xref: /linux/net/ipv6/addrconf.c (revision 4003c9e78778e93188a09d6043a74f7154449d43)
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 <linux/if_tunnel.h>
84 #include <linux/rtnetlink.h>
85 #include <linux/netconf.h>
86 #include <linux/random.h>
87 #include <linux/uaccess.h>
88 #include <linux/unaligned.h>
89 
90 #include <linux/proc_fs.h>
91 #include <linux/seq_file.h>
92 #include <linux/export.h>
93 #include <linux/ioam6.h>
94 
95 #define IPV6_MAX_STRLEN \
96 	sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")
97 
cstamp_delta(unsigned long cstamp)98 static inline u32 cstamp_delta(unsigned long cstamp)
99 {
100 	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
101 }
102 
rfc3315_s14_backoff_init(s32 irt)103 static inline s32 rfc3315_s14_backoff_init(s32 irt)
104 {
105 	/* multiply 'initial retransmission time' by 0.9 .. 1.1 */
106 	u64 tmp = get_random_u32_inclusive(900000, 1100000) * (u64)irt;
107 	do_div(tmp, 1000000);
108 	return (s32)tmp;
109 }
110 
rfc3315_s14_backoff_update(s32 rt,s32 mrt)111 static inline s32 rfc3315_s14_backoff_update(s32 rt, s32 mrt)
112 {
113 	/* multiply 'retransmission timeout' by 1.9 .. 2.1 */
114 	u64 tmp = get_random_u32_inclusive(1900000, 2100000) * (u64)rt;
115 	do_div(tmp, 1000000);
116 	if ((s32)tmp > mrt) {
117 		/* multiply 'maximum retransmission time' by 0.9 .. 1.1 */
118 		tmp = get_random_u32_inclusive(900000, 1100000) * (u64)mrt;
119 		do_div(tmp, 1000000);
120 	}
121 	return (s32)tmp;
122 }
123 
124 #ifdef CONFIG_SYSCTL
125 static int addrconf_sysctl_register(struct inet6_dev *idev);
126 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
127 #else
addrconf_sysctl_register(struct inet6_dev * idev)128 static inline int addrconf_sysctl_register(struct inet6_dev *idev)
129 {
130 	return 0;
131 }
132 
addrconf_sysctl_unregister(struct inet6_dev * idev)133 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
134 {
135 }
136 #endif
137 
138 static void ipv6_gen_rnd_iid(struct in6_addr *addr);
139 
140 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
141 static int ipv6_count_addresses(const struct inet6_dev *idev);
142 static int ipv6_generate_stable_address(struct in6_addr *addr,
143 					u8 dad_count,
144 					const struct inet6_dev *idev);
145 
146 #define IN6_ADDR_HSIZE_SHIFT	8
147 #define IN6_ADDR_HSIZE		(1 << IN6_ADDR_HSIZE_SHIFT)
148 
149 static void addrconf_verify(struct net *net);
150 static void addrconf_verify_rtnl(struct net *net);
151 
152 static struct workqueue_struct *addrconf_wq;
153 
154 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
155 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
156 
157 static void addrconf_type_change(struct net_device *dev,
158 				 unsigned long event);
159 static int addrconf_ifdown(struct net_device *dev, bool unregister);
160 
161 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
162 						  int plen,
163 						  const struct net_device *dev,
164 						  u32 flags, u32 noflags,
165 						  bool no_gw);
166 
167 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
168 static void addrconf_dad_work(struct work_struct *w);
169 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
170 				   bool send_na);
171 static void addrconf_dad_run(struct inet6_dev *idev, bool restart);
172 static void addrconf_rs_timer(struct timer_list *t);
173 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
174 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
175 
176 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
177 				struct prefix_info *pinfo);
178 
179 static struct ipv6_devconf ipv6_devconf __read_mostly = {
180 	.forwarding		= 0,
181 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
182 	.mtu6			= IPV6_MIN_MTU,
183 	.accept_ra		= 1,
184 	.accept_redirects	= 1,
185 	.autoconf		= 1,
186 	.force_mld_version	= 0,
187 	.mldv1_unsolicited_report_interval = 10 * HZ,
188 	.mldv2_unsolicited_report_interval = HZ,
189 	.dad_transmits		= 1,
190 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
191 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
192 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
193 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
194 	.use_tempaddr		= 0,
195 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
196 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
197 	.regen_min_advance	= REGEN_MIN_ADVANCE,
198 	.regen_max_retry	= REGEN_MAX_RETRY,
199 	.max_desync_factor	= MAX_DESYNC_FACTOR,
200 	.max_addresses		= IPV6_MAX_ADDRESSES,
201 	.accept_ra_defrtr	= 1,
202 	.ra_defrtr_metric	= IP6_RT_PRIO_USER,
203 	.accept_ra_from_local	= 0,
204 	.accept_ra_min_hop_limit= 1,
205 	.accept_ra_min_lft	= 0,
206 	.accept_ra_pinfo	= 1,
207 #ifdef CONFIG_IPV6_ROUTER_PREF
208 	.accept_ra_rtr_pref	= 1,
209 	.rtr_probe_interval	= 60 * HZ,
210 #ifdef CONFIG_IPV6_ROUTE_INFO
211 	.accept_ra_rt_info_min_plen = 0,
212 	.accept_ra_rt_info_max_plen = 0,
213 #endif
214 #endif
215 	.proxy_ndp		= 0,
216 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
217 	.disable_ipv6		= 0,
218 	.accept_dad		= 0,
219 	.suppress_frag_ndisc	= 1,
220 	.accept_ra_mtu		= 1,
221 	.stable_secret		= {
222 		.initialized = false,
223 	},
224 	.use_oif_addrs_only	= 0,
225 	.ignore_routes_with_linkdown = 0,
226 	.keep_addr_on_down	= 0,
227 	.seg6_enabled		= 0,
228 #ifdef CONFIG_IPV6_SEG6_HMAC
229 	.seg6_require_hmac	= 0,
230 #endif
231 	.enhanced_dad           = 1,
232 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
233 	.disable_policy		= 0,
234 	.rpl_seg_enabled	= 0,
235 	.ioam6_enabled		= 0,
236 	.ioam6_id               = IOAM6_DEFAULT_IF_ID,
237 	.ioam6_id_wide		= IOAM6_DEFAULT_IF_ID_WIDE,
238 	.ndisc_evict_nocarrier	= 1,
239 	.ra_honor_pio_life	= 0,
240 	.ra_honor_pio_pflag	= 0,
241 };
242 
243 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
244 	.forwarding		= 0,
245 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
246 	.mtu6			= IPV6_MIN_MTU,
247 	.accept_ra		= 1,
248 	.accept_redirects	= 1,
249 	.autoconf		= 1,
250 	.force_mld_version	= 0,
251 	.mldv1_unsolicited_report_interval = 10 * HZ,
252 	.mldv2_unsolicited_report_interval = HZ,
253 	.dad_transmits		= 1,
254 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
255 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
256 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
257 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
258 	.use_tempaddr		= 0,
259 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
260 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
261 	.regen_min_advance	= REGEN_MIN_ADVANCE,
262 	.regen_max_retry	= REGEN_MAX_RETRY,
263 	.max_desync_factor	= MAX_DESYNC_FACTOR,
264 	.max_addresses		= IPV6_MAX_ADDRESSES,
265 	.accept_ra_defrtr	= 1,
266 	.ra_defrtr_metric	= IP6_RT_PRIO_USER,
267 	.accept_ra_from_local	= 0,
268 	.accept_ra_min_hop_limit= 1,
269 	.accept_ra_min_lft	= 0,
270 	.accept_ra_pinfo	= 1,
271 #ifdef CONFIG_IPV6_ROUTER_PREF
272 	.accept_ra_rtr_pref	= 1,
273 	.rtr_probe_interval	= 60 * HZ,
274 #ifdef CONFIG_IPV6_ROUTE_INFO
275 	.accept_ra_rt_info_min_plen = 0,
276 	.accept_ra_rt_info_max_plen = 0,
277 #endif
278 #endif
279 	.proxy_ndp		= 0,
280 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
281 	.disable_ipv6		= 0,
282 	.accept_dad		= 1,
283 	.suppress_frag_ndisc	= 1,
284 	.accept_ra_mtu		= 1,
285 	.stable_secret		= {
286 		.initialized = false,
287 	},
288 	.use_oif_addrs_only	= 0,
289 	.ignore_routes_with_linkdown = 0,
290 	.keep_addr_on_down	= 0,
291 	.seg6_enabled		= 0,
292 #ifdef CONFIG_IPV6_SEG6_HMAC
293 	.seg6_require_hmac	= 0,
294 #endif
295 	.enhanced_dad           = 1,
296 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
297 	.disable_policy		= 0,
298 	.rpl_seg_enabled	= 0,
299 	.ioam6_enabled		= 0,
300 	.ioam6_id               = IOAM6_DEFAULT_IF_ID,
301 	.ioam6_id_wide		= IOAM6_DEFAULT_IF_ID_WIDE,
302 	.ndisc_evict_nocarrier	= 1,
303 	.ra_honor_pio_life	= 0,
304 	.ra_honor_pio_pflag	= 0,
305 };
306 
307 /* Check if link is ready: is it up and is a valid qdisc available */
addrconf_link_ready(const struct net_device * dev)308 static inline bool addrconf_link_ready(const struct net_device *dev)
309 {
310 	return netif_oper_up(dev) && !qdisc_tx_is_noop(dev);
311 }
312 
addrconf_del_rs_timer(struct inet6_dev * idev)313 static void addrconf_del_rs_timer(struct inet6_dev *idev)
314 {
315 	if (del_timer(&idev->rs_timer))
316 		__in6_dev_put(idev);
317 }
318 
addrconf_del_dad_work(struct inet6_ifaddr * ifp)319 static void addrconf_del_dad_work(struct inet6_ifaddr *ifp)
320 {
321 	if (cancel_delayed_work(&ifp->dad_work))
322 		__in6_ifa_put(ifp);
323 }
324 
addrconf_mod_rs_timer(struct inet6_dev * idev,unsigned long when)325 static void addrconf_mod_rs_timer(struct inet6_dev *idev,
326 				  unsigned long when)
327 {
328 	if (!mod_timer(&idev->rs_timer, jiffies + when))
329 		in6_dev_hold(idev);
330 }
331 
addrconf_mod_dad_work(struct inet6_ifaddr * ifp,unsigned long delay)332 static void addrconf_mod_dad_work(struct inet6_ifaddr *ifp,
333 				   unsigned long delay)
334 {
335 	in6_ifa_hold(ifp);
336 	if (mod_delayed_work(addrconf_wq, &ifp->dad_work, delay))
337 		in6_ifa_put(ifp);
338 }
339 
snmp6_alloc_dev(struct inet6_dev * idev)340 static int snmp6_alloc_dev(struct inet6_dev *idev)
341 {
342 	int i;
343 
344 	idev->stats.ipv6 = alloc_percpu_gfp(struct ipstats_mib, GFP_KERNEL_ACCOUNT);
345 	if (!idev->stats.ipv6)
346 		goto err_ip;
347 
348 	for_each_possible_cpu(i) {
349 		struct ipstats_mib *addrconf_stats;
350 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6, i);
351 		u64_stats_init(&addrconf_stats->syncp);
352 	}
353 
354 
355 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
356 					GFP_KERNEL);
357 	if (!idev->stats.icmpv6dev)
358 		goto err_icmp;
359 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
360 					   GFP_KERNEL_ACCOUNT);
361 	if (!idev->stats.icmpv6msgdev)
362 		goto err_icmpmsg;
363 
364 	return 0;
365 
366 err_icmpmsg:
367 	kfree(idev->stats.icmpv6dev);
368 err_icmp:
369 	free_percpu(idev->stats.ipv6);
370 err_ip:
371 	return -ENOMEM;
372 }
373 
ipv6_add_dev(struct net_device * dev)374 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
375 {
376 	struct inet6_dev *ndev;
377 	int err = -ENOMEM;
378 
379 	ASSERT_RTNL();
380 
381 	if (dev->mtu < IPV6_MIN_MTU && dev != blackhole_netdev)
382 		return ERR_PTR(-EINVAL);
383 
384 	ndev = kzalloc(sizeof(*ndev), GFP_KERNEL_ACCOUNT);
385 	if (!ndev)
386 		return ERR_PTR(err);
387 
388 	rwlock_init(&ndev->lock);
389 	ndev->dev = dev;
390 	INIT_LIST_HEAD(&ndev->addr_list);
391 	timer_setup(&ndev->rs_timer, addrconf_rs_timer, 0);
392 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
393 
394 	if (ndev->cnf.stable_secret.initialized)
395 		ndev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
396 
397 	ndev->cnf.mtu6 = dev->mtu;
398 	ndev->ra_mtu = 0;
399 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
400 	if (!ndev->nd_parms) {
401 		kfree(ndev);
402 		return ERR_PTR(err);
403 	}
404 	if (ndev->cnf.forwarding)
405 		dev_disable_lro(dev);
406 	/* We refer to the device */
407 	netdev_hold(dev, &ndev->dev_tracker, GFP_KERNEL);
408 
409 	if (snmp6_alloc_dev(ndev) < 0) {
410 		netdev_dbg(dev, "%s: cannot allocate memory for statistics\n",
411 			   __func__);
412 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
413 		netdev_put(dev, &ndev->dev_tracker);
414 		kfree(ndev);
415 		return ERR_PTR(err);
416 	}
417 
418 	if (dev != blackhole_netdev) {
419 		if (snmp6_register_dev(ndev) < 0) {
420 			netdev_dbg(dev, "%s: cannot create /proc/net/dev_snmp6/%s\n",
421 				   __func__, dev->name);
422 			goto err_release;
423 		}
424 	}
425 	/* One reference from device. */
426 	refcount_set(&ndev->refcnt, 1);
427 
428 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
429 		ndev->cnf.accept_dad = -1;
430 
431 #if IS_ENABLED(CONFIG_IPV6_SIT)
432 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
433 		pr_info("%s: Disabled Multicast RS\n", dev->name);
434 		ndev->cnf.rtr_solicits = 0;
435 	}
436 #endif
437 
438 	INIT_LIST_HEAD(&ndev->tempaddr_list);
439 	ndev->desync_factor = U32_MAX;
440 	if ((dev->flags&IFF_LOOPBACK) ||
441 	    dev->type == ARPHRD_TUNNEL ||
442 	    dev->type == ARPHRD_TUNNEL6 ||
443 	    dev->type == ARPHRD_SIT ||
444 	    dev->type == ARPHRD_NONE) {
445 		ndev->cnf.use_tempaddr = -1;
446 	}
447 
448 	ndev->token = in6addr_any;
449 
450 	if (netif_running(dev) && addrconf_link_ready(dev))
451 		ndev->if_flags |= IF_READY;
452 
453 	ipv6_mc_init_dev(ndev);
454 	ndev->tstamp = jiffies;
455 	if (dev != blackhole_netdev) {
456 		err = addrconf_sysctl_register(ndev);
457 		if (err) {
458 			ipv6_mc_destroy_dev(ndev);
459 			snmp6_unregister_dev(ndev);
460 			goto err_release;
461 		}
462 	}
463 	/* protected by rtnl_lock */
464 	rcu_assign_pointer(dev->ip6_ptr, ndev);
465 
466 	if (dev != blackhole_netdev) {
467 		/* Join interface-local all-node multicast group */
468 		ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
469 
470 		/* Join all-node multicast group */
471 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
472 
473 		/* Join all-router multicast group if forwarding is set */
474 		if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
475 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
476 	}
477 	return ndev;
478 
479 err_release:
480 	neigh_parms_release(&nd_tbl, ndev->nd_parms);
481 	ndev->dead = 1;
482 	in6_dev_finish_destroy(ndev);
483 	return ERR_PTR(err);
484 }
485 
ipv6_find_idev(struct net_device * dev)486 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
487 {
488 	struct inet6_dev *idev;
489 
490 	ASSERT_RTNL();
491 
492 	idev = __in6_dev_get(dev);
493 	if (!idev) {
494 		idev = ipv6_add_dev(dev);
495 		if (IS_ERR(idev))
496 			return idev;
497 	}
498 
499 	if (dev->flags&IFF_UP)
500 		ipv6_mc_up(idev);
501 	return idev;
502 }
503 
inet6_netconf_msgsize_devconf(int type)504 static int inet6_netconf_msgsize_devconf(int type)
505 {
506 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
507 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
508 	bool all = false;
509 
510 	if (type == NETCONFA_ALL)
511 		all = true;
512 
513 	if (all || type == NETCONFA_FORWARDING)
514 		size += nla_total_size(4);
515 #ifdef CONFIG_IPV6_MROUTE
516 	if (all || type == NETCONFA_MC_FORWARDING)
517 		size += nla_total_size(4);
518 #endif
519 	if (all || type == NETCONFA_PROXY_NEIGH)
520 		size += nla_total_size(4);
521 
522 	if (all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN)
523 		size += nla_total_size(4);
524 
525 	return size;
526 }
527 
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)528 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
529 				      struct ipv6_devconf *devconf, u32 portid,
530 				      u32 seq, int event, unsigned int flags,
531 				      int type)
532 {
533 	struct nlmsghdr  *nlh;
534 	struct netconfmsg *ncm;
535 	bool all = false;
536 
537 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
538 			flags);
539 	if (!nlh)
540 		return -EMSGSIZE;
541 
542 	if (type == NETCONFA_ALL)
543 		all = true;
544 
545 	ncm = nlmsg_data(nlh);
546 	ncm->ncm_family = AF_INET6;
547 
548 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
549 		goto nla_put_failure;
550 
551 	if (!devconf)
552 		goto out;
553 
554 	if ((all || type == NETCONFA_FORWARDING) &&
555 	    nla_put_s32(skb, NETCONFA_FORWARDING,
556 			READ_ONCE(devconf->forwarding)) < 0)
557 		goto nla_put_failure;
558 #ifdef CONFIG_IPV6_MROUTE
559 	if ((all || type == NETCONFA_MC_FORWARDING) &&
560 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
561 			atomic_read(&devconf->mc_forwarding)) < 0)
562 		goto nla_put_failure;
563 #endif
564 	if ((all || type == NETCONFA_PROXY_NEIGH) &&
565 	    nla_put_s32(skb, NETCONFA_PROXY_NEIGH,
566 			READ_ONCE(devconf->proxy_ndp)) < 0)
567 		goto nla_put_failure;
568 
569 	if ((all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) &&
570 	    nla_put_s32(skb, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
571 			READ_ONCE(devconf->ignore_routes_with_linkdown)) < 0)
572 		goto nla_put_failure;
573 
574 out:
575 	nlmsg_end(skb, nlh);
576 	return 0;
577 
578 nla_put_failure:
579 	nlmsg_cancel(skb, nlh);
580 	return -EMSGSIZE;
581 }
582 
inet6_netconf_notify_devconf(struct net * net,int event,int type,int ifindex,struct ipv6_devconf * devconf)583 void inet6_netconf_notify_devconf(struct net *net, int event, int type,
584 				  int ifindex, struct ipv6_devconf *devconf)
585 {
586 	struct sk_buff *skb;
587 	int err = -ENOBUFS;
588 
589 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_KERNEL);
590 	if (!skb)
591 		goto errout;
592 
593 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
594 					 event, 0, type);
595 	if (err < 0) {
596 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
597 		WARN_ON(err == -EMSGSIZE);
598 		kfree_skb(skb);
599 		goto errout;
600 	}
601 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_KERNEL);
602 	return;
603 errout:
604 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
605 }
606 
607 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
608 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
609 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
610 	[NETCONFA_PROXY_NEIGH]	= { .len = sizeof(int) },
611 	[NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN]	= { .len = sizeof(int) },
612 };
613 
inet6_netconf_valid_get_req(struct sk_buff * skb,const struct nlmsghdr * nlh,struct nlattr ** tb,struct netlink_ext_ack * extack)614 static int inet6_netconf_valid_get_req(struct sk_buff *skb,
615 				       const struct nlmsghdr *nlh,
616 				       struct nlattr **tb,
617 				       struct netlink_ext_ack *extack)
618 {
619 	int i, err;
620 
621 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(struct netconfmsg))) {
622 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf get request");
623 		return -EINVAL;
624 	}
625 
626 	if (!netlink_strict_get_check(skb))
627 		return nlmsg_parse_deprecated(nlh, sizeof(struct netconfmsg),
628 					      tb, NETCONFA_MAX,
629 					      devconf_ipv6_policy, extack);
630 
631 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct netconfmsg),
632 					    tb, NETCONFA_MAX,
633 					    devconf_ipv6_policy, extack);
634 	if (err)
635 		return err;
636 
637 	for (i = 0; i <= NETCONFA_MAX; i++) {
638 		if (!tb[i])
639 			continue;
640 
641 		switch (i) {
642 		case NETCONFA_IFINDEX:
643 			break;
644 		default:
645 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in netconf get request");
646 			return -EINVAL;
647 		}
648 	}
649 
650 	return 0;
651 }
652 
inet6_netconf_get_devconf(struct sk_buff * in_skb,struct nlmsghdr * nlh,struct netlink_ext_ack * extack)653 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
654 				     struct nlmsghdr *nlh,
655 				     struct netlink_ext_ack *extack)
656 {
657 	struct net *net = sock_net(in_skb->sk);
658 	struct nlattr *tb[NETCONFA_MAX+1];
659 	struct inet6_dev *in6_dev = NULL;
660 	struct net_device *dev = NULL;
661 	struct sk_buff *skb;
662 	struct ipv6_devconf *devconf;
663 	int ifindex;
664 	int err;
665 
666 	err = inet6_netconf_valid_get_req(in_skb, nlh, tb, extack);
667 	if (err < 0)
668 		return err;
669 
670 	if (!tb[NETCONFA_IFINDEX])
671 		return -EINVAL;
672 
673 	err = -EINVAL;
674 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
675 	switch (ifindex) {
676 	case NETCONFA_IFINDEX_ALL:
677 		devconf = net->ipv6.devconf_all;
678 		break;
679 	case NETCONFA_IFINDEX_DEFAULT:
680 		devconf = net->ipv6.devconf_dflt;
681 		break;
682 	default:
683 		dev = dev_get_by_index(net, ifindex);
684 		if (!dev)
685 			return -EINVAL;
686 		in6_dev = in6_dev_get(dev);
687 		if (!in6_dev)
688 			goto errout;
689 		devconf = &in6_dev->cnf;
690 		break;
691 	}
692 
693 	err = -ENOBUFS;
694 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL);
695 	if (!skb)
696 		goto errout;
697 
698 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
699 					 NETLINK_CB(in_skb).portid,
700 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
701 					 NETCONFA_ALL);
702 	if (err < 0) {
703 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
704 		WARN_ON(err == -EMSGSIZE);
705 		kfree_skb(skb);
706 		goto errout;
707 	}
708 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
709 errout:
710 	if (in6_dev)
711 		in6_dev_put(in6_dev);
712 	dev_put(dev);
713 	return err;
714 }
715 
716 /* Combine dev_addr_genid and dev_base_seq to detect changes.
717  */
inet6_base_seq(const struct net * net)718 static u32 inet6_base_seq(const struct net *net)
719 {
720 	u32 res = atomic_read(&net->ipv6.dev_addr_genid) +
721 		  READ_ONCE(net->dev_base_seq);
722 
723 	/* Must not return 0 (see nl_dump_check_consistent()).
724 	 * Chose a value far away from 0.
725 	 */
726 	if (!res)
727 		res = 0x80000000;
728 	return res;
729 }
730 
inet6_netconf_dump_devconf(struct sk_buff * skb,struct netlink_callback * cb)731 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
732 				      struct netlink_callback *cb)
733 {
734 	const struct nlmsghdr *nlh = cb->nlh;
735 	struct net *net = sock_net(skb->sk);
736 	struct {
737 		unsigned long ifindex;
738 		unsigned int all_default;
739 	} *ctx = (void *)cb->ctx;
740 	struct net_device *dev;
741 	struct inet6_dev *idev;
742 	int err = 0;
743 
744 	if (cb->strict_check) {
745 		struct netlink_ext_ack *extack = cb->extack;
746 		struct netconfmsg *ncm;
747 
748 		if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ncm))) {
749 			NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf dump request");
750 			return -EINVAL;
751 		}
752 
753 		if (nlmsg_attrlen(nlh, sizeof(*ncm))) {
754 			NL_SET_ERR_MSG_MOD(extack, "Invalid data after header in netconf dump request");
755 			return -EINVAL;
756 		}
757 	}
758 
759 	rcu_read_lock();
760 	for_each_netdev_dump(net, dev, ctx->ifindex) {
761 		idev = __in6_dev_get(dev);
762 		if (!idev)
763 			continue;
764 		err = inet6_netconf_fill_devconf(skb, dev->ifindex,
765 					         &idev->cnf,
766 						 NETLINK_CB(cb->skb).portid,
767 						 nlh->nlmsg_seq,
768 						 RTM_NEWNETCONF,
769 						 NLM_F_MULTI,
770 						 NETCONFA_ALL);
771 		if (err < 0)
772 			goto done;
773 	}
774 	if (ctx->all_default == 0) {
775 		err = inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
776 						 net->ipv6.devconf_all,
777 						 NETLINK_CB(cb->skb).portid,
778 						 nlh->nlmsg_seq,
779 						 RTM_NEWNETCONF, NLM_F_MULTI,
780 						 NETCONFA_ALL);
781 		if (err < 0)
782 			goto done;
783 		ctx->all_default++;
784 	}
785 	if (ctx->all_default == 1) {
786 		err = inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
787 						 net->ipv6.devconf_dflt,
788 						 NETLINK_CB(cb->skb).portid,
789 						 nlh->nlmsg_seq,
790 						 RTM_NEWNETCONF, NLM_F_MULTI,
791 						 NETCONFA_ALL);
792 		if (err < 0)
793 			goto done;
794 		ctx->all_default++;
795 	}
796 done:
797 	rcu_read_unlock();
798 	return err;
799 }
800 
801 #ifdef CONFIG_SYSCTL
dev_forward_change(struct inet6_dev * idev)802 static void dev_forward_change(struct inet6_dev *idev)
803 {
804 	struct net_device *dev;
805 	struct inet6_ifaddr *ifa;
806 	LIST_HEAD(tmp_addr_list);
807 
808 	if (!idev)
809 		return;
810 	dev = idev->dev;
811 	if (idev->cnf.forwarding)
812 		dev_disable_lro(dev);
813 	if (dev->flags & IFF_MULTICAST) {
814 		if (idev->cnf.forwarding) {
815 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
816 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
817 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
818 		} else {
819 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
820 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
821 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
822 		}
823 	}
824 
825 	read_lock_bh(&idev->lock);
826 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
827 		if (ifa->flags&IFA_F_TENTATIVE)
828 			continue;
829 		list_add_tail(&ifa->if_list_aux, &tmp_addr_list);
830 	}
831 	read_unlock_bh(&idev->lock);
832 
833 	while (!list_empty(&tmp_addr_list)) {
834 		ifa = list_first_entry(&tmp_addr_list,
835 				       struct inet6_ifaddr, if_list_aux);
836 		list_del(&ifa->if_list_aux);
837 		if (idev->cnf.forwarding)
838 			addrconf_join_anycast(ifa);
839 		else
840 			addrconf_leave_anycast(ifa);
841 	}
842 
843 	inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
844 				     NETCONFA_FORWARDING,
845 				     dev->ifindex, &idev->cnf);
846 }
847 
848 
addrconf_forward_change(struct net * net,__s32 newf)849 static void addrconf_forward_change(struct net *net, __s32 newf)
850 {
851 	struct net_device *dev;
852 	struct inet6_dev *idev;
853 
854 	for_each_netdev(net, dev) {
855 		idev = __in6_dev_get_rtnl_net(dev);
856 		if (idev) {
857 			int changed = (!idev->cnf.forwarding) ^ (!newf);
858 
859 			WRITE_ONCE(idev->cnf.forwarding, newf);
860 			if (changed)
861 				dev_forward_change(idev);
862 		}
863 	}
864 }
865 
addrconf_fixup_forwarding(const struct ctl_table * table,int * p,int newf)866 static int addrconf_fixup_forwarding(const struct ctl_table *table, int *p, int newf)
867 {
868 	struct net *net = (struct net *)table->extra2;
869 	int old;
870 
871 	if (!rtnl_net_trylock(net))
872 		return restart_syscall();
873 
874 	old = *p;
875 	WRITE_ONCE(*p, newf);
876 
877 	if (p == &net->ipv6.devconf_dflt->forwarding) {
878 		if ((!newf) ^ (!old))
879 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
880 						     NETCONFA_FORWARDING,
881 						     NETCONFA_IFINDEX_DEFAULT,
882 						     net->ipv6.devconf_dflt);
883 		rtnl_net_unlock(net);
884 		return 0;
885 	}
886 
887 	if (p == &net->ipv6.devconf_all->forwarding) {
888 		int old_dflt = net->ipv6.devconf_dflt->forwarding;
889 
890 		WRITE_ONCE(net->ipv6.devconf_dflt->forwarding, newf);
891 		if ((!newf) ^ (!old_dflt))
892 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
893 						     NETCONFA_FORWARDING,
894 						     NETCONFA_IFINDEX_DEFAULT,
895 						     net->ipv6.devconf_dflt);
896 
897 		addrconf_forward_change(net, newf);
898 		if ((!newf) ^ (!old))
899 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
900 						     NETCONFA_FORWARDING,
901 						     NETCONFA_IFINDEX_ALL,
902 						     net->ipv6.devconf_all);
903 	} else if ((!newf) ^ (!old))
904 		dev_forward_change((struct inet6_dev *)table->extra1);
905 	rtnl_net_unlock(net);
906 
907 	if (newf)
908 		rt6_purge_dflt_routers(net);
909 	return 1;
910 }
911 
addrconf_linkdown_change(struct net * net,__s32 newf)912 static void addrconf_linkdown_change(struct net *net, __s32 newf)
913 {
914 	struct net_device *dev;
915 	struct inet6_dev *idev;
916 
917 	for_each_netdev(net, dev) {
918 		idev = __in6_dev_get_rtnl_net(dev);
919 		if (idev) {
920 			int changed = (!idev->cnf.ignore_routes_with_linkdown) ^ (!newf);
921 
922 			WRITE_ONCE(idev->cnf.ignore_routes_with_linkdown, newf);
923 			if (changed)
924 				inet6_netconf_notify_devconf(dev_net(dev),
925 							     RTM_NEWNETCONF,
926 							     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
927 							     dev->ifindex,
928 							     &idev->cnf);
929 		}
930 	}
931 }
932 
addrconf_fixup_linkdown(const struct ctl_table * table,int * p,int newf)933 static int addrconf_fixup_linkdown(const struct ctl_table *table, int *p, int newf)
934 {
935 	struct net *net = (struct net *)table->extra2;
936 	int old;
937 
938 	if (!rtnl_net_trylock(net))
939 		return restart_syscall();
940 
941 	old = *p;
942 	WRITE_ONCE(*p, newf);
943 
944 	if (p == &net->ipv6.devconf_dflt->ignore_routes_with_linkdown) {
945 		if ((!newf) ^ (!old))
946 			inet6_netconf_notify_devconf(net,
947 						     RTM_NEWNETCONF,
948 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
949 						     NETCONFA_IFINDEX_DEFAULT,
950 						     net->ipv6.devconf_dflt);
951 		rtnl_net_unlock(net);
952 		return 0;
953 	}
954 
955 	if (p == &net->ipv6.devconf_all->ignore_routes_with_linkdown) {
956 		WRITE_ONCE(net->ipv6.devconf_dflt->ignore_routes_with_linkdown, newf);
957 		addrconf_linkdown_change(net, newf);
958 		if ((!newf) ^ (!old))
959 			inet6_netconf_notify_devconf(net,
960 						     RTM_NEWNETCONF,
961 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
962 						     NETCONFA_IFINDEX_ALL,
963 						     net->ipv6.devconf_all);
964 	}
965 
966 	rtnl_net_unlock(net);
967 
968 	return 1;
969 }
970 
971 #endif
972 
973 /* Nobody refers to this ifaddr, destroy it */
inet6_ifa_finish_destroy(struct inet6_ifaddr * ifp)974 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
975 {
976 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
977 
978 #ifdef NET_REFCNT_DEBUG
979 	pr_debug("%s\n", __func__);
980 #endif
981 
982 	in6_dev_put(ifp->idev);
983 
984 	if (cancel_delayed_work(&ifp->dad_work))
985 		pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
986 			  ifp);
987 
988 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
989 		pr_warn("Freeing alive inet6 address %p\n", ifp);
990 		return;
991 	}
992 
993 	kfree_rcu(ifp, rcu);
994 }
995 
996 static void
ipv6_link_dev_addr(struct inet6_dev * idev,struct inet6_ifaddr * ifp)997 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
998 {
999 	struct list_head *p;
1000 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
1001 
1002 	/*
1003 	 * Each device address list is sorted in order of scope -
1004 	 * global before linklocal.
