv6.addrconf_hash_lock);
1313 	hlist_del_init_rcu(&ifp->addr_lst);
1314 	spin_unlock_bh(&net->ipv6.addrconf_hash_lock);
1315 
1316 	write_lock_bh(&ifp->idev->lock);
1317 
1318 	if (ifp->flags&IFA_F_TEMPORARY) {
1319 		list_del(&ifp->tmp_list);
1320 		if (ifp->ifpub) {
1321 			in6_ifa_put(ifp->ifpub);
1322 			ifp->ifpub = NULL;
1323 		}
1324 		__in6_ifa_put(ifp);
1325 	}
1326 
1327 	if (ifp->flags & IFA_F_PERMANENT && !(ifp->flags & IFA_F_NOPREFIXROUTE))
1328 		action = check_cleanup_prefix_route(ifp, &expires);
1329 
1330 	list_del_rcu(&ifp->if_list);
1331 	__in6_ifa_put(ifp);
1332 
1333 	write_unlock_bh(&ifp->idev->lock);
1334 
1335 	addrconf_del_dad_work(ifp);
1336 
1337 	ipv6_ifa_notify(RTM_DELADDR, ifp);
1338 
1339 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
1340 
1341 	if (action != CLEANUP_PREFIX_RT_NOP) {
1342 		cleanup_prefix_route(ifp, expires,
1343 			action == CLEANUP_PREFIX_RT_DEL, false);
1344 	}
1345 
1346 	/* clean up prefsrc entries */
1347 	rt6_remove_prefsrc(ifp);
1348 out:
1349 	in6_ifa_put(ifp);
1350 }
1351 
ipv6_get_regen_advance(const struct inet6_dev * idev)1352 static unsigned long ipv6_get_regen_advance(const struct inet6_dev *idev)
1353 {
1354 	return READ_ONCE(idev->cnf.regen_min_advance) +
1355 		READ_ONCE(idev->cnf.regen_max_retry) *
1356 		READ_ONCE(idev->cnf.dad_transmits) *
1357 		max(NEIGH_VAR(idev->nd_parms, RETRANS_TIME), HZ/100) / HZ;
1358 }
1359 
ipv6_create_tempaddr(struct inet6_ifaddr * ifp,bool block)1360 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, bool block)
1361 {
1362 	struct inet6_dev *idev = ifp->idev;
1363 	unsigned long tmp_tstamp, age;
1364 	unsigned long regen_advance;
1365 	unsigned long now = jiffies;
1366 	u32 if_public_preferred_lft;
1367 	s32 cnf_temp_preferred_lft;
1368 	struct inet6_ifaddr *ift;
1369 	struct ifa6_config cfg;
1370 	long max_desync_factor;
1371 	struct in6_addr addr;
1372 	int ret = 0;
1373 
1374 	write_lock_bh(&idev->lock);
1375 
1376 retry:
1377 	in6_dev_hold(idev);
1378 	if (READ_ONCE(idev->cnf.use_tempaddr) <= 0) {
1379 		write_unlock_bh(&idev->lock);
1380 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1381 		in6_dev_put(idev);
1382 		ret = -1;
1383 		goto out;
1384 	}
1385 	spin_lock_bh(&ifp->lock);
1386 	if (ifp->regen_count++ >= READ_ONCE(idev->cnf.regen_max_retry)) {
1387 		WRITE_ONCE(idev->cnf.use_tempaddr, -1);	/*XXX*/
1388 		spin_unlock_bh(&ifp->lock);
1389 		write_unlock_bh(&idev->lock);
1390 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1391 			__func__);
1392 		in6_dev_put(idev);
1393 		ret = -1;
1394 		goto out;
1395 	}
1396 	in6_ifa_hold(ifp);
1397 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1398 	ipv6_gen_rnd_iid(&addr);
1399 
1400 	age = (now - ifp->tstamp) / HZ;
1401 
1402 	regen_advance = ipv6_get_regen_advance(idev);
1403 
1404 	/* recalculate max_desync_factor each time and update
1405 	 * idev->desync_factor if it's larger
1406 	 */
1407 	cnf_temp_preferred_lft = READ_ONCE(idev->cnf.temp_prefered_lft);
1408 	max_desync_factor = min_t(long,
1409 				  READ_ONCE(idev->cnf.max_desync_factor),
1410 				  cnf_temp_preferred_lft - regen_advance);
1411 
1412 	if (unlikely(idev->desync_factor > max_desync_factor)) {
1413 		if (max_desync_factor > 0) {
1414 			get_random_bytes(&idev->desync_factor,
1415 					 sizeof(idev->desync_factor));
1416 			idev->desync_factor %= max_desync_factor;
1417 		} else {
1418 			idev->desync_factor = 0;
1419 		}
1420 	}
1421 
1422 	if_public_preferred_lft = ifp->prefered_lft;
1423 
1424 	memset(&cfg, 0, sizeof(cfg));
1425 	cfg.valid_lft = min_t(__u32, ifp->valid_lft,
1426 			      READ_ONCE(idev->cnf.temp_valid_lft) + age);
1427 	cfg.preferred_lft = cnf_temp_preferred_lft + age - idev->desync_factor;
1428 	cfg.preferred_lft = min_t(__u32, if_public_preferred_lft, cfg.preferred_lft);
1429 	cfg.preferred_lft = min_t(__u32, cfg.valid_lft, cfg.preferred_lft);
1430 
1431 	cfg.plen = ifp->prefix_len;
1432 	tmp_tstamp = ifp->tstamp;
1433 	spin_unlock_bh(&ifp->lock);
1434 
1435 	write_unlock_bh(&idev->lock);
1436 
1437 	/* From RFC 4941:
1438 	 *
1439 	 *     A temporary address is created only if this calculated Preferred
1440 	 *     Lifetime is greater than REGEN_ADVANCE time units.  In
1441 	 *     particular, an implementation must not create a temporary address
1442 	 *     with a zero Preferred Lifetime.
1443 	 *
1444 	 *     ...
1445 	 *
1446 	 *     When creating a temporary address, the lifetime values MUST be
1447 	 *     derived from the corresponding prefix as follows:
1448 	 *
1449 	 *     ...
1450 	 *
1451 	 *     *  Its Preferred Lifetime is the lower of the Preferred Lifetime
1452 	 *        of the public address or TEMP_PREFERRED_LIFETIME -
1453 	 *        DESYNC_FACTOR.
1454 	 *
1455 	 * To comply with the RFC's requirements, clamp the preferred lifetime
1456 	 * to a minimum of regen_advance, unless that would exceed valid_lft or
1457 	 * ifp->prefered_lft.
1458 	 *
1459 	 * Use age calculation as in addrconf_verify to avoid unnecessary
1460 	 * temporary addresses being generated.
1461 	 */
1462 	age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1463 	if (cfg.preferred_lft <= regen_advance + age) {
1464 		cfg.preferred_lft = regen_advance + age + 1;
1465 		if (cfg.preferred_lft > cfg.valid_lft ||
1466 		    cfg.preferred_lft > if_public_preferred_lft) {
1467 			in6_ifa_put(ifp);
1468 			in6_dev_put(idev);
1469 			ret = -1;
1470 			goto out;
1471 		}
1472 	}
1473 
1474 	cfg.ifa_flags = IFA_F_TEMPORARY;
1475 	/* set in addrconf_prefix_rcv() */
1476 	if (ifp->flags & IFA_F_OPTIMISTIC)
1477 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
1478 
1479 	cfg.pfx = &addr;
1480 	cfg.scope = ipv6_addr_scope(cfg.pfx);
1481 
1482 	ift = ipv6_add_addr(idev, &cfg, block, NULL);
1483 	if (IS_ERR(ift)) {
1484 		in6_ifa_put(ifp);
1485 		in6_dev_put(idev);
1486 		pr_info("%s: retry temporary address regeneration\n", __func__);
1487 		write_lock_bh(&idev->lock);
1488 		goto retry;
1489 	}
1490 
1491 	spin_lock_bh(&ift->lock);
1492 	ift->ifpub = ifp;
1493 	ift->cstamp = now;
1494 	ift->tstamp = tmp_tstamp;
1495 	spin_unlock_bh(&ift->lock);
1496 
1497 	addrconf_dad_start(ift);
1498 	in6_ifa_put(ift);
1499 	in6_dev_put(idev);
1500 out:
1501 	return ret;
1502 }
1503 
1504 /*
1505  *	Choose an appropriate source address (RFC3484)
1506  */
1507 enum {
1508 	IPV6_SADDR_RULE_INIT = 0,
1509 	IPV6_SADDR_RULE_LOCAL,
1510 	IPV6_SADDR_RULE_SCOPE,
1511 	IPV6_SADDR_RULE_PREFERRED,
1512 #ifdef CONFIG_IPV6_MIP6
1513 	IPV6_SADDR_RULE_HOA,
1514 #endif
1515 	IPV6_SADDR_RULE_OIF,
1516 	IPV6_SADDR_RULE_LABEL,
1517 	IPV6_SADDR_RULE_PRIVACY,
1518 	IPV6_SADDR_RULE_ORCHID,
1519 	IPV6_SADDR_RULE_PREFIX,
1520 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1521 	IPV6_SADDR_RULE_NOT_OPTIMISTIC,
1522 #endif
1523 	IPV6_SADDR_RULE_MAX
1524 };
1525 
1526 struct ipv6_saddr_score {
1527 	int			rule;
1528 	int			addr_type;
1529 	struct inet6_ifaddr	*ifa;
1530 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1531 	int			scopedist;
1532 	int			matchlen;
1533 };
1534 
1535 struct ipv6_saddr_dst {
1536 	const struct in6_addr *addr;
1537 	int ifindex;
1538 	int scope;
1539 	int label;
1540 	unsigned int prefs;
1541 };
1542 
ipv6_saddr_preferred(int type)1543 static inline int ipv6_saddr_preferred(int type)
1544 {
1545 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1546 		return 1;
1547 	return 0;
1548 }
1549 
ipv6_use_optimistic_addr(const struct net * net,const struct inet6_dev * idev)1550 static bool ipv6_use_optimistic_addr(const struct net *net,
1551 				     const struct inet6_dev *idev)
1552 {
1553 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1554 	if (!idev)
1555 		return false;
1556 	if (!READ_ONCE(net->ipv6.devconf_all->optimistic_dad) &&
1557 	    !READ_ONCE(idev->cnf.optimistic_dad))
1558 		return false;
1559 	if (!READ_ONCE(net->ipv6.devconf_all->use_optimistic) &&
1560 	    !READ_ONCE(idev->cnf.use_optimistic))
1561 		return false;
1562 
1563 	return true;
1564 #else
1565 	return false;
1566 #endif
1567 }
1568 
ipv6_allow_optimistic_dad(const struct net * net,const struct inet6_dev * idev)1569 static bool ipv6_allow_optimistic_dad(const struct net *net,
1570 				      const struct inet6_dev *idev)
1571 {
1572 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1573 	if (!idev)
1574 		return false;
1575 	if (!READ_ONCE(net->ipv6.devconf_all->optimistic_dad) &&
1576 	    !READ_ONCE(idev->cnf.optimistic_dad))
1577 		return false;
1578 
1579 	return true;
1580 #else
1581 	return false;
1582 #endif
1583 }
1584 
ipv6_get_saddr_eval(struct net * net,struct ipv6_saddr_score * score,struct ipv6_saddr_dst * dst,int i)1585 static int ipv6_get_saddr_eval(struct net *net,
1586 			       struct ipv6_saddr_score *score,
1587 			       struct ipv6_saddr_dst *dst,
1588 			       int i)
1589 {
1590 	int ret;
1591 
1592 	if (i <= score->rule) {
1593 		switch (i) {
1594 		case IPV6_SADDR_RULE_SCOPE:
1595 			ret = score->scopedist;
1596 			break;
1597 		case IPV6_SADDR_RULE_PREFIX:
1598 			ret = score->matchlen;
1599 			break;
1600 		default:
1601 			ret = !!test_bit(i, score->scorebits);
1602 		}
1603 		goto out;
1604 	}
1605 
1606 	switch (i) {
1607 	case IPV6_SADDR_RULE_INIT:
1608 		/* Rule 0: remember if hiscore is not ready yet */
1609 		ret = !!score->ifa;
1610 		break;
1611 	case IPV6_SADDR_RULE_LOCAL:
1612 		/* Rule 1: Prefer same address */
1613 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1614 		break;
1615 	case IPV6_SADDR_RULE_SCOPE:
1616 		/* Rule 2: Prefer appropriate scope
1617 		 *
1618 		 *      ret
1619 		 *       ^
1620 		 *    -1 |  d 15
1621 		 *    ---+--+-+---> scope
1622 		 *       |
1623 		 *       |             d is scope of the destination.
1624 		 *  B-d  |  \
1625 		 *       |   \      <- smaller scope is better if
1626 		 *  B-15 |    \        if scope is enough for destination.
1627 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1628 		 * d-C-1 | /
1629 		 *       |/         <- greater is better
1630 		 *   -C  /             if scope is not enough for destination.
1631 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1632 		 *
1633 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1634 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1635 		 * Assume B = 0 and we get C > 29.
1636 		 */
1637 		ret = __ipv6_addr_src_scope(score->addr_type);
1638 		if (ret >= dst->scope)
1639 			ret = -ret;
1640 		else
1641 			ret -= 128;	/* 30 is enough */
1642 		score->scopedist = ret;
1643 		break;
1644 	case IPV6_SADDR_RULE_PREFERRED:
1645 	    {
1646 		/* Rule 3: Avoid deprecated and optimistic addresses */
1647 		u8 avoid = IFA_F_DEPRECATED;
1648 
1649 		if (!ipv6_use_optimistic_addr(net, score->ifa->idev))
1650 			avoid |= IFA_F_OPTIMISTIC;
1651 		ret = ipv6_saddr_preferred(score->addr_type) ||
1652 		      !(score->ifa->flags & avoid);
1653 		break;
1654 	    }
1655 #ifdef CONFIG_IPV6_MIP6
1656 	case IPV6_SADDR_RULE_HOA:
1657 	    {
1658 		/* Rule 4: Prefer home address */
1659 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1660 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1661 		break;
1662 	    }
1663 #endif
1664 	case IPV6_SADDR_RULE_OIF:
1665 		/* Rule 5: Prefer outgoing interface */
1666 		ret = (!dst->ifindex ||
1667 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1668 		break;
1669 	case IPV6_SADDR_RULE_LABEL:
1670 		/* Rule 6: Prefer matching label */
1671 		ret = ipv6_addr_label(net,
1672 				      &score->ifa->addr, score->addr_type,
1673 				      score->ifa->idev->dev->ifindex) == dst->label;
1674 		break;
1675 	case IPV6_SADDR_RULE_PRIVACY:
1676 	    {
1677 		/* Rule 7: Prefer public address
1678 		 * Note: prefer temporary address if use_tempaddr >= 2
1679 		 */
1680 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1681 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1682 				READ_ONCE(score->ifa->idev->cnf.use_tempaddr) >= 2;
1683 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1684 		break;
1685 	    }
1686 	case IPV6_SADDR_RULE_ORCHID:
1687 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1688 		 *	    non-ORCHID vs non-ORCHID
1689 		 */
1690 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1691 			ipv6_addr_orchid(dst->addr));
1692 		break;
1693 	case IPV6_SADDR_RULE_PREFIX:
1694 		/* Rule 8: Use longest matching prefix */
1695 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1696 		if (ret > score->ifa->prefix_len)
1697 			ret = score->ifa->prefix_len;
1698 		score->matchlen = ret;
1699 		break;
1700 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1701 	case IPV6_SADDR_RULE_NOT_OPTIMISTIC:
1702 		/* Optimistic addresses still have lower precedence than other
1703 		 * preferred addresses.
1704 		 */
1705 		ret = !(score->ifa->flags & IFA_F_OPTIMISTIC);
1706 		break;
1707 #endif
1708 	default:
1709 		ret = 0;
1710 	}
1711 
1712 	if (ret)
1713 		__set_bit(i, score->scorebits);
1714 	score->rule = i;
1715 out:
1716 	return ret;
1717 }
1718 
__ipv6_dev_get_saddr(struct net * net,struct ipv6_saddr_dst * dst,struct inet6_dev * idev,struct ipv6_saddr_score * scores,int hiscore_idx)1719 static int __ipv6_dev_get_saddr(struct net *net,
1720 				struct ipv6_saddr_dst *dst,
1721 				struct inet6_dev *idev,
1722 				struct ipv6_saddr_score *scores,
1723 				int hiscore_idx)
1724 {
1725 	struct ipv6_saddr_score *score = &scores[1 - hiscore_idx], *hiscore = &scores[hiscore_idx];
1726 
1727 	list_for_each_entry_rcu(score->ifa, &idev->addr_list, if_list) {
1728 		int i;
1729 
1730 		/*
1731 		 * - Tentative Address (RFC2462 section 5.4)
1732 		 *  - A tentative address is not considered
1733 		 *    "assigned to an interface" in the traditional
1734 		 *    sense, unless it is also flagged as optimistic.
1735 		 * - Candidate Source Address (section 4)
1736 		 *  - In any case, anycast addresses, multicast
1737 		 *    addresses, and the unspecified address MUST
1738 		 *    NOT be included in a candidate set.
1739 		 */
1740 		if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1741 		    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1742 			continue;
1743 
1744 		score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1745 
1746 		if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1747 			     score->addr_type & IPV6_ADDR_MULTICAST)) {
1748 			net_dbg_ratelimited("ADDRCONF: unspecified / multicast address assigned as unicast address on %s",
1749 					    idev->dev->name);
1750 			continue;
1751 		}
1752 
1753 		score->rule = -1;
1754 		bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1755 
1756 		for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1757 			int minihiscore, miniscore;
1758 
1759 			minihiscore = ipv6_get_saddr_eval(net, hiscore, dst, i);
1760 			miniscore = ipv6_get_saddr_eval(net, score, dst, i);
1761 
1762 			if (minihiscore > miniscore) {
1763 				if (i == IPV6_SADDR_RULE_SCOPE &&
1764 				    score->scopedist > 0) {
1765 					/*
1766 					 * special case:
1767 					 * each remaining entry
1768 					 * has too small (not enough)
1769 					 * scope, because ifa entries
1770 					 * are sorted by their scope
1771 					 * values.
1772 					 */
1773 					goto out;
1774 				}
1775 				break;
1776 			} else if (minihiscore < miniscore) {
1777 				swap(hiscore, score);
1778 				hiscore_idx = 1 - hiscore_idx;
1779 
1780 				/* restore our iterator */
1781 				score->ifa = hiscore->ifa;
1782 
1783 				break;
1784 			}
1785 		}
1786 	}
1787 out:
1788 	return hiscore_idx;
1789 }
1790 
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)1791 static int ipv6_get_saddr_master(struct net *net,
1792 				 const struct net_device *dst_dev,
1793 				 const struct net_device *master,
1794 				 struct ipv6_saddr_dst *dst,
1795 				 struct ipv6_saddr_score *scores,
1796 				 int hiscore_idx)
1797 {
1798 	struct inet6_dev *idev;
1799 
1800 	idev = __in6_dev_get(dst_dev);
1801 	if (idev)
1802 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1803 						   scores, hiscore_idx);
1804 
1805 	idev = __in6_dev_get(master);
1806 	if (idev)
1807 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1808 						   scores, hiscore_idx);
1809 
1810 	return hiscore_idx;
1811 }
1812 
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)1813 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1814 		       const struct in6_addr *daddr, unsigned int prefs,
1815 		       struct in6_addr *saddr)
1816 {
1817 	struct ipv6_saddr_score scores[2], *hiscore;
1818 	struct ipv6_saddr_dst dst;
1819 	struct inet6_dev *idev;
1820 	struct net_device *dev;
1821 	int dst_type;
1822 	bool use_oif_addr = false;
1823 	int hiscore_idx = 0;
1824 	int ret = 0;
1825 
1826 	dst_type = __ipv6_addr_type(daddr);
1827 	dst.addr = daddr;
1828 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1829 	dst.scope = __ipv6_addr_src_scope(dst_type);
1830 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1831 	dst.prefs = prefs;
1832 
1833 	scores[hiscore_idx].rule = -1;
1834 	scores[hiscore_idx].ifa = NULL;
1835 
1836 	rcu_read_lock();
1837 
1838 	/* Candidate Source Address (section 4)
1839 	 *  - multicast and link-local destination address,
1840 	 *    the set of candidate source address MUST only
1841 	 *    include addresses assigned to interfaces
1842 	 *    belonging to the same link as the outgoing
1843 	 *    interface.
1844 	 * (- For site-local destination addresses, the
1845 	 *    set of candidate source addresses MUST only
1846 	 *    include addresses assigned to interfaces
1847 	 *    belonging to the same site as the outgoing
1848 	 *    interface.)
1849 	 *  - "It is RECOMMENDED that the candidate source addresses
1850 	 *    be the set of unicast addresses assigned to the
1851 	 *    interface that will be used to send to the destination
1852 	 *    (the 'outgoing' interface)." (RFC 6724)
1853 	 */
1854 	if (dst_dev) {
1855 		idev = __in6_dev_get(dst_dev);
1856 		if ((dst_type & IPV6_ADDR_MULTICAST) ||
1857 		    dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL ||
1858 		    (idev && READ_ONCE(idev->cnf.use_oif_addrs_only))) {
1859 			use_oif_addr = true;
1860 		}
1861 	}
1862 
1863 	if (use_oif_addr) {
1864 		if (idev)
1865 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1866 	} else {
1867 		const struct net_device *master;
1868 		int master_idx = 0;
1869 
1870 		/* if dst_dev exists and is enslaved to an L3 device, then
1871 		 * prefer addresses from dst_dev and then the master over
1872 		 * any other enslaved devices in the L3 domain.
1873 		 */
1874 		master = l3mdev_master_dev_rcu(dst_dev);
1875 		if (master) {
1876 			master_idx = master->ifindex;
1877 
1878 			hiscore_idx = ipv6_get_saddr_master(net, dst_dev,
1879 							    master, &dst,
1880 							    scores, hiscore_idx);
1881 
1882 			if (scores[hiscore_idx].ifa &&
1883 			    scores[hiscore_idx].scopedist >= 0)
1884 				goto out;
1885 		}
1886 
1887 		for_each_netdev_rcu(net, dev) {
1888 			/* only consider addresses on devices in the
1889 			 * same L3 domain
1890 			 */
1891 			if (l3mdev_master_ifindex_rcu(dev) != master_idx)
1892 				continue;
1893 			idev = __in6_dev_get(dev);
1894 			if (!idev)
1895 				continue;
1896 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1897 		}
1898 	}
1899 
1900 out:
1901 	hiscore = &scores[hiscore_idx];
1902 	if (!hiscore->ifa)
1903 		ret = -EADDRNOTAVAIL;
1904 	else
1905 		*saddr = hiscore->ifa->addr;
1906 
1907 	rcu_read_unlock();
1908 	return ret;
1909 }
1910 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1911 
__ipv6_get_lladdr(struct inet6_dev * idev,struct in6_addr * addr,u32 banned_flags)1912 static int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1913 			      u32 banned_flags)
1914 {
1915 	struct inet6_ifaddr *ifp;
1916 	int err = -EADDRNOTAVAIL;
1917 
1918 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1919 		if (ifp->scope > IFA_LINK)
1920 			break;
1921 		if (ifp->scope == IFA_LINK &&
1922 		    !(ifp->flags & banned_flags)) {
1923 			*addr = ifp->addr;
1924 			err = 0;
1925 			break;
1926 		}
1927 	}
1928 	return err;
1929 }
1930 
ipv6_get_lladdr(struct net_device * dev,struct in6_addr * addr,u32 banned_flags)1931 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1932 		    u32 banned_flags)
1933 {
1934 	struct inet6_dev *idev;
1935 	int err = -EADDRNOTAVAIL;
1936 
1937 	rcu_read_lock();
1938 	idev = __in6_dev_get(dev);
1939 	if (idev) {
1940 		read_lock_bh(&idev->lock);
1941 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1942 		read_unlock_bh(&idev->lock);
1943 	}
1944 	rcu_read_unlock();
1945 	return err;
1946 }
1947 
ipv6_count_addresses(const struct inet6_dev * idev)1948 static int ipv6_count_addresses(const struct inet6_dev *idev)
1949 {
1950 	const struct inet6_ifaddr *ifp;
1951 	int cnt = 0;
1952 
1953 	rcu_read_lock();
1954 	list_for_each_entry_rcu(ifp, &idev->addr_list, if_list)
1955 		cnt++;
1956 	rcu_read_unlock();
1957 	return cnt;
1958 }
1959 
ipv6_chk_addr(struct net * net,const struct in6_addr * addr,const struct net_device * dev,int strict)1960 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1961 		  const struct net_device *dev, int strict)
1962 {
1963 	return ipv6_chk_addr_and_flags(net, addr, dev, !dev,
1964 				       strict, IFA_F_TENTATIVE);
1965 }
1966 EXPORT_SYMBOL(ipv6_chk_addr);
1967 
1968 /* device argument is used to find the L3 domain of interest. If
1969  * skip_dev_check is set, then the ifp device is not checked against
1970  * the passed in dev argument. So the 2 cases for addresses checks are:
1971  *   1. does the address exist in the L3 domain that dev is part of
1972  *      (skip_dev_check = true), or
1973  *
1974  *   2. does the address exist on the specific device
1975  *      (skip_dev_check = false)
1976  */
1977 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)1978 __ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1979 			  const struct net_device *dev, bool skip_dev_check,
1980 			  int strict, u32 banned_flags)
1981 {
1982 	unsigned int hash = inet6_addr_hash(net, addr);
1983 	struct net_device *l3mdev, *ndev;
1984 	struct inet6_ifaddr *ifp;
1985 	u32 ifp_flags;
1986 
1987 	rcu_read_lock();
1988 
1989 	l3mdev = l3mdev_master_dev_rcu(dev);
1990 	if (skip_dev_check)
1991 		dev = NULL;
1992 
1993 	hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
1994 		ndev = ifp->idev->dev;
1995 
1996 		if (l3mdev_master_dev_rcu(ndev) != l3mdev)
1997 			continue;
1998 
1999 		/* Decouple optimistic from tentative for evaluation here.
2000 		 * Ban optimistic addresses explicitly, when required.
2001 		 */
2002 		ifp_flags = (ifp->flags&IFA_F_OPTIMISTIC)
2003 			    ? (ifp->flags&~IFA_F_TENTATIVE)
2004 			    : ifp->flags;
2005 		if (ipv6_addr_equal(&ifp->addr, addr) &&
2006 		    !(ifp_flags&banned_flags) &&
2007 		    (!dev || ndev == dev ||
2008 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
2009 			rcu_read_unlock();
2010 			return ndev;
2011 		}
2012 	}
2013 
2014 	rcu_read_unlock();
2015 	return NULL;
2016 }
2017 
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)2018 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
2019 			    const struct net_device *dev, bool skip_dev_check,
2020 			    int strict, u32 banned_flags)
2021 {
2022 	return __ipv6_chk_addr_and_flags(net, addr, dev, skip_dev_check,
2023 					 strict, banned_flags) ? 1 : 0;
2024 }
2025 EXPORT_SYMBOL(ipv6_chk_addr_and_flags);
2026 
2027 
2028 /* Compares an address/prefix_len with addresses on device @dev.
2029  * If one is found it returns true.
2030  */
ipv6_chk_custom_prefix(const struct in6_addr * addr,const unsigned int prefix_len,struct net_device * dev)2031 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
2032 	const unsigned int prefix_len, struct net_device *dev)
2033 {
2034 	const struct inet6_ifaddr *ifa;
2035 	const struct inet6_dev *idev;
2036 	bool ret = false;
2037 
2038 	rcu_read_lock();
2039 	idev = __in6_dev_get(dev);
2040 	if (idev) {
2041 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
2042 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
2043 			if (ret)
2044 				break;
2045 		}
2046 	}
2047 	rcu_read_unlock();
2048 
2049 	return ret;
2050 }
2051 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
2052 
ipv6_chk_prefix(const struct in6_addr * addr,struct net_device * dev)2053 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
2054 {
2055 	const struct inet6_ifaddr *ifa;
2056 	const struct inet6_dev *idev;
2057 	int	onlink;
2058 
2059 	onlink = 0;
2060 	rcu_read_lock();
2061 	idev = __in6_dev_get(dev);
2062 	if (idev) {
2063 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
2064 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
2065 						   ifa->prefix_len);
2066 			if (onlink)
2067 				break;
2068 		}
2069 	}
2070 	rcu_read_unlock();
2071 	return onlink;
2072 }
2073 EXPORT_SYMBOL(ipv6_chk_prefix);
2074 
2075 /**
2076  * ipv6_dev_find - find the first device with a given source address.
2077  * @net: the net namespace
2078  * @addr: the source address
2079  * @dev: used to find the L3 domain of interest
2080  *
2081  * The caller should be protected by RCU, or RTNL.
