1 // SPDX-License-Identifier: GPL-2.0
3 * IPv6 Address Label subsystem
4 * for the IPv6 "Default" Source Address Selection
6 * Copyright (C)2007 USAGI/WIDE Project
10 * YOSHIFUJI Hideaki @ USAGI/WIDE Project <yoshfuji@linux-ipv6.org>
13 #include <linux/kernel.h>
14 #include <linux/list.h>
15 #include <linux/rcupdate.h>
16 #include <linux/in6.h>
17 #include <linux/slab.h>
18 #include <net/addrconf.h>
19 #include <linux/if_addrlabel.h>
20 #include <linux/netlink.h>
21 #include <linux/rtnetlink.h>
24 #define ADDRLABEL(x...) printk(x)
26 #define ADDRLABEL(x...) do { ; } while (0)
32 struct ip6addrlbl_entry {
33 struct in6_addr prefix;
38 struct hlist_node list;
43 * Default policy table (RFC6724 + extensions)
45 * prefix addr_type label
46 * -------------------------------------------------------------------------
51 * ::ffff:0:0/96 V4MAPPED 4
52 * fc00::/7 N/A 5 ULA (RFC 4193)
53 * 2001::/32 N/A 6 Teredo (RFC 4380)
54 * 2001:10::/28 N/A 7 ORCHID (RFC 4843)
55 * fec0::/10 N/A 11 Site-local
56 * (deprecated by RFC3879)
57 * 3ffe::/16 N/A 12 6bone
59 * Note: 0xffffffff is used if we do not have any policies.
60 * Note: Labels for ULA and 6to4 are different from labels listed in RFC6724.
63 #define IPV6_ADDR_LABEL_DEFAULT 0xffffffffUL
65 static const __net_initconst struct ip6addrlbl_init_table
67 const struct in6_addr *prefix;
70 } ip6addrlbl_init_table[] = {
72 .prefix = &in6addr_any,
75 .prefix = &(struct in6_addr){ { { 0xfc } } } ,
79 .prefix = &(struct in6_addr){ { { 0xfe, 0xc0 } } },
83 .prefix = &(struct in6_addr){ { { 0x20, 0x02 } } },
87 .prefix = &(struct in6_addr){ { { 0x3f, 0xfe } } },
91 .prefix = &(struct in6_addr){ { { 0x20, 0x01 } } },
94 }, { /* 2001:10::/28 */
95 .prefix = &(struct in6_addr){ { { 0x20, 0x01, 0x00, 0x10 } } },
99 .prefix = &(struct in6_addr){ { { [10] = 0xff, [11] = 0xff } } },
103 .prefix = &in6addr_any,
107 .prefix = &in6addr_loopback,
114 static bool __ip6addrlbl_match(const struct ip6addrlbl_entry *p,
115 const struct in6_addr *addr,
116 int addrtype, int ifindex)
118 if (p->ifindex && p->ifindex != ifindex)
120 if (p->addrtype && p->addrtype != addrtype)
122 if (!ipv6_prefix_equal(addr, &p->prefix, p->prefixlen))
127 static struct ip6addrlbl_entry *__ipv6_addr_label(struct net *net,
128 const struct in6_addr *addr,
129 int type, int ifindex)
131 struct ip6addrlbl_entry *p;
133 hlist_for_each_entry_rcu(p, &net->ipv6.ip6addrlbl_table.head, list) {
134 if (__ip6addrlbl_match(p, addr, type, ifindex))
140 u32 ipv6_addr_label(struct net *net,
141 const struct in6_addr *addr, int type, int ifindex)
144 struct ip6addrlbl_entry *p;
146 type &= IPV6_ADDR_MAPPED | IPV6_ADDR_COMPATv4 | IPV6_ADDR_LOOPBACK;
149 p = __ipv6_addr_label(net, addr, type, ifindex);
150 label = p ? p->label : IPV6_ADDR_LABEL_DEFAULT;
153 ADDRLABEL(KERN_DEBUG "%s(addr=%pI6, type=%d, ifindex=%d) => %08x\n",
154 __func__, addr, type, ifindex, label);
159 /* allocate one entry */
160 static struct ip6addrlbl_entry *ip6addrlbl_alloc(const struct in6_addr *prefix,
161 int prefixlen, int ifindex,
164 struct ip6addrlbl_entry *newp;
167 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d, label=%u)\n",
168 __func__, prefix, prefixlen, ifindex, (unsigned int)label);