1005 	 */
1006 	list_for_each(p, &idev->addr_list) {
1007 		struct inet6_ifaddr *ifa
1008 			= list_entry(p, struct inet6_ifaddr, if_list);
1009 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
1010 			break;
1011 	}
1012 
1013 	list_add_tail_rcu(&ifp->if_list, p);
1014 }
1015 
inet6_addr_hash(const struct net * net,const struct in6_addr * addr)1016 static u32 inet6_addr_hash(const struct net *net, const struct in6_addr *addr)
1017 {
1018 	u32 val = __ipv6_addr_jhash(addr, net_hash_mix(net));
1019 
1020 	return hash_32(val, IN6_ADDR_HSIZE_SHIFT);
1021 }
1022 
ipv6_chk_same_addr(struct net * net,const struct in6_addr * addr,struct net_device * dev,unsigned int hash)1023 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
1024 			       struct net_device *dev, unsigned int hash)
1025 {
1026 	struct inet6_ifaddr *ifp;
1027 
1028 	hlist_for_each_entry(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
1029 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1030 			if (!dev || ifp->idev->dev == dev)
1031 				return true;
1032 		}
1033 	}
1034 	return false;
1035 }
1036 
ipv6_add_addr_hash(struct net_device * dev,struct inet6_ifaddr * ifa)1037 static int ipv6_add_addr_hash(struct net_device *dev, struct inet6_ifaddr *ifa)
1038 {
1039 	struct net *net = dev_net(dev);
1040 	unsigned int hash = inet6_addr_hash(net, &ifa->addr);
1041 	int err = 0;
1042 
1043 	spin_lock_bh(&net->ipv6.addrconf_hash_lock);
1044 
1045 	/* Ignore adding duplicate addresses on an interface */
1046 	if (ipv6_chk_same_addr(net, &ifa->addr, dev, hash)) {
1047 		netdev_dbg(dev, "ipv6_add_addr: already assigned\n");
1048 		err = -EEXIST;
1049 	} else {
1050 		hlist_add_head_rcu(&ifa->addr_lst, &net->ipv6.inet6_addr_lst[hash]);
1051 	}
1052 
1053 	spin_unlock_bh(&net->ipv6.addrconf_hash_lock);
1054 
1055 	return err;
1056 }
1057 
1058 /* On success it returns ifp with increased reference count */
1059 
1060 static struct inet6_ifaddr *
ipv6_add_addr(struct inet6_dev * idev,struct ifa6_config * cfg,bool can_block,struct netlink_ext_ack * extack)1061 ipv6_add_addr(struct inet6_dev *idev, struct ifa6_config *cfg,
1062 	      bool can_block, struct netlink_ext_ack *extack)
1063 {
1064 	gfp_t gfp_flags = can_block ? GFP_KERNEL : GFP_ATOMIC;
1065 	int addr_type = ipv6_addr_type(cfg->pfx);
1066 	struct net *net = dev_net(idev->dev);
1067 	struct inet6_ifaddr *ifa = NULL;
1068 	struct fib6_info *f6i = NULL;
1069 	int err = 0;
1070 
1071 	if (addr_type == IPV6_ADDR_ANY) {
1072 		NL_SET_ERR_MSG_MOD(extack, "Invalid address");
1073 		return ERR_PTR(-EADDRNOTAVAIL);
1074 	} else if (addr_type & IPV6_ADDR_MULTICAST &&
1075 		   !(cfg->ifa_flags & IFA_F_MCAUTOJOIN)) {
1076 		NL_SET_ERR_MSG_MOD(extack, "Cannot assign multicast address without \"IFA_F_MCAUTOJOIN\" flag");
1077 		return ERR_PTR(-EADDRNOTAVAIL);
1078 	} else if (!(idev->dev->flags & IFF_LOOPBACK) &&
1079 		   !netif_is_l3_master(idev->dev) &&
1080 		   addr_type & IPV6_ADDR_LOOPBACK) {
1081 		NL_SET_ERR_MSG_MOD(extack, "Cannot assign loopback address on this device");
1082 		return ERR_PTR(-EADDRNOTAVAIL);
1083 	}
1084 
1085 	if (idev->dead) {
1086 		NL_SET_ERR_MSG_MOD(extack, "device is going away");
1087 		err = -ENODEV;
1088 		goto out;
1089 	}
1090 
1091 	if (idev->cnf.disable_ipv6) {
1092 		NL_SET_ERR_MSG_MOD(extack, "IPv6 is disabled on this device");
1093 		err = -EACCES;
1094 		goto out;
1095 	}
1096 
1097 	/* validator notifier needs to be blocking;
1098 	 * do not call in atomic context
1099 	 */
1100 	if (can_block) {
1101 		struct in6_validator_info i6vi = {
1102 			.i6vi_addr = *cfg->pfx,
1103 			.i6vi_dev = idev,
1104 			.extack = extack,
1105 		};
1106 
1107 		err = inet6addr_validator_notifier_call_chain(NETDEV_UP, &i6vi);
1108 		err = notifier_to_errno(err);
1109 		if (err < 0)
1110 			goto out;
1111 	}
1112 
1113 	ifa = kzalloc(sizeof(*ifa), gfp_flags | __GFP_ACCOUNT);
1114 	if (!ifa) {
1115 		err = -ENOBUFS;
1116 		goto out;
1117 	}
1118 
1119 	f6i = addrconf_f6i_alloc(net, idev, cfg->pfx, false, gfp_flags, extack);
1120 	if (IS_ERR(f6i)) {
1121 		err = PTR_ERR(f6i);
1122 		f6i = NULL;
1123 		goto out;
1124 	}
1125 
1126 	neigh_parms_data_state_setall(idev->nd_parms);
1127 
1128 	ifa->addr = *cfg->pfx;
1129 	if (cfg->peer_pfx)
1130 		ifa->peer_addr = *cfg->peer_pfx;
1131 
1132 	spin_lock_init(&ifa->lock);
1133 	INIT_DELAYED_WORK(&ifa->dad_work, addrconf_dad_work);
1134 	INIT_HLIST_NODE(&ifa->addr_lst);
1135 	ifa->scope = cfg->scope;
1136 	ifa->prefix_len = cfg->plen;
1137 	ifa->rt_priority = cfg->rt_priority;
1138 	ifa->flags = cfg->ifa_flags;
1139 	ifa->ifa_proto = cfg->ifa_proto;
1140 	/* No need to add the TENTATIVE flag for addresses with NODAD */
1141 	if (!(cfg->ifa_flags & IFA_F_NODAD))
1142 		ifa->flags |= IFA_F_TENTATIVE;
1143 	ifa->valid_lft = cfg->valid_lft;
1144 	ifa->prefered_lft = cfg->preferred_lft;
1145 	ifa->cstamp = ifa->tstamp = jiffies;
1146 	ifa->tokenized = false;
1147 
1148 	ifa->rt = f6i;
1149 
1150 	ifa->idev = idev;
1151 	in6_dev_hold(idev);
1152 
1153 	/* For caller */
1154 	refcount_set(&ifa->refcnt, 1);
1155 
1156 	rcu_read_lock();
1157 
1158 	err = ipv6_add_addr_hash(idev->dev, ifa);
1159 	if (err < 0) {
1160 		rcu_read_unlock();
1161 		goto out;
1162 	}
1163 
1164 	write_lock_bh(&idev->lock);
1165 
1166 	/* Add to inet6_dev unicast addr list. */
1167 	ipv6_link_dev_addr(idev, ifa);
1168 
1169 	if (ifa->flags&IFA_F_TEMPORARY) {
1170 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
1171 		in6_ifa_hold(ifa);
1172 	}
1173 
1174 	in6_ifa_hold(ifa);
1175 	write_unlock_bh(&idev->lock);
1176 
1177 	rcu_read_unlock();
1178 
1179 	inet6addr_notifier_call_chain(NETDEV_UP, ifa);
1180 out:
1181 	if (unlikely(err < 0)) {
1182 		fib6_info_release(f6i);
1183 
1184 		if (ifa) {
1185 			if (ifa->idev)
1186 				in6_dev_put(ifa->idev);
1187 			kfree(ifa);
1188 		}
1189 		ifa = ERR_PTR(err);
1190 	}
1191 
1192 	return ifa;
1193 }
1194 
1195 enum cleanup_prefix_rt_t {
1196 	CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */
1197 	CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */
1198 	CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */
1199 };
1200 
1201 /*
1202  * Check, whether the prefix for ifp would still need a prefix route
1203  * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*
1204  * constants.
1205  *
1206  * 1) we don't purge prefix if address was not permanent.
1207  *    prefix is managed by its own lifetime.
1208  * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.
1209  * 3) if there are no addresses, delete prefix.
1210  * 4) if there are still other permanent address(es),
1211  *    corresponding prefix is still permanent.
1212  * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,
1213  *    don't purge the prefix, assume user space is managing it.
1214  * 6) otherwise, update prefix lifetime to the
1215  *    longest valid lifetime among the corresponding
1216  *    addresses on the device.
1217  *    Note: subsequent RA will update lifetime.
1218  **/
1219 static enum cleanup_prefix_rt_t
check_cleanup_prefix_route(struct inet6_ifaddr * ifp,unsigned long * expires)1220 check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)
1221 {
1222 	struct inet6_ifaddr *ifa;
1223 	struct inet6_dev *idev = ifp->idev;
1224 	unsigned long lifetime;
1225 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;
1226 
1227 	*expires = jiffies;
1228 
1229 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
1230 		if (ifa == ifp)
1231 			continue;
1232 		if (ifa->prefix_len != ifp->prefix_len ||
1233 		    !ipv6_prefix_equal(&ifa->addr, &ifp->addr,
1234 				       ifp->prefix_len))
1235 			continue;
1236 		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
1237 			return CLEANUP_PREFIX_RT_NOP;
1238 
1239 		action = CLEANUP_PREFIX_RT_EXPIRE;
1240 
1241 		spin_lock(&ifa->lock);
1242 
1243 		lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
1244 		/*
1245 		 * Note: Because this address is
1246 		 * not permanent, lifetime <
1247 		 * LONG_MAX / HZ here.
1248 		 */
1249 		if (time_before(*expires, ifa->tstamp + lifetime * HZ))
1250 			*expires = ifa->tstamp + lifetime * HZ;
1251 		spin_unlock(&ifa->lock);
1252 	}
1253 
1254 	return action;
1255 }
1256 
1257 static void
cleanup_prefix_route(struct inet6_ifaddr * ifp,unsigned long expires,bool del_rt,bool del_peer)1258 cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires,
1259 		     bool del_rt, bool del_peer)
1260 {
1261 	struct fib6_table *table;
1262 	struct fib6_info *f6i;
1263 
1264 	f6i = addrconf_get_prefix_route(del_peer ? &ifp->peer_addr : &ifp->addr,
1265 					ifp->prefix_len,
1266 					ifp->idev->dev, 0, RTF_DEFAULT, true);
1267 	if (f6i) {
1268 		if (del_rt)
1269 			ip6_del_rt(dev_net(ifp->idev->dev), f6i, false);
1270 		else {
1271 			if (!(f6i->fib6_flags & RTF_EXPIRES)) {
1272 				table = f6i->fib6_table;
1273 				spin_lock_bh(&table->tb6_lock);
1274 
1275 				fib6_set_expires(f6i, expires);
1276 				fib6_add_gc_list(f6i);
1277 
1278 				spin_unlock_bh(&table->tb6_lock);
1279 			}
1280 			fib6_info_release(f6i);
1281 		}
1282 	}
1283 }
1284 
1285 
1286 /* This function wants to get referenced ifp and releases it before return */
1287 
ipv6_del_addr(struct inet6_ifaddr * ifp)1288 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
1289 {
1290 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;
1291 	struct net *net = dev_net(ifp->idev->dev);
1292 	unsigned long expires;
1293 	int state;
1294 
1295 	ASSERT_RTNL();
1296 
1297 	spin_lock_bh(&ifp->lock);
1298 	state = ifp->state;
1299 	ifp->state = INET6_IFADDR_STATE_DEAD;
1300 	spin_unlock_bh(&ifp->lock);
1301 
1302 	if (state == INET6_IFADDR_STATE_DEAD)
1303 		goto out;
1304 
1305 	spin_lock_bh(&net->ipv6.addrconf_hash_lock);
1306 	hlist_del_init_rcu(&ifp->addr_lst);
1307 	spin_unlock_bh(&net->ipv6.addrconf_hash_lock);
1308 
1309 	write_lock_bh(&ifp->idev->lock);
1310 
1311 	if (ifp->flags&IFA_F_TEMPORARY) {
1312 		list_del(&ifp->tmp_list);
1313 		if (ifp->ifpub) {
1314 			in6_ifa_put(ifp->ifpub);
1315 			ifp->ifpub = NULL;
1316 		}
1317 		__in6_ifa_put(ifp);
1318 	}
1319 
1320 	if (ifp->flags & IFA_F_PERMANENT && !(ifp->flags & IFA_F_NOPREFIXROUTE))
1321 		action = check_cleanup_prefix_route(ifp, &expires);
1322 
1323 	list_del_rcu(&ifp->if_list);
1324 	__in6_ifa_put(ifp);
1325 
1326 	write_unlock_bh(&ifp->idev->lock);
1327 
1328 	addrconf_del_dad_work(ifp);
1329 
1330 	ipv6_ifa_notify(RTM_DELADDR, ifp);
1331 
1332 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
1333 
1334 	if (action != CLEANUP_PREFIX_RT_NOP) {
1335 		cleanup_prefix_route(ifp, expires,
1336 			action == CLEANUP_PREFIX_RT_DEL, false);
1337 	}
1338 
1339 	/* clean up prefsrc entries */
1340 	rt6_remove_prefsrc(ifp);
1341 out:
1342 	in6_ifa_put(ifp);
1343 }
1344 
ipv6_get_regen_advance(const struct inet6_dev * idev)1345 static unsigned long ipv6_get_regen_advance(const struct inet6_dev *idev)
1346 {
1347 	return READ_ONCE(idev->cnf.regen_min_advance) +
1348 		READ_ONCE(idev->cnf.regen_max_retry) *
1349 		READ_ONCE(idev->cnf.dad_transmits) *
1350 		max(NEIGH_VAR(idev->nd_parms, RETRANS_TIME), HZ/100) / HZ;
1351 }
1352 
ipv6_create_tempaddr(struct inet6_ifaddr * ifp,bool block)1353 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, bool block)
1354 {
1355 	struct inet6_dev *idev = ifp->idev;
1356 	unsigned long tmp_tstamp, age;
1357 	unsigned long regen_advance;
1358 	unsigned long now = jiffies;
1359 	u32 if_public_preferred_lft;
1360 	s32 cnf_temp_preferred_lft;
1361 	struct inet6_ifaddr *ift;
1362 	struct ifa6_config cfg;
1363 	long max_desync_factor;
1364 	struct in6_addr addr;
1365 	int ret = 0;
1366 
1367 	write_lock_bh(&idev->lock);
1368 
1369 retry:
1370 	in6_dev_hold(idev);
1371 	if (READ_ONCE(idev->cnf.use_tempaddr) <= 0) {
1372 		write_unlock_bh(&idev->lock);
1373 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1374 		in6_dev_put(idev);
1375 		ret = -1;
1376 		goto out;
1377 	}
1378 	spin_lock_bh(&ifp->lock);
1379 	if (ifp->regen_count++ >= READ_ONCE(idev->cnf.regen_max_retry)) {
1380 		WRITE_ONCE(idev->cnf.use_tempaddr, -1);	/*XXX*/
1381 		spin_unlock_bh(&ifp->lock);
1382 		write_unlock_bh(&idev->lock);
1383 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1384 			__func__);
1385 		in6_dev_put(idev);
1386 		ret = -1;
1387 		goto out;
1388 	}
1389 	in6_ifa_hold(ifp);
1390 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1391 	ipv6_gen_rnd_iid(&addr);
1392 
1393 	age = (now - ifp->tstamp) / HZ;
1394 
1395 	regen_advance = ipv6_get_regen_advance(idev);
1396 
1397 	/* recalculate max_desync_factor each time and update
1398 	 * idev->desync_factor if it's larger
1399 	 */
1400 	cnf_temp_preferred_lft = READ_ONCE(idev->cnf.temp_prefered_lft);
1401 	max_desync_factor = min_t(long,
1402 				  READ_ONCE(idev->cnf.max_desync_factor),
1403 				  cnf_temp_preferred_lft - regen_advance);
1404 
1405 	if (unlikely(idev->desync_factor > max_desync_factor)) {
1406 		if (max_desync_factor > 0) {
1407 			get_random_bytes(&idev->desync_factor,
1408 					 sizeof(idev->desync_factor));
1409 			idev->desync_factor %= max_desync_factor;
1410 		} else {
1411 			idev->desync_factor = 0;
1412 		}
1413 	}
1414 
1415 	if_public_preferred_lft = ifp->prefered_lft;
1416 
1417 	memset(&cfg, 0, sizeof(cfg));
1418 	cfg.valid_lft = min_t(__u32, ifp->valid_lft,
1419 			      READ_ONCE(idev->cnf.temp_valid_lft) + age);
1420 	cfg.preferred_lft = cnf_temp_preferred_lft + age - idev->desync_factor;
1421 	cfg.preferred_lft = min_t(__u32, if_public_preferred_lft, cfg.preferred_lft);
1422 	cfg.preferred_lft = min_t(__u32, cfg.valid_lft, cfg.preferred_lft);
1423 
1424 	cfg.plen = ifp->prefix_len;
1425 	tmp_tstamp = ifp->tstamp;
1426 	spin_unlock_bh(&ifp->lock);
1427 
1428 	write_unlock_bh(&idev->lock);
1429 
1430 	/* From RFC 4941:
1431 	 *
1432 	 *     A temporary address is created only if this calculated Preferred
1433 	 *     Lifetime is greater than REGEN_ADVANCE time units.  In
1434 	 *     particular, an implementation must not create a temporary address
1435 	 *     with a zero Preferred Lifetime.
1436 	 *
1437 	 *     ...
1438 	 *
1439 	 *     When creating a temporary address, the lifetime values MUST be
1440 	 *     derived from the corresponding prefix as follows:
1441 	 *
1442 	 *     ...
1443 	 *
1444 	 *     *  Its Preferred Lifetime is the lower of the Preferred Lifetime
1445 	 *        of the public address or TEMP_PREFERRED_LIFETIME -
1446 	 *        DESYNC_FACTOR.
1447 	 *
1448 	 * To comply with the RFC's requirements, clamp the preferred lifetime
1449 	 * to a minimum of regen_advance, unless that would exceed valid_lft or
1450 	 * ifp->prefered_lft.
1451 	 *
1452 	 * Use age calculation as in addrconf_verify to avoid unnecessary
1453 	 * temporary addresses being generated.
1454 	 */
1455 	age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1456 	if (cfg.preferred_lft <= regen_advance + age) {
1457 		cfg.preferred_lft = regen_advance + age + 1;
1458 		if (cfg.preferred_lft > cfg.valid_lft ||
1459 		    cfg.preferred_lft > if_public_preferred_lft) {
1460 			in6_ifa_put(ifp);
1461 			in6_dev_put(idev);
1462 			ret = -1;
1463 			goto out;
1464 		}
1465 	}
1466 
1467 	cfg.ifa_flags = IFA_F_TEMPORARY;
1468 	/* set in addrconf_prefix_rcv() */
1469 	if (ifp->flags & IFA_F_OPTIMISTIC)
1470 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
1471 
1472 	cfg.pfx = &addr;
1473 	cfg.scope = ipv6_addr_scope(cfg.pfx);
1474 
1475 	ift = ipv6_add_addr(idev, &cfg, block, NULL);
1476 	if (IS_ERR(ift)) {
1477 		in6_ifa_put(ifp);
1478 		in6_dev_put(idev);
1479 		pr_info("%s: retry temporary address regeneration\n", __func__);
1480 		write_lock_bh(&idev->lock);
1481 		goto retry;
1482 	}
1483 
1484 	spin_lock_bh(&ift->lock);
1485 	ift->ifpub = ifp;
1486 	ift->cstamp = now;
1487 	ift->tstamp = tmp_tstamp;
1488 	spin_unlock_bh(&ift->lock);
1489 
1490 	addrconf_dad_start(ift);
1491 	in6_ifa_put(ift);
1492 	in6_dev_put(idev);
1493 out:
1494 	return ret;
1495 }
1496 
1497 /*
1498  *	Choose an appropriate source address (RFC3484)
1499  */
1500 enum {
1501 	IPV6_SADDR_RULE_INIT = 0,
1502 	IPV6_SADDR_RULE_LOCAL,
1503 	IPV6_SADDR_RULE_SCOPE,
1504 	IPV6_SADDR_RULE_PREFERRED,
1505 #ifdef CONFIG_IPV6_MIP6
1506 	IPV6_SADDR_RULE_HOA,
1507 #endif
1508 	IPV6_SADDR_RULE_OIF,
1509 	IPV6_SADDR_RULE_LABEL,
1510 	IPV6_SADDR_RULE_PRIVACY,
1511 	IPV6_SADDR_RULE_ORCHID,
1512 	IPV6_SADDR_RULE_PREFIX,
1513 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1514 	IPV6_SADDR_RULE_NOT_OPTIMISTIC,
1515 #endif
1516 	IPV6_SADDR_RULE_MAX
1517 };
1518 
1519 struct ipv6_saddr_score {
1520 	int			rule;
1521 	int			addr_type;
1522 	struct inet6_ifaddr	*ifa;
1523 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1524 	int			scopedist;
1525 	int			matchlen;
1526 };
1527 
1528 struct ipv6_saddr_dst {
1529 	const struct in6_addr *addr;
1530 	int ifindex;
1531 	int scope;
1532 	int label;
1533 	unsigned int prefs;
1534 };
1535 
ipv6_saddr_preferred(int type)1536 static inline int ipv6_saddr_preferred(int type)
1537 {
1538 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1539 		return 1;
1540 	return 0;
1541 }
1542 
ipv6_use_optimistic_addr(const struct net * net,const struct inet6_dev * idev)1543 static bool ipv6_use_optimistic_addr(const struct net *net,
1544 				     const struct inet6_dev *idev)
1545 {
1546 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1547 	if (!idev)
1548 		return false;
1549 	if (!READ_ONCE(net->ipv6.devconf_all->optimistic_dad) &&
1550 	    !READ_ONCE(idev->cnf.optimistic_dad))
1551 		return false;
1552 	if (!READ_ONCE(net->ipv6.devconf_all->use_optimistic) &&
1553 	    !READ_ONCE(idev->cnf.use_optimistic))
1554 		return false;
1555 
1556 	return true;
1557 #else
1558 	return false;
1559 #endif
1560 }
1561 
ipv6_allow_optimistic_dad(const struct net * net,const struct inet6_dev * idev)1562 static bool ipv6_allow_optimistic_dad(const struct net *net,
1563 				      const struct inet6_dev *idev)
1564 {
1565 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1566 	if (!idev)
1567 		return false;
1568 	if (!READ_ONCE(net->ipv6.devconf_all->optimistic_dad) &&
1569 	    !READ_ONCE(idev->cnf.optimistic_dad))
1570 		return false;
1571 
1572 	return true;
1573 #else
1574 	return false;
1575 #endif
1576 }
1577 
ipv6_get_saddr_eval(struct net * net,struct ipv6_saddr_score * score,struct ipv6_saddr_dst * dst,int i)1578 static int ipv6_get_saddr_eval(struct net *net,
1579 			       struct ipv6_saddr_score *score,
1580 			       struct ipv6_saddr_dst *dst,
1581 			       int i)
1582 {
1583 	int ret;
1584 
1585 	if (i <= score->rule) {
1586 		switch (i) {
1587 		case IPV6_SADDR_RULE_SCOPE:
1588 			ret = score->scopedist;
1589 			break;
1590 		case IPV6_SADDR_RULE_PREFIX:
1591 			ret = score->matchlen;
1592 			break;
1593 		default:
1594 			ret = !!test_bit(i, score->scorebits);
1595 		}
1596 		goto out;
1597 	}
1598 
1599 	switch (i) {
1600 	case IPV6_SADDR_RULE_INIT:
1601 		/* Rule 0: remember if hiscore is not ready yet */
1602 		ret = !!score->ifa;
1603 		break;
1604 	case IPV6_SADDR_RULE_LOCAL:
1605 		/* Rule 1: Prefer same address */
1606 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1607 		break;
1608 	case IPV6_SADDR_RULE_SCOPE:
1609 		/* Rule 2: Prefer appropriate scope
1610 		 *
1611 		 *      ret
1612 		 *       ^
1613 		 *    -1 |  d 15
1614 		 *    ---+--+-+---> scope
1615 		 *       |
1616 		 *       |             d is scope of the destination.
1617 		 *  B-d  |  \
1618 		 *       |   \      <- smaller scope is better if
1619 		 *  B-15 |    \        if scope is enough for destination.
1620 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1621 		 * d-C-1 | /
1622 		 *       |/         <- greater is better
1623 		 *   -C  /             if scope is not enough for destination.
1624 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1625 		 *
1626 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1627 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1628 		 * Assume B = 0 and we get C > 29.
1629 		 */
1630 		ret = __ipv6_addr_src_scope(score->addr_type);
1631 		if (ret >= dst->scope)
1632 			ret = -ret;
1633 		else
1634 			ret -= 128;	/* 30 is enough */
1635 		score->scopedist = ret;
1636 		break;
1637 	case IPV6_SADDR_RULE_PREFERRED:
1638 	    {
1639 		/* Rule 3: Avoid deprecated and optimistic addresses */
1640 		u8 avoid = IFA_F_DEPRECATED;
1641 
1642 		if (!ipv6_use_optimistic_addr(net, score->ifa->idev))
1643 			avoid |= IFA_F_OPTIMISTIC;
1644 		ret = ipv6_saddr_preferred(score->addr_type) ||
1645 		      !(score->ifa->flags & avoid);
1646 		break;
1647 	    }
1648 #ifdef CONFIG_IPV6_MIP6
1649 	case IPV6_SADDR_RULE_HOA:
1650 	    {
1651 		/* Rule 4: Prefer home address */
1652 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1653 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1654 		break;
1655 	    }
1656 #endif
1657 	case IPV6_SADDR_RULE_OIF:
1658 		/* Rule 5: Prefer outgoing interface */
1659 		ret = (!dst->ifindex ||
1660 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1661 		break;
1662 	case IPV6_SADDR_RULE_LABEL:
1663 		/* Rule 6: Prefer matching label */
1664 		ret = ipv6_addr_label(net,
1665 				      &score->ifa->addr, score->addr_type,
1666 				      score->ifa->idev->dev->ifindex) == dst->label;
1667 		break;
1668 	case IPV6_SADDR_RULE_PRIVACY:
1669 	    {
1670 		/* Rule 7: Prefer public address
1671 		 * Note: prefer temporary address if use_tempaddr >= 2
1672 		 */
1673 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1674 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1675 				READ_ONCE(score->ifa->idev->cnf.use_tempaddr) >= 2;
1676 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1677 		break;
1678 	    }
1679 	case IPV6_SADDR_RULE_ORCHID:
1680 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1681 		 *	    non-ORCHID vs non-ORCHID
1682 		 */
1683 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1684 			ipv6_addr_orchid(dst->addr));
1685 		break;
1686 	case IPV6_SADDR_RULE_PREFIX:
1687 		/* Rule 8: Use longest matching prefix */
1688 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1689 		if (ret > score->ifa->prefix_len)
1690 			ret = score->ifa->prefix_len;
1691 		score->matchlen = ret;
1692 		break;
1693 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1694 	case IPV6_SADDR_RULE_NOT_OPTIMISTIC:
1695 		/* Optimistic addresses still have lower precedence than other
1696 		 * preferred addresses.
1697 		 */
1698 		ret = !(score->ifa->flags & IFA_F_OPTIMISTIC);
1699 		break;
1700 #endif
1701 	default:
1702 		ret = 0;
1703 	}
1704 
1705 	if (ret)
1706 		__set_bit(i, score->scorebits);
1707 	score->rule = i;
1708 out:
1709 	return ret;
1710 }
1711 
__ipv6_dev_get_saddr(struct net * net,struct ipv6_saddr_dst * dst,struct inet6_dev * idev,struct ipv6_saddr_score * scores,int hiscore_idx)1712 static int __ipv6_dev_get_saddr(struct net *net,
1713 				struct ipv6_saddr_dst *dst,
1714 				struct inet6_dev *idev,
1715 				struct ipv6_saddr_score *scores,
1716 				int hiscore_idx)
1717 {
1718 	struct ipv6_saddr_score *score = &scores[1 - hiscore_idx], *hiscore = &scores[hiscore_idx];
1719 
1720 	list_for_each_entry_rcu(score->ifa, &idev->addr_list, if_list) {
1721 		int i;
1722 
1723 		/*
1724 		 * - Tentative Address (RFC2462 section 5.4)
1725 		 *  - A tentative address is not considered
1726 		 *    "assigned to an interface" in the traditional
1727 		 *    sense, unless it is also flagged as optimistic.
1728 		 * - Candidate Source Address (section 4)
1729 		 *  - In any case, anycast addresses, multicast
1730 		 *    addresses, and the unspecified address MUST
1731 		 *    NOT be included in a candidate set.
1732 		 */
1733 		if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1734 		    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1735 			continue;
1736 
1737 		score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1738 
1739 		if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1740 			     score->addr_type & IPV6_ADDR_MULTICAST)) {
1741 			net_dbg_ratelimited("ADDRCONF: unspecified / multicast address assigned as unicast address on %s",
1742 					    idev->dev->name);
1743 			continue;
1744 		}
1745 
1746 		score->rule = -1;
1747 		bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1748 
1749 		for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1750 			int minihiscore, miniscore;
1751 
1752 			minihiscore = ipv6_get_saddr_eval(net, hiscore, dst, i);
1753 			miniscore = ipv6_get_saddr_eval(net, score, dst, i);
1754 
1755 			if (minihiscore > miniscore) {
1756 				if (i == IPV6_SADDR_RULE_SCOPE &&
1757 				    score->scopedist > 0) {
1758 					/*
1759 					 * special case:
1760 					 * each remaining entry
1761 					 * has too small (not enough)
1762 					 * scope, because ifa entries
1763 					 * are sorted by their scope
1764 					 * values.
1765 					 */
1766 					goto out;
1767 				}
1768 				break;
1769 			} else if (minihiscore < miniscore) {
1770 				swap(hiscore, score);
1771 				hiscore_idx = 1 - hiscore_idx;
1772 
1773 				/* restore our iterator */
1774 				score->ifa = hiscore->ifa;
1775 
1776 				break;
1777 			}
1778 		}
1779 	}
1780 out:
1781 	return hiscore_idx;
1782 }
1783 
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)1784 static int ipv6_get_saddr_master(struct net *net,
1785 				 const struct net_device *dst_dev,
1786 				 const struct net_device *master,
1787 				 struct ipv6_saddr_dst *dst,
1788 				 struct ipv6_saddr_score *scores,
1789 				 int hiscore_idx)
1790 {
1791 	struct inet6_dev *idev;
1792 
1793 	idev = __in6_dev_get(dst_dev);
1794 	if (idev)
1795 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1796 						   scores, hiscore_idx);
1797 
1798 	idev = __in6_dev_get(master);
1799 	if (idev)
1800 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1801 						   scores, hiscore_idx);
1802 
1803 	return hiscore_idx;
1804 }
1805 
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)1806 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1807 		       const struct in6_addr *daddr, unsigned int prefs,
1808 		       struct in6_addr *saddr)
1809 {
1810 	struct ipv6_saddr_score scores[2], *hiscore;
1811 	struct ipv6_saddr_dst dst;
1812 	struct inet6_dev *idev;
1813 	struct net_device *dev;
1814 	int dst_type;
1815 	bool use_oif_addr = false;
1816 	int hiscore_idx = 0;
1817 	int ret = 0;
1818 
1819 	dst_type = __ipv6_addr_type(daddr);
1820 	dst.addr = daddr;
1821 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1822 	dst.scope = __ipv6_addr_src_scope(dst_type);
1823 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1824 	dst.prefs = prefs;
1825 
1826 	scores[hiscore_idx].rule = -1;
1827 	scores[hiscore_idx].ifa = NULL;
1828 
1829 	rcu_read_lock();
1830 
1831 	/* Candidate Source Address (section 4)
1832 	 *  - multicast and link-local destination address,
1833 	 *    the set of candidate source address MUST only
1834 	 *    include addresses assigned to interfaces
1835 	 *    belonging to the same link as the outgoing
1836 	 *    interface.
1837 	 * (- For site-local destination addresses, the
1838 	 *    set of candidate source addresses MUST only
1839 	 *    include addresses assigned to interfaces
1840 	 *    belonging to the same site as the outgoing
1841 	 *    interface.)
1842 	 *  - "It is RECOMMENDED that the candidate source addresses
1843 	 *    be the set of unicast addresses assigned to the
1844 	 *    interface that will be used to send to the destination
1845 	 *    (the 'outgoing' interface)." (RFC 6724)
1846 	 */
1847 	if (dst_dev) {
1848 		idev = __in6_dev_get(dst_dev);
1849 		if ((dst_type & IPV6_ADDR_MULTICAST) ||
1850 		    dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL ||
1851 		    (idev && READ_ONCE(idev->cnf.use_oif_addrs_only))) {
1852 			use_oif_addr = true;
1853 		}
1854 	}
1855 
1856 	if (use_oif_addr) {
1857 		if (idev)
1858 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1859 	} else {
1860 		const struct net_device *master;
1861 		int master_idx = 0;
1862 
1863 		/* if dst_dev exists and is enslaved to an L3 device, then
1864 		 * prefer addresses from dst_dev and then the master over
1865 		 * any other enslaved devices in the L3 domain.
1866 		 */
1867 		master = l3mdev_master_dev_rcu(dst_dev);
1868 		if (master) {
1869 			master_idx = master->ifindex;
1870 
1871 			hiscore_idx = ipv6_get_saddr_master(net, dst_dev,
1872 							    master, &dst,
1873 							    scores, hiscore_idx);
1874 
1875 			if (scores[hiscore_idx].ifa &&
1876 			    scores[hiscore_idx].scopedist >= 0)
1877 				goto out;
1878 		}
1879 
1880 		for_each_netdev_rcu(net, dev) {
1881 			/* only consider addresses on devices in the
1882 			 * same L3 domain
1883 			 */
1884 			if (l3mdev_master_ifindex_rcu(dev) != master_idx)
1885 				continue;
1886 			idev = __in6_dev_get(dev);
1887 			if (!idev)
1888 				continue;
1889 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1890 		}
1891 	}
1892 
1893 out:
1894 	hiscore = &scores[hiscore_idx];
1895 	if (!hiscore->ifa)
1896 		ret = -EADDRNOTAVAIL;
1897 	else
1898 		*saddr = hiscore->ifa->addr;
1899 
1900 	rcu_read_unlock();
1901 	return ret;
1902 }
1903 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1904 
__ipv6_get_lladdr(struct inet6_dev * idev,struct in6_addr * addr,u32 banned_flags)1905 static int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1906 			      u32 banned_flags)
1907 {
1908 	struct inet6_ifaddr *ifp;
1909 	int err = -EADDRNOTAVAIL;
1910 
1911 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1912 		if (ifp->scope > IFA_LINK)
1913 			break;
1914 		if (ifp->scope == IFA_LINK &&
1915 		    !(ifp->flags & banned_flags)) {
1916 			*addr = ifp->addr;
1917 			err = 0;
1918 			break;
1919 		}
1920 	}
1921 	return err;
1922 }
1923 
ipv6_get_lladdr(struct net_device * dev,struct in6_addr * addr,u32 banned_flags)1924 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1925 		    u32 banned_flags)
1926 {
1927 	struct inet6_dev *idev;
1928 	int err = -EADDRNOTAVAIL;
1929 
1930 	rcu_read_lock();
1931 	idev = __in6_dev_get(dev);
1932 	if (idev) {
1933 		read_lock_bh(&idev->lock);
1934 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1935 		read_unlock_bh(&idev->lock);
1936 	}
1937 	rcu_read_unlock();
1938 	return err;
1939 }
1940 
ipv6_count_addresses(const struct inet6_dev * idev)1941 static int ipv6_count_addresses(const struct inet6_dev *idev)
1942 {
1943 	const struct inet6_ifaddr *ifp;
1944 	int cnt = 0;
1945 
1946 	rcu_read_lock();
1947 	list_for_each_entry_rcu(ifp, &idev->addr_list, if_list)
1948 		cnt++;
1949 	rcu_read_unlock();
1950 	return cnt;
1951 }
1952 
ipv6_chk_addr(struct net * net,const struct in6_addr * addr,const struct net_device * dev,int strict)1953 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1954 		  const struct net_device *dev, int strict)
1955 {
1956 	return ipv6_chk_addr_and_flags(net, addr, dev, !dev,
1957 				       strict, IFA_F_TENTATIVE);
1958 }
1959 EXPORT_SYMBOL(ipv6_chk_addr);
1960 
1961 /* device argument is used to find the L3 domain of interest. If
1962  * skip_dev_check is set, then the ifp device is not checked against
1963  * the passed in dev argument. So the 2 cases for addresses checks are:
1964  *   1. does the address exist in the L3 domain that dev is part of
1965  *      (skip_dev_check = true), or
1966  *
1967  *   2. does the address exist on the specific device
1968  *      (skip_dev_check = false)
1969  */
1970 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)1971 __ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1972 			  const struct net_device *dev, bool skip_dev_check,
1973 			  int strict, u32 banned_flags)
1974 {
1975 	unsigned int hash = inet6_addr_hash(net, addr);
1976 	struct net_device *l3mdev, *ndev;
1977 	struct inet6_ifaddr *ifp;
1978 	u32 ifp_flags;
1979 
1980 	rcu_read_lock();
1981 
1982 	l3mdev = l3mdev_master_dev_rcu(dev);
1983 	if (skip_dev_check)
1984 		dev = NULL;
1985 
1986 	hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
1987 		ndev = ifp->idev->dev;
1988 
1989 		if (l3mdev_master_dev_rcu(ndev) != l3mdev)
1990 			continue;
1991 
1992 		/* Decouple optimistic from tentative for evaluation here.
1993 		 * Ban optimistic addresses explicitly, when required.
