Merge tag 'iio-for-5.5c' of https://git.kernel.org/pub/scm/linux/kernel/git/jic23...
[linux/fpc-iii.git] / net / mpls / af_mpls.c
blobc312741df2ce9edb84ab5e60697d98bf0286d500
1 // SPDX-License-Identifier: GPL-2.0-only
2 #include <linux/types.h>
3 #include <linux/skbuff.h>
4 #include <linux/socket.h>
5 #include <linux/sysctl.h>
6 #include <linux/net.h>
7 #include <linux/module.h>
8 #include <linux/if_arp.h>
9 #include <linux/ipv6.h>
10 #include <linux/mpls.h>
11 #include <linux/netconf.h>
12 #include <linux/nospec.h>
13 #include <linux/vmalloc.h>
14 #include <linux/percpu.h>
15 #include <net/ip.h>
16 #include <net/dst.h>
17 #include <net/sock.h>
18 #include <net/arp.h>
19 #include <net/ip_fib.h>
20 #include <net/netevent.h>
21 #include <net/ip_tunnels.h>
22 #include <net/netns/generic.h>
23 #if IS_ENABLED(CONFIG_IPV6)
24 #include <net/ipv6.h>
25 #endif
26 #include <net/ipv6_stubs.h>
27 #include <net/rtnh.h>
28 #include "internal.h"
30 /* max memory we will use for mpls_route */
31 #define MAX_MPLS_ROUTE_MEM 4096
33 /* Maximum number of labels to look ahead at when selecting a path of
34 * a multipath route
36 #define MAX_MP_SELECT_LABELS 4
38 #define MPLS_NEIGH_TABLE_UNSPEC (NEIGH_LINK_TABLE + 1)
40 static int label_limit = (1 << 20) - 1;
41 static int ttl_max = 255;
43 #if IS_ENABLED(CONFIG_NET_IP_TUNNEL)
44 static size_t ipgre_mpls_encap_hlen(struct ip_tunnel_encap *e)
46 return sizeof(struct mpls_shim_hdr);
49 static const struct ip_tunnel_encap_ops mpls_iptun_ops = {
50 .encap_hlen = ipgre_mpls_encap_hlen,
53 static int ipgre_tunnel_encap_add_mpls_ops(void)
55 return ip_tunnel_encap_add_ops(&mpls_iptun_ops, TUNNEL_ENCAP_MPLS);
58 static void ipgre_tunnel_encap_del_mpls_ops(void)
60 ip_tunnel_encap_del_ops(&mpls_iptun_ops, TUNNEL_ENCAP_MPLS);
62 #else
63 static int ipgre_tunnel_encap_add_mpls_ops(void)
65 return 0;
68 static void ipgre_tunnel_encap_del_mpls_ops(void)
71 #endif
73 static void rtmsg_lfib(int event, u32 label, struct mpls_route *rt,
74 struct nlmsghdr *nlh, struct net *net, u32 portid,
75 unsigned int nlm_flags);
77 static struct mpls_route *mpls_route_input_rcu(struct net *net, unsigned index)
79 struct mpls_route *rt = NULL;
81 if (index < net->mpls.platform_labels) {
82 struct mpls_route __rcu **platform_label =
83 rcu_dereference(net->mpls.platform_label);
84 rt = rcu_dereference(platform_label[index]);
86 return rt;
89 bool mpls_output_possible(const struct net_device *dev)
91 return dev && (dev->flags & IFF_UP) && netif_carrier_ok(dev);
93 EXPORT_SYMBOL_GPL(mpls_output_possible);
95 static u8 *__mpls_nh_via(struct mpls_route *rt, struct mpls_nh *nh)
97 return (u8 *)nh + rt->rt_via_offset;
100 static const u8 *mpls_nh_via(const struct mpls_route *rt,
101 const struct mpls_nh *nh)
103 return __mpls_nh_via((struct mpls_route *)rt, (struct mpls_nh *)nh);
106 static unsigned int mpls_nh_header_size(const struct mpls_nh *nh)
108 /* The size of the layer 2.5 labels to be added for this route */
109 return nh->nh_labels * sizeof(struct mpls_shim_hdr);
112 unsigned int mpls_dev_mtu(const struct net_device *dev)
114 /* The amount of data the layer 2 frame can hold */
115 return dev->mtu;
117 EXPORT_SYMBOL_GPL(mpls_dev_mtu);
119 bool mpls_pkt_too_big(const struct sk_buff *skb, unsigned int mtu)
121 if (skb->len <= mtu)
122 return false;
124 if (skb_is_gso(skb) && skb_gso_validate_network_len(skb, mtu))
125 return false;
127 return true;
129 EXPORT_SYMBOL_GPL(mpls_pkt_too_big);
131 void mpls_stats_inc_outucastpkts(struct net_device *dev,
132 const struct sk_buff *skb)
134 struct mpls_dev *mdev;
136 if (skb->protocol == htons(ETH_P_MPLS_UC)) {
137 mdev = mpls_dev_get(dev);
138 if (mdev)
139 MPLS_INC_STATS_LEN(mdev, skb->len,
140 tx_packets,
141 tx_bytes);
142 } else if (skb->protocol == htons(ETH_P_IP)) {
143 IP_UPD_PO_STATS(dev_net(dev), IPSTATS_MIB_OUT, skb->len);
144 #if IS_ENABLED(CONFIG_IPV6)
145 } else if (skb->protocol == htons(ETH_P_IPV6)) {
146 struct inet6_dev *in6dev = __in6_dev_get(dev);
148 if (in6dev)
149 IP6_UPD_PO_STATS(dev_net(dev), in6dev,
150 IPSTATS_MIB_OUT, skb->len);
151 #endif
154 EXPORT_SYMBOL_GPL(mpls_stats_inc_outucastpkts);
156 static u32 mpls_multipath_hash(struct mpls_route *rt, struct sk_buff *skb)
158 struct mpls_entry_decoded dec;
159 unsigned int mpls_hdr_len = 0;
160 struct mpls_shim_hdr *hdr;
161 bool eli_seen = false;
162 int label_index;
163 u32 hash = 0;
165 for (label_index = 0; label_index < MAX_MP_SELECT_LABELS;
166 label_index++) {
167 mpls_hdr_len += sizeof(*hdr);
168 if (!pskb_may_pull(skb, mpls_hdr_len))
169 break;
171 /* Read and decode the current label */
172 hdr = mpls_hdr(skb) + label_index;
173 dec = mpls_entry_decode(hdr);
175 /* RFC6790 - reserved labels MUST NOT be used as keys
176 * for the load-balancing function
178 if (likely(dec.label >= MPLS_LABEL_FIRST_UNRESERVED)) {
179 hash = jhash_1word(dec.label, hash);
181 /* The entropy label follows the entropy label
182 * indicator, so this means that the entropy
183 * label was just added to the hash - no need to
184 * go any deeper either in the label stack or in the
185 * payload
187 if (eli_seen)
188 break;
189 } else if (dec.label == MPLS_LABEL_ENTROPY) {
190 eli_seen = true;
193 if (!dec.bos)
194 continue;
196 /* found bottom label; does skb have room for a header? */
197 if (pskb_may_pull(skb, mpls_hdr_len + sizeof(struct iphdr))) {
198 const struct iphdr *v4hdr;
200 v4hdr = (const struct iphdr *)(hdr + 1);
201 if (v4hdr->version == 4) {
202 hash = jhash_3words(ntohl(v4hdr->saddr),
203 ntohl(v4hdr->daddr),
204 v4hdr->protocol, hash);
205 } else if (v4hdr->version == 6 &&
206 pskb_may_pull(skb, mpls_hdr_len +
207 sizeof(struct ipv6hdr))) {
208 const struct ipv6hdr *v6hdr;
210 v6hdr = (const struct ipv6hdr *)(hdr + 1);
211 hash = __ipv6_addr_jhash(&v6hdr->saddr, hash);
212 hash = __ipv6_addr_jhash(&v6hdr->daddr, hash);
213 hash = jhash_1word(v6hdr->nexthdr, hash);
217 break;
220 return hash;
223 static struct mpls_nh *mpls_get_nexthop(struct mpls_route *rt, u8 index)
225 return (struct mpls_nh *)((u8 *)rt->rt_nh + index * rt->rt_nh_size);
228 /* number of alive nexthops (rt->rt_nhn_alive) and the flags for
229 * a next hop (nh->nh_flags) are modified by netdev event handlers.
230 * Since those fields can change at any moment, use READ_ONCE to
231 * access both.
233 static struct mpls_nh *mpls_select_multipath(struct mpls_route *rt,
234 struct sk_buff *skb)
236 u32 hash = 0;
237 int nh_index = 0;
238 int n = 0;
239 u8 alive;
241 /* No need to look further into packet if there's only
242 * one path
244 if (rt->rt_nhn == 1)
245 return rt->rt_nh;
247 alive = READ_ONCE(rt->rt_nhn_alive);
248 if (alive == 0)
249 return NULL;
251 hash = mpls_multipath_hash(rt, skb);
252 nh_index = hash % alive;
253 if (alive == rt->rt_nhn)
254 goto out;
255 for_nexthops(rt) {
256 unsigned int nh_flags = READ_ONCE(nh->nh_flags);
258 if (nh_flags & (RTNH_F_DEAD | RTNH_F_LINKDOWN))
259 continue;
260 if (n == nh_index)
261 return nh;
262 n++;
263 } endfor_nexthops(rt);
265 out:
266 return mpls_get_nexthop(rt, nh_index);
269 static bool mpls_egress(struct net *net, struct mpls_route *rt,
270 struct sk_buff *skb, struct mpls_entry_decoded dec)
272 enum mpls_payload_type payload_type;
273 bool success = false;
275 /* The IPv4 code below accesses through the IPv4 header
276 * checksum, which is 12 bytes into the packet.
277 * The IPv6 code below accesses through the IPv6 hop limit
278 * which is 8 bytes into the packet.
280 * For all supported cases there should always be at least 12
281 * bytes of packet data present. The IPv4 header is 20 bytes
282 * without options and the IPv6 header is always 40 bytes
283 * long.
285 if (!pskb_may_pull(skb, 12))
286 return false;
288 payload_type = rt->rt_payload_type;
289 if (payload_type == MPT_UNSPEC)
290 payload_type = ip_hdr(skb)->version;
292 switch (payload_type) {
293 case MPT_IPV4: {
294 struct iphdr *hdr4 = ip_hdr(skb);
295 u8 new_ttl;
296 skb->protocol = htons(ETH_P_IP);
298 /* If propagating TTL, take the decremented TTL from
299 * the incoming MPLS header, otherwise decrement the
300 * TTL, but only if not 0 to avoid underflow.
302 if (rt->rt_ttl_propagate == MPLS_TTL_PROP_ENABLED ||
303 (rt->rt_ttl_propagate == MPLS_TTL_PROP_DEFAULT &&
304 net->mpls.ip_ttl_propagate))
305 new_ttl = dec.ttl;
306 else
307 new_ttl = hdr4->ttl ? hdr4->ttl - 1 : 0;
309 csum_replace2(&hdr4->check,
310 htons(hdr4->ttl << 8),
311 htons(new_ttl << 8));
312 hdr4->ttl = new_ttl;
313 success = true;
314 break;
316 case MPT_IPV6: {
317 struct ipv6hdr *hdr6 = ipv6_hdr(skb);
318 skb->protocol = htons(ETH_P_IPV6);
320 /* If propagating TTL, take the decremented TTL from
321 * the incoming MPLS header, otherwise decrement the
322 * hop limit, but only if not 0 to avoid underflow.
