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Merge tag 'secureexec-v4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git...
[linux/fpc-iii.git] / net / mpls / af_mpls.c
blobc5b9ce41d66fadc903c9341c7808ec3d3ce89933
1 #include <linux/types.h>
2 #include <linux/skbuff.h>
3 #include <linux/socket.h>
4 #include <linux/sysctl.h>
5 #include <linux/net.h>
6 #include <linux/module.h>
7 #include <linux/if_arp.h>
8 #include <linux/ipv6.h>
9 #include <linux/mpls.h>
10 #include <linux/netconf.h>
11 #include <linux/vmalloc.h>
12 #include <linux/percpu.h>
13 #include <net/ip.h>
14 #include <net/dst.h>
15 #include <net/sock.h>
16 #include <net/arp.h>
17 #include <net/ip_fib.h>
18 #include <net/netevent.h>
19 #include <net/netns/generic.h>
20 #if IS_ENABLED(CONFIG_IPV6)
21 #include <net/ipv6.h>
22 #endif
23 #include <net/addrconf.h>
24 #include <net/nexthop.h>
25 #include "internal.h"
26
27 /* max memory we will use for mpls_route */
28 #define MAX_MPLS_ROUTE_MEM 4096
29
30 /* Maximum number of labels to look ahead at when selecting a path of
31 * a multipath route
32 */
33 #define MAX_MP_SELECT_LABELS 4
34
35 #define MPLS_NEIGH_TABLE_UNSPEC (NEIGH_LINK_TABLE + 1)
36
37 static int zero = 0;
38 static int one = 1;
39 static int label_limit = (1 << 20) - 1;
40 static int ttl_max = 255;
41
42 static void rtmsg_lfib(int event, u32 label, struct mpls_route *rt,
43 struct nlmsghdr *nlh, struct net *net, u32 portid,
44 unsigned int nlm_flags);
45
46 static struct mpls_route *mpls_route_input_rcu(struct net *net, unsigned index)
47 {
48 struct mpls_route *rt = NULL;
49
50 if (index < net->mpls.platform_labels) {
51 struct mpls_route __rcu **platform_label =
52 rcu_dereference(net->mpls.platform_label);
53 rt = rcu_dereference(platform_label[index]);
54 }
55 return rt;
56 }
57
58 bool mpls_output_possible(const struct net_device *dev)
59 {
60 return dev && (dev->flags & IFF_UP) && netif_carrier_ok(dev);
61 }
62 EXPORT_SYMBOL_GPL(mpls_output_possible);
63
64 static u8 *__mpls_nh_via(struct mpls_route *rt, struct mpls_nh *nh)
65 {
66 return (u8 *)nh + rt->rt_via_offset;
67 }
68
69 static const u8 *mpls_nh_via(const struct mpls_route *rt,
70 const struct mpls_nh *nh)
71 {
72 return __mpls_nh_via((struct mpls_route *)rt, (struct mpls_nh *)nh);
73 }
74
75 static unsigned int mpls_nh_header_size(const struct mpls_nh *nh)
76 {
77 /* The size of the layer 2.5 labels to be added for this route */
78 return nh->nh_labels * sizeof(struct mpls_shim_hdr);
79 }
80
81 unsigned int mpls_dev_mtu(const struct net_device *dev)
82 {
83 /* The amount of data the layer 2 frame can hold */
84 return dev->mtu;
85 }
86 EXPORT_SYMBOL_GPL(mpls_dev_mtu);
87
88 bool mpls_pkt_too_big(const struct sk_buff *skb, unsigned int mtu)
89 {
90 if (skb->len <= mtu)
91 return false;
92
93 if (skb_is_gso(skb) && skb_gso_validate_mtu(skb, mtu))
94 return false;
95
96 return true;
97 }
98 EXPORT_SYMBOL_GPL(mpls_pkt_too_big);
99
100 void mpls_stats_inc_outucastpkts(struct net_device *dev,
101 const struct sk_buff *skb)
102 {
103 struct mpls_dev *mdev;
104
105 if (skb->protocol == htons(ETH_P_MPLS_UC)) {
106 mdev = mpls_dev_get(dev);
107 if (mdev)
108 MPLS_INC_STATS_LEN(mdev, skb->len,
109 tx_packets,
110 tx_bytes);
111 } else if (skb->protocol == htons(ETH_P_IP)) {
112 IP_UPD_PO_STATS(dev_net(dev), IPSTATS_MIB_OUT, skb->len);
113 #if IS_ENABLED(CONFIG_IPV6)
114 } else if (skb->protocol == htons(ETH_P_IPV6)) {
115 struct inet6_dev *in6dev = __in6_dev_get(dev);
116
117 if (in6dev)
118 IP6_UPD_PO_STATS(dev_net(dev), in6dev,
119 IPSTATS_MIB_OUT, skb->len);
120 #endif
121 }
122 }
123 EXPORT_SYMBOL_GPL(mpls_stats_inc_outucastpkts);
124
125 static u32 mpls_multipath_hash(struct mpls_route *rt, struct sk_buff *skb)
126 {
127 struct mpls_entry_decoded dec;
128 unsigned int mpls_hdr_len = 0;
129 struct mpls_shim_hdr *hdr;
130 bool eli_seen = false;
131 int label_index;
132 u32 hash = 0;
133
134 for (label_index = 0; label_index < MAX_MP_SELECT_LABELS;
135 label_index++) {
136 mpls_hdr_len += sizeof(*hdr);
137 if (!pskb_may_pull(skb, mpls_hdr_len))
138 break;
139
140 /* Read and decode the current label */
141 hdr = mpls_hdr(skb) + label_index;
142 dec = mpls_entry_decode(hdr);
143
144 /* RFC6790 - reserved labels MUST NOT be used as keys
145 * for the load-balancing function
146 */
147 if (likely(dec.label >= MPLS_LABEL_FIRST_UNRESERVED)) {
148 hash = jhash_1word(dec.label, hash);
149
150 /* The entropy label follows the entropy label
151 * indicator, so this means that the entropy
152 * label was just added to the hash - no need to
153 * go any deeper either in the label stack or in the
154 * payload
155 */
156 if (eli_seen)
157 break;
158 } else if (dec.label == MPLS_LABEL_ENTROPY) {
159 eli_seen = true;
160 }
161
162 if (!dec.bos)
163 continue;
164
165 /* found bottom label; does skb have room for a header? */
166 if (pskb_may_pull(skb, mpls_hdr_len + sizeof(struct iphdr))) {
167 const struct iphdr *v4hdr;
168
169 v4hdr = (const struct iphdr *)(hdr + 1);
170 if (v4hdr->version == 4) {
171 hash = jhash_3words(ntohl(v4hdr->saddr),
172 ntohl(v4hdr->daddr),
173 v4hdr->protocol, hash);
174 } else if (v4hdr->version == 6 &&
175 pskb_may_pull(skb, mpls_hdr_len +
176 sizeof(struct ipv6hdr))) {
177 const struct ipv6hdr *v6hdr;
178
179 v6hdr = (const struct ipv6hdr *)(hdr + 1);
180 hash = __ipv6_addr_jhash(&v6hdr->saddr, hash);
181 hash = __ipv6_addr_jhash(&v6hdr->daddr, hash);
182 hash = jhash_1word(v6hdr->nexthdr, hash);
183 }
184 }
185
186 break;
187 }
188
189 return hash;
190 }
191
192 static struct mpls_nh *mpls_get_nexthop(struct mpls_route *rt, u8 index)
193 {
194 return (struct mpls_nh *)((u8 *)rt->rt_nh + index * rt->rt_nh_size);
195 }
196
197 /* number of alive nexthops (rt->rt_nhn_alive) and the flags for
198 * a next hop (nh->nh_flags) are modified by netdev event handlers.
199 * Since those fields can change at any moment, use READ_ONCE to
200 * access both.
201 */
202 static struct mpls_nh *mpls_select_multipath(struct mpls_route *rt,
203 struct sk_buff *skb)
204 {
205 u32 hash = 0;
206 int nh_index = 0;
207 int n = 0;
208 u8 alive;
209
210 /* No need to look further into packet if there's only
211 * one path
212 */
213 if (rt->rt_nhn == 1)
214 return rt->rt_nh;
215
216 alive = READ_ONCE(rt->rt_nhn_alive);
217 if (alive == 0)
218 return NULL;
219
220 hash = mpls_multipath_hash(rt, skb);
221 nh_index = hash % alive;
222 if (alive == rt->rt_nhn)
223 goto out;
224 for_nexthops(rt) {
225 unsigned int nh_flags = READ_ONCE(nh->nh_flags);
226
227 if (nh_flags & (RTNH_F_DEAD | RTNH_F_LINKDOWN))
228 continue;
229 if (n == nh_index)
230 return nh;
231 n++;
232 } endfor_nexthops(rt);
233
234 out:
235 return mpls_get_nexthop(rt, nh_index);
236 }
237
238 static bool mpls_egress(struct net *net, struct mpls_route *rt,
239 struct sk_buff *skb, struct mpls_entry_decoded dec)
240 {
241 enum mpls_payload_type payload_type;
242 bool success = false;
243
244 /* The IPv4 code below accesses through the IPv4 header
245 * checksum, which is 12 bytes into the packet.