1994 		 */
1995 		ifp_flags = (ifp->flags&IFA_F_OPTIMISTIC)
1996 			    ? (ifp->flags&~IFA_F_TENTATIVE)
1997 			    : ifp->flags;
1998 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1999 		    !(ifp_flags&banned_flags) &&
2000 		    (!dev || ndev == dev ||
2001 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
2002 			rcu_read_unlock();
2003 			return ndev;
2004 		}
2005 	}
2006 
2007 	rcu_read_unlock();
2008 	return NULL;
2009 }
2010 
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)2011 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
2012 			    const struct net_device *dev, bool skip_dev_check,
2013 			    int strict, u32 banned_flags)
2014 {
2015 	return __ipv6_chk_addr_and_flags(net, addr, dev, skip_dev_check,
2016 					 strict, banned_flags) ? 1 : 0;
2017 }
2018 EXPORT_SYMBOL(ipv6_chk_addr_and_flags);
2019 
2020 
2021 /* Compares an address/prefix_len with addresses on device @dev.
2022  * If one is found it returns true.
2023  */
ipv6_chk_custom_prefix(const struct in6_addr * addr,const unsigned int prefix_len,struct net_device * dev)2024 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
2025 	const unsigned int prefix_len, struct net_device *dev)
2026 {
2027 	const struct inet6_ifaddr *ifa;
2028 	const struct inet6_dev *idev;
2029 	bool ret = false;
2030 
2031 	rcu_read_lock();
2032 	idev = __in6_dev_get(dev);
2033 	if (idev) {
2034 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
2035 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
2036 			if (ret)
2037 				break;
2038 		}
2039 	}
2040 	rcu_read_unlock();
2041 
2042 	return ret;
2043 }
2044 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
2045 
ipv6_chk_prefix(const struct in6_addr * addr,struct net_device * dev)2046 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
2047 {
2048 	const struct inet6_ifaddr *ifa;
2049 	const struct inet6_dev *idev;
2050 	int	onlink;
2051 
2052 	onlink = 0;
2053 	rcu_read_lock();
2054 	idev = __in6_dev_get(dev);
2055 	if (idev) {
2056 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
2057 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
2058 						   ifa->prefix_len);
2059 			if (onlink)
2060 				break;
2061 		}
2062 	}
2063 	rcu_read_unlock();
2064 	return onlink;
2065 }
2066 EXPORT_SYMBOL(ipv6_chk_prefix);
2067 
2068 /**
2069  * ipv6_dev_find - find the first device with a given source address.
2070  * @net: the net namespace
2071  * @addr: the source address
2072  * @dev: used to find the L3 domain of interest
2073  *
2074  * The caller should be protected by RCU, or RTNL.
2075  */
ipv6_dev_find(struct net * net,const struct in6_addr * addr,struct net_device * dev)2076 struct net_device *ipv6_dev_find(struct net *net, const struct in6_addr *addr,
2077 				 struct net_device *dev)
2078 {
2079 	return __ipv6_chk_addr_and_flags(net, addr, dev, !dev, 1,
2080 					 IFA_F_TENTATIVE);
2081 }
2082 EXPORT_SYMBOL(ipv6_dev_find);
2083 
ipv6_get_ifaddr(struct net * net,const struct in6_addr * addr,struct net_device * dev,int strict)2084 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
2085 				     struct net_device *dev, int strict)
2086 {
2087 	unsigned int hash = inet6_addr_hash(net, addr);
2088 	struct inet6_ifaddr *ifp, *result = NULL;
2089 
2090 	rcu_read_lock();
2091 	hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
2092 		if (ipv6_addr_equal(&ifp->addr, addr)) {
2093 			if (!dev || ifp->idev->dev == dev ||
2094 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
2095 				if (in6_ifa_hold_safe(ifp)) {
2096 					result = ifp;
2097 					break;
2098 				}
2099 			}
2100 		}
2101 	}
2102 	rcu_read_unlock();
2103 
2104 	return result;
2105 }
2106 
2107 /* Gets referenced address, destroys ifaddr */
2108 
addrconf_dad_stop(struct inet6_ifaddr * ifp,int dad_failed)2109 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
2110 {
2111 	if (dad_failed)
2112 		ifp->flags |= IFA_F_DADFAILED;
2113 
2114 	if (ifp->flags&IFA_F_TEMPORARY) {
2115 		struct inet6_ifaddr *ifpub;
2116 		spin_lock_bh(&ifp->lock);
2117 		ifpub = ifp->ifpub;
2118 		if (ifpub) {
2119 			in6_ifa_hold(ifpub);
2120 			spin_unlock_bh(&ifp->lock);
2121 			ipv6_create_tempaddr(ifpub, true);
2122 			in6_ifa_put(ifpub);
2123 		} else {
2124 			spin_unlock_bh(&ifp->lock);
2125 		}
2126 		ipv6_del_addr(ifp);
2127 	} else if (ifp->flags&IFA_F_PERMANENT || !dad_failed) {
2128 		spin_lock_bh(&ifp->lock);
2129 		addrconf_del_dad_work(ifp);
2130 		ifp->flags |= IFA_F_TENTATIVE;
2131 		if (dad_failed)
2132 			ifp->flags &= ~IFA_F_OPTIMISTIC;
2133 		spin_unlock_bh(&ifp->lock);
2134 		if (dad_failed)
2135 			ipv6_ifa_notify(0, ifp);
2136 		in6_ifa_put(ifp);
2137 	} else {
2138 		ipv6_del_addr(ifp);
2139 	}
2140 }
2141 
addrconf_dad_end(struct inet6_ifaddr * ifp)2142 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
2143 {
2144 	int err = -ENOENT;
2145 
2146 	spin_lock_bh(&ifp->lock);
2147 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
2148 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
2149 		err = 0;
2150 	}
2151 	spin_unlock_bh(&ifp->lock);
2152 
2153 	return err;
2154 }
2155 
addrconf_dad_failure(struct sk_buff * skb,struct inet6_ifaddr * ifp)2156 void addrconf_dad_failure(struct sk_buff *skb, struct inet6_ifaddr *ifp)
2157 {
2158 	struct inet6_dev *idev = ifp->idev;
2159 	struct net *net = dev_net(idev->dev);
2160 	int max_addresses;
2161 
2162 	if (addrconf_dad_end(ifp)) {
2163 		in6_ifa_put(ifp);
2164 		return;
2165 	}
2166 
2167 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c used by %pM detected!\n",
2168 			     ifp->idev->dev->name, &ifp->addr, eth_hdr(skb)->h_source);
2169 
2170 	spin_lock_bh(&ifp->lock);
2171 
2172 	if (ifp->flags & IFA_F_STABLE_PRIVACY) {
2173 		struct in6_addr new_addr;
2174 		struct inet6_ifaddr *ifp2;
2175 		int retries = ifp->stable_privacy_retry + 1;
2176 		struct ifa6_config cfg = {
2177 			.pfx = &new_addr,
2178 			.plen = ifp->prefix_len,
2179 			.ifa_flags = ifp->flags,
2180 			.valid_lft = ifp->valid_lft,
2181 			.preferred_lft = ifp->prefered_lft,
2182 			.scope = ifp->scope,
2183 		};
2184 
2185 		if (retries > net->ipv6.sysctl.idgen_retries) {
2186 			net_info_ratelimited("%s: privacy stable address generation failed because of DAD conflicts!\n",
2187 					     ifp->idev->dev->name);
2188 			goto errdad;
2189 		}
2190 
2191 		new_addr = ifp->addr;
2192 		if (ipv6_generate_stable_address(&new_addr, retries,
2193 						 idev))
2194 			goto errdad;
2195 
2196 		spin_unlock_bh(&ifp->lock);
2197 
2198 		max_addresses = READ_ONCE(idev->cnf.max_addresses);
2199 		if (max_addresses &&
2200 		    ipv6_count_addresses(idev) >= max_addresses)
2201 			goto lock_errdad;
2202 
2203 		net_info_ratelimited("%s: generating new stable privacy address because of DAD conflict\n",
2204 				     ifp->idev->dev->name);
2205 
2206 		ifp2 = ipv6_add_addr(idev, &cfg, false, NULL);
2207 		if (IS_ERR(ifp2))
2208 			goto lock_errdad;
2209 
2210 		spin_lock_bh(&ifp2->lock);
2211 		ifp2->stable_privacy_retry = retries;
2212 		ifp2->state = INET6_IFADDR_STATE_PREDAD;
2213 		spin_unlock_bh(&ifp2->lock);
2214 
2215 		addrconf_mod_dad_work(ifp2, net->ipv6.sysctl.idgen_delay);
2216 		in6_ifa_put(ifp2);
2217 lock_errdad:
2218 		spin_lock_bh(&ifp->lock);
2219 	}
2220 
2221 errdad:
2222 	/* transition from _POSTDAD to _ERRDAD */
2223 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
2224 	spin_unlock_bh(&ifp->lock);
2225 
2226 	addrconf_mod_dad_work(ifp, 0);
2227 	in6_ifa_put(ifp);
2228 }
2229 
2230 /* Join to solicited addr multicast group.
2231  * caller must hold RTNL */
addrconf_join_solict(struct net_device * dev,const struct in6_addr * addr)2232 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
2233 {
2234 	struct in6_addr maddr;
2235 
2236 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2237 		return;
2238 
2239 	addrconf_addr_solict_mult(addr, &maddr);
2240 	ipv6_dev_mc_inc(dev, &maddr);
2241 }
2242 
2243 /* caller must hold RTNL */
addrconf_leave_solict(struct inet6_dev * idev,const struct in6_addr * addr)2244 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
2245 {
2246 	struct in6_addr maddr;
2247 
2248 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2249 		return;
2250 
2251 	addrconf_addr_solict_mult(addr, &maddr);
2252 	__ipv6_dev_mc_dec(idev, &maddr);
2253 }
2254 
2255 /* caller must hold RTNL */
addrconf_join_anycast(struct inet6_ifaddr * ifp)2256 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
2257 {
2258 	struct in6_addr addr;
2259 
2260 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2261 		return;
2262 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2263 	if (ipv6_addr_any(&addr))
2264 		return;
2265 	__ipv6_dev_ac_inc(ifp->idev, &addr);
2266 }
2267 
2268 /* caller must hold RTNL */
addrconf_leave_anycast(struct inet6_ifaddr * ifp)2269 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
2270 {
2271 	struct in6_addr addr;
2272 
2273 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2274 		return;
2275 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2276 	if (ipv6_addr_any(&addr))
2277 		return;
2278 	__ipv6_dev_ac_dec(ifp->idev, &addr);
2279 }
2280 
addrconf_ifid_6lowpan(u8 * eui,struct net_device * dev)2281 static int addrconf_ifid_6lowpan(u8 *eui, struct net_device *dev)
2282 {
2283 	switch (dev->addr_len) {
2284 	case ETH_ALEN:
2285 		memcpy(eui, dev->dev_addr, 3);
2286 		eui[3] = 0xFF;
2287 		eui[4] = 0xFE;
2288 		memcpy(eui + 5, dev->dev_addr + 3, 3);
2289 		break;
2290 	case EUI64_ADDR_LEN:
2291 		memcpy(eui, dev->dev_addr, EUI64_ADDR_LEN);
2292 		eui[0] ^= 2;
2293 		break;
2294 	default:
2295 		return -1;
2296 	}
2297 
2298 	return 0;
2299 }
2300 
addrconf_ifid_ieee1394(u8 * eui,struct net_device * dev)2301 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
2302 {
2303 	const union fwnet_hwaddr *ha;
2304 
2305 	if (dev->addr_len != FWNET_ALEN)
2306 		return -1;
2307 
2308 	ha = (const union fwnet_hwaddr *)dev->dev_addr;
2309 
2310 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
2311 	eui[0] ^= 2;
2312 	return 0;
2313 }
2314 
addrconf_ifid_arcnet(u8 * eui,struct net_device * dev)2315 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
2316 {
2317 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
2318 	if (dev->addr_len != ARCNET_ALEN)
2319 		return -1;
2320 	memset(eui, 0, 7);
2321 	eui[7] = *(u8 *)dev->dev_addr;
2322 	return 0;
2323 }
2324 
addrconf_ifid_infiniband(u8 * eui,struct net_device * dev)2325 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
2326 {
2327 	if (dev->addr_len != INFINIBAND_ALEN)
2328 		return -1;
2329 	memcpy(eui, dev->dev_addr + 12, 8);
2330 	eui[0] |= 2;
2331 	return 0;
2332 }
2333 
__ipv6_isatap_ifid(u8 * eui,__be32 addr)2334 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
2335 {
2336 	if (addr == 0)
2337 		return -1;
2338 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
2339 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
2340 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
2341 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
2342 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
2343 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
2344 	eui[1] = 0;
2345 	eui[2] = 0x5E;
2346 	eui[3] = 0xFE;
2347 	memcpy(eui + 4, &addr, 4);
2348 	return 0;
2349 }
2350 
addrconf_ifid_sit(u8 * eui,struct net_device * dev)2351 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
2352 {
2353 	if (dev->priv_flags & IFF_ISATAP)
2354 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2355 	return -1;
2356 }
2357 
addrconf_ifid_gre(u8 * eui,struct net_device * dev)2358 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
2359 {
2360 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2361 }
2362 
addrconf_ifid_ip6tnl(u8 * eui,struct net_device * dev)2363 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
2364 {
2365 	memcpy(eui, dev->perm_addr, 3);
2366 	memcpy(eui + 5, dev->perm_addr + 3, 3);
2367 	eui[3] = 0xFF;
2368 	eui[4] = 0xFE;
2369 	eui[0] ^= 2;
2370 	return 0;
2371 }
2372 
ipv6_generate_eui64(u8 * eui,struct net_device * dev)2373 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
2374 {
2375 	switch (dev->type) {
2376 	case ARPHRD_ETHER:
2377 	case ARPHRD_FDDI:
2378 		return addrconf_ifid_eui48(eui, dev);
2379 	case ARPHRD_ARCNET:
2380 		return addrconf_ifid_arcnet(eui, dev);
2381 	case ARPHRD_INFINIBAND:
2382 		return addrconf_ifid_infiniband(eui, dev);
2383 	case ARPHRD_SIT:
2384 		return addrconf_ifid_sit(eui, dev);
2385 	case ARPHRD_IPGRE:
2386 	case ARPHRD_TUNNEL:
2387 		return addrconf_ifid_gre(eui, dev);
2388 	case ARPHRD_6LOWPAN:
2389 		return addrconf_ifid_6lowpan(eui, dev);
2390 	case ARPHRD_IEEE1394:
2391 		return addrconf_ifid_ieee1394(eui, dev);
2392 	case ARPHRD_TUNNEL6:
2393 	case ARPHRD_IP6GRE:
2394 	case ARPHRD_RAWIP:
2395 		return addrconf_ifid_ip6tnl(eui, dev);
2396 	}
2397 	return -1;
2398 }
2399 
ipv6_inherit_eui64(u8 * eui,struct inet6_dev * idev)2400 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
2401 {
2402 	int err = -1;
2403 	struct inet6_ifaddr *ifp;
2404 
2405 	read_lock_bh(&idev->lock);
2406 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
2407 		if (ifp->scope > IFA_LINK)
2408 			break;
2409 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
2410 			memcpy(eui, ifp->addr.s6_addr+8, 8);
2411 			err = 0;
2412 			break;
2413 		}
2414 	}
2415 	read_unlock_bh(&idev->lock);
2416 	return err;
2417 }
2418 
2419 /* Generation of a randomized Interface Identifier
2420  * draft-ietf-6man-rfc4941bis, Section 3.3.1
2421  */
2422 
ipv6_gen_rnd_iid(struct in6_addr * addr)2423 static void ipv6_gen_rnd_iid(struct in6_addr *addr)
2424 {
2425 regen:
2426 	get_random_bytes(&addr->s6_addr[8], 8);
2427 
2428 	/* <draft-ietf-6man-rfc4941bis-08.txt>, Section 3.3.1:
2429 	 * check if generated address is not inappropriate:
2430 	 *
2431 	 * - Reserved IPv6 Interface Identifiers
2432 	 * - XXX: already assigned to an address on the device
2433 	 */
2434 
2435 	/* Subnet-router anycast: 0000:0000:0000:0000 */
2436 	if (!(addr->s6_addr32[2] | addr->s6_addr32[3]))
2437 		goto regen;
2438 
2439 	/* IANA Ethernet block: 0200:5EFF:FE00:0000-0200:5EFF:FE00:5212
2440 	 * Proxy Mobile IPv6:   0200:5EFF:FE00:5213
2441 	 * IANA Ethernet block: 0200:5EFF:FE00:5214-0200:5EFF:FEFF:FFFF
2442 	 */
2443 	if (ntohl(addr->s6_addr32[2]) == 0x02005eff &&
2444 	    (ntohl(addr->s6_addr32[3]) & 0Xff000000) == 0xfe000000)
2445 		goto regen;
2446 
2447 	/* Reserved subnet anycast addresses */
2448 	if (ntohl(addr->s6_addr32[2]) == 0xfdffffff &&
2449 	    ntohl(addr->s6_addr32[3]) >= 0Xffffff80)
2450 		goto regen;
2451 }
2452 
2453 /*
2454  *	Add prefix route.
2455  */
2456 
2457 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)2458 addrconf_prefix_route(struct in6_addr *pfx, int plen, u32 metric,
2459 		      struct net_device *dev, unsigned long expires,
2460 		      u32 flags, gfp_t gfp_flags)
2461 {
2462 	struct fib6_config cfg = {
2463 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX,
2464 		.fc_metric = metric ? : IP6_RT_PRIO_ADDRCONF,
2465 		.fc_ifindex = dev->ifindex,
2466 		.fc_expires = expires,
2467 		.fc_dst_len = plen,
2468 		.fc_flags = RTF_UP | flags,
2469 		.fc_nlinfo.nl_net = dev_net(dev),
2470 		.fc_protocol = RTPROT_KERNEL,
2471 		.fc_type = RTN_UNICAST,
2472 	};
2473 
2474 	cfg.fc_dst = *pfx;
2475 
2476 	/* Prevent useless cloning on PtP SIT.
2477 	   This thing is done here expecting that the whole
2478 	   class of non-broadcast devices need not cloning.
2479 	 */
2480 #if IS_ENABLED(CONFIG_IPV6_SIT)
2481 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2482 		cfg.fc_flags |= RTF_NONEXTHOP;
2483 #endif
2484 
2485 	ip6_route_add(&cfg, gfp_flags, NULL);
2486 }
2487 
2488 
addrconf_get_prefix_route(const struct in6_addr * pfx,int plen,const struct net_device * dev,u32 flags,u32 noflags,bool no_gw)2489 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2490 						  int plen,
2491 						  const struct net_device *dev,
2492 						  u32 flags, u32 noflags,
2493 						  bool no_gw)
2494 {
2495 	struct fib6_node *fn;
2496 	struct fib6_info *rt = NULL;
2497 	struct fib6_table *table;
2498 	u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX;
2499 
2500 	table = fib6_get_table(dev_net(dev), tb_id);
2501 	if (!table)
2502 		return NULL;
2503 
2504 	rcu_read_lock();
2505 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0, true);
2506 	if (!fn)
2507 		goto out;
2508 
2509 	for_each_fib6_node_rt_rcu(fn) {
2510 		/* prefix routes only use builtin fib6_nh */
2511 		if (rt->nh)
2512 			continue;
2513 
2514 		if (rt->fib6_nh->fib_nh_dev->ifindex != dev->ifindex)
2515 			continue;
2516 		if (no_gw && rt->fib6_nh->fib_nh_gw_family)
2517 			continue;
2518 		if ((rt->fib6_flags & flags) != flags)
2519 			continue;
2520 		if ((rt->fib6_flags & noflags) != 0)
2521 			continue;
2522 		if (!fib6_info_hold_safe(rt))
2523 			continue;
2524 		break;
2525 	}
2526 out:
2527 	rcu_read_unlock();
2528 	return rt;
2529 }
2530 
2531 
2532 /* Create "default" multicast route to the interface */
2533 
addrconf_add_mroute(struct net_device * dev)2534 static void addrconf_add_mroute(struct net_device *dev)
2535 {
2536 	struct fib6_config cfg = {
2537 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_LOCAL,
2538 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2539 		.fc_ifindex = dev->ifindex,
2540 		.fc_dst_len = 8,
2541 		.fc_flags = RTF_UP,
2542 		.fc_type = RTN_MULTICAST,
2543 		.fc_nlinfo.nl_net = dev_net(dev),
2544 		.fc_protocol = RTPROT_KERNEL,
2545 	};
2546 
2547 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2548 
2549 	ip6_route_add(&cfg, GFP_KERNEL, NULL);
2550 }
2551 
addrconf_add_dev(struct net_device * dev)2552 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2553 {
2554 	struct inet6_dev *idev;
2555 
2556 	ASSERT_RTNL();
2557 
2558 	idev = ipv6_find_idev(dev);
2559 	if (IS_ERR(idev))
2560 		return idev;
2561 
2562 	if (idev->cnf.disable_ipv6)
2563 		return ERR_PTR(-EACCES);
2564 
2565 	/* Add default multicast route */
2566 	if (!(dev->flags & IFF_LOOPBACK) && !netif_is_l3_master(dev))
2567 		addrconf_add_mroute(dev);
2568 
2569 	return idev;
2570 }
2571 
delete_tempaddrs(struct inet6_dev * idev,struct inet6_ifaddr * ifp)2572 static void delete_tempaddrs(struct inet6_dev *idev,
2573 			     struct inet6_ifaddr *ifp)
2574 {
2575 	struct inet6_ifaddr *ift, *tmp;
2576 
2577 	write_lock_bh(&idev->lock);
2578 	list_for_each_entry_safe(ift, tmp, &idev->tempaddr_list, tmp_list) {
2579 		if (ift->ifpub != ifp)
2580 			continue;
2581 
2582 		in6_ifa_hold(ift);
2583 		write_unlock_bh(&idev->lock);
2584 		ipv6_del_addr(ift);
2585 		write_lock_bh(&idev->lock);
2586 	}
2587 	write_unlock_bh(&idev->lock);
2588 }
2589 
manage_tempaddrs(struct inet6_dev * idev,struct inet6_ifaddr * ifp,__u32 valid_lft,__u32 prefered_lft,bool create,unsigned long now)2590 static void manage_tempaddrs(struct inet6_dev *idev,
2591 			     struct inet6_ifaddr *ifp,
2592 			     __u32 valid_lft, __u32 prefered_lft,
2593 			     bool create, unsigned long now)
2594 {
2595 	u32 flags;
2596 	struct inet6_ifaddr *ift;
2597 
2598 	read_lock_bh(&idev->lock);
2599 	/* update all temporary addresses in the list */
2600 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2601 		int age, max_valid, max_prefered;
2602 
2603 		if (ifp != ift->ifpub)
2604 			continue;
2605 
2606 		/* RFC 4941 section 3.3:
2607 		 * If a received option will extend the lifetime of a public
2608 		 * address, the lifetimes of temporary addresses should
2609 		 * be extended, subject to the overall constraint that no
2610 		 * temporary addresses should ever remain "valid" or "preferred"
2611 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2612 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2613 		 */
2614 		age = (now - ift->cstamp) / HZ;
2615 		max_valid = READ_ONCE(idev->cnf.temp_valid_lft) - age;
2616 		if (max_valid < 0)
2617 			max_valid = 0;
2618 
2619 		max_prefered = READ_ONCE(idev->cnf.temp_prefered_lft) -
2620 			       idev->desync_factor - age;
2621 		if (max_prefered < 0)
2622 			max_prefered = 0;
2623 
2624 		if (valid_lft > max_valid)
2625 			valid_lft = max_valid;
2626 
2627 		if (prefered_lft > max_prefered)
2628 			prefered_lft = max_prefered;
2629 
2630 		spin_lock(&ift->lock);
2631 		flags = ift->flags;
2632 		ift->valid_lft = valid_lft;
2633 		ift->prefered_lft = prefered_lft;
2634 		ift->tstamp = now;
2635 		if (prefered_lft > 0)
2636 			ift->flags &= ~IFA_F_DEPRECATED;
2637 
2638 		spin_unlock(&ift->lock);
2639 		if (!(flags&IFA_F_TENTATIVE))
2640 			ipv6_ifa_notify(0, ift);
2641 	}
2642 
2643 	/* Also create a temporary address if it's enabled but no temporary
2644 	 * address currently exists.
2645 	 * However, we get called with valid_lft == 0, prefered_lft == 0, create == false
2646 	 * as part of cleanup (ie. deleting the mngtmpaddr).
2647 	 * We don't want that to result in creating a new temporary ip address.
2648 	 */
2649 	if (list_empty(&idev->tempaddr_list) && (valid_lft || prefered_lft))
2650 		create = true;
2651 
2652 	if (create && READ_ONCE(idev->cnf.use_tempaddr) > 0) {
2653 		/* When a new public address is created as described
2654 		 * in [ADDRCONF], also create a new temporary address.
2655 		 */
2656 		read_unlock_bh(&idev->lock);
2657 		ipv6_create_tempaddr(ifp, false);
2658 	} else {
2659 		read_unlock_bh(&idev->lock);
2660 	}
2661 }
2662 
is_addr_mode_generate_stable(struct inet6_dev * idev)2663 static bool is_addr_mode_generate_stable(struct inet6_dev *idev)
2664 {
2665 	return idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY ||
2666 	       idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_RANDOM;
2667 }
2668 
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)2669 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
2670 				 const struct prefix_info *pinfo,
2671 				 struct inet6_dev *in6_dev,
2672 				 const struct in6_addr *addr, int addr_type,
2673 				 u32 addr_flags, bool sllao, bool tokenized,
2674 				 __u32 valid_lft, u32 prefered_lft)
2675 {
2676 	struct inet6_ifaddr *ifp = ipv6_get_ifaddr(net, addr, dev, 1);
2677 	int create = 0, update_lft = 0;
2678 
2679 	if (!ifp && valid_lft) {
2680 		int max_addresses = READ_ONCE(in6_dev->cnf.max_addresses);
2681 		struct ifa6_config cfg = {
2682 			.pfx = addr,
2683 			.plen = pinfo->prefix_len,
2684 			.ifa_flags = addr_flags,
2685 			.valid_lft = valid_lft,
2686 			.preferred_lft = prefered_lft,
2687 			.scope = addr_type & IPV6_ADDR_SCOPE_MASK,
2688 			.ifa_proto = IFAPROT_KERNEL_RA
2689 		};
2690 
2691 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2692 		if ((READ_ONCE(net->ipv6.devconf_all->optimistic_dad) ||
2693 		     READ_ONCE(in6_dev->cnf.optimistic_dad)) &&
2694 		    !net->ipv6.devconf_all->forwarding && sllao)
2695 			cfg.ifa_flags |= IFA_F_OPTIMISTIC;
2696 #endif
2697 
2698 		/* Do not allow to create too much of autoconfigured
2699 		 * addresses; this would be too easy way to crash kernel.
2700 		 */
2701 		if (!max_addresses ||
2702 		    ipv6_count_addresses(in6_dev) < max_addresses)
2703 			ifp = ipv6_add_addr(in6_dev, &cfg, false, NULL);
2704 
2705 		if (IS_ERR_OR_NULL(ifp))
2706 			return -1;
2707 
2708 		create = 1;
2709 		spin_lock_bh(&ifp->lock);
2710 		ifp->flags |= IFA_F_MANAGETEMPADDR;
2711 		ifp->cstamp = jiffies;
2712 		ifp->tokenized = tokenized;
2713 		spin_unlock_bh(&ifp->lock);
2714 		addrconf_dad_start(ifp);
2715 	}
2716 
2717 	if (ifp) {
2718 		u32 flags;
2719 		unsigned long now;
2720 		u32 stored_lft;
2721 
2722 		/* update lifetime (RFC2462 5.5.3 e) */
2723 		spin_lock_bh(&ifp->lock);
2724 		now = jiffies;
2725 		if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2726 			stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2727 		else
2728 			stored_lft = 0;
2729 
2730 		/* RFC4862 Section 5.5.3e:
2731 		 * "Note that the preferred lifetime of the
2732 		 *  corresponding address is always reset to
2733 		 *  the Preferred Lifetime in the received
2734 		 *  Prefix Information option, regardless of
2735 		 *  whether the valid lifetime is also reset or
2736 		 *  ignored."
2737 		 *
2738 		 * So we should always update prefered_lft here.
2739 		 */
2740 		update_lft = !create && stored_lft;
2741 
2742 		if (update_lft && !READ_ONCE(in6_dev->cnf.ra_honor_pio_life)) {
2743 			const u32 minimum_lft = min_t(u32,
2744 				stored_lft, MIN_VALID_LIFETIME);
2745 			valid_lft = max(valid_lft, minimum_lft);
2746 		}
2747 
2748 		if (update_lft) {
2749 			ifp->valid_lft = valid_lft;
2750 			ifp->prefered_lft = prefered_lft;
2751 			WRITE_ONCE(ifp->tstamp, now);
2752 			flags = ifp->flags;
2753 			ifp->flags &= ~IFA_F_DEPRECATED;
2754 			spin_unlock_bh(&ifp->lock);
2755 
2756 			if (!(flags&IFA_F_TENTATIVE))
2757 				ipv6_ifa_notify(0, ifp);
2758 		} else
2759 			spin_unlock_bh(&ifp->lock);
2760 
2761 		manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2762 				 create, now);
2763 
2764 		in6_ifa_put(ifp);
2765 		addrconf_verify(net);
2766 	}
2767 
2768 	return 0;
2769 }
2770 EXPORT_SYMBOL_GPL(addrconf_prefix_rcv_add_addr);
2771 
addrconf_prefix_rcv(struct net_device * dev,u8 * opt,int len,bool sllao)2772 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2773 {
2774 	struct prefix_info *pinfo;
2775 	struct fib6_table *table;
2776 	__u32 valid_lft;
2777 	__u32 prefered_lft;
2778 	int addr_type, err;
2779 	u32 addr_flags = 0;
2780 	struct inet6_dev *in6_dev;
2781 	struct net *net = dev_net(dev);
2782 	bool ignore_autoconf = false;
2783 
2784 	pinfo = (struct prefix_info *) opt;
2785 
2786 	if (len < sizeof(struct prefix_info)) {
2787 		netdev_dbg(dev, "addrconf: prefix option too short\n");
2788 		return;
2789 	}
2790 
2791 	/*
2792 	 *	Validation checks ([ADDRCONF], page 19)
2793 	 */
2794 
2795 	addr_type = ipv6_addr_type(&pinfo->prefix);
2796 
2797 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2798 		return;
2799 
2800 	valid_lft = ntohl(pinfo->valid);
2801 	prefered_lft = ntohl(pinfo->prefered);
2802 
2803 	if (prefered_lft > valid_lft) {
2804 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2805 		return;
2806 	}
2807 
2808 	in6_dev = in6_dev_get(dev);
2809 
2810 	if (!in6_dev) {
2811 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2812 				    dev->name);
2813 		return;
2814 	}
2815 
2816 	if (valid_lft != 0 && valid_lft < in6_dev->cnf.accept_ra_min_lft)
2817 		goto put;
2818 
2819 	/*
2820 	 *	Two things going on here:
2821 	 *	1) Add routes for on-link prefixes
2822 	 *	2) Configure prefixes with the auto flag set
2823 	 */
2824 
2825 	if (pinfo->onlink) {
2826 		struct fib6_info *rt;
2827 		unsigned long rt_expires;
2828 
2829 		/* Avoid arithmetic overflow. Really, we could
2830 		 * save rt_expires in seconds, likely valid_lft,
2831 		 * but it would require division in fib gc, that it
2832 		 * not good.
2833 		 */
2834 		if (HZ > USER_HZ)
2835 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2836 		else
2837 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2838 
2839 		if (addrconf_finite_timeout(rt_expires))
2840 			rt_expires *= HZ;
2841 
2842 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2843 					       pinfo->prefix_len,
2844 					       dev,
2845 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2846 					       RTF_DEFAULT, true);
2847 
2848 		if (rt) {
2849 			/* Autoconf prefix route */
2850 			if (valid_lft == 0) {
2851 				ip6_del_rt(net, rt, false);
2852 				rt = NULL;
2853 			} else {
2854 				table = rt->fib6_table;
2855 				spin_lock_bh(&table->tb6_lock);
2856 
2857 				if (addrconf_finite_timeout(rt_expires)) {
2858 					/* not infinity */
2859 					fib6_set_expires(rt, jiffies + rt_expires);
2860 					fib6_add_gc_list(rt);
2861 				} else {
2862 					fib6_clean_expires(rt);
2863 					fib6_remove_gc_list(rt);
2864 				}
2865 
2866 				spin_unlock_bh(&table->tb6_lock);
2867 			}
2868 		} else if (valid_lft) {
2869 			clock_t expires = 0;
2870 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2871 			if (addrconf_finite_timeout(rt_expires)) {
2872 				/* not infinity */
2873 				flags |= RTF_EXPIRES;
2874 				expires = jiffies_to_clock_t(rt_expires);
2875 			}
2876 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2877 					      0, dev, expires, flags,
2878 					      GFP_ATOMIC);
2879 		}
2880 		fib6_info_release(rt);
2881 	}
2882 
2883 	/* Try to figure out our local address for this prefix */
2884 
2885 	ignore_autoconf = READ_ONCE(in6_dev->cnf.ra_honor_pio_pflag) && pinfo->preferpd;
2886 	if (pinfo->autoconf && in6_dev->cnf.autoconf && !ignore_autoconf) {
2887 		struct in6_addr addr;
2888 		bool tokenized = false, dev_addr_generated = false;
2889 
2890 		if (pinfo->prefix_len == 64) {
2891 			memcpy(&addr, &pinfo->prefix, 8);
2892 
2893 			if (!ipv6_addr_any(&in6_dev->token)) {
2894 				read_lock_bh(&in6_dev->lock);
2895 				memcpy(addr.s6_addr + 8,
2896 				       in6_dev->token.s6_addr + 8, 8);
2897 				read_unlock_bh(&in6_dev->lock);
2898 				tokenized = true;
2899 			} else if (is_addr_mode_generate_stable(in6_dev) &&
2900 				   !ipv6_generate_stable_address(&addr, 0,
2901 								 in6_dev)) {
2902 				addr_flags |= IFA_F_STABLE_PRIVACY;
2903 				goto ok;
2904 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2905 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2906 				goto put;
2907 			} else {
2908 				dev_addr_generated = true;
2909 			}
2910 			goto ok;
2911 		}
2912 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2913 				    pinfo->prefix_len);
2914 		goto put;
2915 
2916 ok:
2917 		err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
2918 						   &addr, addr_type,
2919 						   addr_flags, sllao,
2920 						   tokenized, valid_lft,
2921 						   prefered_lft);
2922 		if (err)
2923 			goto put;
2924 
2925 		/* Ignore error case here because previous prefix add addr was
2926 		 * successful which will be notified.