324 if (rt->rt_ttl_propagate == MPLS_TTL_PROP_ENABLED ||
325 (rt->rt_ttl_propagate == MPLS_TTL_PROP_DEFAULT &&
326 net->mpls.ip_ttl_propagate))
327 hdr6->hop_limit = dec.ttl;
328 else if (hdr6->hop_limit)
329 hdr6->hop_limit = hdr6->hop_limit - 1;
330 success = true;
331 break;
333 case MPT_UNSPEC:
334 /* Should have decided which protocol it is by now */
335 break;
338 return success;
341 static int mpls_forward(struct sk_buff *skb, struct net_device *dev,
342 struct packet_type *pt, struct net_device *orig_dev)
344 struct net *net = dev_net(dev);
345 struct mpls_shim_hdr *hdr;
346 struct mpls_route *rt;
347 struct mpls_nh *nh;
348 struct mpls_entry_decoded dec;
349 struct net_device *out_dev;
350 struct mpls_dev *out_mdev;
351 struct mpls_dev *mdev;
352 unsigned int hh_len;
353 unsigned int new_header_size;
354 unsigned int mtu;
355 int err;
357 /* Careful this entire function runs inside of an rcu critical section */
359 mdev = mpls_dev_get(dev);
360 if (!mdev)
361 goto drop;
363 MPLS_INC_STATS_LEN(mdev, skb->len, rx_packets,
364 rx_bytes);
366 if (!mdev->input_enabled) {
367 MPLS_INC_STATS(mdev, rx_dropped);
368 goto drop;
371 if (skb->pkt_type != PACKET_HOST)
372 goto err;
374 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
375 goto err;
377 if (!pskb_may_pull(skb, sizeof(*hdr)))
378 goto err;
380 /* Read and decode the label */
381 hdr = mpls_hdr(skb);
382 dec = mpls_entry_decode(hdr);
384 rt = mpls_route_input_rcu(net, dec.label);
385 if (!rt) {
386 MPLS_INC_STATS(mdev, rx_noroute);
387 goto drop;
390 nh = mpls_select_multipath(rt, skb);
391 if (!nh)
392 goto err;
394 /* Pop the label */
395 skb_pull(skb, sizeof(*hdr));
396 skb_reset_network_header(skb);
398 skb_orphan(skb);
400 if (skb_warn_if_lro(skb))
401 goto err;
403 skb_forward_csum(skb);
405 /* Verify ttl is valid */
406 if (dec.ttl <= 1)
407 goto err;
408 dec.ttl -= 1;
410 /* Find the output device */
411 out_dev = rcu_dereference(nh->nh_dev);
412 if (!mpls_output_possible(out_dev))
413 goto tx_err;
415 /* Verify the destination can hold the packet */
416 new_header_size = mpls_nh_header_size(nh);
417 mtu = mpls_dev_mtu(out_dev);
418 if (mpls_pkt_too_big(skb, mtu - new_header_size))
419 goto tx_err;
421 hh_len = LL_RESERVED_SPACE(out_dev);
422 if (!out_dev->header_ops)
423 hh_len = 0;
425 /* Ensure there is enough space for the headers in the skb */
426 if (skb_cow(skb, hh_len + new_header_size))
427 goto tx_err;
429 skb->dev = out_dev;
430 skb->protocol = htons(ETH_P_MPLS_UC);
432 if (unlikely(!new_header_size && dec.bos)) {
433 /* Penultimate hop popping */
434 if (!mpls_egress(dev_net(out_dev), rt, skb, dec))
435 goto err;
436 } else {
437 bool bos;
438 int i;
439 skb_push(skb, new_header_size);
440 skb_reset_network_header(skb);
441 /* Push the new labels */
442 hdr = mpls_hdr(skb);
443 bos = dec.bos;
444 for (i = nh->nh_labels - 1; i >= 0; i--) {
445 hdr[i] = mpls_entry_encode(nh->nh_label[i],
446 dec.ttl, 0, bos);
447 bos = false;
451 mpls_stats_inc_outucastpkts(out_dev, skb);
453 /* If via wasn't specified then send out using device address */
454 if (nh->nh_via_table == MPLS_NEIGH_TABLE_UNSPEC)
455 err = neigh_xmit(NEIGH_LINK_TABLE, out_dev,
456 out_dev->dev_addr, skb);
457 else
458 err = neigh_xmit(nh->nh_via_table, out_dev,
459 mpls_nh_via(rt, nh), skb);
460 if (err)
461 net_dbg_ratelimited("%s: packet transmission failed: %d\n",
462 __func__, err);
463 return 0;
465 tx_err:
466 out_mdev = out_dev ? mpls_dev_get(out_dev) : NULL;
467 if (out_mdev)
468 MPLS_INC_STATS(out_mdev, tx_errors);
469 goto drop;
470 err:
471 MPLS_INC_STATS(mdev, rx_errors);
472 drop:
473 kfree_skb(skb);
474 return NET_RX_DROP;
477 static struct packet_type mpls_packet_type __read_mostly = {
478 .type = cpu_to_be16(ETH_P_MPLS_UC),
479 .func = mpls_forward,
482 static const struct nla_policy rtm_mpls_policy[RTA_MAX+1] = {
483 [RTA_DST] = { .type = NLA_U32 },
484 [RTA_OIF] = { .type = NLA_U32 },
485 [RTA_TTL_PROPAGATE] = { .type = NLA_U8 },
488 struct mpls_route_config {
489 u32 rc_protocol;
490 u32 rc_ifindex;
491 u8 rc_via_table;
492 u8 rc_via_alen;
493 u8 rc_via[MAX_VIA_ALEN];
494 u32 rc_label;
495 u8 rc_ttl_propagate;
496 u8 rc_output_labels;
497 u32 rc_output_label[MAX_NEW_LABELS];
498 u32 rc_nlflags;
499 enum mpls_payload_type rc_payload_type;
500 struct nl_info rc_nlinfo;
501 struct rtnexthop *rc_mp;
502 int rc_mp_len;
505 /* all nexthops within a route have the same size based on max
506 * number of labels and max via length for a hop
508 static struct mpls_route *mpls_rt_alloc(u8 num_nh, u8 max_alen, u8 max_labels)
510 u8 nh_size = MPLS_NH_SIZE(max_labels, max_alen);
511 struct mpls_route *rt;
512 size_t size;
514 size = sizeof(*rt) + num_nh * nh_size;
515 if (size > MAX_MPLS_ROUTE_MEM)
516 return ERR_PTR(-EINVAL);
518 rt = kzalloc(size, GFP_KERNEL);
519 if (!rt)
520 return ERR_PTR(-ENOMEM);
522 rt->rt_nhn = num_nh;
523 rt->rt_nhn_alive = num_nh;
524 rt->rt_nh_size = nh_size;
525 rt->rt_via_offset = MPLS_NH_VIA_OFF(max_labels);
527 return rt;
530 static void mpls_rt_free(struct mpls_route *rt)
532 if (rt)
533 kfree_rcu(rt, rt_rcu);
536 static void mpls_notify_route(struct net *net, unsigned index,
537 struct mpls_route *old, struct mpls_route *new,
538 const struct nl_info *info)
540 struct nlmsghdr *nlh = info ? info->nlh : NULL;
541 unsigned portid = info ? info->portid : 0;
542 int event = new ? RTM_NEWROUTE : RTM_DELROUTE;
543 struct mpls_route *rt = new ? new : old;
544 unsigned nlm_flags = (old && new) ? NLM_F_REPLACE : 0;
545 /* Ignore reserved labels for now */
546 if (rt && (index >= MPLS_LABEL_FIRST_UNRESERVED))
547 rtmsg_lfib(event, index, rt, nlh, net, portid, nlm_flags);
550 static void mpls_route_update(struct net *net, unsigned index,
551 struct mpls_route *new,
552 const struct nl_info *info)
554 struct mpls_route __rcu **platform_label;
555 struct mpls_route *rt;
557 ASSERT_RTNL();
559 platform_label = rtnl_dereference(net->mpls.platform_label);
560 rt = rtnl_dereference(platform_label[index]);
561 rcu_assign_pointer(platform_label[index], new);
563 mpls_notify_route(net, index, rt, new, info);
565 /* If we removed a route free it now */
566 mpls_rt_free(rt);
569 static unsigned find_free_label(struct net *net)
571 struct mpls_route __rcu **platform_label;
572 size_t platform_labels;
573 unsigned index;
575 platform_label = rtnl_dereference(net->mpls.platform_label);
576 platform_labels = net->mpls.platform_labels;
577 for (index = MPLS_LABEL_FIRST_UNRESERVED; index < platform_labels;
578 index++) {
579 if (!rtnl_dereference(platform_label[index]))
580 return index;
582 return LABEL_NOT_SPECIFIED;
585 #if IS_ENABLED(CONFIG_INET)
586 static struct net_device *inet_fib_lookup_dev(struct net *net,
587 const void *addr)
589 struct net_device *dev;
590 struct rtable *rt;
591 struct in_addr daddr;
593 memcpy(&daddr, addr, sizeof(struct in_addr));
594 rt = ip_route_output(net, daddr.s_addr, 0, 0, 0);
595 if (IS_ERR(rt))
596 return ERR_CAST(rt);
598 dev = rt->dst.dev;
599 dev_hold(dev);
601 ip_rt_put(rt);
603 return dev;
605 #else
606 static struct net_device *inet_fib_lookup_dev(struct net *net,
607 const void *addr)
609 return ERR_PTR(-EAFNOSUPPORT);
611 #endif
613 #if IS_ENABLED(CONFIG_IPV6)
614 static struct net_device *inet6_fib_lookup_dev(struct net *net,
615 const void *addr)
617 struct net_device *dev;
618 struct dst_entry *dst;
619 struct flowi6 fl6;
620 int err;
622 if (!ipv6_stub)
623 return ERR_PTR(-EAFNOSUPPORT);
625 memset(&fl6, 0, sizeof(fl6));
626 memcpy(&fl6.daddr, addr, sizeof(struct in6_addr));
627 err = ipv6_stub->ipv6_dst_lookup(net, NULL, &dst, &fl6);
628 if (err)
629 return ERR_PTR(err);
631 dev = dst->dev;
632 dev_hold(dev);
633 dst_release(dst);
635 return dev;
637 #else
638 static struct net_device *inet6_fib_lookup_dev(struct net *net,
639 const void *addr)
641 return ERR_PTR(-EAFNOSUPPORT);
643 #endif
645 static struct net_device *find_outdev(struct net *net,
646 struct mpls_route *rt,
647 struct mpls_nh *nh, int oif)
649 struct net_device *dev = NULL;
651 if (!oif) {
652 switch (nh->nh_via_table) {
653 case NEIGH_ARP_TABLE:
654 dev = inet_fib_lookup_dev(net, mpls_nh_via(rt, nh));
655 break;
656 case NEIGH_ND_TABLE:
657 dev = inet6_fib_lookup_dev(net, mpls_nh_via(rt, nh));
658 break;
659 case NEIGH_LINK_TABLE:
660 break;
662 } else {
663 dev = dev_get_by_index(net, oif);
666 if (!dev)
667 return ERR_PTR(-ENODEV);
669 if (IS_ERR(dev))
670 return dev;
672 /* The caller is holding rtnl anyways, so release the dev reference */
673 dev_put(dev);
675 return dev;
678 static int mpls_nh_assign_dev(struct net *net, struct mpls_route *rt,