2082  */
ipv6_dev_find(struct net * net,const struct in6_addr * addr,struct net_device * dev)2083 struct net_device *ipv6_dev_find(struct net *net, const struct in6_addr *addr,
2084 				 struct net_device *dev)
2085 {
2086 	return __ipv6_chk_addr_and_flags(net, addr, dev, !dev, 1,
2087 					 IFA_F_TENTATIVE);
2088 }
2089 EXPORT_SYMBOL(ipv6_dev_find);
2090 
ipv6_get_ifaddr(struct net * net,const struct in6_addr * addr,struct net_device * dev,int strict)2091 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
2092 				     struct net_device *dev, int strict)
2093 {
2094 	unsigned int hash = inet6_addr_hash(net, addr);
2095 	struct inet6_ifaddr *ifp, *result = NULL;
2096 
2097 	rcu_read_lock();
2098 	hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
2099 		if (ipv6_addr_equal(&ifp->addr, addr)) {
2100 			if (!dev || ifp->idev->dev == dev ||
2101 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
2102 				if (in6_ifa_hold_safe(ifp)) {
2103 					result = ifp;
2104 					break;
2105 				}
2106 			}
2107 		}
2108 	}
2109 	rcu_read_unlock();
2110 
2111 	return result;
2112 }
2113 
2114 /* Gets referenced address, destroys ifaddr */
2115 
addrconf_dad_stop(struct inet6_ifaddr * ifp,int dad_failed)2116 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
2117 {
2118 	if (dad_failed)
2119 		ifp->flags |= IFA_F_DADFAILED;
2120 
2121 	if (ifp->flags&IFA_F_TEMPORARY) {
2122 		struct inet6_ifaddr *ifpub;
2123 		spin_lock_bh(&ifp->lock);
2124 		ifpub = ifp->ifpub;
2125 		if (ifpub) {
2126 			in6_ifa_hold(ifpub);
2127 			spin_unlock_bh(&ifp->lock);
2128 			ipv6_create_tempaddr(ifpub, true);
2129 			in6_ifa_put(ifpub);
2130 		} else {
2131 			spin_unlock_bh(&ifp->lock);
2132 		}
2133 		ipv6_del_addr(ifp);
2134 	} else if (ifp->flags&IFA_F_PERMANENT || !dad_failed) {
2135 		spin_lock_bh(&ifp->lock);
2136 		addrconf_del_dad_work(ifp);
2137 		ifp->flags |= IFA_F_TENTATIVE;
2138 		if (dad_failed)
2139 			ifp->flags &= ~IFA_F_OPTIMISTIC;
2140 		spin_unlock_bh(&ifp->lock);
2141 		if (dad_failed)
2142 			ipv6_ifa_notify(0, ifp);
2143 		in6_ifa_put(ifp);
2144 	} else {
2145 		ipv6_del_addr(ifp);
2146 	}
2147 }
2148 
addrconf_dad_end(struct inet6_ifaddr * ifp)2149 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
2150 {
2151 	int err = -ENOENT;
2152 
2153 	spin_lock_bh(&ifp->lock);
2154 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
2155 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
2156 		err = 0;
2157 	}
2158 	spin_unlock_bh(&ifp->lock);
2159 
2160 	return err;
2161 }
2162 
addrconf_dad_failure(struct sk_buff * skb,struct inet6_ifaddr * ifp)2163 void addrconf_dad_failure(struct sk_buff *skb, struct inet6_ifaddr *ifp)
2164 {
2165 	struct inet6_dev *idev = ifp->idev;
2166 	struct net *net = dev_net(idev->dev);
2167 	int max_addresses;
2168 
2169 	if (addrconf_dad_end(ifp)) {
2170 		in6_ifa_put(ifp);
2171 		return;
2172 	}
2173 
2174 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c used by %pM detected!\n",
2175 			     ifp->idev->dev->name, &ifp->addr, eth_hdr(skb)->h_source);
2176 
2177 	spin_lock_bh(&ifp->lock);
2178 
2179 	if (ifp->flags & IFA_F_STABLE_PRIVACY) {
2180 		struct in6_addr new_addr;
2181 		struct inet6_ifaddr *ifp2;
2182 		int retries = ifp->stable_privacy_retry + 1;
2183 		struct ifa6_config cfg = {
2184 			.pfx = &new_addr,
2185 			.plen = ifp->prefix_len,
2186 			.ifa_flags = ifp->flags,
2187 			.valid_lft = ifp->valid_lft,
2188 			.preferred_lft = ifp->prefered_lft,
2189 			.scope = ifp->scope,
2190 		};
2191 
2192 		if (retries > net->ipv6.sysctl.idgen_retries) {
2193 			net_info_ratelimited("%s: privacy stable address generation failed because of DAD conflicts!\n",
2194 					     ifp->idev->dev->name);
2195 			goto errdad;
2196 		}
2197 
2198 		new_addr = ifp->addr;
2199 		if (ipv6_generate_stable_address(&new_addr, retries,
2200 						 idev))
2201 			goto errdad;
2202 
2203 		spin_unlock_bh(&ifp->lock);
2204 
2205 		max_addresses = READ_ONCE(idev->cnf.max_addresses);
2206 		if (max_addresses &&
2207 		    ipv6_count_addresses(idev) >= max_addresses)
2208 			goto lock_errdad;
2209 
2210 		net_info_ratelimited("%s: generating new stable privacy address because of DAD conflict\n",
2211 				     ifp->idev->dev->name);
2212 
2213 		ifp2 = ipv6_add_addr(idev, &cfg, false, NULL);
2214 		if (IS_ERR(ifp2))
2215 			goto lock_errdad;
2216 
2217 		spin_lock_bh(&ifp2->lock);
2218 		ifp2->stable_privacy_retry = retries;
2219 		ifp2->state = INET6_IFADDR_STATE_PREDAD;
2220 		spin_unlock_bh(&ifp2->lock);
2221 
2222 		addrconf_mod_dad_work(ifp2, net->ipv6.sysctl.idgen_delay);
2223 		in6_ifa_put(ifp2);
2224 lock_errdad:
2225 		spin_lock_bh(&ifp->lock);
2226 	}
2227 
2228 errdad:
2229 	/* transition from _POSTDAD to _ERRDAD */
2230 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
2231 	spin_unlock_bh(&ifp->lock);
2232 
2233 	addrconf_mod_dad_work(ifp, 0);
2234 	in6_ifa_put(ifp);
2235 }
2236 
2237 /* Join to solicited addr multicast group. */
addrconf_join_solict(struct net_device * dev,const struct in6_addr * addr)2238 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
2239 {
2240 	struct in6_addr maddr;
2241 
2242 	if (READ_ONCE(dev->flags) & (IFF_LOOPBACK | IFF_NOARP))
2243 		return;
2244 
2245 	addrconf_addr_solict_mult(addr, &maddr);
2246 	ipv6_dev_mc_inc(dev, &maddr);
2247 }
2248 
addrconf_leave_solict(struct inet6_dev * idev,const struct in6_addr * addr)2249 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
2250 {
2251 	struct in6_addr maddr;
2252 
2253 	if (READ_ONCE(idev->dev->flags) & (IFF_LOOPBACK | IFF_NOARP))
2254 		return;
2255 
2256 	addrconf_addr_solict_mult(addr, &maddr);
2257 	__ipv6_dev_mc_dec(idev, &maddr);
2258 }
2259 
addrconf_join_anycast(struct inet6_ifaddr * ifp)2260 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
2261 {
2262 	struct in6_addr addr;
2263 
2264 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2265 		return;
2266 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2267 	if (ipv6_addr_any(&addr))
2268 		return;
2269 	__ipv6_dev_ac_inc(ifp->idev, &addr);
2270 }
2271 
addrconf_leave_anycast(struct inet6_ifaddr * ifp)2272 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
2273 {
2274 	struct in6_addr addr;
2275 
2276 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2277 		return;
2278 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2279 	if (ipv6_addr_any(&addr))
2280 		return;
2281 	__ipv6_dev_ac_dec(ifp->idev, &addr);
2282 }
2283 
addrconf_ifid_6lowpan(u8 * eui,struct net_device * dev)2284 static int addrconf_ifid_6lowpan(u8 *eui, struct net_device *dev)
2285 {
2286 	switch (dev->addr_len) {
2287 	case ETH_ALEN:
2288 		memcpy(eui, dev->dev_addr, 3);
2289 		eui[3] = 0xFF;
2290 		eui[4] = 0xFE;
2291 		memcpy(eui + 5, dev->dev_addr + 3, 3);
2292 		break;
2293 	case EUI64_ADDR_LEN:
2294 		memcpy(eui, dev->dev_addr, EUI64_ADDR_LEN);
2295 		eui[0] ^= 2;
2296 		break;
2297 	default:
2298 		return -1;
2299 	}
2300 
2301 	return 0;
2302 }
2303 
addrconf_ifid_ieee1394(u8 * eui,struct net_device * dev)2304 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
2305 {
2306 	const union fwnet_hwaddr *ha;
2307 
2308 	if (dev->addr_len != FWNET_ALEN)
2309 		return -1;
2310 
2311 	ha = (const union fwnet_hwaddr *)dev->dev_addr;
2312 
2313 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
2314 	eui[0] ^= 2;
2315 	return 0;
2316 }
2317 
addrconf_ifid_arcnet(u8 * eui,struct net_device * dev)2318 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
2319 {
2320 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
2321 	if (dev->addr_len != ARCNET_ALEN)
2322 		return -1;
2323 	memset(eui, 0, 7);
2324 	eui[7] = *(u8 *)dev->dev_addr;
2325 	return 0;
2326 }
2327 
addrconf_ifid_infiniband(u8 * eui,struct net_device * dev)2328 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
2329 {
2330 	if (dev->addr_len != INFINIBAND_ALEN)
2331 		return -1;
2332 	memcpy(eui, dev->dev_addr + 12, 8);
2333 	eui[0] |= 2;
2334 	return 0;
2335 }
2336 
__ipv6_isatap_ifid(u8 * eui,__be32 addr)2337 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
2338 {
2339 	if (addr == 0)
2340 		return -1;
2341 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
2342 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
2343 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
2344 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
2345 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
2346 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
2347 	eui[1] = 0;
2348 	eui[2] = 0x5E;
2349 	eui[3] = 0xFE;
2350 	memcpy(eui + 4, &addr, 4);
2351 	return 0;
2352 }
2353 
addrconf_ifid_sit(u8 * eui,struct net_device * dev)2354 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
2355 {
2356 	if (dev->priv_flags & IFF_ISATAP)
2357 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2358 	return -1;
2359 }
2360 
addrconf_ifid_gre(u8 * eui,struct net_device * dev)2361 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
2362 {
2363 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2364 }
2365 
addrconf_ifid_ip6tnl(u8 * eui,struct net_device * dev)2366 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
2367 {
2368 	memcpy(eui, dev->perm_addr, 3);
2369 	memcpy(eui + 5, dev->perm_addr + 3, 3);
2370 	eui[3] = 0xFF;
2371 	eui[4] = 0xFE;
2372 	eui[0] ^= 2;
2373 	return 0;
2374 }
2375 
ipv6_generate_eui64(u8 * eui,struct net_device * dev)2376 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
2377 {
2378 	switch (dev->type) {
2379 	case ARPHRD_ETHER:
2380 	case ARPHRD_FDDI:
2381 		return addrconf_ifid_eui48(eui, dev);
2382 	case ARPHRD_ARCNET:
2383 		return addrconf_ifid_arcnet(eui, dev);
2384 	case ARPHRD_INFINIBAND:
2385 		return addrconf_ifid_infiniband(eui, dev);
2386 	case ARPHRD_SIT:
2387 		return addrconf_ifid_sit(eui, dev);
2388 	case ARPHRD_IPGRE:
2389 	case ARPHRD_TUNNEL:
2390 		return addrconf_ifid_gre(eui, dev);
2391 	case ARPHRD_6LOWPAN:
2392 		return addrconf_ifid_6lowpan(eui, dev);
2393 	case ARPHRD_IEEE1394:
2394 		return addrconf_ifid_ieee1394(eui, dev);
2395 	case ARPHRD_TUNNEL6:
2396 	case ARPHRD_IP6GRE:
2397 	case ARPHRD_RAWIP:
2398 		return addrconf_ifid_ip6tnl(eui, dev);
2399 	}
2400 	return -1;
2401 }
2402 
ipv6_inherit_eui64(u8 * eui,struct inet6_dev * idev)2403 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
2404 {
2405 	int err = -1;
2406 	struct inet6_ifaddr *ifp;
2407 
2408 	read_lock_bh(&idev->lock);
2409 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
2410 		if (ifp->scope > IFA_LINK)
2411 			break;
2412 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
2413 			memcpy(eui, ifp->addr.s6_addr+8, 8);
2414 			err = 0;
2415 			break;
2416 		}
2417 	}
2418 	read_unlock_bh(&idev->lock);
2419 	return err;
2420 }
2421 
2422 /* Generation of a randomized Interface Identifier
2423  * draft-ietf-6man-rfc4941bis, Section 3.3.1
2424  */
2425 
ipv6_gen_rnd_iid(struct in6_addr * addr)2426 static void ipv6_gen_rnd_iid(struct in6_addr *addr)
2427 {
2428 regen:
2429 	get_random_bytes(&addr->s6_addr[8], 8);
2430 
2431 	/* <draft-ietf-6man-rfc4941bis-08.txt>, Section 3.3.1:
2432 	 * check if generated address is not inappropriate:
2433 	 *
2434 	 * - Reserved IPv6 Interface Identifiers
2435 	 * - XXX: already assigned to an address on the device
2436 	 */
2437 
2438 	/* Subnet-router anycast: 0000:0000:0000:0000 */
2439 	if (!(addr->s6_addr32[2] | addr->s6_addr32[3]))
2440 		goto regen;
2441 
2442 	/* IANA Ethernet block: 0200:5EFF:FE00:0000-0200:5EFF:FE00:5212
2443 	 * Proxy Mobile IPv6:   0200:5EFF:FE00:5213
2444 	 * IANA Ethernet block: 0200:5EFF:FE00:5214-0200:5EFF:FEFF:FFFF
2445 	 */
2446 	if (ntohl(addr->s6_addr32[2]) == 0x02005eff &&
2447 	    (ntohl(addr->s6_addr32[3]) & 0Xff000000) == 0xfe000000)
2448 		goto regen;
2449 
2450 	/* Reserved subnet anycast addresses */
2451 	if (ntohl(addr->s6_addr32[2]) == 0xfdffffff &&
2452 	    ntohl(addr->s6_addr32[3]) >= 0Xffffff80)
2453 		goto regen;
2454 }
2455 
2456 /*
2457  *	Add prefix route.
2458  */
2459 
2460 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)2461 addrconf_prefix_route(struct in6_addr *pfx, int plen, u32 metric,
2462 		      struct net_device *dev, unsigned long expires,
2463 		      u32 flags, gfp_t gfp_flags)
2464 {
2465 	struct fib6_config cfg = {
2466 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX,
2467 		.fc_metric = metric ? : IP6_RT_PRIO_ADDRCONF,
2468 		.fc_ifindex = dev->ifindex,
2469 		.fc_expires = expires,
2470 		.fc_dst_len = plen,
2471 		.fc_flags = RTF_UP | flags,
2472 		.fc_nlinfo.nl_net = dev_net(dev),
2473 		.fc_protocol = RTPROT_KERNEL,
2474 		.fc_type = RTN_UNICAST,
2475 	};
2476 
2477 	cfg.fc_dst = *pfx;
2478 
2479 	/* Prevent useless cloning on PtP SIT.
2480 	   This thing is done here expecting that the whole
2481 	   class of non-broadcast devices need not cloning.
2482 	 */
2483 #if IS_ENABLED(CONFIG_IPV6_SIT)
2484 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2485 		cfg.fc_flags |= RTF_NONEXTHOP;
2486 #endif
2487 
2488 	ip6_route_add(&cfg, gfp_flags, NULL);
2489 }
2490 
2491 
addrconf_get_prefix_route(const struct in6_addr * pfx,int plen,const struct net_device * dev,u32 flags,u32 noflags,bool no_gw)2492 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2493 						  int plen,
2494 						  const struct net_device *dev,
2495 						  u32 flags, u32 noflags,
2496 						  bool no_gw)
2497 {
2498 	struct fib6_node *fn;
2499 	struct fib6_info *rt = NULL;
2500 	struct fib6_table *table;
2501 	u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX;
2502 
2503 	table = fib6_get_table(dev_net(dev), tb_id);
2504 	if (!table)
2505 		return NULL;
2506 
2507 	rcu_read_lock();
2508 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0, true);
2509 	if (!fn)
2510 		goto out;
2511 
2512 	for_each_fib6_node_rt_rcu(fn) {
2513 		/* prefix routes only use builtin fib6_nh */
2514 		if (rt->nh)
2515 			continue;
2516 
2517 		if (rt->fib6_nh->fib_nh_dev->ifindex != dev->ifindex)
2518 			continue;
2519 		if (no_gw && rt->fib6_nh->fib_nh_gw_family)
2520 			continue;
2521 		if ((rt->fib6_flags & flags) != flags)
2522 			continue;
2523 		if ((rt->fib6_flags & noflags) != 0)
2524 			continue;
2525 		if (!fib6_info_hold_safe(rt))
2526 			continue;
2527 		break;
2528 	}
2529 out:
2530 	rcu_read_unlock();
2531 	return rt;
2532 }
2533 
2534 
2535 /* Create "default" multicast route to the interface */
2536 
addrconf_add_mroute(struct net_device * dev)2537 static void addrconf_add_mroute(struct net_device *dev)
2538 {
2539 	struct fib6_config cfg = {
2540 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_LOCAL,
2541 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2542 		.fc_ifindex = dev->ifindex,
2543 		.fc_dst_len = 8,
2544 		.fc_flags = RTF_UP,
2545 		.fc_type = RTN_MULTICAST,
2546 		.fc_nlinfo.nl_net = dev_net(dev),
2547 		.fc_protocol = RTPROT_KERNEL,
2548 	};
2549 
2550 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2551 
2552 	ip6_route_add(&cfg, GFP_KERNEL, NULL);
2553 }
2554 
addrconf_add_dev(struct net_device * dev)2555 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2556 {
2557 	struct inet6_dev *idev;
2558 
2559 	ASSERT_RTNL();
2560 
2561 	idev = ipv6_find_idev(dev);
2562 	if (IS_ERR(idev))
2563 		return idev;
2564 
2565 	if (idev->cnf.disable_ipv6)
2566 		return ERR_PTR(-EACCES);
2567 
2568 	/* Add default multicast route */
2569 	if (!(dev->flags & IFF_LOOPBACK) && !netif_is_l3_master(dev))
2570 		addrconf_add_mroute(dev);
2571 
2572 	return idev;
2573 }
2574 
delete_tempaddrs(struct inet6_dev * idev,struct inet6_ifaddr * ifp)2575 static void delete_tempaddrs(struct inet6_dev *idev,
2576 			     struct inet6_ifaddr *ifp)
2577 {
2578 	struct inet6_ifaddr *ift, *tmp;
2579 
2580 	write_lock_bh(&idev->lock);
2581 	list_for_each_entry_safe(ift, tmp, &idev->tempaddr_list, tmp_list) {
2582 		if (ift->ifpub != ifp)
2583 			continue;
2584 
2585 		in6_ifa_hold(ift);
2586 		write_unlock_bh(&idev->lock);
2587 		ipv6_del_addr(ift);
2588 		write_lock_bh(&idev->lock);
2589 	}
2590 	write_unlock_bh(&idev->lock);
2591 }
2592 
manage_tempaddrs(struct inet6_dev * idev,struct inet6_ifaddr * ifp,__u32 valid_lft,__u32 prefered_lft,bool create,unsigned long now)2593 static void manage_tempaddrs(struct inet6_dev *idev,
2594 			     struct inet6_ifaddr *ifp,
2595 			     __u32 valid_lft, __u32 prefered_lft,
2596 			     bool create, unsigned long now)
2597 {
2598 	u32 flags;
2599 	struct inet6_ifaddr *ift;
2600 
2601 	read_lock_bh(&idev->lock);
2602 	/* update all temporary addresses in the list */
2603 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2604 		int age, max_valid, max_prefered;
2605 
2606 		if (ifp != ift->ifpub)
2607 			continue;
2608 
2609 		/* RFC 4941 section 3.3:
2610 		 * If a received option will extend the lifetime of a public
2611 		 * address, the lifetimes of temporary addresses should
2612 		 * be extended, subject to the overall constraint that no
2613 		 * temporary addresses should ever remain "valid" or "preferred"
2614 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2615 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2616 		 */
2617 		age = (now - ift->cstamp) / HZ;
2618 		max_valid = READ_ONCE(idev->cnf.temp_valid_lft) - age;
2619 		if (max_valid < 0)
2620 			max_valid = 0;
2621 
2622 		max_prefered = READ_ONCE(idev->cnf.temp_prefered_lft) -
2623 			       idev->desync_factor - age;
2624 		if (max_prefered < 0)
2625 			max_prefered = 0;
2626 
2627 		if (valid_lft > max_valid)
2628 			valid_lft = max_valid;
2629 
2630 		if (prefered_lft > max_prefered)
2631 			prefered_lft = max_prefered;
2632 
2633 		spin_lock(&ift->lock);
2634 		flags = ift->flags;
2635 		ift->valid_lft = valid_lft;
2636 		ift->prefered_lft = prefered_lft;
2637 		ift->tstamp = now;
2638 		if (prefered_lft > 0)
2639 			ift->flags &= ~IFA_F_DEPRECATED;
2640 
2641 		spin_unlock(&ift->lock);
2642 		if (!(flags&IFA_F_TENTATIVE))
2643 			ipv6_ifa_notify(0, ift);
2644 	}
2645 
2646 	/* Also create a temporary address if it's enabled but no temporary
2647 	 * address currently exists.
2648 	 * However, we get called with valid_lft == 0, prefered_lft == 0, create == false
2649 	 * as part of cleanup (ie. deleting the mngtmpaddr).
2650 	 * We don't want that to result in creating a new temporary ip address.
2651 	 */
2652 	if (list_empty(&idev->tempaddr_list) && (valid_lft || prefered_lft))
2653 		create = true;
2654 
2655 	if (create && READ_ONCE(idev->cnf.use_tempaddr) > 0) {
2656 		/* When a new public address is created as described
2657 		 * in [ADDRCONF], also create a new temporary address.
2658 		 */
2659 		read_unlock_bh(&idev->lock);
2660 		ipv6_create_tempaddr(ifp, false);
2661 	} else {
2662 		read_unlock_bh(&idev->lock);
2663 	}
2664 }
2665 
is_addr_mode_generate_stable(struct inet6_dev * idev)2666 static bool is_addr_mode_generate_stable(struct inet6_dev *idev)
2667 {
2668 	return idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY ||
2669 	       idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_RANDOM;
2670 }
2671 
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)2672 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
2673 				 const struct prefix_info *pinfo,
2674 				 struct inet6_dev *in6_dev,
2675 				 const struct in6_addr *addr, int addr_type,
2676 				 u32 addr_flags, bool sllao, bool tokenized,
2677 				 __u32 valid_lft, u32 prefered_lft)
2678 {
2679 	struct inet6_ifaddr *ifp = ipv6_get_ifaddr(net, addr, dev, 1);
2680 	int create = 0, update_lft = 0;
2681 
2682 	if (!ifp && valid_lft) {
2683 		int max_addresses = READ_ONCE(in6_dev->cnf.max_addresses);
2684 		struct ifa6_config cfg = {
2685 			.pfx = addr,
2686 			.plen = pinfo->prefix_len,
2687 			.ifa_flags = addr_flags,
2688 			.valid_lft = valid_lft,
2689 			.preferred_lft = prefered_lft,
2690 			.scope = addr_type & IPV6_ADDR_SCOPE_MASK,
2691 			.ifa_proto = IFAPROT_KERNEL_RA
2692 		};
2693 
2694 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2695 		if ((READ_ONCE(net->ipv6.devconf_all->optimistic_dad) ||
2696 		     READ_ONCE(in6_dev->cnf.optimistic_dad)) &&
2697 		    !net->ipv6.devconf_all->forwarding && sllao)
2698 			cfg.ifa_flags |= IFA_F_OPTIMISTIC;
2699 #endif
2700 
2701 		/* Do not allow to create too much of autoconfigured
2702 		 * addresses; this would be too easy way to crash kernel.
2703 		 */
2704 		if (!max_addresses ||
2705 		    ipv6_count_addresses(in6_dev) < max_addresses)
2706 			ifp = ipv6_add_addr(in6_dev, &cfg, false, NULL);
2707 
2708 		if (IS_ERR_OR_NULL(ifp))
2709 			return -1;
2710 
2711 		create = 1;
2712 		spin_lock_bh(&ifp->lock);
2713 		ifp->flags |= IFA_F_MANAGETEMPADDR;
2714 		ifp->cstamp = jiffies;
2715 		ifp->tokenized = tokenized;
2716 		spin_unlock_bh(&ifp->lock);
2717 		addrconf_dad_start(ifp);
2718 	}
2719 
2720 	if (ifp) {
2721 		u32 flags;
2722 		unsigned long now;
2723 		u32 stored_lft;
2724 
2725 		/* update lifetime (RFC2462 5.5.3 e) */
2726 		spin_lock_bh(&ifp->lock);
2727 		now = jiffies;
2728 		if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2729 			stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2730 		else
2731 			stored_lft = 0;
2732 
2733 		/* RFC4862 Section 5.5.3e:
2734 		 * "Note that the preferred lifetime of the
2735 		 *  corresponding address is always reset to
2736 		 *  the Preferred Lifetime in the received
2737 		 *  Prefix Information option, regardless of
2738 		 *  whether the valid lifetime is also reset or
2739 		 *  ignored."
2740 		 *
2741 		 * So we should always update prefered_lft here.
2742 		 */
2743 		update_lft = !create && stored_lft;
2744 
2745 		if (update_lft && !READ_ONCE(in6_dev->cnf.ra_honor_pio_life)) {
2746 			const u32 minimum_lft = min_t(u32,
2747 				stored_lft, MIN_VALID_LIFETIME);
2748 			valid_lft = max(valid_lft, minimum_lft);
2749 		}
2750 
2751 		if (update_lft) {
2752 			ifp->valid_lft = valid_lft;
2753 			ifp->prefered_lft = prefered_lft;
2754 			WRITE_ONCE(ifp->tstamp, now);
2755 			flags = ifp->flags;
2756 			ifp->flags &= ~IFA_F_DEPRECATED;
2757 			spin_unlock_bh(&ifp->lock);
2758 
2759 			if (!(flags&IFA_F_TENTATIVE))
2760 				ipv6_ifa_notify(0, ifp);
2761 		} else
2762 			spin_unlock_bh(&ifp->lock);
2763 
2764 		manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2765 				 create, now);
2766 
2767 		in6_ifa_put(ifp);
2768 		addrconf_verify(net);
2769 	}
2770 
2771 	return 0;
2772 }
2773 EXPORT_SYMBOL_GPL(addrconf_prefix_rcv_add_addr);
2774 
addrconf_prefix_rcv(struct net_device * dev,u8 * opt,int len,bool sllao)2775 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2776 {
2777 	struct prefix_info *pinfo;
2778 	struct fib6_table *table;
2779 	__u32 valid_lft;
2780 	__u32 prefered_lft;
2781 	int addr_type, err;
2782 	u32 addr_flags = 0;
2783 	struct inet6_dev *in6_dev;
2784 	struct net *net = dev_net(dev);
2785 	bool ignore_autoconf = false;
2786 
2787 	pinfo = (struct prefix_info *) opt;
2788 
2789 	if (len < sizeof(struct prefix_info)) {
2790 		netdev_dbg(dev, "addrconf: prefix option too short\n");
2791 		return;
2792 	}
2793 
2794 	/*
2795 	 *	Validation checks ([ADDRCONF], page 19)
2796 	 */
2797 
2798 	addr_type = ipv6_addr_type(&pinfo->prefix);
2799 
2800 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2801 		return;
2802 
2803 	valid_lft = ntohl(pinfo->valid);
2804 	prefered_lft = ntohl(pinfo->prefered);
2805 
2806 	if (prefered_lft > valid_lft) {
2807 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2808 		return;
2809 	}
2810 
2811 	in6_dev = in6_dev_get(dev);
2812 
2813 	if (!in6_dev) {
2814 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2815 				    dev->name);
2816 		return;
2817 	}
2818 
2819 	if (valid_lft != 0 && valid_lft < in6_dev->cnf.accept_ra_min_lft)
2820 		goto put;
2821 
2822 	/*
2823 	 *	Two things going on here:
2824 	 *	1) Add routes for on-link prefixes
2825 	 *	2) Configure prefixes with the auto flag set
2826 	 */
2827 
2828 	if (pinfo->onlink) {
2829 		struct fib6_info *rt;
2830 		unsigned long rt_expires;
2831 
2832 		/* Avoid arithmetic overflow. Really, we could
2833 		 * save rt_expires in seconds, likely valid_lft,
2834 		 * but it would require division in fib gc, that it
2835 		 * not good.
2836 		 */
2837 		if (HZ > USER_HZ)
2838 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2839 		else
2840 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2841 
2842 		if (addrconf_finite_timeout(rt_expires))
2843 			rt_expires *= HZ;
2844 
2845 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2846 					       pinfo->prefix_len,
2847 					       dev,
2848 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2849 					       RTF_DEFAULT, true);
2850 
2851 		if (rt) {
2852 			/* Autoconf prefix route */
2853 			if (valid_lft == 0) {
2854 				ip6_del_rt(net, rt, false);
2855 				rt = NULL;
2856 			} else {
2857 				table = rt->fib6_table;
2858 				spin_lock_bh(&table->tb6_lock);
2859 
2860 				if (addrconf_finite_timeout(rt_expires)) {
2861 					/* not infinity */
2862 					fib6_set_expires(rt, jiffies + rt_expires);
2863 					fib6_add_gc_list(rt);
2864 				} else {
2865 					fib6_clean_expires(rt);
2866 					fib6_remove_gc_list(rt);
2867 				}
2868 
2869 				spin_unlock_bh(&table->tb6_lock);
2870 			}
2871 		} else if (valid_lft) {
2872 			clock_t expires = 0;
2873 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2874 			if (addrconf_finite_timeout(rt_expires)) {
2875 				/* not infinity */
2876 				flags |= RTF_EXPIRES;
2877 				expires = jiffies_to_clock_t(rt_expires);
2878 			}
2879 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2880 					      0, dev, expires, flags,
2881 					      GFP_ATOMIC);
2882 		}
2883 		fib6_info_release(rt);
2884 	}
2885 
2886 	/* Try to figure out our local address for this prefix */
2887 
2888 	ignore_autoconf = READ_ONCE(in6_dev->cnf.ra_honor_pio_pflag) && pinfo->preferpd;
2889 	if (pinfo->autoconf && in6_dev->cnf.autoconf && !ignore_autoconf) {
2890 		struct in6_addr addr;
2891 		bool tokenized = false, dev_addr_generated = false;
2892 
2893 		if (pinfo->prefix_len == 64) {
2894 			memcpy(&addr, &pinfo->prefix, 8);
2895 
2896 			if (!ipv6_addr_any(&in6_dev->token)) {
2897 				read_lock_bh(&in6_dev->lock);
2898 				memcpy(addr.s6_addr + 8,
2899 				       in6_dev->token.s6_addr + 8, 8);
2900 				read_unlock_bh(&in6_dev->lock);
2901 				tokenized = true;
2902 			} else if (is_addr_mode_generate_stable(in6_dev) &&
2903 				   !ipv6_generate_stable_address(&addr, 0,
2904 								 in6_dev)) {
2905 				addr_flags |= IFA_F_STABLE_PRIVACY;
2906 				goto ok;
2907 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2908 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2909 				goto put;
2910 			} else {
2911 				dev_addr_generated = true;
2912 			}
2913 			goto ok;
2914 		}
2915 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2916 				    pinfo->prefix_len);
2917 		goto put;
2918 
2919 ok:
2920 		err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
2921 						   &addr, addr_type,
2922 						   addr_flags, sllao,
2923 						   tokenized, valid_lft,
2924 						   prefered_lft);
2925 		if (err)
2926 			goto put;
2927 
2928 		/* Ignore error case here because previous prefix add addr was
2929 		 * successful which will be notified.