2927 		 */
2928 		ndisc_ops_prefix_rcv_add_addr(net, dev, pinfo, in6_dev, &addr,
2929 					      addr_type, addr_flags, sllao,
2930 					      tokenized, valid_lft,
2931 					      prefered_lft,
2932 					      dev_addr_generated);
2933 	}
2934 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2935 put:
2936 	in6_dev_put(in6_dev);
2937 }
2938 
addrconf_set_sit_dstaddr(struct net * net,struct net_device * dev,struct in6_ifreq * ireq)2939 static int addrconf_set_sit_dstaddr(struct net *net, struct net_device *dev,
2940 		struct in6_ifreq *ireq)
2941 {
2942 	struct ip_tunnel_parm_kern p = { };
2943 	int err;
2944 
2945 	if (!(ipv6_addr_type(&ireq->ifr6_addr) & IPV6_ADDR_COMPATv4))
2946 		return -EADDRNOTAVAIL;
2947 
2948 	p.iph.daddr = ireq->ifr6_addr.s6_addr32[3];
2949 	p.iph.version = 4;
2950 	p.iph.ihl = 5;
2951 	p.iph.protocol = IPPROTO_IPV6;
2952 	p.iph.ttl = 64;
2953 
2954 	if (!dev->netdev_ops->ndo_tunnel_ctl)
2955 		return -EOPNOTSUPP;
2956 	err = dev->netdev_ops->ndo_tunnel_ctl(dev, &p, SIOCADDTUNNEL);
2957 	if (err)
2958 		return err;
2959 
2960 	dev = __dev_get_by_name(net, p.name);
2961 	if (!dev)
2962 		return -ENOBUFS;
2963 	return dev_open(dev, NULL);
2964 }
2965 
2966 /*
2967  *	Set destination address.
2968  *	Special case for SIT interfaces where we create a new "virtual"
2969  *	device.
2970  */
addrconf_set_dstaddr(struct net * net,void __user * arg)2971 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2972 {
2973 	struct net_device *dev;
2974 	struct in6_ifreq ireq;
2975 	int err = -ENODEV;
2976 
2977 	if (!IS_ENABLED(CONFIG_IPV6_SIT))
2978 		return -ENODEV;
2979 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2980 		return -EFAULT;
2981 
2982 	rtnl_net_lock(net);
2983 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2984 	if (dev && dev->type == ARPHRD_SIT)
2985 		err = addrconf_set_sit_dstaddr(net, dev, &ireq);
2986 	rtnl_net_unlock(net);
2987 	return err;
2988 }
2989 
ipv6_mc_config(struct sock * sk,bool join,const struct in6_addr * addr,int ifindex)2990 static int ipv6_mc_config(struct sock *sk, bool join,
2991 			  const struct in6_addr *addr, int ifindex)
2992 {
2993 	int ret;
2994 
2995 	ASSERT_RTNL();
2996 
2997 	lock_sock(sk);
2998 	if (join)
2999 		ret = ipv6_sock_mc_join(sk, ifindex, addr);
3000 	else
3001 		ret = ipv6_sock_mc_drop(sk, ifindex, addr);
3002 	release_sock(sk);
3003 
3004 	return ret;
3005 }
3006 
3007 /*
3008  *	Manual configuration of address on an interface
3009  */
inet6_addr_add(struct net * net,struct net_device * dev,struct ifa6_config * cfg,clock_t expires,u32 flags,struct netlink_ext_ack * extack)3010 static int inet6_addr_add(struct net *net, struct net_device *dev,
3011 			  struct ifa6_config *cfg, clock_t expires, u32 flags,
3012 			  struct netlink_ext_ack *extack)
3013 {
3014 	struct inet6_ifaddr *ifp;
3015 	struct inet6_dev *idev;
3016 
3017 	ASSERT_RTNL_NET(net);
3018 
3019 	if (cfg->plen > 128) {
3020 		NL_SET_ERR_MSG_MOD(extack, "Invalid prefix length");
3021 		return -EINVAL;
3022 	}
3023 
3024 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR && cfg->plen != 64) {
3025 		NL_SET_ERR_MSG_MOD(extack, "address with \"mngtmpaddr\" flag must have a prefix length of 64");
3026 		return -EINVAL;
3027 	}
3028 
3029 	idev = addrconf_add_dev(dev);
3030 	if (IS_ERR(idev)) {
3031 		NL_SET_ERR_MSG_MOD(extack, "IPv6 is disabled on this device");
3032 		return PTR_ERR(idev);
3033 	}
3034 
3035 	if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
3036 		int ret = ipv6_mc_config(net->ipv6.mc_autojoin_sk,
3037 					 true, cfg->pfx, dev->ifindex);
3038 
3039 		if (ret < 0) {
3040 			NL_SET_ERR_MSG_MOD(extack, "Multicast auto join failed");
3041 			return ret;
3042 		}
3043 	}
3044 
3045 	cfg->scope = ipv6_addr_scope(cfg->pfx);
3046 
3047 	ifp = ipv6_add_addr(idev, cfg, true, extack);
3048 	if (!IS_ERR(ifp)) {
3049 		if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
3050 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3051 					      ifp->rt_priority, dev, expires,
3052 					      flags, GFP_KERNEL);
3053 		}
3054 
3055 		/* Send a netlink notification if DAD is enabled and
3056 		 * optimistic flag is not set
3057 		 */
3058 		if (!(ifp->flags & (IFA_F_OPTIMISTIC | IFA_F_NODAD)))
3059 			ipv6_ifa_notify(0, ifp);
3060 		/*
3061 		 * Note that section 3.1 of RFC 4429 indicates
3062 		 * that the Optimistic flag should not be set for
3063 		 * manually configured addresses
3064 		 */
3065 		addrconf_dad_start(ifp);
3066 		if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR)
3067 			manage_tempaddrs(idev, ifp, cfg->valid_lft,
3068 					 cfg->preferred_lft, true, jiffies);
3069 		in6_ifa_put(ifp);
3070 		addrconf_verify_rtnl(net);
3071 		return 0;
3072 	} else if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
3073 		ipv6_mc_config(net->ipv6.mc_autojoin_sk, false,
3074 			       cfg->pfx, dev->ifindex);
3075 	}
3076 
3077 	return PTR_ERR(ifp);
3078 }
3079 
inet6_addr_del(struct net * net,int ifindex,u32 ifa_flags,const struct in6_addr * pfx,unsigned int plen,struct netlink_ext_ack * extack)3080 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
3081 			  const struct in6_addr *pfx, unsigned int plen,
3082 			  struct netlink_ext_ack *extack)
3083 {
3084 	struct inet6_ifaddr *ifp;
3085 	struct inet6_dev *idev;
3086 	struct net_device *dev;
3087 
3088 	if (plen > 128) {
3089 		NL_SET_ERR_MSG_MOD(extack, "Invalid prefix length");
3090 		return -EINVAL;
3091 	}
3092 
3093 	dev = __dev_get_by_index(net, ifindex);
3094 	if (!dev) {
3095 		NL_SET_ERR_MSG_MOD(extack, "Unable to find the interface");
3096 		return -ENODEV;
3097 	}
3098 
3099 	idev = __in6_dev_get_rtnl_net(dev);
3100 	if (!idev) {
3101 		NL_SET_ERR_MSG_MOD(extack, "IPv6 is disabled on this device");
3102 		return -ENXIO;
3103 	}
3104 
3105 	read_lock_bh(&idev->lock);
3106 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
3107 		if (ifp->prefix_len == plen &&
3108 		    ipv6_addr_equal(pfx, &ifp->addr)) {
3109 			in6_ifa_hold(ifp);
3110 			read_unlock_bh(&idev->lock);
3111 
3112 			ipv6_del_addr(ifp);
3113 
3114 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
3115 			    (ifp->flags & IFA_F_MANAGETEMPADDR))
3116 				delete_tempaddrs(idev, ifp);
3117 
3118 			addrconf_verify_rtnl(net);
3119 			if (ipv6_addr_is_multicast(pfx)) {
3120 				ipv6_mc_config(net->ipv6.mc_autojoin_sk,
3121 					       false, pfx, dev->ifindex);
3122 			}
3123 			return 0;
3124 		}
3125 	}
3126 	read_unlock_bh(&idev->lock);
3127 
3128 	NL_SET_ERR_MSG_MOD(extack, "address not found");
3129 	return -EADDRNOTAVAIL;
3130 }
3131 
3132 
addrconf_add_ifaddr(struct net * net,void __user * arg)3133 int addrconf_add_ifaddr(struct net *net, void __user *arg)
3134 {
3135 	struct ifa6_config cfg = {
3136 		.ifa_flags = IFA_F_PERMANENT,
3137 		.preferred_lft = INFINITY_LIFE_TIME,
3138 		.valid_lft = INFINITY_LIFE_TIME,
3139 	};
3140 	struct net_device *dev;
3141 	struct in6_ifreq ireq;
3142 	int err;
3143 
3144 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3145 		return -EPERM;
3146 
3147 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3148 		return -EFAULT;
3149 
3150 	cfg.pfx = &ireq.ifr6_addr;
3151 	cfg.plen = ireq.ifr6_prefixlen;
3152 
3153 	rtnl_net_lock(net);
3154 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
3155 	if (dev)
3156 		err = inet6_addr_add(net, dev, &cfg, 0, 0, NULL);
3157 	else
3158 		err = -ENODEV;
3159 	rtnl_net_unlock(net);
3160 	return err;
3161 }
3162 
addrconf_del_ifaddr(struct net * net,void __user * arg)3163 int addrconf_del_ifaddr(struct net *net, void __user *arg)
3164 {
3165 	struct in6_ifreq ireq;
3166 	int err;
3167 
3168 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3169 		return -EPERM;
3170 
3171 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3172 		return -EFAULT;
3173 
3174 	rtnl_net_lock(net);
3175 	err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
3176 			     ireq.ifr6_prefixlen, NULL);
3177 	rtnl_net_unlock(net);
3178 	return err;
3179 }
3180 
add_addr(struct inet6_dev * idev,const struct in6_addr * addr,int plen,int scope,u8 proto)3181 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
3182 		     int plen, int scope, u8 proto)
3183 {
3184 	struct inet6_ifaddr *ifp;
3185 	struct ifa6_config cfg = {
3186 		.pfx = addr,
3187 		.plen = plen,
3188 		.ifa_flags = IFA_F_PERMANENT,
3189 		.valid_lft = INFINITY_LIFE_TIME,
3190 		.preferred_lft = INFINITY_LIFE_TIME,
3191 		.scope = scope,
3192 		.ifa_proto = proto
3193 	};
3194 
3195 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3196 	if (!IS_ERR(ifp)) {
3197 		spin_lock_bh(&ifp->lock);
3198 		ifp->flags &= ~IFA_F_TENTATIVE;
3199 		spin_unlock_bh(&ifp->lock);
3200 		rt_genid_bump_ipv6(dev_net(idev->dev));
3201 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3202 		in6_ifa_put(ifp);
3203 	}
3204 }
3205 
3206 #if IS_ENABLED(CONFIG_IPV6_SIT) || IS_ENABLED(CONFIG_NET_IPGRE) || IS_ENABLED(CONFIG_IPV6_GRE)
add_v4_addrs(struct inet6_dev * idev)3207 static void add_v4_addrs(struct inet6_dev *idev)
3208 {
3209 	struct in6_addr addr;
3210 	struct net_device *dev;
3211 	struct net *net = dev_net(idev->dev);
3212 	int scope, plen;
3213 	u32 pflags = 0;
3214 
3215 	ASSERT_RTNL();
3216 
3217 	memset(&addr, 0, sizeof(struct in6_addr));
3218 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
3219 
3220 	if (!(idev->dev->flags & IFF_POINTOPOINT) && idev->dev->type == ARPHRD_SIT) {
3221 		scope = IPV6_ADDR_COMPATv4;
3222 		plen = 96;
3223 		pflags |= RTF_NONEXTHOP;
3224 	} else {
3225 		if (idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_NONE)
3226 			return;
3227 
3228 		addr.s6_addr32[0] = htonl(0xfe800000);
3229 		scope = IFA_LINK;
3230 		plen = 64;
3231 	}
3232 
3233 	if (addr.s6_addr32[3]) {
3234 		add_addr(idev, &addr, plen, scope, IFAPROT_UNSPEC);
3235 		addrconf_prefix_route(&addr, plen, 0, idev->dev, 0, pflags,
3236 				      GFP_KERNEL);
3237 		return;
3238 	}
3239 
3240 	for_each_netdev(net, dev) {
3241 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
3242 		if (in_dev && (dev->flags & IFF_UP)) {
3243 			struct in_ifaddr *ifa;
3244 			int flag = scope;
3245 
3246 			in_dev_for_each_ifa_rtnl(ifa, in_dev) {
3247 				addr.s6_addr32[3] = ifa->ifa_local;
3248 
3249 				if (ifa->ifa_scope == RT_SCOPE_LINK)
3250 					continue;
3251 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
3252 					if (idev->dev->flags&IFF_POINTOPOINT)
3253 						continue;
3254 					flag |= IFA_HOST;
3255 				}
3256 
3257 				add_addr(idev, &addr, plen, flag,
3258 					 IFAPROT_UNSPEC);
3259 				addrconf_prefix_route(&addr, plen, 0, idev->dev,
3260 						      0, pflags, GFP_KERNEL);
3261 			}
3262 		}
3263 	}
3264 }
3265 #endif
3266 
init_loopback(struct net_device * dev)3267 static void init_loopback(struct net_device *dev)
3268 {
3269 	struct inet6_dev  *idev;
3270 
3271 	/* ::1 */
3272 
3273 	ASSERT_RTNL();
3274 
3275 	idev = ipv6_find_idev(dev);
3276 	if (IS_ERR(idev)) {
3277 		pr_debug("%s: add_dev failed\n", __func__);
3278 		return;
3279 	}
3280 
3281 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST, IFAPROT_KERNEL_LO);
3282 }
3283 
addrconf_add_linklocal(struct inet6_dev * idev,const struct in6_addr * addr,u32 flags)3284 void addrconf_add_linklocal(struct inet6_dev *idev,
3285 			    const struct in6_addr *addr, u32 flags)
3286 {
3287 	struct ifa6_config cfg = {
3288 		.pfx = addr,
3289 		.plen = 64,
3290 		.ifa_flags = flags | IFA_F_PERMANENT,
3291 		.valid_lft = INFINITY_LIFE_TIME,
3292 		.preferred_lft = INFINITY_LIFE_TIME,
3293 		.scope = IFA_LINK,
3294 		.ifa_proto = IFAPROT_KERNEL_LL
3295 	};
3296 	struct inet6_ifaddr *ifp;
3297 
3298 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
3299 	if ((READ_ONCE(dev_net(idev->dev)->ipv6.devconf_all->optimistic_dad) ||
3300 	     READ_ONCE(idev->cnf.optimistic_dad)) &&
3301 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
3302 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
3303 #endif
3304 
3305 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3306 	if (!IS_ERR(ifp)) {
3307 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, 0, idev->dev,
3308 				      0, 0, GFP_ATOMIC);
3309 		addrconf_dad_start(ifp);
3310 		in6_ifa_put(ifp);
3311 	}
3312 }
3313 EXPORT_SYMBOL_GPL(addrconf_add_linklocal);
3314 
ipv6_reserved_interfaceid(struct in6_addr address)3315 static bool ipv6_reserved_interfaceid(struct in6_addr address)
3316 {
3317 	if ((address.s6_addr32[2] | address.s6_addr32[3]) == 0)
3318 		return true;
3319 
3320 	if (address.s6_addr32[2] == htonl(0x02005eff) &&
3321 	    ((address.s6_addr32[3] & htonl(0xfe000000)) == htonl(0xfe000000)))
3322 		return true;
3323 
3324 	if (address.s6_addr32[2] == htonl(0xfdffffff) &&
3325 	    ((address.s6_addr32[3] & htonl(0xffffff80)) == htonl(0xffffff80)))
3326 		return true;
3327 
3328 	return false;
3329 }
3330 
ipv6_generate_stable_address(struct in6_addr * address,u8 dad_count,const struct inet6_dev * idev)3331 static int ipv6_generate_stable_address(struct in6_addr *address,
3332 					u8 dad_count,
3333 					const struct inet6_dev *idev)
3334 {
3335 	static DEFINE_SPINLOCK(lock);
3336 	static __u32 digest[SHA1_DIGEST_WORDS];
3337 	static __u32 workspace[SHA1_WORKSPACE_WORDS];
3338 
3339 	static union {
3340 		char __data[SHA1_BLOCK_SIZE];
3341 		struct {
3342 			struct in6_addr secret;
3343 			__be32 prefix[2];
3344 			unsigned char hwaddr[MAX_ADDR_LEN];
3345 			u8 dad_count;
3346 		} __packed;
3347 	} data;
3348 
3349 	struct in6_addr secret;
3350 	struct in6_addr temp;
3351 	struct net *net = dev_net(idev->dev);
3352 
3353 	BUILD_BUG_ON(sizeof(data.__data) != sizeof(data));
3354 
3355 	if (idev->cnf.stable_secret.initialized)
3356 		secret = idev->cnf.stable_secret.secret;
3357 	else if (net->ipv6.devconf_dflt->stable_secret.initialized)
3358 		secret = net->ipv6.devconf_dflt->stable_secret.secret;
3359 	else
3360 		return -1;
3361 
3362 retry:
3363 	spin_lock_bh(&lock);
3364 
3365 	sha1_init(digest);
3366 	memset(&data, 0, sizeof(data));
3367 	memset(workspace, 0, sizeof(workspace));
3368 	memcpy(data.hwaddr, idev->dev->perm_addr, idev->dev->addr_len);
3369 	data.prefix[0] = address->s6_addr32[0];
3370 	data.prefix[1] = address->s6_addr32[1];
3371 	data.secret = secret;
3372 	data.dad_count = dad_count;
3373 
3374 	sha1_transform(digest, data.__data, workspace);
3375 
3376 	temp = *address;
3377 	temp.s6_addr32[2] = (__force __be32)digest[0];
3378 	temp.s6_addr32[3] = (__force __be32)digest[1];
3379 
3380 	spin_unlock_bh(&lock);
3381 
3382 	if (ipv6_reserved_interfaceid(temp)) {
3383 		dad_count++;
3384 		if (dad_count > dev_net(idev->dev)->ipv6.sysctl.idgen_retries)
3385 			return -1;
3386 		goto retry;
3387 	}
3388 
3389 	*address = temp;
3390 	return 0;
3391 }
3392 
ipv6_gen_mode_random_init(struct inet6_dev * idev)3393 static void ipv6_gen_mode_random_init(struct inet6_dev *idev)
3394 {
3395 	struct ipv6_stable_secret *s = &idev->cnf.stable_secret;
3396 
3397 	if (s->initialized)
3398 		return;
3399 	s = &idev->cnf.stable_secret;
3400 	get_random_bytes(&s->secret, sizeof(s->secret));
3401 	s->initialized = true;
3402 }
3403 
addrconf_addr_gen(struct inet6_dev * idev,bool prefix_route)3404 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
3405 {
3406 	struct in6_addr addr;
3407 
3408 	/* no link local addresses on L3 master devices */
3409 	if (netif_is_l3_master(idev->dev))
3410 		return;
3411 
3412 	/* no link local addresses on devices flagged as slaves */
3413 	if (idev->dev->priv_flags & IFF_NO_ADDRCONF)
3414 		return;
3415 
3416 	ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
3417 
3418 	switch (idev->cnf.addr_gen_mode) {
3419 	case IN6_ADDR_GEN_MODE_RANDOM:
3420 		ipv6_gen_mode_random_init(idev);
3421 		fallthrough;
3422 	case IN6_ADDR_GEN_MODE_STABLE_PRIVACY:
3423 		if (!ipv6_generate_stable_address(&addr, 0, idev))
3424 			addrconf_add_linklocal(idev, &addr,
3425 					       IFA_F_STABLE_PRIVACY);
3426 		else if (prefix_route)
3427 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3428 					      0, 0, GFP_KERNEL);
3429 		break;
3430 	case IN6_ADDR_GEN_MODE_EUI64:
3431 		/* addrconf_add_linklocal also adds a prefix_route and we
3432 		 * only need to care about prefix routes if ipv6_generate_eui64
3433 		 * couldn't generate one.
3434 		 */
3435 		if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
3436 			addrconf_add_linklocal(idev, &addr, 0);
3437 		else if (prefix_route)
3438 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3439 					      0, 0, GFP_KERNEL);
3440 		break;
3441 	case IN6_ADDR_GEN_MODE_NONE:
3442 	default:
3443 		/* will not add any link local address */
3444 		break;
3445 	}
3446 }
3447 
addrconf_dev_config(struct net_device * dev)3448 static void addrconf_dev_config(struct net_device *dev)
3449 {
3450 	struct inet6_dev *idev;
3451 
3452 	ASSERT_RTNL();
3453 
3454 	if ((dev->type != ARPHRD_ETHER) &&
3455 	    (dev->type != ARPHRD_FDDI) &&
3456 	    (dev->type != ARPHRD_ARCNET) &&
3457 	    (dev->type != ARPHRD_INFINIBAND) &&
3458 	    (dev->type != ARPHRD_IEEE1394) &&
3459 	    (dev->type != ARPHRD_TUNNEL6) &&
3460 	    (dev->type != ARPHRD_6LOWPAN) &&
3461 	    (dev->type != ARPHRD_TUNNEL) &&
3462 	    (dev->type != ARPHRD_NONE) &&
3463 	    (dev->type != ARPHRD_RAWIP)) {
3464 		/* Alas, we support only Ethernet autoconfiguration. */
3465 		idev = __in6_dev_get(dev);
3466 		if (!IS_ERR_OR_NULL(idev) && dev->flags & IFF_UP &&
3467 		    dev->flags & IFF_MULTICAST)
3468 			ipv6_mc_up(idev);
3469 		return;
3470 	}
3471 
3472 	idev = addrconf_add_dev(dev);
3473 	if (IS_ERR(idev))
3474 		return;
3475 
3476 	/* this device type has no EUI support */
3477 	if (dev->type == ARPHRD_NONE &&
3478 	    idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)
3479 		WRITE_ONCE(idev->cnf.addr_gen_mode,
3480 			   IN6_ADDR_GEN_MODE_RANDOM);
3481 
3482 	addrconf_addr_gen(idev, false);
3483 }
3484 
3485 #if IS_ENABLED(CONFIG_IPV6_SIT)
addrconf_sit_config(struct net_device * dev)3486 static void addrconf_sit_config(struct net_device *dev)
3487 {
3488 	struct inet6_dev *idev;
3489 
3490 	ASSERT_RTNL();
3491 
3492 	/*
3493 	 * Configure the tunnel with one of our IPv4
3494 	 * addresses... we should configure all of
3495 	 * our v4 addrs in the tunnel
3496 	 */
3497 
3498 	idev = ipv6_find_idev(dev);
3499 	if (IS_ERR(idev)) {
3500 		pr_debug("%s: add_dev failed\n", __func__);
3501 		return;
3502 	}
3503 
3504 	if (dev->priv_flags & IFF_ISATAP) {
3505 		addrconf_addr_gen(idev, false);
3506 		return;
3507 	}
3508 
3509 	add_v4_addrs(idev);
3510 
3511 	if (dev->flags&IFF_POINTOPOINT)
3512 		addrconf_add_mroute(dev);
3513 }
3514 #endif
3515 
3516 #if IS_ENABLED(CONFIG_NET_IPGRE) || IS_ENABLED(CONFIG_IPV6_GRE)
addrconf_gre_config(struct net_device * dev)3517 static void addrconf_gre_config(struct net_device *dev)
3518 {
3519 	struct inet6_dev *idev;
3520 
3521 	ASSERT_RTNL();
3522 
3523 	idev = ipv6_find_idev(dev);
3524 	if (IS_ERR(idev)) {
3525 		pr_debug("%s: add_dev failed\n", __func__);
3526 		return;
3527 	}
3528 
3529 	/* Generate the IPv6 link-local address using addrconf_addr_gen(),
3530 	 * unless we have an IPv4 GRE device not bound to an IP address and
3531 	 * which is in EUI64 mode (as __ipv6_isatap_ifid() would fail in this
3532 	 * case). Such devices fall back to add_v4_addrs() instead.
3533 	 */
3534 	if (!(dev->type == ARPHRD_IPGRE && *(__be32 *)dev->dev_addr == 0 &&
3535 	      idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)) {
3536 		addrconf_addr_gen(idev, true);
3537 		return;
3538 	}
3539 
3540 	add_v4_addrs(idev);
3541 
3542 	if (dev->flags & IFF_POINTOPOINT)
3543 		addrconf_add_mroute(dev);
3544 }
3545 #endif
3546 
addrconf_init_auto_addrs(struct net_device * dev)3547 static void addrconf_init_auto_addrs(struct net_device *dev)
3548 {
3549 	switch (dev->type) {
3550 #if IS_ENABLED(CONFIG_IPV6_SIT)
3551 	case ARPHRD_SIT:
3552 		addrconf_sit_config(dev);
3553 		break;
3554 #endif
3555 #if IS_ENABLED(CONFIG_NET_IPGRE) || IS_ENABLED(CONFIG_IPV6_GRE)
3556 	case ARPHRD_IP6GRE:
3557 	case ARPHRD_IPGRE:
3558 		addrconf_gre_config(dev);
3559 		break;
3560 #endif
3561 	case ARPHRD_LOOPBACK:
3562 		init_loopback(dev);
3563 		break;
3564 
3565 	default:
3566 		addrconf_dev_config(dev);
3567 		break;
3568 	}
3569 }
3570 
fixup_permanent_addr(struct net * net,struct inet6_dev * idev,struct inet6_ifaddr * ifp)3571 static int fixup_permanent_addr(struct net *net,
3572 				struct inet6_dev *idev,
3573 				struct inet6_ifaddr *ifp)
3574 {
3575 	/* !fib6_node means the host route was removed from the
3576 	 * FIB, for example, if 'lo' device is taken down. In that
3577 	 * case regenerate the host route.
3578 	 */
3579 	if (!ifp->rt || !ifp->rt->fib6_node) {
3580 		struct fib6_info *f6i, *prev;
3581 
3582 		f6i = addrconf_f6i_alloc(net, idev, &ifp->addr, false,
3583 					 GFP_ATOMIC, NULL);
3584 		if (IS_ERR(f6i))
3585 			return PTR_ERR(f6i);
3586 
3587 		/* ifp->rt can be accessed outside of rtnl */
3588 		spin_lock(&ifp->lock);
3589 		prev = ifp->rt;
3590 		ifp->rt = f6i;
3591 		spin_unlock(&ifp->lock);
3592 
3593 		fib6_info_release(prev);
3594 	}
3595 
3596 	if (!(ifp->flags & IFA_F_NOPREFIXROUTE)) {
3597 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3598 				      ifp->rt_priority, idev->dev, 0, 0,
3599 				      GFP_ATOMIC);
3600 	}
3601 
3602 	if (ifp->state == INET6_IFADDR_STATE_PREDAD)
3603 		addrconf_dad_start(ifp);
3604 
3605 	return 0;
3606 }
3607 
addrconf_permanent_addr(struct net * net,struct net_device * dev)3608 static void addrconf_permanent_addr(struct net *net, struct net_device *dev)
3609 {
3610 	struct inet6_ifaddr *ifp, *tmp;
3611 	struct inet6_dev *idev;
3612 
3613 	idev = __in6_dev_get(dev);
3614 	if (!idev)
3615 		return;
3616 
3617 	write_lock_bh(&idev->lock);
3618 
3619 	list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
3620 		if ((ifp->flags & IFA_F_PERMANENT) &&
3621 		    fixup_permanent_addr(net, idev, ifp) < 0) {
3622 			write_unlock_bh(&idev->lock);
3623 			in6_ifa_hold(ifp);
3624 			ipv6_del_addr(ifp);
3625 			write_lock_bh(&idev->lock);
3626 
3627 			net_info_ratelimited("%s: Failed to add prefix route for address %pI6c; dropping\n",
3628 					     idev->dev->name, &ifp->addr);
3629 		}
3630 	}
3631 
3632 	write_unlock_bh(&idev->lock);
3633 }
3634 
addrconf_notify(struct notifier_block * this,unsigned long event,void * ptr)3635 static int addrconf_notify(struct notifier_block *this, unsigned long event,
3636 			   void *ptr)
3637 {
3638 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3639 	struct netdev_notifier_change_info *change_info;
3640 	struct netdev_notifier_changeupper_info *info;
3641 	struct inet6_dev *idev = __in6_dev_get(dev);
3642 	struct net *net = dev_net(dev);
3643 	int run_pending = 0;
3644 	int err;
3645 
3646 	switch (event) {
3647 	case NETDEV_REGISTER:
3648 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3649 			idev = ipv6_add_dev(dev);
3650 			if (IS_ERR(idev))
3651 				return notifier_from_errno(PTR_ERR(idev));
3652 		}
3653 		break;
3654 
3655 	case NETDEV_CHANGEMTU:
3656 		/* if MTU under IPV6_MIN_MTU stop IPv6 on this interface. */
3657 		if (dev->mtu < IPV6_MIN_MTU) {
3658 			addrconf_ifdown(dev, dev != net->loopback_dev);
3659 			break;
3660 		}
3661 
3662 		if (idev) {
3663 			rt6_mtu_change(dev, dev->mtu);
3664 			WRITE_ONCE(idev->cnf.mtu6, dev->mtu);
3665 			break;
3666 		}
3667 
3668 		/* allocate new idev */
3669 		idev = ipv6_add_dev(dev);
3670 		if (IS_ERR(idev))
3671 			break;
3672 
3673 		/* device is still not ready */
3674 		if (!(idev->if_flags & IF_READY))
3675 			break;
3676 
3677 		run_pending = 1;
3678 		fallthrough;
3679 	case NETDEV_UP:
3680 	case NETDEV_CHANGE:
3681 		if (idev && idev->cnf.disable_ipv6)
3682 			break;
3683 
3684 		if (dev->priv_flags & IFF_NO_ADDRCONF) {
3685 			if (event == NETDEV_UP && !IS_ERR_OR_NULL(idev) &&
3686 			    dev->flags & IFF_UP && dev->flags & IFF_MULTICAST)
3687 				ipv6_mc_up(idev);
3688 			break;
3689 		}
3690 
3691 		if (event == NETDEV_UP) {
3692 			/* restore routes for permanent addresses */
3693 			addrconf_permanent_addr(net, dev);
3694 
3695 			if (!addrconf_link_ready(dev)) {
3696 				/* device is not ready yet. */
3697 				pr_debug("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
3698 					 dev->name);
3699 				break;
3700 			}
3701 
3702 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
3703 				idev = ipv6_add_dev(dev);
3704 
3705 			if (!IS_ERR_OR_NULL(idev)) {
3706 				idev->if_flags |= IF_READY;
3707 				run_pending = 1;
3708 			}
3709 		} else if (event == NETDEV_CHANGE) {
3710 			if (!addrconf_link_ready(dev)) {
3711 				/* device is still not ready. */
3712 				rt6_sync_down_dev(dev, event);
3713 				break;
3714 			}
3715 
3716 			if (!IS_ERR_OR_NULL(idev)) {
3717 				if (idev->if_flags & IF_READY) {
3718 					/* device is already configured -
3719 					 * but resend MLD reports, we might
3720 					 * have roamed and need to update
3721 					 * multicast snooping switches
3722 					 */
3723 					ipv6_mc_up(idev);
3724 					change_info = ptr;
3725 					if (change_info->flags_changed & IFF_NOARP)
3726 						addrconf_dad_run(idev, true);
3727 					rt6_sync_up(dev, RTNH_F_LINKDOWN);
3728 					break;
3729 				}
3730 				idev->if_flags |= IF_READY;
3731 			}
3732 
3733 			pr_debug("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
3734 				 dev->name);
3735 
3736 			run_pending = 1;
3737 		}
3738 
3739 		addrconf_init_auto_addrs(dev);
3740 
3741 		if (!IS_ERR_OR_NULL(idev)) {
3742 			if (run_pending)
3743 				addrconf_dad_run(idev, false);
3744 
3745 			/* Device has an address by now */
3746 			rt6_sync_up(dev, RTNH_F_DEAD);
3747 
3748 			/*
3749 			 * If the MTU changed during the interface down,
3750 			 * when the interface up, the changed MTU must be
3751 			 * reflected in the idev as well as routers.
3752 			 */
3753 			if (idev->cnf.mtu6 != dev->mtu &&
3754 			    dev->mtu >= IPV6_MIN_MTU) {
3755 				rt6_mtu_change(dev, dev->mtu);
3756 				WRITE_ONCE(idev->cnf.mtu6, dev->mtu);
3757 			}
3758 			WRITE_ONCE(idev->tstamp, jiffies);
3759 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
3760 
3761 			/*
3762 			 * If the changed mtu during down is lower than
3763 			 * IPV6_MIN_MTU stop IPv6 on this interface.
3764 			 */
3765 			if (dev->mtu < IPV6_MIN_MTU)
3766 				addrconf_ifdown(dev, dev != net->loopback_dev);
3767 		}
3768 		break;
3769 
3770 	case NETDEV_DOWN:
3771 	case NETDEV_UNREGISTER:
3772 		/*
3773 		 *	Remove all addresses from this interface.
3774 		 */
3775 		addrconf_ifdown(dev, event != NETDEV_DOWN);
3776 		break;
3777 
3778 	case NETDEV_CHANGENAME:
3779 		if (idev) {
3780 			snmp6_unregister_dev(idev);
3781 			addrconf_sysctl_unregister(idev);
3782 			err = addrconf_sysctl_register(idev);
3783 			if (err)
3784 				return notifier_from_errno(err);
3785 			err = snmp6_register_dev(idev);
3786 			if (err) {
3787 				addrconf_sysctl_unregister(idev);
3788 				return notifier_from_errno(err);
3789 			}
3790 		}
3791 		break;
3792 
3793 	case NETDEV_PRE_TYPE_CHANGE:
3794 	case NETDEV_POST_TYPE_CHANGE:
3795 		if (idev)
3796 			addrconf_type_change(dev, event);
3797 		break;
3798 
3799 	case NETDEV_CHANGEUPPER:
3800 		info = ptr;
3801 
3802 		/* flush all routes if dev is linked to or unlinked from
3803 		 * an L3 master device (e.g., VRF)
3804 		 */
3805 		if (info->upper_dev && netif_is_l3_master(info->upper_dev))
3806 			addrconf_ifdown(dev, false);
3807 	}
3808 
3809 	return NOTIFY_OK;
3810 }
3811 
3812 /*
3813  *	addrconf module should be notified of a device going up
3814  */
3815 static struct notifier_block ipv6_dev_notf = {
3816 	.notifier_call = addrconf_notify,
3817 	.priority = ADDRCONF_NOTIFY_PRIORITY,
3818 };
3819 
addrconf_type_change(struct net_device * dev,unsigned long event)3820 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3821 {
3822 	struct inet6_dev *idev;
3823 	ASSERT_RTNL();
3824 
3825 	idev = __in6_dev_get(dev);
3826 
3827 	if (event == NETDEV_POST_TYPE_CHANGE)
3828 		ipv6_mc_remap(idev);
3829 	else if (event == NETDEV_PRE_TYPE_CHANGE)
3830 		ipv6_mc_unmap(idev);
3831 }
3832 
addr_is_local(const struct in6_addr * addr)3833 static bool addr_is_local(const struct in6_addr *addr)
3834 {
3835 	return ipv6_addr_type(addr) &
3836 		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
3837 }
3838 
addrconf_ifdown(struct net_device * dev,bool unregister)3839 static int addrconf_ifdown(struct net_device *dev, bool unregister)
3840 {
3841 	unsigned long event = unregister ? NETDEV_UNREGISTER : NETDEV_DOWN;
3842 	struct net *net = dev_net(dev);
3843 	struct inet6_dev *idev;
3844 	struct inet6_ifaddr *ifa;
3845 	LIST_HEAD(tmp_addr_list);
3846 	bool keep_addr = false;
3847 	bool was_ready;
3848 	int state, i;
3849 
3850 	ASSERT_RTNL();
3851 
3852 	rt6_disable_ip(dev, event);
3853 
3854 	idev = __in6_dev_get(dev);
3855 	if (!idev)
3856 		return -ENODEV;
3857 
3858 	/*
3859 	 * Step 1: remove reference to ipv6 device from parent device.
3860 	 *	   Do not dev_put!