679 struct mpls_nh *nh, int oif)
681 struct net_device *dev = NULL;
682 int err = -ENODEV;
684 dev = find_outdev(net, rt, nh, oif);
685 if (IS_ERR(dev)) {
686 err = PTR_ERR(dev);
687 dev = NULL;
688 goto errout;
691 /* Ensure this is a supported device */
692 err = -EINVAL;
693 if (!mpls_dev_get(dev))
694 goto errout;
696 if ((nh->nh_via_table == NEIGH_LINK_TABLE) &&
697 (dev->addr_len != nh->nh_via_alen))
698 goto errout;
700 RCU_INIT_POINTER(nh->nh_dev, dev);
702 if (!(dev->flags & IFF_UP)) {
703 nh->nh_flags |= RTNH_F_DEAD;
704 } else {
705 unsigned int flags;
707 flags = dev_get_flags(dev);
708 if (!(flags & (IFF_RUNNING | IFF_LOWER_UP)))
709 nh->nh_flags |= RTNH_F_LINKDOWN;
712 return 0;
714 errout:
715 return err;
718 static int nla_get_via(const struct nlattr *nla, u8 *via_alen, u8 *via_table,
719 u8 via_addr[], struct netlink_ext_ack *extack)
721 struct rtvia *via = nla_data(nla);
722 int err = -EINVAL;
723 int alen;
725 if (nla_len(nla) < offsetof(struct rtvia, rtvia_addr)) {
726 NL_SET_ERR_MSG_ATTR(extack, nla,
727 "Invalid attribute length for RTA_VIA");
728 goto errout;
730 alen = nla_len(nla) -
731 offsetof(struct rtvia, rtvia_addr);
732 if (alen > MAX_VIA_ALEN) {
733 NL_SET_ERR_MSG_ATTR(extack, nla,
734 "Invalid address length for RTA_VIA");
735 goto errout;
738 /* Validate the address family */
739 switch (via->rtvia_family) {
740 case AF_PACKET:
741 *via_table = NEIGH_LINK_TABLE;
742 break;
743 case AF_INET:
744 *via_table = NEIGH_ARP_TABLE;
745 if (alen != 4)
746 goto errout;
747 break;
748 case AF_INET6:
749 *via_table = NEIGH_ND_TABLE;
750 if (alen != 16)
751 goto errout;
752 break;
753 default:
754 /* Unsupported address family */
755 goto errout;
758 memcpy(via_addr, via->rtvia_addr, alen);
759 *via_alen = alen;
760 err = 0;
762 errout:
763 return err;
766 static int mpls_nh_build_from_cfg(struct mpls_route_config *cfg,
767 struct mpls_route *rt)
769 struct net *net = cfg->rc_nlinfo.nl_net;
770 struct mpls_nh *nh = rt->rt_nh;
771 int err;
772 int i;
774 if (!nh)
775 return -ENOMEM;
777 nh->nh_labels = cfg->rc_output_labels;
778 for (i = 0; i < nh->nh_labels; i++)
779 nh->nh_label[i] = cfg->rc_output_label[i];
781 nh->nh_via_table = cfg->rc_via_table;
782 memcpy(__mpls_nh_via(rt, nh), cfg->rc_via, cfg->rc_via_alen);
783 nh->nh_via_alen = cfg->rc_via_alen;
785 err = mpls_nh_assign_dev(net, rt, nh, cfg->rc_ifindex);
786 if (err)
787 goto errout;
789 if (nh->nh_flags & (RTNH_F_DEAD | RTNH_F_LINKDOWN))
790 rt->rt_nhn_alive--;
792 return 0;
794 errout:
795 return err;
798 static int mpls_nh_build(struct net *net, struct mpls_route *rt,
799 struct mpls_nh *nh, int oif, struct nlattr *via,
800 struct nlattr *newdst, u8 max_labels,
801 struct netlink_ext_ack *extack)
803 int err = -ENOMEM;
805 if (!nh)
806 goto errout;
808 if (newdst) {
809 err = nla_get_labels(newdst, max_labels, &nh->nh_labels,
810 nh->nh_label, extack);
811 if (err)
812 goto errout;
815 if (via) {
816 err = nla_get_via(via, &nh->nh_via_alen, &nh->nh_via_table,
817 __mpls_nh_via(rt, nh), extack);
818 if (err)
819 goto errout;
820 } else {
821 nh->nh_via_table = MPLS_NEIGH_TABLE_UNSPEC;
824 err = mpls_nh_assign_dev(net, rt, nh, oif);
825 if (err)
826 goto errout;
828 return 0;
830 errout:
831 return err;
834 static u8 mpls_count_nexthops(struct rtnexthop *rtnh, int len,
835 u8 cfg_via_alen, u8 *max_via_alen,
836 u8 *max_labels)
838 int remaining = len;
839 u8 nhs = 0;
841 *max_via_alen = 0;
842 *max_labels = 0;
844 while (rtnh_ok(rtnh, remaining)) {
845 struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
846 int attrlen;
847 u8 n_labels = 0;
849 attrlen = rtnh_attrlen(rtnh);
850 nla = nla_find(attrs, attrlen, RTA_VIA);
851 if (nla && nla_len(nla) >=
852 offsetof(struct rtvia, rtvia_addr)) {
853 int via_alen = nla_len(nla) -
854 offsetof(struct rtvia, rtvia_addr);
856 if (via_alen <= MAX_VIA_ALEN)
857 *max_via_alen = max_t(u16, *max_via_alen,
858 via_alen);
861 nla = nla_find(attrs, attrlen, RTA_NEWDST);
862 if (nla &&
863 nla_get_labels(nla, MAX_NEW_LABELS, &n_labels,
864 NULL, NULL) != 0)
865 return 0;
867 *max_labels = max_t(u8, *max_labels, n_labels);
869 /* number of nexthops is tracked by a u8.
870 * Check for overflow.
872 if (nhs == 255)
873 return 0;
874 nhs++;
876 rtnh = rtnh_next(rtnh, &remaining);
879 /* leftover implies invalid nexthop configuration, discard it */
880 return remaining > 0 ? 0 : nhs;
883 static int mpls_nh_build_multi(struct mpls_route_config *cfg,
884 struct mpls_route *rt, u8 max_labels,
885 struct netlink_ext_ack *extack)
887 struct rtnexthop *rtnh = cfg->rc_mp;
888 struct nlattr *nla_via, *nla_newdst;
889 int remaining = cfg->rc_mp_len;
890 int err = 0;
891 u8 nhs = 0;
893 change_nexthops(rt) {
894 int attrlen;
896 nla_via = NULL;
897 nla_newdst = NULL;
899 err = -EINVAL;
900 if (!rtnh_ok(rtnh, remaining))
901 goto errout;
903 /* neither weighted multipath nor any flags
904 * are supported
906 if (rtnh->rtnh_hops || rtnh->rtnh_flags)
907 goto errout;
909 attrlen = rtnh_attrlen(rtnh);
910 if (attrlen > 0) {
911 struct nlattr *attrs = rtnh_attrs(rtnh);
913 nla_via = nla_find(attrs, attrlen, RTA_VIA);
914 nla_newdst = nla_find(attrs, attrlen, RTA_NEWDST);
917 err = mpls_nh_build(cfg->rc_nlinfo.nl_net, rt, nh,
918 rtnh->rtnh_ifindex, nla_via, nla_newdst,
919 max_labels, extack);
920 if (err)
921 goto errout;
923 if (nh->nh_flags & (RTNH_F_DEAD | RTNH_F_LINKDOWN))
924 rt->rt_nhn_alive--;
926 rtnh = rtnh_next(rtnh, &remaining);
927 nhs++;
928 } endfor_nexthops(rt);
930 rt->rt_nhn = nhs;
932 return 0;
934 errout:
935 return err;
938 static bool mpls_label_ok(struct net *net, unsigned int *index,
939 struct netlink_ext_ack *extack)
941 bool is_ok = true;
943 /* Reserved labels may not be set */
944 if (*index < MPLS_LABEL_FIRST_UNRESERVED) {
945 NL_SET_ERR_MSG(extack,
946 "Invalid label - must be MPLS_LABEL_FIRST_UNRESERVED or higher");
947 is_ok = false;
950 /* The full 20 bit range may not be supported. */
951 if (is_ok && *index >= net->mpls.platform_labels) {
952 NL_SET_ERR_MSG(extack,
953 "Label >= configured maximum in platform_labels");
954 is_ok = false;
957 *index = array_index_nospec(*index, net->mpls.platform_labels);
958 return is_ok;
961 static int mpls_route_add(struct mpls_route_config *cfg,
962 struct netlink_ext_ack *extack)
964 struct mpls_route __rcu **platform_label;
965 struct net *net = cfg->rc_nlinfo.nl_net;
966 struct mpls_route *rt, *old;
967 int err = -EINVAL;
968 u8 max_via_alen;
969 unsigned index;
970 u8 max_labels;
971 u8 nhs;
973 index = cfg->rc_label;
975 /* If a label was not specified during insert pick one */
976 if ((index == LABEL_NOT_SPECIFIED) &&
977 (cfg->rc_nlflags & NLM_F_CREATE)) {
978 index = find_free_label(net);
981 if (!mpls_label_ok(net, &index, extack))
982 goto errout;
984 /* Append makes no sense with mpls */
985 err = -EOPNOTSUPP;
986 if (cfg->rc_nlflags & NLM_F_APPEND) {
987 NL_SET_ERR_MSG(extack, "MPLS does not support route append");
988 goto errout;
991 err = -EEXIST;
992 platform_label = rtnl_dereference(net->mpls.platform_label);
993 old = rtnl_dereference(platform_label[index]);
994 if ((cfg->rc_nlflags & NLM_F_EXCL) && old)
995 goto errout;
997 err = -EEXIST;
998 if (!(cfg->rc_nlflags & NLM_F_REPLACE) && old)
999 goto errout;
1001 err = -ENOENT;
1002 if (!(cfg->rc_nlflags & NLM_F_CREATE) && !old)
1003 goto errout;
1005 err = -EINVAL;
1006 if (cfg->rc_mp) {
1007 nhs = mpls_count_nexthops(cfg->rc_mp, cfg->rc_mp_len,
1008 cfg->rc_via_alen, &max_via_alen,
1009 &max_labels);
1010 } else {
1011 max_via_alen = cfg->rc_via_alen;
1012 max_labels = cfg->rc_output_labels;
1013 nhs = 1;
1016 if (nhs == 0) {
1017 NL_SET_ERR_MSG(extack, "Route does not contain a nexthop");
1018 goto errout;
1021 err = -ENOMEM;
1022 rt = mpls_rt_alloc(nhs, max_via_alen, max_labels);
1023 if (IS_ERR(rt)) {
1024 err = PTR_ERR(rt);
1025 goto errout;
1028 rt->rt_protocol = cfg->rc_protocol;
1029 rt->rt_payload_type = cfg->rc_payload_type;
1030 rt->rt_ttl_propagate = cfg->rc_ttl_propagate;
1032 if (cfg->rc_mp)
1033 err = mpls_nh_build_multi(cfg, rt, max_labels, extack);
1034 else
1035 err = mpls_nh_build_from_cfg(cfg, rt);
1036 if (err)
1037 goto freert;
1039 mpls_route_update(net, index, rt, &cfg->rc_nlinfo);
1041 return 0;
1043 freert:
1044 mpls_rt_free(rt);
1045 errout:
1046 return err;
1049 static int mpls_route_del(struct mpls_route_config *cfg,
1050 struct netlink_ext_ack *extack)
1052 struct net *net = cfg->rc_nlinfo.nl_net;
1053 unsigned index;
1054 int err = -EINVAL;
1056 index = cfg->rc_label;
1058 if (!mpls_label_ok(net, &index, extack))
1059 goto errout;