2930 		 */
2931 		ndisc_ops_prefix_rcv_add_addr(net, dev, pinfo, in6_dev, &addr,
2932 					      addr_type, addr_flags, sllao,
2933 					      tokenized, valid_lft,
2934 					      prefered_lft,
2935 					      dev_addr_generated);
2936 	}
2937 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2938 put:
2939 	in6_dev_put(in6_dev);
2940 }
2941 
addrconf_set_sit_dstaddr(struct net * net,struct net_device * dev,struct in6_ifreq * ireq)2942 static int addrconf_set_sit_dstaddr(struct net *net, struct net_device *dev,
2943 		struct in6_ifreq *ireq)
2944 {
2945 	struct ip_tunnel_parm_kern p = { };
2946 	int err;
2947 
2948 	if (!(ipv6_addr_type(&ireq->ifr6_addr) & IPV6_ADDR_COMPATv4))
2949 		return -EADDRNOTAVAIL;
2950 
2951 	p.iph.daddr = ireq->ifr6_addr.s6_addr32[3];
2952 	p.iph.version = 4;
2953 	p.iph.ihl = 5;
2954 	p.iph.protocol = IPPROTO_IPV6;
2955 	p.iph.ttl = 64;
2956 
2957 	if (!dev->netdev_ops->ndo_tunnel_ctl)
2958 		return -EOPNOTSUPP;
2959 	err = dev->netdev_ops->ndo_tunnel_ctl(dev, &p, SIOCADDTUNNEL);
2960 	if (err)
2961 		return err;
2962 
2963 	dev = __dev_get_by_name(net, p.name);
2964 	if (!dev)
2965 		return -ENOBUFS;
2966 	return dev_open(dev, NULL);
2967 }
2968 
2969 /*
2970  *	Set destination address.
2971  *	Special case for SIT interfaces where we create a new "virtual"
2972  *	device.
2973  */
addrconf_set_dstaddr(struct net * net,void __user * arg)2974 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2975 {
2976 	struct net_device *dev;
2977 	struct in6_ifreq ireq;
2978 	int err = -ENODEV;
2979 
2980 	if (!IS_ENABLED(CONFIG_IPV6_SIT))
2981 		return -ENODEV;
2982 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2983 		return -EFAULT;
2984 
2985 	rtnl_net_lock(net);
2986 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2987 	if (dev && dev->type == ARPHRD_SIT)
2988 		err = addrconf_set_sit_dstaddr(net, dev, &ireq);
2989 	rtnl_net_unlock(net);
2990 	return err;
2991 }
2992 
ipv6_mc_config(struct sock * sk,bool join,const struct in6_addr * addr,int ifindex)2993 static int ipv6_mc_config(struct sock *sk, bool join,
2994 			  const struct in6_addr *addr, int ifindex)
2995 {
2996 	int ret;
2997 
2998 	ASSERT_RTNL();
2999 
3000 	lock_sock(sk);
3001 	if (join)
3002 		ret = ipv6_sock_mc_join(sk, ifindex, addr);
3003 	else
3004 		ret = ipv6_sock_mc_drop(sk, ifindex, addr);
3005 	release_sock(sk);
3006 
3007 	return ret;
3008 }
3009 
3010 /*
3011  *	Manual configuration of address on an interface
3012  */
inet6_addr_add(struct net * net,struct net_device * dev,struct ifa6_config * cfg,clock_t expires,u32 flags,struct netlink_ext_ack * extack)3013 static int inet6_addr_add(struct net *net, struct net_device *dev,
3014 			  struct ifa6_config *cfg, clock_t expires, u32 flags,
3015 			  struct netlink_ext_ack *extack)
3016 {
3017 	struct inet6_ifaddr *ifp;
3018 	struct inet6_dev *idev;
3019 
3020 	ASSERT_RTNL_NET(net);
3021 
3022 	if (cfg->plen > 128) {
3023 		NL_SET_ERR_MSG_MOD(extack, "Invalid prefix length");
3024 		return -EINVAL;
3025 	}
3026 
3027 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR && cfg->plen != 64) {
3028 		NL_SET_ERR_MSG_MOD(extack, "address with \"mngtmpaddr\" flag must have a prefix length of 64");
3029 		return -EINVAL;
3030 	}
3031 
3032 	idev = addrconf_add_dev(dev);
3033 	if (IS_ERR(idev)) {
3034 		NL_SET_ERR_MSG_MOD(extack, "IPv6 is disabled on this device");
3035 		return PTR_ERR(idev);
3036 	}
3037 
3038 	if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
3039 		int ret = ipv6_mc_config(net->ipv6.mc_autojoin_sk,
3040 					 true, cfg->pfx, dev->ifindex);
3041 
3042 		if (ret < 0) {
3043 			NL_SET_ERR_MSG_MOD(extack, "Multicast auto join failed");
3044 			return ret;
3045 		}
3046 	}
3047 
3048 	cfg->scope = ipv6_addr_scope(cfg->pfx);
3049 
3050 	ifp = ipv6_add_addr(idev, cfg, true, extack);
3051 	if (!IS_ERR(ifp)) {
3052 		if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
3053 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3054 					      ifp->rt_priority, dev, expires,
3055 					      flags, GFP_KERNEL);
3056 		}
3057 
3058 		/* Send a netlink notification if DAD is enabled and
3059 		 * optimistic flag is not set
3060 		 */
3061 		if (!(ifp->flags & (IFA_F_OPTIMISTIC | IFA_F_NODAD)))
3062 			ipv6_ifa_notify(0, ifp);
3063 		/*
3064 		 * Note that section 3.1 of RFC 4429 indicates
3065 		 * that the Optimistic flag should not be set for
3066 		 * manually configured addresses
3067 		 */
3068 		addrconf_dad_start(ifp);
3069 		if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR)
3070 			manage_tempaddrs(idev, ifp, cfg->valid_lft,
3071 					 cfg->preferred_lft, true, jiffies);
3072 		in6_ifa_put(ifp);
3073 		addrconf_verify_rtnl(net);
3074 		return 0;
3075 	} else if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
3076 		ipv6_mc_config(net->ipv6.mc_autojoin_sk, false,
3077 			       cfg->pfx, dev->ifindex);
3078 	}
3079 
3080 	return PTR_ERR(ifp);
3081 }
3082 
inet6_addr_del(struct net * net,int ifindex,u32 ifa_flags,const struct in6_addr * pfx,unsigned int plen,struct netlink_ext_ack * extack)3083 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
3084 			  const struct in6_addr *pfx, unsigned int plen,
3085 			  struct netlink_ext_ack *extack)
3086 {
3087 	struct inet6_ifaddr *ifp;
3088 	struct inet6_dev *idev;
3089 	struct net_device *dev;
3090 
3091 	if (plen > 128) {
3092 		NL_SET_ERR_MSG_MOD(extack, "Invalid prefix length");
3093 		return -EINVAL;
3094 	}
3095 
3096 	dev = __dev_get_by_index(net, ifindex);
3097 	if (!dev) {
3098 		NL_SET_ERR_MSG_MOD(extack, "Unable to find the interface");
3099 		return -ENODEV;
3100 	}
3101 
3102 	idev = __in6_dev_get_rtnl_net(dev);
3103 	if (!idev) {
3104 		NL_SET_ERR_MSG_MOD(extack, "IPv6 is disabled on this device");
3105 		return -ENXIO;
3106 	}
3107 
3108 	read_lock_bh(&idev->lock);
3109 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
3110 		if (ifp->prefix_len == plen &&
3111 		    ipv6_addr_equal(pfx, &ifp->addr)) {
3112 			in6_ifa_hold(ifp);
3113 			read_unlock_bh(&idev->lock);
3114 
3115 			ipv6_del_addr(ifp);
3116 
3117 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
3118 			    (ifp->flags & IFA_F_MANAGETEMPADDR))
3119 				delete_tempaddrs(idev, ifp);
3120 
3121 			addrconf_verify_rtnl(net);
3122 			if (ipv6_addr_is_multicast(pfx)) {
3123 				ipv6_mc_config(net->ipv6.mc_autojoin_sk,
3124 					       false, pfx, dev->ifindex);
3125 			}
3126 			return 0;
3127 		}
3128 	}
3129 	read_unlock_bh(&idev->lock);
3130 
3131 	NL_SET_ERR_MSG_MOD(extack, "address not found");
3132 	return -EADDRNOTAVAIL;
3133 }
3134 
3135 
addrconf_add_ifaddr(struct net * net,void __user * arg)3136 int addrconf_add_ifaddr(struct net *net, void __user *arg)
3137 {
3138 	struct ifa6_config cfg = {
3139 		.ifa_flags = IFA_F_PERMANENT,
3140 		.preferred_lft = INFINITY_LIFE_TIME,
3141 		.valid_lft = INFINITY_LIFE_TIME,
3142 	};
3143 	struct net_device *dev;
3144 	struct in6_ifreq ireq;
3145 	int err;
3146 
3147 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3148 		return -EPERM;
3149 
3150 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3151 		return -EFAULT;
3152 
3153 	cfg.pfx = &ireq.ifr6_addr;
3154 	cfg.plen = ireq.ifr6_prefixlen;
3155 
3156 	rtnl_net_lock(net);
3157 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
3158 	if (dev) {
3159 		netdev_lock_ops(dev);
3160 		err = inet6_addr_add(net, dev, &cfg, 0, 0, NULL);
3161 		netdev_unlock_ops(dev);
3162 	} else {
3163 		err = -ENODEV;
3164 	}
3165 	rtnl_net_unlock(net);
3166 	return err;
3167 }
3168 
addrconf_del_ifaddr(struct net * net,void __user * arg)3169 int addrconf_del_ifaddr(struct net *net, void __user *arg)
3170 {
3171 	struct in6_ifreq ireq;
3172 	int err;
3173 
3174 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3175 		return -EPERM;
3176 
3177 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3178 		return -EFAULT;
3179 
3180 	rtnl_net_lock(net);
3181 	err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
3182 			     ireq.ifr6_prefixlen, NULL);
3183 	rtnl_net_unlock(net);
3184 	return err;
3185 }
3186 
add_addr(struct inet6_dev * idev,const struct in6_addr * addr,int plen,int scope,u8 proto)3187 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
3188 		     int plen, int scope, u8 proto)
3189 {
3190 	struct inet6_ifaddr *ifp;
3191 	struct ifa6_config cfg = {
3192 		.pfx = addr,
3193 		.plen = plen,
3194 		.ifa_flags = IFA_F_PERMANENT,
3195 		.valid_lft = INFINITY_LIFE_TIME,
3196 		.preferred_lft = INFINITY_LIFE_TIME,
3197 		.scope = scope,
3198 		.ifa_proto = proto
3199 	};
3200 
3201 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3202 	if (!IS_ERR(ifp)) {
3203 		spin_lock_bh(&ifp->lock);
3204 		ifp->flags &= ~IFA_F_TENTATIVE;
3205 		spin_unlock_bh(&ifp->lock);
3206 		rt_genid_bump_ipv6(dev_net(idev->dev));
3207 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3208 		in6_ifa_put(ifp);
3209 	}
3210 }
3211 
3212 #if IS_ENABLED(CONFIG_IPV6_SIT) || IS_ENABLED(CONFIG_NET_IPGRE)
add_v4_addrs(struct inet6_dev * idev)3213 static void add_v4_addrs(struct inet6_dev *idev)
3214 {
3215 	struct in6_addr addr;
3216 	struct net_device *dev;
3217 	struct net *net = dev_net(idev->dev);
3218 	int scope, plen;
3219 	u32 pflags = 0;
3220 
3221 	ASSERT_RTNL();
3222 
3223 	memset(&addr, 0, sizeof(struct in6_addr));
3224 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
3225 
3226 	if (!(idev->dev->flags & IFF_POINTOPOINT) && idev->dev->type == ARPHRD_SIT) {
3227 		scope = IPV6_ADDR_COMPATv4;
3228 		plen = 96;
3229 		pflags |= RTF_NONEXTHOP;
3230 	} else {
3231 		if (idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_NONE)
3232 			return;
3233 
3234 		addr.s6_addr32[0] = htonl(0xfe800000);
3235 		scope = IFA_LINK;
3236 		plen = 64;
3237 	}
3238 
3239 	if (addr.s6_addr32[3]) {
3240 		add_addr(idev, &addr, plen, scope, IFAPROT_UNSPEC);
3241 		addrconf_prefix_route(&addr, plen, 0, idev->dev, 0, pflags,
3242 				      GFP_KERNEL);
3243 		return;
3244 	}
3245 
3246 	for_each_netdev(net, dev) {
3247 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
3248 		if (in_dev && (dev->flags & IFF_UP)) {
3249 			struct in_ifaddr *ifa;
3250 			int flag = scope;
3251 
3252 			in_dev_for_each_ifa_rtnl(ifa, in_dev) {
3253 				addr.s6_addr32[3] = ifa->ifa_local;
3254 
3255 				if (ifa->ifa_scope == RT_SCOPE_LINK)
3256 					continue;
3257 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
3258 					if (idev->dev->flags&IFF_POINTOPOINT)
3259 						continue;
3260 					flag |= IFA_HOST;
3261 				}
3262 
3263 				add_addr(idev, &addr, plen, flag,
3264 					 IFAPROT_UNSPEC);
3265 				addrconf_prefix_route(&addr, plen, 0, idev->dev,
3266 						      0, pflags, GFP_KERNEL);
3267 			}
3268 		}
3269 	}
3270 }
3271 #endif
3272 
init_loopback(struct net_device * dev)3273 static void init_loopback(struct net_device *dev)
3274 {
3275 	struct inet6_dev  *idev;
3276 
3277 	/* ::1 */
3278 
3279 	ASSERT_RTNL();
3280 
3281 	idev = ipv6_find_idev(dev);
3282 	if (IS_ERR(idev)) {
3283 		pr_debug("%s: add_dev failed\n", __func__);
3284 		return;
3285 	}
3286 
3287 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST, IFAPROT_KERNEL_LO);
3288 }
3289 
addrconf_add_linklocal(struct inet6_dev * idev,const struct in6_addr * addr,u32 flags)3290 void addrconf_add_linklocal(struct inet6_dev *idev,
3291 			    const struct in6_addr *addr, u32 flags)
3292 {
3293 	struct ifa6_config cfg = {
3294 		.pfx = addr,
3295 		.plen = 64,
3296 		.ifa_flags = flags | IFA_F_PERMANENT,
3297 		.valid_lft = INFINITY_LIFE_TIME,
3298 		.preferred_lft = INFINITY_LIFE_TIME,
3299 		.scope = IFA_LINK,
3300 		.ifa_proto = IFAPROT_KERNEL_LL
3301 	};
3302 	struct inet6_ifaddr *ifp;
3303 
3304 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
3305 	if ((READ_ONCE(dev_net(idev->dev)->ipv6.devconf_all->optimistic_dad) ||
3306 	     READ_ONCE(idev->cnf.optimistic_dad)) &&
3307 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
3308 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
3309 #endif
3310 
3311 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3312 	if (!IS_ERR(ifp)) {
3313 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, 0, idev->dev,
3314 				      0, 0, GFP_ATOMIC);
3315 		addrconf_dad_start(ifp);
3316 		in6_ifa_put(ifp);
3317 	}
3318 }
3319 EXPORT_SYMBOL_GPL(addrconf_add_linklocal);
3320 
ipv6_reserved_interfaceid(struct in6_addr address)3321 static bool ipv6_reserved_interfaceid(struct in6_addr address)
3322 {
3323 	if ((address.s6_addr32[2] | address.s6_addr32[3]) == 0)
3324 		return true;
3325 
3326 	if (address.s6_addr32[2] == htonl(0x02005eff) &&
3327 	    ((address.s6_addr32[3] & htonl(0xfe000000)) == htonl(0xfe000000)))
3328 		return true;
3329 
3330 	if (address.s6_addr32[2] == htonl(0xfdffffff) &&
3331 	    ((address.s6_addr32[3] & htonl(0xffffff80)) == htonl(0xffffff80)))
3332 		return true;
3333 
3334 	return false;
3335 }
3336 
ipv6_generate_stable_address(struct in6_addr * address,u8 dad_count,const struct inet6_dev * idev)3337 static int ipv6_generate_stable_address(struct in6_addr *address,
3338 					u8 dad_count,
3339 					const struct inet6_dev *idev)
3340 {
3341 	static DEFINE_SPINLOCK(lock);
3342 	static __u32 digest[SHA1_DIGEST_WORDS];
3343 	static __u32 workspace[SHA1_WORKSPACE_WORDS];
3344 
3345 	static union {
3346 		char __data[SHA1_BLOCK_SIZE];
3347 		struct {
3348 			struct in6_addr secret;
3349 			__be32 prefix[2];
3350 			unsigned char hwaddr[MAX_ADDR_LEN];
3351 			u8 dad_count;
3352 		} __packed;
3353 	} data;
3354 
3355 	struct in6_addr secret;
3356 	struct in6_addr temp;
3357 	struct net *net = dev_net(idev->dev);
3358 
3359 	BUILD_BUG_ON(sizeof(data.__data) != sizeof(data));
3360 
3361 	if (idev->cnf.stable_secret.initialized)
3362 		secret = idev->cnf.stable_secret.secret;
3363 	else if (net->ipv6.devconf_dflt->stable_secret.initialized)
3364 		secret = net->ipv6.devconf_dflt->stable_secret.secret;
3365 	else
3366 		return -1;
3367 
3368 retry:
3369 	spin_lock_bh(&lock);
3370 
3371 	sha1_init_raw(digest);
3372 	memset(&data, 0, sizeof(data));
3373 	memset(workspace, 0, sizeof(workspace));
3374 	memcpy(data.hwaddr, idev->dev->perm_addr, idev->dev->addr_len);
3375 	data.prefix[0] = address->s6_addr32[0];
3376 	data.prefix[1] = address->s6_addr32[1];
3377 	data.secret = secret;
3378 	data.dad_count = dad_count;
3379 
3380 	sha1_transform(digest, data.__data, workspace);
3381 
3382 	temp = *address;
3383 	temp.s6_addr32[2] = (__force __be32)digest[0];
3384 	temp.s6_addr32[3] = (__force __be32)digest[1];
3385 
3386 	spin_unlock_bh(&lock);
3387 
3388 	if (ipv6_reserved_interfaceid(temp)) {
3389 		dad_count++;
3390 		if (dad_count > dev_net(idev->dev)->ipv6.sysctl.idgen_retries)
3391 			return -1;
3392 		goto retry;
3393 	}
3394 
3395 	*address = temp;
3396 	return 0;
3397 }
3398 
ipv6_gen_mode_random_init(struct inet6_dev * idev)3399 static void ipv6_gen_mode_random_init(struct inet6_dev *idev)
3400 {
3401 	struct ipv6_stable_secret *s = &idev->cnf.stable_secret;
3402 
3403 	if (s->initialized)
3404 		return;
3405 	s = &idev->cnf.stable_secret;
3406 	get_random_bytes(&s->secret, sizeof(s->secret));
3407 	s->initialized = true;
3408 }
3409 
addrconf_addr_gen(struct inet6_dev * idev,bool prefix_route)3410 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
3411 {
3412 	struct in6_addr addr;
3413 
3414 	/* no link local addresses on L3 master devices */
3415 	if (netif_is_l3_master(idev->dev))
3416 		return;
3417 
3418 	/* no link local addresses on devices flagged as slaves */
3419 	if (idev->dev->priv_flags & IFF_NO_ADDRCONF)
3420 		return;
3421 
3422 	ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
3423 
3424 	switch (idev->cnf.addr_gen_mode) {
3425 	case IN6_ADDR_GEN_MODE_RANDOM:
3426 		ipv6_gen_mode_random_init(idev);
3427 		fallthrough;
3428 	case IN6_ADDR_GEN_MODE_STABLE_PRIVACY:
3429 		if (!ipv6_generate_stable_address(&addr, 0, idev))
3430 			addrconf_add_linklocal(idev, &addr,
3431 					       IFA_F_STABLE_PRIVACY);
3432 		else if (prefix_route)
3433 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3434 					      0, 0, GFP_KERNEL);
3435 		break;
3436 	case IN6_ADDR_GEN_MODE_EUI64:
3437 		/* addrconf_add_linklocal also adds a prefix_route and we
3438 		 * only need to care about prefix routes if ipv6_generate_eui64
3439 		 * couldn't generate one.
3440 		 */
3441 		if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
3442 			addrconf_add_linklocal(idev, &addr, 0);
3443 		else if (prefix_route)
3444 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3445 					      0, 0, GFP_KERNEL);
3446 		break;
3447 	case IN6_ADDR_GEN_MODE_NONE:
3448 	default:
3449 		/* will not add any link local address */
3450 		break;
3451 	}
3452 }
3453 
addrconf_dev_config(struct net_device * dev)3454 static void addrconf_dev_config(struct net_device *dev)
3455 {
3456 	struct inet6_dev *idev;
3457 
3458 	ASSERT_RTNL();
3459 
3460 	if ((dev->type != ARPHRD_ETHER) &&
3461 	    (dev->type != ARPHRD_FDDI) &&
3462 	    (dev->type != ARPHRD_ARCNET) &&
3463 	    (dev->type != ARPHRD_INFINIBAND) &&
3464 	    (dev->type != ARPHRD_IEEE1394) &&
3465 	    (dev->type != ARPHRD_TUNNEL6) &&
3466 	    (dev->type != ARPHRD_6LOWPAN) &&
3467 	    (dev->type != ARPHRD_IP6GRE) &&
3468 	    (dev->type != ARPHRD_TUNNEL) &&
3469 	    (dev->type != ARPHRD_NONE) &&
3470 	    (dev->type != ARPHRD_RAWIP)) {
3471 		/* Alas, we support only Ethernet autoconfiguration. */
3472 		idev = __in6_dev_get(dev);
3473 		if (!IS_ERR_OR_NULL(idev) && dev->flags & IFF_UP &&
3474 		    dev->flags & IFF_MULTICAST)
3475 			ipv6_mc_up(idev);
3476 		return;
3477 	}
3478 
3479 	idev = addrconf_add_dev(dev);
3480 	if (IS_ERR(idev))
3481 		return;
3482 
3483 	/* this device type has no EUI support */
3484 	if (dev->type == ARPHRD_NONE &&
3485 	    idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)
3486 		WRITE_ONCE(idev->cnf.addr_gen_mode,
3487 			   IN6_ADDR_GEN_MODE_RANDOM);
3488 
3489 	addrconf_addr_gen(idev, false);
3490 }
3491 
3492 #if IS_ENABLED(CONFIG_IPV6_SIT)
addrconf_sit_config(struct net_device * dev)3493 static void addrconf_sit_config(struct net_device *dev)
3494 {
3495 	struct inet6_dev *idev;
3496 
3497 	ASSERT_RTNL();
3498 
3499 	/*
3500 	 * Configure the tunnel with one of our IPv4
3501 	 * addresses... we should configure all of
3502 	 * our v4 addrs in the tunnel
3503 	 */
3504 
3505 	idev = ipv6_find_idev(dev);
3506 	if (IS_ERR(idev)) {
3507 		pr_debug("%s: add_dev failed\n", __func__);
3508 		return;
3509 	}
3510 
3511 	if (dev->priv_flags & IFF_ISATAP) {
3512 		addrconf_addr_gen(idev, false);
3513 		return;
3514 	}
3515 
3516 	add_v4_addrs(idev);
3517 
3518 	if (dev->flags&IFF_POINTOPOINT)
3519 		addrconf_add_mroute(dev);
3520 }
3521 #endif
3522 
3523 #if IS_ENABLED(CONFIG_NET_IPGRE)
addrconf_gre_config(struct net_device * dev)3524 static void addrconf_gre_config(struct net_device *dev)
3525 {
3526 	struct inet6_dev *idev;
3527 
3528 	ASSERT_RTNL();
3529 
3530 	idev = addrconf_add_dev(dev);
3531 	if (IS_ERR(idev))
3532 		return;
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 (!(*(__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 #endif
3548 
addrconf_init_auto_addrs(struct net_device * dev)3549 static void addrconf_init_auto_addrs(struct net_device *dev)
3550 {
3551 	switch (dev->type) {
3552 #if IS_ENABLED(CONFIG_IPV6_SIT)
3553 	case ARPHRD_SIT:
3554 		addrconf_sit_config(dev);
3555 		break;
3556 #endif
3557 #if IS_ENABLED(CONFIG_NET_IPGRE)
3558 	case ARPHRD_IPGRE:
3559 		addrconf_gre_config(dev);
3560 		break;
3561 #endif
3562 	case ARPHRD_LOOPBACK:
3563 		init_loopback(dev);
3564 		break;
3565 
3566 	default:
3567 		addrconf_dev_config(dev);
3568 		break;
3569 	}
3570 }
3571 
fixup_permanent_addr(struct net * net,struct inet6_dev * idev,struct inet6_ifaddr * ifp)3572 static int fixup_permanent_addr(struct net *net,
3573 				struct inet6_dev *idev,
3574 				struct inet6_ifaddr *ifp)
3575 {
3576 	/* !fib6_node means the host route was removed from the
3577 	 * FIB, for example, if 'lo' device is taken down. In that
3578 	 * case regenerate the host route.
3579 	 */
3580 	if (!ifp->rt || !ifp->rt->fib6_node) {
3581 		struct fib6_info *f6i, *prev;
3582 
3583 		f6i = addrconf_f6i_alloc(net, idev, &ifp->addr, false,
3584 					 GFP_ATOMIC, NULL);
3585 		if (IS_ERR(f6i))
3586 			return PTR_ERR(f6i);
3587 
3588 		/* ifp->rt can be accessed outside of rtnl */
3589 		spin_lock(&ifp->lock);
3590 		prev = ifp->rt;
3591 		ifp->rt = f6i;
3592 		spin_unlock(&ifp->lock);
3593 
3594 		fib6_info_release(prev);
3595 	}
3596 
3597 	if (!(ifp->flags & IFA_F_NOPREFIXROUTE)) {
3598 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3599 				      ifp->rt_priority, idev->dev, 0, 0,
3600 				      GFP_ATOMIC);
3601 	}
3602 
3603 	if (ifp->state == INET6_IFADDR_STATE_PREDAD)
3604 		addrconf_dad_start(ifp);
3605 
3606 	return 0;
3607 }
3608 
addrconf_permanent_addr(struct net * net,struct net_device * dev)3609 static void addrconf_permanent_addr(struct net *net, struct net_device *dev)
3610 {
3611 	struct inet6_ifaddr *ifp, *tmp;
3612 	struct inet6_dev *idev;
3613 
3614 	idev = __in6_dev_get(dev);
3615 	if (!idev)
3616 		return;
3617 
3618 	write_lock_bh(&idev->lock);
3619 
3620 	list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
3621 		if ((ifp->flags & IFA_F_PERMANENT) &&
3622 		    fixup_permanent_addr(net, idev, ifp) < 0) {
3623 			write_unlock_bh(&idev->lock);
3624 			in6_ifa_hold(ifp);
3625 			ipv6_del_addr(ifp);
3626 			write_lock_bh(&idev->lock);
3627 
3628 			net_info_ratelimited("%s: Failed to add prefix route for address %pI6c; dropping\n",
3629 					     idev->dev->name, &ifp->addr);
3630 		}
3631 	}
3632 
3633 	write_unlock_bh(&idev->lock);
3634 }
3635 
addrconf_notify(struct notifier_block * this,unsigned long event,void * ptr)3636 static int addrconf_notify(struct notifier_block *this, unsigned long event,
3637 			   void *ptr)
3638 {
3639 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3640 	struct netdev_notifier_change_info *change_info;
3641 	struct netdev_notifier_changeupper_info *info;
3642 	struct inet6_dev *idev = __in6_dev_get(dev);
3643 	struct net *net = dev_net(dev);
3644 	int run_pending = 0;
3645 	int err;
3646 
3647 	switch (event) {
3648 	case NETDEV_REGISTER:
3649 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3650 			idev = ipv6_add_dev(dev);
3651 			if (IS_ERR(idev))
3652 				return notifier_from_errno(PTR_ERR(idev));
3653 		}
3654 		break;
3655 
3656 	case NETDEV_CHANGEMTU:
3657 		/* if MTU under IPV6_MIN_MTU stop IPv6 on this interface. */
3658 		if (dev->mtu < IPV6_MIN_MTU) {
3659 			addrconf_ifdown(dev, dev != net->loopback_dev);
3660 			break;
3661 		}
3662 
3663 		if (idev) {
3664 			rt6_mtu_change(dev, dev->mtu);
3665 			WRITE_ONCE(idev->cnf.mtu6, dev->mtu);
3666 			break;
3667 		}
3668 
3669 		/* allocate new idev */
3670 		idev = ipv6_add_dev(dev);
3671 		if (IS_ERR(idev))
3672 			break;
3673 
3674 		/* device is still not ready */
3675 		if (!(idev->if_flags & IF_READY))
3676 			break;
3677 
3678 		run_pending = 1;
3679 		fallthrough;
3680 	case NETDEV_UP:
3681 	case NETDEV_CHANGE:
3682 		if (idev && idev->cnf.disable_ipv6)
3683 			break;
3684 
3685 		if (dev->priv_flags & IFF_NO_ADDRCONF) {
3686 			if (event == NETDEV_UP && !IS_ERR_OR_NULL(idev) &&
3687 			    dev->flags & IFF_UP && dev->flags & IFF_MULTICAST)
3688 				ipv6_mc_up(idev);
3689 			break;
3690 		}
3691 
3692 		if (event == NETDEV_UP) {
3693 			/* restore routes for permanent addresses */
3694 			addrconf_permanent_addr(net, dev);
3695 
3696 			if (!addrconf_link_ready(dev)) {
3697 				/* device is not ready yet. */
3698 				pr_debug("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
3699 					 dev->name);
3700 				break;
3701 			}
3702 
3703 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
3704 				idev = ipv6_add_dev(dev);
3705 
3706 			if (!IS_ERR_OR_NULL(idev)) {
3707 				idev->if_flags |= IF_READY;
3708 				run_pending = 1;
3709 			}
3710 		} else if (event == NETDEV_CHANGE) {
3711 			if (!addrconf_link_ready(dev)) {
3712 				/* device is still not ready. */
3713 				rt6_sync_down_dev(dev, event);
3714 				break;
3715 			}
3716 
3717 			if (!IS_ERR_OR_NULL(idev)) {
3718 				if (idev->if_flags & IF_READY) {
3719 					/* device is already configured -
3720 					 * but resend MLD reports, we might
3721 					 * have roamed and need to update
3722 					 * multicast snooping switches
3723 					 */
3724 					ipv6_mc_up(idev);
3725 					change_info = ptr;
3726 					if (change_info->flags_changed & IFF_NOARP)
3727 						addrconf_dad_run(idev, true);
3728 					rt6_sync_up(dev, RTNH_F_LINKDOWN);
3729 					break;
3730 				}
3731 				idev->if_flags |= IF_READY;
3732 			}
3733 
3734 			pr_debug("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
3735 				 dev->name);
3736 
3737 			run_pending = 1;
3738 		}
3739 
3740 		addrconf_init_auto_addrs(dev);
3741 
3742 		if (!IS_ERR_OR_NULL(idev)) {
3743 			if (run_pending)
3744 				addrconf_dad_run(idev, false);
3745 
3746 			/* Device has an address by now */
3747 			rt6_sync_up(dev, RTNH_F_DEAD);
3748 
3749 			/*
3750 			 * If the MTU changed during the interface down,
3751 			 * when the interface up, the changed MTU must be
3752 			 * reflected in the idev as well as routers.