3861 	 */
3862 	if (unregister) {
3863 		idev->dead = 1;
3864 
3865 		/* protected by rtnl_lock */
3866 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3867 
3868 		/* Step 1.5: remove snmp6 entry */
3869 		snmp6_unregister_dev(idev);
3870 
3871 	}
3872 
3873 	/* combine the user config with event to determine if permanent
3874 	 * addresses are to be removed from address hash table
3875 	 */
3876 	if (!unregister && !idev->cnf.disable_ipv6) {
3877 		/* aggregate the system setting and interface setting */
3878 		int _keep_addr = READ_ONCE(net->ipv6.devconf_all->keep_addr_on_down);
3879 
3880 		if (!_keep_addr)
3881 			_keep_addr = READ_ONCE(idev->cnf.keep_addr_on_down);
3882 
3883 		keep_addr = (_keep_addr > 0);
3884 	}
3885 
3886 	/* Step 2: clear hash table */
3887 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3888 		struct hlist_head *h = &net->ipv6.inet6_addr_lst[i];
3889 
3890 		spin_lock_bh(&net->ipv6.addrconf_hash_lock);
3891 restart:
3892 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3893 			if (ifa->idev == idev) {
3894 				addrconf_del_dad_work(ifa);
3895 				/* combined flag + permanent flag decide if
3896 				 * address is retained on a down event
3897 				 */
3898 				if (!keep_addr ||
3899 				    !(ifa->flags & IFA_F_PERMANENT) ||
3900 				    addr_is_local(&ifa->addr)) {
3901 					hlist_del_init_rcu(&ifa->addr_lst);
3902 					goto restart;
3903 				}
3904 			}
3905 		}
3906 		spin_unlock_bh(&net->ipv6.addrconf_hash_lock);
3907 	}
3908 
3909 	write_lock_bh(&idev->lock);
3910 
3911 	addrconf_del_rs_timer(idev);
3912 
3913 	/* Step 2: clear flags for stateless addrconf, repeated down
3914 	 *         detection
3915 	 */
3916 	was_ready = idev->if_flags & IF_READY;
3917 	if (!unregister)
3918 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3919 
3920 	/* Step 3: clear tempaddr list */
3921 	while (!list_empty(&idev->tempaddr_list)) {
3922 		ifa = list_first_entry(&idev->tempaddr_list,
3923 				       struct inet6_ifaddr, tmp_list);
3924 		list_del(&ifa->tmp_list);
3925 		write_unlock_bh(&idev->lock);
3926 		spin_lock_bh(&ifa->lock);
3927 
3928 		if (ifa->ifpub) {
3929 			in6_ifa_put(ifa->ifpub);
3930 			ifa->ifpub = NULL;
3931 		}
3932 		spin_unlock_bh(&ifa->lock);
3933 		in6_ifa_put(ifa);
3934 		write_lock_bh(&idev->lock);
3935 	}
3936 
3937 	list_for_each_entry(ifa, &idev->addr_list, if_list)
3938 		list_add_tail(&ifa->if_list_aux, &tmp_addr_list);
3939 	write_unlock_bh(&idev->lock);
3940 
3941 	while (!list_empty(&tmp_addr_list)) {
3942 		struct fib6_info *rt = NULL;
3943 		bool keep;
3944 
3945 		ifa = list_first_entry(&tmp_addr_list,
3946 				       struct inet6_ifaddr, if_list_aux);
3947 		list_del(&ifa->if_list_aux);
3948 
3949 		addrconf_del_dad_work(ifa);
3950 
3951 		keep = keep_addr && (ifa->flags & IFA_F_PERMANENT) &&
3952 			!addr_is_local(&ifa->addr);
3953 
3954 		spin_lock_bh(&ifa->lock);
3955 
3956 		if (keep) {
3957 			/* set state to skip the notifier below */
3958 			state = INET6_IFADDR_STATE_DEAD;
3959 			ifa->state = INET6_IFADDR_STATE_PREDAD;
3960 			if (!(ifa->flags & IFA_F_NODAD))
3961 				ifa->flags |= IFA_F_TENTATIVE;
3962 
3963 			rt = ifa->rt;
3964 			ifa->rt = NULL;
3965 		} else {
3966 			state = ifa->state;
3967 			ifa->state = INET6_IFADDR_STATE_DEAD;
3968 		}
3969 
3970 		spin_unlock_bh(&ifa->lock);
3971 
3972 		if (rt)
3973 			ip6_del_rt(net, rt, false);
3974 
3975 		if (state != INET6_IFADDR_STATE_DEAD) {
3976 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3977 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3978 		} else {
3979 			if (idev->cnf.forwarding)
3980 				addrconf_leave_anycast(ifa);
3981 			addrconf_leave_solict(ifa->idev, &ifa->addr);
3982 		}
3983 
3984 		if (!keep) {
3985 			write_lock_bh(&idev->lock);
3986 			list_del_rcu(&ifa->if_list);
3987 			write_unlock_bh(&idev->lock);
3988 			in6_ifa_put(ifa);
3989 		}
3990 	}
3991 
3992 	/* Step 5: Discard anycast and multicast list */
3993 	if (unregister) {
3994 		ipv6_ac_destroy_dev(idev);
3995 		ipv6_mc_destroy_dev(idev);
3996 	} else if (was_ready) {
3997 		ipv6_mc_down(idev);
3998 	}
3999 
4000 	WRITE_ONCE(idev->tstamp, jiffies);
4001 	idev->ra_mtu = 0;
4002 
4003 	/* Last: Shot the device (if unregistered) */
4004 	if (unregister) {
4005 		addrconf_sysctl_unregister(idev);
4006 		neigh_parms_release(&nd_tbl, idev->nd_parms);
4007 		neigh_ifdown(&nd_tbl, dev);
4008 		in6_dev_put(idev);
4009 	}
4010 	return 0;
4011 }
4012 
addrconf_rs_timer(struct timer_list * t)4013 static void addrconf_rs_timer(struct timer_list *t)
4014 {
4015 	struct inet6_dev *idev = from_timer(idev, t, rs_timer);
4016 	struct net_device *dev = idev->dev;
4017 	struct in6_addr lladdr;
4018 	int rtr_solicits;
4019 
4020 	write_lock(&idev->lock);
4021 	if (idev->dead || !(idev->if_flags & IF_READY))
4022 		goto out;
4023 
4024 	if (!ipv6_accept_ra(idev))
4025 		goto out;
4026 
4027 	/* Announcement received after solicitation was sent */
4028 	if (idev->if_flags & IF_RA_RCVD)
4029 		goto out;
4030 
4031 	rtr_solicits = READ_ONCE(idev->cnf.rtr_solicits);
4032 
4033 	if (idev->rs_probes++ < rtr_solicits || rtr_solicits < 0) {
4034 		write_unlock(&idev->lock);
4035 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4036 			ndisc_send_rs(dev, &lladdr,
4037 				      &in6addr_linklocal_allrouters);
4038 		else
4039 			goto put;
4040 
4041 		write_lock(&idev->lock);
4042 		idev->rs_interval = rfc3315_s14_backoff_update(
4043 				idev->rs_interval,
4044 				READ_ONCE(idev->cnf.rtr_solicit_max_interval));
4045 		/* The wait after the last probe can be shorter */
4046 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
4047 					     READ_ONCE(idev->cnf.rtr_solicits)) ?
4048 				      READ_ONCE(idev->cnf.rtr_solicit_delay) :
4049 				      idev->rs_interval);
4050 	} else {
4051 		/*
4052 		 * Note: we do not support deprecated "all on-link"
4053 		 * assumption any longer.
4054 		 */
4055 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
4056 	}
4057 
4058 out:
4059 	write_unlock(&idev->lock);
4060 put:
4061 	in6_dev_put(idev);
4062 }
4063 
4064 /*
4065  *	Duplicate Address Detection
4066  */
addrconf_dad_kick(struct inet6_ifaddr * ifp)4067 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
4068 {
4069 	struct inet6_dev *idev = ifp->idev;
4070 	unsigned long rand_num;
4071 	u64 nonce;
4072 
4073 	if (ifp->flags & IFA_F_OPTIMISTIC)
4074 		rand_num = 0;
4075 	else
4076 		rand_num = get_random_u32_below(
4077 				READ_ONCE(idev->cnf.rtr_solicit_delay) ? : 1);
4078 
4079 	nonce = 0;
4080 	if (READ_ONCE(idev->cnf.enhanced_dad) ||
4081 	    READ_ONCE(dev_net(idev->dev)->ipv6.devconf_all->enhanced_dad)) {
4082 		do
4083 			get_random_bytes(&nonce, 6);
4084 		while (nonce == 0);
4085 	}
4086 	ifp->dad_nonce = nonce;
4087 	ifp->dad_probes = READ_ONCE(idev->cnf.dad_transmits);
4088 	addrconf_mod_dad_work(ifp, rand_num);
4089 }
4090 
addrconf_dad_begin(struct inet6_ifaddr * ifp)4091 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
4092 {
4093 	struct inet6_dev *idev = ifp->idev;
4094 	struct net_device *dev = idev->dev;
4095 	bool bump_id, notify = false;
4096 	struct net *net;
4097 
4098 	addrconf_join_solict(dev, &ifp->addr);
4099 
4100 	read_lock_bh(&idev->lock);
4101 	spin_lock(&ifp->lock);
4102 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
4103 		goto out;
4104 
4105 	net = dev_net(dev);
4106 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
4107 	    (READ_ONCE(net->ipv6.devconf_all->accept_dad) < 1 &&
4108 	     READ_ONCE(idev->cnf.accept_dad) < 1) ||
4109 	    !(ifp->flags&IFA_F_TENTATIVE) ||
4110 	    ifp->flags & IFA_F_NODAD) {
4111 		bool send_na = false;
4112 
4113 		if (ifp->flags & IFA_F_TENTATIVE &&
4114 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4115 			send_na = true;
4116 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4117 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4118 		spin_unlock(&ifp->lock);
4119 		read_unlock_bh(&idev->lock);
4120 
4121 		addrconf_dad_completed(ifp, bump_id, send_na);
4122 		return;
4123 	}
4124 
4125 	if (!(idev->if_flags & IF_READY)) {
4126 		spin_unlock(&ifp->lock);
4127 		read_unlock_bh(&idev->lock);
4128 		/*
4129 		 * If the device is not ready:
4130 		 * - keep it tentative if it is a permanent address.
4131 		 * - otherwise, kill it.
4132 		 */
4133 		in6_ifa_hold(ifp);
4134 		addrconf_dad_stop(ifp, 0);
4135 		return;
4136 	}
4137 
4138 	/*
4139 	 * Optimistic nodes can start receiving
4140 	 * Frames right away
4141 	 */
4142 	if (ifp->flags & IFA_F_OPTIMISTIC) {
4143 		ip6_ins_rt(net, ifp->rt);
4144 		if (ipv6_use_optimistic_addr(net, idev)) {
4145 			/* Because optimistic nodes can use this address,
4146 			 * notify listeners. If DAD fails, RTM_DELADDR is sent.
4147 			 */
4148 			notify = true;
4149 		}
4150 	}
4151 
4152 	addrconf_dad_kick(ifp);
4153 out:
4154 	spin_unlock(&ifp->lock);
4155 	read_unlock_bh(&idev->lock);
4156 	if (notify)
4157 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
4158 }
4159 
addrconf_dad_start(struct inet6_ifaddr * ifp)4160 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
4161 {
4162 	bool begin_dad = false;
4163 
4164 	spin_lock_bh(&ifp->lock);
4165 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
4166 		ifp->state = INET6_IFADDR_STATE_PREDAD;
4167 		begin_dad = true;
4168 	}
4169 	spin_unlock_bh(&ifp->lock);
4170 
4171 	if (begin_dad)
4172 		addrconf_mod_dad_work(ifp, 0);
4173 }
4174 
addrconf_dad_work(struct work_struct * w)4175 static void addrconf_dad_work(struct work_struct *w)
4176 {
4177 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
4178 						struct inet6_ifaddr,
4179 						dad_work);
4180 	struct inet6_dev *idev = ifp->idev;
4181 	bool bump_id, disable_ipv6 = false;
4182 	struct in6_addr mcaddr;
4183 	struct net *net;
4184 
4185 	enum {
4186 		DAD_PROCESS,
4187 		DAD_BEGIN,
4188 		DAD_ABORT,
4189 	} action = DAD_PROCESS;
4190 
4191 	net = dev_net(idev->dev);
4192 
4193 	rtnl_net_lock(net);
4194 
4195 	spin_lock_bh(&ifp->lock);
4196 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
4197 		action = DAD_BEGIN;
4198 		ifp->state = INET6_IFADDR_STATE_DAD;
4199 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
4200 		action = DAD_ABORT;
4201 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
4202 
4203 		if ((READ_ONCE(net->ipv6.devconf_all->accept_dad) > 1 ||
4204 		     READ_ONCE(idev->cnf.accept_dad) > 1) &&
4205 		    !idev->cnf.disable_ipv6 &&
4206 		    !(ifp->flags & IFA_F_STABLE_PRIVACY)) {
4207 			struct in6_addr addr;
4208 
4209 			addr.s6_addr32[0] = htonl(0xfe800000);
4210 			addr.s6_addr32[1] = 0;
4211 
4212 			if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
4213 			    ipv6_addr_equal(&ifp->addr, &addr)) {
4214 				/* DAD failed for link-local based on MAC */
4215 				WRITE_ONCE(idev->cnf.disable_ipv6, 1);
4216 
4217 				pr_info("%s: IPv6 being disabled!\n",
4218 					ifp->idev->dev->name);
4219 				disable_ipv6 = true;
4220 			}
4221 		}
4222 	}
4223 	spin_unlock_bh(&ifp->lock);
4224 
4225 	if (action == DAD_BEGIN) {
4226 		addrconf_dad_begin(ifp);
4227 		goto out;
4228 	} else if (action == DAD_ABORT) {
4229 		in6_ifa_hold(ifp);
4230 		addrconf_dad_stop(ifp, 1);
4231 		if (disable_ipv6)
4232 			addrconf_ifdown(idev->dev, false);
4233 		goto out;
4234 	}
4235 
4236 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
4237 		goto out;
4238 
4239 	write_lock_bh(&idev->lock);
4240 	if (idev->dead || !(idev->if_flags & IF_READY)) {
4241 		write_unlock_bh(&idev->lock);
4242 		goto out;
4243 	}
4244 
4245 	spin_lock(&ifp->lock);
4246 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
4247 		spin_unlock(&ifp->lock);
4248 		write_unlock_bh(&idev->lock);
4249 		goto out;
4250 	}
4251 
4252 	if (ifp->dad_probes == 0) {
4253 		bool send_na = false;
4254 
4255 		/*
4256 		 * DAD was successful
4257 		 */
4258 
4259 		if (ifp->flags & IFA_F_TENTATIVE &&
4260 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4261 			send_na = true;
4262 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4263 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4264 		spin_unlock(&ifp->lock);
4265 		write_unlock_bh(&idev->lock);
4266 
4267 		addrconf_dad_completed(ifp, bump_id, send_na);
4268 
4269 		goto out;
4270 	}
4271 
4272 	ifp->dad_probes--;
4273 	addrconf_mod_dad_work(ifp,
4274 			      max(NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME),
4275 				  HZ/100));
4276 	spin_unlock(&ifp->lock);
4277 	write_unlock_bh(&idev->lock);
4278 
4279 	/* send a neighbour solicitation for our addr */
4280 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
4281 	ndisc_send_ns(ifp->idev->dev, &ifp->addr, &mcaddr, &in6addr_any,
4282 		      ifp->dad_nonce);
4283 out:
4284 	in6_ifa_put(ifp);
4285 	rtnl_net_unlock(net);
4286 }
4287 
4288 /* ifp->idev must be at least read locked */
ipv6_lonely_lladdr(struct inet6_ifaddr * ifp)4289 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
4290 {
4291 	struct inet6_ifaddr *ifpiter;
4292 	struct inet6_dev *idev = ifp->idev;
4293 
4294 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
4295 		if (ifpiter->scope > IFA_LINK)
4296 			break;
4297 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
4298 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
4299 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
4300 		    IFA_F_PERMANENT)
4301 			return false;
4302 	}
4303 	return true;
4304 }
4305 
addrconf_dad_completed(struct inet6_ifaddr * ifp,bool bump_id,bool send_na)4306 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
4307 				   bool send_na)
4308 {
4309 	struct net_device *dev = ifp->idev->dev;
4310 	struct in6_addr lladdr;
4311 	bool send_rs, send_mld;
4312 
4313 	addrconf_del_dad_work(ifp);
4314 
4315 	/*
4316 	 *	Configure the address for reception. Now it is valid.
4317 	 */
4318 
4319 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
4320 
4321 	/* If added prefix is link local and we are prepared to process
4322 	   router advertisements, start sending router solicitations.
4323 	 */
4324 
4325 	read_lock_bh(&ifp->idev->lock);
4326 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
4327 	send_rs = send_mld &&
4328 		  ipv6_accept_ra(ifp->idev) &&
4329 		  READ_ONCE(ifp->idev->cnf.rtr_solicits) != 0 &&
4330 		  (dev->flags & IFF_LOOPBACK) == 0 &&
4331 		  (dev->type != ARPHRD_TUNNEL) &&
4332 		  !netif_is_team_port(dev);
4333 	read_unlock_bh(&ifp->idev->lock);
4334 
4335 	/* While dad is in progress mld report's source address is in6_addrany.
4336 	 * Resend with proper ll now.
4337 	 */
4338 	if (send_mld)
4339 		ipv6_mc_dad_complete(ifp->idev);
4340 
4341 	/* send unsolicited NA if enabled */
4342 	if (send_na &&
4343 	    (READ_ONCE(ifp->idev->cnf.ndisc_notify) ||
4344 	     READ_ONCE(dev_net(dev)->ipv6.devconf_all->ndisc_notify))) {
4345 		ndisc_send_na(dev, &in6addr_linklocal_allnodes, &ifp->addr,
4346 			      /*router=*/ !!ifp->idev->cnf.forwarding,
4347 			      /*solicited=*/ false, /*override=*/ true,
4348 			      /*inc_opt=*/ true);
4349 	}
4350 
4351 	if (send_rs) {
4352 		/*
4353 		 *	If a host as already performed a random delay
4354 		 *	[...] as part of DAD [...] there is no need
4355 		 *	to delay again before sending the first RS
4356 		 */
4357 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4358 			return;
4359 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
4360 
4361 		write_lock_bh(&ifp->idev->lock);
4362 		spin_lock(&ifp->lock);
4363 		ifp->idev->rs_interval = rfc3315_s14_backoff_init(
4364 			READ_ONCE(ifp->idev->cnf.rtr_solicit_interval));
4365 		ifp->idev->rs_probes = 1;
4366 		ifp->idev->if_flags |= IF_RS_SENT;
4367 		addrconf_mod_rs_timer(ifp->idev, ifp->idev->rs_interval);
4368 		spin_unlock(&ifp->lock);
4369 		write_unlock_bh(&ifp->idev->lock);
4370 	}
4371 
4372 	if (bump_id)
4373 		rt_genid_bump_ipv6(dev_net(dev));
4374 
4375 	/* Make sure that a new temporary address will be created
4376 	 * before this temporary address becomes deprecated.
4377 	 */
4378 	if (ifp->flags & IFA_F_TEMPORARY)
4379 		addrconf_verify_rtnl(dev_net(dev));
4380 }
4381 
addrconf_dad_run(struct inet6_dev * idev,bool restart)4382 static void addrconf_dad_run(struct inet6_dev *idev, bool restart)
4383 {
4384 	struct inet6_ifaddr *ifp;
4385 
4386 	read_lock_bh(&idev->lock);
4387 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4388 		spin_lock(&ifp->lock);
4389 		if ((ifp->flags & IFA_F_TENTATIVE &&
4390 		     ifp->state == INET6_IFADDR_STATE_DAD) || restart) {
4391 			if (restart)
4392 				ifp->state = INET6_IFADDR_STATE_PREDAD;
4393 			addrconf_dad_kick(ifp);
4394 		}
4395 		spin_unlock(&ifp->lock);
4396 	}
4397 	read_unlock_bh(&idev->lock);
4398 }
4399 
4400 #ifdef CONFIG_PROC_FS
4401 struct if6_iter_state {
4402 	struct seq_net_private p;
4403 	int bucket;
4404 	int offset;
4405 };
4406 
if6_get_first(struct seq_file * seq,loff_t pos)4407 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
4408 {
4409 	struct if6_iter_state *state = seq->private;
4410 	struct net *net = seq_file_net(seq);
4411 	struct inet6_ifaddr *ifa = NULL;
4412 	int p = 0;
4413 
4414 	/* initial bucket if pos is 0 */
4415 	if (pos == 0) {
4416 		state->bucket = 0;
4417 		state->offset = 0;
4418 	}
4419 
4420 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
4421 		hlist_for_each_entry_rcu(ifa, &net->ipv6.inet6_addr_lst[state->bucket],
4422 					 addr_lst) {
4423 			/* sync with offset */
4424 			if (p < state->offset) {
4425 				p++;
4426 				continue;
4427 			}
4428 			return ifa;
4429 		}
4430 
4431 		/* prepare for next bucket */
4432 		state->offset = 0;
4433 		p = 0;
4434 	}
4435 	return NULL;
4436 }
4437 
if6_get_next(struct seq_file * seq,struct inet6_ifaddr * ifa)4438 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
4439 					 struct inet6_ifaddr *ifa)
4440 {
4441 	struct if6_iter_state *state = seq->private;
4442 	struct net *net = seq_file_net(seq);
4443 
4444 	hlist_for_each_entry_continue_rcu(ifa, addr_lst) {
4445 		state->offset++;
4446 		return ifa;
4447 	}
4448 
4449 	state->offset = 0;
4450 	while (++state->bucket < IN6_ADDR_HSIZE) {
4451 		hlist_for_each_entry_rcu(ifa,
4452 				     &net->ipv6.inet6_addr_lst[state->bucket], addr_lst) {
4453 			return ifa;
4454 		}
4455 	}
4456 
4457 	return NULL;
4458 }
4459 
if6_seq_start(struct seq_file * seq,loff_t * pos)4460 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
4461 	__acquires(rcu)
4462 {
4463 	rcu_read_lock();
4464 	return if6_get_first(seq, *pos);
4465 }
4466 
if6_seq_next(struct seq_file * seq,void * v,loff_t * pos)4467 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4468 {
4469 	struct inet6_ifaddr *ifa;
4470 
4471 	ifa = if6_get_next(seq, v);
4472 	++*pos;
4473 	return ifa;
4474 }
4475 
if6_seq_stop(struct seq_file * seq,void * v)4476 static void if6_seq_stop(struct seq_file *seq, void *v)
4477 	__releases(rcu)
4478 {
4479 	rcu_read_unlock();
4480 }
4481 
if6_seq_show(struct seq_file * seq,void * v)4482 static int if6_seq_show(struct seq_file *seq, void *v)
4483 {
4484 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
4485 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
4486 		   &ifp->addr,
4487 		   ifp->idev->dev->ifindex,
4488 		   ifp->prefix_len,
4489 		   ifp->scope,
4490 		   (u8) ifp->flags,
4491 		   ifp->idev->dev->name);
4492 	return 0;
4493 }
4494 
4495 static const struct seq_operations if6_seq_ops = {
4496 	.start	= if6_seq_start,
4497 	.next	= if6_seq_next,
4498 	.show	= if6_seq_show,
4499 	.stop	= if6_seq_stop,
4500 };
4501 
if6_proc_net_init(struct net * net)4502 static int __net_init if6_proc_net_init(struct net *net)
4503 {
4504 	if (!proc_create_net("if_inet6", 0444, net->proc_net, &if6_seq_ops,
4505 			sizeof(struct if6_iter_state)))
4506 		return -ENOMEM;
4507 	return 0;
4508 }
4509 
if6_proc_net_exit(struct net * net)4510 static void __net_exit if6_proc_net_exit(struct net *net)
4511 {
4512 	remove_proc_entry("if_inet6", net->proc_net);
4513 }
4514 
4515 static struct pernet_operations if6_proc_net_ops = {
4516 	.init = if6_proc_net_init,
4517 	.exit = if6_proc_net_exit,
4518 };
4519 
if6_proc_init(void)4520 int __init if6_proc_init(void)
4521 {
4522 	return register_pernet_subsys(&if6_proc_net_ops);
4523 }
4524 
if6_proc_exit(void)4525 void if6_proc_exit(void)
4526 {
4527 	unregister_pernet_subsys(&if6_proc_net_ops);
4528 }
4529 #endif	/* CONFIG_PROC_FS */
4530 
4531 #if IS_ENABLED(CONFIG_IPV6_MIP6)
4532 /* Check if address is a home address configured on any interface. */
ipv6_chk_home_addr(struct net * net,const struct in6_addr * addr)4533 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
4534 {
4535 	unsigned int hash = inet6_addr_hash(net, addr);
4536 	struct inet6_ifaddr *ifp = NULL;
4537 	int ret = 0;
4538 
4539 	rcu_read_lock();
4540 	hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
4541 		if (ipv6_addr_equal(&ifp->addr, addr) &&
4542 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
4543 			ret = 1;
4544 			break;
4545 		}
4546 	}
4547 	rcu_read_unlock();
4548 	return ret;
4549 }
4550 #endif
4551 
4552 /* RFC6554 has some algorithm to avoid loops in segment routing by
4553  * checking if the segments contains any of a local interface address.
4554  *
4555  * Quote:
4556  *
4557  * To detect loops in the SRH, a router MUST determine if the SRH
4558  * includes multiple addresses assigned to any interface on that router.
4559  * If such addresses appear more than once and are separated by at least
4560  * one address not assigned to that router.
4561  */
ipv6_chk_rpl_srh_loop(struct net * net,const struct in6_addr * segs,unsigned char nsegs)4562 int ipv6_chk_rpl_srh_loop(struct net *net, const struct in6_addr *segs,
4563 			  unsigned char nsegs)
4564 {
4565 	const struct in6_addr *addr;
4566 	int i, ret = 0, found = 0;
4567 	struct inet6_ifaddr *ifp;
4568 	bool separated = false;
4569 	unsigned int hash;
4570 	bool hash_found;
4571 
4572 	rcu_read_lock();
4573 	for (i = 0; i < nsegs; i++) {
4574 		addr = &segs[i];
4575 		hash = inet6_addr_hash(net, addr);
4576 
4577 		hash_found = false;
4578 		hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
4579 
4580 			if (ipv6_addr_equal(&ifp->addr, addr)) {
4581 				hash_found = true;
4582 				break;
4583 			}
4584 		}
4585 
4586 		if (hash_found) {
4587 			if (found > 1 && separated) {
4588 				ret = 1;
4589 				break;
4590 			}
4591 
4592 			separated = false;
4593 			found++;
4594 		} else {
4595 			separated = true;
4596 		}
4597 	}
4598 	rcu_read_unlock();
4599 
4600 	return ret;
4601 }
4602 
4603 /*
4604  *	Periodic address status verification
4605  */
4606 
addrconf_verify_rtnl(struct net * net)4607 static void addrconf_verify_rtnl(struct net *net)
4608 {
4609 	unsigned long now, next, next_sec, next_sched;
4610 	struct inet6_ifaddr *ifp;
4611 	int i;
4612 
4613 	ASSERT_RTNL();
4614 
4615 	rcu_read_lock_bh();
4616 	now = jiffies;
4617 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
4618 
4619 	cancel_delayed_work(&net->ipv6.addr_chk_work);
4620 
4621 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
4622 restart:
4623 		hlist_for_each_entry_rcu_bh(ifp, &net->ipv6.inet6_addr_lst[i], addr_lst) {
4624 			unsigned long age;
4625 
4626 			/* When setting preferred_lft to a value not zero or
4627 			 * infinity, while valid_lft is infinity
4628 			 * IFA_F_PERMANENT has a non-infinity life time.