1061 mpls_route_update(net, index, NULL, &cfg->rc_nlinfo);
1063 err = 0;
1064 errout:
1065 return err;
1068 static void mpls_get_stats(struct mpls_dev *mdev,
1069 struct mpls_link_stats *stats)
1071 struct mpls_pcpu_stats *p;
1072 int i;
1074 memset(stats, 0, sizeof(*stats));
1076 for_each_possible_cpu(i) {
1077 struct mpls_link_stats local;
1078 unsigned int start;
1080 p = per_cpu_ptr(mdev->stats, i);
1081 do {
1082 start = u64_stats_fetch_begin(&p->syncp);
1083 local = p->stats;
1084 } while (u64_stats_fetch_retry(&p->syncp, start));
1086 stats->rx_packets += local.rx_packets;
1087 stats->rx_bytes += local.rx_bytes;
1088 stats->tx_packets += local.tx_packets;
1089 stats->tx_bytes += local.tx_bytes;
1090 stats->rx_errors += local.rx_errors;
1091 stats->tx_errors += local.tx_errors;
1092 stats->rx_dropped += local.rx_dropped;
1093 stats->tx_dropped += local.tx_dropped;
1094 stats->rx_noroute += local.rx_noroute;
1098 static int mpls_fill_stats_af(struct sk_buff *skb,
1099 const struct net_device *dev)
1101 struct mpls_link_stats *stats;
1102 struct mpls_dev *mdev;
1103 struct nlattr *nla;
1105 mdev = mpls_dev_get(dev);
1106 if (!mdev)
1107 return -ENODATA;
1109 nla = nla_reserve_64bit(skb, MPLS_STATS_LINK,
1110 sizeof(struct mpls_link_stats),
1111 MPLS_STATS_UNSPEC);
1112 if (!nla)
1113 return -EMSGSIZE;
1115 stats = nla_data(nla);
1116 mpls_get_stats(mdev, stats);
1118 return 0;
1121 static size_t mpls_get_stats_af_size(const struct net_device *dev)
1123 struct mpls_dev *mdev;
1125 mdev = mpls_dev_get(dev);
1126 if (!mdev)
1127 return 0;
1129 return nla_total_size_64bit(sizeof(struct mpls_link_stats));
1132 static int mpls_netconf_fill_devconf(struct sk_buff *skb, struct mpls_dev *mdev,
1133 u32 portid, u32 seq, int event,
1134 unsigned int flags, int type)
1136 struct nlmsghdr *nlh;
1137 struct netconfmsg *ncm;
1138 bool all = false;
1140 nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
1141 flags);
1142 if (!nlh)
1143 return -EMSGSIZE;
1145 if (type == NETCONFA_ALL)
1146 all = true;
1148 ncm = nlmsg_data(nlh);
1149 ncm->ncm_family = AF_MPLS;
1151 if (nla_put_s32(skb, NETCONFA_IFINDEX, mdev->dev->ifindex) < 0)
1152 goto nla_put_failure;
1154 if ((all || type == NETCONFA_INPUT) &&
1155 nla_put_s32(skb, NETCONFA_INPUT,
1156 mdev->input_enabled) < 0)
1157 goto nla_put_failure;
1159 nlmsg_end(skb, nlh);
1160 return 0;
1162 nla_put_failure:
1163 nlmsg_cancel(skb, nlh);
1164 return -EMSGSIZE;
1167 static int mpls_netconf_msgsize_devconf(int type)
1169 int size = NLMSG_ALIGN(sizeof(struct netconfmsg))
1170 + nla_total_size(4); /* NETCONFA_IFINDEX */
1171 bool all = false;
1173 if (type == NETCONFA_ALL)
1174 all = true;
1176 if (all || type == NETCONFA_INPUT)
1177 size += nla_total_size(4);
1179 return size;
1182 static void mpls_netconf_notify_devconf(struct net *net, int event,
1183 int type, struct mpls_dev *mdev)
1185 struct sk_buff *skb;
1186 int err = -ENOBUFS;
1188 skb = nlmsg_new(mpls_netconf_msgsize_devconf(type), GFP_KERNEL);
1189 if (!skb)
1190 goto errout;
1192 err = mpls_netconf_fill_devconf(skb, mdev, 0, 0, event, 0, type);
1193 if (err < 0) {
1194 /* -EMSGSIZE implies BUG in mpls_netconf_msgsize_devconf() */
1195 WARN_ON(err == -EMSGSIZE);
1196 kfree_skb(skb);
1197 goto errout;
1200 rtnl_notify(skb, net, 0, RTNLGRP_MPLS_NETCONF, NULL, GFP_KERNEL);
1201 return;
1202 errout:
1203 if (err < 0)
1204 rtnl_set_sk_err(net, RTNLGRP_MPLS_NETCONF, err);
1207 static const struct nla_policy devconf_mpls_policy[NETCONFA_MAX + 1] = {
1208 [NETCONFA_IFINDEX] = { .len = sizeof(int) },
1211 static int mpls_netconf_valid_get_req(struct sk_buff *skb,
1212 const struct nlmsghdr *nlh,
1213 struct nlattr **tb,
1214 struct netlink_ext_ack *extack)
1216 int i, err;
1218 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(struct netconfmsg))) {
1219 NL_SET_ERR_MSG_MOD(extack,
1220 "Invalid header for netconf get request");
1221 return -EINVAL;
1224 if (!netlink_strict_get_check(skb))
1225 return nlmsg_parse_deprecated(nlh, sizeof(struct netconfmsg),
1226 tb, NETCONFA_MAX,
1227 devconf_mpls_policy, extack);
1229 err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct netconfmsg),
1230 tb, NETCONFA_MAX,
1231 devconf_mpls_policy, extack);
1232 if (err)
1233 return err;
1235 for (i = 0; i <= NETCONFA_MAX; i++) {
1236 if (!tb[i])
1237 continue;
1239 switch (i) {
1240 case NETCONFA_IFINDEX:
1241 break;
1242 default:
1243 NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in netconf get request");
1244 return -EINVAL;
1248 return 0;
1251 static int mpls_netconf_get_devconf(struct sk_buff *in_skb,
1252 struct nlmsghdr *nlh,
1253 struct netlink_ext_ack *extack)
1255 struct net *net = sock_net(in_skb->sk);
1256 struct nlattr *tb[NETCONFA_MAX + 1];
1257 struct net_device *dev;
1258 struct mpls_dev *mdev;
1259 struct sk_buff *skb;
1260 int ifindex;
1261 int err;
1263 err = mpls_netconf_valid_get_req(in_skb, nlh, tb, extack);
1264 if (err < 0)
1265 goto errout;
1267 err = -EINVAL;
1268 if (!tb[NETCONFA_IFINDEX])
1269 goto errout;
1271 ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
1272 dev = __dev_get_by_index(net, ifindex);
1273 if (!dev)
1274 goto errout;
1276 mdev = mpls_dev_get(dev);
1277 if (!mdev)
1278 goto errout;
1280 err = -ENOBUFS;
1281 skb = nlmsg_new(mpls_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL);
1282 if (!skb)
1283 goto errout;
1285 err = mpls_netconf_fill_devconf(skb, mdev,
1286 NETLINK_CB(in_skb).portid,
1287 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
1288 NETCONFA_ALL);
1289 if (err < 0) {
1290 /* -EMSGSIZE implies BUG in mpls_netconf_msgsize_devconf() */
1291 WARN_ON(err == -EMSGSIZE);
1292 kfree_skb(skb);
1293 goto errout;
1295 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
1296 errout:
1297 return err;
1300 static int mpls_netconf_dump_devconf(struct sk_buff *skb,
1301 struct netlink_callback *cb)
1303 const struct nlmsghdr *nlh = cb->nlh;
1304 struct net *net = sock_net(skb->sk);
1305 struct hlist_head *head;
1306 struct net_device *dev;
1307 struct mpls_dev *mdev;
1308 int idx, s_idx;
1309 int h, s_h;
1311 if (cb->strict_check) {
1312 struct netlink_ext_ack *extack = cb->extack;
1313 struct netconfmsg *ncm;
1315 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ncm))) {
1316 NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf dump request");
1317 return -EINVAL;
1320 if (nlmsg_attrlen(nlh, sizeof(*ncm))) {
1321 NL_SET_ERR_MSG_MOD(extack, "Invalid data after header in netconf dump request");
1322 return -EINVAL;
1326 s_h = cb->args[0];
1327 s_idx = idx = cb->args[1];
1329 for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
1330 idx = 0;
1331 head = &net->dev_index_head[h];
1332 rcu_read_lock();
1333 cb->seq = net->dev_base_seq;
1334 hlist_for_each_entry_rcu(dev, head, index_hlist) {
1335 if (idx < s_idx)
1336 goto cont;
1337 mdev = mpls_dev_get(dev);
1338 if (!mdev)
1339 goto cont;
1340 if (mpls_netconf_fill_devconf(skb, mdev,
1341 NETLINK_CB(cb->skb).portid,
1342 nlh->nlmsg_seq,
1343 RTM_NEWNETCONF,
1344 NLM_F_MULTI,
1345 NETCONFA_ALL) < 0) {
1346 rcu_read_unlock();
1347 goto done;
1349 nl_dump_check_consistent(cb, nlmsg_hdr(skb));
1350 cont:
1351 idx++;
1353 rcu_read_unlock();
1355 done:
1356 cb->args[0] = h;
1357 cb->args[1] = idx;
1359 return skb->len;
1362 #define MPLS_PERDEV_SYSCTL_OFFSET(field) \
1363 (&((struct mpls_dev *)0)->field)
1365 static int mpls_conf_proc(struct ctl_table *ctl, int write,
1366 void __user *buffer,
1367 size_t *lenp, loff_t *ppos)
1369 int oval = *(int *)ctl->data;
1370 int ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
1372 if (write) {
1373 struct mpls_dev *mdev = ctl->extra1;
1374 int i = (int *)ctl->data - (int *)mdev;
1375 struct net *net = ctl->extra2;
1376 int val = *(int *)ctl->data;
1378 if (i == offsetof(struct mpls_dev, input_enabled) &&
1379 val != oval) {
1380 mpls_netconf_notify_devconf(net, RTM_NEWNETCONF,
1381 NETCONFA_INPUT, mdev);
1385 return ret;
1388 static const struct ctl_table mpls_dev_table[] = {
1390 .procname = "input",
1391 .maxlen = sizeof(int),
1392 .mode = 0644,
1393 .proc_handler = mpls_conf_proc,
1394 .data = MPLS_PERDEV_SYSCTL_OFFSET(input_enabled),
1399 static int mpls_dev_sysctl_register(struct net_device *dev,
1400 struct mpls_dev *mdev)
1402 char path[sizeof("net/mpls/conf/") + IFNAMSIZ];
1403 struct net *net = dev_net(dev);
1404 struct ctl_table *table;
1405 int i;
1407 table = kmemdup(&mpls_dev_table, sizeof(mpls_dev_table), GFP_KERNEL);
1408 if (!table)
1409 goto out;
1411 /* Table data contains only offsets relative to the base of
1412 * the mdev at this point, so make them absolute.