3753 			 */
3754 			if (idev->cnf.mtu6 != dev->mtu &&
3755 			    dev->mtu >= IPV6_MIN_MTU) {
3756 				rt6_mtu_change(dev, dev->mtu);
3757 				WRITE_ONCE(idev->cnf.mtu6, dev->mtu);
3758 			}
3759 			WRITE_ONCE(idev->tstamp, jiffies);
3760 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
3761 
3762 			/*
3763 			 * If the changed mtu during down is lower than
3764 			 * IPV6_MIN_MTU stop IPv6 on this interface.
3765 			 */
3766 			if (dev->mtu < IPV6_MIN_MTU)
3767 				addrconf_ifdown(dev, dev != net->loopback_dev);
3768 		}
3769 		break;
3770 
3771 	case NETDEV_DOWN:
3772 	case NETDEV_UNREGISTER:
3773 		/*
3774 		 *	Remove all addresses from this interface.
3775 		 */
3776 		addrconf_ifdown(dev, event != NETDEV_DOWN);
3777 		break;
3778 
3779 	case NETDEV_CHANGENAME:
3780 		if (idev) {
3781 			snmp6_unregister_dev(idev);
3782 			addrconf_sysctl_unregister(idev);
3783 			err = addrconf_sysctl_register(idev);
3784 			if (err)
3785 				return notifier_from_errno(err);
3786 			err = snmp6_register_dev(idev);
3787 			if (err) {
3788 				addrconf_sysctl_unregister(idev);
3789 				return notifier_from_errno(err);
3790 			}
3791 		}
3792 		break;
3793 
3794 	case NETDEV_PRE_TYPE_CHANGE:
3795 	case NETDEV_POST_TYPE_CHANGE:
3796 		if (idev)
3797 			addrconf_type_change(dev, event);
3798 		break;
3799 
3800 	case NETDEV_CHANGEUPPER:
3801 		info = ptr;
3802 
3803 		/* flush all routes if dev is linked to or unlinked from
3804 		 * an L3 master device (e.g., VRF)
3805 		 */
3806 		if (info->upper_dev && netif_is_l3_master(info->upper_dev))
3807 			addrconf_ifdown(dev, false);
3808 	}
3809 
3810 	return NOTIFY_OK;
3811 }
3812 
3813 /*
3814  *	addrconf module should be notified of a device going up
3815  */
3816 static struct notifier_block ipv6_dev_notf = {
3817 	.notifier_call = addrconf_notify,
3818 	.priority = ADDRCONF_NOTIFY_PRIORITY,
3819 };
3820 
addrconf_type_change(struct net_device * dev,unsigned long event)3821 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3822 {
3823 	struct inet6_dev *idev;
3824 	ASSERT_RTNL();
3825 
3826 	idev = __in6_dev_get(dev);
3827 
3828 	if (event == NETDEV_POST_TYPE_CHANGE)
3829 		ipv6_mc_remap(idev);
3830 	else if (event == NETDEV_PRE_TYPE_CHANGE)
3831 		ipv6_mc_unmap(idev);
3832 }
3833 
addr_is_local(const struct in6_addr * addr)3834 static bool addr_is_local(const struct in6_addr *addr)
3835 {
3836 	return ipv6_addr_type(addr) &
3837 		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
3838 }
3839 
addrconf_ifdown(struct net_device * dev,bool unregister)3840 static int addrconf_ifdown(struct net_device *dev, bool unregister)
3841 {
3842 	unsigned long event = unregister ? NETDEV_UNREGISTER : NETDEV_DOWN;
3843 	struct net *net = dev_net(dev);
3844 	struct inet6_dev *idev;
3845 	struct inet6_ifaddr *ifa;
3846 	LIST_HEAD(tmp_addr_list);
3847 	bool keep_addr = false;
3848 	bool was_ready;
3849 	int state, i;
3850 
3851 	ASSERT_RTNL();
3852 
3853 	rt6_disable_ip(dev, event);
3854 
3855 	idev = __in6_dev_get(dev);
3856 	if (!idev)
3857 		return -ENODEV;
3858 
3859 	/*
3860 	 * Step 1: remove reference to ipv6 device from parent device.
3861 	 *	   Do not dev_put!
3862 	 */
3863 	if (unregister) {
3864 		WRITE_ONCE(idev->dead, 1);
3865 
3866 		/* protected by rtnl_lock */
3867 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3868 
3869 		/* Step 1.5: remove snmp6 entry */
3870 		snmp6_unregister_dev(idev);
3871 
3872 	}
3873 
3874 	/* combine the user config with event to determine if permanent
3875 	 * addresses are to be removed from address hash table
3876 	 */
3877 	if (!unregister && !idev->cnf.disable_ipv6) {
3878 		/* aggregate the system setting and interface setting */
3879 		int _keep_addr = READ_ONCE(net->ipv6.devconf_all->keep_addr_on_down);
3880 
3881 		if (!_keep_addr)
3882 			_keep_addr = READ_ONCE(idev->cnf.keep_addr_on_down);
3883 
3884 		keep_addr = (_keep_addr > 0);
3885 	}
3886 
3887 	/* Step 2: clear hash table */
3888 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3889 		struct hlist_head *h = &net->ipv6.inet6_addr_lst[i];
3890 
3891 		spin_lock_bh(&net->ipv6.addrconf_hash_lock);
3892 restart:
3893 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3894 			if (ifa->idev == idev) {
3895 				addrconf_del_dad_work(ifa);
3896 				/* combined flag + permanent flag decide if
3897 				 * address is retained on a down event
3898 				 */
3899 				if (!keep_addr ||
3900 				    !(ifa->flags & IFA_F_PERMANENT) ||
3901 				    addr_is_local(&ifa->addr)) {
3902 					hlist_del_init_rcu(&ifa->addr_lst);
3903 					goto restart;
3904 				}
3905 			}
3906 		}
3907 		spin_unlock_bh(&net->ipv6.addrconf_hash_lock);
3908 	}
3909 
3910 	write_lock_bh(&idev->lock);
3911 
3912 	addrconf_del_rs_timer(idev);
3913 
3914 	/* Step 2: clear flags for stateless addrconf, repeated down
3915 	 *         detection
3916 	 */
3917 	was_ready = idev->if_flags & IF_READY;
3918 	if (!unregister)
3919 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3920 
3921 	/* Step 3: clear tempaddr list */
3922 	while (!list_empty(&idev->tempaddr_list)) {
3923 		ifa = list_first_entry(&idev->tempaddr_list,
3924 				       struct inet6_ifaddr, tmp_list);
3925 		list_del(&ifa->tmp_list);
3926 		write_unlock_bh(&idev->lock);
3927 		spin_lock_bh(&ifa->lock);
3928 
3929 		if (ifa->ifpub) {
3930 			in6_ifa_put(ifa->ifpub);
3931 			ifa->ifpub = NULL;
3932 		}
3933 		spin_unlock_bh(&ifa->lock);
3934 		in6_ifa_put(ifa);
3935 		write_lock_bh(&idev->lock);
3936 	}
3937 
3938 	list_for_each_entry(ifa, &idev->addr_list, if_list)
3939 		list_add_tail(&ifa->if_list_aux, &tmp_addr_list);
3940 	write_unlock_bh(&idev->lock);
3941 
3942 	while (!list_empty(&tmp_addr_list)) {
3943 		struct fib6_info *rt = NULL;
3944 		bool keep;
3945 
3946 		ifa = list_first_entry(&tmp_addr_list,
3947 				       struct inet6_ifaddr, if_list_aux);
3948 		list_del(&ifa->if_list_aux);
3949 
3950 		addrconf_del_dad_work(ifa);
3951 
3952 		keep = keep_addr && (ifa->flags & IFA_F_PERMANENT) &&
3953 			!addr_is_local(&ifa->addr);
3954 
3955 		spin_lock_bh(&ifa->lock);
3956 
3957 		if (keep) {
3958 			/* set state to skip the notifier below */
3959 			state = INET6_IFADDR_STATE_DEAD;
3960 			ifa->state = INET6_IFADDR_STATE_PREDAD;
3961 			if (!(ifa->flags & IFA_F_NODAD))
3962 				ifa->flags |= IFA_F_TENTATIVE;
3963 
3964 			rt = ifa->rt;
3965 			ifa->rt = NULL;
3966 		} else {
3967 			state = ifa->state;
3968 			ifa->state = INET6_IFADDR_STATE_DEAD;
3969 		}
3970 
3971 		spin_unlock_bh(&ifa->lock);
3972 
3973 		if (rt)
3974 			ip6_del_rt(net, rt, false);
3975 
3976 		if (state != INET6_IFADDR_STATE_DEAD) {
3977 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3978 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3979 		} else {
3980 			if (idev->cnf.forwarding)
3981 				addrconf_leave_anycast(ifa);
3982 			addrconf_leave_solict(ifa->idev, &ifa->addr);
3983 		}
3984 
3985 		if (!keep) {
3986 			write_lock_bh(&idev->lock);
3987 			list_del_rcu(&ifa->if_list);
3988 			write_unlock_bh(&idev->lock);
3989 			in6_ifa_put(ifa);
3990 		}
3991 	}
3992 
3993 	/* Step 5: Discard anycast and multicast list */
3994 	if (unregister) {
3995 		ipv6_ac_destroy_dev(idev);
3996 		ipv6_mc_destroy_dev(idev);
3997 	} else if (was_ready) {
3998 		ipv6_mc_down(idev);
3999 	}
4000 
4001 	WRITE_ONCE(idev->tstamp, jiffies);
4002 	idev->ra_mtu = 0;
4003 
4004 	/* Last: Shot the device (if unregistered) */
4005 	if (unregister) {
4006 		addrconf_sysctl_unregister(idev);
4007 		neigh_parms_release(&nd_tbl, idev->nd_parms);
4008 		neigh_ifdown(&nd_tbl, dev);
4009 		in6_dev_put(idev);
4010 	}
4011 	return 0;
4012 }
4013 
addrconf_rs_timer(struct timer_list * t)4014 static void addrconf_rs_timer(struct timer_list *t)
4015 {
4016 	struct inet6_dev *idev = timer_container_of(idev, t, rs_timer);
4017 	struct net_device *dev = idev->dev;
4018 	struct in6_addr lladdr;
4019 	int rtr_solicits;
4020 
4021 	write_lock(&idev->lock);
4022 	if (idev->dead || !(idev->if_flags & IF_READY))
4023 		goto out;
4024 
4025 	if (!ipv6_accept_ra(idev))
4026 		goto out;
4027 
4028 	/* Announcement received after solicitation was sent */
4029 	if (idev->if_flags & IF_RA_RCVD)
4030 		goto out;
4031 
4032 	rtr_solicits = READ_ONCE(idev->cnf.rtr_solicits);
4033 
4034 	if (idev->rs_probes++ < rtr_solicits || rtr_solicits < 0) {
4035 		write_unlock(&idev->lock);
4036 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4037 			ndisc_send_rs(dev, &lladdr,
4038 				      &in6addr_linklocal_allrouters);
4039 		else
4040 			goto put;
4041 
4042 		write_lock(&idev->lock);
4043 		idev->rs_interval = rfc3315_s14_backoff_update(
4044 				idev->rs_interval,
4045 				READ_ONCE(idev->cnf.rtr_solicit_max_interval));
4046 		/* The wait after the last probe can be shorter */
4047 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
4048 					     READ_ONCE(idev->cnf.rtr_solicits)) ?
4049 				      READ_ONCE(idev->cnf.rtr_solicit_delay) :
4050 				      idev->rs_interval);
4051 	} else {
4052 		/*
4053 		 * Note: we do not support deprecated "all on-link"
4054 		 * assumption any longer.
4055 		 */
4056 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
4057 	}
4058 
4059 out:
4060 	write_unlock(&idev->lock);
4061 put:
4062 	in6_dev_put(idev);
4063 }
4064 
4065 /*
4066  *	Duplicate Address Detection
4067  */
addrconf_dad_kick(struct inet6_ifaddr * ifp)4068 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
4069 {
4070 	struct inet6_dev *idev = ifp->idev;
4071 	unsigned long rand_num;
4072 	u64 nonce;
4073 
4074 	if (ifp->flags & IFA_F_OPTIMISTIC)
4075 		rand_num = 0;
4076 	else
4077 		rand_num = get_random_u32_below(
4078 				READ_ONCE(idev->cnf.rtr_solicit_delay) ? : 1);
4079 
4080 	nonce = 0;
4081 	if (READ_ONCE(idev->cnf.enhanced_dad) ||
4082 	    READ_ONCE(dev_net(idev->dev)->ipv6.devconf_all->enhanced_dad)) {
4083 		do
4084 			get_random_bytes(&nonce, 6);
4085 		while (nonce == 0);
4086 	}
4087 	ifp->dad_nonce = nonce;
4088 	ifp->dad_probes = READ_ONCE(idev->cnf.dad_transmits);
4089 	addrconf_mod_dad_work(ifp, rand_num);
4090 }
4091 
addrconf_dad_begin(struct inet6_ifaddr * ifp)4092 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
4093 {
4094 	struct inet6_dev *idev = ifp->idev;
4095 	struct net_device *dev = idev->dev;
4096 	bool bump_id, notify = false;
4097 	struct net *net;
4098 
4099 	addrconf_join_solict(dev, &ifp->addr);
4100 
4101 	read_lock_bh(&idev->lock);
4102 	spin_lock(&ifp->lock);
4103 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
4104 		goto out;
4105 
4106 	net = dev_net(dev);
4107 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
4108 	    (READ_ONCE(net->ipv6.devconf_all->accept_dad) < 1 &&
4109 	     READ_ONCE(idev->cnf.accept_dad) < 1) ||
4110 	    !(ifp->flags&IFA_F_TENTATIVE) ||
4111 	    ifp->flags & IFA_F_NODAD) {
4112 		bool send_na = false;
4113 
4114 		if (ifp->flags & IFA_F_TENTATIVE &&
4115 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4116 			send_na = true;
4117 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4118 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4119 		spin_unlock(&ifp->lock);
4120 		read_unlock_bh(&idev->lock);
4121 
4122 		addrconf_dad_completed(ifp, bump_id, send_na);
4123 		return;
4124 	}
4125 
4126 	if (!(idev->if_flags & IF_READY)) {
4127 		spin_unlock(&ifp->lock);
4128 		read_unlock_bh(&idev->lock);
4129 		/*
4130 		 * If the device is not ready:
4131 		 * - keep it tentative if it is a permanent address.
4132 		 * - otherwise, kill it.
4133 		 */
4134 		in6_ifa_hold(ifp);
4135 		addrconf_dad_stop(ifp, 0);
4136 		return;
4137 	}
4138 
4139 	/*
4140 	 * Optimistic nodes can start receiving
4141 	 * Frames right away
4142 	 */
4143 	if (ifp->flags & IFA_F_OPTIMISTIC) {
4144 		ip6_ins_rt(net, ifp->rt);
4145 		if (ipv6_use_optimistic_addr(net, idev)) {
4146 			/* Because optimistic nodes can use this address,
4147 			 * notify listeners. If DAD fails, RTM_DELADDR is sent.
4148 			 */
4149 			notify = true;
4150 		}
4151 	}
4152 
4153 	addrconf_dad_kick(ifp);
4154 out:
4155 	spin_unlock(&ifp->lock);
4156 	read_unlock_bh(&idev->lock);
4157 	if (notify)
4158 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
4159 }
4160 
addrconf_dad_start(struct inet6_ifaddr * ifp)4161 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
4162 {
4163 	bool begin_dad = false;
4164 
4165 	spin_lock_bh(&ifp->lock);
4166 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
4167 		ifp->state = INET6_IFADDR_STATE_PREDAD;
4168 		begin_dad = true;
4169 	}
4170 	spin_unlock_bh(&ifp->lock);
4171 
4172 	if (begin_dad)
4173 		addrconf_mod_dad_work(ifp, 0);
4174 }
4175 
addrconf_dad_work(struct work_struct * w)4176 static void addrconf_dad_work(struct work_struct *w)
4177 {
4178 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
4179 						struct inet6_ifaddr,
4180 						dad_work);
4181 	struct inet6_dev *idev = ifp->idev;
4182 	bool bump_id, disable_ipv6 = false;
4183 	struct in6_addr mcaddr;
4184 	struct net *net;
4185 
4186 	enum {
4187 		DAD_PROCESS,
4188 		DAD_BEGIN,
4189 		DAD_ABORT,
4190 	} action = DAD_PROCESS;
4191 
4192 	net = dev_net(idev->dev);
4193 
4194 	rtnl_net_lock(net);
4195 
4196 	spin_lock_bh(&ifp->lock);
4197 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
4198 		action = DAD_BEGIN;
4199 		ifp->state = INET6_IFADDR_STATE_DAD;
4200 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
4201 		action = DAD_ABORT;
4202 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
4203 
4204 		if ((READ_ONCE(net->ipv6.devconf_all->accept_dad) > 1 ||
4205 		     READ_ONCE(idev->cnf.accept_dad) > 1) &&
4206 		    !idev->cnf.disable_ipv6 &&
4207 		    !(ifp->flags & IFA_F_STABLE_PRIVACY)) {
4208 			struct in6_addr addr;
4209 
4210 			addr.s6_addr32[0] = htonl(0xfe800000);
4211 			addr.s6_addr32[1] = 0;
4212 
4213 			if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
4214 			    ipv6_addr_equal(&ifp->addr, &addr)) {
4215 				/* DAD failed for link-local based on MAC */
4216 				WRITE_ONCE(idev->cnf.disable_ipv6, 1);
4217 
4218 				pr_info("%s: IPv6 being disabled!\n",
4219 					ifp->idev->dev->name);
4220 				disable_ipv6 = true;
4221 			}
4222 		}
4223 	}
4224 	spin_unlock_bh(&ifp->lock);
4225 
4226 	if (action == DAD_BEGIN) {
4227 		addrconf_dad_begin(ifp);
4228 		goto out;
4229 	} else if (action == DAD_ABORT) {
4230 		in6_ifa_hold(ifp);
4231 		addrconf_dad_stop(ifp, 1);
4232 		if (disable_ipv6)
4233 			addrconf_ifdown(idev->dev, false);
4234 		goto out;
4235 	}
4236 
4237 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
4238 		goto out;
4239 
4240 	write_lock_bh(&idev->lock);
4241 	if (idev->dead || !(idev->if_flags & IF_READY)) {
4242 		write_unlock_bh(&idev->lock);
4243 		goto out;
4244 	}
4245 
4246 	spin_lock(&ifp->lock);
4247 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
4248 		spin_unlock(&ifp->lock);
4249 		write_unlock_bh(&idev->lock);
4250 		goto out;
4251 	}
4252 
4253 	if (ifp->dad_probes == 0) {
4254 		bool send_na = false;
4255 
4256 		/*
4257 		 * DAD was successful
4258 		 */
4259 
4260 		if (ifp->flags & IFA_F_TENTATIVE &&
4261 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4262 			send_na = true;
4263 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4264 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4265 		spin_unlock(&ifp->lock);
4266 		write_unlock_bh(&idev->lock);
4267 
4268 		addrconf_dad_completed(ifp, bump_id, send_na);
4269 
4270 		goto out;
4271 	}
4272 
4273 	ifp->dad_probes--;
4274 	addrconf_mod_dad_work(ifp,
4275 			      max(NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME),
4276 				  HZ/100));
4277 	spin_unlock(&ifp->lock);
4278 	write_unlock_bh(&idev->lock);
4279 
4280 	/* send a neighbour solicitation for our addr */
4281 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
4282 	ndisc_send_ns(ifp->idev->dev, &ifp->addr, &mcaddr, &in6addr_any,
4283 		      ifp->dad_nonce);
4284 out:
4285 	in6_ifa_put(ifp);
4286 	rtnl_net_unlock(net);
4287 }
4288 
4289 /* ifp->idev must be at least read locked */
ipv6_lonely_lladdr(struct inet6_ifaddr * ifp)4290 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
4291 {
4292 	struct inet6_ifaddr *ifpiter;
4293 	struct inet6_dev *idev = ifp->idev;
4294 
4295 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
4296 		if (ifpiter->scope > IFA_LINK)
4297 			break;
4298 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
4299 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
4300 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
4301 		    IFA_F_PERMANENT)
4302 			return false;
4303 	}
4304 	return true;
4305 }
4306 
addrconf_dad_completed(struct inet6_ifaddr * ifp,bool bump_id,bool send_na)4307 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
4308 				   bool send_na)
4309 {
4310 	struct net_device *dev = ifp->idev->dev;
4311 	struct in6_addr lladdr;
4312 	bool send_rs, send_mld;
4313 
4314 	addrconf_del_dad_work(ifp);
4315 
4316 	/*
4317 	 *	Configure the address for reception. Now it is valid.
4318 	 */
4319 
4320 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
4321 
4322 	/* If added prefix is link local and we are prepared to process
4323 	   router advertisements, start sending router solicitations.
4324 	 */
4325 
4326 	read_lock_bh(&ifp->idev->lock);
4327 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
4328 	send_rs = send_mld &&
4329 		  ipv6_accept_ra(ifp->idev) &&
4330 		  READ_ONCE(ifp->idev->cnf.rtr_solicits) != 0 &&
4331 		  (dev->flags & IFF_LOOPBACK) == 0 &&
4332 		  (dev->type != ARPHRD_TUNNEL) &&
4333 		  !netif_is_team_port(dev);
4334 	read_unlock_bh(&ifp->idev->lock);
4335 
4336 	/* While dad is in progress mld report's source address is in6_addrany.
4337 	 * Resend with proper ll now.
4338 	 */
4339 	if (send_mld)
4340 		ipv6_mc_dad_complete(ifp->idev);
4341 
4342 	/* send unsolicited NA if enabled */
4343 	if (send_na &&
4344 	    (READ_ONCE(ifp->idev->cnf.ndisc_notify) ||
4345 	     READ_ONCE(dev_net(dev)->ipv6.devconf_all->ndisc_notify))) {
4346 		ndisc_send_na(dev, &in6addr_linklocal_allnodes, &ifp->addr,
4347 			      /*router=*/ !!ifp->idev->cnf.forwarding,
4348 			      /*solicited=*/ false, /*override=*/ true,
4349 			      /*inc_opt=*/ true);
4350 	}
4351 
4352 	if (send_rs) {
4353 		/*
4354 		 *	If a host as already performed a random delay
4355 		 *	[...] as part of DAD [...] there is no need
4356 		 *	to delay again before sending the first RS
4357 		 */
4358 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4359 			return;
4360 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
4361 
4362 		write_lock_bh(&ifp->idev->lock);
4363 		spin_lock(&ifp->lock);
4364 		ifp->idev->rs_interval = rfc3315_s14_backoff_init(
4365 			READ_ONCE(ifp->idev->cnf.rtr_solicit_interval));
4366 		ifp->idev->rs_probes = 1;
4367 		ifp->idev->if_flags |= IF_RS_SENT;
4368 		addrconf_mod_rs_timer(ifp->idev, ifp->idev->rs_interval);
4369 		spin_unlock(&ifp->lock);
4370 		write_unlock_bh(&ifp->idev->lock);
4371 	}
4372 
4373 	if (bump_id)
4374 		rt_genid_bump_ipv6(dev_net(dev));
4375 
4376 	/* Make sure that a new temporary address will be created
4377 	 * before this temporary address becomes deprecated.
4378 	 */
4379 	if (ifp->flags & IFA_F_TEMPORARY)
4380 		addrconf_verify_rtnl(dev_net(dev));
4381 }
4382 
addrconf_dad_run(struct inet6_dev * idev,bool restart)4383 static void addrconf_dad_run(struct inet6_dev *idev, bool restart)
4384 {
4385 	struct inet6_ifaddr *ifp;
4386 
4387 	read_lock_bh(&idev->lock);
4388 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4389 		spin_lock(&ifp->lock);
4390 		if ((ifp->flags & IFA_F_TENTATIVE &&
4391 		     ifp->state == INET6_IFADDR_STATE_DAD) || restart) {
4392 			if (restart)
4393 				ifp->state = INET6_IFADDR_STATE_PREDAD;
4394 			addrconf_dad_kick(ifp);
4395 		}
4396 		spin_unlock(&ifp->lock);
4397 	}
4398 	read_unlock_bh(&idev->lock);
4399 }
4400 
4401 #ifdef CONFIG_PROC_FS
4402 struct if6_iter_state {
4403 	struct seq_net_private p;
4404 	int bucket;
4405 	int offset;
4406 };
4407 
if6_get_first(struct seq_file * seq,loff_t pos)4408 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
4409 {
4410 	struct if6_iter_state *state = seq->private;
4411 	struct net *net = seq_file_net(seq);
4412 	struct inet6_ifaddr *ifa = NULL;
4413 	int p = 0;
4414 
4415 	/* initial bucket if pos is 0 */
4416 	if (pos == 0) {
4417 		state->bucket = 0;
4418 		state->offset = 0;
4419 	}
4420 
4421 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
4422 		hlist_for_each_entry_rcu(ifa, &net->ipv6.inet6_addr_lst[state->bucket],
4423 					 addr_lst) {
4424 			/* sync with offset */
4425 			if (p < state->offset) {
4426 				p++;
4427 				continue;
4428 			}
4429 			return ifa;
4430 		}
4431 
4432 		/* prepare for next bucket */
4433 		state->offset = 0;
4434 		p = 0;
4435 	}
4436 	return NULL;
4437 }
4438 
if6_get_next(struct seq_file * seq,struct inet6_ifaddr * ifa)4439 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
4440 					 struct inet6_ifaddr *ifa)
4441 {
4442 	struct if6_iter_state *state = seq->private;
4443 	struct net *net = seq_file_net(seq);
4444 
4445 	hlist_for_each_entry_continue_rcu(ifa, addr_lst) {
4446 		state->offset++;
4447 		return ifa;
4448 	}
4449 
4450 	state->offset = 0;
4451 	while (++state->bucket < IN6_ADDR_HSIZE) {
4452 		hlist_for_each_entry_rcu(ifa,
4453 				     &net->ipv6.inet6_addr_lst[state->bucket], addr_lst) {
4454 			return ifa;
4455 		}
4456 	}
4457 
4458 	return NULL;
4459 }
4460 
if6_seq_start(struct seq_file * seq,loff_t * pos)4461 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
4462 	__acquires(rcu)
4463 {
4464 	rcu_read_lock();
4465 	return if6_get_first(seq, *pos);
4466 }
4467 
if6_seq_next(struct seq_file * seq,void * v,loff_t * pos)4468 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4469 {
4470 	struct inet6_ifaddr *ifa;
4471 
4472 	ifa = if6_get_next(seq, v);
4473 	++*pos;
4474 	return ifa;
4475 }
4476 
if6_seq_stop(struct seq_file * seq,void * v)4477 static void if6_seq_stop(struct seq_file *seq, void *v)
4478 	__releases(rcu)
4479 {
4480 	rcu_read_unlock();
4481 }
4482 
if6_seq_show(struct seq_file * seq,void * v)4483 static int if6_seq_show(struct seq_file *seq, void *v)
4484 {
4485 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
4486 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
4487 		   &ifp->addr,
4488 		   ifp->idev->dev->ifindex,
4489 		   ifp->prefix_len,
4490 		   ifp->scope,
4491 		   (u8) ifp->flags,
4492 		   ifp->idev->dev->name);
4493 	return 0;
4494 }
4495 
4496 static const struct seq_operations if6_seq_ops = {
4497 	.start	= if6_seq_start,
4498 	.next	= if6_seq_next,
4499 	.show	= if6_seq_show,
4500 	.stop	= if6_seq_stop,
4501 };
4502 
if6_proc_net_init(struct net * net)4503 static int __net_init if6_proc_net_init(struct net *net)
4504 {
4505 	if (!proc_create_net("if_inet6", 0444, net->proc_net, &if6_seq_ops,
4506 			sizeof(struct if6_iter_state)))
4507 		return -ENOMEM;
4508 	return 0;
4509 }
4510 
if6_proc_net_exit(struct net * net)4511 static void __net_exit if6_proc_net_exit(struct net *net)
4512 {
4513 	remove_proc_entry("if_inet6", net->proc_net);
4514 }
4515 
4516 static struct pernet_operations if6_proc_net_ops = {
4517 	.init = if6_proc_net_init,
4518 	.exit = if6_proc_net_exit,
4519 };
4520 
if6_proc_init(void)4521 int __init if6_proc_init(void)
4522 {
4523 	return register_pernet_subsys(&if6_proc_net_ops);
4524 }
4525 
if6_proc_exit(void)4526 void if6_proc_exit(void)
4527 {
4528 	unregister_pernet_subsys(&if6_proc_net_ops);
4529 }
4530 #endif	/* CONFIG_PROC_FS */
4531 
4532 #if IS_ENABLED(CONFIG_IPV6_MIP6)
4533 /* Check if address is a home address configured on any interface. */
ipv6_chk_home_addr(struct net * net,const struct in6_addr * addr)4534 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
4535 {
4536 	unsigned int hash = inet6_addr_hash(net, addr);
4537 	struct inet6_ifaddr *ifp = NULL;
4538 	int ret = 0;
4539 
4540 	rcu_read_lock();
4541 	hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
4542 		if (ipv6_addr_equal(&ifp->addr, addr) &&
4543 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
4544 			ret = 1;
4545 			break;
4546 		}
4547 	}
4548 	rcu_read_unlock();
4549 	return ret;
4550 }
4551 #endif
4552 
4553 /* RFC6554 has some algorithm to avoid loops in segment routing by
4554  * checking if the segments contains any of a local interface address.