4629 			 */
4630 			if ((ifp->flags & IFA_F_PERMANENT) &&
4631 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
4632 				continue;
4633 
4634 			spin_lock(&ifp->lock);
4635 			/* We try to batch several events at once. */
4636 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
4637 
4638 			if ((ifp->flags&IFA_F_TEMPORARY) &&
4639 			    !(ifp->flags&IFA_F_TENTATIVE) &&
4640 			    ifp->prefered_lft != INFINITY_LIFE_TIME &&
4641 			    !ifp->regen_count && ifp->ifpub) {
4642 				/* This is a non-regenerated temporary addr. */
4643 
4644 				unsigned long regen_advance = ipv6_get_regen_advance(ifp->idev);
4645 
4646 				if (age + regen_advance >= ifp->prefered_lft) {
4647 					struct inet6_ifaddr *ifpub = ifp->ifpub;
4648 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4649 						next = ifp->tstamp + ifp->prefered_lft * HZ;
4650 
4651 					ifp->regen_count++;
4652 					in6_ifa_hold(ifp);
4653 					in6_ifa_hold(ifpub);
4654 					spin_unlock(&ifp->lock);
4655 
4656 					spin_lock(&ifpub->lock);
4657 					ifpub->regen_count = 0;
4658 					spin_unlock(&ifpub->lock);
4659 					rcu_read_unlock_bh();
4660 					ipv6_create_tempaddr(ifpub, true);
4661 					in6_ifa_put(ifpub);
4662 					in6_ifa_put(ifp);
4663 					rcu_read_lock_bh();
4664 					goto restart;
4665 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
4666 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
4667 			}
4668 
4669 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
4670 			    age >= ifp->valid_lft) {
4671 				spin_unlock(&ifp->lock);
4672 				in6_ifa_hold(ifp);
4673 				rcu_read_unlock_bh();
4674 				ipv6_del_addr(ifp);
4675 				rcu_read_lock_bh();
4676 				goto restart;
4677 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
4678 				spin_unlock(&ifp->lock);
4679 				continue;
4680 			} else if (age >= ifp->prefered_lft) {
4681 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
4682 				int deprecate = 0;
4683 
4684 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
4685 					deprecate = 1;
4686 					ifp->flags |= IFA_F_DEPRECATED;
4687 				}
4688 
4689 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
4690 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
4691 					next = ifp->tstamp + ifp->valid_lft * HZ;
4692 
4693 				spin_unlock(&ifp->lock);
4694 
4695 				if (deprecate) {
4696 					in6_ifa_hold(ifp);
4697 
4698 					ipv6_ifa_notify(0, ifp);
4699 					in6_ifa_put(ifp);
4700 					goto restart;
4701 				}
4702 			} else {
4703 				/* ifp->prefered_lft <= ifp->valid_lft */
4704 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4705 					next = ifp->tstamp + ifp->prefered_lft * HZ;
4706 				spin_unlock(&ifp->lock);
4707 			}
4708 		}
4709 	}
4710 
4711 	next_sec = round_jiffies_up(next);
4712 	next_sched = next;
4713 
4714 	/* If rounded timeout is accurate enough, accept it. */
4715 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
4716 		next_sched = next_sec;
4717 
4718 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
4719 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
4720 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
4721 
4722 	pr_debug("now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
4723 		 now, next, next_sec, next_sched);
4724 	mod_delayed_work(addrconf_wq, &net->ipv6.addr_chk_work, next_sched - now);
4725 	rcu_read_unlock_bh();
4726 }
4727 
addrconf_verify_work(struct work_struct * w)4728 static void addrconf_verify_work(struct work_struct *w)
4729 {
4730 	struct net *net = container_of(to_delayed_work(w), struct net,
4731 				       ipv6.addr_chk_work);
4732 
4733 	rtnl_net_lock(net);
4734 	addrconf_verify_rtnl(net);
4735 	rtnl_net_unlock(net);
4736 }
4737 
addrconf_verify(struct net * net)4738 static void addrconf_verify(struct net *net)
4739 {
4740 	mod_delayed_work(addrconf_wq, &net->ipv6.addr_chk_work, 0);
4741 }
4742 
extract_addr(struct nlattr * addr,struct nlattr * local,struct in6_addr ** peer_pfx)4743 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
4744 				     struct in6_addr **peer_pfx)
4745 {
4746 	struct in6_addr *pfx = NULL;
4747 
4748 	*peer_pfx = NULL;
4749 
4750 	if (addr)
4751 		pfx = nla_data(addr);
4752 
4753 	if (local) {
4754 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
4755 			*peer_pfx = pfx;
4756 		pfx = nla_data(local);
4757 	}
4758 
4759 	return pfx;
4760 }
4761 
4762 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
4763 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
4764 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
4765 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
4766 	[IFA_FLAGS]		= { .len = sizeof(u32) },
4767 	[IFA_RT_PRIORITY]	= { .len = sizeof(u32) },
4768 	[IFA_TARGET_NETNSID]	= { .type = NLA_S32 },
4769 	[IFA_PROTO]		= { .type = NLA_U8 },
4770 };
4771 
4772 static int
inet6_rtm_deladdr(struct sk_buff * skb,struct nlmsghdr * nlh,struct netlink_ext_ack * extack)4773 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
4774 		  struct netlink_ext_ack *extack)
4775 {
4776 	struct net *net = sock_net(skb->sk);
4777 	struct ifaddrmsg *ifm;
4778 	struct nlattr *tb[IFA_MAX+1];
4779 	struct in6_addr *pfx, *peer_pfx;
4780 	u32 ifa_flags;
4781 	int err;
4782 
4783 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4784 				     ifa_ipv6_policy, extack);
4785 	if (err < 0)
4786 		return err;
4787 
4788 	ifm = nlmsg_data(nlh);
4789 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4790 	if (!pfx)
4791 		return -EINVAL;
4792 
4793 	ifa_flags = nla_get_u32_default(tb[IFA_FLAGS], ifm->ifa_flags);
4794 
4795 	/* We ignore other flags so far. */
4796 	ifa_flags &= IFA_F_MANAGETEMPADDR;
4797 
4798 	rtnl_net_lock(net);
4799 	err = inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
4800 			     ifm->ifa_prefixlen, extack);
4801 	rtnl_net_unlock(net);
4802 
4803 	return err;
4804 }
4805 
modify_prefix_route(struct net * net,struct inet6_ifaddr * ifp,unsigned long expires,u32 flags,bool modify_peer)4806 static int modify_prefix_route(struct net *net, struct inet6_ifaddr *ifp,
4807 			       unsigned long expires, u32 flags,
4808 			       bool modify_peer)
4809 {
4810 	struct fib6_table *table;
4811 	struct fib6_info *f6i;
4812 	u32 prio;
4813 
4814 	f6i = addrconf_get_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
4815 					ifp->prefix_len,
4816 					ifp->idev->dev, 0, RTF_DEFAULT, true);
4817 	if (!f6i)
4818 		return -ENOENT;
4819 
4820 	prio = ifp->rt_priority ? : IP6_RT_PRIO_ADDRCONF;
4821 	if (f6i->fib6_metric != prio) {
4822 		/* delete old one */
4823 		ip6_del_rt(dev_net(ifp->idev->dev), f6i, false);
4824 
4825 		/* add new one */
4826 		addrconf_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
4827 				      ifp->prefix_len,
4828 				      ifp->rt_priority, ifp->idev->dev,
4829 				      expires, flags, GFP_KERNEL);
4830 		return 0;
4831 	}
4832 	if (f6i != net->ipv6.fib6_null_entry) {
4833 		table = f6i->fib6_table;
4834 		spin_lock_bh(&table->tb6_lock);
4835 
4836 		if (!(flags & RTF_EXPIRES)) {
4837 			fib6_clean_expires(f6i);
4838 			fib6_remove_gc_list(f6i);
4839 		} else {
4840 			fib6_set_expires(f6i, expires);
4841 			fib6_add_gc_list(f6i);
4842 		}
4843 
4844 		spin_unlock_bh(&table->tb6_lock);
4845 	}
4846 	fib6_info_release(f6i);
4847 
4848 	return 0;
4849 }
4850 
inet6_addr_modify(struct net * net,struct inet6_ifaddr * ifp,struct ifa6_config * cfg,clock_t expires,u32 flags)4851 static int inet6_addr_modify(struct net *net, struct inet6_ifaddr *ifp,
4852 			     struct ifa6_config *cfg, clock_t expires,
4853 			     u32 flags)
4854 {
4855 	bool was_managetempaddr;
4856 	bool new_peer = false;
4857 	bool had_prefixroute;
4858 
4859 	ASSERT_RTNL_NET(net);
4860 
4861 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR &&
4862 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
4863 		return -EINVAL;
4864 
4865 	if (!(ifp->flags & IFA_F_TENTATIVE) || ifp->flags & IFA_F_DADFAILED)
4866 		cfg->ifa_flags &= ~IFA_F_OPTIMISTIC;
4867 
4868 	if (cfg->peer_pfx &&
4869 	    memcmp(&ifp->peer_addr, cfg->peer_pfx, sizeof(struct in6_addr))) {
4870 		if (!ipv6_addr_any(&ifp->peer_addr))
4871 			cleanup_prefix_route(ifp, expires, true, true);
4872 		new_peer = true;
4873 	}
4874 
4875 	spin_lock_bh(&ifp->lock);
4876 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
4877 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
4878 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
4879 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
4880 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4881 			IFA_F_NOPREFIXROUTE);
4882 	ifp->flags |= cfg->ifa_flags;
4883 	WRITE_ONCE(ifp->tstamp, jiffies);
4884 	WRITE_ONCE(ifp->valid_lft, cfg->valid_lft);
4885 	WRITE_ONCE(ifp->prefered_lft, cfg->preferred_lft);
4886 	WRITE_ONCE(ifp->ifa_proto, cfg->ifa_proto);
4887 
4888 	if (cfg->rt_priority && cfg->rt_priority != ifp->rt_priority)
4889 		WRITE_ONCE(ifp->rt_priority, cfg->rt_priority);
4890 
4891 	if (new_peer)
4892 		ifp->peer_addr = *cfg->peer_pfx;
4893 
4894 	spin_unlock_bh(&ifp->lock);
4895 	if (!(ifp->flags&IFA_F_TENTATIVE))
4896 		ipv6_ifa_notify(0, ifp);
4897 
4898 	if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
4899 		int rc = -ENOENT;
4900 
4901 		if (had_prefixroute)
4902 			rc = modify_prefix_route(net, ifp, expires, flags, false);
4903 
4904 		/* prefix route could have been deleted; if so restore it */
4905 		if (rc == -ENOENT) {
4906 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
4907 					      ifp->rt_priority, ifp->idev->dev,
4908 					      expires, flags, GFP_KERNEL);
4909 		}
4910 
4911 		if (had_prefixroute && !ipv6_addr_any(&ifp->peer_addr))
4912 			rc = modify_prefix_route(net, ifp, expires, flags, true);
4913 
4914 		if (rc == -ENOENT && !ipv6_addr_any(&ifp->peer_addr)) {
4915 			addrconf_prefix_route(&ifp->peer_addr, ifp->prefix_len,
4916 					      ifp->rt_priority, ifp->idev->dev,
4917 					      expires, flags, GFP_KERNEL);
4918 		}
4919 	} else if (had_prefixroute) {
4920 		enum cleanup_prefix_rt_t action;
4921 		unsigned long rt_expires;
4922 
4923 		write_lock_bh(&ifp->idev->lock);
4924 		action = check_cleanup_prefix_route(ifp, &rt_expires);
4925 		write_unlock_bh(&ifp->idev->lock);
4926 
4927 		if (action != CLEANUP_PREFIX_RT_NOP) {
4928 			cleanup_prefix_route(ifp, rt_expires,
4929 				action == CLEANUP_PREFIX_RT_DEL, false);
4930 		}
4931 	}
4932 
4933 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
4934 		if (was_managetempaddr && !(ifp->flags & IFA_F_MANAGETEMPADDR))
4935 			delete_tempaddrs(ifp->idev, ifp);
4936 		else
4937 			manage_tempaddrs(ifp->idev, ifp, cfg->valid_lft,
4938 					 cfg->preferred_lft, !was_managetempaddr,
4939 					 jiffies);
4940 	}
4941 
4942 	addrconf_verify_rtnl(net);
4943 
4944 	return 0;
4945 }
4946 
4947 static int
inet6_rtm_newaddr(struct sk_buff * skb,struct nlmsghdr * nlh,struct netlink_ext_ack * extack)4948 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
4949 		  struct netlink_ext_ack *extack)
4950 {
4951 	struct net *net = sock_net(skb->sk);
4952 	struct nlattr *tb[IFA_MAX+1];
4953 	struct in6_addr *peer_pfx;
4954 	struct inet6_ifaddr *ifa;
4955 	struct net_device *dev;
4956 	struct inet6_dev *idev;
4957 	struct ifa6_config cfg;
4958 	struct ifaddrmsg *ifm;
4959 	unsigned long timeout;
4960 	clock_t expires;
4961 	u32 flags;
4962 	int err;
4963 
4964 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4965 				     ifa_ipv6_policy, extack);
4966 	if (err < 0)
4967 		return err;
4968 
4969 	memset(&cfg, 0, sizeof(cfg));
4970 
4971 	ifm = nlmsg_data(nlh);
4972 	cfg.pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4973 	if (!cfg.pfx)
4974 		return -EINVAL;
4975 
4976 	cfg.peer_pfx = peer_pfx;
4977 	cfg.plen = ifm->ifa_prefixlen;
4978 	if (tb[IFA_RT_PRIORITY])
4979 		cfg.rt_priority = nla_get_u32(tb[IFA_RT_PRIORITY]);
4980 
4981 	if (tb[IFA_PROTO])
4982 		cfg.ifa_proto = nla_get_u8(tb[IFA_PROTO]);
4983 
4984 	cfg.ifa_flags = nla_get_u32_default(tb[IFA_FLAGS], ifm->ifa_flags);
4985 
4986 	/* We ignore other flags so far. */
4987 	cfg.ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS |
4988 			 IFA_F_MANAGETEMPADDR | IFA_F_NOPREFIXROUTE |
4989 			 IFA_F_MCAUTOJOIN | IFA_F_OPTIMISTIC;
4990 
4991 	cfg.ifa_flags |= IFA_F_PERMANENT;
4992 	cfg.valid_lft = INFINITY_LIFE_TIME;
4993 	cfg.preferred_lft = INFINITY_LIFE_TIME;
4994 	expires = 0;
4995 	flags = 0;
4996 
4997 	if (tb[IFA_CACHEINFO]) {
4998 		struct ifa_cacheinfo *ci;
4999 
5000 		ci = nla_data(tb[IFA_CACHEINFO]);
5001 		cfg.valid_lft = ci->ifa_valid;
5002 		cfg.preferred_lft = ci->ifa_prefered;
5003 
5004 		if (!cfg.valid_lft || cfg.preferred_lft > cfg.valid_lft) {
5005 			NL_SET_ERR_MSG_MOD(extack, "address lifetime invalid");
5006 			return -EINVAL;
5007 		}
5008 
5009 		timeout = addrconf_timeout_fixup(cfg.valid_lft, HZ);
5010 		if (addrconf_finite_timeout(timeout)) {
5011 			cfg.ifa_flags &= ~IFA_F_PERMANENT;
5012 			cfg.valid_lft = timeout;
5013 			expires = jiffies_to_clock_t(timeout * HZ);
5014 			flags = RTF_EXPIRES;
5015 		}
5016 
5017 		timeout = addrconf_timeout_fixup(cfg.preferred_lft, HZ);
5018 		if (addrconf_finite_timeout(timeout)) {
5019 			if (timeout == 0)
5020 				cfg.ifa_flags |= IFA_F_DEPRECATED;
5021 
5022 			cfg.preferred_lft = timeout;
5023 		}
5024 	}
5025 
5026 	rtnl_net_lock(net);
5027 
5028 	dev =  __dev_get_by_index(net, ifm->ifa_index);
5029 	if (!dev) {
5030 		NL_SET_ERR_MSG_MOD(extack, "Unable to find the interface");
5031 		err = -ENODEV;
5032 		goto unlock;
5033 	}
5034 
5035 	idev = ipv6_find_idev(dev);
5036 	if (IS_ERR(idev)) {
5037 		err = PTR_ERR(idev);
5038 		goto unlock;
5039 	}
5040 
5041 	if (!ipv6_allow_optimistic_dad(net, idev))
5042 		cfg.ifa_flags &= ~IFA_F_OPTIMISTIC;
5043 
5044 	if (cfg.ifa_flags & IFA_F_NODAD &&
5045 	    cfg.ifa_flags & IFA_F_OPTIMISTIC) {
5046 		NL_SET_ERR_MSG(extack, "IFA_F_NODAD and IFA_F_OPTIMISTIC are mutually exclusive");
5047 		err = -EINVAL;
5048 		goto unlock;
5049 	}
5050 
5051 	ifa = ipv6_get_ifaddr(net, cfg.pfx, dev, 1);
5052 	if (!ifa) {
5053 		/*
5054 		 * It would be best to check for !NLM_F_CREATE here but
5055 		 * userspace already relies on not having to provide this.
5056 		 */
5057 		err = inet6_addr_add(net, dev, &cfg, expires, flags, extack);
5058 		goto unlock;
5059 	}
5060 
5061 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
5062 	    !(nlh->nlmsg_flags & NLM_F_REPLACE)) {
5063 		NL_SET_ERR_MSG_MOD(extack, "address already assigned");
5064 		err = -EEXIST;
5065 	} else {
5066 		err = inet6_addr_modify(net, ifa, &cfg, expires, flags);
5067 	}
5068 
5069 	in6_ifa_put(ifa);
5070 unlock:
5071 	rtnl_net_unlock(net);
5072 
5073 	return err;
5074 }
5075 
put_ifaddrmsg(struct nlmsghdr * nlh,u8 prefixlen,u32 flags,u8 scope,int ifindex)5076 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
5077 			  u8 scope, int ifindex)
5078 {
5079 	struct ifaddrmsg *ifm;
5080 
5081 	ifm = nlmsg_data(nlh);
5082 	ifm->ifa_family = AF_INET6;
5083 	ifm->ifa_prefixlen = prefixlen;
5084 	ifm->ifa_flags = flags;
5085 	ifm->ifa_scope = scope;
5086 	ifm->ifa_index = ifindex;
5087 }
5088 
put_cacheinfo(struct sk_buff * skb,unsigned long cstamp,unsigned long tstamp,u32 preferred,u32 valid)5089 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
5090 			 unsigned long tstamp, u32 preferred, u32 valid)
5091 {
5092 	struct ifa_cacheinfo ci;
5093 
5094 	ci.cstamp = cstamp_delta(cstamp);
5095 	ci.tstamp = cstamp_delta(tstamp);
5096 	ci.ifa_prefered = preferred;
5097 	ci.ifa_valid = valid;
5098 
5099 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
5100 }
5101 
rt_scope(int ifa_scope)5102 static inline int rt_scope(int ifa_scope)
5103 {
5104 	if (ifa_scope & IFA_HOST)
5105 		return RT_SCOPE_HOST;
5106 	else if (ifa_scope & IFA_LINK)
5107 		return RT_SCOPE_LINK;
5108 	else if (ifa_scope & IFA_SITE)
5109 		return RT_SCOPE_SITE;
5110 	else
5111 		return RT_SCOPE_UNIVERSE;
5112 }
5113 
inet6_ifaddr_msgsize(void)5114 static inline int inet6_ifaddr_msgsize(void)
5115 {
5116 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
5117 	       + nla_total_size(16) /* IFA_LOCAL */
5118 	       + nla_total_size(16) /* IFA_ADDRESS */
5119 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
5120 	       + nla_total_size(4)  /* IFA_FLAGS */
5121 	       + nla_total_size(1)  /* IFA_PROTO */
5122 	       + nla_total_size(4)  /* IFA_RT_PRIORITY */;
5123 }
5124 
inet6_fill_ifaddr(struct sk_buff * skb,const struct inet6_ifaddr * ifa,struct inet6_fill_args * args)5125 static int inet6_fill_ifaddr(struct sk_buff *skb,
5126 			     const struct inet6_ifaddr *ifa,
5127 			     struct inet6_fill_args *args)
5128 {
5129 	struct nlmsghdr *nlh;
5130 	u32 preferred, valid;
5131 	u32 flags, priority;
5132 	u8 proto;
5133 
5134 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5135 			sizeof(struct ifaddrmsg), args->flags);
5136 	if (!nlh)
5137 		return -EMSGSIZE;
5138 
5139 	flags = READ_ONCE(ifa->flags);
5140 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
5141 		      ifa->idev->dev->ifindex);
5142 
5143 	if (args->netnsid >= 0 &&
5144 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
5145 		goto error;
5146 
5147 	preferred = READ_ONCE(ifa->prefered_lft);
5148 	valid = READ_ONCE(ifa->valid_lft);
5149 
5150 	if (!((flags & IFA_F_PERMANENT) &&
5151 	      (preferred == INFINITY_LIFE_TIME))) {
5152 		if (preferred != INFINITY_LIFE_TIME) {
5153 			long tval = (jiffies - READ_ONCE(ifa->tstamp)) / HZ;
5154 
5155 			if (preferred > tval)
5156 				preferred -= tval;
5157 			else
5158 				preferred = 0;
5159 			if (valid != INFINITY_LIFE_TIME) {
5160 				if (valid > tval)
5161 					valid -= tval;
5162 				else
5163 					valid = 0;
5164 			}
5165 		}
5166 	} else {
5167 		preferred = INFINITY_LIFE_TIME;
5168 		valid = INFINITY_LIFE_TIME;
5169 	}
5170 
5171 	if (!ipv6_addr_any(&ifa->peer_addr)) {
5172 		if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||
5173 		    nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0)
5174 			goto error;
5175 	} else {
5176 		if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0)
5177 			goto error;
5178 	}
5179 
5180 	priority = READ_ONCE(ifa->rt_priority);
5181 	if (priority && nla_put_u32(skb, IFA_RT_PRIORITY, priority))
5182 		goto error;
5183 
5184 	if (put_cacheinfo(skb, ifa->cstamp, READ_ONCE(ifa->tstamp),
5185 			  preferred, valid) < 0)
5186 		goto error;
5187 
5188 	if (nla_put_u32(skb, IFA_FLAGS, flags) < 0)
5189 		goto error;
5190 
5191 	proto = READ_ONCE(ifa->ifa_proto);
5192 	if (proto && nla_put_u8(skb, IFA_PROTO, proto))
5193 		goto error;
5194 
5195 	nlmsg_end(skb, nlh);
5196 	return 0;
5197 
5198 error:
5199 	nlmsg_cancel(skb, nlh);
5200 	return -EMSGSIZE;
5201 }
5202 
inet6_fill_ifmcaddr(struct sk_buff * skb,const struct ifmcaddr6 * ifmca,struct inet6_fill_args * args)5203 int inet6_fill_ifmcaddr(struct sk_buff *skb,
5204 			const struct ifmcaddr6 *ifmca,
5205 			struct inet6_fill_args *args)
5206 {
5207 	int ifindex = ifmca->idev->dev->ifindex;
5208 	u8 scope = RT_SCOPE_UNIVERSE;
5209 	struct nlmsghdr *nlh;
5210 
5211 	if (!args->force_rt_scope_universe &&
5212 	    ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
5213 		scope = RT_SCOPE_SITE;
5214 
5215 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5216 			sizeof(struct ifaddrmsg), args->flags);
5217 	if (!nlh)
5218 		return -EMSGSIZE;
5219 
5220 	if (args->netnsid >= 0 &&
5221 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid)) {
5222 		nlmsg_cancel(skb, nlh);
5223 		return -EMSGSIZE;
5224 	}
5225 
5226 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
5227 	if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
5228 	    put_cacheinfo(skb, ifmca->mca_cstamp, READ_ONCE(ifmca->mca_tstamp),
5229 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
5230 		nlmsg_cancel(skb, nlh);
5231 		return -EMSGSIZE;
5232 	}
5233 
5234 	nlmsg_end(skb, nlh);
5235 	return 0;
5236 }
5237 
inet6_fill_ifacaddr(struct sk_buff * skb,const struct ifacaddr6 * ifaca,struct inet6_fill_args * args)5238 int inet6_fill_ifacaddr(struct sk_buff *skb,
5239 			const struct ifacaddr6 *ifaca,
5240 			struct inet6_fill_args *args)
5241 {
5242 	struct net_device *dev = fib6_info_nh_dev(ifaca->aca_rt);
5243 	int ifindex = dev ? dev->ifindex : 1;
5244 	u8 scope = RT_SCOPE_UNIVERSE;
5245 	struct nlmsghdr *nlh;
5246 
5247 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
5248 		scope = RT_SCOPE_SITE;
5249 
5250 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5251 			sizeof(struct ifaddrmsg), args->flags);
5252 	if (!nlh)
5253 		return -EMSGSIZE;
5254 
5255 	if (args->netnsid >= 0 &&
5256 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid)) {
5257 		nlmsg_cancel(skb, nlh);
5258 		return -EMSGSIZE;
5259 	}
5260 
5261 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
5262 	if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
5263 	    put_cacheinfo(skb, ifaca->aca_cstamp, READ_ONCE(ifaca->aca_tstamp),
5264 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
5265 		nlmsg_cancel(skb, nlh);
5266 		return -EMSGSIZE;
5267 	}
5268 
5269 	nlmsg_end(skb, nlh);
5270 	return 0;
5271 }
5272 
5273 /* 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)5274 static int in6_dump_addrs(const struct inet6_dev *idev, struct sk_buff *skb,
5275 			  struct netlink_callback *cb, int *s_ip_idx,
5276 			  struct inet6_fill_args *fillargs)
5277 {
5278 	const struct ifmcaddr6 *ifmca;
5279 	const struct ifacaddr6 *ifaca;
5280 	int ip_idx = 0;
5281 	int err = 0;
5282 
5283 	switch (fillargs->type) {
5284 	case UNICAST_ADDR: {
5285 		const struct inet6_ifaddr *ifa;
5286 		fillargs->event = RTM_NEWADDR;
5287 
5288 		/* unicast address incl. temp addr */
5289 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
5290 			if (ip_idx < *s_ip_idx)
5291 				goto next;
5292 			err = inet6_fill_ifaddr(skb, ifa, fillargs);
5293 			if (err < 0)
5294 				break;
5295 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
5296 next:
5297 			ip_idx++;
5298 		}
5299 		break;
5300 	}
5301 	case MULTICAST_ADDR:
5302 		fillargs->event = RTM_GETMULTICAST;
5303 
5304 		/* multicast address */
5305 		for (ifmca = rcu_dereference(idev->mc_list);
5306 		     ifmca;
5307 		     ifmca = rcu_dereference(ifmca->next), ip_idx++) {
5308 			if (ip_idx < *s_ip_idx)
5309 				continue;
5310 			err = inet6_fill_ifmcaddr(skb, ifmca, fillargs);
5311 			if (err < 0)
5312 				break;
5313 		}
5314 		break;
5315 	case ANYCAST_ADDR:
5316 		fillargs->event = RTM_GETANYCAST;
5317 		/* anycast address */
5318 		for (ifaca = rcu_dereference(idev->ac_list); ifaca;
5319 		     ifaca = rcu_dereference(ifaca->aca_next), ip_idx++) {
5320 			if (ip_idx < *s_ip_idx)
5321 				continue;
5322 			err = inet6_fill_ifacaddr(skb, ifaca, fillargs);
5323 			if (err < 0)
5324 				break;
5325 		}
5326 		break;
5327 	default:
5328 		break;
5329 	}
5330 	*s_ip_idx = err ? ip_idx : 0;
5331 	return err;
5332 }
5333 
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)5334 static int inet6_valid_dump_ifaddr_req(const struct nlmsghdr *nlh,
5335 				       struct inet6_fill_args *fillargs,
5336 				       struct net **tgt_net, struct sock *sk,
5337 				       struct netlink_callback *cb)
5338 {
5339 	struct netlink_ext_ack *extack = cb->extack;
5340 	struct nlattr *tb[IFA_MAX+1];
5341 	struct ifaddrmsg *ifm;
5342 	int err, i;
5343 
5344 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5345 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for address dump request");
5346 		return -EINVAL;
5347 	}
5348 
5349 	ifm = nlmsg_data(nlh);
5350 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5351 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for address dump request");
5352 		return -EINVAL;
5353 	}
5354 
5355 	fillargs->ifindex = ifm->ifa_index;
5356 	if (fillargs->ifindex) {
5357 		cb->answer_flags |= NLM_F_DUMP_FILTERED;
5358 		fillargs->flags |= NLM_F_DUMP_FILTERED;
5359 	}
5360 
5361 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5362 					    ifa_ipv6_policy, extack);
5363 	if (err < 0)
5364 		return err;
5365 
5366 	for (i = 0; i <= IFA_MAX; ++i) {
5367 		if (!tb[i])
5368 			continue;
5369 
5370 		if (i == IFA_TARGET_NETNSID) {
5371 			struct net *net;
5372 
5373 			fillargs->netnsid = nla_get_s32(tb[i]);
5374 			net = rtnl_get_net_ns_capable(sk, fillargs->netnsid);
5375 			if (IS_ERR(net)) {
5376 				fillargs->netnsid = -1;
5377 				NL_SET_ERR_MSG_MOD(extack, "Invalid target network namespace id");
5378 				return PTR_ERR(net);
5379 			}
5380 			*tgt_net = net;
5381 		} else {
5382 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in dump request");
5383 			return -EINVAL;
5384 		}
5385 	}
5386 
5387 	return 0;
5388 }
5389 
inet6_dump_addr(struct sk_buff * skb,struct netlink_callback * cb,enum addr_type_t type)5390 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
5391 			   enum addr_type_t type)
5392 {
5393 	struct net *tgt_net = sock_net(skb->sk);
5394 	const struct nlmsghdr *nlh = cb->nlh;
5395 	struct inet6_fill_args fillargs = {
5396 		.portid = NETLINK_CB(cb->skb).portid,
5397 		.seq = cb->nlh->nlmsg_seq,
5398 		.flags = NLM_F_MULTI,
5399 		.netnsid = -1,
5400 		.type = type,
5401 		.force_rt_scope_universe = false,
5402 	};
5403 	struct {
5404 		unsigned long ifindex;
5405 		int ip_idx;
5406 	} *ctx = (void *)cb->ctx;
5407 	struct net_device *dev;
5408 	struct inet6_dev *idev;
5409 	int err = 0;
5410 
5411 	rcu_read_lock();
5412 	if (cb->strict_check) {
5413 		err = inet6_valid_dump_ifaddr_req(nlh, &fillargs, &tgt_net,
5414 						  skb->sk, cb);
5415 		if (err < 0)
5416 			goto done;
5417 
5418 		err = 0;
5419 		if (fillargs.ifindex) {
5420 			dev = dev_get_by_index_rcu(tgt_net, fillargs.ifindex);
5421 			if (!dev) {
5422 				err = -ENODEV;
5423 				goto done;
5424 			}
5425 			idev = __in6_dev_get(dev);
5426 			if (idev)
5427 				err = in6_dump_addrs(idev, skb, cb,
5428 						     &ctx->ip_idx,
5429 						     &fillargs);
5430 			goto done;
5431 		}
5432 	}
5433 
5434 	cb->seq = inet6_base_seq(tgt_net);
5435 	for_each_netdev_dump(tgt_net, dev, ctx->ifindex) {
5436 		idev = __in6_dev_get(dev);
5437 		if (!idev)
5438 			continue;
5439 		err = in6_dump_addrs(idev, skb, cb, &ctx->ip_idx,
5440 				     &fillargs);
5441 		if (err < 0)
5442 			goto done;
5443 	}
5444 done:
5445 	rcu_read_unlock();
5446 	if (fillargs.netnsid >= 0)
5447 		put_net(tgt_net);
5448 
5449 	return err;
5450 }
5451 
inet6_dump_ifaddr(struct sk_buff * skb,struct netlink_callback * cb)5452 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
5453 {
5454 	enum addr_type_t type = UNICAST_ADDR;
5455 
5456 	return inet6_dump_addr(skb, cb, type);
5457 }
5458 
inet6_dump_ifmcaddr(struct sk_buff * skb,struct netlink_callback * cb)5459 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
5460 {
5461 	enum addr_type_t type = MULTICAST_ADDR;
5462 
5463 	return inet6_dump_addr(skb, cb, type);
5464 }
5465 
5466 
inet6_dump_ifacaddr(struct sk_buff * skb,struct netlink_callback * cb)5467 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
5468 {
5469 	enum addr_type_t type = ANYCAST_ADDR;
5470 
5471 	return inet6_dump_addr(skb, cb, type);
5472 }
5473 
inet6_rtm_valid_getaddr_req(struct sk_buff * skb,const struct nlmsghdr * nlh,struct nlattr ** tb,struct netlink_ext_ack * extack)5474 static int inet6_rtm_valid_getaddr_req(struct sk_buff *skb,
5475 				       const struct nlmsghdr *nlh,
5476 				       struct nlattr **tb,
5477 				       struct netlink_ext_ack *extack)
5478 {
5479 	struct ifaddrmsg *ifm;
5480 	int i, err;
5481 
5482 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5483 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for get address request");
5484 		return -EINVAL;
5485 	}
5486 
5487 	if (!netlink_strict_get_check(skb))
5488 		return nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
5489 					      ifa_ipv6_policy, extack);
5490 
5491 	ifm = nlmsg_data(nlh);
5492 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5493 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for get address request");
5494 		return -EINVAL;
5495 	}
5496 
5497 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5498 					    ifa_ipv6_policy, extack);
5499 	if (err)
5500 		return err;
5501 
5502 	for (i = 0; i <= IFA_MAX; i++) {
5503 		if (!tb[i])
5504 			continue;
5505 
5506 		switch (i) {
5507 		case IFA_TARGET_NETNSID:
5508 		case IFA_ADDRESS:
5509 		case IFA_LOCAL:
5510 			break;
5511 		default:
5512 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in get address request");
5513 			return -EINVAL;
5514 		}
5515 	}
5516 
5517 	return 0;
5518 }
5519 
inet6_rtm_getaddr(struct sk_buff * in_skb,struct nlmsghdr * nlh,struct netlink_ext_ack * extack)5520 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
5521 			     struct netlink_ext_ack *extack)
5522 {
5523 	struct net *tgt_net = sock_net(in_skb->sk);
5524 	struct inet6_fill_args fillargs = {
5525 		.portid = NETLINK_CB(in_skb).portid,
5526 		.seq = nlh->nlmsg_seq,
5527 		.event = RTM_NEWADDR,
5528 		.flags = 0,
5529 		.netnsid = -1,
5530 		.force_rt_scope_universe = false,
5531 	};
5532 	struct ifaddrmsg *ifm;
5533 	struct nlattr *tb[IFA_MAX+1];
5534 	struct in6_addr *addr = NULL, *peer;
5535 	struct net_device *dev = NULL;
5536 	struct inet6_ifaddr *ifa;
5537 	struct sk_buff *skb;
5538 	int err;
5539 
5540 	err = inet6_rtm_valid_getaddr_req(in_skb, nlh, tb, extack);
5541 	if (err < 0)
5542 		return err;
5543 
5544 	if (tb[IFA_TARGET_NETNSID]) {
5545 		fillargs.netnsid = nla_get_s32(tb[IFA_TARGET_NETNSID]);
5546 
5547 		tgt_net = rtnl_get_net_ns_capable(NETLINK_CB(in_skb).sk,
5548 						  fillargs.netnsid);
5549 		if (IS_ERR(tgt_net))
5550 			return PTR_ERR(tgt_net);
5551 	}
5552 
5553 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
5554 	if (!addr) {
5555 		err = -EINVAL;
5556 		goto errout;
5557 	}
5558 	ifm = nlmsg_data(nlh);
5559 	if (ifm->ifa_index)
5560 		dev = dev_get_by_index(tgt_net, ifm->ifa_index);
5561 
5562 	ifa = ipv6_get_ifaddr(tgt_net, addr, dev, 1);
5563 	if (!ifa) {
5564 		err = -EADDRNOTAVAIL;
5565 		goto errout;
5566 	}
5567 
5568 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
5569 	if (!skb) {
5570 		err = -ENOBUFS;
5571 		goto errout_ifa;
5572 	}
5573 
5574 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5575 	if (err < 0) {
5576 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5577 		WARN_ON(err == -EMSGSIZE);
5578 		kfree_skb(skb);
5579 		goto errout_ifa;
5580 	}
5581 	err = rtnl_unicast(skb, tgt_net, NETLINK_CB(in_skb).portid);
5582 errout_ifa:
5583 	in6_ifa_put(ifa);
5584 errout:
5585 	dev_put(dev);
5586 	if (fillargs.netnsid >= 0)
5587 		put_net(tgt_net);
5588 
5589 	return err;
5590 }
5591 
inet6_ifa_notify(int event,struct inet6_ifaddr * ifa)5592 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
5593 {
5594 	struct sk_buff *skb;
5595 	struct net *net = dev_net(ifa->idev->dev);
5596 	struct inet6_fill_args fillargs = {
5597 		.portid = 0,
5598 		.seq = 0,
5599 		.event = event,
5600 		.flags = 0,
5601 		.netnsid = -1,
5602 		.force_rt_scope_universe = false,
5603 	};
5604 	int err = -ENOBUFS;
5605 
5606 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
5607 	if (!skb)
5608 		goto errout;
5609 
5610 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5611 	if (err < 0) {
5612 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5613 		WARN_ON(err == -EMSGSIZE);
5614 		kfree_skb(skb);
5615 		goto errout;
5616 	}
5617 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
5618 	return;
5619 errout:
5620 	rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
5621 }
5622 
ipv6_store_devconf(const struct ipv6_devconf * cnf,__s32 * array,int bytes)5623 static void ipv6_store_devconf(const struct ipv6_devconf *cnf,
5624 			       __s32 *array, int bytes)
5625 {
5626 	BUG_ON(bytes < (DEVCONF_MAX * 4));
5627 
5628 	memset(array, 0, bytes);
5629 	array[DEVCONF_FORWARDING] = READ_ONCE(cnf->forwarding);
5630 	array[DEVCONF_HOPLIMIT] = READ_ONCE(cnf->hop_limit);
5631 	array[DEVCONF_MTU6] = READ_ONCE(cnf->mtu6);
5632 	array[DEVCONF_ACCEPT_RA] = READ_ONCE(cnf->accept_ra);
5633 	array[DEVCONF_ACCEPT_REDIRECTS] = READ_ONCE(cnf->accept_redirects);
5634 	array[DEVCONF_AUTOCONF] = READ_ONCE(cnf->autoconf);
5635 	array[DEVCONF_DAD_TRANSMITS] = READ_ONCE(cnf->dad_transmits);
5636 	array[DEVCONF_RTR_SOLICITS] = READ_ONCE(cnf->rtr_solicits);
5637 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
5638 		jiffies_to_msecs(READ_ONCE(cnf->rtr_solicit_interval));
5639 	array[DEVCONF_RTR_SOLICIT_MAX_INTERVAL] =
5640 		jiffies_to_msecs(READ_ONCE(cnf->rtr_solicit_max_interval));
5641 	array[DEVCONF_RTR_SOLICIT_DELAY] =
5642 		jiffies_to_msecs(READ_ONCE(cnf->rtr_solicit_delay));
5643 	array[DEVCONF_FORCE_MLD_VERSION] = READ_ONCE(cnf->force_mld_version);
5644 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
5645 		jiffies_to_msecs(READ_ONCE(cnf->mldv1_unsolicited_report_interval));
5646 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
5647 		jiffies_to_msecs(READ_ONCE(cnf->mldv2_unsolicited_report_interval));
5648 	array[DEVCONF_USE_TEMPADDR] = READ_ONCE(cnf->use_tempaddr);
5649 	array[DEVCONF_TEMP_VALID_LFT] = READ_ONCE(cnf->temp_valid_lft);
5650 	array[DEVCONF_TEMP_PREFERED_LFT] = READ_ONCE(cnf->temp_prefered_lft);
5651 	array[DEVCONF_REGEN_MAX_RETRY] = READ_ONCE(cnf->regen_max_retry);
5652 	array[DEVCONF_MAX_DESYNC_FACTOR] = READ_ONCE(cnf->max_desync_factor);
5653 	array[DEVCONF_MAX_ADDRESSES] = READ_ONCE(cnf->max_addresses);
5654 	array[DEVCONF_ACCEPT_RA_DEFRTR] = READ_ONCE(cnf->accept_ra_defrtr);
5655 	array[DEVCONF_RA_DEFRTR_METRIC] = READ_ONCE(cnf->ra_defrtr_metric);
5656 	array[DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT] =
5657 		READ_ONCE(cnf->accept_ra_min_hop_limit);
5658 	array[DEVCONF_ACCEPT_RA_PINFO] = READ_ONCE(cnf->accept_ra_pinfo);
5659 #ifdef CONFIG_IPV6_ROUTER_PREF
5660 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = READ_ONCE(cnf->accept_ra_rtr_pref);
5661 	array[DEVCONF_RTR_PROBE_INTERVAL] =
5662 		jiffies_to_msecs(READ_ONCE(cnf->rtr_probe_interval));
5663 #ifdef CONFIG_IPV6_ROUTE_INFO
5664 	array[DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN] =
5665 		READ_ONCE(cnf->accept_ra_rt_info_min_plen);
5666 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] =
5667 		READ_ONCE(cnf->accept_ra_rt_info_max_plen);
5668 #endif
5669 #endif
5670 	array[DEVCONF_PROXY_NDP] = READ_ONCE(cnf->proxy_ndp);
5671 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] =
5672 		READ_ONCE(cnf->accept_source_route);
5673 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5674 	array[DEVCONF_OPTIMISTIC_DAD] = READ_ONCE(cnf->optimistic_dad);
5675 	array[DEVCONF_USE_OPTIMISTIC] = READ_ONCE(cnf->use_optimistic);
5676 #endif
5677 #ifdef CONFIG_IPV6_MROUTE
5678 	array[DEVCONF_MC_FORWARDING] = atomic_read(&cnf->mc_forwarding);
5679 #endif
5680 	array[DEVCONF_DISABLE_IPV6] = READ_ONCE(cnf->disable_ipv6);
5681 	array[DEVCONF_ACCEPT_DAD] = READ_ONCE(cnf->accept_dad);
5682 	array[DEVCONF_FORCE_TLLAO] = READ_ONCE(cnf->force_tllao);
5683 	array[DEVCONF_NDISC_NOTIFY] = READ_ONCE(cnf->ndisc_notify);
5684 	array[DEVCONF_SUPPRESS_FRAG_NDISC] =
5685 		READ_ONCE(cnf->suppress_frag_ndisc);
5686 	array[DEVCONF_ACCEPT_RA_FROM_LOCAL] =
5687 		READ_ONCE(cnf->accept_ra_from_local);
5688 	array[DEVCONF_ACCEPT_RA_MTU] = READ_ONCE(cnf->accept_ra_mtu);
5689 	array[DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN] =
5690 		READ_ONCE(cnf->ignore_routes_with_linkdown);
5691 	/* we omit DEVCONF_STABLE_SECRET for now */
5692 	array[DEVCONF_USE_OIF_ADDRS_ONLY] = READ_ONCE(cnf->use_oif_addrs_only);
5693 	array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] =
5694 		READ_ONCE(cnf->drop_unicast_in_l2_multicast);
5695 	array[DEVCONF_DROP_UNSOLICITED_NA] = READ_ONCE(cnf->drop_unsolicited_na);
5696 	array[DEVCONF_KEEP_ADDR_ON_DOWN] = READ_ONCE(cnf->keep_addr_on_down);
5697 	array[DEVCONF_SEG6_ENABLED] = READ_ONCE(cnf->seg6_enabled);
5698 #ifdef CONFIG_IPV6_SEG6_HMAC
5699 	array[DEVCONF_SEG6_REQUIRE_HMAC] = READ_ONCE(cnf->seg6_require_hmac);
5700 #endif
5701 	array[DEVCONF_ENHANCED_DAD] = READ_ONCE(cnf->enhanced_dad);
5702 	array[DEVCONF_ADDR_GEN_MODE] = READ_ONCE(cnf->addr_gen_mode);
5703 	array[DEVCONF_DISABLE_POLICY] = READ_ONCE(cnf->disable_policy);
5704 	array[DEVCONF_NDISC_TCLASS] = READ_ONCE(cnf->ndisc_tclass);
5705 	array[DEVCONF_RPL_SEG_ENABLED] = READ_ONCE(cnf->rpl_seg_enabled);
5706 	array[DEVCONF_IOAM6_ENABLED] = READ_ONCE(cnf->ioam6_enabled);
5707 	array[DEVCONF_IOAM6_ID] = READ_ONCE(cnf->ioam6_id);
5708 	array[DEVCONF_IOAM6_ID_WIDE] = READ_ONCE(cnf->ioam6_id_wide);
5709 	array[DEVCONF_NDISC_EVICT_NOCARRIER] =
5710 		READ_ONCE(cnf->ndisc_evict_nocarrier);
5711 	array[DEVCONF_ACCEPT_UNTRACKED_NA] =
5712 		READ_ONCE(cnf->accept_untracked_na);
5713 	array[DEVCONF_ACCEPT_RA_MIN_LFT] = READ_ONCE(cnf->accept_ra_min_lft);
5714 }
5715 
inet6_ifla6_size(void)5716 static inline size_t inet6_ifla6_size(void)
5717 {
5718 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
5719 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
5720 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
5721 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
5722 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
5723 	     + nla_total_size(sizeof(struct in6_addr)) /* IFLA_INET6_TOKEN */
5724 	     + nla_total_size(1) /* IFLA_INET6_ADDR_GEN_MODE */
5725 	     + nla_total_size(4) /* IFLA_INET6_RA_MTU */
5726 	     + 0;
5727 }
5728 
inet6_if_nlmsg_size(void)5729 static inline size_t inet6_if_nlmsg_size(void)
5730 {
5731 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
5732 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
5733 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
5734 	       + nla_total_size(4) /* IFLA_MTU */
5735 	       + nla_total_size(4) /* IFLA_LINK */
5736 	       + nla_total_size(1) /* IFLA_OPERSTATE */
5737 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
5738 }
5739 
__snmp6_fill_statsdev(u64 * stats,atomic_long_t * mib,int bytes)5740 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
5741 					int bytes)
5742 {
5743 	int i;
5744 	int pad = bytes - sizeof(u64) * ICMP6_MIB_MAX;
5745 	BUG_ON(pad < 0);
5746 
5747 	/* Use put_unaligned() because stats may not be aligned for u64. */
5748 	put_unaligned(ICMP6_MIB_MAX, &stats[0]);
5749 	for (i = 1; i < ICMP6_MIB_MAX; i++)
5750 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
5751 
5752 	memset(&stats[ICMP6_MIB_MAX], 0, pad);
5753 }
5754 
__snmp6_fill_stats64(u64 * stats,void __percpu * mib,int bytes,size_t syncpoff)5755 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
5756 					int bytes, size_t syncpoff)
5757 {
5758 	int i, c;
5759 	u64 buff[IPSTATS_MIB_MAX];
5760 	int pad = bytes - sizeof(u64) * IPSTATS_MIB_MAX;
5761 
5762 	BUG_ON(pad < 0);
5763 
5764 	memset(buff, 0, sizeof(buff));
5765 	buff[0] = IPSTATS_MIB_MAX;
5766 
5767 	for_each_possible_cpu(c) {
5768 		for (i = 1; i < IPSTATS_MIB_MAX; i++)
5769 			buff[i] += snmp_get_cpu_field64(mib, c, i, syncpoff);
5770 	}
5771 
5772 	memcpy(stats, buff, IPSTATS_MIB_MAX * sizeof(u64));
5773 	memset(&stats[IPSTATS_MIB_MAX], 0, pad);
5774 }
5775 
snmp6_fill_stats(u64 * stats,struct inet6_dev * idev,int attrtype,int bytes)5776 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
5777 			     int bytes)
5778 {
5779 	switch (attrtype) {
5780 	case IFLA_INET6_STATS:
5781 		__snmp6_fill_stats64(stats, idev->stats.ipv6, bytes,
5782 				     offsetof(struct ipstats_mib, syncp));
5783 		break;
5784 	case IFLA_INET6_ICMP6STATS:
5785 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, bytes);
5786 		break;
5787 	}
5788 }
5789 
inet6_fill_ifla6_attrs(struct sk_buff * skb,struct inet6_dev * idev,u32 ext_filter_mask)5790 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev,
5791 				  u32 ext_filter_mask)
5792 {
5793 	struct ifla_cacheinfo ci;
5794 	struct nlattr *nla;
5795 	u32 ra_mtu;
5796 
5797 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, READ_ONCE(idev->if_flags)))
5798 		goto nla_put_failure;
5799 	ci.max_reasm_len = IPV6_MAXPLEN;
5800 	ci.tstamp = cstamp_delta(READ_ONCE(idev->tstamp));
5801 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
5802 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
5803 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
5804 		goto nla_put_failure;
5805 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
5806 	if (!nla)
5807 		goto nla_put_failure;
5808 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
5809 
5810 	/* XXX - MC not implemented */
5811 
5812 	if (ext_filter_mask & RTEXT_FILTER_SKIP_STATS)
5813 		return 0;
5814 
5815 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
5816 	if (!nla)
5817 		goto nla_put_failure;
5818 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
5819 
5820 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
5821 	if (!nla)
5822 		goto nla_put_failure;
5823 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
5824 
5825 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
5826 	if (!nla)
5827 		goto nla_put_failure;
5828 	read_lock_bh(&idev->lock);
5829 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
5830 	read_unlock_bh(&idev->lock);
5831 
5832 	if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE,
5833 		       READ_ONCE(idev->cnf.addr_gen_mode)))
5834 		goto nla_put_failure;
5835 
5836 	ra_mtu = READ_ONCE(idev->ra_mtu);
5837 	if (ra_mtu && nla_put_u32(skb, IFLA_INET6_RA_MTU, ra_mtu))
5838 		goto nla_put_failure;
5839 
5840 	return 0;
5841 
5842 nla_put_failure:
5843 	return -EMSGSIZE;
5844 }
5845 
inet6_get_link_af_size(const struct net_device * dev,u32 ext_filter_mask)5846 static size_t inet6_get_link_af_size(const struct net_device *dev,
5847 				     u32 ext_filter_mask)
5848 {
5849 	if (!__in6_dev_get(dev))
5850 		return 0;
5851 
5852 	return inet6_ifla6_size();
5853 }
5854 
inet6_fill_link_af(struct sk_buff * skb,const struct net_device * dev,u32 ext_filter_mask)5855 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
5856 			      u32 ext_filter_mask)
5857 {
5858 	struct inet6_dev *idev = __in6_dev_get(dev);
5859 
5860 	if (!idev)
5861 		return -ENODATA;
5862 
5863 	if (inet6_fill_ifla6_attrs(skb, idev, ext_filter_mask) < 0)
5864 		return -EMSGSIZE;
5865 
5866 	return 0;
5867 }
5868 
inet6_set_iftoken(struct inet6_dev * idev,struct in6_addr * token,struct netlink_ext_ack * extack)5869 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token,
5870 			     struct netlink_ext_ack *extack)
5871 {
5872 	struct inet6_ifaddr *ifp;
5873 	struct net_device *dev = idev->dev;
5874 	bool clear_token, update_rs = false;
5875 	struct in6_addr ll_addr;
5876 
5877 	ASSERT_RTNL();
5878 
5879 	if (!token)
5880 		return -EINVAL;
5881 
5882 	if (dev->flags & IFF_LOOPBACK) {
5883 		NL_SET_ERR_MSG_MOD(extack, "Device is loopback");
5884 		return -EINVAL;
5885 	}
5886 
5887 	if (dev->flags & IFF_NOARP) {
5888 		NL_SET_ERR_MSG_MOD(extack,
5889 				   "Device does not do neighbour discovery");
5890 		return -EINVAL;
5891 	}
5892 
5893 	if (!ipv6_accept_ra(idev)) {
5894 		NL_SET_ERR_MSG_MOD(extack,
5895 				   "Router advertisement is disabled on device");
5896 		return -EINVAL;
5897 	}
5898 
5899 	if (READ_ONCE(idev->cnf.rtr_solicits) == 0) {
5900 		NL_SET_ERR_MSG(extack,
5901 			       "Router solicitation is disabled on device");
5902 		return -EINVAL;
5903 	}
5904 
5905 	write_lock_bh(&idev->lock);
5906 
5907 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
5908 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
5909 
5910 	write_unlock_bh(&idev->lock);
5911 
5912 	clear_token = ipv6_addr_any(token);
5913 	if (clear_token)
5914 		goto update_lft;
5915 
5916 	if (!idev->dead && (idev->if_flags & IF_READY) &&
5917 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
5918 			     IFA_F_OPTIMISTIC)) {
5919 		/* If we're not ready, then normal ifup will take care
5920 		 * of this. Otherwise, we need to request our rs here.