1414 for (i = 0; i < ARRAY_SIZE(mpls_dev_table); i++) {
1415 table[i].data = (char *)mdev + (uintptr_t)table[i].data;
1416 table[i].extra1 = mdev;
1417 table[i].extra2 = net;
1420 snprintf(path, sizeof(path), "net/mpls/conf/%s", dev->name);
1422 mdev->sysctl = register_net_sysctl(net, path, table);
1423 if (!mdev->sysctl)
1424 goto free;
1426 mpls_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL, mdev);
1427 return 0;
1429 free:
1430 kfree(table);
1431 out:
1432 return -ENOBUFS;
1435 static void mpls_dev_sysctl_unregister(struct net_device *dev,
1436 struct mpls_dev *mdev)
1438 struct net *net = dev_net(dev);
1439 struct ctl_table *table;
1441 table = mdev->sysctl->ctl_table_arg;
1442 unregister_net_sysctl_table(mdev->sysctl);
1443 kfree(table);
1445 mpls_netconf_notify_devconf(net, RTM_DELNETCONF, 0, mdev);
1448 static struct mpls_dev *mpls_add_dev(struct net_device *dev)
1450 struct mpls_dev *mdev;
1451 int err = -ENOMEM;
1452 int i;
1454 ASSERT_RTNL();
1456 mdev = kzalloc(sizeof(*mdev), GFP_KERNEL);
1457 if (!mdev)
1458 return ERR_PTR(err);
1460 mdev->stats = alloc_percpu(struct mpls_pcpu_stats);
1461 if (!mdev->stats)
1462 goto free;
1464 for_each_possible_cpu(i) {
1465 struct mpls_pcpu_stats *mpls_stats;
1467 mpls_stats = per_cpu_ptr(mdev->stats, i);
1468 u64_stats_init(&mpls_stats->syncp);
1471 mdev->dev = dev;
1473 err = mpls_dev_sysctl_register(dev, mdev);
1474 if (err)
1475 goto free;
1477 rcu_assign_pointer(dev->mpls_ptr, mdev);
1479 return mdev;
1481 free:
1482 free_percpu(mdev->stats);
1483 kfree(mdev);
1484 return ERR_PTR(err);
1487 static void mpls_dev_destroy_rcu(struct rcu_head *head)
1489 struct mpls_dev *mdev = container_of(head, struct mpls_dev, rcu);
1491 free_percpu(mdev->stats);
1492 kfree(mdev);
1495 static void mpls_ifdown(struct net_device *dev, int event)
1497 struct mpls_route __rcu **platform_label;
1498 struct net *net = dev_net(dev);
1499 u8 alive, deleted;
1500 unsigned index;
1502 platform_label = rtnl_dereference(net->mpls.platform_label);
1503 for (index = 0; index < net->mpls.platform_labels; index++) {
1504 struct mpls_route *rt = rtnl_dereference(platform_label[index]);
1506 if (!rt)
1507 continue;
1509 alive = 0;
1510 deleted = 0;
1511 change_nexthops(rt) {
1512 unsigned int nh_flags = nh->nh_flags;
1514 if (rtnl_dereference(nh->nh_dev) != dev)
1515 goto next;
1517 switch (event) {
1518 case NETDEV_DOWN:
1519 case NETDEV_UNREGISTER:
1520 nh_flags |= RTNH_F_DEAD;
1521 /* fall through */
1522 case NETDEV_CHANGE:
1523 nh_flags |= RTNH_F_LINKDOWN;
1524 break;
1526 if (event == NETDEV_UNREGISTER)
1527 RCU_INIT_POINTER(nh->nh_dev, NULL);
1529 if (nh->nh_flags != nh_flags)
1530 WRITE_ONCE(nh->nh_flags, nh_flags);
1531 next:
1532 if (!(nh_flags & (RTNH_F_DEAD | RTNH_F_LINKDOWN)))
1533 alive++;
1534 if (!rtnl_dereference(nh->nh_dev))
1535 deleted++;
1536 } endfor_nexthops(rt);
1538 WRITE_ONCE(rt->rt_nhn_alive, alive);
1540 /* if there are no more nexthops, delete the route */
1541 if (event == NETDEV_UNREGISTER && deleted == rt->rt_nhn)
1542 mpls_route_update(net, index, NULL, NULL);
1546 static void mpls_ifup(struct net_device *dev, unsigned int flags)
1548 struct mpls_route __rcu **platform_label;
1549 struct net *net = dev_net(dev);
1550 unsigned index;
1551 u8 alive;
1553 platform_label = rtnl_dereference(net->mpls.platform_label);
1554 for (index = 0; index < net->mpls.platform_labels; index++) {
1555 struct mpls_route *rt = rtnl_dereference(platform_label[index]);
1557 if (!rt)
1558 continue;
1560 alive = 0;
1561 change_nexthops(rt) {
1562 unsigned int nh_flags = nh->nh_flags;
1563 struct net_device *nh_dev =
1564 rtnl_dereference(nh->nh_dev);
1566 if (!(nh_flags & flags)) {
1567 alive++;
1568 continue;
1570 if (nh_dev != dev)
1571 continue;
1572 alive++;
1573 nh_flags &= ~flags;
1574 WRITE_ONCE(nh->nh_flags, nh_flags);
1575 } endfor_nexthops(rt);
1577 WRITE_ONCE(rt->rt_nhn_alive, alive);
1581 static int mpls_dev_notify(struct notifier_block *this, unsigned long event,
1582 void *ptr)
1584 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1585 struct mpls_dev *mdev;
1586 unsigned int flags;
1588 if (event == NETDEV_REGISTER) {
1590 /* For now just support Ethernet, IPGRE, IP6GRE, SIT and
1591 * IPIP devices
1593 if (dev->type == ARPHRD_ETHER ||
1594 dev->type == ARPHRD_LOOPBACK ||
1595 dev->type == ARPHRD_IPGRE ||
1596 dev->type == ARPHRD_IP6GRE ||
1597 dev->type == ARPHRD_SIT ||
1598 dev->type == ARPHRD_TUNNEL) {
1599 mdev = mpls_add_dev(dev);
1600 if (IS_ERR(mdev))
1601 return notifier_from_errno(PTR_ERR(mdev));
1603 return NOTIFY_OK;
1606 mdev = mpls_dev_get(dev);
1607 if (!mdev)
1608 return NOTIFY_OK;
1610 switch (event) {
1611 case NETDEV_DOWN:
1612 mpls_ifdown(dev, event);
1613 break;
1614 case NETDEV_UP:
1615 flags = dev_get_flags(dev);
1616 if (flags & (IFF_RUNNING | IFF_LOWER_UP))
1617 mpls_ifup(dev, RTNH_F_DEAD | RTNH_F_LINKDOWN);
1618 else
1619 mpls_ifup(dev, RTNH_F_DEAD);
1620 break;
1621 case NETDEV_CHANGE:
1622 flags = dev_get_flags(dev);
1623 if (flags & (IFF_RUNNING | IFF_LOWER_UP))
1624 mpls_ifup(dev, RTNH_F_DEAD | RTNH_F_LINKDOWN);
1625 else
1626 mpls_ifdown(dev, event);
1627 break;
1628 case NETDEV_UNREGISTER:
1629 mpls_ifdown(dev, event);
1630 mdev = mpls_dev_get(dev);
1631 if (mdev) {
1632 mpls_dev_sysctl_unregister(dev, mdev);
1633 RCU_INIT_POINTER(dev->mpls_ptr, NULL);
1634 call_rcu(&mdev->rcu, mpls_dev_destroy_rcu);
1636 break;
1637 case NETDEV_CHANGENAME:
1638 mdev = mpls_dev_get(dev);
1639 if (mdev) {
1640 int err;
1642 mpls_dev_sysctl_unregister(dev, mdev);
1643 err = mpls_dev_sysctl_register(dev, mdev);
1644 if (err)
1645 return notifier_from_errno(err);
1647 break;
1649 return NOTIFY_OK;
1652 static struct notifier_block mpls_dev_notifier = {
1653 .notifier_call = mpls_dev_notify,
1656 static int nla_put_via(struct sk_buff *skb,
1657 u8 table, const void *addr, int alen)
1659 static const int table_to_family[NEIGH_NR_TABLES + 1] = {
1660 AF_INET, AF_INET6, AF_DECnet, AF_PACKET,
1662 struct nlattr *nla;
1663 struct rtvia *via;
1664 int family = AF_UNSPEC;
1666 nla = nla_reserve(skb, RTA_VIA, alen + 2);
1667 if (!nla)
1668 return -EMSGSIZE;
1670 if (table <= NEIGH_NR_TABLES)
1671 family = table_to_family[table];
1673 via = nla_data(nla);
1674 via->rtvia_family = family;
1675 memcpy(via->rtvia_addr, addr, alen);
1676 return 0;
1679 int nla_put_labels(struct sk_buff *skb, int attrtype,
1680 u8 labels, const u32 label[])
1682 struct nlattr *nla;
1683 struct mpls_shim_hdr *nla_label;
1684 bool bos;
1685 int i;
1686 nla = nla_reserve(skb, attrtype, labels*4);
1687 if (!nla)
1688 return -EMSGSIZE;
1690 nla_label = nla_data(nla);
1691 bos = true;
1692 for (i = labels - 1; i >= 0; i--) {
1693 nla_label[i] = mpls_entry_encode(label[i], 0, 0, bos);
1694 bos = false;
1697 return 0;
1699 EXPORT_SYMBOL_GPL(nla_put_labels);
1701 int nla_get_labels(const struct nlattr *nla, u8 max_labels, u8 *labels,
1702 u32 label[], struct netlink_ext_ack *extack)
1704 unsigned len = nla_len(nla);
1705 struct mpls_shim_hdr *nla_label;
1706 u8 nla_labels;
1707 bool bos;
1708 int i;
1710 /* len needs to be an even multiple of 4 (the label size). Number
1711 * of labels is a u8 so check for overflow.
1713 if (len & 3 || len / 4 > 255) {
1714 NL_SET_ERR_MSG_ATTR(extack, nla,
1715 "Invalid length for labels attribute");
1716 return -EINVAL;
1719 /* Limit the number of new labels allowed */
1720 nla_labels = len/4;
1721 if (nla_labels > max_labels) {
1722 NL_SET_ERR_MSG(extack, "Too many labels");
1723 return -EINVAL;
1726 /* when label == NULL, caller wants number of labels */
1727 if (!label)
1728 goto out;
1730 nla_label = nla_data(nla);
1731 bos = true;
1732 for (i = nla_labels - 1; i >= 0; i--, bos = false) {
1733 struct mpls_entry_decoded dec;
1734 dec = mpls_entry_decode(nla_label + i);
1736 /* Ensure the bottom of stack flag is properly set
1737 * and ttl and tc are both clear.
1739 if (dec.ttl) {
1740 NL_SET_ERR_MSG_ATTR(extack, nla,
1741 "TTL in label must be 0");
1742 return -EINVAL;
1745 if (dec.tc) {
1746 NL_SET_ERR_MSG_ATTR(extack, nla,
1747 "Traffic class in label must be 0");
1748 return -EINVAL;
1751 if (dec.bos != bos) {
1752 NL_SET_BAD_ATTR(extack, nla);
1753 if (bos) {
1754 NL_SET_ERR_MSG(extack,
1755 "BOS bit must be set in first label");
1756 } else {
1757 NL_SET_ERR_MSG(extack,
1758 "BOS bit can only be set in first label");
1760 return -EINVAL;
1763 switch (dec.label) {
1764 case MPLS_LABEL_IMPLNULL:
1765 /* RFC3032: This is a label that an LSR may
1766 * assign and distribute, but which never
1767 * actually appears in the encapsulation.