4555  *
4556  * Quote:
4557  *
4558  * To detect loops in the SRH, a router MUST determine if the SRH
4559  * includes multiple addresses assigned to any interface on that router.
4560  * If such addresses appear more than once and are separated by at least
4561  * one address not assigned to that router.
4562  */
ipv6_chk_rpl_srh_loop(struct net * net,const struct in6_addr * segs,unsigned char nsegs)4563 int ipv6_chk_rpl_srh_loop(struct net *net, const struct in6_addr *segs,
4564 			  unsigned char nsegs)
4565 {
4566 	const struct in6_addr *addr;
4567 	int i, ret = 0, found = 0;
4568 	struct inet6_ifaddr *ifp;
4569 	bool separated = false;
4570 	unsigned int hash;
4571 	bool hash_found;
4572 
4573 	rcu_read_lock();
4574 	for (i = 0; i < nsegs; i++) {
4575 		addr = &segs[i];
4576 		hash = inet6_addr_hash(net, addr);
4577 
4578 		hash_found = false;
4579 		hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
4580 
4581 			if (ipv6_addr_equal(&ifp->addr, addr)) {
4582 				hash_found = true;
4583 				break;
4584 			}
4585 		}
4586 
4587 		if (hash_found) {
4588 			if (found > 1 && separated) {
4589 				ret = 1;
4590 				break;
4591 			}
4592 
4593 			separated = false;
4594 			found++;
4595 		} else {
4596 			separated = true;
4597 		}
4598 	}
4599 	rcu_read_unlock();
4600 
4601 	return ret;
4602 }
4603 
4604 /*
4605  *	Periodic address status verification
4606  */
4607 
addrconf_verify_rtnl(struct net * net)4608 static void addrconf_verify_rtnl(struct net *net)
4609 {
4610 	unsigned long now, next, next_sec, next_sched;
4611 	struct inet6_ifaddr *ifp;
4612 	int i;
4613 
4614 	ASSERT_RTNL();
4615 
4616 	rcu_read_lock_bh();
4617 	now = jiffies;
4618 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
4619 
4620 	cancel_delayed_work(&net->ipv6.addr_chk_work);
4621 
4622 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
4623 restart:
4624 		hlist_for_each_entry_rcu_bh(ifp, &net->ipv6.inet6_addr_lst[i], addr_lst) {
4625 			unsigned long age;
4626 
4627 			/* When setting preferred_lft to a value not zero or
4628 			 * infinity, while valid_lft is infinity
4629 			 * IFA_F_PERMANENT has a non-infinity life time.
4630 			 */
4631 			if ((ifp->flags & IFA_F_PERMANENT) &&
4632 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
4633 				continue;
4634 
4635 			spin_lock(&ifp->lock);
4636 			/* We try to batch several events at once. */
4637 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
4638 
4639 			if ((ifp->flags&IFA_F_TEMPORARY) &&
4640 			    !(ifp->flags&IFA_F_TENTATIVE) &&
4641 			    ifp->prefered_lft != INFINITY_LIFE_TIME &&
4642 			    !ifp->regen_count && ifp->ifpub) {
4643 				/* This is a non-regenerated temporary addr. */
4644 
4645 				unsigned long regen_advance = ipv6_get_regen_advance(ifp->idev);
4646 
4647 				if (age + regen_advance >= ifp->prefered_lft) {
4648 					struct inet6_ifaddr *ifpub = ifp->ifpub;
4649 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4650 						next = ifp->tstamp + ifp->prefered_lft * HZ;
4651 
4652 					ifp->regen_count++;
4653 					in6_ifa_hold(ifp);
4654 					in6_ifa_hold(ifpub);
4655 					spin_unlock(&ifp->lock);
4656 
4657 					spin_lock(&ifpub->lock);
4658 					ifpub->regen_count = 0;
4659 					spin_unlock(&ifpub->lock);
4660 					rcu_read_unlock_bh();
4661 					ipv6_create_tempaddr(ifpub, true);
4662 					in6_ifa_put(ifpub);
4663 					in6_ifa_put(ifp);
4664 					rcu_read_lock_bh();
4665 					goto restart;
4666 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
4667 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
4668 			}
4669 
4670 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
4671 			    age >= ifp->valid_lft) {
4672 				spin_unlock(&ifp->lock);
4673 				in6_ifa_hold(ifp);
4674 				rcu_read_unlock_bh();
4675 				ipv6_del_addr(ifp);
4676 				rcu_read_lock_bh();
4677 				goto restart;
4678 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
4679 				spin_unlock(&ifp->lock);
4680 				continue;
4681 			} else if (age >= ifp->prefered_lft) {
4682 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
4683 				int deprecate = 0;
4684 
4685 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
4686 					deprecate = 1;
4687 					ifp->flags |= IFA_F_DEPRECATED;
4688 				}
4689 
4690 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
4691 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
4692 					next = ifp->tstamp + ifp->valid_lft * HZ;
4693 
4694 				spin_unlock(&ifp->lock);
4695 
4696 				if (deprecate) {
4697 					in6_ifa_hold(ifp);
4698 
4699 					ipv6_ifa_notify(0, ifp);
4700 					in6_ifa_put(ifp);
4701 					goto restart;
4702 				}
4703 			} else {
4704 				/* ifp->prefered_lft <= ifp->valid_lft */
4705 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4706 					next = ifp->tstamp + ifp->prefered_lft * HZ;
4707 				spin_unlock(&ifp->lock);
4708 			}
4709 		}
4710 	}
4711 
4712 	next_sec = round_jiffies_up(next);
4713 	next_sched = next;
4714 
4715 	/* If rounded timeout is accurate enough, accept it. */
4716 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
4717 		next_sched = next_sec;
4718 
4719 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
4720 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
4721 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
4722 
4723 	pr_debug("now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
4724 		 now, next, next_sec, next_sched);
4725 	mod_delayed_work(addrconf_wq, &net->ipv6.addr_chk_work, next_sched - now);
4726 	rcu_read_unlock_bh();
4727 }
4728 
addrconf_verify_work(struct work_struct * w)4729 static void addrconf_verify_work(struct work_struct *w)
4730 {
4731 	struct net *net = container_of(to_delayed_work(w), struct net,
4732 				       ipv6.addr_chk_work);
4733 
4734 	rtnl_net_lock(net);
4735 	addrconf_verify_rtnl(net);
4736 	rtnl_net_unlock(net);
4737 }
4738 
addrconf_verify(struct net * net)4739 static void addrconf_verify(struct net *net)
4740 {
4741 	mod_delayed_work(addrconf_wq, &net->ipv6.addr_chk_work, 0);
4742 }
4743 
extract_addr(struct nlattr * addr,struct nlattr * local,struct in6_addr ** peer_pfx)4744 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
4745 				     struct in6_addr **peer_pfx)
4746 {
4747 	struct in6_addr *pfx = NULL;
4748 
4749 	*peer_pfx = NULL;
4750 
4751 	if (addr)
4752 		pfx = nla_data(addr);
4753 
4754 	if (local) {
4755 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
4756 			*peer_pfx = pfx;
4757 		pfx = nla_data(local);
4758 	}
4759 
4760 	return pfx;
4761 }
4762 
4763 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
4764 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
4765 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
4766 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
4767 	[IFA_FLAGS]		= { .len = sizeof(u32) },
4768 	[IFA_RT_PRIORITY]	= { .len = sizeof(u32) },
4769 	[IFA_TARGET_NETNSID]	= { .type = NLA_S32 },
4770 	[IFA_PROTO]		= { .type = NLA_U8 },
4771 };
4772 
4773 static int
inet6_rtm_deladdr(struct sk_buff * skb,struct nlmsghdr * nlh,struct netlink_ext_ack * extack)4774 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
4775 		  struct netlink_ext_ack *extack)
4776 {
4777 	struct net *net = sock_net(skb->sk);
4778 	struct ifaddrmsg *ifm;
4779 	struct nlattr *tb[IFA_MAX+1];
4780 	struct in6_addr *pfx, *peer_pfx;
4781 	u32 ifa_flags;
4782 	int err;
4783 
4784 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4785 				     ifa_ipv6_policy, extack);
4786 	if (err < 0)
4787 		return err;
4788 
4789 	ifm = nlmsg_data(nlh);
4790 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4791 	if (!pfx)
4792 		return -EINVAL;
4793 
4794 	ifa_flags = nla_get_u32_default(tb[IFA_FLAGS], ifm->ifa_flags);
4795 
4796 	/* We ignore other flags so far. */
4797 	ifa_flags &= IFA_F_MANAGETEMPADDR;
4798 
4799 	rtnl_net_lock(net);
4800 	err = inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
4801 			     ifm->ifa_prefixlen, extack);
4802 	rtnl_net_unlock(net);
4803 
4804 	return err;
4805 }
4806 
modify_prefix_route(struct net * net,struct inet6_ifaddr * ifp,unsigned long expires,u32 flags,bool modify_peer)4807 static int modify_prefix_route(struct net *net, struct inet6_ifaddr *ifp,
4808 			       unsigned long expires, u32 flags,
4809 			       bool modify_peer)
4810 {
4811 	struct fib6_table *table;
4812 	struct fib6_info *f6i;
4813 	u32 prio;
4814 
4815 	f6i = addrconf_get_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
4816 					ifp->prefix_len,
4817 					ifp->idev->dev, 0, RTF_DEFAULT, true);
4818 	if (!f6i)
4819 		return -ENOENT;
4820 
4821 	prio = ifp->rt_priority ? : IP6_RT_PRIO_ADDRCONF;
4822 	if (f6i->fib6_metric != prio) {
4823 		/* delete old one */
4824 		ip6_del_rt(dev_net(ifp->idev->dev), f6i, false);
4825 
4826 		/* add new one */
4827 		addrconf_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
4828 				      ifp->prefix_len,
4829 				      ifp->rt_priority, ifp->idev->dev,
4830 				      expires, flags, GFP_KERNEL);
4831 		return 0;
4832 	}
4833 	if (f6i != net->ipv6.fib6_null_entry) {
4834 		table = f6i->fib6_table;
4835 		spin_lock_bh(&table->tb6_lock);
4836 
4837 		if (!(flags & RTF_EXPIRES)) {
4838 			fib6_clean_expires(f6i);
4839 			fib6_remove_gc_list(f6i);
4840 		} else {
4841 			fib6_set_expires(f6i, expires);
4842 			fib6_add_gc_list(f6i);
4843 		}
4844 
4845 		spin_unlock_bh(&table->tb6_lock);
4846 	}
4847 	fib6_info_release(f6i);
4848 
4849 	return 0;
4850 }
4851 
inet6_addr_modify(struct net * net,struct inet6_ifaddr * ifp,struct ifa6_config * cfg,clock_t expires,u32 flags)4852 static int inet6_addr_modify(struct net *net, struct inet6_ifaddr *ifp,
4853 			     struct ifa6_config *cfg, clock_t expires,
4854 			     u32 flags)
4855 {
4856 	bool was_managetempaddr;
4857 	bool new_peer = false;
4858 	bool had_prefixroute;
4859 
4860 	ASSERT_RTNL_NET(net);
4861 
4862 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR &&
4863 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
4864 		return -EINVAL;
4865 
4866 	if (!(ifp->flags & IFA_F_TENTATIVE) || ifp->flags & IFA_F_DADFAILED)
4867 		cfg->ifa_flags &= ~IFA_F_OPTIMISTIC;
4868 
4869 	if (cfg->peer_pfx &&
4870 	    memcmp(&ifp->peer_addr, cfg->peer_pfx, sizeof(struct in6_addr))) {
4871 		if (!ipv6_addr_any(&ifp->peer_addr))
4872 			cleanup_prefix_route(ifp, expires, true, true);
4873 		new_peer = true;
4874 	}
4875 
4876 	spin_lock_bh(&ifp->lock);
4877 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
4878 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
4879 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
4880 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
4881 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4882 			IFA_F_NOPREFIXROUTE);
4883 	ifp->flags |= cfg->ifa_flags;
4884 	WRITE_ONCE(ifp->tstamp, jiffies);
4885 	WRITE_ONCE(ifp->valid_lft, cfg->valid_lft);
4886 	WRITE_ONCE(ifp->prefered_lft, cfg->preferred_lft);
4887 	WRITE_ONCE(ifp->ifa_proto, cfg->ifa_proto);
4888 
4889 	if (cfg->rt_priority && cfg->rt_priority != ifp->rt_priority)
4890 		WRITE_ONCE(ifp->rt_priority, cfg->rt_priority);
4891 
4892 	if (new_peer)
4893 		ifp->peer_addr = *cfg->peer_pfx;
4894 
4895 	spin_unlock_bh(&ifp->lock);
4896 	if (!(ifp->flags&IFA_F_TENTATIVE))
4897 		ipv6_ifa_notify(0, ifp);
4898 
4899 	if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
4900 		int rc = -ENOENT;
4901 
4902 		if (had_prefixroute)
4903 			rc = modify_prefix_route(net, ifp, expires, flags, false);
4904 
4905 		/* prefix route could have been deleted; if so restore it */
4906 		if (rc == -ENOENT) {
4907 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
4908 					      ifp->rt_priority, ifp->idev->dev,
4909 					      expires, flags, GFP_KERNEL);
4910 		}
4911 
4912 		if (had_prefixroute && !ipv6_addr_any(&ifp->peer_addr))
4913 			rc = modify_prefix_route(net, ifp, expires, flags, true);
4914 
4915 		if (rc == -ENOENT && !ipv6_addr_any(&ifp->peer_addr)) {
4916 			addrconf_prefix_route(&ifp->peer_addr, ifp->prefix_len,
4917 					      ifp->rt_priority, ifp->idev->dev,
4918 					      expires, flags, GFP_KERNEL);
4919 		}
4920 	} else if (had_prefixroute) {
4921 		enum cleanup_prefix_rt_t action;
4922 		unsigned long rt_expires;
4923 
4924 		write_lock_bh(&ifp->idev->lock);
4925 		action = check_cleanup_prefix_route(ifp, &rt_expires);
4926 		write_unlock_bh(&ifp->idev->lock);
4927 
4928 		if (action != CLEANUP_PREFIX_RT_NOP) {
4929 			cleanup_prefix_route(ifp, rt_expires,
4930 				action == CLEANUP_PREFIX_RT_DEL, false);
4931 		}
4932 	}
4933 
4934 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
4935 		if (was_managetempaddr && !(ifp->flags & IFA_F_MANAGETEMPADDR))
4936 			delete_tempaddrs(ifp->idev, ifp);
4937 		else
4938 			manage_tempaddrs(ifp->idev, ifp, cfg->valid_lft,
4939 					 cfg->preferred_lft, !was_managetempaddr,
4940 					 jiffies);
4941 	}
4942 
4943 	addrconf_verify_rtnl(net);
4944 
4945 	return 0;
4946 }
4947 
4948 static int
inet6_rtm_newaddr(struct sk_buff * skb,struct nlmsghdr * nlh,struct netlink_ext_ack * extack)4949 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
4950 		  struct netlink_ext_ack *extack)
4951 {
4952 	struct net *net = sock_net(skb->sk);
4953 	struct nlattr *tb[IFA_MAX+1];
4954 	struct in6_addr *peer_pfx;
4955 	struct inet6_ifaddr *ifa;
4956 	struct net_device *dev;
4957 	struct inet6_dev *idev;
4958 	struct ifa6_config cfg;
4959 	struct ifaddrmsg *ifm;
4960 	unsigned long timeout;
4961 	clock_t expires;
4962 	u32 flags;
4963 	int err;
4964 
4965 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4966 				     ifa_ipv6_policy, extack);
4967 	if (err < 0)
4968 		return err;
4969 
4970 	memset(&cfg, 0, sizeof(cfg));
4971 
4972 	ifm = nlmsg_data(nlh);
4973 	cfg.pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4974 	if (!cfg.pfx)
4975 		return -EINVAL;
4976 
4977 	cfg.peer_pfx = peer_pfx;
4978 	cfg.plen = ifm->ifa_prefixlen;
4979 	if (tb[IFA_RT_PRIORITY])
4980 		cfg.rt_priority = nla_get_u32(tb[IFA_RT_PRIORITY]);
4981 
4982 	if (tb[IFA_PROTO])
4983 		cfg.ifa_proto = nla_get_u8(tb[IFA_PROTO]);
4984 
4985 	cfg.ifa_flags = nla_get_u32_default(tb[IFA_FLAGS], ifm->ifa_flags);
4986 
4987 	/* We ignore other flags so far. */
4988 	cfg.ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS |
4989 			 IFA_F_MANAGETEMPADDR | IFA_F_NOPREFIXROUTE |
4990 			 IFA_F_MCAUTOJOIN | IFA_F_OPTIMISTIC;
4991 
4992 	cfg.ifa_flags |= IFA_F_PERMANENT;
4993 	cfg.valid_lft = INFINITY_LIFE_TIME;
4994 	cfg.preferred_lft = INFINITY_LIFE_TIME;
4995 	expires = 0;
4996 	flags = 0;
4997 
4998 	if (tb[IFA_CACHEINFO]) {
4999 		struct ifa_cacheinfo *ci;
5000 
5001 		ci = nla_data(tb[IFA_CACHEINFO]);
5002 		cfg.valid_lft = ci->ifa_valid;
5003 		cfg.preferred_lft = ci->ifa_prefered;
5004 
5005 		if (!cfg.valid_lft || cfg.preferred_lft > cfg.valid_lft) {
5006 			NL_SET_ERR_MSG_MOD(extack, "address lifetime invalid");
5007 			return -EINVAL;
5008 		}
5009 
5010 		timeout = addrconf_timeout_fixup(cfg.valid_lft, HZ);
5011 		if (addrconf_finite_timeout(timeout)) {
5012 			cfg.ifa_flags &= ~IFA_F_PERMANENT;
5013 			cfg.valid_lft = timeout;
5014 			expires = jiffies_to_clock_t(timeout * HZ);
5015 			flags = RTF_EXPIRES;
5016 		}
5017 
5018 		timeout = addrconf_timeout_fixup(cfg.preferred_lft, HZ);
5019 		if (addrconf_finite_timeout(timeout)) {
5020 			if (timeout == 0)
5021 				cfg.ifa_flags |= IFA_F_DEPRECATED;
5022 
5023 			cfg.preferred_lft = timeout;
5024 		}
5025 	}
5026 
5027 	rtnl_net_lock(net);
5028 
5029 	dev =  __dev_get_by_index(net, ifm->ifa_index);
5030 	if (!dev) {
5031 		NL_SET_ERR_MSG_MOD(extack, "Unable to find the interface");
5032 		err = -ENODEV;
5033 		goto unlock_rtnl;
5034 	}
5035 
5036 	netdev_lock_ops(dev);
5037 	idev = ipv6_find_idev(dev);
5038 	if (IS_ERR(idev)) {
5039 		err = PTR_ERR(idev);
5040 		goto unlock;
5041 	}
5042 
5043 	if (!ipv6_allow_optimistic_dad(net, idev))
5044 		cfg.ifa_flags &= ~IFA_F_OPTIMISTIC;
5045 
5046 	if (cfg.ifa_flags & IFA_F_NODAD &&
5047 	    cfg.ifa_flags & IFA_F_OPTIMISTIC) {
5048 		NL_SET_ERR_MSG(extack, "IFA_F_NODAD and IFA_F_OPTIMISTIC are mutually exclusive");
5049 		err = -EINVAL;
5050 		goto unlock;
5051 	}
5052 
5053 	ifa = ipv6_get_ifaddr(net, cfg.pfx, dev, 1);
5054 	if (!ifa) {
5055 		/*
5056 		 * It would be best to check for !NLM_F_CREATE here but
5057 		 * userspace already relies on not having to provide this.
5058 		 */
5059 		err = inet6_addr_add(net, dev, &cfg, expires, flags, extack);
5060 		goto unlock;
5061 	}
5062 
5063 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
5064 	    !(nlh->nlmsg_flags & NLM_F_REPLACE)) {
5065 		NL_SET_ERR_MSG_MOD(extack, "address already assigned");
5066 		err = -EEXIST;
5067 	} else {
5068 		err = inet6_addr_modify(net, ifa, &cfg, expires, flags);
5069 	}
5070 
5071 	in6_ifa_put(ifa);
5072 unlock:
5073 	netdev_unlock_ops(dev);
5074 unlock_rtnl:
5075 	rtnl_net_unlock(net);
5076 
5077 	return err;
5078 }
5079 
put_ifaddrmsg(struct nlmsghdr * nlh,u8 prefixlen,u32 flags,u8 scope,int ifindex)5080 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
5081 			  u8 scope, int ifindex)
5082 {
5083 	struct ifaddrmsg *ifm;
5084 
5085 	ifm = nlmsg_data(nlh);
5086 	ifm->ifa_family = AF_INET6;
5087 	ifm->ifa_prefixlen = prefixlen;
5088 	ifm->ifa_flags = flags;
5089 	ifm->ifa_scope = scope;
5090 	ifm->ifa_index = ifindex;
5091 }
5092 
put_cacheinfo(struct sk_buff * skb,unsigned long cstamp,unsigned long tstamp,u32 preferred,u32 valid)5093 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
5094 			 unsigned long tstamp, u32 preferred, u32 valid)
5095 {
5096 	struct ifa_cacheinfo ci;
5097 
5098 	ci.cstamp = cstamp_delta(cstamp);
5099 	ci.tstamp = cstamp_delta(tstamp);
5100 	ci.ifa_prefered = preferred;
5101 	ci.ifa_valid = valid;
5102 
5103 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
5104 }
5105 
rt_scope(int ifa_scope)5106 static inline int rt_scope(int ifa_scope)
5107 {
5108 	if (ifa_scope & IFA_HOST)
5109 		return RT_SCOPE_HOST;
5110 	else if (ifa_scope & IFA_LINK)
5111 		return RT_SCOPE_LINK;
5112 	else if (ifa_scope & IFA_SITE)
5113 		return RT_SCOPE_SITE;
5114 	else
5115 		return RT_SCOPE_UNIVERSE;
5116 }
5117 
inet6_ifaddr_msgsize(void)5118 static inline int inet6_ifaddr_msgsize(void)
5119 {
5120 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
5121 	       + nla_total_size(16) /* IFA_LOCAL */
5122 	       + nla_total_size(16) /* IFA_ADDRESS */
5123 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
5124 	       + nla_total_size(4)  /* IFA_FLAGS */
5125 	       + nla_total_size(1)  /* IFA_PROTO */
5126 	       + nla_total_size(4)  /* IFA_RT_PRIORITY */;
5127 }
5128 
inet6_fill_ifaddr(struct sk_buff * skb,const struct inet6_ifaddr * ifa,struct inet6_fill_args * args)5129 static int inet6_fill_ifaddr(struct sk_buff *skb,
5130 			     const struct inet6_ifaddr *ifa,
5131 			     struct inet6_fill_args *args)
5132 {
5133 	struct nlmsghdr *nlh;
5134 	u32 preferred, valid;
5135 	u32 flags, priority;
5136 	u8 proto;
5137 
5138 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5139 			sizeof(struct ifaddrmsg), args->flags);
5140 	if (!nlh)
5141 		return -EMSGSIZE;
5142 
5143 	flags = READ_ONCE(ifa->flags);
5144 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
5145 		      ifa->idev->dev->ifindex);
5146 
5147 	if (args->netnsid >= 0 &&
5148 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
5149 		goto error;
5150 
5151 	preferred = READ_ONCE(ifa->prefered_lft);
5152 	valid = READ_ONCE(ifa->valid_lft);
5153 
5154 	if (!((flags & IFA_F_PERMANENT) &&
5155 	      (preferred == INFINITY_LIFE_TIME))) {
5156 		if (preferred != INFINITY_LIFE_TIME) {
5157 			long tval = (jiffies - READ_ONCE(ifa->tstamp)) / HZ;
5158 
5159 			if (preferred > tval)
5160 				preferred -= tval;
5161 			else
5162 				preferred = 0;
5163 			if (valid != INFINITY_LIFE_TIME) {
5164 				if (valid > tval)
5165 					valid -= tval;
5166 				else
5167 					valid = 0;
5168 			}
5169 		}
5170 	} else {
5171 		preferred = INFINITY_LIFE_TIME;
5172 		valid = INFINITY_LIFE_TIME;
5173 	}
5174 
5175 	if (!ipv6_addr_any(&ifa->peer_addr)) {
5176 		if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||
5177 		    nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0)
5178 			goto error;
5179 	} else {
5180 		if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0)
5181 			goto error;
5182 	}
5183 
5184 	priority = READ_ONCE(ifa->rt_priority);
5185 	if (priority && nla_put_u32(skb, IFA_RT_PRIORITY, priority))
5186 		goto error;
5187 
5188 	if (put_cacheinfo(skb, ifa->cstamp, READ_ONCE(ifa->tstamp),
5189 			  preferred, valid) < 0)
5190 		goto error;
5191 
5192 	if (nla_put_u32(skb, IFA_FLAGS, flags) < 0)
5193 		goto error;
5194 
5195 	proto = READ_ONCE(ifa->ifa_proto);
5196 	if (proto && nla_put_u8(skb, IFA_PROTO, proto))
5197 		goto error;
5198 
5199 	nlmsg_end(skb, nlh);
5200 	return 0;
5201 
5202 error:
5203 	nlmsg_cancel(skb, nlh);
5204 	return -EMSGSIZE;
5205 }
5206 
inet6_fill_ifmcaddr(struct sk_buff * skb,const struct ifmcaddr6 * ifmca,struct inet6_fill_args * args)5207 int inet6_fill_ifmcaddr(struct sk_buff *skb,
5208 			const struct ifmcaddr6 *ifmca,
5209 			struct inet6_fill_args *args)
5210 {
5211 	int ifindex = ifmca->idev->dev->ifindex;
5212 	u8 scope = RT_SCOPE_UNIVERSE;
5213 	struct nlmsghdr *nlh;
5214 
5215 	if (!args->force_rt_scope_universe &&
5216 	    ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
5217 		scope = RT_SCOPE_SITE;
5218 
5219 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5220 			sizeof(struct ifaddrmsg), args->flags);
5221 	if (!nlh)
5222 		return -EMSGSIZE;
5223 
5224 	if (args->netnsid >= 0 &&
5225 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid)) {
5226 		nlmsg_cancel(skb, nlh);
5227 		return -EMSGSIZE;
5228 	}
5229 
5230 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
5231 	if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
5232 	    put_cacheinfo(skb, ifmca->mca_cstamp, READ_ONCE(ifmca->mca_tstamp),
5233 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
5234 		nlmsg_cancel(skb, nlh);
5235 		return -EMSGSIZE;
5236 	}
5237 
5238 	nlmsg_end(skb, nlh);
5239 	return 0;
5240 }
5241 
inet6_fill_ifacaddr(struct sk_buff * skb,const struct ifacaddr6 * ifaca,struct inet6_fill_args * args)5242 int inet6_fill_ifacaddr(struct sk_buff *skb,
5243 			const struct ifacaddr6 *ifaca,
5244 			struct inet6_fill_args *args)
5245 {
5246 	struct net_device *dev = fib6_info_nh_dev(ifaca->aca_rt);
5247 	int ifindex = dev ? dev->ifindex : 1;
5248 	u8 scope = RT_SCOPE_UNIVERSE;
5249 	struct nlmsghdr *nlh;
5250 
5251 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
5252 		scope = RT_SCOPE_SITE;
5253 
5254 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5255 			sizeof(struct ifaddrmsg), args->flags);
5256 	if (!nlh)
5257 		return -EMSGSIZE;
5258 
5259 	if (args->netnsid >= 0 &&
5260 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid)) {
5261 		nlmsg_cancel(skb, nlh);
5262 		return -EMSGSIZE;
5263 	}
5264 
5265 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
5266 	if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
5267 	    put_cacheinfo(skb, ifaca->aca_cstamp, READ_ONCE(ifaca->aca_tstamp),
5268 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
5269 		nlmsg_cancel(skb, nlh);
5270 		return -EMSGSIZE;