246 * The IPv6 code below accesses through the IPv6 hop limit
247 * which is 8 bytes into the packet.
248 *
249 * For all supported cases there should always be at least 12
250 * bytes of packet data present. The IPv4 header is 20 bytes
251 * without options and the IPv6 header is always 40 bytes
252 * long.
253 */
254 if (!pskb_may_pull(skb, 12))
255 return false;
256
257 payload_type = rt->rt_payload_type;
258 if (payload_type == MPT_UNSPEC)
259 payload_type = ip_hdr(skb)->version;
260
261 switch (payload_type) {
262 case MPT_IPV4: {
263 struct iphdr *hdr4 = ip_hdr(skb);
264 u8 new_ttl;
265 skb->protocol = htons(ETH_P_IP);
266
267 /* If propagating TTL, take the decremented TTL from
268 * the incoming MPLS header, otherwise decrement the
269 * TTL, but only if not 0 to avoid underflow.
270 */
271 if (rt->rt_ttl_propagate == MPLS_TTL_PROP_ENABLED ||
272 (rt->rt_ttl_propagate == MPLS_TTL_PROP_DEFAULT &&
273 net->mpls.ip_ttl_propagate))
274 new_ttl = dec.ttl;
275 else
276 new_ttl = hdr4->ttl ? hdr4->ttl - 1 : 0;
277
278 csum_replace2(&hdr4->check,
279 htons(hdr4->ttl << 8),
280 htons(new_ttl << 8));
281 hdr4->ttl = new_ttl;
282 success = true;
283 break;
284 }
285 case MPT_IPV6: {
286 struct ipv6hdr *hdr6 = ipv6_hdr(skb);
287 skb->protocol = htons(ETH_P_IPV6);
288
289 /* If propagating TTL, take the decremented TTL from
290 * the incoming MPLS header, otherwise decrement the
291 * hop limit, but only if not 0 to avoid underflow.
292 */
293 if (rt->rt_ttl_propagate == MPLS_TTL_PROP_ENABLED ||
294 (rt->rt_ttl_propagate == MPLS_TTL_PROP_DEFAULT &&
295 net->mpls.ip_ttl_propagate))
296 hdr6->hop_limit = dec.ttl;
297 else if (hdr6->hop_limit)
298 hdr6->hop_limit = hdr6->hop_limit - 1;
299 success = true;
300 break;
301 }
302 case MPT_UNSPEC:
303 /* Should have decided which protocol it is by now */
304 break;
305 }
306
307 return success;
308 }
309
310 static int mpls_forward(struct sk_buff *skb, struct net_device *dev,
311 struct packet_type *pt, struct net_device *orig_dev)
312 {
313 struct net *net = dev_net(dev);
314 struct mpls_shim_hdr *hdr;
315 struct mpls_route *rt;
316 struct mpls_nh *nh;
317 struct mpls_entry_decoded dec;
318 struct net_device *out_dev;
319 struct mpls_dev *out_mdev;
320 struct mpls_dev *mdev;
321 unsigned int hh_len;
322 unsigned int new_header_size;
323 unsigned int mtu;
324 int err;
325
326 /* Careful this entire function runs inside of an rcu critical section */
327
328 mdev = mpls_dev_get(dev);
329 if (!mdev)
330 goto drop;
331
332 MPLS_INC_STATS_LEN(mdev, skb->len, rx_packets,
333 rx_bytes);
334
335 if (!mdev->input_enabled) {
336 MPLS_INC_STATS(mdev, rx_dropped);
337 goto drop;
338 }
339
340 if (skb->pkt_type != PACKET_HOST)
341 goto err;
342
343 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
344 goto err;
345
346 if (!pskb_may_pull(skb, sizeof(*hdr)))
347 goto err;
348
349 /* Read and decode the label */
350 hdr = mpls_hdr(skb);
351 dec = mpls_entry_decode(hdr);
352
353 rt = mpls_route_input_rcu(net, dec.label);
354 if (!rt) {
355 MPLS_INC_STATS(mdev, rx_noroute);
356 goto drop;
357 }
358
359 nh = mpls_select_multipath(rt, skb);
360 if (!nh)
361 goto err;
362
363 /* Pop the label */
364 skb_pull(skb, sizeof(*hdr));
365 skb_reset_network_header(skb);
366
367 skb_orphan(skb);
368
369 if (skb_warn_if_lro(skb))
370 goto err;
371
372 skb_forward_csum(skb);
373
374 /* Verify ttl is valid */
375 if (dec.ttl <= 1)
376 goto err;
377 dec.ttl -= 1;
378
379 /* Find the output device */
380 out_dev = rcu_dereference(nh->nh_dev);
381 if (!mpls_output_possible(out_dev))
382 goto tx_err;
383
384 /* Verify the destination can hold the packet */
385 new_header_size = mpls_nh_header_size(nh);
386 mtu = mpls_dev_mtu(out_dev);
387 if (mpls_pkt_too_big(skb, mtu - new_header_size))
388 goto tx_err;
389
390 hh_len = LL_RESERVED_SPACE(out_dev);
391 if (!out_dev->header_ops)
392 hh_len = 0;
393
394 /* Ensure there is enough space for the headers in the skb */
395 if (skb_cow(skb, hh_len + new_header_size))
396 goto tx_err;
397
398 skb->dev = out_dev;
399 skb->protocol = htons(ETH_P_MPLS_UC);
400
401 if (unlikely(!new_header_size && dec.bos)) {
402 /* Penultimate hop popping */
403 if (!mpls_egress(dev_net(out_dev), rt, skb, dec))
404 goto err;
405 } else {
406 bool bos;
407 int i;
408 skb_push(skb, new_header_size);
409 skb_reset_network_header(skb);
410 /* Push the new labels */
411 hdr = mpls_hdr(skb);
412 bos = dec.bos;
413 for (i = nh->nh_labels - 1; i >= 0; i--) {
414 hdr[i] = mpls_entry_encode(nh->nh_label[i],
415 dec.ttl, 0, bos);
416 bos = false;
417 }
418 }
419
420 mpls_stats_inc_outucastpkts(out_dev, skb);
421
422 /* If via wasn't specified then send out using device address */
423 if (nh->nh_via_table == MPLS_NEIGH_TABLE_UNSPEC)
424 err = neigh_xmit(NEIGH_LINK_TABLE, out_dev,
425 out_dev->dev_addr, skb);
426 else
427 err = neigh_xmit(nh->nh_via_table, out_dev,
428 mpls_nh_via(rt, nh), skb);
429 if (err)
430 net_dbg_ratelimited("%s: packet transmission failed: %d\n",
431 __func__, err);
432 return 0;
433
434 tx_err:
435 out_mdev = out_dev ? mpls_dev_get(out_dev) : NULL;
436 if (out_mdev)
437 MPLS_INC_STATS(out_mdev, tx_errors);
438 goto drop;
439 err:
440 MPLS_INC_STATS(mdev, rx_errors);
441 drop:
442 kfree_skb(skb);
443 return NET_RX_DROP;
444 }
445
446 static struct packet_type mpls_packet_type __read_mostly = {
447 .type = cpu_to_be16(ETH_P_MPLS_UC),
448 .func = mpls_forward,
449 };
450
451 static const struct nla_policy rtm_mpls_policy[RTA_MAX+1] = {
452 [RTA_DST] = { .type = NLA_U32 },
453 [RTA_OIF] = { .type = NLA_U32 },
454 [RTA_TTL_PROPAGATE] = { .type = NLA_U8 },
455 };
456
457 struct mpls_route_config {
458 u32 rc_protocol;
459 u32 rc_ifindex;
460 u8 rc_via_table;
461 u8 rc_via_alen;
462 u8 rc_via[MAX_VIA_ALEN];
463 u32 rc_label;
464 u8 rc_ttl_propagate;
465 u8 rc_output_labels;
466 u32 rc_output_label[MAX_NEW_LABELS];
467 u32 rc_nlflags;
468 enum mpls_payload_type rc_payload_type;
469 struct nl_info rc_nlinfo;
470 struct rtnexthop *rc_mp;
471 int rc_mp_len;
472 };
473
474 /* all nexthops within a route have the same size based on max
475 * number of labels and max via length for a hop
476 */
477 static struct mpls_route *mpls_rt_alloc(u8 num_nh, u8 max_alen, u8 max_labels)
478 {
479 u8 nh_size = MPLS_NH_SIZE(max_labels, max_alen);
480 struct mpls_route *rt;
481 size_t size;
482
483 size = sizeof(*rt) + num_nh * nh_size;
484 if (size > MAX_MPLS_ROUTE_MEM)
485 return ERR_PTR(-EINVAL);
486
487 rt = kzalloc(size, GFP_KERNEL);
488 if (!rt)
489 return ERR_PTR(-ENOMEM);
490
491 rt->rt_nhn = num_nh;
492 rt->rt_nhn_alive = num_nh;
493 rt->rt_nh_size = nh_size;
494 rt->rt_via_offset = MPLS_NH_VIA_OFF(max_labels);
495
496 return rt;
497 }
498
499 static void mpls_rt_free(struct mpls_route *rt)
500 {
501 if (rt)
502 kfree_rcu(rt, rt_rcu);
503 }