170 addrtype = ipv6_addr_type(prefix) & (IPV6_ADDR_MAPPED | IPV6_ADDR_COMPATv4 | IPV6_ADDR_LOOPBACK);
173 case IPV6_ADDR_MAPPED:
175 return ERR_PTR(-EINVAL);
179 case IPV6_ADDR_COMPATv4:
183 case IPV6_ADDR_LOOPBACK:
184 if (prefixlen != 128)
189 newp = kmalloc(sizeof(*newp), GFP_KERNEL);
191 return ERR_PTR(-ENOMEM);
193 ipv6_addr_prefix(&newp->prefix, prefix, prefixlen);
194 newp->prefixlen = prefixlen;
195 newp->ifindex = ifindex;
196 newp->addrtype = addrtype;
198 INIT_HLIST_NODE(&newp->list);
203 static int __ip6addrlbl_add(struct net *net, struct ip6addrlbl_entry *newp,
206 struct ip6addrlbl_entry *last = NULL, *p = NULL;
207 struct hlist_node *n;
210 ADDRLABEL(KERN_DEBUG "%s(newp=%p, replace=%d)\n", __func__, newp,
213 hlist_for_each_entry_safe(p, n, &net->ipv6.ip6addrlbl_table.head, list) {
214 if (p->prefixlen == newp->prefixlen &&
215 p->ifindex == newp->ifindex &&
216 ipv6_addr_equal(&p->prefix, &newp->prefix)) {
221 hlist_replace_rcu(&p->list, &newp->list);
224 } else if ((p->prefixlen == newp->prefixlen && !p->ifindex) ||
225 (p->prefixlen < newp->prefixlen)) {
226 hlist_add_before_rcu(&newp->list, &p->list);
232 hlist_add_behind_rcu(&newp->list, &last->list);
234 hlist_add_head_rcu(&newp->list, &net->ipv6.ip6addrlbl_table.head);
237 net->ipv6.ip6addrlbl_table.seq++;
242 static int ip6addrlbl_add(struct net *net,
243 const struct in6_addr *prefix, int prefixlen,
244 int ifindex, u32 label, int replace)
246 struct ip6addrlbl_entry *newp;
249 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d, label=%u, replace=%d)\n",
250 __func__, prefix, prefixlen, ifindex, (unsigned int)label,
253 newp = ip6addrlbl_alloc(prefix, prefixlen, ifindex, label);
255 return PTR_ERR(newp);
256 spin_lock(&net->ipv6.ip6addrlbl_table.lock);
257 ret = __ip6addrlbl_add(net, newp, replace);
258 spin_unlock(&net->ipv6.ip6addrlbl_table.lock);
265 static int __ip6addrlbl_del(struct net *net,
266 const struct in6_addr *prefix, int prefixlen,
269 struct ip6addrlbl_entry *p = NULL;
270 struct hlist_node *n;
273 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d)\n",
274 __func__, prefix, prefixlen, ifindex);
276 hlist_for_each_entry_safe(p, n, &net->ipv6.ip6addrlbl_table.head, list) {
277 if (p->prefixlen == prefixlen &&
278 p->ifindex == ifindex &&
279 ipv6_addr_equal(&p->prefix, prefix)) {
280 hlist_del_rcu(&p->list);
289 static int ip6addrlbl_del(struct net *net,
290 const struct in6_addr *prefix, int prefixlen,
293 struct in6_addr prefix_buf;
296 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d)\n",
297 __func__, prefix, prefixlen, ifindex);
299 ipv6_addr_prefix(&prefix_buf, prefix, prefixlen);
300 spin_lock(&net->ipv6.ip6addrlbl_table.lock);
301 ret = __ip6addrlbl_del(net, &prefix_buf, prefixlen, ifindex);
302 spin_unlock(&net->ipv6.ip6addrlbl_table.lock);
306 /* add default label */
307 static int __net_init ip6addrlbl_net_init(struct net *net)
309 struct ip6addrlbl_entry *p = NULL;
310 struct hlist_node *n;
314 ADDRLABEL(KERN_DEBUG "%s\n", __func__);
316 spin_lock_init(&net->ipv6.ip6addrlbl_table.lock);
317 INIT_HLIST_HEAD(&net->ipv6.ip6addrlbl_table.head);
319 for (i = 0; i < ARRAY_SIZE(ip6addrlbl_init_table); i++) {
320 err = ip6addrlbl_add(net,
321 ip6addrlbl_init_table[i].prefix,