1769 NL_SET_ERR_MSG_ATTR(extack, nla,
1770 "Implicit NULL Label (3) can not be used in encapsulation");
1771 return -EINVAL;
1774 label[i] = dec.label;
1776 out:
1777 *labels = nla_labels;
1778 return 0;
1780 EXPORT_SYMBOL_GPL(nla_get_labels);
1782 static int rtm_to_route_config(struct sk_buff *skb,
1783 struct nlmsghdr *nlh,
1784 struct mpls_route_config *cfg,
1785 struct netlink_ext_ack *extack)
1787 struct rtmsg *rtm;
1788 struct nlattr *tb[RTA_MAX+1];
1789 int index;
1790 int err;
1792 err = nlmsg_parse_deprecated(nlh, sizeof(*rtm), tb, RTA_MAX,
1793 rtm_mpls_policy, extack);
1794 if (err < 0)
1795 goto errout;
1797 err = -EINVAL;
1798 rtm = nlmsg_data(nlh);
1800 if (rtm->rtm_family != AF_MPLS) {
1801 NL_SET_ERR_MSG(extack, "Invalid address family in rtmsg");
1802 goto errout;
1804 if (rtm->rtm_dst_len != 20) {
1805 NL_SET_ERR_MSG(extack, "rtm_dst_len must be 20 for MPLS");
1806 goto errout;
1808 if (rtm->rtm_src_len != 0) {
1809 NL_SET_ERR_MSG(extack, "rtm_src_len must be 0 for MPLS");
1810 goto errout;
1812 if (rtm->rtm_tos != 0) {
1813 NL_SET_ERR_MSG(extack, "rtm_tos must be 0 for MPLS");
1814 goto errout;
1816 if (rtm->rtm_table != RT_TABLE_MAIN) {
1817 NL_SET_ERR_MSG(extack,
1818 "MPLS only supports the main route table");
1819 goto errout;
1821 /* Any value is acceptable for rtm_protocol */
1823 /* As mpls uses destination specific addresses
1824 * (or source specific address in the case of multicast)
1825 * all addresses have universal scope.
1827 if (rtm->rtm_scope != RT_SCOPE_UNIVERSE) {
1828 NL_SET_ERR_MSG(extack,
1829 "Invalid route scope - MPLS only supports UNIVERSE");
1830 goto errout;
1832 if (rtm->rtm_type != RTN_UNICAST) {
1833 NL_SET_ERR_MSG(extack,
1834 "Invalid route type - MPLS only supports UNICAST");
1835 goto errout;
1837 if (rtm->rtm_flags != 0) {
1838 NL_SET_ERR_MSG(extack, "rtm_flags must be 0 for MPLS");
1839 goto errout;
1842 cfg->rc_label = LABEL_NOT_SPECIFIED;
1843 cfg->rc_protocol = rtm->rtm_protocol;
1844 cfg->rc_via_table = MPLS_NEIGH_TABLE_UNSPEC;
1845 cfg->rc_ttl_propagate = MPLS_TTL_PROP_DEFAULT;
1846 cfg->rc_nlflags = nlh->nlmsg_flags;
1847 cfg->rc_nlinfo.portid = NETLINK_CB(skb).portid;
1848 cfg->rc_nlinfo.nlh = nlh;
1849 cfg->rc_nlinfo.nl_net = sock_net(skb->sk);
1851 for (index = 0; index <= RTA_MAX; index++) {
1852 struct nlattr *nla = tb[index];
1853 if (!nla)
1854 continue;
1856 switch (index) {
1857 case RTA_OIF:
1858 cfg->rc_ifindex = nla_get_u32(nla);
1859 break;
1860 case RTA_NEWDST:
1861 if (nla_get_labels(nla, MAX_NEW_LABELS,
1862 &cfg->rc_output_labels,
1863 cfg->rc_output_label, extack))
1864 goto errout;
1865 break;
1866 case RTA_DST:
1868 u8 label_count;
1869 if (nla_get_labels(nla, 1, &label_count,
1870 &cfg->rc_label, extack))
1871 goto errout;
1873 if (!mpls_label_ok(cfg->rc_nlinfo.nl_net,
1874 &cfg->rc_label, extack))
1875 goto errout;
1876 break;
1878 case RTA_GATEWAY:
1879 NL_SET_ERR_MSG(extack, "MPLS does not support RTA_GATEWAY attribute");
1880 goto errout;
1881 case RTA_VIA:
1883 if (nla_get_via(nla, &cfg->rc_via_alen,
1884 &cfg->rc_via_table, cfg->rc_via,
1885 extack))
1886 goto errout;
1887 break;
1889 case RTA_MULTIPATH:
1891 cfg->rc_mp = nla_data(nla);
1892 cfg->rc_mp_len = nla_len(nla);
1893 break;
1895 case RTA_TTL_PROPAGATE:
1897 u8 ttl_propagate = nla_get_u8(nla);
1899 if (ttl_propagate > 1) {
1900 NL_SET_ERR_MSG_ATTR(extack, nla,
1901 "RTA_TTL_PROPAGATE can only be 0 or 1");
1902 goto errout;
1904 cfg->rc_ttl_propagate = ttl_propagate ?
1905 MPLS_TTL_PROP_ENABLED :
1906 MPLS_TTL_PROP_DISABLED;
1907 break;
1909 default:
1910 NL_SET_ERR_MSG_ATTR(extack, nla, "Unknown attribute");
1911 /* Unsupported attribute */
1912 goto errout;
1916 err = 0;
1917 errout:
1918 return err;
1921 static int mpls_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh,
1922 struct netlink_ext_ack *extack)
1924 struct mpls_route_config *cfg;
1925 int err;
1927 cfg = kzalloc(sizeof(*cfg), GFP_KERNEL);
1928 if (!cfg)
1929 return -ENOMEM;
1931 err = rtm_to_route_config(skb, nlh, cfg, extack);
1932 if (err < 0)
1933 goto out;
1935 err = mpls_route_del(cfg, extack);
1936 out:
1937 kfree(cfg);
1939 return err;
1943 static int mpls_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh,
1944 struct netlink_ext_ack *extack)
1946 struct mpls_route_config *cfg;
1947 int err;
1949 cfg = kzalloc(sizeof(*cfg), GFP_KERNEL);
1950 if (!cfg)
1951 return -ENOMEM;
1953 err = rtm_to_route_config(skb, nlh, cfg, extack);
1954 if (err < 0)
1955 goto out;
1957 err = mpls_route_add(cfg, extack);
1958 out:
1959 kfree(cfg);
1961 return err;
1964 static int mpls_dump_route(struct sk_buff *skb, u32 portid, u32 seq, int event,
1965 u32 label, struct mpls_route *rt, int flags)
1967 struct net_device *dev;
1968 struct nlmsghdr *nlh;
1969 struct rtmsg *rtm;
1971 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*rtm), flags);
1972 if (nlh == NULL)
1973 return -EMSGSIZE;
1975 rtm = nlmsg_data(nlh);
1976 rtm->rtm_family = AF_MPLS;
1977 rtm->rtm_dst_len = 20;
1978 rtm->rtm_src_len = 0;
1979 rtm->rtm_tos = 0;
1980 rtm->rtm_table = RT_TABLE_MAIN;
1981 rtm->rtm_protocol = rt->rt_protocol;
1982 rtm->rtm_scope = RT_SCOPE_UNIVERSE;
1983 rtm->rtm_type = RTN_UNICAST;
1984 rtm->rtm_flags = 0;
1986 if (nla_put_labels(skb, RTA_DST, 1, &label))
1987 goto nla_put_failure;
1989 if (rt->rt_ttl_propagate != MPLS_TTL_PROP_DEFAULT) {
1990 bool ttl_propagate =
1991 rt->rt_ttl_propagate == MPLS_TTL_PROP_ENABLED;
1993 if (nla_put_u8(skb, RTA_TTL_PROPAGATE,
1994 ttl_propagate))
1995 goto nla_put_failure;
1997 if (rt->rt_nhn == 1) {
1998 const struct mpls_nh *nh = rt->rt_nh;
2000 if (nh->nh_labels &&
2001 nla_put_labels(skb, RTA_NEWDST, nh->nh_labels,
2002 nh->nh_label))
2003 goto nla_put_failure;
2004 if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC &&
2005 nla_put_via(skb, nh->nh_via_table, mpls_nh_via(rt, nh),
2006 nh->nh_via_alen))
2007 goto nla_put_failure;
2008 dev = rtnl_dereference(nh->nh_dev);
2009 if (dev && nla_put_u32(skb, RTA_OIF, dev->ifindex))
2010 goto nla_put_failure;
2011 if (nh->nh_flags & RTNH_F_LINKDOWN)
2012 rtm->rtm_flags |= RTNH_F_LINKDOWN;
2013 if (nh->nh_flags & RTNH_F_DEAD)
2014 rtm->rtm_flags |= RTNH_F_DEAD;
2015 } else {
2016 struct rtnexthop *rtnh;
2017 struct nlattr *mp;
2018 u8 linkdown = 0;
2019 u8 dead = 0;
2021 mp = nla_nest_start_noflag(skb, RTA_MULTIPATH);
2022 if (!mp)
2023 goto nla_put_failure;
2025 for_nexthops(rt) {
2026 dev = rtnl_dereference(nh->nh_dev);
2027 if (!dev)
2028 continue;
2030 rtnh = nla_reserve_nohdr(skb, sizeof(*rtnh));
2031 if (!rtnh)
2032 goto nla_put_failure;
2034 rtnh->rtnh_ifindex = dev->ifindex;
2035 if (nh->nh_flags & RTNH_F_LINKDOWN) {
2036 rtnh->rtnh_flags |= RTNH_F_LINKDOWN;
2037 linkdown++;
2039 if (nh->nh_flags & RTNH_F_DEAD) {
2040 rtnh->rtnh_flags |= RTNH_F_DEAD;
2041 dead++;
2044 if (nh->nh_labels && nla_put_labels(skb, RTA_NEWDST,
2045 nh->nh_labels,
2046 nh->nh_label))
2047 goto nla_put_failure;
2048 if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC &&
2049 nla_put_via(skb, nh->nh_via_table,
2050 mpls_nh_via(rt, nh),
2051 nh->nh_via_alen))
2052 goto nla_put_failure;
2054 /* length of rtnetlink header + attributes */
2055 rtnh->rtnh_len = nlmsg_get_pos(skb) - (void *)rtnh;
2056 } endfor_nexthops(rt);
2058 if (linkdown == rt->rt_nhn)
2059 rtm->rtm_flags |= RTNH_F_LINKDOWN;
2060 if (dead == rt->rt_nhn)
2061 rtm->rtm_flags |= RTNH_F_DEAD;
2063 nla_nest_end(skb, mp);
2066 nlmsg_end(skb, nlh);
2067 return 0;
2069 nla_put_failure:
2070 nlmsg_cancel(skb, nlh);
2071 return -EMSGSIZE;
2074 #if IS_ENABLED(CONFIG_INET)
2075 static int mpls_valid_fib_dump_req(struct net *net, const struct nlmsghdr *nlh,
2076 struct fib_dump_filter *filter,
2077 struct netlink_callback *cb)
2079 return ip_valid_fib_dump_req(net, nlh, filter, cb);
2081 #else
2082 static int mpls_valid_fib_dump_req(struct net *net, const struct nlmsghdr *nlh,
2083 struct fib_dump_filter *filter,
2084 struct netlink_callback *cb)
2086 struct netlink_ext_ack *extack = cb->extack;
2087 struct nlattr *tb[RTA_MAX + 1];
2088 struct rtmsg *rtm;
2089 int err, i;
2091 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*rtm))) {
2092 NL_SET_ERR_MSG_MOD(extack, "Invalid header for FIB dump request");
2093 return -EINVAL;
2096 rtm = nlmsg_data(nlh);
2097 if (rtm->rtm_dst_len || rtm->rtm_src_len || rtm->rtm_tos ||
2098 rtm->rtm_table || rtm->rtm_scope || rtm->rtm_type ||
2099 rtm->rtm_flags) {
2100 NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for FIB dump request");
2101 return -EINVAL;
2104 if (rtm->rtm_protocol) {
2105 filter->protocol = rtm->rtm_protocol;
2106 filter->filter_set = 1;
2107 cb->answer_flags = NLM_F_DUMP_FILTERED;
2110 err = nlmsg_parse_deprecated_strict(nlh, sizeof(*rtm), tb, RTA_MAX,
2111 rtm_mpls_policy, extack);
2112 if (err < 0)
2113 return err;
2115 for (i = 0; i <= RTA_MAX; ++i) {
2116 int ifindex;
2118 if (i == RTA_OIF) {
2119 ifindex = nla_get_u32(tb[i]);
2120 filter->dev = __dev_get_by_index(net, ifindex);
2121 if (!filter->dev)
2122 return -ENODEV;
2123 filter->filter_set = 1;
2124 } else if (tb[i]) {
2125 NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in dump request");
2126 return -EINVAL;
2130 return 0;
2132 #endif
2134 static bool mpls_rt_uses_dev(struct mpls_route *rt,
2135 const struct net_device *dev)
2137 struct net_device *nh_dev;
2139 if (rt->rt_nhn == 1) {
2140 struct mpls_nh *nh = rt->rt_nh;
2142 nh_dev = rtnl_dereference(nh->nh_dev);
2143 if (dev == nh_dev)
2144 return true;
2145 } else {
2146 for_nexthops(rt) {
2147 nh_dev = rtnl_dereference(nh->nh_dev);
2148 if (nh_dev == dev)
2149 return true;
2150 } endfor_nexthops(rt);
2153 return false;
2156 static int mpls_dump_routes(struct sk_buff *skb, struct netlink_callback *cb)
2158 const struct nlmsghdr *nlh = cb->nlh;
2159 struct net *net = sock_net(skb->sk);
2160 struct mpls_route __rcu **platform_label;
2161 struct fib_dump_filter filter = {};
2162 unsigned int flags = NLM_F_MULTI;
2163 size_t platform_labels;
2164 unsigned int index;
2166 ASSERT_RTNL();
2168 if (cb->strict_check) {
2169 int err;
2171 err = mpls_valid_fib_dump_req(net, nlh, &filter, cb);
2172 if (err < 0)
2173 return err;
2175 /* for MPLS, there is only 1 table with fixed type and flags.