504
505 static void mpls_notify_route(struct net *net, unsigned index,
506 struct mpls_route *old, struct mpls_route *new,
507 const struct nl_info *info)
508 {
509 struct nlmsghdr *nlh = info ? info->nlh : NULL;
510 unsigned portid = info ? info->portid : 0;
511 int event = new ? RTM_NEWROUTE : RTM_DELROUTE;
512 struct mpls_route *rt = new ? new : old;
513 unsigned nlm_flags = (old && new) ? NLM_F_REPLACE : 0;
514 /* Ignore reserved labels for now */
515 if (rt && (index >= MPLS_LABEL_FIRST_UNRESERVED))
516 rtmsg_lfib(event, index, rt, nlh, net, portid, nlm_flags);
517 }
518
519 static void mpls_route_update(struct net *net, unsigned index,
520 struct mpls_route *new,
521 const struct nl_info *info)
522 {
523 struct mpls_route __rcu **platform_label;
524 struct mpls_route *rt;
525
526 ASSERT_RTNL();
527
528 platform_label = rtnl_dereference(net->mpls.platform_label);
529 rt = rtnl_dereference(platform_label[index]);
530 rcu_assign_pointer(platform_label[index], new);
531
532 mpls_notify_route(net, index, rt, new, info);
533
534 /* If we removed a route free it now */
535 mpls_rt_free(rt);
536 }
537
538 static unsigned find_free_label(struct net *net)
539 {
540 struct mpls_route __rcu **platform_label;
541 size_t platform_labels;
542 unsigned index;
543
544 platform_label = rtnl_dereference(net->mpls.platform_label);
545 platform_labels = net->mpls.platform_labels;
546 for (index = MPLS_LABEL_FIRST_UNRESERVED; index < platform_labels;
547 index++) {
548 if (!rtnl_dereference(platform_label[index]))
549 return index;
550 }
551 return LABEL_NOT_SPECIFIED;
552 }
553
554 #if IS_ENABLED(CONFIG_INET)
555 static struct net_device *inet_fib_lookup_dev(struct net *net,
556 const void *addr)
557 {
558 struct net_device *dev;
559 struct rtable *rt;
560 struct in_addr daddr;
561
562 memcpy(&daddr, addr, sizeof(struct in_addr));
563 rt = ip_route_output(net, daddr.s_addr, 0, 0, 0);
564 if (IS_ERR(rt))
565 return ERR_CAST(rt);
566
567 dev = rt->dst.dev;
568 dev_hold(dev);
569
570 ip_rt_put(rt);
571
572 return dev;
573 }
574 #else
575 static struct net_device *inet_fib_lookup_dev(struct net *net,
576 const void *addr)
577 {
578 return ERR_PTR(-EAFNOSUPPORT);
579 }
580 #endif
581
582 #if IS_ENABLED(CONFIG_IPV6)
583 static struct net_device *inet6_fib_lookup_dev(struct net *net,
584 const void *addr)
585 {
586 struct net_device *dev;
587 struct dst_entry *dst;
588 struct flowi6 fl6;
589 int err;
590
591 if (!ipv6_stub)
592 return ERR_PTR(-EAFNOSUPPORT);
593
594 memset(&fl6, 0, sizeof(fl6));
595 memcpy(&fl6.daddr, addr, sizeof(struct in6_addr));
596 err = ipv6_stub->ipv6_dst_lookup(net, NULL, &dst, &fl6);
597 if (err)
598 return ERR_PTR(err);
599
600 dev = dst->dev;
601 dev_hold(dev);
602 dst_release(dst);
603
604 return dev;
605 }
606 #else
607 static struct net_device *inet6_fib_lookup_dev(struct net *net,
608 const void *addr)
609 {
610 return ERR_PTR(-EAFNOSUPPORT);
611 }
612 #endif
613
614 static struct net_device *find_outdev(struct net *net,
615 struct mpls_route *rt,
616 struct mpls_nh *nh, int oif)
617 {
618 struct net_device *dev = NULL;
619
620 if (!oif) {
621 switch (nh->nh_via_table) {
622 case NEIGH_ARP_TABLE:
623 dev = inet_fib_lookup_dev(net, mpls_nh_via(rt, nh));
624 break;
625 case NEIGH_ND_TABLE:
626 dev = inet6_fib_lookup_dev(net, mpls_nh_via(rt, nh));
627 break;
628 case NEIGH_LINK_TABLE:
629 break;
630 }
631 } else {
632 dev = dev_get_by_index(net, oif);
633 }
634
635 if (!dev)
636 return ERR_PTR(-ENODEV);
637
638 if (IS_ERR(dev))
639 return dev;
640
641 /* The caller is holding rtnl anyways, so release the dev reference */
642 dev_put(dev);
643
644 return dev;
645 }
646
647 static int mpls_nh_assign_dev(struct net *net, struct mpls_route *rt,
648 struct mpls_nh *nh, int oif)
649 {
650 struct net_device *dev = NULL;
651 int err = -ENODEV;
652
653 dev = find_outdev(net, rt, nh, oif);
654 if (IS_ERR(dev)) {
655 err = PTR_ERR(dev);
656 dev = NULL;
657 goto errout;
658 }
659
660 /* Ensure this is a supported device */
661 err = -EINVAL;
662 if (!mpls_dev_get(dev))
663 goto errout;
664
665 if ((nh->nh_via_table == NEIGH_LINK_TABLE) &&
666 (dev->addr_len != nh->nh_via_alen))
667 goto errout;
668
669 RCU_INIT_POINTER(nh->nh_dev, dev);
670
671 if (!(dev->flags & IFF_UP)) {
672 nh->nh_flags |= RTNH_F_DEAD;
673 } else {
674 unsigned int flags;
675
676 flags = dev_get_flags(dev);
677 if (!(flags & (IFF_RUNNING | IFF_LOWER_UP)))
678 nh->nh_flags |= RTNH_F_LINKDOWN;
679 }
680
681 return 0;
682
683 errout:
684 return err;
685 }
686
687 static int nla_get_via(const struct nlattr *nla, u8 *via_alen, u8 *via_table,
688 u8 via_addr[], struct netlink_ext_ack *extack)
689 {
690 struct rtvia *via = nla_data(nla);
691 int err = -EINVAL;
692 int alen;
693
694 if (nla_len(nla) < offsetof(struct rtvia, rtvia_addr)) {
695 NL_SET_ERR_MSG_ATTR(extack, nla,
696 "Invalid attribute length for RTA_VIA");
697 goto errout;
698 }
699 alen = nla_len(nla) -
700 offsetof(struct rtvia, rtvia_addr);
701 if (alen > MAX_VIA_ALEN) {
702 NL_SET_ERR_MSG_ATTR(extack, nla,
703 "Invalid address length for RTA_VIA");
704 goto errout;
705 }
706
707 /* Validate the address family */
708 switch (via->rtvia_family) {
709 case AF_PACKET:
710 *via_table = NEIGH_LINK_TABLE;
711 break;
712 case AF_INET:
713 *via_table = NEIGH_ARP_TABLE;
714 if (alen != 4)
715 goto errout;
716 break;
717 case AF_INET6:
718 *via_table = NEIGH_ND_TABLE;
719 if (alen != 16)
720 goto errout;
721 break;
722 default:
723 /* Unsupported address family */
724 goto errout;
725 }
726
727 memcpy(via_addr, via->rtvia_addr, alen);
728 *via_alen = alen;
729 err = 0;
730
731 errout:
732 return err;
733 }
734
735 static int mpls_nh_build_from_cfg(struct mpls_route_config *cfg,
736 struct mpls_route *rt)
737 {
738 struct net *net = cfg->rc_nlinfo.nl_net;
739 struct mpls_nh *nh = rt->rt_nh;
740 int err;
741 int i;
742
743 if (!nh)
744 return -ENOMEM;
745
746 nh->nh_labels = cfg->rc_output_labels;
747 for (i = 0; i < nh->nh_labels; i++)
748 nh->nh_label[i] = cfg->rc_output_label[i];
749
750 nh->nh_via_table = cfg->rc_via_table;
751 memcpy(__mpls_nh_via(rt, nh), cfg->rc_via, cfg->rc_via_alen);
752 nh->nh_via_alen = cfg->rc_via_alen;
753
754 err = mpls_nh_assign_dev(net, rt, nh, cfg->rc_ifindex);
755 if (err)
756 goto errout;
757
758 if (nh->nh_flags & (RTNH_F_DEAD | RTNH_F_LINKDOWN))
759 rt->rt_nhn_alive--;
760
761 return 0;
762
763 errout:
764 return err;
765 }
766
767 static int mpls_nh_build(struct net *net, struct mpls_route *rt,
768 struct mpls_nh *nh, int oif, struct nlattr *via,
769 struct nlattr *newdst, u8 max_labels,
770 struct netlink_ext_ack *extack)
771 {
772 int err = -ENOMEM;
773
774 if (!nh)
775 goto errout;
776
777 if (newdst) {
778 err = nla_get_labels(newdst, max_labels, &nh->nh_labels,
779 nh->nh_label, extack);
780 if (err)