322 ip6addrlbl_init_table[i].prefixlen,
324 ip6addrlbl_init_table[i].label, 0);
326 goto err_ip6addrlbl_add;
331 hlist_for_each_entry_safe(p, n, &net->ipv6.ip6addrlbl_table.head, list) {
332 hlist_del_rcu(&p->list);
338 static void __net_exit ip6addrlbl_net_exit(struct net *net)
340 struct ip6addrlbl_entry *p = NULL;
341 struct hlist_node *n;
343 /* Remove all labels belonging to the exiting net */
344 spin_lock(&net->ipv6.ip6addrlbl_table.lock);
345 hlist_for_each_entry_safe(p, n, &net->ipv6.ip6addrlbl_table.head, list) {
346 hlist_del_rcu(&p->list);
349 spin_unlock(&net->ipv6.ip6addrlbl_table.lock);
352 static struct pernet_operations ipv6_addr_label_ops = {
353 .init = ip6addrlbl_net_init,
354 .exit = ip6addrlbl_net_exit,
357 int __init ipv6_addr_label_init(void)
359 return register_pernet_subsys(&ipv6_addr_label_ops);
362 void ipv6_addr_label_cleanup(void)
364 unregister_pernet_subsys(&ipv6_addr_label_ops);
367 static const struct nla_policy ifal_policy[IFAL_MAX+1] = {
368 [IFAL_ADDRESS] = { .len = sizeof(struct in6_addr), },
369 [IFAL_LABEL] = { .len = sizeof(u32), },
372 static bool addrlbl_ifindex_exists(struct net *net, int ifindex)
375 struct net_device *dev;
378 dev = dev_get_by_index_rcu(net, ifindex);
384 static int ip6addrlbl_newdel(struct sk_buff *skb, struct nlmsghdr *nlh,
385 struct netlink_ext_ack *extack)
387 struct net *net = sock_net(skb->sk);
388 struct ifaddrlblmsg *ifal;
389 struct nlattr *tb[IFAL_MAX+1];
390 struct in6_addr *pfx;
394 err = nlmsg_parse_deprecated(nlh, sizeof(*ifal), tb, IFAL_MAX,
395 ifal_policy, extack);
399 ifal = nlmsg_data(nlh);
401 if (ifal->ifal_family != AF_INET6 ||
402 ifal->ifal_prefixlen > 128)
405 if (!tb[IFAL_ADDRESS])
407 pfx = nla_data(tb[IFAL_ADDRESS]);
411 label = nla_get_u32(tb[IFAL_LABEL]);
412 if (label == IPV6_ADDR_LABEL_DEFAULT)
415 switch (nlh->nlmsg_type) {
416 case RTM_NEWADDRLABEL:
417 if (ifal->ifal_index &&
418 !addrlbl_ifindex_exists(net, ifal->ifal_index))
421 err = ip6addrlbl_add(net, pfx, ifal->ifal_prefixlen,
422 ifal->ifal_index, label,
423 nlh->nlmsg_flags & NLM_F_REPLACE);
425 case RTM_DELADDRLABEL:
426 err = ip6addrlbl_del(net, pfx, ifal->ifal_prefixlen,
435 static void ip6addrlbl_putmsg(struct nlmsghdr *nlh,
436 int prefixlen, int ifindex, u32 lseq)
438 struct ifaddrlblmsg *ifal = nlmsg_data(nlh);
439 ifal->ifal_family = AF_INET6;
440 ifal->ifal_prefixlen = prefixlen;
441 ifal->ifal_flags = 0;
442 ifal->ifal_index = ifindex;
443 ifal->ifal_seq = lseq;
446 static int ip6addrlbl_fill(struct sk_buff *skb,
447 struct ip6addrlbl_entry *p,
449 u32 portid, u32 seq, int event,
452 struct nlmsghdr *nlh = nlmsg_put(skb, portid, seq, event,
453 sizeof(struct ifaddrlblmsg), flags);
457 ip6addrlbl_putmsg(nlh, p->prefixlen, p->ifindex, lseq);
459 if (nla_put_in6_addr(skb, IFAL_ADDRESS, &p->prefix) < 0 ||
460 nla_put_u32(skb, IFAL_LABEL, p->label) < 0) {
461 nlmsg_cancel(skb, nlh);
469 static int ip6addrlbl_valid_dump_req(const struct nlmsghdr *nlh,
470 struct netlink_ext_ack *extack)
472 struct ifaddrlblmsg *ifal;
474 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifal))) {
475 NL_SET_ERR_MSG_MOD(extack, "Invalid header for address label dump request");
479 ifal = nlmsg_data(nlh);