5921 		 */
5922 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
5923 		update_rs = true;
5924 	}
5925 
5926 update_lft:
5927 	write_lock_bh(&idev->lock);
5928 
5929 	if (update_rs) {
5930 		idev->if_flags |= IF_RS_SENT;
5931 		idev->rs_interval = rfc3315_s14_backoff_init(
5932 			READ_ONCE(idev->cnf.rtr_solicit_interval));
5933 		idev->rs_probes = 1;
5934 		addrconf_mod_rs_timer(idev, idev->rs_interval);
5935 	}
5936 
5937 	/* Well, that's kinda nasty ... */
5938 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
5939 		spin_lock(&ifp->lock);
5940 		if (ifp->tokenized) {
5941 			ifp->valid_lft = 0;
5942 			ifp->prefered_lft = 0;
5943 		}
5944 		spin_unlock(&ifp->lock);
5945 	}
5946 
5947 	write_unlock_bh(&idev->lock);
5948 	inet6_ifinfo_notify(RTM_NEWLINK, idev);
5949 	addrconf_verify_rtnl(dev_net(dev));
5950 	return 0;
5951 }
5952 
5953 static const struct nla_policy inet6_af_policy[IFLA_INET6_MAX + 1] = {
5954 	[IFLA_INET6_ADDR_GEN_MODE]	= { .type = NLA_U8 },
5955 	[IFLA_INET6_TOKEN]		= { .len = sizeof(struct in6_addr) },
5956 	[IFLA_INET6_RA_MTU]		= { .type = NLA_REJECT,
5957 					    .reject_message =
5958 						"IFLA_INET6_RA_MTU can not be set" },
5959 };
5960 
check_addr_gen_mode(int mode)5961 static int check_addr_gen_mode(int mode)
5962 {
5963 	if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
5964 	    mode != IN6_ADDR_GEN_MODE_NONE &&
5965 	    mode != IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5966 	    mode != IN6_ADDR_GEN_MODE_RANDOM)
5967 		return -EINVAL;
5968 	return 1;
5969 }
5970 
check_stable_privacy(struct inet6_dev * idev,struct net * net,int mode)5971 static int check_stable_privacy(struct inet6_dev *idev, struct net *net,
5972 				int mode)
5973 {
5974 	if (mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5975 	    !idev->cnf.stable_secret.initialized &&
5976 	    !net->ipv6.devconf_dflt->stable_secret.initialized)
5977 		return -EINVAL;
5978 	return 1;
5979 }
5980 
inet6_validate_link_af(const struct net_device * dev,const struct nlattr * nla,struct netlink_ext_ack * extack)5981 static int inet6_validate_link_af(const struct net_device *dev,
5982 				  const struct nlattr *nla,
5983 				  struct netlink_ext_ack *extack)
5984 {
5985 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5986 	struct inet6_dev *idev = NULL;
5987 	int err;
5988 
5989 	if (dev) {
5990 		idev = __in6_dev_get(dev);
5991 		if (!idev)
5992 			return -EAFNOSUPPORT;
5993 	}
5994 
5995 	err = nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla,
5996 					  inet6_af_policy, extack);
5997 	if (err)
5998 		return err;
5999 
6000 	if (!tb[IFLA_INET6_TOKEN] && !tb[IFLA_INET6_ADDR_GEN_MODE])
6001 		return -EINVAL;
6002 
6003 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
6004 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
6005 
6006 		if (check_addr_gen_mode(mode) < 0)
6007 			return -EINVAL;
6008 		if (dev && check_stable_privacy(idev, dev_net(dev), mode) < 0)
6009 			return -EINVAL;
6010 	}
6011 
6012 	return 0;
6013 }
6014 
inet6_set_link_af(struct net_device * dev,const struct nlattr * nla,struct netlink_ext_ack * extack)6015 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla,
6016 			     struct netlink_ext_ack *extack)
6017 {
6018 	struct inet6_dev *idev = __in6_dev_get(dev);
6019 	struct nlattr *tb[IFLA_INET6_MAX + 1];
6020 	int err;
6021 
6022 	if (!idev)
6023 		return -EAFNOSUPPORT;
6024 
6025 	if (nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla, NULL, NULL) < 0)
6026 		return -EINVAL;
6027 
6028 	if (tb[IFLA_INET6_TOKEN]) {
6029 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]),
6030 					extack);
6031 		if (err)
6032 			return err;
6033 	}
6034 
6035 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
6036 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
6037 
6038 		WRITE_ONCE(idev->cnf.addr_gen_mode, mode);
6039 	}
6040 
6041 	return 0;
6042 }
6043 
inet6_fill_ifinfo(struct sk_buff * skb,struct inet6_dev * idev,u32 portid,u32 seq,int event,unsigned int flags)6044 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
6045 			     u32 portid, u32 seq, int event, unsigned int flags)
6046 {
6047 	struct net_device *dev = idev->dev;
6048 	struct ifinfomsg *hdr;
6049 	struct nlmsghdr *nlh;
6050 	int ifindex, iflink;
6051 	void *protoinfo;
6052 
6053 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
6054 	if (!nlh)
6055 		return -EMSGSIZE;
6056 
6057 	hdr = nlmsg_data(nlh);
6058 	hdr->ifi_family = AF_INET6;
6059 	hdr->__ifi_pad = 0;
6060 	hdr->ifi_type = dev->type;
6061 	ifindex = READ_ONCE(dev->ifindex);
6062 	hdr->ifi_index = ifindex;
6063 	hdr->ifi_flags = dev_get_flags(dev);
6064 	hdr->ifi_change = 0;
6065 
6066 	iflink = dev_get_iflink(dev);
6067 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
6068 	    (dev->addr_len &&
6069 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
6070 	    nla_put_u32(skb, IFLA_MTU, READ_ONCE(dev->mtu)) ||
6071 	    (ifindex != iflink &&
6072 	     nla_put_u32(skb, IFLA_LINK, iflink)) ||
6073 	    nla_put_u8(skb, IFLA_OPERSTATE,
6074 		       netif_running(dev) ? READ_ONCE(dev->operstate) : IF_OPER_DOWN))
6075 		goto nla_put_failure;
6076 	protoinfo = nla_nest_start_noflag(skb, IFLA_PROTINFO);
6077 	if (!protoinfo)
6078 		goto nla_put_failure;
6079 
6080 	if (inet6_fill_ifla6_attrs(skb, idev, 0) < 0)
6081 		goto nla_put_failure;
6082 
6083 	nla_nest_end(skb, protoinfo);
6084 	nlmsg_end(skb, nlh);
6085 	return 0;
6086 
6087 nla_put_failure:
6088 	nlmsg_cancel(skb, nlh);
6089 	return -EMSGSIZE;
6090 }
6091 
inet6_valid_dump_ifinfo(const struct nlmsghdr * nlh,struct netlink_ext_ack * extack)6092 static int inet6_valid_dump_ifinfo(const struct nlmsghdr *nlh,
6093 				   struct netlink_ext_ack *extack)
6094 {
6095 	struct ifinfomsg *ifm;
6096 
6097 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
6098 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for link dump request");
6099 		return -EINVAL;
6100 	}
6101 
6102 	if (nlmsg_attrlen(nlh, sizeof(*ifm))) {
6103 		NL_SET_ERR_MSG_MOD(extack, "Invalid data after header");
6104 		return -EINVAL;
6105 	}
6106 
6107 	ifm = nlmsg_data(nlh);
6108 	if (ifm->__ifi_pad || ifm->ifi_type || ifm->ifi_flags ||
6109 	    ifm->ifi_change || ifm->ifi_index) {
6110 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for dump request");
6111 		return -EINVAL;
6112 	}
6113 
6114 	return 0;
6115 }
6116 
inet6_dump_ifinfo(struct sk_buff * skb,struct netlink_callback * cb)6117 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
6118 {
6119 	struct net *net = sock_net(skb->sk);
6120 	struct {
6121 		unsigned long ifindex;
6122 	} *ctx = (void *)cb->ctx;
6123 	struct net_device *dev;
6124 	struct inet6_dev *idev;
6125 	int err;
6126 
6127 	/* only requests using strict checking can pass data to
6128 	 * influence the dump
6129 	 */
6130 	if (cb->strict_check) {
6131 		err = inet6_valid_dump_ifinfo(cb->nlh, cb->extack);
6132 
6133 		if (err < 0)
6134 			return err;
6135 	}
6136 
6137 	err = 0;
6138 	rcu_read_lock();
6139 	for_each_netdev_dump(net, dev, ctx->ifindex) {
6140 		idev = __in6_dev_get(dev);
6141 		if (!idev)
6142 			continue;
6143 		err = inet6_fill_ifinfo(skb, idev,
6144 					NETLINK_CB(cb->skb).portid,
6145 					cb->nlh->nlmsg_seq,
6146 					RTM_NEWLINK, NLM_F_MULTI);
6147 		if (err < 0)
6148 			break;
6149 	}
6150 	rcu_read_unlock();
6151 
6152 	return err;
6153 }
6154 
inet6_ifinfo_notify(int event,struct inet6_dev * idev)6155 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
6156 {
6157 	struct sk_buff *skb;
6158 	struct net *net = dev_net(idev->dev);
6159 	int err = -ENOBUFS;
6160 
6161 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
6162 	if (!skb)
6163 		goto errout;
6164 
6165 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
6166 	if (err < 0) {
6167 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
6168 		WARN_ON(err == -EMSGSIZE);
6169 		kfree_skb(skb);
6170 		goto errout;
6171 	}
6172 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
6173 	return;
6174 errout:
6175 	rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
6176 }
6177 
inet6_prefix_nlmsg_size(void)6178 static inline size_t inet6_prefix_nlmsg_size(void)
6179 {
6180 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
6181 	       + nla_total_size(sizeof(struct in6_addr))
6182 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
6183 }
6184 
inet6_fill_prefix(struct sk_buff * skb,struct inet6_dev * idev,struct prefix_info * pinfo,u32 portid,u32 seq,int event,unsigned int flags)6185 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
6186 			     struct prefix_info *pinfo, u32 portid, u32 seq,
6187 			     int event, unsigned int flags)
6188 {
6189 	struct prefixmsg *pmsg;
6190 	struct nlmsghdr *nlh;
6191 	struct prefix_cacheinfo	ci;
6192 
6193 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
6194 	if (!nlh)
6195 		return -EMSGSIZE;
6196 
6197 	pmsg = nlmsg_data(nlh);
6198 	pmsg->prefix_family = AF_INET6;
6199 	pmsg->prefix_pad1 = 0;
6200 	pmsg->prefix_pad2 = 0;
6201 	pmsg->prefix_ifindex = idev->dev->ifindex;
6202 	pmsg->prefix_len = pinfo->prefix_len;
6203 	pmsg->prefix_type = pinfo->type;
6204 	pmsg->prefix_pad3 = 0;
6205 	pmsg->prefix_flags = pinfo->flags;
6206 
6207 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
6208 		goto nla_put_failure;
6209 	ci.preferred_time = ntohl(pinfo->prefered);
6210 	ci.valid_time = ntohl(pinfo->valid);
6211 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
6212 		goto nla_put_failure;
6213 	nlmsg_end(skb, nlh);
6214 	return 0;
6215 
6216 nla_put_failure:
6217 	nlmsg_cancel(skb, nlh);
6218 	return -EMSGSIZE;
6219 }
6220 
inet6_prefix_notify(int event,struct inet6_dev * idev,struct prefix_info * pinfo)6221 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
6222 			 struct prefix_info *pinfo)
6223 {
6224 	struct sk_buff *skb;
6225 	struct net *net = dev_net(idev->dev);
6226 	int err = -ENOBUFS;
6227 
6228 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
6229 	if (!skb)
6230 		goto errout;
6231 
6232 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
6233 	if (err < 0) {
6234 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
6235 		WARN_ON(err == -EMSGSIZE);
6236 		kfree_skb(skb);
6237 		goto errout;
6238 	}
6239 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
6240 	return;
6241 errout:
6242 	rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
6243 }
6244 
__ipv6_ifa_notify(int event,struct inet6_ifaddr * ifp)6245 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
6246 {
6247 	struct net *net = dev_net(ifp->idev->dev);
6248 
6249 	if (event)
6250 		ASSERT_RTNL();
6251 
6252 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
6253 
6254 	switch (event) {
6255 	case RTM_NEWADDR:
6256 		/*
6257 		 * If the address was optimistic we inserted the route at the
6258 		 * start of our DAD process, so we don't need to do it again.
6259 		 * If the device was taken down in the middle of the DAD
6260 		 * cycle there is a race where we could get here without a
6261 		 * host route, so nothing to insert. That will be fixed when
6262 		 * the device is brought up.
6263 		 */
6264 		if (ifp->rt && !rcu_access_pointer(ifp->rt->fib6_node)) {
6265 			ip6_ins_rt(net, ifp->rt);
6266 		} else if (!ifp->rt && (ifp->idev->dev->flags & IFF_UP)) {
6267 			pr_warn("BUG: Address %pI6c on device %s is missing its host route.\n",
6268 				&ifp->addr, ifp->idev->dev->name);
6269 		}
6270 
6271 		if (ifp->idev->cnf.forwarding)
6272 			addrconf_join_anycast(ifp);
6273 		if (!ipv6_addr_any(&ifp->peer_addr))
6274 			addrconf_prefix_route(&ifp->peer_addr, 128,
6275 					      ifp->rt_priority, ifp->idev->dev,
6276 					      0, 0, GFP_ATOMIC);
6277 		break;
6278 	case RTM_DELADDR:
6279 		if (ifp->idev->cnf.forwarding)
6280 			addrconf_leave_anycast(ifp);
6281 		addrconf_leave_solict(ifp->idev, &ifp->addr);
6282 		if (!ipv6_addr_any(&ifp->peer_addr)) {
6283 			struct fib6_info *rt;
6284 
6285 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
6286 						       ifp->idev->dev, 0, 0,
6287 						       false);
6288 			if (rt)
6289 				ip6_del_rt(net, rt, false);
6290 		}
6291 		if (ifp->rt) {
6292 			ip6_del_rt(net, ifp->rt, false);
6293 			ifp->rt = NULL;
6294 		}
6295 		rt_genid_bump_ipv6(net);
6296 		break;
6297 	}
6298 	atomic_inc(&net->ipv6.dev_addr_genid);
6299 }
6300 
ipv6_ifa_notify(int event,struct inet6_ifaddr * ifp)6301 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
6302 {
6303 	if (likely(ifp->idev->dead == 0))
6304 		__ipv6_ifa_notify(event, ifp);
6305 }
6306 
6307 #ifdef CONFIG_SYSCTL
6308 
addrconf_sysctl_forward(const struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)6309 static int addrconf_sysctl_forward(const struct ctl_table *ctl, int write,
6310 		void *buffer, size_t *lenp, loff_t *ppos)
6311 {
6312 	int *valp = ctl->data;
6313 	int val = *valp;
6314 	loff_t pos = *ppos;
6315 	struct ctl_table lctl;
6316 	int ret;
6317 
6318 	/*
6319 	 * ctl->data points to idev->cnf.forwarding, we should
6320 	 * not modify it until we get the rtnl lock.
6321 	 */
6322 	lctl = *ctl;
6323 	lctl.data = &val;
6324 
6325 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6326 
6327 	if (write)
6328 		ret = addrconf_fixup_forwarding(ctl, valp, val);
6329 	if (ret)
6330 		*ppos = pos;
6331 	return ret;
6332 }
6333 
addrconf_sysctl_mtu(const struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)6334 static int addrconf_sysctl_mtu(const struct ctl_table *ctl, int write,
6335 		void *buffer, size_t *lenp, loff_t *ppos)
6336 {
6337 	struct inet6_dev *idev = ctl->extra1;
6338 	int min_mtu = IPV6_MIN_MTU;
6339 	struct ctl_table lctl;
6340 
6341 	lctl = *ctl;
6342 	lctl.extra1 = &min_mtu;
6343 	lctl.extra2 = idev ? &idev->dev->mtu : NULL;
6344 
6345 	return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
6346 }
6347 
dev_disable_change(struct inet6_dev * idev)6348 static void dev_disable_change(struct inet6_dev *idev)
6349 {
6350 	struct netdev_notifier_info info;
6351 
6352 	if (!idev || !idev->dev)
6353 		return;
6354 
6355 	netdev_notifier_info_init(&info, idev->dev);
6356 	if (idev->cnf.disable_ipv6)
6357 		addrconf_notify(NULL, NETDEV_DOWN, &info);
6358 	else
6359 		addrconf_notify(NULL, NETDEV_UP, &info);
6360 }
6361 
addrconf_disable_change(struct net * net,__s32 newf)6362 static void addrconf_disable_change(struct net *net, __s32 newf)
6363 {
6364 	struct net_device *dev;
6365 	struct inet6_dev *idev;
6366 
6367 	for_each_netdev(net, dev) {
6368 		idev = __in6_dev_get_rtnl_net(dev);
6369 		if (idev) {
6370 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
6371 
6372 			WRITE_ONCE(idev->cnf.disable_ipv6, newf);
6373 			if (changed)
6374 				dev_disable_change(idev);
6375 		}
6376 	}
6377 }
6378 
addrconf_disable_ipv6(const struct ctl_table * table,int * p,int newf)6379 static int addrconf_disable_ipv6(const struct ctl_table *table, int *p, int newf)
6380 {
6381 	struct net *net = (struct net *)table->extra2;
6382 	int old;
6383 
6384 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
6385 		WRITE_ONCE(*p, newf);
6386 		return 0;
6387 	}
6388 
6389 	if (!rtnl_net_trylock(net))
6390 		return restart_syscall();
6391 
6392 	old = *p;
6393 	WRITE_ONCE(*p, newf);
6394 
6395 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
6396 		WRITE_ONCE(net->ipv6.devconf_dflt->disable_ipv6, newf);
6397 		addrconf_disable_change(net, newf);
6398 	} else if ((!newf) ^ (!old)) {
6399 		dev_disable_change((struct inet6_dev *)table->extra1);
6400 	}
6401 
6402 	rtnl_net_unlock(net);
6403 	return 0;
6404 }
6405 
addrconf_sysctl_disable(const struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)6406 static int addrconf_sysctl_disable(const struct ctl_table *ctl, int write,
6407 		void *buffer, size_t *lenp, loff_t *ppos)
6408 {
6409 	int *valp = ctl->data;
6410 	int val = *valp;
6411 	loff_t pos = *ppos;
6412 	struct ctl_table lctl;
6413 	int ret;
6414 
6415 	/*
6416 	 * ctl->data points to idev->cnf.disable_ipv6, we should
6417 	 * not modify it until we get the rtnl lock.
6418 	 */
6419 	lctl = *ctl;
6420 	lctl.data = &val;
6421 
6422 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6423 
6424 	if (write)
6425 		ret = addrconf_disable_ipv6(ctl, valp, val);
6426 	if (ret)
6427 		*ppos = pos;
6428 	return ret;
6429 }
6430 
addrconf_sysctl_proxy_ndp(const struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)6431 static int addrconf_sysctl_proxy_ndp(const struct ctl_table *ctl, int write,
6432 		void *buffer, size_t *lenp, loff_t *ppos)
6433 {
6434 	int *valp = ctl->data;
6435 	int ret;
6436 	int old, new;
6437 
6438 	old = *valp;
6439 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
6440 	new = *valp;
6441 
6442 	if (write && old != new) {
6443 		struct net *net = ctl->extra2;
6444 
6445 		if (!rtnl_net_trylock(net))
6446 			return restart_syscall();
6447 
6448 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp) {
6449 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6450 						     NETCONFA_PROXY_NEIGH,
6451 						     NETCONFA_IFINDEX_DEFAULT,
6452 						     net->ipv6.devconf_dflt);
6453 		} else if (valp == &net->ipv6.devconf_all->proxy_ndp) {
6454 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6455 						     NETCONFA_PROXY_NEIGH,
6456 						     NETCONFA_IFINDEX_ALL,
6457 						     net->ipv6.devconf_all);
6458 		} else {
6459 			struct inet6_dev *idev = ctl->extra1;
6460 
6461 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6462 						     NETCONFA_PROXY_NEIGH,
6463 						     idev->dev->ifindex,
6464 						     &idev->cnf);
6465 		}
6466 		rtnl_net_unlock(net);
6467 	}
6468 
6469 	return ret;
6470 }
6471 
addrconf_sysctl_addr_gen_mode(const struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)6472 static int addrconf_sysctl_addr_gen_mode(const struct ctl_table *ctl, int write,
6473 					 void *buffer, size_t *lenp,
6474 					 loff_t *ppos)
6475 {
6476 	int ret = 0;
6477 	u32 new_val;
6478 	struct inet6_dev *idev = (struct inet6_dev *)ctl->extra1;
6479 	struct net *net = (struct net *)ctl->extra2;
6480 	struct ctl_table tmp = {
6481 		.data = &new_val,
6482 		.maxlen = sizeof(new_val),
6483 		.mode = ctl->mode,
6484 	};
6485 
6486 	if (!rtnl_net_trylock(net))
6487 		return restart_syscall();
6488 
6489 	new_val = *((u32 *)ctl->data);
6490 
6491 	ret = proc_douintvec(&tmp, write, buffer, lenp, ppos);
6492 	if (ret != 0)
6493 		goto out;
6494 
6495 	if (write) {
6496 		if (check_addr_gen_mode(new_val) < 0) {
6497 			ret = -EINVAL;
6498 			goto out;
6499 		}
6500 
6501 		if (idev) {
6502 			if (check_stable_privacy(idev, net, new_val) < 0) {
6503 				ret = -EINVAL;
6504 				goto out;
6505 			}
6506 
6507 			if (idev->cnf.addr_gen_mode != new_val) {
6508 				WRITE_ONCE(idev->cnf.addr_gen_mode, new_val);
6509 				addrconf_init_auto_addrs(idev->dev);
6510 			}
6511 		} else if (&net->ipv6.devconf_all->addr_gen_mode == ctl->data) {
6512 			struct net_device *dev;
6513 
6514 			WRITE_ONCE(net->ipv6.devconf_dflt->addr_gen_mode, new_val);
6515 			for_each_netdev(net, dev) {
6516 				idev = __in6_dev_get_rtnl_net(dev);
6517 				if (idev &&
6518 				    idev->cnf.addr_gen_mode != new_val) {
6519 					WRITE_ONCE(idev->cnf.addr_gen_mode,
6520 						  new_val);
6521 					addrconf_init_auto_addrs(idev->dev);
6522 				}
6523 			}
6524 		}
6525 
6526 		WRITE_ONCE(*((u32 *)ctl->data), new_val);
6527 	}
6528 
6529 out:
6530 	rtnl_net_unlock(net);
6531 
6532 	return ret;
6533 }
6534 
addrconf_sysctl_stable_secret(const struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)6535 static int addrconf_sysctl_stable_secret(const struct ctl_table *ctl, int write,
6536 					 void *buffer, size_t *lenp,
6537 					 loff_t *ppos)
6538 {
6539 	int err;
6540 	struct in6_addr addr;
6541 	char str[IPV6_MAX_STRLEN];
6542 	struct ctl_table lctl = *ctl;
6543 	struct net *net = ctl->extra2;
6544 	struct ipv6_stable_secret *secret = ctl->data;
6545 
6546 	if (&net->ipv6.devconf_all->stable_secret == ctl->data)
6547 		return -EIO;
6548 
6549 	lctl.maxlen = IPV6_MAX_STRLEN;
6550 	lctl.data = str;
6551 
6552 	if (!rtnl_net_trylock(net))
6553 		return restart_syscall();
6554 
6555 	if (!write && !secret->initialized) {
6556 		err = -EIO;
6557 		goto out;
6558 	}
6559 
6560 	err = snprintf(str, sizeof(str), "%pI6", &secret->secret);
6561 	if (err >= sizeof(str)) {
6562 		err = -EIO;
6563 		goto out;
6564 	}
6565 
6566 	err = proc_dostring(&lctl, write, buffer, lenp, ppos);
6567 	if (err || !write)
6568 		goto out;
6569 
6570 	if (in6_pton(str, -1, addr.in6_u.u6_addr8, -1, NULL) != 1) {
6571 		err = -EIO;
6572 		goto out;
6573 	}
6574 
6575 	secret->initialized = true;
6576 	secret->secret = addr;
6577 
6578 	if (&net->ipv6.devconf_dflt->stable_secret == ctl->data) {
6579 		struct net_device *dev;
6580 
6581 		for_each_netdev(net, dev) {
6582 			struct inet6_dev *idev = __in6_dev_get_rtnl_net(dev);
6583 
6584 			if (idev) {
6585 				WRITE_ONCE(idev->cnf.addr_gen_mode,
6586 					   IN6_ADDR_GEN_MODE_STABLE_PRIVACY);
6587 			}
6588 		}
6589 	} else {
6590 		struct inet6_dev *idev = ctl->extra1;
6591 
6592 		WRITE_ONCE(idev->cnf.addr_gen_mode,
6593 			   IN6_ADDR_GEN_MODE_STABLE_PRIVACY);
6594 	}
6595 
6596 out:
6597 	rtnl_net_unlock(net);
6598 
6599 	return err;
6600 }
6601 
6602 static
addrconf_sysctl_ignore_routes_with_linkdown(const struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)6603 int addrconf_sysctl_ignore_routes_with_linkdown(const struct ctl_table *ctl,
6604 						int write, void *buffer,
6605 						size_t *lenp,
6606 						loff_t *ppos)
6607 {
6608 	int *valp = ctl->data;
6609 	int val = *valp;
6610 	loff_t pos = *ppos;
6611 	struct ctl_table lctl;
6612 	int ret;
6613 
6614 	/* ctl->data points to idev->cnf.ignore_routes_when_linkdown
6615 	 * we should not modify it until we get the rtnl lock.