781 goto errout;
782 }
783
784 if (via) {
785 err = nla_get_via(via, &nh->nh_via_alen, &nh->nh_via_table,
786 __mpls_nh_via(rt, nh), extack);
787 if (err)
788 goto errout;
789 } else {
790 nh->nh_via_table = MPLS_NEIGH_TABLE_UNSPEC;
791 }
792
793 err = mpls_nh_assign_dev(net, rt, nh, oif);
794 if (err)
795 goto errout;
796
797 return 0;
798
799 errout:
800 return err;
801 }
802
803 static u8 mpls_count_nexthops(struct rtnexthop *rtnh, int len,
804 u8 cfg_via_alen, u8 *max_via_alen,
805 u8 *max_labels)
806 {
807 int remaining = len;
808 u8 nhs = 0;
809
810 *max_via_alen = 0;
811 *max_labels = 0;
812
813 while (rtnh_ok(rtnh, remaining)) {
814 struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
815 int attrlen;
816 u8 n_labels = 0;
817
818 attrlen = rtnh_attrlen(rtnh);
819 nla = nla_find(attrs, attrlen, RTA_VIA);
820 if (nla && nla_len(nla) >=
821 offsetof(struct rtvia, rtvia_addr)) {
822 int via_alen = nla_len(nla) -
823 offsetof(struct rtvia, rtvia_addr);
824
825 if (via_alen <= MAX_VIA_ALEN)
826 *max_via_alen = max_t(u16, *max_via_alen,
827 via_alen);
828 }
829
830 nla = nla_find(attrs, attrlen, RTA_NEWDST);
831 if (nla &&
832 nla_get_labels(nla, MAX_NEW_LABELS, &n_labels,
833 NULL, NULL) != 0)
834 return 0;
835
836 *max_labels = max_t(u8, *max_labels, n_labels);
837
838 /* number of nexthops is tracked by a u8.
839 * Check for overflow.
840 */
841 if (nhs == 255)
842 return 0;
843 nhs++;
844
845 rtnh = rtnh_next(rtnh, &remaining);
846 }
847
848 /* leftover implies invalid nexthop configuration, discard it */
849 return remaining > 0 ? 0 : nhs;
850 }
851
852 static int mpls_nh_build_multi(struct mpls_route_config *cfg,
853 struct mpls_route *rt, u8 max_labels,
854 struct netlink_ext_ack *extack)
855 {
856 struct rtnexthop *rtnh = cfg->rc_mp;
857 struct nlattr *nla_via, *nla_newdst;
858 int remaining = cfg->rc_mp_len;
859 int err = 0;
860 u8 nhs = 0;
861
862 change_nexthops(rt) {
863 int attrlen;
864
865 nla_via = NULL;
866 nla_newdst = NULL;
867
868 err = -EINVAL;
869 if (!rtnh_ok(rtnh, remaining))
870 goto errout;
871
872 /* neither weighted multipath nor any flags
873 * are supported
874 */
875 if (rtnh->rtnh_hops || rtnh->rtnh_flags)
876 goto errout;
877
878 attrlen = rtnh_attrlen(rtnh);
879 if (attrlen > 0) {
880 struct nlattr *attrs = rtnh_attrs(rtnh);
881
882 nla_via = nla_find(attrs, attrlen, RTA_VIA);
883 nla_newdst = nla_find(attrs, attrlen, RTA_NEWDST);
884 }
885
886 err = mpls_nh_build(cfg->rc_nlinfo.nl_net, rt, nh,
887 rtnh->rtnh_ifindex, nla_via, nla_newdst,
888 max_labels, extack);
889 if (err)
890 goto errout;
891
892 if (nh->nh_flags & (RTNH_F_DEAD | RTNH_F_LINKDOWN))
893 rt->rt_nhn_alive--;
894
895 rtnh = rtnh_next(rtnh, &remaining);
896 nhs++;
897 } endfor_nexthops(rt);
898
899 rt->rt_nhn = nhs;
900
901 return 0;
902
903 errout:
904 return err;
905 }
906
907 static bool mpls_label_ok(struct net *net, unsigned int index,
908 struct netlink_ext_ack *extack)
909 {
910 /* Reserved labels may not be set */
911 if (index < MPLS_LABEL_FIRST_UNRESERVED) {
912 NL_SET_ERR_MSG(extack,
913 "Invalid label - must be MPLS_LABEL_FIRST_UNRESERVED or higher");
914 return false;
915 }
916
917 /* The full 20 bit range may not be supported. */
918 if (index >= net->mpls.platform_labels) {
919 NL_SET_ERR_MSG(extack,
920 "Label >= configured maximum in platform_labels");
921 return false;
922 }
923
924 return true;
925 }
926
927 static int mpls_route_add(struct mpls_route_config *cfg,
928 struct netlink_ext_ack *extack)
929 {
930 struct mpls_route __rcu **platform_label;
931 struct net *net = cfg->rc_nlinfo.nl_net;
932 struct mpls_route *rt, *old;
933 int err = -EINVAL;
934 u8 max_via_alen;
935 unsigned index;
936 u8 max_labels;
937 u8 nhs;
938
939 index = cfg->rc_label;
940
941 /* If a label was not specified during insert pick one */
942 if ((index == LABEL_NOT_SPECIFIED) &&
943 (cfg->rc_nlflags & NLM_F_CREATE)) {
944 index = find_free_label(net);
945 }
946
947 if (!mpls_label_ok(net, index, extack))
948 goto errout;
949
950 /* Append makes no sense with mpls */
951 err = -EOPNOTSUPP;
952 if (cfg->rc_nlflags & NLM_F_APPEND) {
953 NL_SET_ERR_MSG(extack, "MPLS does not support route append");
954 goto errout;
955 }
956
957 err = -EEXIST;
958 platform_label = rtnl_dereference(net->mpls.platform_label);
959 old = rtnl_dereference(platform_label[index]);
960 if ((cfg->rc_nlflags & NLM_F_EXCL) && old)
961 goto errout;
962
963 err = -EEXIST;
964 if (!(cfg->rc_nlflags & NLM_F_REPLACE) && old)
965 goto errout;
966
967 err = -ENOENT;
968 if (!(cfg->rc_nlflags & NLM_F_CREATE) && !old)
969 goto errout;
970
971 err = -EINVAL;
972 if (cfg->rc_mp) {
973 nhs = mpls_count_nexthops(cfg->rc_mp, cfg->rc_mp_len,
974 cfg->rc_via_alen, &max_via_alen,
975 &max_labels);
976 } else {
977 max_via_alen = cfg->rc_via_alen;
978 max_labels = cfg->rc_output_labels;
979 nhs = 1;
980 }
981
982 if (nhs == 0) {
983 NL_SET_ERR_MSG(extack, "Route does not contain a nexthop");
984 goto errout;
985 }
986
987 err = -ENOMEM;
988 rt = mpls_rt_alloc(nhs, max_via_alen, max_labels);
989 if (IS_ERR(rt)) {
990 err = PTR_ERR(rt);
991 goto errout;
992 }
993
994 rt->rt_protocol = cfg->rc_protocol;
995 rt->rt_payload_type = cfg->rc_payload_type;
996 rt->rt_ttl_propagate = cfg->rc_ttl_propagate;
997
998 if (cfg->rc_mp)
999 err = mpls_nh_build_multi(cfg, rt, max_labels, extack);
1000 else
1001 err = mpls_nh_build_from_cfg(cfg, rt);
1002 if (err)
1003 goto freert;
1004
1005 mpls_route_update(net, index, rt, &cfg->rc_nlinfo);
1006
1007 return 0;
1008
1009 freert:
1010 mpls_rt_free(rt);
1011 errout:
1012 return err;
1013 }
1014
1015 static int mpls_route_del(struct mpls_route_config *cfg,
1016 struct netlink_ext_ack *extack)
1017 {
1018 struct net *net = cfg->rc_nlinfo.nl_net;
1019 unsigned index;
1020 int err = -EINVAL;
1021
1022 index = cfg->rc_label;
1023
1024 if (!mpls_label_ok(net, index, extack))
1025 goto errout;
1026
1027 mpls_route_update(net, index, NULL, &cfg->rc_nlinfo);
1028
1029 err = 0;
1030 errout:
1031 return err;
1032 }
1033
1034 static void mpls_get_stats(struct mpls_dev *mdev,
1035 struct mpls_link_stats *stats)
1036 {
1037 struct mpls_pcpu_stats *p;
1038 int i;
1039
1040 memset(stats, 0, sizeof(*stats));
1041
1042 for_each_possible_cpu(i) {
1043 struct mpls_link_stats local;
1044 unsigned int start;
1045
1046 p = per_cpu_ptr(mdev->stats, i);
1047 do {
1048 start = u64_stats_fetch_begin(&p->syncp);
1049 local = p->stats;
1050 } while (u64_stats_fetch_retry(&p->syncp, start));
1051
1052 stats->rx_packets += local.rx_packets;
1053 stats->rx_bytes += local.rx_bytes;
1054 stats->tx_packets += local.tx_packets;
1055 stats->tx_bytes += local.tx_bytes;
1056 stats->rx_errors += local.rx_errors;
1057 stats->tx_errors += local.tx_errors;
1058 stats->rx_dropped += local.rx_dropped;
1059 stats->tx_dropped += local.tx_dropped;