2176 * If either are set in the filter then return nothing.
2178 if ((filter.table_id && filter.table_id != RT_TABLE_MAIN) ||
2179 (filter.rt_type && filter.rt_type != RTN_UNICAST) ||
2180 filter.flags)
2181 return skb->len;
2184 index = cb->args[0];
2185 if (index < MPLS_LABEL_FIRST_UNRESERVED)
2186 index = MPLS_LABEL_FIRST_UNRESERVED;
2188 platform_label = rtnl_dereference(net->mpls.platform_label);
2189 platform_labels = net->mpls.platform_labels;
2191 if (filter.filter_set)
2192 flags |= NLM_F_DUMP_FILTERED;
2194 for (; index < platform_labels; index++) {
2195 struct mpls_route *rt;
2197 rt = rtnl_dereference(platform_label[index]);
2198 if (!rt)
2199 continue;
2201 if ((filter.dev && !mpls_rt_uses_dev(rt, filter.dev)) ||
2202 (filter.protocol && rt->rt_protocol != filter.protocol))
2203 continue;
2205 if (mpls_dump_route(skb, NETLINK_CB(cb->skb).portid,
2206 cb->nlh->nlmsg_seq, RTM_NEWROUTE,
2207 index, rt, flags) < 0)
2208 break;
2210 cb->args[0] = index;
2212 return skb->len;
2215 static inline size_t lfib_nlmsg_size(struct mpls_route *rt)
2217 size_t payload =
2218 NLMSG_ALIGN(sizeof(struct rtmsg))
2219 + nla_total_size(4) /* RTA_DST */
2220 + nla_total_size(1); /* RTA_TTL_PROPAGATE */
2222 if (rt->rt_nhn == 1) {
2223 struct mpls_nh *nh = rt->rt_nh;
2225 if (nh->nh_dev)
2226 payload += nla_total_size(4); /* RTA_OIF */
2227 if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC) /* RTA_VIA */
2228 payload += nla_total_size(2 + nh->nh_via_alen);
2229 if (nh->nh_labels) /* RTA_NEWDST */
2230 payload += nla_total_size(nh->nh_labels * 4);
2231 } else {
2232 /* each nexthop is packed in an attribute */
2233 size_t nhsize = 0;
2235 for_nexthops(rt) {
2236 if (!rtnl_dereference(nh->nh_dev))
2237 continue;
2238 nhsize += nla_total_size(sizeof(struct rtnexthop));
2239 /* RTA_VIA */
2240 if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC)
2241 nhsize += nla_total_size(2 + nh->nh_via_alen);
2242 if (nh->nh_labels)
2243 nhsize += nla_total_size(nh->nh_labels * 4);
2244 } endfor_nexthops(rt);
2245 /* nested attribute */
2246 payload += nla_total_size(nhsize);
2249 return payload;
2252 static void rtmsg_lfib(int event, u32 label, struct mpls_route *rt,
2253 struct nlmsghdr *nlh, struct net *net, u32 portid,
2254 unsigned int nlm_flags)
2256 struct sk_buff *skb;
2257 u32 seq = nlh ? nlh->nlmsg_seq : 0;
2258 int err = -ENOBUFS;
2260 skb = nlmsg_new(lfib_nlmsg_size(rt), GFP_KERNEL);
2261 if (skb == NULL)
2262 goto errout;
2264 err = mpls_dump_route(skb, portid, seq, event, label, rt, nlm_flags);
2265 if (err < 0) {
2266 /* -EMSGSIZE implies BUG in lfib_nlmsg_size */
2267 WARN_ON(err == -EMSGSIZE);
2268 kfree_skb(skb);
2269 goto errout;
2271 rtnl_notify(skb, net, portid, RTNLGRP_MPLS_ROUTE, nlh, GFP_KERNEL);
2273 return;
2274 errout:
2275 if (err < 0)
2276 rtnl_set_sk_err(net, RTNLGRP_MPLS_ROUTE, err);
2279 static int mpls_valid_getroute_req(struct sk_buff *skb,
2280 const struct nlmsghdr *nlh,
2281 struct nlattr **tb,
2282 struct netlink_ext_ack *extack)
2284 struct rtmsg *rtm;
2285 int i, err;
2287 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*rtm))) {
2288 NL_SET_ERR_MSG_MOD(extack,
2289 "Invalid header for get route request");
2290 return -EINVAL;
2293 if (!netlink_strict_get_check(skb))
2294 return nlmsg_parse_deprecated(nlh, sizeof(*rtm), tb, RTA_MAX,
2295 rtm_mpls_policy, extack);
2297 rtm = nlmsg_data(nlh);
2298 if ((rtm->rtm_dst_len && rtm->rtm_dst_len != 20) ||
2299 rtm->rtm_src_len || rtm->rtm_tos || rtm->rtm_table ||
2300 rtm->rtm_protocol || rtm->rtm_scope || rtm->rtm_type) {
2301 NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for get route request");
2302 return -EINVAL;
2304 if (rtm->rtm_flags & ~RTM_F_FIB_MATCH) {
2305 NL_SET_ERR_MSG_MOD(extack,
2306 "Invalid flags for get route request");
2307 return -EINVAL;
2310 err = nlmsg_parse_deprecated_strict(nlh, sizeof(*rtm), tb, RTA_MAX,
2311 rtm_mpls_policy, extack);
2312 if (err)
2313 return err;
2315 if ((tb[RTA_DST] || tb[RTA_NEWDST]) && !rtm->rtm_dst_len) {
2316 NL_SET_ERR_MSG_MOD(extack, "rtm_dst_len must be 20 for MPLS");
2317 return -EINVAL;
2320 for (i = 0; i <= RTA_MAX; i++) {
2321 if (!tb[i])
2322 continue;
2324 switch (i) {
2325 case RTA_DST:
2326 case RTA_NEWDST:
2327 break;
2328 default:
2329 NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in get route request");
2330 return -EINVAL;
2334 return 0;
2337 static int mpls_getroute(struct sk_buff *in_skb, struct nlmsghdr *in_nlh,
2338 struct netlink_ext_ack *extack)
2340 struct net *net = sock_net(in_skb->sk);
2341 u32 portid = NETLINK_CB(in_skb).portid;
2342 u32 in_label = LABEL_NOT_SPECIFIED;
2343 struct nlattr *tb[RTA_MAX + 1];
2344 u32 labels[MAX_NEW_LABELS];
2345 struct mpls_shim_hdr *hdr;
2346 unsigned int hdr_size = 0;
2347 struct net_device *dev;
2348 struct mpls_route *rt;
2349 struct rtmsg *rtm, *r;
2350 struct nlmsghdr *nlh;
2351 struct sk_buff *skb;
2352 struct mpls_nh *nh;
2353 u8 n_labels;
2354 int err;
2356 err = mpls_valid_getroute_req(in_skb, in_nlh, tb, extack);
2357 if (err < 0)
2358 goto errout;
2360 rtm = nlmsg_data(in_nlh);
2362 if (tb[RTA_DST]) {
2363 u8 label_count;
2365 if (nla_get_labels(tb[RTA_DST], 1, &label_count,
2366 &in_label, extack)) {
2367 err = -EINVAL;
2368 goto errout;
2371 if (!mpls_label_ok(net, &in_label, extack)) {
2372 err = -EINVAL;
2373 goto errout;
2377 rt = mpls_route_input_rcu(net, in_label);
2378 if (!rt) {
2379 err = -ENETUNREACH;
2380 goto errout;
2383 if (rtm->rtm_flags & RTM_F_FIB_MATCH) {
2384 skb = nlmsg_new(lfib_nlmsg_size(rt), GFP_KERNEL);
2385 if (!skb) {
2386 err = -ENOBUFS;
2387 goto errout;
2390 err = mpls_dump_route(skb, portid, in_nlh->nlmsg_seq,
2391 RTM_NEWROUTE, in_label, rt, 0);
2392 if (err < 0) {
2393 /* -EMSGSIZE implies BUG in lfib_nlmsg_size */
2394 WARN_ON(err == -EMSGSIZE);
2395 goto errout_free;
2398 return rtnl_unicast(skb, net, portid);
2401 if (tb[RTA_NEWDST]) {
2402 if (nla_get_labels(tb[RTA_NEWDST], MAX_NEW_LABELS, &n_labels,
2403 labels, extack) != 0) {
2404 err = -EINVAL;
2405 goto errout;
2408 hdr_size = n_labels * sizeof(struct mpls_shim_hdr);
2411 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2412 if (!skb) {
2413 err = -ENOBUFS;
2414 goto errout;
2417 skb->protocol = htons(ETH_P_MPLS_UC);
2419 if (hdr_size) {
2420 bool bos;
2421 int i;
2423 if (skb_cow(skb, hdr_size)) {
2424 err = -ENOBUFS;
2425 goto errout_free;
2428 skb_reserve(skb, hdr_size);
2429 skb_push(skb, hdr_size);
2430 skb_reset_network_header(skb);
2432 /* Push new labels */
2433 hdr = mpls_hdr(skb);
2434 bos = true;
2435 for (i = n_labels - 1; i >= 0; i--) {
2436 hdr[i] = mpls_entry_encode(labels[i],
2437 1, 0, bos);
2438 bos = false;
2442 nh = mpls_select_multipath(rt, skb);
2443 if (!nh) {
2444 err = -ENETUNREACH;
2445 goto errout_free;
2448 if (hdr_size) {
2449 skb_pull(skb, hdr_size);
2450 skb_reset_network_header(skb);
2453 nlh = nlmsg_put(skb, portid, in_nlh->nlmsg_seq,
2454 RTM_NEWROUTE, sizeof(*r), 0);
2455 if (!nlh) {
2456 err = -EMSGSIZE;
2457 goto errout_free;
2460 r = nlmsg_data(nlh);
2461 r->rtm_family = AF_MPLS;
2462 r->rtm_dst_len = 20;
2463 r->rtm_src_len = 0;
2464 r->rtm_table = RT_TABLE_MAIN;
2465 r->rtm_type = RTN_UNICAST;
2466 r->rtm_scope = RT_SCOPE_UNIVERSE;
2467 r->rtm_protocol = rt->rt_protocol;
2468 r->rtm_flags = 0;
2470 if (nla_put_labels(skb, RTA_DST, 1, &in_label))
2471 goto nla_put_failure;
2473 if (nh->nh_labels &&
2474 nla_put_labels(skb, RTA_NEWDST, nh->nh_labels,
2475 nh->nh_label))
2476 goto nla_put_failure;
2478 if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC &&
2479 nla_put_via(skb, nh->nh_via_table, mpls_nh_via(rt, nh),
2480 nh->nh_via_alen))
2481 goto nla_put_failure;
2482 dev = rtnl_dereference(nh->nh_dev);
2483 if (dev && nla_put_u32(skb, RTA_OIF, dev->ifindex))
2484 goto nla_put_failure;
2486 nlmsg_end(skb, nlh);
2488 err = rtnl_unicast(skb, net, portid);
2489 errout:
2490 return err;