5271 	}
5272 
5273 	nlmsg_end(skb, nlh);
5274 	return 0;
5275 }
5276 
5277 /* 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)5278 static int in6_dump_addrs(const struct inet6_dev *idev, struct sk_buff *skb,
5279 			  struct netlink_callback *cb, int *s_ip_idx,
5280 			  struct inet6_fill_args *fillargs)
5281 {
5282 	const struct ifmcaddr6 *ifmca;
5283 	const struct ifacaddr6 *ifaca;
5284 	int ip_idx = 0;
5285 	int err = 0;
5286 
5287 	switch (fillargs->type) {
5288 	case UNICAST_ADDR: {
5289 		const struct inet6_ifaddr *ifa;
5290 		fillargs->event = RTM_NEWADDR;
5291 
5292 		/* unicast address incl. temp addr */
5293 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
5294 			if (ip_idx < *s_ip_idx)
5295 				goto next;
5296 			err = inet6_fill_ifaddr(skb, ifa, fillargs);
5297 			if (err < 0)
5298 				break;
5299 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
5300 next:
5301 			ip_idx++;
5302 		}
5303 		break;
5304 	}
5305 	case MULTICAST_ADDR:
5306 		fillargs->event = RTM_GETMULTICAST;
5307 
5308 		/* multicast address */
5309 		for (ifmca = rcu_dereference(idev->mc_list);
5310 		     ifmca;
5311 		     ifmca = rcu_dereference(ifmca->next), ip_idx++) {
5312 			if (ip_idx < *s_ip_idx)
5313 				continue;
5314 			err = inet6_fill_ifmcaddr(skb, ifmca, fillargs);
5315 			if (err < 0)
5316 				break;
5317 		}
5318 		break;
5319 	case ANYCAST_ADDR:
5320 		fillargs->event = RTM_GETANYCAST;
5321 		/* anycast address */
5322 		for (ifaca = rcu_dereference(idev->ac_list); ifaca;
5323 		     ifaca = rcu_dereference(ifaca->aca_next), ip_idx++) {
5324 			if (ip_idx < *s_ip_idx)
5325 				continue;
5326 			err = inet6_fill_ifacaddr(skb, ifaca, fillargs);
5327 			if (err < 0)
5328 				break;
5329 		}
5330 		break;
5331 	default:
5332 		break;
5333 	}
5334 	*s_ip_idx = err ? ip_idx : 0;
5335 	return err;
5336 }
5337 
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)5338 static int inet6_valid_dump_ifaddr_req(const struct nlmsghdr *nlh,
5339 				       struct inet6_fill_args *fillargs,
5340 				       struct net **tgt_net, struct sock *sk,
5341 				       struct netlink_callback *cb)
5342 {
5343 	struct netlink_ext_ack *extack = cb->extack;
5344 	struct nlattr *tb[IFA_MAX+1];
5345 	struct ifaddrmsg *ifm;
5346 	int err, i;
5347 
5348 	ifm = nlmsg_payload(nlh, sizeof(*ifm));
5349 	if (!ifm) {
5350 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for address dump request");
5351 		return -EINVAL;
5352 	}
5353 
5354 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5355 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for address dump request");
5356 		return -EINVAL;
5357 	}
5358 
5359 	fillargs->ifindex = ifm->ifa_index;
5360 	if (fillargs->ifindex) {
5361 		cb->answer_flags |= NLM_F_DUMP_FILTERED;
5362 		fillargs->flags |= NLM_F_DUMP_FILTERED;
5363 	}
5364 
5365 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5366 					    ifa_ipv6_policy, extack);
5367 	if (err < 0)
5368 		return err;
5369 
5370 	for (i = 0; i <= IFA_MAX; ++i) {
5371 		if (!tb[i])
5372 			continue;
5373 
5374 		if (i == IFA_TARGET_NETNSID) {
5375 			struct net *net;
5376 
5377 			fillargs->netnsid = nla_get_s32(tb[i]);
5378 			net = rtnl_get_net_ns_capable(sk, fillargs->netnsid);
5379 			if (IS_ERR(net)) {
5380 				fillargs->netnsid = -1;
5381 				NL_SET_ERR_MSG_MOD(extack, "Invalid target network namespace id");
5382 				return PTR_ERR(net);
5383 			}
5384 			*tgt_net = net;
5385 		} else {
5386 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in dump request");
5387 			return -EINVAL;
5388 		}
5389 	}
5390 
5391 	return 0;
5392 }
5393 
inet6_dump_addr(struct sk_buff * skb,struct netlink_callback * cb,enum addr_type_t type)5394 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
5395 			   enum addr_type_t type)
5396 {
5397 	struct net *tgt_net = sock_net(skb->sk);
5398 	const struct nlmsghdr *nlh = cb->nlh;
5399 	struct inet6_fill_args fillargs = {
5400 		.portid = NETLINK_CB(cb->skb).portid,
5401 		.seq = cb->nlh->nlmsg_seq,
5402 		.flags = NLM_F_MULTI,
5403 		.netnsid = -1,
5404 		.type = type,
5405 		.force_rt_scope_universe = false,
5406 	};
5407 	struct {
5408 		unsigned long ifindex;
5409 		int ip_idx;
5410 	} *ctx = (void *)cb->ctx;
5411 	struct net_device *dev;
5412 	struct inet6_dev *idev;
5413 	int err = 0;
5414 
5415 	rcu_read_lock();
5416 	if (cb->strict_check) {
5417 		err = inet6_valid_dump_ifaddr_req(nlh, &fillargs, &tgt_net,
5418 						  skb->sk, cb);
5419 		if (err < 0)
5420 			goto done;
5421 
5422 		err = 0;
5423 		if (fillargs.ifindex) {
5424 			dev = dev_get_by_index_rcu(tgt_net, fillargs.ifindex);
5425 			if (!dev) {
5426 				err = -ENODEV;
5427 				goto done;
5428 			}
5429 			idev = __in6_dev_get(dev);
5430 			if (idev)
5431 				err = in6_dump_addrs(idev, skb, cb,
5432 						     &ctx->ip_idx,
5433 						     &fillargs);
5434 			goto done;
5435 		}
5436 	}
5437 
5438 	cb->seq = inet6_base_seq(tgt_net);
5439 	for_each_netdev_dump(tgt_net, dev, ctx->ifindex) {
5440 		idev = __in6_dev_get(dev);
5441 		if (!idev)
5442 			continue;
5443 		err = in6_dump_addrs(idev, skb, cb, &ctx->ip_idx,
5444 				     &fillargs);
5445 		if (err < 0)
5446 			goto done;
5447 	}
5448 done:
5449 	rcu_read_unlock();
5450 	if (fillargs.netnsid >= 0)
5451 		put_net(tgt_net);
5452 
5453 	return err;
5454 }
5455 
inet6_dump_ifaddr(struct sk_buff * skb,struct netlink_callback * cb)5456 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
5457 {
5458 	enum addr_type_t type = UNICAST_ADDR;
5459 
5460 	return inet6_dump_addr(skb, cb, type);
5461 }
5462 
inet6_dump_ifmcaddr(struct sk_buff * skb,struct netlink_callback * cb)5463 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
5464 {
5465 	enum addr_type_t type = MULTICAST_ADDR;
5466 
5467 	return inet6_dump_addr(skb, cb, type);
5468 }
5469 
5470 
inet6_dump_ifacaddr(struct sk_buff * skb,struct netlink_callback * cb)5471 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
5472 {
5473 	enum addr_type_t type = ANYCAST_ADDR;
5474 
5475 	return inet6_dump_addr(skb, cb, type);
5476 }
5477 
inet6_rtm_valid_getaddr_req(struct sk_buff * skb,const struct nlmsghdr * nlh,struct nlattr ** tb,struct netlink_ext_ack * extack)5478 static int inet6_rtm_valid_getaddr_req(struct sk_buff *skb,
5479 				       const struct nlmsghdr *nlh,
5480 				       struct nlattr **tb,
5481 				       struct netlink_ext_ack *extack)
5482 {
5483 	struct ifaddrmsg *ifm;
5484 	int i, err;
5485 
5486 	ifm = nlmsg_payload(nlh, sizeof(*ifm));
5487 	if (!ifm) {
5488 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for get address request");
5489 		return -EINVAL;
5490 	}
5491 
5492 	if (!netlink_strict_get_check(skb))
5493 		return nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
5494 					      ifa_ipv6_policy, extack);
5495 
5496 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5497 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for get address request");
5498 		return -EINVAL;
5499 	}
5500 
5501 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5502 					    ifa_ipv6_policy, extack);
5503 	if (err)
5504 		return err;
5505 
5506 	for (i = 0; i <= IFA_MAX; i++) {
5507 		if (!tb[i])
5508 			continue;
5509 
5510 		switch (i) {
5511 		case IFA_TARGET_NETNSID:
5512 		case IFA_ADDRESS:
5513 		case IFA_LOCAL:
5514 			break;
5515 		default:
5516 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in get address request");
5517 			return -EINVAL;
5518 		}
5519 	}
5520 
5521 	return 0;
5522 }
5523 
inet6_rtm_getaddr(struct sk_buff * in_skb,struct nlmsghdr * nlh,struct netlink_ext_ack * extack)5524 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
5525 			     struct netlink_ext_ack *extack)
5526 {
5527 	struct net *tgt_net = sock_net(in_skb->sk);
5528 	struct inet6_fill_args fillargs = {
5529 		.portid = NETLINK_CB(in_skb).portid,
5530 		.seq = nlh->nlmsg_seq,
5531 		.event = RTM_NEWADDR,
5532 		.flags = 0,
5533 		.netnsid = -1,
5534 		.force_rt_scope_universe = false,
5535 	};
5536 	struct ifaddrmsg *ifm;
5537 	struct nlattr *tb[IFA_MAX+1];
5538 	struct in6_addr *addr = NULL, *peer;
5539 	struct net_device *dev = NULL;
5540 	struct inet6_ifaddr *ifa;
5541 	struct sk_buff *skb;
5542 	int err;
5543 
5544 	err = inet6_rtm_valid_getaddr_req(in_skb, nlh, tb, extack);
5545 	if (err < 0)
5546 		return err;
5547 
5548 	if (tb[IFA_TARGET_NETNSID]) {
5549 		fillargs.netnsid = nla_get_s32(tb[IFA_TARGET_NETNSID]);
5550 
5551 		tgt_net = rtnl_get_net_ns_capable(NETLINK_CB(in_skb).sk,
5552 						  fillargs.netnsid);
5553 		if (IS_ERR(tgt_net))
5554 			return PTR_ERR(tgt_net);
5555 	}
5556 
5557 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
5558 	if (!addr) {
5559 		err = -EINVAL;
5560 		goto errout;
5561 	}
5562 	ifm = nlmsg_data(nlh);
5563 	if (ifm->ifa_index)
5564 		dev = dev_get_by_index(tgt_net, ifm->ifa_index);
5565 
5566 	ifa = ipv6_get_ifaddr(tgt_net, addr, dev, 1);
5567 	if (!ifa) {
5568 		err = -EADDRNOTAVAIL;
5569 		goto errout;
5570 	}
5571 
5572 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
5573 	if (!skb) {
5574 		err = -ENOBUFS;
5575 		goto errout_ifa;
5576 	}
5577 
5578 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5579 	if (err < 0) {
5580 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5581 		WARN_ON(err == -EMSGSIZE);
5582 		kfree_skb(skb);
5583 		goto errout_ifa;
5584 	}
5585 	err = rtnl_unicast(skb, tgt_net, NETLINK_CB(in_skb).portid);
5586 errout_ifa:
5587 	in6_ifa_put(ifa);
5588 errout:
5589 	dev_put(dev);
5590 	if (fillargs.netnsid >= 0)
5591 		put_net(tgt_net);
5592 
5593 	return err;
5594 }
5595 
inet6_ifa_notify(int event,struct inet6_ifaddr * ifa)5596 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
5597 {
5598 	struct sk_buff *skb;
5599 	struct net *net = dev_net(ifa->idev->dev);
5600 	struct inet6_fill_args fillargs = {
5601 		.portid = 0,
5602 		.seq = 0,
5603 		.event = event,
5604 		.flags = 0,
5605 		.netnsid = -1,
5606 		.force_rt_scope_universe = false,
5607 	};
5608 	int err = -ENOBUFS;
5609 
5610 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
5611 	if (!skb)
5612 		goto errout;
5613 
5614 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5615 	if (err < 0) {
5616 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5617 		WARN_ON(err == -EMSGSIZE);
5618 		kfree_skb(skb);
5619 		goto errout;
5620 	}
5621 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
5622 	return;
5623 errout:
5624 	rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
5625 }
5626 
ipv6_store_devconf(const struct ipv6_devconf * cnf,__s32 * array,int bytes)5627 static void ipv6_store_devconf(const struct ipv6_devconf *cnf,
5628 			       __s32 *array, int bytes)
5629 {
5630 	BUG_ON(bytes < (DEVCONF_MAX * 4));
5631 
5632 	memset(array, 0, bytes);
5633 	array[DEVCONF_FORWARDING] = READ_ONCE(cnf->forwarding);
5634 	array[DEVCONF_HOPLIMIT] = READ_ONCE(cnf->hop_limit);
5635 	array[DEVCONF_MTU6] = READ_ONCE(cnf->mtu6);
5636 	array[DEVCONF_ACCEPT_RA] = READ_ONCE(cnf->accept_ra);
5637 	array[DEVCONF_ACCEPT_REDIRECTS] = READ_ONCE(cnf->accept_redirects);
5638 	array[DEVCONF_AUTOCONF] = READ_ONCE(cnf->autoconf);
5639 	array[DEVCONF_DAD_TRANSMITS] = READ_ONCE(cnf->dad_transmits);
5640 	array[DEVCONF_RTR_SOLICITS] = READ_ONCE(cnf->rtr_solicits);
5641 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
5642 		jiffies_to_msecs(READ_ONCE(cnf->rtr_solicit_interval));
5643 	array[DEVCONF_RTR_SOLICIT_MAX_INTERVAL] =
5644 		jiffies_to_msecs(READ_ONCE(cnf->rtr_solicit_max_interval));
5645 	array[DEVCONF_RTR_SOLICIT_DELAY] =
5646 		jiffies_to_msecs(READ_ONCE(cnf->rtr_solicit_delay));
5647 	array[DEVCONF_FORCE_MLD_VERSION] = READ_ONCE(cnf->force_mld_version);
5648 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
5649 		jiffies_to_msecs(READ_ONCE(cnf->mldv1_unsolicited_report_interval));
5650 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
5651 		jiffies_to_msecs(READ_ONCE(cnf->mldv2_unsolicited_report_interval));
5652 	array[DEVCONF_USE_TEMPADDR] = READ_ONCE(cnf->use_tempaddr);
5653 	array[DEVCONF_TEMP_VALID_LFT] = READ_ONCE(cnf->temp_valid_lft);
5654 	array[DEVCONF_TEMP_PREFERED_LFT] = READ_ONCE(cnf->temp_prefered_lft);
5655 	array[DEVCONF_REGEN_MAX_RETRY] = READ_ONCE(cnf->regen_max_retry);
5656 	array[DEVCONF_MAX_DESYNC_FACTOR] = READ_ONCE(cnf->max_desync_factor);
5657 	array[DEVCONF_MAX_ADDRESSES] = READ_ONCE(cnf->max_addresses);
5658 	array[DEVCONF_ACCEPT_RA_DEFRTR] = READ_ONCE(cnf->accept_ra_defrtr);
5659 	array[DEVCONF_RA_DEFRTR_METRIC] = READ_ONCE(cnf->ra_defrtr_metric);
5660 	array[DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT] =
5661 		READ_ONCE(cnf->accept_ra_min_hop_limit);
5662 	array[DEVCONF_ACCEPT_RA_PINFO] = READ_ONCE(cnf->accept_ra_pinfo);
5663 #ifdef CONFIG_IPV6_ROUTER_PREF
5664 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = READ_ONCE(cnf->accept_ra_rtr_pref);
5665 	array[DEVCONF_RTR_PROBE_INTERVAL] =
5666 		jiffies_to_msecs(READ_ONCE(cnf->rtr_probe_interval));
5667 #ifdef CONFIG_IPV6_ROUTE_INFO
5668 	array[DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN] =
5669 		READ_ONCE(cnf->accept_ra_rt_info_min_plen);
5670 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] =
5671 		READ_ONCE(cnf->accept_ra_rt_info_max_plen);
5672 #endif
5673 #endif
5674 	array[DEVCONF_PROXY_NDP] = READ_ONCE(cnf->proxy_ndp);
5675 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] =
5676 		READ_ONCE(cnf->accept_source_route);
5677 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5678 	array[DEVCONF_OPTIMISTIC_DAD] = READ_ONCE(cnf->optimistic_dad);
5679 	array[DEVCONF_USE_OPTIMISTIC] = READ_ONCE(cnf->use_optimistic);
5680 #endif
5681 #ifdef CONFIG_IPV6_MROUTE
5682 	array[DEVCONF_MC_FORWARDING] = atomic_read(&cnf->mc_forwarding);
5683 #endif
5684 	array[DEVCONF_DISABLE_IPV6] = READ_ONCE(cnf->disable_ipv6);
5685 	array[DEVCONF_ACCEPT_DAD] = READ_ONCE(cnf->accept_dad);
5686 	array[DEVCONF_FORCE_TLLAO] = READ_ONCE(cnf->force_tllao);
5687 	array[DEVCONF_NDISC_NOTIFY] = READ_ONCE(cnf->ndisc_notify);
5688 	array[DEVCONF_SUPPRESS_FRAG_NDISC] =
5689 		READ_ONCE(cnf->suppress_frag_ndisc);
5690 	array[DEVCONF_ACCEPT_RA_FROM_LOCAL] =
5691 		READ_ONCE(cnf->accept_ra_from_local);
5692 	array[DEVCONF_ACCEPT_RA_MTU] = READ_ONCE(cnf->accept_ra_mtu);
5693 	array[DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN] =
5694 		READ_ONCE(cnf->ignore_routes_with_linkdown);
5695 	/* we omit DEVCONF_STABLE_SECRET for now */
5696 	array[DEVCONF_USE_OIF_ADDRS_ONLY] = READ_ONCE(cnf->use_oif_addrs_only);
5697 	array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] =
5698 		READ_ONCE(cnf->drop_unicast_in_l2_multicast);
5699 	array[DEVCONF_DROP_UNSOLICITED_NA] = READ_ONCE(cnf->drop_unsolicited_na);
5700 	array[DEVCONF_KEEP_ADDR_ON_DOWN] = READ_ONCE(cnf->keep_addr_on_down);
5701 	array[DEVCONF_SEG6_ENABLED] = READ_ONCE(cnf->seg6_enabled);
5702 #ifdef CONFIG_IPV6_SEG6_HMAC
5703 	array[DEVCONF_SEG6_REQUIRE_HMAC] = READ_ONCE(cnf->seg6_require_hmac);
5704 #endif
5705 	array[DEVCONF_ENHANCED_DAD] = READ_ONCE(cnf->enhanced_dad);
5706 	array[DEVCONF_ADDR_GEN_MODE] = READ_ONCE(cnf->addr_gen_mode);
5707 	array[DEVCONF_DISABLE_POLICY] = READ_ONCE(cnf->disable_policy);
5708 	array[DEVCONF_NDISC_TCLASS] = READ_ONCE(cnf->ndisc_tclass);
5709 	array[DEVCONF_RPL_SEG_ENABLED] = READ_ONCE(cnf->rpl_seg_enabled);
5710 	array[DEVCONF_IOAM6_ENABLED] = READ_ONCE(cnf->ioam6_enabled);
5711 	array[DEVCONF_IOAM6_ID] = READ_ONCE(cnf->ioam6_id);
5712 	array[DEVCONF_IOAM6_ID_WIDE] = READ_ONCE(cnf->ioam6_id_wide);
5713 	array[DEVCONF_NDISC_EVICT_NOCARRIER] =
5714 		READ_ONCE(cnf->ndisc_evict_nocarrier);
5715 	array[DEVCONF_ACCEPT_UNTRACKED_NA] =
5716 		READ_ONCE(cnf->accept_untracked_na);
5717 	array[DEVCONF_ACCEPT_RA_MIN_LFT] = READ_ONCE(cnf->accept_ra_min_lft);
5718 	array[DEVCONF_FORCE_FORWARDING] = READ_ONCE(cnf->force_forwarding);
5719 }
5720 
inet6_ifla6_size(void)5721 static inline size_t inet6_ifla6_size(void)
5722 {
5723 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
5724 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
5725 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
5726 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
5727 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
5728 	     + nla_total_size(sizeof(struct in6_addr)) /* IFLA_INET6_TOKEN */
5729 	     + nla_total_size(1) /* IFLA_INET6_ADDR_GEN_MODE */
5730 	     + nla_total_size(4) /* IFLA_INET6_RA_MTU */
5731 	     + 0;
5732 }
5733 
inet6_if_nlmsg_size(void)5734 static inline size_t inet6_if_nlmsg_size(void)
5735 {
5736 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
5737 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
5738 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
5739 	       + nla_total_size(4) /* IFLA_MTU */
5740 	       + nla_total_size(4) /* IFLA_LINK */
5741 	       + nla_total_size(1) /* IFLA_OPERSTATE */
5742 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
5743 }
5744 
__snmp6_fill_statsdev(u64 * stats,atomic_long_t * mib,int bytes)5745 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
5746 					int bytes)
5747 {
5748 	int i;
5749 	int pad = bytes - sizeof(u64) * ICMP6_MIB_MAX;
5750 	BUG_ON(pad < 0);
5751 
5752 	/* Use put_unaligned() because stats may not be aligned for u64. */
5753 	put_unaligned(ICMP6_MIB_MAX, &stats[0]);
5754 	for (i = 1; i < ICMP6_MIB_MAX; i++)
5755 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
5756 
5757 	memset(&stats[ICMP6_MIB_MAX], 0, pad);
5758 }
5759 
__snmp6_fill_stats64(u64 * stats,void __percpu * mib,int bytes,size_t syncpoff)5760 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
5761 					int bytes, size_t syncpoff)
5762 {
5763 	int i, c;
5764 	u64 buff[IPSTATS_MIB_MAX];
5765 	int pad = bytes - sizeof(u64) * IPSTATS_MIB_MAX;
5766 
5767 	BUG_ON(pad < 0);
5768 
5769 	memset(buff, 0, sizeof(buff));
5770 	buff[0] = IPSTATS_MIB_MAX;
5771 
5772 	for_each_possible_cpu(c) {
5773 		for (i = 1; i < IPSTATS_MIB_MAX; i++)
5774 			buff[i] += snmp_get_cpu_field64(mib, c, i, syncpoff);
5775 	}
5776 
5777 	memcpy(stats, buff, IPSTATS_MIB_MAX * sizeof(u64));
5778 	memset(&stats[IPSTATS_MIB_MAX], 0, pad);
5779 }
5780 
snmp6_fill_stats(u64 * stats,struct inet6_dev * idev,int attrtype,int bytes)5781 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
5782 			     int bytes)
5783 {
5784 	switch (attrtype) {
5785 	case IFLA_INET6_STATS:
5786 		__snmp6_fill_stats64(stats, idev->stats.ipv6, bytes,
5787 				     offsetof(struct ipstats_mib, syncp));
5788 		break;
5789 	case IFLA_INET6_ICMP6STATS:
5790 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, bytes);
5791 		break;
5792 	}
5793 }
5794 
inet6_fill_ifla6_stats_attrs(struct sk_buff * skb,struct inet6_dev * idev)5795 static int inet6_fill_ifla6_stats_attrs(struct sk_buff *skb,
5796 					struct inet6_dev *idev)
5797 {
5798 	struct nlattr *nla;
5799 
5800 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
5801 	if (!nla)
5802 		goto nla_put_failure;
5803 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
5804 
5805 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
5806 	if (!nla)
5807 		goto nla_put_failure;
5808 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
5809 
5810 	return 0;
5811 
5812 nla_put_failure:
5813 	return -EMSGSIZE;
5814 }
5815 
inet6_fill_ifla6_attrs(struct sk_buff * skb,struct inet6_dev * idev,u32 ext_filter_mask)5816 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev,
5817 				  u32 ext_filter_mask)
5818 {
5819 	struct ifla_cacheinfo ci;
5820 	struct nlattr *nla;
5821 	u32 ra_mtu;
5822 
5823 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, READ_ONCE(idev->if_flags)))
5824 		goto nla_put_failure;
5825 	ci.max_reasm_len = IPV6_MAXPLEN;
5826 	ci.tstamp = cstamp_delta(READ_ONCE(idev->tstamp));
5827 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
5828 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
5829 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
5830 		goto nla_put_failure;
5831 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
5832 	if (!nla)
5833 		goto nla_put_failure;
5834 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
5835 
5836 	/* XXX - MC not implemented */
5837 
5838 	if (!(ext_filter_mask & RTEXT_FILTER_SKIP_STATS)) {
5839 		if (inet6_fill_ifla6_stats_attrs(skb, idev) < 0)
5840 			goto nla_put_failure;
5841 	}
5842 
5843 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
5844 	if (!nla)
5845 		goto nla_put_failure;
5846 	read_lock_bh(&idev->lock);
5847 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
5848 	read_unlock_bh(&idev->lock);
5849 
5850 	if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE,
5851 		       READ_ONCE(idev->cnf.addr_gen_mode)))
5852 		goto nla_put_failure;
5853 
5854 	ra_mtu = READ_ONCE(idev->ra_mtu);
5855 	if (ra_mtu && nla_put_u32(skb, IFLA_INET6_RA_MTU, ra_mtu))
5856 		goto nla_put_failure;
5857 
5858 	return 0;
5859 
5860 nla_put_failure:
5861 	return -EMSGSIZE;
5862 }
5863 
inet6_get_link_af_size(const struct net_device * dev,u32 ext_filter_mask)5864 static size_t inet6_get_link_af_size(const struct net_device *dev,
5865 				     u32 ext_filter_mask)
5866 {
5867 	if (!__in6_dev_get(dev))
5868 		return 0;
5869 
5870 	return inet6_ifla6_size();
5871 }
5872 
inet6_fill_link_af(struct sk_buff * skb,const struct net_device * dev,u32 ext_filter_mask)5873 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
5874 			      u32 ext_filter_mask)
5875 {
5876 	struct inet6_dev *idev = __in6_dev_get(dev);
5877 
5878 	if (!idev)
5879 		return -ENODATA;
5880 
5881 	if (inet6_fill_ifla6_attrs(skb, idev, ext_filter_mask) < 0)
5882 		return -EMSGSIZE;
5883 
5884 	return 0;
5885 }
5886 
inet6_set_iftoken(struct inet6_dev * idev,struct in6_addr * token,struct netlink_ext_ack * extack)5887 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token,
5888 			     struct netlink_ext_ack *extack)
5889 {
5890 	struct inet6_ifaddr *ifp;
5891 	struct net_device *dev = idev->dev;
5892 	bool clear_token, update_rs = false;
5893 	struct in6_addr ll_addr;
5894 
5895 	ASSERT_RTNL();
5896 
5897 	if (!token)
5898 		return -EINVAL;
5899 
5900 	if (dev->flags & IFF_LOOPBACK) {
5901 		NL_SET_ERR_MSG_MOD(extack, "Device is loopback");
5902 		return -EINVAL;
5903 	}
5904 
5905 	if (dev->flags & IFF_NOARP) {
5906 		NL_SET_ERR_MSG_MOD(extack,
5907 				   "Device does not do neighbour discovery");
5908 		return -EINVAL;
5909 	}
5910 
5911 	if (!ipv6_accept_ra(idev)) {
5912 		NL_SET_ERR_MSG_MOD(extack,
5913 				   "Router advertisement is disabled on device");
5914 		return -EINVAL;
5915 	}
5916 
5917 	if (READ_ONCE(idev->cnf.rtr_solicits) == 0) {
5918 		NL_SET_ERR_MSG(extack,
5919 			       "Router solicitation is disabled on device");
5920 		return -EINVAL;
5921 	}
5922 
5923 	write_lock_bh(&idev->lock);
5924 
5925 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
5926 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
5927 
5928 	write_unlock_bh(&idev->lock);
5929 
5930 	clear_token = ipv6_addr_any(token);
5931 	if (clear_token)
5932 		goto update_lft;
5933 
5934 	if (!idev->dead && (idev->if_flags & IF_READY) &&
5935 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
5936 			     IFA_F_OPTIMISTIC)) {
5937 		/* If we're not ready, then normal ifup will take care
5938 		 * of this. Otherwise, we need to request our rs here.