1060 stats->rx_noroute += local.rx_noroute;
1061 }
1062 }
1063
1064 static int mpls_fill_stats_af(struct sk_buff *skb,
1065 const struct net_device *dev)
1066 {
1067 struct mpls_link_stats *stats;
1068 struct mpls_dev *mdev;
1069 struct nlattr *nla;
1070
1071 mdev = mpls_dev_get(dev);
1072 if (!mdev)
1073 return -ENODATA;
1074
1075 nla = nla_reserve_64bit(skb, MPLS_STATS_LINK,
1076 sizeof(struct mpls_link_stats),
1077 MPLS_STATS_UNSPEC);
1078 if (!nla)
1079 return -EMSGSIZE;
1080
1081 stats = nla_data(nla);
1082 mpls_get_stats(mdev, stats);
1083
1084 return 0;
1085 }
1086
1087 static size_t mpls_get_stats_af_size(const struct net_device *dev)
1088 {
1089 struct mpls_dev *mdev;
1090
1091 mdev = mpls_dev_get(dev);
1092 if (!mdev)
1093 return 0;
1094
1095 return nla_total_size_64bit(sizeof(struct mpls_link_stats));
1096 }
1097
1098 static int mpls_netconf_fill_devconf(struct sk_buff *skb, struct mpls_dev *mdev,
1099 u32 portid, u32 seq, int event,
1100 unsigned int flags, int type)
1101 {
1102 struct nlmsghdr *nlh;
1103 struct netconfmsg *ncm;
1104 bool all = false;
1105
1106 nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
1107 flags);
1108 if (!nlh)
1109 return -EMSGSIZE;
1110
1111 if (type == NETCONFA_ALL)
1112 all = true;
1113
1114 ncm = nlmsg_data(nlh);
1115 ncm->ncm_family = AF_MPLS;
1116
1117 if (nla_put_s32(skb, NETCONFA_IFINDEX, mdev->dev->ifindex) < 0)
1118 goto nla_put_failure;
1119
1120 if ((all || type == NETCONFA_INPUT) &&
1121 nla_put_s32(skb, NETCONFA_INPUT,
1122 mdev->input_enabled) < 0)
1123 goto nla_put_failure;
1124
1125 nlmsg_end(skb, nlh);
1126 return 0;
1127
1128 nla_put_failure:
1129 nlmsg_cancel(skb, nlh);
1130 return -EMSGSIZE;
1131 }
1132
1133 static int mpls_netconf_msgsize_devconf(int type)
1134 {
1135 int size = NLMSG_ALIGN(sizeof(struct netconfmsg))
1136 + nla_total_size(4); /* NETCONFA_IFINDEX */
1137 bool all = false;
1138
1139 if (type == NETCONFA_ALL)
1140 all = true;
1141
1142 if (all || type == NETCONFA_INPUT)
1143 size += nla_total_size(4);
1144
1145 return size;
1146 }
1147
1148 static void mpls_netconf_notify_devconf(struct net *net, int event,
1149 int type, struct mpls_dev *mdev)
1150 {
1151 struct sk_buff *skb;
1152 int err = -ENOBUFS;
1153
1154 skb = nlmsg_new(mpls_netconf_msgsize_devconf(type), GFP_KERNEL);
1155 if (!skb)
1156 goto errout;
1157
1158 err = mpls_netconf_fill_devconf(skb, mdev, 0, 0, event, 0, type);
1159 if (err < 0) {
1160 /* -EMSGSIZE implies BUG in mpls_netconf_msgsize_devconf() */
1161 WARN_ON(err == -EMSGSIZE);
1162 kfree_skb(skb);
1163 goto errout;
1164 }
1165
1166 rtnl_notify(skb, net, 0, RTNLGRP_MPLS_NETCONF, NULL, GFP_KERNEL);
1167 return;
1168 errout:
1169 if (err < 0)
1170 rtnl_set_sk_err(net, RTNLGRP_MPLS_NETCONF, err);
1171 }
1172
1173 static const struct nla_policy devconf_mpls_policy[NETCONFA_MAX + 1] = {
1174 [NETCONFA_IFINDEX] = { .len = sizeof(int) },
1175 };
1176
1177 static int mpls_netconf_get_devconf(struct sk_buff *in_skb,
1178 struct nlmsghdr *nlh,
1179 struct netlink_ext_ack *extack)
1180 {
1181 struct net *net = sock_net(in_skb->sk);
1182 struct nlattr *tb[NETCONFA_MAX + 1];
1183 struct netconfmsg *ncm;
1184 struct net_device *dev;
1185 struct mpls_dev *mdev;
1186 struct sk_buff *skb;
1187 int ifindex;
1188 int err;
1189
1190 err = nlmsg_parse(nlh, sizeof(*ncm), tb, NETCONFA_MAX,
1191 devconf_mpls_policy, NULL);
1192 if (err < 0)
1193 goto errout;
1194
1195 err = -EINVAL;
1196 if (!tb[NETCONFA_IFINDEX])
1197 goto errout;
1198
1199 ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
1200 dev = __dev_get_by_index(net, ifindex);
1201 if (!dev)
1202 goto errout;
1203
1204 mdev = mpls_dev_get(dev);
1205 if (!mdev)
1206 goto errout;
1207
1208 err = -ENOBUFS;
1209 skb = nlmsg_new(mpls_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL);
1210 if (!skb)
1211 goto errout;
1212
1213 err = mpls_netconf_fill_devconf(skb, mdev,
1214 NETLINK_CB(in_skb).portid,
1215 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
1216 NETCONFA_ALL);
1217 if (err < 0) {
1218 /* -EMSGSIZE implies BUG in mpls_netconf_msgsize_devconf() */
1219 WARN_ON(err == -EMSGSIZE);
1220 kfree_skb(skb);
1221 goto errout;
1222 }
1223 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
1224 errout:
1225 return err;
1226 }
1227
1228 static int mpls_netconf_dump_devconf(struct sk_buff *skb,
1229 struct netlink_callback *cb)
1230 {
1231 struct net *net = sock_net(skb->sk);
1232 struct hlist_head *head;
1233 struct net_device *dev;
1234 struct mpls_dev *mdev;
1235 int idx, s_idx;
1236 int h, s_h;
1237
1238 s_h = cb->args[0];
1239 s_idx = idx = cb->args[1];
1240
1241 for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
1242 idx = 0;
1243 head = &net->dev_index_head[h];
1244 rcu_read_lock();
1245 cb->seq = net->dev_base_seq;
1246 hlist_for_each_entry_rcu(dev, head, index_hlist) {
1247 if (idx < s_idx)
1248 goto cont;
1249 mdev = mpls_dev_get(dev);
1250 if (!mdev)
1251 goto cont;
1252 if (mpls_netconf_fill_devconf(skb, mdev,
1253 NETLINK_CB(cb->skb).portid,
1254 cb->nlh->nlmsg_seq,
1255 RTM_NEWNETCONF,
1256 NLM_F_MULTI,
1257 NETCONFA_ALL) < 0) {
1258 rcu_read_unlock();
1259 goto done;
1260 }
1261 nl_dump_check_consistent(cb, nlmsg_hdr(skb));
1262 cont:
1263 idx++;
1264 }
1265 rcu_read_unlock();
1266 }
1267 done:
1268 cb->args[0] = h;
1269 cb->args[1] = idx;
1270
1271 return skb->len;
1272 }
1273
1274 #define MPLS_PERDEV_SYSCTL_OFFSET(field) \
1275 (&((struct mpls_dev *)0)->field)
1276
1277 static int mpls_conf_proc(struct ctl_table *ctl, int write,
1278 void __user *buffer,
1279 size_t *lenp, loff_t *ppos)
1280 {
1281 int oval = *(int *)ctl->data;
1282 int ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
1283
1284 if (write) {
1285 struct mpls_dev *mdev = ctl->extra1;
1286 int i = (int *)ctl->data - (int *)mdev;
1287 struct net *net = ctl->extra2;
1288 int val = *(int *)ctl->data;
1289
1290 if (i == offsetof(struct mpls_dev, input_enabled) &&
1291 val != oval) {
1292 mpls_netconf_notify_devconf(net, RTM_NEWNETCONF,
1293 NETCONFA_INPUT, mdev);
1294 }
1295 }
1296
1297 return ret;
1298 }
1299
1300 static const struct ctl_table mpls_dev_table[] = {
1301 {
1302 .procname = "input",
1303 .maxlen = sizeof(int),
1304 .mode = 0644,
1305 .proc_handler = mpls_conf_proc,
1306 .data = MPLS_PERDEV_SYSCTL_OFFSET(input_enabled),
1307 },
1308 { }
1309 };
1310
1311 static int mpls_dev_sysctl_register(struct net_device *dev,
1312 struct mpls_dev *mdev)
1313 {
1314 char path[sizeof("net/mpls/conf/") + IFNAMSIZ];
1315 struct net *net = dev_net(dev);
1316 struct ctl_table *table;
1317 int i;
1318
1319 table = kmemdup(&mpls_dev_table, sizeof(mpls_dev_table), GFP_KERNEL);
1320 if (!table)
1321 goto out;
1322
1323 /* Table data contains only offsets relative to the base of
1324 * the mdev at this point, so make them absolute.