2492 nla_put_failure:
2493 nlmsg_cancel(skb, nlh);
2494 err = -EMSGSIZE;
2495 errout_free:
2496 kfree_skb(skb);
2497 return err;
2500 static int resize_platform_label_table(struct net *net, size_t limit)
2502 size_t size = sizeof(struct mpls_route *) * limit;
2503 size_t old_limit;
2504 size_t cp_size;
2505 struct mpls_route __rcu **labels = NULL, **old;
2506 struct mpls_route *rt0 = NULL, *rt2 = NULL;
2507 unsigned index;
2509 if (size) {
2510 labels = kvzalloc(size, GFP_KERNEL);
2511 if (!labels)
2512 goto nolabels;
2515 /* In case the predefined labels need to be populated */
2516 if (limit > MPLS_LABEL_IPV4NULL) {
2517 struct net_device *lo = net->loopback_dev;
2518 rt0 = mpls_rt_alloc(1, lo->addr_len, 0);
2519 if (IS_ERR(rt0))
2520 goto nort0;
2521 RCU_INIT_POINTER(rt0->rt_nh->nh_dev, lo);
2522 rt0->rt_protocol = RTPROT_KERNEL;
2523 rt0->rt_payload_type = MPT_IPV4;
2524 rt0->rt_ttl_propagate = MPLS_TTL_PROP_DEFAULT;
2525 rt0->rt_nh->nh_via_table = NEIGH_LINK_TABLE;
2526 rt0->rt_nh->nh_via_alen = lo->addr_len;
2527 memcpy(__mpls_nh_via(rt0, rt0->rt_nh), lo->dev_addr,
2528 lo->addr_len);
2530 if (limit > MPLS_LABEL_IPV6NULL) {
2531 struct net_device *lo = net->loopback_dev;
2532 rt2 = mpls_rt_alloc(1, lo->addr_len, 0);
2533 if (IS_ERR(rt2))
2534 goto nort2;
2535 RCU_INIT_POINTER(rt2->rt_nh->nh_dev, lo);
2536 rt2->rt_protocol = RTPROT_KERNEL;
2537 rt2->rt_payload_type = MPT_IPV6;
2538 rt2->rt_ttl_propagate = MPLS_TTL_PROP_DEFAULT;
2539 rt2->rt_nh->nh_via_table = NEIGH_LINK_TABLE;
2540 rt2->rt_nh->nh_via_alen = lo->addr_len;
2541 memcpy(__mpls_nh_via(rt2, rt2->rt_nh), lo->dev_addr,
2542 lo->addr_len);
2545 rtnl_lock();
2546 /* Remember the original table */
2547 old = rtnl_dereference(net->mpls.platform_label);
2548 old_limit = net->mpls.platform_labels;
2550 /* Free any labels beyond the new table */
2551 for (index = limit; index < old_limit; index++)
2552 mpls_route_update(net, index, NULL, NULL);
2554 /* Copy over the old labels */
2555 cp_size = size;
2556 if (old_limit < limit)
2557 cp_size = old_limit * sizeof(struct mpls_route *);
2559 memcpy(labels, old, cp_size);
2561 /* If needed set the predefined labels */
2562 if ((old_limit <= MPLS_LABEL_IPV6NULL) &&
2563 (limit > MPLS_LABEL_IPV6NULL)) {
2564 RCU_INIT_POINTER(labels[MPLS_LABEL_IPV6NULL], rt2);
2565 rt2 = NULL;
2568 if ((old_limit <= MPLS_LABEL_IPV4NULL) &&
2569 (limit > MPLS_LABEL_IPV4NULL)) {
2570 RCU_INIT_POINTER(labels[MPLS_LABEL_IPV4NULL], rt0);
2571 rt0 = NULL;
2574 /* Update the global pointers */
2575 net->mpls.platform_labels = limit;
2576 rcu_assign_pointer(net->mpls.platform_label, labels);
2578 rtnl_unlock();
2580 mpls_rt_free(rt2);
2581 mpls_rt_free(rt0);
2583 if (old) {
2584 synchronize_rcu();
2585 kvfree(old);
2587 return 0;
2589 nort2:
2590 mpls_rt_free(rt0);
2591 nort0:
2592 kvfree(labels);
2593 nolabels:
2594 return -ENOMEM;
2597 static int mpls_platform_labels(struct ctl_table *table, int write,
2598 void __user *buffer, size_t *lenp, loff_t *ppos)
2600 struct net *net = table->data;
2601 int platform_labels = net->mpls.platform_labels;
2602 int ret;
2603 struct ctl_table tmp = {
2604 .procname = table->procname,
2605 .data = &platform_labels,
2606 .maxlen = sizeof(int),
2607 .mode = table->mode,
2608 .extra1 = SYSCTL_ZERO,
2609 .extra2 = &label_limit,
2612 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
2614 if (write && ret == 0)
2615 ret = resize_platform_label_table(net, platform_labels);
2617 return ret;
2620 #define MPLS_NS_SYSCTL_OFFSET(field) \
2621 (&((struct net *)0)->field)
2623 static const struct ctl_table mpls_table[] = {
2625 .procname = "platform_labels",
2626 .data = NULL,
2627 .maxlen = sizeof(int),
2628 .mode = 0644,
2629 .proc_handler = mpls_platform_labels,
2632 .procname = "ip_ttl_propagate",
2633 .data = MPLS_NS_SYSCTL_OFFSET(mpls.ip_ttl_propagate),
2634 .maxlen = sizeof(int),
2635 .mode = 0644,
2636 .proc_handler = proc_dointvec_minmax,
2637 .extra1 = SYSCTL_ZERO,
2638 .extra2 = SYSCTL_ONE,
2641 .procname = "default_ttl",
2642 .data = MPLS_NS_SYSCTL_OFFSET(mpls.default_ttl),
2643 .maxlen = sizeof(int),
2644 .mode = 0644,
2645 .proc_handler = proc_dointvec_minmax,
2646 .extra1 = SYSCTL_ONE,
2647 .extra2 = &ttl_max,
2652 static int mpls_net_init(struct net *net)
2654 struct ctl_table *table;
2655 int i;
2657 net->mpls.platform_labels = 0;
2658 net->mpls.platform_label = NULL;
2659 net->mpls.ip_ttl_propagate = 1;
2660 net->mpls.default_ttl = 255;
2662 table = kmemdup(mpls_table, sizeof(mpls_table), GFP_KERNEL);
2663 if (table == NULL)
2664 return -ENOMEM;
2666 /* Table data contains only offsets relative to the base of
2667 * the mdev at this point, so make them absolute.
2669 for (i = 0; i < ARRAY_SIZE(mpls_table) - 1; i++)
2670 table[i].data = (char *)net + (uintptr_t)table[i].data;
2672 net->mpls.ctl = register_net_sysctl(net, "net/mpls", table);
2673 if (net->mpls.ctl == NULL) {
2674 kfree(table);
2675 return -ENOMEM;
2678 return 0;
2681 static void mpls_net_exit(struct net *net)
2683 struct mpls_route __rcu **platform_label;
2684 size_t platform_labels;
2685 struct ctl_table *table;
2686 unsigned int index;
2688 table = net->mpls.ctl->ctl_table_arg;
2689 unregister_net_sysctl_table(net->mpls.ctl);
2690 kfree(table);
2692 /* An rcu grace period has passed since there was a device in
2693 * the network namespace (and thus the last in flight packet)
2694 * left this network namespace. This is because
2695 * unregister_netdevice_many and netdev_run_todo has completed
2696 * for each network device that was in this network namespace.
2698 * As such no additional rcu synchronization is necessary when
2699 * freeing the platform_label table.
2701 rtnl_lock();
2702 platform_label = rtnl_dereference(net->mpls.platform_label);
2703 platform_labels = net->mpls.platform_labels;
2704 for (index = 0; index < platform_labels; index++) {
2705 struct mpls_route *rt = rtnl_dereference(platform_label[index]);
2706 RCU_INIT_POINTER(platform_label[index], NULL);
2707 mpls_notify_route(net, index, rt, NULL, NULL);
2708 mpls_rt_free(rt);
2710 rtnl_unlock();
2712 kvfree(platform_label);
2715 static struct pernet_operations mpls_net_ops = {
2716 .init = mpls_net_init,
2717 .exit = mpls_net_exit,
2720 static struct rtnl_af_ops mpls_af_ops __read_mostly = {
2721 .family = AF_MPLS,
2722 .fill_stats_af = mpls_fill_stats_af,
2723 .get_stats_af_size = mpls_get_stats_af_size,
2726 static int __init mpls_init(void)
2728 int err;
2730 BUILD_BUG_ON(sizeof(struct mpls_shim_hdr) != 4);
2732 err = register_pernet_subsys(&mpls_net_ops);
2733 if (err)
2734 goto out;
2736 err = register_netdevice_notifier(&mpls_dev_notifier);
2737 if (err)
2738 goto out_unregister_pernet;
2740 dev_add_pack(&mpls_packet_type);
2742 rtnl_af_register(&mpls_af_ops);
2744 rtnl_register_module(THIS_MODULE, PF_MPLS, RTM_NEWROUTE,
2745 mpls_rtm_newroute, NULL, 0);
2746 rtnl_register_module(THIS_MODULE, PF_MPLS, RTM_DELROUTE,
2747 mpls_rtm_delroute, NULL, 0);
2748 rtnl_register_module(THIS_MODULE, PF_MPLS, RTM_GETROUTE,
2749 mpls_getroute, mpls_dump_routes, 0);
2750 rtnl_register_module(THIS_MODULE, PF_MPLS, RTM_GETNETCONF,
2751 mpls_netconf_get_devconf,
2752 mpls_netconf_dump_devconf, 0);
2753 err = ipgre_tunnel_encap_add_mpls_ops();
2754 if (err)
2755 pr_err("Can't add mpls over gre tunnel ops\n");
2757 err = 0;
2758 out:
2759 return err;
2761 out_unregister_pernet:
2762 unregister_pernet_subsys(&mpls_net_ops);
2763 goto out;
2765 module_init(mpls_init);
2767 static void __exit mpls_exit(void)
2769 rtnl_unregister_all(PF_MPLS);
2770 rtnl_af_unregister(&mpls_af_ops);
2771 dev_remove_pack(&mpls_packet_type);
2772 unregister_netdevice_notifier(&mpls_dev_notifier);
2773 unregister_pernet_subsys(&mpls_net_ops);
2774 ipgre_tunnel_encap_del_mpls_ops();
2776 module_exit(mpls_exit);
2778 MODULE_DESCRIPTION("MultiProtocol Label Switching");
2779 MODULE_LICENSE("GPL v2");
2780 MODULE_ALIAS_NETPROTO(PF_MPLS);