480 if (ifal->__ifal_reserved || ifal->ifal_prefixlen ||
481 ifal->ifal_flags || ifal->ifal_index || ifal->ifal_seq) {
482 NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for address label dump request");
486 if (nlmsg_attrlen(nlh, sizeof(*ifal))) {
487 NL_SET_ERR_MSG_MOD(extack, "Invalid data after header for address label dump request");
494 static int ip6addrlbl_dump(struct sk_buff *skb, struct netlink_callback *cb)
496 const struct nlmsghdr *nlh = cb->nlh;
497 struct net *net = sock_net(skb->sk);
498 struct ip6addrlbl_entry *p;
499 int idx = 0, s_idx = cb->args[0];
502 if (cb->strict_check) {
503 err = ip6addrlbl_valid_dump_req(nlh, cb->extack);
509 hlist_for_each_entry_rcu(p, &net->ipv6.ip6addrlbl_table.head, list) {
511 err = ip6addrlbl_fill(skb, p,
512 net->ipv6.ip6addrlbl_table.seq,
513 NETLINK_CB(cb->skb).portid,
527 static inline int ip6addrlbl_msgsize(void)
529 return NLMSG_ALIGN(sizeof(struct ifaddrlblmsg))
530 + nla_total_size(16) /* IFAL_ADDRESS */
531 + nla_total_size(4); /* IFAL_LABEL */
534 static int ip6addrlbl_valid_get_req(struct sk_buff *skb,
535 const struct nlmsghdr *nlh,
537 struct netlink_ext_ack *extack)
539 struct ifaddrlblmsg *ifal;
542 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifal))) {
543 NL_SET_ERR_MSG_MOD(extack, "Invalid header for addrlabel get request");
547 if (!netlink_strict_get_check(skb))
548 return nlmsg_parse_deprecated(nlh, sizeof(*ifal), tb,
549 IFAL_MAX, ifal_policy, extack);
551 ifal = nlmsg_data(nlh);
552 if (ifal->__ifal_reserved || ifal->ifal_flags || ifal->ifal_seq) {
553 NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for addrlabel get request");
557 err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifal), tb, IFAL_MAX,
558 ifal_policy, extack);
562 for (i = 0; i <= IFAL_MAX; i++) {
570 NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in addrlabel get request");
578 static int ip6addrlbl_get(struct sk_buff *in_skb, struct nlmsghdr *nlh,
579 struct netlink_ext_ack *extack)
581 struct net *net = sock_net(in_skb->sk);
582 struct ifaddrlblmsg *ifal;
583 struct nlattr *tb[IFAL_MAX+1];
584 struct in6_addr *addr;
587 struct ip6addrlbl_entry *p;
590 err = ip6addrlbl_valid_get_req(in_skb, nlh, tb, extack);
594 ifal = nlmsg_data(nlh);
596 if (ifal->ifal_family != AF_INET6 ||
597 ifal->ifal_prefixlen != 128)
600 if (ifal->ifal_index &&
601 !addrlbl_ifindex_exists(net, ifal->ifal_index))
604 if (!tb[IFAL_ADDRESS])
606 addr = nla_data(tb[IFAL_ADDRESS]);
608 skb = nlmsg_new(ip6addrlbl_msgsize(), GFP_KERNEL);
615 p = __ipv6_addr_label(net, addr, ipv6_addr_type(addr), ifal->ifal_index);
616 lseq = net->ipv6.ip6addrlbl_table.seq;
618 err = ip6addrlbl_fill(skb, p, lseq,
619 NETLINK_CB(in_skb).portid,
621 RTM_NEWADDRLABEL, 0);
625 WARN_ON(err == -EMSGSIZE);
628 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
633 int __init ipv6_addr_label_rtnl_register(void)
637 ret = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_NEWADDRLABEL,
639 NULL, RTNL_FLAG_DOIT_UNLOCKED);
642 ret = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_DELADDRLABEL,
644 NULL, RTNL_FLAG_DOIT_UNLOCKED);
647 ret = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETADDRLABEL,
649 ip6addrlbl_dump, RTNL_FLAG_DOIT_UNLOCKED);