1325 */
1326 for (i = 0; i < ARRAY_SIZE(mpls_dev_table); i++) {
1327 table[i].data = (char *)mdev + (uintptr_t)table[i].data;
1328 table[i].extra1 = mdev;
1329 table[i].extra2 = net;
1330 }
1331
1332 snprintf(path, sizeof(path), "net/mpls/conf/%s", dev->name);
1333
1334 mdev->sysctl = register_net_sysctl(net, path, table);
1335 if (!mdev->sysctl)
1336 goto free;
1337
1338 mpls_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL, mdev);
1339 return 0;
1340
1341 free:
1342 kfree(table);
1343 out:
1344 return -ENOBUFS;
1345 }
1346
1347 static void mpls_dev_sysctl_unregister(struct net_device *dev,
1348 struct mpls_dev *mdev)
1349 {
1350 struct net *net = dev_net(dev);
1351 struct ctl_table *table;
1352
1353 table = mdev->sysctl->ctl_table_arg;
1354 unregister_net_sysctl_table(mdev->sysctl);
1355 kfree(table);
1356
1357 mpls_netconf_notify_devconf(net, RTM_DELNETCONF, 0, mdev);
1358 }
1359
1360 static struct mpls_dev *mpls_add_dev(struct net_device *dev)
1361 {
1362 struct mpls_dev *mdev;
1363 int err = -ENOMEM;
1364 int i;
1365
1366 ASSERT_RTNL();
1367
1368 mdev = kzalloc(sizeof(*mdev), GFP_KERNEL);
1369 if (!mdev)
1370 return ERR_PTR(err);
1371
1372 mdev->stats = alloc_percpu(struct mpls_pcpu_stats);
1373 if (!mdev->stats)
1374 goto free;
1375
1376 for_each_possible_cpu(i) {
1377 struct mpls_pcpu_stats *mpls_stats;
1378
1379 mpls_stats = per_cpu_ptr(mdev->stats, i);
1380 u64_stats_init(&mpls_stats->syncp);
1381 }
1382
1383 mdev->dev = dev;
1384
1385 err = mpls_dev_sysctl_register(dev, mdev);
1386 if (err)
1387 goto free;
1388
1389 rcu_assign_pointer(dev->mpls_ptr, mdev);
1390
1391 return mdev;
1392
1393 free:
1394 free_percpu(mdev->stats);
1395 kfree(mdev);
1396 return ERR_PTR(err);
1397 }
1398
1399 static void mpls_dev_destroy_rcu(struct rcu_head *head)
1400 {
1401 struct mpls_dev *mdev = container_of(head, struct mpls_dev, rcu);
1402
1403 free_percpu(mdev->stats);
1404 kfree(mdev);
1405 }
1406
1407 static void mpls_ifdown(struct net_device *dev, int event)
1408 {
1409 struct mpls_route __rcu **platform_label;
1410 struct net *net = dev_net(dev);
1411 u8 alive, deleted;
1412 unsigned index;
1413
1414 platform_label = rtnl_dereference(net->mpls.platform_label);
1415 for (index = 0; index < net->mpls.platform_labels; index++) {
1416 struct mpls_route *rt = rtnl_dereference(platform_label[index]);
1417
1418 if (!rt)
1419 continue;
1420
1421 alive = 0;
1422 deleted = 0;
1423 change_nexthops(rt) {
1424 unsigned int nh_flags = nh->nh_flags;
1425
1426 if (rtnl_dereference(nh->nh_dev) != dev)
1427 goto next;
1428
1429 switch (event) {
1430 case NETDEV_DOWN:
1431 case NETDEV_UNREGISTER:
1432 nh_flags |= RTNH_F_DEAD;
1433 /* fall through */
1434 case NETDEV_CHANGE:
1435 nh_flags |= RTNH_F_LINKDOWN;
1436 break;
1437 }
1438 if (event == NETDEV_UNREGISTER)
1439 RCU_INIT_POINTER(nh->nh_dev, NULL);
1440
1441 if (nh->nh_flags != nh_flags)
1442 WRITE_ONCE(nh->nh_flags, nh_flags);
1443 next:
1444 if (!(nh_flags & (RTNH_F_DEAD | RTNH_F_LINKDOWN)))
1445 alive++;
1446 if (!rtnl_dereference(nh->nh_dev))
1447 deleted++;
1448 } endfor_nexthops(rt);
1449
1450 WRITE_ONCE(rt->rt_nhn_alive, alive);
1451
1452 /* if there are no more nexthops, delete the route */
1453 if (event == NETDEV_UNREGISTER && deleted == rt->rt_nhn)
1454 mpls_route_update(net, index, NULL, NULL);
1455 }
1456 }
1457
1458 static void mpls_ifup(struct net_device *dev, unsigned int flags)
1459 {
1460 struct mpls_route __rcu **platform_label;
1461 struct net *net = dev_net(dev);
1462 unsigned index;
1463 u8 alive;
1464
1465 platform_label = rtnl_dereference(net->mpls.platform_label);
1466 for (index = 0; index < net->mpls.platform_labels; index++) {
1467 struct mpls_route *rt = rtnl_dereference(platform_label[index]);
1468
1469 if (!rt)
1470 continue;
1471
1472 alive = 0;
1473 change_nexthops(rt) {
1474 unsigned int nh_flags = nh->nh_flags;
1475 struct net_device *nh_dev =
1476 rtnl_dereference(nh->nh_dev);
1477
1478 if (!(nh_flags & flags)) {
1479 alive++;
1480 continue;
1481 }
1482 if (nh_dev != dev)
1483 continue;
1484 alive++;
1485 nh_flags &= ~flags;
1486 WRITE_ONCE(nh->nh_flags, nh_flags);
1487 } endfor_nexthops(rt);
1488
1489 WRITE_ONCE(rt->rt_nhn_alive, alive);
1490 }
1491 }
1492
1493 static int mpls_dev_notify(struct notifier_block *this, unsigned long event,
1494 void *ptr)
1495 {
1496 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1497 struct mpls_dev *mdev;
1498 unsigned int flags;
1499
1500 if (event == NETDEV_REGISTER) {
1501 /* For now just support Ethernet, IPGRE, SIT and IPIP devices */
1502 if (dev->type == ARPHRD_ETHER ||
1503 dev->type == ARPHRD_LOOPBACK ||
1504 dev->type == ARPHRD_IPGRE ||
1505 dev->type == ARPHRD_SIT ||
1506 dev->type == ARPHRD_TUNNEL) {
1507 mdev = mpls_add_dev(dev);
1508 if (IS_ERR(mdev))
1509 return notifier_from_errno(PTR_ERR(mdev));
1510 }
1511 return NOTIFY_OK;
1512 }
1513
1514 mdev = mpls_dev_get(dev);
1515 if (!mdev)
1516 return NOTIFY_OK;
1517
1518 switch (event) {
1519 case NETDEV_DOWN:
1520 mpls_ifdown(dev, event);
1521 break;
1522 case NETDEV_UP:
1523 flags = dev_get_flags(dev);
1524 if (flags & (IFF_RUNNING | IFF_LOWER_UP))
1525 mpls_ifup(dev, RTNH_F_DEAD | RTNH_F_LINKDOWN);
1526 else
1527 mpls_ifup(dev, RTNH_F_DEAD);
1528 break;
1529 case NETDEV_CHANGE:
1530 flags = dev_get_flags(dev);
1531 if (flags & (IFF_RUNNING | IFF_LOWER_UP))