5939 		 */
5940 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
5941 		update_rs = true;
5942 	}
5943 
5944 update_lft:
5945 	write_lock_bh(&idev->lock);
5946 
5947 	if (update_rs) {
5948 		idev->if_flags |= IF_RS_SENT;
5949 		idev->rs_interval = rfc3315_s14_backoff_init(
5950 			READ_ONCE(idev->cnf.rtr_solicit_interval));
5951 		idev->rs_probes = 1;
5952 		addrconf_mod_rs_timer(idev, idev->rs_interval);
5953 	}
5954 
5955 	/* Well, that's kinda nasty ... */
5956 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
5957 		spin_lock(&ifp->lock);
5958 		if (ifp->tokenized) {
5959 			ifp->valid_lft = 0;
5960 			ifp->prefered_lft = 0;
5961 		}
5962 		spin_unlock(&ifp->lock);
5963 	}
5964 
5965 	write_unlock_bh(&idev->lock);
5966 	inet6_ifinfo_notify(RTM_NEWLINK, idev);
5967 	addrconf_verify_rtnl(dev_net(dev));
5968 	return 0;
5969 }
5970 
5971 static const struct nla_policy inet6_af_policy[IFLA_INET6_MAX + 1] = {
5972 	[IFLA_INET6_ADDR_GEN_MODE]	= { .type = NLA_U8 },
5973 	[IFLA_INET6_TOKEN]		= { .len = sizeof(struct in6_addr) },
5974 	[IFLA_INET6_RA_MTU]		= { .type = NLA_REJECT,
5975 					    .reject_message =
5976 						"IFLA_INET6_RA_MTU can not be set" },
5977 };
5978 
check_addr_gen_mode(int mode)5979 static int check_addr_gen_mode(int mode)
5980 {
5981 	if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
5982 	    mode != IN6_ADDR_GEN_MODE_NONE &&
5983 	    mode != IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5984 	    mode != IN6_ADDR_GEN_MODE_RANDOM)
5985 		return -EINVAL;
5986 	return 1;
5987 }
5988 
check_stable_privacy(struct inet6_dev * idev,struct net * net,int mode)5989 static int check_stable_privacy(struct inet6_dev *idev, struct net *net,
5990 				int mode)
5991 {
5992 	if (mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5993 	    !idev->cnf.stable_secret.initialized &&
5994 	    !net->ipv6.devconf_dflt->stable_secret.initialized)
5995 		return -EINVAL;
5996 	return 1;
5997 }
5998 
inet6_validate_link_af(const struct net_device * dev,const struct nlattr * nla,struct netlink_ext_ack * extack)5999 static int inet6_validate_link_af(const struct net_device *dev,
6000 				  const struct nlattr *nla,
6001 				  struct netlink_ext_ack *extack)
6002 {
6003 	struct nlattr *tb[IFLA_INET6_MAX + 1];
6004 	struct inet6_dev *idev = NULL;
6005 	int err;
6006 
6007 	if (dev) {
6008 		idev = __in6_dev_get(dev);
6009 		if (!idev)
6010 			return -EAFNOSUPPORT;
6011 	}
6012 
6013 	err = nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla,
6014 					  inet6_af_policy, extack);
6015 	if (err)
6016 		return err;
6017 
6018 	if (!tb[IFLA_INET6_TOKEN] && !tb[IFLA_INET6_ADDR_GEN_MODE])
6019 		return -EINVAL;
6020 
6021 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
6022 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
6023 
6024 		if (check_addr_gen_mode(mode) < 0)
6025 			return -EINVAL;
6026 		if (dev && check_stable_privacy(idev, dev_net(dev), mode) < 0)
6027 			return -EINVAL;
6028 	}
6029 
6030 	return 0;
6031 }
6032 
inet6_set_link_af(struct net_device * dev,const struct nlattr * nla,struct netlink_ext_ack * extack)6033 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla,
6034 			     struct netlink_ext_ack *extack)
6035 {
6036 	struct inet6_dev *idev = __in6_dev_get(dev);
6037 	struct nlattr *tb[IFLA_INET6_MAX + 1];
6038 	int err;
6039 
6040 	if (!idev)
6041 		return -EAFNOSUPPORT;
6042 
6043 	if (nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla, NULL, NULL) < 0)
6044 		return -EINVAL;
6045 
6046 	if (tb[IFLA_INET6_TOKEN]) {
6047 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]),
6048 					extack);
6049 		if (err)
6050 			return err;
6051 	}
6052 
6053 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
6054 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
6055 
6056 		WRITE_ONCE(idev->cnf.addr_gen_mode, mode);
6057 	}
6058 
6059 	return 0;
6060 }
6061 
inet6_fill_ifinfo(struct sk_buff * skb,struct inet6_dev * idev,u32 portid,u32 seq,int event,unsigned int flags)6062 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
6063 			     u32 portid, u32 seq, int event, unsigned int flags)
6064 {
6065 	struct net_device *dev = idev->dev;
6066 	struct ifinfomsg *hdr;
6067 	struct nlmsghdr *nlh;
6068 	int ifindex, iflink;
6069 	void *protoinfo;
6070 
6071 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
6072 	if (!nlh)
6073 		return -EMSGSIZE;
6074 
6075 	hdr = nlmsg_data(nlh);
6076 	hdr->ifi_family = AF_INET6;
6077 	hdr->__ifi_pad = 0;
6078 	hdr->ifi_type = dev->type;
6079 	ifindex = READ_ONCE(dev->ifindex);
6080 	hdr->ifi_index = ifindex;
6081 	hdr->ifi_flags = netif_get_flags(dev);
6082 	hdr->ifi_change = 0;
6083 
6084 	iflink = dev_get_iflink(dev);
6085 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
6086 	    (dev->addr_len &&
6087 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
6088 	    nla_put_u32(skb, IFLA_MTU, READ_ONCE(dev->mtu)) ||
6089 	    (ifindex != iflink &&
6090 	     nla_put_u32(skb, IFLA_LINK, iflink)) ||
6091 	    nla_put_u8(skb, IFLA_OPERSTATE,
6092 		       netif_running(dev) ? READ_ONCE(dev->operstate) : IF_OPER_DOWN))
6093 		goto nla_put_failure;
6094 	protoinfo = nla_nest_start_noflag(skb, IFLA_PROTINFO);
6095 	if (!protoinfo)
6096 		goto nla_put_failure;
6097 
6098 	if (inet6_fill_ifla6_attrs(skb, idev, 0) < 0)
6099 		goto nla_put_failure;
6100 
6101 	nla_nest_end(skb, protoinfo);
6102 	nlmsg_end(skb, nlh);
6103 	return 0;
6104 
6105 nla_put_failure:
6106 	nlmsg_cancel(skb, nlh);
6107 	return -EMSGSIZE;
6108 }
6109 
inet6_valid_dump_ifinfo(const struct nlmsghdr * nlh,struct netlink_ext_ack * extack)6110 static int inet6_valid_dump_ifinfo(const struct nlmsghdr *nlh,
6111 				   struct netlink_ext_ack *extack)
6112 {
6113 	struct ifinfomsg *ifm;
6114 
6115 	ifm = nlmsg_payload(nlh, sizeof(*ifm));
6116 	if (!ifm) {
6117 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for link dump request");
6118 		return -EINVAL;
6119 	}
6120 
6121 	if (nlmsg_attrlen(nlh, sizeof(*ifm))) {
6122 		NL_SET_ERR_MSG_MOD(extack, "Invalid data after header");
6123 		return -EINVAL;
6124 	}
6125 
6126 	if (ifm->__ifi_pad || ifm->ifi_type || ifm->ifi_flags ||
6127 	    ifm->ifi_change || ifm->ifi_index) {
6128 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for dump request");
6129 		return -EINVAL;
6130 	}
6131 
6132 	return 0;
6133 }
6134 
inet6_dump_ifinfo(struct sk_buff * skb,struct netlink_callback * cb)6135 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
6136 {
6137 	struct net *net = sock_net(skb->sk);
6138 	struct {
6139 		unsigned long ifindex;
6140 	} *ctx = (void *)cb->ctx;
6141 	struct net_device *dev;
6142 	struct inet6_dev *idev;
6143 	int err;
6144 
6145 	/* only requests using strict checking can pass data to
6146 	 * influence the dump
6147 	 */
6148 	if (cb->strict_check) {
6149 		err = inet6_valid_dump_ifinfo(cb->nlh, cb->extack);
6150 
6151 		if (err < 0)
6152 			return err;
6153 	}
6154 
6155 	err = 0;
6156 	rcu_read_lock();
6157 	for_each_netdev_dump(net, dev, ctx->ifindex) {
6158 		idev = __in6_dev_get(dev);
6159 		if (!idev)
6160 			continue;
6161 		err = inet6_fill_ifinfo(skb, idev,
6162 					NETLINK_CB(cb->skb).portid,
6163 					cb->nlh->nlmsg_seq,
6164 					RTM_NEWLINK, NLM_F_MULTI);
6165 		if (err < 0)
6166 			break;
6167 	}
6168 	rcu_read_unlock();
6169 
6170 	return err;
6171 }
6172 
inet6_ifinfo_notify(int event,struct inet6_dev * idev)6173 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
6174 {
6175 	struct sk_buff *skb;
6176 	struct net *net = dev_net(idev->dev);
6177 	int err = -ENOBUFS;
6178 
6179 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
6180 	if (!skb)
6181 		goto errout;
6182 
6183 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
6184 	if (err < 0) {
6185 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
6186 		WARN_ON(err == -EMSGSIZE);
6187 		kfree_skb(skb);
6188 		goto errout;
6189 	}
6190 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
6191 	return;
6192 errout:
6193 	rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
6194 }
6195 
inet6_prefix_nlmsg_size(void)6196 static inline size_t inet6_prefix_nlmsg_size(void)
6197 {
6198 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
6199 	       + nla_total_size(sizeof(struct in6_addr))
6200 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
6201 }
6202 
inet6_fill_prefix(struct sk_buff * skb,struct inet6_dev * idev,struct prefix_info * pinfo,u32 portid,u32 seq,int event,unsigned int flags)6203 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
6204 			     struct prefix_info *pinfo, u32 portid, u32 seq,
6205 			     int event, unsigned int flags)
6206 {
6207 	struct prefixmsg *pmsg;
6208 	struct nlmsghdr *nlh;
6209 	struct prefix_cacheinfo	ci;
6210 
6211 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
6212 	if (!nlh)
6213 		return -EMSGSIZE;
6214 
6215 	pmsg = nlmsg_data(nlh);
6216 	pmsg->prefix_family = AF_INET6;
6217 	pmsg->prefix_pad1 = 0;
6218 	pmsg->prefix_pad2 = 0;
6219 	pmsg->prefix_ifindex = idev->dev->ifindex;
6220 	pmsg->prefix_len = pinfo->prefix_len;
6221 	pmsg->prefix_type = pinfo->type;
6222 	pmsg->prefix_pad3 = 0;
6223 	pmsg->prefix_flags = pinfo->flags;
6224 
6225 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
6226 		goto nla_put_failure;
6227 	ci.preferred_time = ntohl(pinfo->prefered);
6228 	ci.valid_time = ntohl(pinfo->valid);
6229 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
6230 		goto nla_put_failure;
6231 	nlmsg_end(skb, nlh);
6232 	return 0;
6233 
6234 nla_put_failure:
6235 	nlmsg_cancel(skb, nlh);
6236 	return -EMSGSIZE;
6237 }
6238 
inet6_prefix_notify(int event,struct inet6_dev * idev,struct prefix_info * pinfo)6239 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
6240 			 struct prefix_info *pinfo)
6241 {
6242 	struct sk_buff *skb;
6243 	struct net *net = dev_net(idev->dev);
6244 	int err = -ENOBUFS;
6245 
6246 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
6247 	if (!skb)
6248 		goto errout;
6249 
6250 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
6251 	if (err < 0) {
6252 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
6253 		WARN_ON(err == -EMSGSIZE);
6254 		kfree_skb(skb);
6255 		goto errout;
6256 	}
6257 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
6258 	return;
6259 errout:
6260 	rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
6261 }
6262 
__ipv6_ifa_notify(int event,struct inet6_ifaddr * ifp)6263 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
6264 {
6265 	struct net *net = dev_net(ifp->idev->dev);
6266 
6267 	if (event)
6268 		ASSERT_RTNL();
6269 
6270 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
6271 
6272 	switch (event) {
6273 	case RTM_NEWADDR:
6274 		/*
6275 		 * If the address was optimistic we inserted the route at the
6276 		 * start of our DAD process, so we don't need to do it again.
6277 		 * If the device was taken down in the middle of the DAD
6278 		 * cycle there is a race where we could get here without a
6279 		 * host route, so nothing to insert. That will be fixed when
6280 		 * the device is brought up.
6281 		 */
6282 		if (ifp->rt && !rcu_access_pointer(ifp->rt->fib6_node)) {
6283 			ip6_ins_rt(net, ifp->rt);
6284 		} else if (!ifp->rt && (ifp->idev->dev->flags & IFF_UP)) {
6285 			pr_warn("BUG: Address %pI6c on device %s is missing its host route.\n",
6286 				&ifp->addr, ifp->idev->dev->name);
6287 		}
6288 
6289 		if (ifp->idev->cnf.forwarding)
6290 			addrconf_join_anycast(ifp);
6291 		if (!ipv6_addr_any(&ifp->peer_addr))
6292 			addrconf_prefix_route(&ifp->peer_addr, 128,
6293 					      ifp->rt_priority, ifp->idev->dev,
6294 					      0, 0, GFP_ATOMIC);
6295 		break;
6296 	case RTM_DELADDR:
6297 		if (ifp->idev->cnf.forwarding)
6298 			addrconf_leave_anycast(ifp);
6299 		addrconf_leave_solict(ifp->idev, &ifp->addr);
6300 		if (!ipv6_addr_any(&ifp->peer_addr)) {
6301 			struct fib6_info *rt;
6302 
6303 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
6304 						       ifp->idev->dev, 0, 0,
6305 						       false);
6306 			if (rt)
6307 				ip6_del_rt(net, rt, false);
6308 		}
6309 		if (ifp->rt) {
6310 			ip6_del_rt(net, ifp->rt, false);
6311 			ifp->rt = NULL;
6312 		}
6313 		rt_genid_bump_ipv6(net);
6314 		break;
6315 	}
6316 	atomic_inc(&net->ipv6.dev_addr_genid);
6317 }
6318 
ipv6_ifa_notify(int event,struct inet6_ifaddr * ifp)6319 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
6320 {
6321 	if (likely(ifp->idev->dead == 0))
6322 		__ipv6_ifa_notify(event, ifp);
6323 }
6324 
6325 #ifdef CONFIG_SYSCTL
6326 
addrconf_sysctl_forward(const struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)6327 static int addrconf_sysctl_forward(const struct ctl_table *ctl, int write,
6328 		void *buffer, size_t *lenp, loff_t *ppos)
6329 {
6330 	int *valp = ctl->data;
6331 	int val = *valp;
6332 	loff_t pos = *ppos;
6333 	struct ctl_table lctl;
6334 	int ret;
6335 
6336 	/*
6337 	 * ctl->data points to idev->cnf.forwarding, we should
6338 	 * not modify it until we get the rtnl lock.
6339 	 */
6340 	lctl = *ctl;
6341 	lctl.data = &val;
6342 
6343 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6344 
6345 	if (write)
6346 		ret = addrconf_fixup_forwarding(ctl, valp, val);
6347 	if (ret)
6348 		*ppos = pos;
6349 	return ret;
6350 }
6351 
addrconf_sysctl_mtu(const struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)6352 static int addrconf_sysctl_mtu(const struct ctl_table *ctl, int write,
6353 		void *buffer, size_t *lenp, loff_t *ppos)
6354 {
6355 	struct inet6_dev *idev = ctl->extra1;
6356 	int min_mtu = IPV6_MIN_MTU;
6357 	struct ctl_table lctl;
6358 
6359 	lctl = *ctl;
6360 	lctl.extra1 = &min_mtu;
6361 	lctl.extra2 = idev ? &idev->dev->mtu : NULL;
6362 
6363 	return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
6364 }
6365 
dev_disable_change(struct inet6_dev * idev)6366 static void dev_disable_change(struct inet6_dev *idev)
6367 {
6368 	struct netdev_notifier_info info;
6369 
6370 	if (!idev || !idev->dev)
6371 		return;
6372 
6373 	netdev_notifier_info_init(&info, idev->dev);
6374 	if (idev->cnf.disable_ipv6)
6375 		addrconf_notify(NULL, NETDEV_DOWN, &info);
6376 	else
6377 		addrconf_notify(NULL, NETDEV_UP, &info);
6378 }
6379 
addrconf_disable_change(struct net * net,__s32 newf)6380 static void addrconf_disable_change(struct net *net, __s32 newf)
6381 {
6382 	struct net_device *dev;
6383 	struct inet6_dev *idev;
6384 
6385 	for_each_netdev(net, dev) {
6386 		idev = __in6_dev_get_rtnl_net(dev);
6387 		if (idev) {
6388 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
6389 
6390 			WRITE_ONCE(idev->cnf.disable_ipv6, newf);
6391 			if (changed)
6392 				dev_disable_change(idev);
6393 		}
6394 	}
6395 }
6396 
addrconf_disable_ipv6(const struct ctl_table * table,int * p,int newf)6397 static int addrconf_disable_ipv6(const struct ctl_table *table, int *p, int newf)
6398 {
6399 	struct net *net = (struct net *)table->extra2;
6400 	int old;
6401 
6402 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
6403 		WRITE_ONCE(*p, newf);
6404 		return 0;
6405 	}
6406 
6407 	if (!rtnl_net_trylock(net))
6408 		return restart_syscall();
6409 
6410 	old = *p;
6411 	WRITE_ONCE(*p, newf);
6412 
6413 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
6414 		WRITE_ONCE(net->ipv6.devconf_dflt->disable_ipv6, newf);
6415 		addrconf_disable_change(net, newf);
6416 	} else if ((!newf) ^ (!old)) {
6417 		dev_disable_change((struct inet6_dev *)table->extra1);
6418 	}
6419 
6420 	rtnl_net_unlock(net);
6421 	return 0;
6422 }
6423 
addrconf_sysctl_disable(const struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)6424 static int addrconf_sysctl_disable(const struct ctl_table *ctl, int write,
6425 		void *buffer, size_t *lenp, loff_t *ppos)
6426 {
6427 	int *valp = ctl->data;
6428 	int val = *valp;
6429 	loff_t pos = *ppos;
6430 	struct ctl_table lctl;
6431 	int ret;
6432 
6433 	/*
6434 	 * ctl->data points to idev->cnf.disable_ipv6, we should
6435 	 * not modify it until we get the rtnl lock.
6436 	 */
6437 	lctl = *ctl;
6438 	lctl.data = &val;
6439 
6440 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6441 
6442 	if (write)
6443 		ret = addrconf_disable_ipv6(ctl, valp, val);
6444 	if (ret)
6445 		*ppos = pos;
6446 	return ret;
6447 }
6448 
addrconf_sysctl_proxy_ndp(const struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)6449 static int addrconf_sysctl_proxy_ndp(const struct ctl_table *ctl, int write,
6450 		void *buffer, size_t *lenp, loff_t *ppos)
6451 {
6452 	int *valp = ctl->data;
6453 	int ret;
6454 	int old, new;
6455 
6456 	old = *valp;
6457 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
6458 	new = *valp;
6459 
6460 	if (write && old != new) {
6461 		struct net *net = ctl->extra2;
6462 
6463 		if (!rtnl_net_trylock(net))
6464 			return restart_syscall();
6465 
6466 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp) {
6467 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6468 						     NETCONFA_PROXY_NEIGH,
6469 						     NETCONFA_IFINDEX_DEFAULT,
6470 						     net->ipv6.devconf_dflt);
6471 		} else if (valp == &net->ipv6.devconf_all->proxy_ndp) {
6472 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6473 						     NETCONFA_PROXY_NEIGH,
6474 						     NETCONFA_IFINDEX_ALL,
6475 						     net->ipv6.devconf_all);
6476 		} else {
6477 			struct inet6_dev *idev = ctl->extra1;
6478 
6479 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6480 						     NETCONFA_PROXY_NEIGH,
6481 						     idev->dev->ifindex,
6482 						     &idev->cnf);
6483 		}
6484 		rtnl_net_unlock(net);
6485 	}
6486 
6487 	return ret;
6488 }
6489 
addrconf_sysctl_addr_gen_mode(const struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)6490 static int addrconf_sysctl_addr_gen_mode(const struct ctl_table *ctl, int write,
6491 					 void *buffer, size_t *lenp,
6492 					 loff_t *ppos)
6493 {
6494 	int ret = 0;
6495 	u32 new_val;
6496 	struct inet6_dev *idev = (struct inet6_dev *)ctl->extra1;
6497 	struct net *net = (struct net *)ctl->extra2;
6498 	struct ctl_table tmp = {
6499 		.data = &new_val,
6500 		.maxlen = sizeof(new_val),
6501 		.mode = ctl->mode,
6502 	};
6503 
6504 	if (!rtnl_net_trylock(net))
6505 		return restart_syscall();
6506 
6507 	new_val = *((u32 *)ctl->data);
6508 
6509 	ret = proc_douintvec(&tmp, write, buffer, lenp, ppos);
6510 	if (ret != 0)
6511 		goto out;
6512 
6513 	if (write) {
6514 		if (check_addr_gen_mode(new_val) < 0) {
6515 			ret = -EINVAL;
6516 			goto out;
6517 		}
6518 
6519 		if (idev) {
6520 			if (check_stable_privacy(idev, net, new_val) < 0) {
6521 				ret = -EINVAL;
6522 				goto out;
6523 			}
6524 
6525 			if (idev->cnf.addr_gen_mode != new_val) {
6526 				WRITE_ONCE(idev->cnf.addr_gen_mode, new_val);
6527 				netdev_lock_ops(idev->dev);
6528 				addrconf_init_auto_addrs(idev->dev);
6529 				netdev_unlock_ops(idev->dev);
6530 			}
6531 		} else if (&net->ipv6.devconf_all->addr_gen_mode == ctl->data) {
6532 			struct net_device *dev;
6533 
6534 			WRITE_ONCE(net->ipv6.devconf_dflt->addr_gen_mode, new_val);
6535 			for_each_netdev(net, dev) {
6536 				idev = __in6_dev_get_rtnl_net(dev);
6537 				if (idev &&
6538 				    idev->cnf.addr_gen_mode != new_val) {
6539 					WRITE_ONCE(idev->cnf.addr_gen_mode,
6540 						  new_val);
6541 					netdev_lock_ops(idev->dev);
6542 					addrconf_init_auto_addrs(idev->dev);
6543 					netdev_unlock_ops(idev->dev);
6544 				}
6545 			}
6546 		}
6547 
6548 		WRITE_ONCE(*((u32 *)ctl->data), new_val);
6549 	}
6550 
6551 out:
6552 	rtnl_net_unlock(net);
6553 
6554 	return ret;
6555 }
6556 
addrconf_sysctl_stable_secret(const struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)6557 static int addrconf_sysctl_stable_secret(const struct ctl_table *ctl, int write,
6558 					 void *buffer, size_t *lenp,
6559 					 loff_t *ppos)
6560 {
6561 	int err;
6562 	struct in6_addr addr;
6563 	char str[IPV6_MAX_STRLEN];
6564 	struct ctl_table lctl = *ctl;
6565 	struct net *net = ctl->extra2;
6566 	struct ipv6_stable_secret *secret = ctl->data;
6567 
6568 	if (&net->ipv6.devconf_all->stable_secret == ctl->data)
6569 		return -EIO;
6570 
6571 	lctl.maxlen = IPV6_MAX_STRLEN;
6572 	lctl.data = str;
6573 
6574 	if (!rtnl_net_trylock(net))
6575 		return restart_syscall();
6576 
6577 	if (!write && !secret->initialized) {
6578 		err = -EIO;
6579 		goto out;
6580 	}
6581 
6582 	err = snprintf(str, sizeof(str), "%pI6", &secret->secret);
6583 	if (err >= sizeof(str)) {
6584 		err = -EIO;
6585 		goto out;
6586 	}
6587 
6588 	err = proc_dostring(&lctl, write, buffer, lenp, ppos);
6589 	if (err || !write)
6590 		goto out;
6591 
6592 	if (in6_pton(str, -1, addr.in6_u.u6_addr8, -1, NULL) != 1) {
6593 		err = -EIO;
6594 		goto out;
6595 	}
6596 
6597 	secret->initialized = true;
6598 	secret->secret = addr;
6599 
6600 	if (&net->ipv6.devconf_dflt->stable_secret == ctl->data) {
6601 		struct net_device *dev;
6602 
6603 		for_each_netdev(net, dev) {
6604 			struct inet6_dev *idev = __in6_dev_get_rtnl_net(dev);
6605 
6606 			if (idev) {
6607 				WRITE_ONCE(idev->cnf.addr_gen_mode,
6608 					   IN6_ADDR_GEN_MODE_STABLE_PRIVACY);
6609 			}
6610 		}
6611 	} else {
6612 		struct inet6_dev *idev = ctl->extra1;
6613 
6614 		WRITE_ONCE(idev->cnf.addr_gen_mode,
6615 			   IN6_ADDR_GEN_MODE_STABLE_PRIVACY);
6616 	}
6617 
6618 out:
6619 	rtnl_net_unlock(net);
6620 
6621 	return err;
6622 }
6623 
6624 static
addrconf_sysctl_ignore_routes_with_linkdown(const struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)6625 int addrconf_sysctl_ignore_routes_with_linkdown(const struct ctl_table *ctl,
6626 						int write, void *buffer,
6627 						size_t *lenp,
6628 						loff_t *ppos)
6629 {
6630 	int *valp = ctl->data;
6631 	int val = *valp;
6632 	loff_t pos = *ppos;
6633 	struct ctl_table lctl;
6634 	int ret;
6635 
6636 	/* ctl->data points to idev->cnf.ignore_routes_when_linkdown
6637 	 * we should not modify it until we get the rtnl lock.