6616 	 */
6617 	lctl = *ctl;
6618 	lctl.data = &val;
6619 
6620 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6621 
6622 	if (write)
6623 		ret = addrconf_fixup_linkdown(ctl, valp, val);
6624 	if (ret)
6625 		*ppos = pos;
6626 	return ret;
6627 }
6628 
6629 static
addrconf_set_nopolicy(struct rt6_info * rt,int action)6630 void addrconf_set_nopolicy(struct rt6_info *rt, int action)
6631 {
6632 	if (rt) {
6633 		if (action)
6634 			rt->dst.flags |= DST_NOPOLICY;
6635 		else
6636 			rt->dst.flags &= ~DST_NOPOLICY;
6637 	}
6638 }
6639 
6640 static
addrconf_disable_policy_idev(struct inet6_dev * idev,int val)6641 void addrconf_disable_policy_idev(struct inet6_dev *idev, int val)
6642 {
6643 	struct inet6_ifaddr *ifa;
6644 
6645 	read_lock_bh(&idev->lock);
6646 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
6647 		spin_lock(&ifa->lock);
6648 		if (ifa->rt) {
6649 			/* host routes only use builtin fib6_nh */
6650 			struct fib6_nh *nh = ifa->rt->fib6_nh;
6651 			int cpu;
6652 
6653 			rcu_read_lock();
6654 			ifa->rt->dst_nopolicy = val ? true : false;
6655 			if (nh->rt6i_pcpu) {
6656 				for_each_possible_cpu(cpu) {
6657 					struct rt6_info **rtp;
6658 
6659 					rtp = per_cpu_ptr(nh->rt6i_pcpu, cpu);
6660 					addrconf_set_nopolicy(*rtp, val);
6661 				}
6662 			}
6663 			rcu_read_unlock();
6664 		}
6665 		spin_unlock(&ifa->lock);
6666 	}
6667 	read_unlock_bh(&idev->lock);
6668 }
6669 
6670 static
addrconf_disable_policy(const struct ctl_table * ctl,int * valp,int val)6671 int addrconf_disable_policy(const struct ctl_table *ctl, int *valp, int val)
6672 {
6673 	struct net *net = (struct net *)ctl->extra2;
6674 	struct inet6_dev *idev;
6675 
6676 	if (valp == &net->ipv6.devconf_dflt->disable_policy) {
6677 		WRITE_ONCE(*valp, val);
6678 		return 0;
6679 	}
6680 
6681 	if (!rtnl_net_trylock(net))
6682 		return restart_syscall();
6683 
6684 	WRITE_ONCE(*valp, val);
6685 
6686 	if (valp == &net->ipv6.devconf_all->disable_policy)  {
6687 		struct net_device *dev;
6688 
6689 		for_each_netdev(net, dev) {
6690 			idev = __in6_dev_get_rtnl_net(dev);
6691 			if (idev)
6692 				addrconf_disable_policy_idev(idev, val);
6693 		}
6694 	} else {
6695 		idev = (struct inet6_dev *)ctl->extra1;
6696 		addrconf_disable_policy_idev(idev, val);
6697 	}
6698 
6699 	rtnl_net_unlock(net);
6700 	return 0;
6701 }
6702 
addrconf_sysctl_disable_policy(const struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)6703 static int addrconf_sysctl_disable_policy(const struct ctl_table *ctl, int write,
6704 				   void *buffer, size_t *lenp, loff_t *ppos)
6705 {
6706 	int *valp = ctl->data;
6707 	int val = *valp;
6708 	loff_t pos = *ppos;
6709 	struct ctl_table lctl;
6710 	int ret;
6711 
6712 	lctl = *ctl;
6713 	lctl.data = &val;
6714 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6715 
6716 	if (write && (*valp != val))
6717 		ret = addrconf_disable_policy(ctl, valp, val);
6718 
6719 	if (ret)
6720 		*ppos = pos;
6721 
6722 	return ret;
6723 }
6724 
6725 static int minus_one = -1;
6726 static const int two_five_five = 255;
6727 static u32 ioam6_if_id_max = U16_MAX;
6728 
6729 static const struct ctl_table addrconf_sysctl[] = {
6730 	{
6731 		.procname	= "forwarding",
6732 		.data		= &ipv6_devconf.forwarding,
6733 		.maxlen		= sizeof(int),
6734 		.mode		= 0644,
6735 		.proc_handler	= addrconf_sysctl_forward,
6736 	},
6737 	{
6738 		.procname	= "hop_limit",
6739 		.data		= &ipv6_devconf.hop_limit,
6740 		.maxlen		= sizeof(int),
6741 		.mode		= 0644,
6742 		.proc_handler	= proc_dointvec_minmax,
6743 		.extra1		= (void *)SYSCTL_ONE,
6744 		.extra2		= (void *)&two_five_five,
6745 	},
6746 	{
6747 		.procname	= "mtu",
6748 		.data		= &ipv6_devconf.mtu6,
6749 		.maxlen		= sizeof(int),
6750 		.mode		= 0644,
6751 		.proc_handler	= addrconf_sysctl_mtu,
6752 	},
6753 	{
6754 		.procname	= "accept_ra",
6755 		.data		= &ipv6_devconf.accept_ra,
6756 		.maxlen		= sizeof(int),
6757 		.mode		= 0644,
6758 		.proc_handler	= proc_dointvec,
6759 	},
6760 	{
6761 		.procname	= "accept_redirects",
6762 		.data		= &ipv6_devconf.accept_redirects,
6763 		.maxlen		= sizeof(int),
6764 		.mode		= 0644,
6765 		.proc_handler	= proc_dointvec,
6766 	},
6767 	{
6768 		.procname	= "autoconf",
6769 		.data		= &ipv6_devconf.autoconf,
6770 		.maxlen		= sizeof(int),
6771 		.mode		= 0644,
6772 		.proc_handler	= proc_dointvec,
6773 	},
6774 	{
6775 		.procname	= "dad_transmits",
6776 		.data		= &ipv6_devconf.dad_transmits,
6777 		.maxlen		= sizeof(int),
6778 		.mode		= 0644,
6779 		.proc_handler	= proc_dointvec,
6780 	},
6781 	{
6782 		.procname	= "router_solicitations",
6783 		.data		= &ipv6_devconf.rtr_solicits,
6784 		.maxlen		= sizeof(int),
6785 		.mode		= 0644,
6786 		.proc_handler	= proc_dointvec_minmax,
6787 		.extra1		= &minus_one,
6788 	},
6789 	{
6790 		.procname	= "router_solicitation_interval",
6791 		.data		= &ipv6_devconf.rtr_solicit_interval,
6792 		.maxlen		= sizeof(int),
6793 		.mode		= 0644,
6794 		.proc_handler	= proc_dointvec_jiffies,
6795 	},
6796 	{
6797 		.procname	= "router_solicitation_max_interval",
6798 		.data		= &ipv6_devconf.rtr_solicit_max_interval,
6799 		.maxlen		= sizeof(int),
6800 		.mode		= 0644,
6801 		.proc_handler	= proc_dointvec_jiffies,
6802 	},
6803 	{
6804 		.procname	= "router_solicitation_delay",
6805 		.data		= &ipv6_devconf.rtr_solicit_delay,
6806 		.maxlen		= sizeof(int),
6807 		.mode		= 0644,
6808 		.proc_handler	= proc_dointvec_jiffies,
6809 	},
6810 	{
6811 		.procname	= "force_mld_version",
6812 		.data		= &ipv6_devconf.force_mld_version,
6813 		.maxlen		= sizeof(int),
6814 		.mode		= 0644,
6815 		.proc_handler	= proc_dointvec,
6816 	},
6817 	{
6818 		.procname	= "mldv1_unsolicited_report_interval",
6819 		.data		=
6820 			&ipv6_devconf.mldv1_unsolicited_report_interval,
6821 		.maxlen		= sizeof(int),
6822 		.mode		= 0644,
6823 		.proc_handler	= proc_dointvec_ms_jiffies,
6824 	},
6825 	{
6826 		.procname	= "mldv2_unsolicited_report_interval",
6827 		.data		=
6828 			&ipv6_devconf.mldv2_unsolicited_report_interval,
6829 		.maxlen		= sizeof(int),
6830 		.mode		= 0644,
6831 		.proc_handler	= proc_dointvec_ms_jiffies,
6832 	},
6833 	{
6834 		.procname	= "use_tempaddr",
6835 		.data		= &ipv6_devconf.use_tempaddr,
6836 		.maxlen		= sizeof(int),
6837 		.mode		= 0644,
6838 		.proc_handler	= proc_dointvec,
6839 	},
6840 	{
6841 		.procname	= "temp_valid_lft",
6842 		.data		= &ipv6_devconf.temp_valid_lft,
6843 		.maxlen		= sizeof(int),
6844 		.mode		= 0644,
6845 		.proc_handler	= proc_dointvec,
6846 	},
6847 	{
6848 		.procname	= "temp_prefered_lft",
6849 		.data		= &ipv6_devconf.temp_prefered_lft,
6850 		.maxlen		= sizeof(int),
6851 		.mode		= 0644,
6852 		.proc_handler	= proc_dointvec,
6853 	},
6854 	{
6855 		.procname       = "regen_min_advance",
6856 		.data           = &ipv6_devconf.regen_min_advance,
6857 		.maxlen         = sizeof(int),
6858 		.mode           = 0644,
6859 		.proc_handler   = proc_dointvec,
6860 	},
6861 	{
6862 		.procname	= "regen_max_retry",
6863 		.data		= &ipv6_devconf.regen_max_retry,
6864 		.maxlen		= sizeof(int),
6865 		.mode		= 0644,
6866 		.proc_handler	= proc_dointvec,
6867 	},
6868 	{
6869 		.procname	= "max_desync_factor",
6870 		.data		= &ipv6_devconf.max_desync_factor,
6871 		.maxlen		= sizeof(int),
6872 		.mode		= 0644,
6873 		.proc_handler	= proc_dointvec,
6874 	},
6875 	{
6876 		.procname	= "max_addresses",
6877 		.data		= &ipv6_devconf.max_addresses,
6878 		.maxlen		= sizeof(int),
6879 		.mode		= 0644,
6880 		.proc_handler	= proc_dointvec,
6881 	},
6882 	{
6883 		.procname	= "accept_ra_defrtr",
6884 		.data		= &ipv6_devconf.accept_ra_defrtr,
6885 		.maxlen		= sizeof(int),
6886 		.mode		= 0644,
6887 		.proc_handler	= proc_dointvec,
6888 	},
6889 	{
6890 		.procname	= "ra_defrtr_metric",
6891 		.data		= &ipv6_devconf.ra_defrtr_metric,
6892 		.maxlen		= sizeof(u32),
6893 		.mode		= 0644,
6894 		.proc_handler	= proc_douintvec_minmax,
6895 		.extra1		= (void *)SYSCTL_ONE,
6896 	},
6897 	{
6898 		.procname	= "accept_ra_min_hop_limit",
6899 		.data		= &ipv6_devconf.accept_ra_min_hop_limit,
6900 		.maxlen		= sizeof(int),
6901 		.mode		= 0644,
6902 		.proc_handler	= proc_dointvec,
6903 	},
6904 	{
6905 		.procname	= "accept_ra_min_lft",
6906 		.data		= &ipv6_devconf.accept_ra_min_lft,
6907 		.maxlen		= sizeof(int),
6908 		.mode		= 0644,
6909 		.proc_handler	= proc_dointvec,
6910 	},
6911 	{
6912 		.procname	= "accept_ra_pinfo",
6913 		.data		= &ipv6_devconf.accept_ra_pinfo,
6914 		.maxlen		= sizeof(int),
6915 		.mode		= 0644,
6916 		.proc_handler	= proc_dointvec,
6917 	},
6918 	{
6919 		.procname	= "ra_honor_pio_life",
6920 		.data		= &ipv6_devconf.ra_honor_pio_life,
6921 		.maxlen		= sizeof(u8),
6922 		.mode		= 0644,
6923 		.proc_handler	= proc_dou8vec_minmax,
6924 		.extra1		= SYSCTL_ZERO,
6925 		.extra2		= SYSCTL_ONE,
6926 	},
6927 	{
6928 		.procname	= "ra_honor_pio_pflag",
6929 		.data		= &ipv6_devconf.ra_honor_pio_pflag,
6930 		.maxlen		= sizeof(u8),
6931 		.mode		= 0644,
6932 		.proc_handler	= proc_dou8vec_minmax,
6933 		.extra1		= SYSCTL_ZERO,
6934 		.extra2		= SYSCTL_ONE,
6935 	},
6936 #ifdef CONFIG_IPV6_ROUTER_PREF
6937 	{
6938 		.procname	= "accept_ra_rtr_pref",
6939 		.data		= &ipv6_devconf.accept_ra_rtr_pref,
6940 		.maxlen		= sizeof(int),
6941 		.mode		= 0644,
6942 		.proc_handler	= proc_dointvec,
6943 	},
6944 	{
6945 		.procname	= "router_probe_interval",
6946 		.data		= &ipv6_devconf.rtr_probe_interval,
6947 		.maxlen		= sizeof(int),
6948 		.mode		= 0644,
6949 		.proc_handler	= proc_dointvec_jiffies,
6950 	},
6951 #ifdef CONFIG_IPV6_ROUTE_INFO
6952 	{
6953 		.procname	= "accept_ra_rt_info_min_plen",
6954 		.data		= &ipv6_devconf.accept_ra_rt_info_min_plen,
6955 		.maxlen		= sizeof(int),
6956 		.mode		= 0644,
6957 		.proc_handler	= proc_dointvec,
6958 	},
6959 	{
6960 		.procname	= "accept_ra_rt_info_max_plen",
6961 		.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
6962 		.maxlen		= sizeof(int),
6963 		.mode		= 0644,
6964 		.proc_handler	= proc_dointvec,
6965 	},
6966 #endif
6967 #endif
6968 	{
6969 		.procname	= "proxy_ndp",
6970 		.data		= &ipv6_devconf.proxy_ndp,
6971 		.maxlen		= sizeof(int),
6972 		.mode		= 0644,
6973 		.proc_handler	= addrconf_sysctl_proxy_ndp,
6974 	},
6975 	{
6976 		.procname	= "accept_source_route",
6977 		.data		= &ipv6_devconf.accept_source_route,
6978 		.maxlen		= sizeof(int),
6979 		.mode		= 0644,
6980 		.proc_handler	= proc_dointvec,
6981 	},
6982 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
6983 	{
6984 		.procname	= "optimistic_dad",
6985 		.data		= &ipv6_devconf.optimistic_dad,
6986 		.maxlen		= sizeof(int),
6987 		.mode		= 0644,
6988 		.proc_handler   = proc_dointvec,
6989 	},
6990 	{
6991 		.procname	= "use_optimistic",
6992 		.data		= &ipv6_devconf.use_optimistic,
6993 		.maxlen		= sizeof(int),
6994 		.mode		= 0644,
6995 		.proc_handler	= proc_dointvec,
6996 	},
6997 #endif
6998 #ifdef CONFIG_IPV6_MROUTE
6999 	{
7000 		.procname	= "mc_forwarding",
7001 		.data		= &ipv6_devconf.mc_forwarding,
7002 		.maxlen		= sizeof(int),
7003 		.mode		= 0444,
7004 		.proc_handler	= proc_dointvec,
7005 	},
7006 #endif
7007 	{
7008 		.procname	= "disable_ipv6",
7009 		.data		= &ipv6_devconf.disable_ipv6,
7010 		.maxlen		= sizeof(int),
7011 		.mode		= 0644,
7012 		.proc_handler	= addrconf_sysctl_disable,
7013 	},
7014 	{
7015 		.procname	= "accept_dad",
7016 		.data		= &ipv6_devconf.accept_dad,
7017 		.maxlen		= sizeof(int),
7018 		.mode		= 0644,
7019 		.proc_handler	= proc_dointvec,
7020 	},
7021 	{
7022 		.procname	= "force_tllao",
7023 		.data		= &ipv6_devconf.force_tllao,
7024 		.maxlen		= sizeof(int),
7025 		.mode		= 0644,
7026 		.proc_handler	= proc_dointvec
7027 	},
7028 	{
7029 		.procname	= "ndisc_notify",
7030 		.data		= &ipv6_devconf.ndisc_notify,
7031 		.maxlen		= sizeof(int),
7032 		.mode		= 0644,
7033 		.proc_handler	= proc_dointvec
7034 	},
7035 	{
7036 		.procname	= "suppress_frag_ndisc",
7037 		.data		= &ipv6_devconf.suppress_frag_ndisc,
7038 		.maxlen		= sizeof(int),
7039 		.mode		= 0644,
7040 		.proc_handler	= proc_dointvec
7041 	},
7042 	{
7043 		.procname	= "accept_ra_from_local",
7044 		.data		= &ipv6_devconf.accept_ra_from_local,
7045 		.maxlen		= sizeof(int),
7046 		.mode		= 0644,
7047 		.proc_handler	= proc_dointvec,
7048 	},
7049 	{
7050 		.procname	= "accept_ra_mtu",
7051 		.data		= &ipv6_devconf.accept_ra_mtu,
7052 		.maxlen		= sizeof(int),
7053 		.mode		= 0644,
7054 		.proc_handler	= proc_dointvec,
7055 	},
7056 	{
7057 		.procname	= "stable_secret",
7058 		.data		= &ipv6_devconf.stable_secret,
7059 		.maxlen		= IPV6_MAX_STRLEN,
7060 		.mode		= 0600,
7061 		.proc_handler	= addrconf_sysctl_stable_secret,
7062 	},
7063 	{
7064 		.procname	= "use_oif_addrs_only",
7065 		.data		= &ipv6_devconf.use_oif_addrs_only,
7066 		.maxlen		= sizeof(int),
7067 		.mode		= 0644,
7068 		.proc_handler	= proc_dointvec,
7069 	},
7070 	{
7071 		.procname	= "ignore_routes_with_linkdown",
7072 		.data		= &ipv6_devconf.ignore_routes_with_linkdown,
7073 		.maxlen		= sizeof(int),
7074 		.mode		= 0644,
7075 		.proc_handler	= addrconf_sysctl_ignore_routes_with_linkdown,
7076 	},
7077 	{
7078 		.procname	= "drop_unicast_in_l2_multicast",
7079 		.data		= &ipv6_devconf.drop_unicast_in_l2_multicast,
7080 		.maxlen		= sizeof(int),
7081 		.mode		= 0644,
7082 		.proc_handler	= proc_dointvec,
7083 	},
7084 	{
7085 		.procname	= "drop_unsolicited_na",
7086 		.data		= &ipv6_devconf.drop_unsolicited_na,
7087 		.maxlen		= sizeof(int),
7088 		.mode		= 0644,
7089 		.proc_handler	= proc_dointvec,
7090 	},
7091 	{
7092 		.procname	= "keep_addr_on_down",
7093 		.data		= &ipv6_devconf.keep_addr_on_down,
7094 		.maxlen		= sizeof(int),
7095 		.mode		= 0644,
7096 		.proc_handler	= proc_dointvec,
7097 
7098 	},
7099 	{
7100 		.procname	= "seg6_enabled",
7101 		.data		= &ipv6_devconf.seg6_enabled,
7102 		.maxlen		= sizeof(int),
7103 		.mode		= 0644,
7104 		.proc_handler	= proc_dointvec,
7105 	},
7106 #ifdef CONFIG_IPV6_SEG6_HMAC
7107 	{
7108 		.procname	= "seg6_require_hmac",
7109 		.data		= &ipv6_devconf.seg6_require_hmac,
7110 		.maxlen		= sizeof(int),
7111 		.mode		= 0644,
7112 		.proc_handler	= proc_dointvec,
7113 	},
7114 #endif
7115 	{
7116 		.procname       = "enhanced_dad",
7117 		.data           = &ipv6_devconf.enhanced_dad,
7118 		.maxlen         = sizeof(int),
7119 		.mode           = 0644,
7120 		.proc_handler   = proc_dointvec,
7121 	},
7122 	{
7123 		.procname	= "addr_gen_mode",
7124 		.data		= &ipv6_devconf.addr_gen_mode,
7125 		.maxlen		= sizeof(int),
7126 		.mode		= 0644,
7127 		.proc_handler	= addrconf_sysctl_addr_gen_mode,
7128 	},
7129 	{
7130 		.procname       = "disable_policy",
7131 		.data           = &ipv6_devconf.disable_policy,
7132 		.maxlen         = sizeof(int),
7133 		.mode           = 0644,
7134 		.proc_handler   = addrconf_sysctl_disable_policy,
7135 	},
7136 	{
7137 		.procname	= "ndisc_tclass",
7138 		.data		= &ipv6_devconf.ndisc_tclass,
7139 		.maxlen		= sizeof(int),
7140 		.mode		= 0644,
7141 		.proc_handler	= proc_dointvec_minmax,
7142 		.extra1		= (void *)SYSCTL_ZERO,
7143 		.extra2		= (void *)&two_five_five,
7144 	},
7145 	{
7146 		.procname	= "rpl_seg_enabled",
7147 		.data		= &ipv6_devconf.rpl_seg_enabled,
7148 		.maxlen		= sizeof(int),
7149 		.mode		= 0644,
7150 		.proc_handler	= proc_dointvec,
7151 	},
7152 	{
7153 		.procname	= "ioam6_enabled",
7154 		.data		= &ipv6_devconf.ioam6_enabled,
7155 		.maxlen		= sizeof(u8),
7156 		.mode		= 0644,
7157 		.proc_handler	= proc_dou8vec_minmax,
7158 		.extra1		= (void *)SYSCTL_ZERO,
7159 		.extra2		= (void *)SYSCTL_ONE,
7160 	},
7161 	{
7162 		.procname	= "ioam6_id",
7163 		.data		= &ipv6_devconf.ioam6_id,
7164 		.maxlen		= sizeof(u32),
7165 		.mode		= 0644,
7166 		.proc_handler	= proc_douintvec_minmax,
7167 		.extra1		= (void *)SYSCTL_ZERO,
7168 		.extra2		= (void *)&ioam6_if_id_max,
7169 	},
7170 	{
7171 		.procname	= "ioam6_id_wide",
7172 		.data		= &ipv6_devconf.ioam6_id_wide,
7173 		.maxlen		= sizeof(u32),
7174 		.mode		= 0644,
7175 		.proc_handler	= proc_douintvec,
7176 	},
7177 	{
7178 		.procname	= "ndisc_evict_nocarrier",
7179 		.data		= &ipv6_devconf.ndisc_evict_nocarrier,
7180 		.maxlen		= sizeof(u8),
7181 		.mode		= 0644,
7182 		.proc_handler	= proc_dou8vec_minmax,
7183 		.extra1		= (void *)SYSCTL_ZERO,
7184 		.extra2		= (void *)SYSCTL_ONE,
7185 	},
7186 	{
7187 		.procname	= "accept_untracked_na",
7188 		.data		= &ipv6_devconf.accept_untracked_na,
7189 		.maxlen		= sizeof(int),
7190 		.mode		= 0644,
7191 		.proc_handler	= proc_dointvec_minmax,
7192 		.extra1		= SYSCTL_ZERO,
7193 		.extra2		= SYSCTL_TWO,
7194 	},
7195 };
7196 
__addrconf_sysctl_register(struct net * net,char * dev_name,struct inet6_dev * idev,struct ipv6_devconf * p)7197 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
7198 		struct inet6_dev *idev, struct ipv6_devconf *p)
7199 {
7200 	size_t table_size = ARRAY_SIZE(addrconf_sysctl);
7201 	int i, ifindex;
7202 	struct ctl_table *table;
7203 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
7204 
7205 	table = kmemdup(addrconf_sysctl, sizeof(addrconf_sysctl), GFP_KERNEL_ACCOUNT);
7206 	if (!table)
7207 		goto out;
7208 
7209 	for (i = 0; i < table_size; i++) {
7210 		table[i].data += (char *)p - (char *)&ipv6_devconf;
7211 		/* If one of these is already set, then it is not safe to
7212 		 * overwrite either of them: this makes proc_dointvec_minmax
7213 		 * usable.
7214 		 */
7215 		if (!table[i].extra1 && !table[i].extra2) {
7216 			table[i].extra1 = idev; /* embedded; no ref */
7217 			table[i].extra2 = net;
7218 		}
7219 	}
7220 
7221 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
7222 
7223 	p->sysctl_header = register_net_sysctl_sz(net, path, table,
7224 						  table_size);
7225 	if (!p->sysctl_header)
7226 		goto free;
7227 
7228 	if (!strcmp(dev_name, "all"))
7229 		ifindex = NETCONFA_IFINDEX_ALL;
7230 	else if (!strcmp(dev_name, "default"))
7231 		ifindex = NETCONFA_IFINDEX_DEFAULT;
7232 	else
7233 		ifindex = idev->dev->ifindex;
7234 	inet6_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL,
7235 				     ifindex, p);
7236 	return 0;
7237 
7238 free:
7239 	kfree(table);
7240 out:
7241 	return -ENOBUFS;
7242 }
7243 
__addrconf_sysctl_unregister(struct net * net,struct ipv6_devconf * p,int ifindex)7244 static void __addrconf_sysctl_unregister(struct net *net,
7245 					 struct ipv6_devconf *p, int ifindex)
7246 {
7247 	const struct ctl_table *table;
7248 
7249 	if (!p->sysctl_header)
7250 		return;
7251 
7252 	table = p->sysctl_header->ctl_table_arg;
7253 	unregister_net_sysctl_table(p->sysctl_header);
7254 	p->sysctl_header = NULL;
7255 	kfree(table);
7256 
7257 	inet6_netconf_notify_devconf(net, RTM_DELNETCONF, 0, ifindex, NULL);
7258 }
7259 
addrconf_sysctl_register(struct inet6_dev * idev)7260 static int addrconf_sysctl_register(struct inet6_dev *idev)
7261 {
7262 	int err;
7263 
7264 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
7265 		return -EINVAL;
7266 
7267 	err = neigh_sysctl_register(idev->dev, idev->nd_parms,
7268 				    &ndisc_ifinfo_sysctl_change);
7269 	if (err)
7270 		return err;
7271 	err = __addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
7272 					 idev, &idev->cnf);
7273 	if (err)
7274 		neigh_sysctl_unregister(idev->nd_parms);
7275 
7276 	return err;
7277 }
7278 
addrconf_sysctl_unregister(struct inet6_dev * idev)7279 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
7280 {
7281 	__addrconf_sysctl_unregister(dev_net(idev->dev), &idev->cnf,
7282 				     idev->dev->ifindex);
7283 	neigh_sysctl_unregister(idev->nd_parms);
7284 }
7285 
7286 
7287 #endif
7288 
addrconf_init_net(struct net * net)7289 static int __net_init addrconf_init_net(struct net *net)
7290 {
7291 	int err = -ENOMEM;
7292 	struct ipv6_devconf *all, *dflt;
7293 
7294 	spin_lock_init(&net->ipv6.addrconf_hash_lock);
7295 	INIT_DEFERRABLE_WORK(&net->ipv6.addr_chk_work, addrconf_verify_work);
7296 	net->ipv6.inet6_addr_lst = kcalloc(IN6_ADDR_HSIZE,
7297 					   sizeof(struct hlist_head),
7298 					   GFP_KERNEL);
7299 	if (!net->ipv6.inet6_addr_lst)
7300 		goto err_alloc_addr;
7301 
7302 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
7303 	if (!all)
7304 		goto err_alloc_all;
7305 
7306 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
7307 	if (!dflt)
7308 		goto err_alloc_dflt;
7309 
7310 	if (!net_eq(net, &init_net)) {
7311 		switch (net_inherit_devconf()) {
7312 		case 1:  /* copy from init_net */
7313 			memcpy(all, init_net.ipv6.devconf_all,
7314 			       sizeof(ipv6_devconf));
7315 			memcpy(dflt, init_net.ipv6.devconf_dflt,
7316 			       sizeof(ipv6_devconf_dflt));
7317 			break;
7318 		case 3: /* copy from the current netns */
7319 			memcpy(all, current->nsproxy->net_ns->ipv6.devconf_all,
7320 			       sizeof(ipv6_devconf));
7321 			memcpy(dflt,
7322 			       current->nsproxy->net_ns->ipv6.devconf_dflt,
7323 			       sizeof(ipv6_devconf_dflt));
7324 			break;
7325 		case 0:
7326 		case 2:
7327 			/* use compiled values */
7328 			break;
7329 		}
7330 	}
7331 
7332 	/* these will be inherited by all namespaces */
7333 	dflt->autoconf = ipv6_defaults.autoconf;
7334 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
7335 
7336 	dflt->stable_secret.initialized = false;
7337 	all->stable_secret.initialized = false;
7338 
7339 	net->ipv6.devconf_all = all;
7340 	net->ipv6.devconf_dflt = dflt;
7341 
7342 #ifdef CONFIG_SYSCTL
7343 	err = __addrconf_sysctl_register(net, "all", NULL, all);
7344 	if (err < 0)
7345 		goto err_reg_all;
7346 
7347 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
7348 	if (err < 0)
7349 		goto err_reg_dflt;
7350 #endif
7351 	return 0;
7352 
7353 #ifdef CONFIG_SYSCTL
7354 err_reg_dflt:
7355 	__addrconf_sysctl_unregister(net, all, NETCONFA_IFINDEX_ALL);
7356 err_reg_all:
7357 	kfree(dflt);
7358 	net->ipv6.devconf_dflt = NULL;
7359 #endif
7360 err_alloc_dflt:
7361 	kfree(all);
7362 	net->ipv6.devconf_all = NULL;
7363 err_alloc_all:
7364 	kfree(net->ipv6.inet6_addr_lst);
7365 err_alloc_addr:
7366 	return err;
7367 }
7368 
addrconf_exit_net(struct net * net)7369 static void __net_exit addrconf_exit_net(struct net *net)
7370 {
7371 	int i;
7372 
7373 #ifdef CONFIG_SYSCTL
7374 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_dflt,
7375 				     NETCONFA_IFINDEX_DEFAULT);
7376 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_all,
7377 				     NETCONFA_IFINDEX_ALL);
7378 #endif
7379 	kfree(net->ipv6.devconf_dflt);
7380 	net->ipv6.devconf_dflt = NULL;
7381 	kfree(net->ipv6.devconf_all);
7382 	net->ipv6.devconf_all = NULL;
7383 
7384 	cancel_delayed_work_sync(&net->ipv6.addr_chk_work);
7385 	/*
7386 	 *	Check hash table, then free it.
7387 	 */
7388 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
7389 		WARN_ON_ONCE(!hlist_empty(&net->ipv6.inet6_addr_lst[i]));
7390 
7391 	kfree(net->ipv6.inet6_addr_lst);
7392 	net->ipv6.inet6_addr_lst = NULL;
7393 }
7394 
7395 static struct pernet_operations addrconf_ops = {
7396 	.init = addrconf_init_net,
7397 	.exit = addrconf_exit_net,
7398 };
7399 
7400 static struct rtnl_af_ops inet6_ops __read_mostly = {
7401 	.family		  = AF_INET6,
7402 	.fill_link_af	  = inet6_fill_link_af,
7403 	.get_link_af_size = inet6_get_link_af_size,
7404 	.validate_link_af = inet6_validate_link_af,
7405 	.set_link_af	  = inet6_set_link_af,
7406 };
7407 
7408 static const struct rtnl_msg_handler addrconf_rtnl_msg_handlers[] __initconst_or_module = {
7409 	{.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_GETLINK,
7410 	 .dumpit = inet6_dump_ifinfo, .flags = RTNL_FLAG_DUMP_UNLOCKED},
7411 	{.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_NEWADDR,
7412 	 .doit = inet6_rtm_newaddr, .flags = RTNL_FLAG_DOIT_PERNET},
7413 	{.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_DELADDR,
7414 	 .doit = inet6_rtm_deladdr, .flags = RTNL_FLAG_DOIT_PERNET},
7415 	{.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_GETADDR,
7416 	 .doit = inet6_rtm_getaddr, .dumpit = inet6_dump_ifaddr,
7417 	 .flags = RTNL_FLAG_DOIT_UNLOCKED | RTNL_FLAG_DUMP_UNLOCKED},
7418 	{.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_GETMULTICAST,
7419 	 .dumpit = inet6_dump_ifmcaddr,
7420 	 .flags = RTNL_FLAG_DUMP_UNLOCKED},
7421 	{.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_GETANYCAST,
7422 	 .dumpit = inet6_dump_ifacaddr,
7423 	 .flags = RTNL_FLAG_DUMP_UNLOCKED},
7424 	{.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_GETNETCONF,
7425 	 .doit = inet6_netconf_get_devconf, .dumpit = inet6_netconf_dump_devconf,
7426 	 .flags = RTNL_FLAG_DOIT_UNLOCKED | RTNL_FLAG_DUMP_UNLOCKED},
7427 };
7428 
7429 /*
7430  *	Init / cleanup code
7431  */
7432 
addrconf_init(void)7433 int __init addrconf_init(void)
7434 {
7435 	struct inet6_dev *idev;
7436 	int err;
7437 
7438 	err = ipv6_addr_label_init();
7439 	if (err < 0) {
7440 		pr_crit("%s: cannot initialize default policy table: %d\n",
7441 			__func__, err);
7442 		goto out;
7443 	}
7444 
7445 	err = register_pernet_subsys(&addrconf_ops);
7446 	if (err < 0)
7447 		goto out_addrlabel;
7448 
7449 	/* All works using addrconf_wq need to lock rtnl. */
7450 	addrconf_wq = create_singlethread_workqueue("ipv6_addrconf");
7451 	if (!addrconf_wq) {
7452 		err = -ENOMEM;
7453 		goto out_nowq;
7454 	}
7455 
7456 	rtnl_net_lock(&init_net);
7457 	idev = ipv6_add_dev(blackhole_netdev);
7458 	rtnl_net_unlock(&init_net);
7459 	if (IS_ERR(idev)) {
7460 		err = PTR_ERR(idev);
7461 		goto errlo;
7462 	}
7463 
7464 	ip6_route_init_special_entries();
7465 
7466 	register_netdevice_notifier(&ipv6_dev_notf);
7467 
7468 	addrconf_verify(&init_net);
7469 
7470 	err = rtnl_af_register(&inet6_ops);
7471 	if (err)
7472 		goto erraf;
7473 
7474 	err = rtnl_register_many(addrconf_rtnl_msg_handlers);
7475 	if (err)
7476 		goto errout;
7477 
7478 	err = ipv6_addr_label_rtnl_register();
7479 	if (err < 0)
7480 		goto errout;
7481 
7482 	return 0;
7483 errout:
7484 	rtnl_unregister_all(PF_INET6);
7485 	rtnl_af_unregister(&inet6_ops);
7486 erraf:
7487 	unregister_netdevice_notifier(&ipv6_dev_notf);
7488 errlo:
7489 	destroy_workqueue(addrconf_wq);
7490 out_nowq:
7491 	unregister_pernet_subsys(&addrconf_ops);
7492 out_addrlabel:
7493 	ipv6_addr_label_cleanup();
7494 out:
7495 	return err;
7496 }
7497 
addrconf_cleanup(void)7498 void addrconf_cleanup(void)
7499 {
7500 	struct net_device *dev;
7501 
7502 	unregister_netdevice_notifier(&ipv6_dev_notf);
7503 	unregister_pernet_subsys(&addrconf_ops);
7504 	ipv6_addr_label_cleanup();
7505 
7506 	rtnl_af_unregister(&inet6_ops);
7507 
7508 	rtnl_net_lock(&init_net);
7509 
7510 	/* clean dev list */
7511 	for_each_netdev(&init_net, dev) {
7512 		if (!__in6_dev_get_rtnl_net(dev))
7513 			continue;
7514 		addrconf_ifdown(dev, true);
7515 	}
7516 	addrconf_ifdown(init_net.loopback_dev, true);
7517 
7518 	rtnl_net_unlock(&init_net);
7519 
7520 	destroy_workqueue(addrconf_wq);
7521 }
7522