1532 mpls_ifup(dev, RTNH_F_DEAD | RTNH_F_LINKDOWN);
1533 else
1534 mpls_ifdown(dev, event);
1535 break;
1536 case NETDEV_UNREGISTER:
1537 mpls_ifdown(dev, event);
1538 mdev = mpls_dev_get(dev);
1539 if (mdev) {
1540 mpls_dev_sysctl_unregister(dev, mdev);
1541 RCU_INIT_POINTER(dev->mpls_ptr, NULL);
1542 call_rcu(&mdev->rcu, mpls_dev_destroy_rcu);
1543 }
1544 break;
1545 case NETDEV_CHANGENAME:
1546 mdev = mpls_dev_get(dev);
1547 if (mdev) {
1548 int err;
1549
1550 mpls_dev_sysctl_unregister(dev, mdev);
1551 err = mpls_dev_sysctl_register(dev, mdev);
1552 if (err)
1553 return notifier_from_errno(err);
1554 }
1555 break;
1556 }
1557 return NOTIFY_OK;
1558 }
1559
1560 static struct notifier_block mpls_dev_notifier = {
1561 .notifier_call = mpls_dev_notify,
1562 };
1563
1564 static int nla_put_via(struct sk_buff *skb,
1565 u8 table, const void *addr, int alen)
1566 {
1567 static const int table_to_family[NEIGH_NR_TABLES + 1] = {
1568 AF_INET, AF_INET6, AF_DECnet, AF_PACKET,
1569 };
1570 struct nlattr *nla;
1571 struct rtvia *via;
1572 int family = AF_UNSPEC;
1573
1574 nla = nla_reserve(skb, RTA_VIA, alen + 2);
1575 if (!nla)
1576 return -EMSGSIZE;
1577
1578 if (table <= NEIGH_NR_TABLES)
1579 family = table_to_family[table];
1580
1581 via = nla_data(nla);
1582 via->rtvia_family = family;
1583 memcpy(via->rtvia_addr, addr, alen);
1584 return 0;
1585 }
1586
1587 int nla_put_labels(struct sk_buff *skb, int attrtype,
1588 u8 labels, const u32 label[])
1589 {
1590 struct nlattr *nla;
1591 struct mpls_shim_hdr *nla_label;
1592 bool bos;
1593 int i;
1594 nla = nla_reserve(skb, attrtype, labels*4);
1595 if (!nla)
1596 return -EMSGSIZE;
1597
1598 nla_label = nla_data(nla);
1599 bos = true;
1600 for (i = labels - 1; i >= 0; i--) {
1601 nla_label[i] = mpls_entry_encode(label[i], 0, 0, bos);
1602 bos = false;
1603 }
1604
1605 return 0;
1606 }
1607 EXPORT_SYMBOL_GPL(nla_put_labels);
1608
1609 int nla_get_labels(const struct nlattr *nla, u8 max_labels, u8 *labels,
1610 u32 label[], struct netlink_ext_ack *extack)
1611 {
1612 unsigned len = nla_len(nla);
1613 struct mpls_shim_hdr *nla_label;
1614 u8 nla_labels;
1615 bool bos;
1616 int i;
1617
1618 /* len needs to be an even multiple of 4 (the label size). Number
1619 * of labels is a u8 so check for overflow.
1620 */
1621 if (len & 3 || len / 4 > 255) {
1622 NL_SET_ERR_MSG_ATTR(extack, nla,
1623 "Invalid length for labels attribute");
1624 return -EINVAL;
1625 }
1626
1627 /* Limit the number of new labels allowed */
1628 nla_labels = len/4;
1629 if (nla_labels > max_labels) {
1630 NL_SET_ERR_MSG(extack, "Too many labels");
1631 return -EINVAL;
1632 }
1633
1634 /* when label == NULL, caller wants number of labels */
1635 if (!label)
1636 goto out;
1637
1638 nla_label = nla_data(nla);
1639 bos = true;
1640 for (i = nla_labels - 1; i >= 0; i--, bos = false) {
1641 struct mpls_entry_decoded dec;
1642 dec = mpls_entry_decode(nla_label + i);
1643
1644 /* Ensure the bottom of stack flag is properly set
1645 * and ttl and tc are both clear.
1646 */
1647 if (dec.ttl) {
1648 NL_SET_ERR_MSG_ATTR(extack, nla,
1649 "TTL in label must be 0");
1650 return -EINVAL;
1651 }
1652
1653 if (dec.tc) {
1654 NL_SET_ERR_MSG_ATTR(extack, nla,
1655 "Traffic class in label must be 0");
1656 return -EINVAL;
1657 }
1658
1659 if (dec.bos != bos) {
1660 NL_SET_BAD_ATTR(extack, nla);
1661 if (bos) {
1662 NL_SET_ERR_MSG(extack,
1663 "BOS bit must be set in first label");
1664 } else {
1665 NL_SET_ERR_MSG(extack,
1666 "BOS bit can only be set in first label");
1667 }
1668 return -EINVAL;
1669 }
1670
1671 switch (dec.label) {
1672 case MPLS_LABEL_IMPLNULL:
1673 /* RFC3032: This is a label that an LSR may
1674 * assign and distribute, but which never
1675 * actually appears in the encapsulation.
1676 */
1677 NL_SET_ERR_MSG_ATTR(extack, nla,
1678 "Implicit NULL Label (3) can not be used in encapsulation");
1679 return -EINVAL;
1680 }
1681
1682 label[i] = dec.label;
1683 }
1684 out:
1685 *labels = nla_labels;
1686 return 0;
1687 }
1688 EXPORT_SYMBOL_GPL(nla_get_labels);
1689
1690 static int rtm_to_route_config(struct sk_buff *skb,
1691 struct nlmsghdr *nlh,
1692 struct mpls_route_config *cfg,
1693 struct netlink_ext_ack *extack)
1694 {
1695 struct rtmsg *rtm;
1696 struct nlattr *tb[RTA_MAX+1];
1697 int index;
1698 int err;
1699
1700 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_mpls_policy,
1701 extack);
1702 if (err < 0)
1703 goto errout;
1704
1705 err = -EINVAL;
1706 rtm = nlmsg_data(nlh);
1707
1708 if (rtm->rtm_family != AF_MPLS) {
1709 NL_SET_ERR_MSG(extack, "Invalid address family in rtmsg");
1710 goto errout;
1711 }
1712 if (rtm->rtm_dst_len != 20) {
1713 NL_SET_ERR_MSG(extack, "rtm_dst_len must be 20 for MPLS");
1714 goto errout;
1715 }
1716 if (rtm->rtm_src_len != 0) {
1717 NL_SET_ERR_MSG(extack, "rtm_src_len must be 0 for MPLS");
1718 goto errout;
1719 }
1720 if (rtm->rtm_tos != 0) {
1721 NL_SET_ERR_MSG(extack, "rtm_tos must be 0 for MPLS");
1722 goto errout;
1723 }
1724 if (rtm->rtm_table != RT_TABLE_MAIN) {
1725 NL_SET_ERR_MSG(extack,
1726 "MPLS only supports the main route table");
1727 goto errout;
1728 }
1729 /* Any value is acceptable for rtm_protocol */
1730
1731 /* As mpls uses destination specific addresses
1732 * (or source specific address in the case of multicast)
1733 * all addresses have universal scope.