6638 	 */
6639 	lctl = *ctl;
6640 	lctl.data = &val;
6641 
6642 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6643 
6644 	if (write)
6645 		ret = addrconf_fixup_linkdown(ctl, valp, val);
6646 	if (ret)
6647 		*ppos = pos;
6648 	return ret;
6649 }
6650 
6651 static
addrconf_set_nopolicy(struct rt6_info * rt,int action)6652 void addrconf_set_nopolicy(struct rt6_info *rt, int action)
6653 {
6654 	if (rt) {
6655 		if (action)
6656 			rt->dst.flags |= DST_NOPOLICY;
6657 		else
6658 			rt->dst.flags &= ~DST_NOPOLICY;
6659 	}
6660 }
6661 
6662 static
addrconf_disable_policy_idev(struct inet6_dev * idev,int val)6663 void addrconf_disable_policy_idev(struct inet6_dev *idev, int val)
6664 {
6665 	struct inet6_ifaddr *ifa;
6666 
6667 	read_lock_bh(&idev->lock);
6668 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
6669 		spin_lock(&ifa->lock);
6670 		if (ifa->rt) {
6671 			/* host routes only use builtin fib6_nh */
6672 			struct fib6_nh *nh = ifa->rt->fib6_nh;
6673 			int cpu;
6674 
6675 			rcu_read_lock();
6676 			ifa->rt->dst_nopolicy = val ? true : false;
6677 			if (nh->rt6i_pcpu) {
6678 				for_each_possible_cpu(cpu) {
6679 					struct rt6_info **rtp;
6680 
6681 					rtp = per_cpu_ptr(nh->rt6i_pcpu, cpu);
6682 					addrconf_set_nopolicy(*rtp, val);
6683 				}
6684 			}
6685 			rcu_read_unlock();
6686 		}
6687 		spin_unlock(&ifa->lock);
6688 	}
6689 	read_unlock_bh(&idev->lock);
6690 }
6691 
6692 static
addrconf_disable_policy(const struct ctl_table * ctl,int * valp,int val)6693 int addrconf_disable_policy(const struct ctl_table *ctl, int *valp, int val)
6694 {
6695 	struct net *net = (struct net *)ctl->extra2;
6696 	struct inet6_dev *idev;
6697 
6698 	if (valp == &net->ipv6.devconf_dflt->disable_policy) {
6699 		WRITE_ONCE(*valp, val);
6700 		return 0;
6701 	}
6702 
6703 	if (!rtnl_net_trylock(net))
6704 		return restart_syscall();
6705 
6706 	WRITE_ONCE(*valp, val);
6707 
6708 	if (valp == &net->ipv6.devconf_all->disable_policy)  {
6709 		struct net_device *dev;
6710 
6711 		for_each_netdev(net, dev) {
6712 			idev = __in6_dev_get_rtnl_net(dev);
6713 			if (idev)
6714 				addrconf_disable_policy_idev(idev, val);
6715 		}
6716 	} else {
6717 		idev = (struct inet6_dev *)ctl->extra1;
6718 		addrconf_disable_policy_idev(idev, val);
6719 	}
6720 
6721 	rtnl_net_unlock(net);
6722 	return 0;
6723 }
6724 
addrconf_sysctl_disable_policy(const struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)6725 static int addrconf_sysctl_disable_policy(const struct ctl_table *ctl, int write,
6726 				   void *buffer, size_t *lenp, loff_t *ppos)
6727 {
6728 	int *valp = ctl->data;
6729 	int val = *valp;
6730 	loff_t pos = *ppos;
6731 	struct ctl_table lctl;
6732 	int ret;
6733 
6734 	lctl = *ctl;
6735 	lctl.data = &val;
6736 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6737 
6738 	if (write && (*valp != val))
6739 		ret = addrconf_disable_policy(ctl, valp, val);
6740 
6741 	if (ret)
6742 		*ppos = pos;
6743 
6744 	return ret;
6745 }
6746 
addrconf_force_forward_change(struct net * net,__s32 newf)6747 static void addrconf_force_forward_change(struct net *net, __s32 newf)
6748 {
6749 	struct net_device *dev;
6750 	struct inet6_dev *idev;
6751 
6752 	for_each_netdev(net, dev) {
6753 		idev = __in6_dev_get_rtnl_net(dev);
6754 		if (idev) {
6755 			int changed = (!idev->cnf.force_forwarding) ^ (!newf);
6756 
6757 			WRITE_ONCE(idev->cnf.force_forwarding, newf);
6758 			if (changed)
6759 				inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
6760 							     NETCONFA_FORCE_FORWARDING,
6761 							     dev->ifindex, &idev->cnf);
6762 		}
6763 	}
6764 }
6765 
addrconf_sysctl_force_forwarding(const struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)6766 static int addrconf_sysctl_force_forwarding(const struct ctl_table *ctl, int write,
6767 					    void *buffer, size_t *lenp, loff_t *ppos)
6768 {
6769 	struct inet6_dev *idev = ctl->extra1;
6770 	struct ctl_table tmp_ctl = *ctl;
6771 	struct net *net = ctl->extra2;
6772 	int *valp = ctl->data;
6773 	int new_val = *valp;
6774 	int old_val = *valp;
6775 	loff_t pos = *ppos;
6776 	int ret;
6777 
6778 	tmp_ctl.extra1 = SYSCTL_ZERO;
6779 	tmp_ctl.extra2 = SYSCTL_ONE;
6780 	tmp_ctl.data = &new_val;
6781 
6782 	ret = proc_douintvec_minmax(&tmp_ctl, write, buffer, lenp, ppos);
6783 
6784 	if (write && old_val != new_val) {
6785 		if (!rtnl_net_trylock(net))
6786 			return restart_syscall();
6787 
6788 		WRITE_ONCE(*valp, new_val);
6789 
6790 		if (valp == &net->ipv6.devconf_dflt->force_forwarding) {
6791 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6792 						     NETCONFA_FORCE_FORWARDING,
6793 						     NETCONFA_IFINDEX_DEFAULT,
6794 						     net->ipv6.devconf_dflt);
6795 		} else if (valp == &net->ipv6.devconf_all->force_forwarding) {
6796 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6797 						     NETCONFA_FORCE_FORWARDING,
6798 						     NETCONFA_IFINDEX_ALL,
6799 						     net->ipv6.devconf_all);
6800 
6801 			addrconf_force_forward_change(net, new_val);
6802 		} else {
6803 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6804 						     NETCONFA_FORCE_FORWARDING,
6805 						     idev->dev->ifindex,
6806 						     &idev->cnf);
6807 		}
6808 		rtnl_net_unlock(net);
6809 	}
6810 
6811 	if (ret)
6812 		*ppos = pos;
6813 	return ret;
6814 }
6815 
6816 static int minus_one = -1;
6817 static const int two_five_five = 255;
6818 static u32 ioam6_if_id_max = U16_MAX;
6819 
6820 static const struct ctl_table addrconf_sysctl[] = {
6821 	{
6822 		.procname	= "forwarding",
6823 		.data		= &ipv6_devconf.forwarding,
6824 		.maxlen		= sizeof(int),
6825 		.mode		= 0644,
6826 		.proc_handler	= addrconf_sysctl_forward,
6827 	},
6828 	{
6829 		.procname	= "hop_limit",
6830 		.data		= &ipv6_devconf.hop_limit,
6831 		.maxlen		= sizeof(int),
6832 		.mode		= 0644,
6833 		.proc_handler	= proc_dointvec_minmax,
6834 		.extra1		= (void *)SYSCTL_ONE,
6835 		.extra2		= (void *)&two_five_five,
6836 	},
6837 	{
6838 		.procname	= "mtu",
6839 		.data		= &ipv6_devconf.mtu6,
6840 		.maxlen		= sizeof(int),
6841 		.mode		= 0644,
6842 		.proc_handler	= addrconf_sysctl_mtu,
6843 	},
6844 	{
6845 		.procname	= "accept_ra",
6846 		.data		= &ipv6_devconf.accept_ra,
6847 		.maxlen		= sizeof(int),
6848 		.mode		= 0644,
6849 		.proc_handler	= proc_dointvec,
6850 	},
6851 	{
6852 		.procname	= "accept_redirects",
6853 		.data		= &ipv6_devconf.accept_redirects,
6854 		.maxlen		= sizeof(int),
6855 		.mode		= 0644,
6856 		.proc_handler	= proc_dointvec,
6857 	},
6858 	{
6859 		.procname	= "autoconf",
6860 		.data		= &ipv6_devconf.autoconf,
6861 		.maxlen		= sizeof(int),
6862 		.mode		= 0644,
6863 		.proc_handler	= proc_dointvec,
6864 	},
6865 	{
6866 		.procname	= "dad_transmits",
6867 		.data		= &ipv6_devconf.dad_transmits,
6868 		.maxlen		= sizeof(int),
6869 		.mode		= 0644,
6870 		.proc_handler	= proc_dointvec,
6871 	},
6872 	{
6873 		.procname	= "router_solicitations",
6874 		.data		= &ipv6_devconf.rtr_solicits,
6875 		.maxlen		= sizeof(int),
6876 		.mode		= 0644,
6877 		.proc_handler	= proc_dointvec_minmax,
6878 		.extra1		= &minus_one,
6879 	},
6880 	{
6881 		.procname	= "router_solicitation_interval",
6882 		.data		= &ipv6_devconf.rtr_solicit_interval,
6883 		.maxlen		= sizeof(int),
6884 		.mode		= 0644,
6885 		.proc_handler	= proc_dointvec_jiffies,
6886 	},
6887 	{
6888 		.procname	= "router_solicitation_max_interval",
6889 		.data		= &ipv6_devconf.rtr_solicit_max_interval,
6890 		.maxlen		= sizeof(int),
6891 		.mode		= 0644,
6892 		.proc_handler	= proc_dointvec_jiffies,
6893 	},
6894 	{
6895 		.procname	= "router_solicitation_delay",
6896 		.data		= &ipv6_devconf.rtr_solicit_delay,
6897 		.maxlen		= sizeof(int),
6898 		.mode		= 0644,
6899 		.proc_handler	= proc_dointvec_jiffies,
6900 	},
6901 	{
6902 		.procname	= "force_mld_version",
6903 		.data		= &ipv6_devconf.force_mld_version,
6904 		.maxlen		= sizeof(int),
6905 		.mode		= 0644,
6906 		.proc_handler	= proc_dointvec,
6907 	},
6908 	{
6909 		.procname	= "mldv1_unsolicited_report_interval",
6910 		.data		=
6911 			&ipv6_devconf.mldv1_unsolicited_report_interval,
6912 		.maxlen		= sizeof(int),
6913 		.mode		= 0644,
6914 		.proc_handler	= proc_dointvec_ms_jiffies,
6915 	},
6916 	{
6917 		.procname	= "mldv2_unsolicited_report_interval",
6918 		.data		=
6919 			&ipv6_devconf.mldv2_unsolicited_report_interval,
6920 		.maxlen		= sizeof(int),
6921 		.mode		= 0644,
6922 		.proc_handler	= proc_dointvec_ms_jiffies,
6923 	},
6924 	{
6925 		.procname	= "use_tempaddr",
6926 		.data		= &ipv6_devconf.use_tempaddr,
6927 		.maxlen		= sizeof(int),
6928 		.mode		= 0644,
6929 		.proc_handler	= proc_dointvec,
6930 	},
6931 	{
6932 		.procname	= "temp_valid_lft",
6933 		.data		= &ipv6_devconf.temp_valid_lft,
6934 		.maxlen		= sizeof(int),
6935 		.mode		= 0644,
6936 		.proc_handler	= proc_dointvec,
6937 	},
6938 	{
6939 		.procname	= "temp_prefered_lft",
6940 		.data		= &ipv6_devconf.temp_prefered_lft,
6941 		.maxlen		= sizeof(int),
6942 		.mode		= 0644,
6943 		.proc_handler	= proc_dointvec,
6944 	},
6945 	{
6946 		.procname       = "regen_min_advance",
6947 		.data           = &ipv6_devconf.regen_min_advance,
6948 		.maxlen         = sizeof(int),
6949 		.mode           = 0644,
6950 		.proc_handler   = proc_dointvec,
6951 	},
6952 	{
6953 		.procname	= "regen_max_retry",
6954 		.data		= &ipv6_devconf.regen_max_retry,
6955 		.maxlen		= sizeof(int),
6956 		.mode		= 0644,
6957 		.proc_handler	= proc_dointvec,
6958 	},
6959 	{
6960 		.procname	= "max_desync_factor",
6961 		.data		= &ipv6_devconf.max_desync_factor,
6962 		.maxlen		= sizeof(int),
6963 		.mode		= 0644,
6964 		.proc_handler	= proc_dointvec,
6965 	},
6966 	{
6967 		.procname	= "max_addresses",
6968 		.data		= &ipv6_devconf.max_addresses,
6969 		.maxlen		= sizeof(int),
6970 		.mode		= 0644,
6971 		.proc_handler	= proc_dointvec,
6972 	},
6973 	{
6974 		.procname	= "accept_ra_defrtr",
6975 		.data		= &ipv6_devconf.accept_ra_defrtr,
6976 		.maxlen		= sizeof(int),
6977 		.mode		= 0644,
6978 		.proc_handler	= proc_dointvec,
6979 	},
6980 	{
6981 		.procname	= "ra_defrtr_metric",
6982 		.data		= &ipv6_devconf.ra_defrtr_metric,
6983 		.maxlen		= sizeof(u32),
6984 		.mode		= 0644,
6985 		.proc_handler	= proc_douintvec_minmax,
6986 		.extra1		= (void *)SYSCTL_ONE,
6987 	},
6988 	{
6989 		.procname	= "accept_ra_min_hop_limit",
6990 		.data		= &ipv6_devconf.accept_ra_min_hop_limit,
6991 		.maxlen		= sizeof(int),
6992 		.mode		= 0644,
6993 		.proc_handler	= proc_dointvec,
6994 	},
6995 	{
6996 		.procname	= "accept_ra_min_lft",
6997 		.data		= &ipv6_devconf.accept_ra_min_lft,
6998 		.maxlen		= sizeof(int),
6999 		.mode		= 0644,
7000 		.proc_handler	= proc_dointvec,
7001 	},
7002 	{
7003 		.procname	= "accept_ra_pinfo",
7004 		.data		= &ipv6_devconf.accept_ra_pinfo,
7005 		.maxlen		= sizeof(int),
7006 		.mode		= 0644,
7007 		.proc_handler	= proc_dointvec,
7008 	},
7009 	{
7010 		.procname	= "ra_honor_pio_life",
7011 		.data		= &ipv6_devconf.ra_honor_pio_life,
7012 		.maxlen		= sizeof(u8),
7013 		.mode		= 0644,
7014 		.proc_handler	= proc_dou8vec_minmax,
7015 		.extra1		= SYSCTL_ZERO,
7016 		.extra2		= SYSCTL_ONE,
7017 	},
7018 	{
7019 		.procname	= "ra_honor_pio_pflag",
7020 		.data		= &ipv6_devconf.ra_honor_pio_pflag,
7021 		.maxlen		= sizeof(u8),
7022 		.mode		= 0644,
7023 		.proc_handler	= proc_dou8vec_minmax,
7024 		.extra1		= SYSCTL_ZERO,
7025 		.extra2		= SYSCTL_ONE,
7026 	},
7027 #ifdef CONFIG_IPV6_ROUTER_PREF
7028 	{
7029 		.procname	= "accept_ra_rtr_pref",
7030 		.data		= &ipv6_devconf.accept_ra_rtr_pref,
7031 		.maxlen		= sizeof(int),
7032 		.mode		= 0644,
7033 		.proc_handler	= proc_dointvec,
7034 	},
7035 	{
7036 		.procname	= "router_probe_interval",
7037 		.data		= &ipv6_devconf.rtr_probe_interval,
7038 		.maxlen		= sizeof(int),
7039 		.mode		= 0644,
7040 		.proc_handler	= proc_dointvec_jiffies,
7041 	},
7042 #ifdef CONFIG_IPV6_ROUTE_INFO
7043 	{
7044 		.procname	= "accept_ra_rt_info_min_plen",
7045 		.data		= &ipv6_devconf.accept_ra_rt_info_min_plen,
7046 		.maxlen		= sizeof(int),
7047 		.mode		= 0644,
7048 		.proc_handler	= proc_dointvec,
7049 	},
7050 	{
7051 		.procname	= "accept_ra_rt_info_max_plen",
7052 		.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
7053 		.maxlen		= sizeof(int),
7054 		.mode		= 0644,
7055 		.proc_handler	= proc_dointvec,
7056 	},
7057 #endif
7058 #endif
7059 	{
7060 		.procname	= "proxy_ndp",
7061 		.data		= &ipv6_devconf.proxy_ndp,
7062 		.maxlen		= sizeof(int),
7063 		.mode		= 0644,
7064 		.proc_handler	= addrconf_sysctl_proxy_ndp,
7065 	},
7066 	{
7067 		.procname	= "accept_source_route",
7068 		.data		= &ipv6_devconf.accept_source_route,
7069 		.maxlen		= sizeof(int),
7070 		.mode		= 0644,
7071 		.proc_handler	= proc_dointvec,
7072 	},
7073 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
7074 	{
7075 		.procname	= "optimistic_dad",
7076 		.data		= &ipv6_devconf.optimistic_dad,
7077 		.maxlen		= sizeof(int),
7078 		.mode		= 0644,
7079 		.proc_handler   = proc_dointvec,
7080 	},
7081 	{
7082 		.procname	= "use_optimistic",
7083 		.data		= &ipv6_devconf.use_optimistic,
7084 		.maxlen		= sizeof(int),
7085 		.mode		= 0644,
7086 		.proc_handler	= proc_dointvec,
7087 	},
7088 #endif
7089 #ifdef CONFIG_IPV6_MROUTE
7090 	{
7091 		.procname	= "mc_forwarding",
7092 		.data		= &ipv6_devconf.mc_forwarding,
7093 		.maxlen		= sizeof(int),
7094 		.mode		= 0444,
7095 		.proc_handler	= proc_dointvec,
7096 	},
7097 #endif
7098 	{
7099 		.procname	= "disable_ipv6",
7100 		.data		= &ipv6_devconf.disable_ipv6,
7101 		.maxlen		= sizeof(int),
7102 		.mode		= 0644,
7103 		.proc_handler	= addrconf_sysctl_disable,
7104 	},
7105 	{
7106 		.procname	= "accept_dad",
7107 		.data		= &ipv6_devconf.accept_dad,
7108 		.maxlen		= sizeof(int),
7109 		.mode		= 0644,
7110 		.proc_handler	= proc_dointvec,
7111 	},
7112 	{
7113 		.procname	= "force_tllao",
7114 		.data		= &ipv6_devconf.force_tllao,
7115 		.maxlen		= sizeof(int),
7116 		.mode		= 0644,
7117 		.proc_handler	= proc_dointvec
7118 	},
7119 	{
7120 		.procname	= "ndisc_notify",
7121 		.data		= &ipv6_devconf.ndisc_notify,
7122 		.maxlen		= sizeof(int),
7123 		.mode		= 0644,
7124 		.proc_handler	= proc_dointvec
7125 	},
7126 	{
7127 		.procname	= "suppress_frag_ndisc",
7128 		.data		= &ipv6_devconf.suppress_frag_ndisc,
7129 		.maxlen		= sizeof(int),
7130 		.mode		= 0644,
7131 		.proc_handler	= proc_dointvec
7132 	},
7133 	{
7134 		.procname	= "accept_ra_from_local",
7135 		.data		= &ipv6_devconf.accept_ra_from_local,
7136 		.maxlen		= sizeof(int),
7137 		.mode		= 0644,
7138 		.proc_handler	= proc_dointvec,
7139 	},
7140 	{
7141 		.procname	= "accept_ra_mtu",
7142 		.data		= &ipv6_devconf.accept_ra_mtu,
7143 		.maxlen		= sizeof(int),
7144 		.mode		= 0644,
7145 		.proc_handler	= proc_dointvec,
7146 	},
7147 	{
7148 		.procname	= "stable_secret",
7149 		.data		= &ipv6_devconf.stable_secret,
7150 		.maxlen		= IPV6_MAX_STRLEN,
7151 		.mode		= 0600,
7152 		.proc_handler	= addrconf_sysctl_stable_secret,
7153 	},
7154 	{
7155 		.procname	= "use_oif_addrs_only",
7156 		.data		= &ipv6_devconf.use_oif_addrs_only,
7157 		.maxlen		= sizeof(int),
7158 		.mode		= 0644,
7159 		.proc_handler	= proc_dointvec,
7160 	},
7161 	{
7162 		.procname	= "ignore_routes_with_linkdown",
7163 		.data		= &ipv6_devconf.ignore_routes_with_linkdown,
7164 		.maxlen		= sizeof(int),
7165 		.mode		= 0644,
7166 		.proc_handler	= addrconf_sysctl_ignore_routes_with_linkdown,
7167 	},
7168 	{
7169 		.procname	= "drop_unicast_in_l2_multicast",
7170 		.data		= &ipv6_devconf.drop_unicast_in_l2_multicast,
7171 		.maxlen		= sizeof(int),
7172 		.mode		= 0644,
7173 		.proc_handler	= proc_dointvec,
7174 	},
7175 	{
7176 		.procname	= "drop_unsolicited_na",
7177 		.data		= &ipv6_devconf.drop_unsolicited_na,
7178 		.maxlen		= sizeof(int),
7179 		.mode		= 0644,
7180 		.proc_handler	= proc_dointvec,
7181 	},
7182 	{
7183 		.procname	= "keep_addr_on_down",
7184 		.data		= &ipv6_devconf.keep_addr_on_down,
7185 		.maxlen		= sizeof(int),
7186 		.mode		= 0644,
7187 		.proc_handler	= proc_dointvec,
7188 
7189 	},
7190 	{
7191 		.procname	= "seg6_enabled",
7192 		.data		= &ipv6_devconf.seg6_enabled,
7193 		.maxlen		= sizeof(int),
7194 		.mode		= 0644,
7195 		.proc_handler	= proc_dointvec,
7196 	},
7197 #ifdef CONFIG_IPV6_SEG6_HMAC
7198 	{
7199 		.procname	= "seg6_require_hmac",
7200 		.data		= &ipv6_devconf.seg6_require_hmac,
7201 		.maxlen		= sizeof(int),
7202 		.mode		= 0644,
7203 		.proc_handler	= proc_dointvec,
7204 	},
7205 #endif
7206 	{
7207 		.procname       = "enhanced_dad",
7208 		.data           = &ipv6_devconf.enhanced_dad,
7209 		.maxlen         = sizeof(int),
7210 		.mode           = 0644,
7211 		.proc_handler   = proc_dointvec,
7212 	},
7213 	{
7214 		.procname	= "addr_gen_mode",
7215 		.data		= &ipv6_devconf.addr_gen_mode,
7216 		.maxlen		= sizeof(int),
7217 		.mode		= 0644,
7218 		.proc_handler	= addrconf_sysctl_addr_gen_mode,
7219 	},
7220 	{
7221 		.procname       = "disable_policy",
7222 		.data           = &ipv6_devconf.disable_policy,
7223 		.maxlen         = sizeof(int),
7224 		.mode           = 0644,
7225 		.proc_handler   = addrconf_sysctl_disable_policy,
7226 	},
7227 	{
7228 		.procname	= "ndisc_tclass",
7229 		.data		= &ipv6_devconf.ndisc_tclass,
7230 		.maxlen		= sizeof(int),
7231 		.mode		= 0644,
7232 		.proc_handler	= proc_dointvec_minmax,
7233 		.extra1		= (void *)SYSCTL_ZERO,
7234 		.extra2		= (void *)&two_five_five,
7235 	},
7236 	{
7237 		.procname	= "rpl_seg_enabled",
7238 		.data		= &ipv6_devconf.rpl_seg_enabled,
7239 		.maxlen		= sizeof(int),
7240 		.mode		= 0644,
7241 		.proc_handler	= proc_dointvec,
7242 	},
7243 	{
7244 		.procname	= "ioam6_enabled",
7245 		.data		= &ipv6_devconf.ioam6_enabled,
7246 		.maxlen		= sizeof(u8),
7247 		.mode		= 0644,
7248 		.proc_handler	= proc_dou8vec_minmax,
7249 		.extra1		= (void *)SYSCTL_ZERO,
7250 		.extra2		= (void *)SYSCTL_ONE,
7251 	},
7252 	{
7253 		.procname	= "ioam6_id",
7254 		.data		= &ipv6_devconf.ioam6_id,
7255 		.maxlen		= sizeof(u32),
7256 		.mode		= 0644,
7257 		.proc_handler	= proc_douintvec_minmax,
7258 		.extra1		= (void *)SYSCTL_ZERO,
7259 		.extra2		= (void *)&ioam6_if_id_max,
7260 	},
7261 	{
7262 		.procname	= "ioam6_id_wide",
7263 		.data		= &ipv6_devconf.ioam6_id_wide,
7264 		.maxlen		= sizeof(u32),
7265 		.mode		= 0644,
7266 		.proc_handler	= proc_douintvec,
7267 	},
7268 	{
7269 		.procname	= "ndisc_evict_nocarrier",
7270 		.data		= &ipv6_devconf.ndisc_evict_nocarrier,
7271 		.maxlen		= sizeof(u8),
7272 		.mode		= 0644,
7273 		.proc_handler	= proc_dou8vec_minmax,
7274 		.extra1		= (void *)SYSCTL_ZERO,
7275 		.extra2		= (void *)SYSCTL_ONE,
7276 	},
7277 	{
7278 		.procname	= "accept_untracked_na",
7279 		.data		= &ipv6_devconf.accept_untracked_na,
7280 		.maxlen		= sizeof(int),
7281 		.mode		= 0644,
7282 		.proc_handler	= proc_dointvec_minmax,
7283 		.extra1		= SYSCTL_ZERO,
7284 		.extra2		= SYSCTL_TWO,
7285 	},
7286 	{
7287 		.procname	= "force_forwarding",
7288 		.data		= &ipv6_devconf.force_forwarding,
7289 		.maxlen		= sizeof(int),
7290 		.mode		= 0644,
7291 		.proc_handler	= addrconf_sysctl_force_forwarding,
7292 	},
7293 };
7294 
__addrconf_sysctl_register(struct net * net,char * dev_name,struct inet6_dev * idev,struct ipv6_devconf * p)7295 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
7296 		struct inet6_dev *idev, struct ipv6_devconf *p)
7297 {
7298 	size_t table_size = ARRAY_SIZE(addrconf_sysctl);
7299 	int i, ifindex;
7300 	struct ctl_table *table;
7301 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
7302 
7303 	table = kmemdup(addrconf_sysctl, sizeof(addrconf_sysctl), GFP_KERNEL_ACCOUNT);
7304 	if (!table)
7305 		goto out;
7306 
7307 	for (i = 0; i < table_size; i++) {
7308 		table[i].data += (char *)p - (char *)&ipv6_devconf;
7309 		/* If one of these is already set, then it is not safe to
7310 		 * overwrite either of them: this makes proc_dointvec_minmax
7311 		 * usable.
7312 		 */
7313 		if (!table[i].extra1 && !table[i].extra2) {
7314 			table[i].extra1 = idev; /* embedded; no ref */
7315 			table[i].extra2 = net;
7316 		}
7317 	}
7318 
7319 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
7320 
7321 	p->sysctl_header = register_net_sysctl_sz(net, path, table,
7322 						  table_size);
7323 	if (!p->sysctl_header)
7324 		goto free;
7325 
7326 	if (!strcmp(dev_name, "all"))
7327 		ifindex = NETCONFA_IFINDEX_ALL;
7328 	else if (!strcmp(dev_name, "default"))
7329 		ifindex = NETCONFA_IFINDEX_DEFAULT;
7330 	else
7331 		ifindex = idev->dev->ifindex;
7332 	inet6_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL,
7333 				     ifindex, p);
7334 	return 0;
7335 
7336 free:
7337 	kfree(table);
7338 out:
7339 	return -ENOBUFS;
7340 }
7341 
__addrconf_sysctl_unregister(struct net * net,struct ipv6_devconf * p,int ifindex)7342 static void __addrconf_sysctl_unregister(struct net *net,
7343 					 struct ipv6_devconf *p, int ifindex)
7344 {
7345 	const struct ctl_table *table;
7346 
7347 	if (!p->sysctl_header)
7348 		return;
7349 
7350 	table = p->sysctl_header->ctl_table_arg;
7351 	unregister_net_sysctl_table(p->sysctl_header);
7352 	p->sysctl_header = NULL;
7353 	kfree(table);
7354 
7355 	inet6_netconf_notify_devconf(net, RTM_DELNETCONF, 0, ifindex, NULL);
7356 }
7357 
addrconf_sysctl_register(struct inet6_dev * idev)7358 static int addrconf_sysctl_register(struct inet6_dev *idev)
7359 {
7360 	int err;
7361 
7362 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
7363 		return -EINVAL;
7364 
7365 	err = neigh_sysctl_register(idev->dev, idev->nd_parms,
7366 				    &ndisc_ifinfo_sysctl_change);
7367 	if (err)
7368 		return err;
7369 	err = __addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
7370 					 idev, &idev->cnf);
7371 	if (err)
7372 		neigh_sysctl_unregister(idev->nd_parms);
7373 
7374 	return err;
7375 }
7376 
addrconf_sysctl_unregister(struct inet6_dev * idev)7377 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
7378 {
7379 	__addrconf_sysctl_unregister(dev_net(idev->dev), &idev->cnf,
7380 				     idev->dev->ifindex);
7381 	neigh_sysctl_unregister(idev->nd_parms);
7382 }
7383 
7384 
7385 #endif
7386 
addrconf_init_net(struct net * net)7387 static int __net_init addrconf_init_net(struct net *net)
7388 {
7389 	int err = -ENOMEM;
7390 	struct ipv6_devconf *all, *dflt;
7391 
7392 	spin_lock_init(&net->ipv6.addrconf_hash_lock);
7393 	INIT_DEFERRABLE_WORK(&net->ipv6.addr_chk_work, addrconf_verify_work);
7394 	net->ipv6.inet6_addr_lst = kcalloc(IN6_ADDR_HSIZE,
7395 					   sizeof(struct hlist_head),
7396 					   GFP_KERNEL);
7397 	if (!net->ipv6.inet6_addr_lst)
7398 		goto err_alloc_addr;
7399 
7400 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
7401 	if (!all)
7402 		goto err_alloc_all;
7403 
7404 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
7405 	if (!dflt)
7406 		goto err_alloc_dflt;
7407 
7408 	if (!net_eq(net, &init_net)) {
7409 		switch (net_inherit_devconf()) {
7410 		case 1:  /* copy from init_net */
7411 			memcpy(all, init_net.ipv6.devconf_all,
7412 			       sizeof(ipv6_devconf));
7413 			memcpy(dflt, init_net.ipv6.devconf_dflt,
7414 			       sizeof(ipv6_devconf_dflt));
7415 			break;
7416 		case 3: /* copy from the current netns */
7417 			memcpy(all, current->nsproxy->net_ns->ipv6.devconf_all,
7418 			       sizeof(ipv6_devconf));
7419 			memcpy(dflt,
7420 			       current->nsproxy->net_ns->ipv6.devconf_dflt,
7421 			       sizeof(ipv6_devconf_dflt));
7422 			break;
7423 		case 0:
7424 		case 2:
7425 			/* use compiled values */
7426 			break;
7427 		}
7428 	}
7429 
7430 	/* these will be inherited by all namespaces */
7431 	dflt->autoconf = ipv6_defaults.autoconf;
7432 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
7433 
7434 	dflt->stable_secret.initialized = false;
7435 	all->stable_secret.initialized = false;
7436 
7437 	net->ipv6.devconf_all = all;
7438 	net->ipv6.devconf_dflt = dflt;
7439 
7440 #ifdef CONFIG_SYSCTL
7441 	err = __addrconf_sysctl_register(net, "all", NULL, all);
7442 	if (err < 0)
7443 		goto err_reg_all;
7444 
7445 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
7446 	if (err < 0)
7447 		goto err_reg_dflt;
7448 #endif
7449 	return 0;
7450 
7451 #ifdef CONFIG_SYSCTL
7452 err_reg_dflt:
7453 	__addrconf_sysctl_unregister(net, all, NETCONFA_IFINDEX_ALL);
7454 err_reg_all:
7455 	kfree(dflt);
7456 	net->ipv6.devconf_dflt = NULL;
7457 #endif
7458 err_alloc_dflt:
7459 	kfree(all);
7460 	net->ipv6.devconf_all = NULL;
7461 err_alloc_all:
7462 	kfree(net->ipv6.inet6_addr_lst);
7463 err_alloc_addr:
7464 	return err;
7465 }
7466 
addrconf_exit_net(struct net * net)7467 static void __net_exit addrconf_exit_net(struct net *net)
7468 {
7469 	int i;
7470 
7471 #ifdef CONFIG_SYSCTL
7472 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_dflt,
7473 				     NETCONFA_IFINDEX_DEFAULT);
7474 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_all,
7475 				     NETCONFA_IFINDEX_ALL);
7476 #endif
7477 	kfree(net->ipv6.devconf_dflt);
7478 	net->ipv6.devconf_dflt = NULL;
7479 	kfree(net->ipv6.devconf_all);
7480 	net->ipv6.devconf_all = NULL;
7481 
7482 	cancel_delayed_work_sync(&net->ipv6.addr_chk_work);
7483 	/*
7484 	 *	Check hash table, then free it.
7485 	 */
7486 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
7487 		WARN_ON_ONCE(!hlist_empty(&net->ipv6.inet6_addr_lst[i]));
7488 
7489 	kfree(net->ipv6.inet6_addr_lst);
7490 	net->ipv6.inet6_addr_lst = NULL;
7491 }
7492 
7493 static struct pernet_operations addrconf_ops = {
7494 	.init = addrconf_init_net,
7495 	.exit = addrconf_exit_net,
7496 };
7497 
7498 static struct rtnl_af_ops inet6_ops __read_mostly = {
7499 	.family		  = AF_INET6,
7500 	.fill_link_af	  = inet6_fill_link_af,
7501 	.get_link_af_size = inet6_get_link_af_size,
7502 	.validate_link_af = inet6_validate_link_af,
7503 	.set_link_af	  = inet6_set_link_af,
7504 };
7505 
7506 static const struct rtnl_msg_handler addrconf_rtnl_msg_handlers[] __initconst_or_module = {
7507 	{.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_GETLINK,
7508 	 .dumpit = inet6_dump_ifinfo, .flags = RTNL_FLAG_DUMP_UNLOCKED},
7509 	{.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_NEWADDR,
7510 	 .doit = inet6_rtm_newaddr, .flags = RTNL_FLAG_DOIT_PERNET},
7511 	{.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_DELADDR,
7512 	 .doit = inet6_rtm_deladdr, .flags = RTNL_FLAG_DOIT_PERNET},
7513 	{.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_GETADDR,
7514 	 .doit = inet6_rtm_getaddr, .dumpit = inet6_dump_ifaddr,
7515 	 .flags = RTNL_FLAG_DOIT_UNLOCKED | RTNL_FLAG_DUMP_UNLOCKED},
7516 	{.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_GETMULTICAST,
7517 	 .dumpit = inet6_dump_ifmcaddr,
7518 	 .flags = RTNL_FLAG_DUMP_UNLOCKED},
7519 	{.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_GETANYCAST,
7520 	 .dumpit = inet6_dump_ifacaddr,
7521 	 .flags = RTNL_FLAG_DUMP_UNLOCKED},
7522 	{.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_GETNETCONF,
7523 	 .doit = inet6_netconf_get_devconf, .dumpit = inet6_netconf_dump_devconf,
7524 	 .flags = RTNL_FLAG_DOIT_UNLOCKED | RTNL_FLAG_DUMP_UNLOCKED},
7525 };
7526 
7527 /*
7528  *	Init / cleanup code
7529  */
7530 
addrconf_init(void)7531 int __init addrconf_init(void)
7532 {
7533 	struct inet6_dev *idev;
7534 	int err;
7535 
7536 	err = ipv6_addr_label_init();
7537 	if (err < 0) {
7538 		pr_crit("%s: cannot initialize default policy table: %d\n",
7539 			__func__, err);
7540 		goto out;
7541 	}
7542 
7543 	err = register_pernet_subsys(&addrconf_ops);
7544 	if (err < 0)
7545 		goto out_addrlabel;
7546 
7547 	/* All works using addrconf_wq need to lock rtnl. */
7548 	addrconf_wq = create_singlethread_workqueue("ipv6_addrconf");
7549 	if (!addrconf_wq) {
7550 		err = -ENOMEM;
7551 		goto out_nowq;
7552 	}
7553 
7554 	rtnl_net_lock(&init_net);
7555 	idev = ipv6_add_dev(blackhole_netdev);
7556 	rtnl_net_unlock(&init_net);
7557 	if (IS_ERR(idev)) {
7558 		err = PTR_ERR(idev);
7559 		goto errlo;
7560 	}
7561 
7562 	ip6_route_init_special_entries();
7563 
7564 	register_netdevice_notifier(&ipv6_dev_notf);
7565 
7566 	addrconf_verify(&init_net);
7567 
7568 	err = rtnl_af_register(&inet6_ops);
7569 	if (err)
7570 		goto erraf;
7571 
7572 	err = rtnl_register_many(addrconf_rtnl_msg_handlers);
7573 	if (err)
7574 		goto errout;
7575 
7576 	err = ipv6_addr_label_rtnl_register();
7577 	if (err < 0)
7578 		goto errout;
7579 
7580 	return 0;
7581 errout:
7582 	rtnl_unregister_all(PF_INET6);
7583 	rtnl_af_unregister(&inet6_ops);
7584 erraf:
7585 	unregister_netdevice_notifier(&ipv6_dev_notf);
7586 errlo:
7587 	destroy_workqueue(addrconf_wq);
7588 out_nowq:
7589 	unregister_pernet_subsys(&addrconf_ops);
7590 out_addrlabel:
7591 	ipv6_addr_label_cleanup();
7592 out:
7593 	return err;
7594 }
7595 
addrconf_cleanup(void)7596 void addrconf_cleanup(void)
7597 {
7598 	struct net_device *dev;
7599 
7600 	unregister_netdevice_notifier(&ipv6_dev_notf);
7601 	unregister_pernet_subsys(&addrconf_ops);
7602 	ipv6_addr_label_cleanup();
7603 
7604 	rtnl_af_unregister(&inet6_ops);
7605 
7606 	rtnl_net_lock(&init_net);
7607 
7608 	/* clean dev list */
7609 	for_each_netdev(&init_net, dev) {
7610 		if (!__in6_dev_get_rtnl_net(dev))
7611 			continue;
7612 		addrconf_ifdown(dev, true);
7613 	}
7614 	addrconf_ifdown(init_net.loopback_dev, true);
7615 
7616 	rtnl_net_unlock(&init_net);
7617 
7618 	destroy_workqueue(addrconf_wq);
7619 }
7620