1734 */
1735 if (rtm->rtm_scope != RT_SCOPE_UNIVERSE) {
1736 NL_SET_ERR_MSG(extack,
1737 "Invalid route scope - MPLS only supports UNIVERSE");
1738 goto errout;
1739 }
1740 if (rtm->rtm_type != RTN_UNICAST) {
1741 NL_SET_ERR_MSG(extack,
1742 "Invalid route type - MPLS only supports UNICAST");
1743 goto errout;
1744 }
1745 if (rtm->rtm_flags != 0) {
1746 NL_SET_ERR_MSG(extack, "rtm_flags must be 0 for MPLS");
1747 goto errout;
1748 }
1749
1750 cfg->rc_label = LABEL_NOT_SPECIFIED;
1751 cfg->rc_protocol = rtm->rtm_protocol;
1752 cfg->rc_via_table = MPLS_NEIGH_TABLE_UNSPEC;
1753 cfg->rc_ttl_propagate = MPLS_TTL_PROP_DEFAULT;
1754 cfg->rc_nlflags = nlh->nlmsg_flags;
1755 cfg->rc_nlinfo.portid = NETLINK_CB(skb).portid;
1756 cfg->rc_nlinfo.nlh = nlh;
1757 cfg->rc_nlinfo.nl_net = sock_net(skb->sk);
1758
1759 for (index = 0; index <= RTA_MAX; index++) {
1760 struct nlattr *nla = tb[index];
1761 if (!nla)
1762 continue;
1763
1764 switch (index) {
1765 case RTA_OIF:
1766 cfg->rc_ifindex = nla_get_u32(nla);
1767 break;
1768 case RTA_NEWDST:
1769 if (nla_get_labels(nla, MAX_NEW_LABELS,
1770 &cfg->rc_output_labels,
1771 cfg->rc_output_label, extack))
1772 goto errout;
1773 break;
1774 case RTA_DST:
1775 {
1776 u8 label_count;
1777 if (nla_get_labels(nla, 1, &label_count,
1778 &cfg->rc_label, extack))
1779 goto errout;
1780
1781 if (!mpls_label_ok(cfg->rc_nlinfo.nl_net,
1782 cfg->rc_label, extack))
1783 goto errout;
1784 break;
1785 }
1786 case RTA_VIA:
1787 {
1788 if (nla_get_via(nla, &cfg->rc_via_alen,
1789 &cfg->rc_via_table, cfg->rc_via,
1790 extack))
1791 goto errout;
1792 break;
1793 }
1794 case RTA_MULTIPATH:
1795 {
1796 cfg->rc_mp = nla_data(nla);
1797 cfg->rc_mp_len = nla_len(nla);
1798 break;
1799 }
1800 case RTA_TTL_PROPAGATE:
1801 {
1802 u8 ttl_propagate = nla_get_u8(nla);
1803
1804 if (ttl_propagate > 1) {
1805 NL_SET_ERR_MSG_ATTR(extack, nla,
1806 "RTA_TTL_PROPAGATE can only be 0 or 1");
1807 goto errout;
1808 }
1809 cfg->rc_ttl_propagate = ttl_propagate ?
1810 MPLS_TTL_PROP_ENABLED :
1811 MPLS_TTL_PROP_DISABLED;
1812 break;
1813 }
1814 default:
1815 NL_SET_ERR_MSG_ATTR(extack, nla, "Unknown attribute");
1816 /* Unsupported attribute */
1817 goto errout;
1818 }
1819 }
1820
1821 err = 0;
1822 errout:
1823 return err;
1824 }
1825
1826 static int mpls_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh,
1827 struct netlink_ext_ack *extack)
1828 {
1829 struct mpls_route_config *cfg;
1830 int err;
1831
1832 cfg = kzalloc(sizeof(*cfg), GFP_KERNEL);
1833 if (!cfg)
1834 return -ENOMEM;
1835
1836 err = rtm_to_route_config(skb, nlh, cfg, extack);
1837 if (err < 0)
1838 goto out;
1839
1840 err = mpls_route_del(cfg, extack);
1841 out:
1842 kfree(cfg);
1843
1844 return err;
1845 }
1846
1847
1848 static int mpls_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh,
1849 struct netlink_ext_ack *extack)
1850 {
1851 struct mpls_route_config *cfg;
1852 int err;
1853
1854 cfg = kzalloc(sizeof(*cfg), GFP_KERNEL);
1855 if (!cfg)
1856 return -ENOMEM;
1857
1858 err = rtm_to_route_config(skb, nlh, cfg, extack);
1859 if (err < 0)
1860 goto out;
1861
1862 err = mpls_route_add(cfg, extack);
1863 out:
1864 kfree(cfg);
1865
1866 return err;
1867 }
1868
1869 static int mpls_dump_route(struct sk_buff *skb, u32 portid, u32 seq, int event,
1870 u32 label, struct mpls_route *rt, int flags)
1871 {
1872 struct net_device *dev;
1873 struct nlmsghdr *nlh;
1874 struct rtmsg *rtm;
1875
1876 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*rtm), flags);
1877 if (nlh == NULL)
1878 return -EMSGSIZE;
1879
1880 rtm = nlmsg_data(nlh);
1881 rtm->rtm_family = AF_MPLS;
1882 rtm->rtm_dst_len = 20;
1883 rtm->rtm_src_len = 0;
1884 rtm->rtm_tos = 0;
1885 rtm->rtm_table = RT_TABLE_MAIN;
1886 rtm->rtm_protocol = rt->rt_protocol;
1887 rtm->rtm_scope = RT_SCOPE_UNIVERSE;
1888 rtm->rtm_type = RTN_UNICAST;
1889 rtm->rtm_flags = 0;
1890
1891 if (nla_put_labels(skb, RTA_DST, 1, &label))
1892 goto nla_put_failure;
1893
1894 if (rt->rt_ttl_propagate != MPLS_TTL_PROP_DEFAULT) {
1895 bool ttl_propagate =
1896 rt->rt_ttl_propagate == MPLS_TTL_PROP_ENABLED;
1897
1898 if (nla_put_u8(skb, RTA_TTL_PROPAGATE,
1899 ttl_propagate))
1900 goto nla_put_failure;
1901 }
1902 if (rt->rt_nhn == 1) {
1903 const struct mpls_nh *nh = rt->rt_nh;
1904
1905 if (nh->nh_labels &&
1906 nla_put_labels(skb, RTA_NEWDST, nh->nh_labels,
1907 nh->nh_label))
1908 goto nla_put_failure;
1909 if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC &&
1910 nla_put_via(skb, nh->nh_via_table, mpls_nh_via(rt, nh),
1911 nh->nh_via_alen))
1912 goto nla_put_failure;
1913 dev = rtnl_dereference(nh->nh_dev);
1914 if (dev && nla_put_u32(skb, RTA_OIF, dev->ifindex))
1915 goto nla_put_failure;
1916 if (nh->nh_flags & RTNH_F_LINKDOWN)
1917 rtm->rtm_flags |= RTNH_F_LINKDOWN;
1918 if (nh->nh_flags & RTNH_F_DEAD)
1919 rtm->rtm_flags |= RTNH_F_DEAD;
1920 } else {
1921 struct rtnexthop *rtnh;
1922 struct nlattr *mp;
1923 u8 linkdown = 0;
1924 u8 dead = 0;
1925
1926 mp = nla_nest_start(skb, RTA_MULTIPATH);
1927 if (!mp)
1928 goto nla_put_failure;
1929
1930 for_nexthops(rt) {
1931 dev = rtnl_dereference(nh->nh_dev);
1932 if (!dev)
1933 continue;
1934
1935 rtnh = nla_reserve_nohdr(skb, sizeof(*rtnh));
1936 if (!rtnh)
1937 goto nla_put_failure;
1938
1939 rtnh->rtnh_ifindex = dev->ifindex;
1940 if (nh->nh_flags & RTNH_F_LINKDOWN) {
1941 rtnh->rtnh_flags |= RTNH_F_LINKDOWN;
1942 linkdown++;
1943 }
1944 if (nh->nh_flags & RTNH_F_DEAD) {
1945 rtnh->rtnh_flags |= RTNH_F_DEAD;
1946 dead++;
1947 }
1948
1949 if (nh->nh_labels && nla_put_labels(skb, RTA_NEWDST,
1950 nh->nh_labels,
1951 nh->nh_label))
1952 goto nla_put_failure;
1953 if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC &&
1954 nla_put_via(skb, nh->nh_via_table,
1955 mpls_nh_via(rt, nh),
1956 nh->nh_via_alen))
1957 goto nla_put_failure;
1958
1959 /* length of rtnetlink header + attributes */
1960 rtnh->rtnh_len = nlmsg_get_pos(skb) - (void *)rtnh;
1961 } endfor_nexthops(rt);
1962
1963 if (linkdown == rt->rt_nhn)
1964 rtm->rtm_flags |= RTNH_F_LINKDOWN;
1965 if (dead == rt->rt_nhn)
1966 rtm->rtm_flags |= RTNH_F_DEAD;
1967
1968 nla_nest_end(skb, mp);
1969 }
1970
1971 nlmsg_end(skb, nlh);
1972 return 0;
1973
1974 nla_put_failure:
1975 nlmsg_cancel(skb, nlh);
1976 return -EMSGSIZE;
1977 }
1978
1979 static int mpls_dump_routes(struct sk_buff *skb, struct netlink_callback *cb)
1980 {
1981 struct net *net = sock_net(skb->sk);
1982 struct mpls_route __rcu **platform_label;
1983 size_t platform_labels;
1984 unsigned int index;
1985
1986 ASSERT_RTNL();
1987
1988 index = cb->args[0];
1989 if (index < MPLS_LABEL_FIRST_UNRESERVED)
1990 index = MPLS_LABEL_FIRST_UNRESERVED;
1991
1992 platform_label = rtnl_dereference(net->mpls.platform_label);
1993 platform_labels = net->mpls.platform_labels;
1994 for (; index < platform_labels; index++) {
1995 struct mpls_route *rt;
1996 rt = rtnl_dereference(platform_label[index]);
1997 if (!rt)
1998 continue;
1999
2000 if (mpls_dump_route(skb, NETLINK_CB(cb->skb).portid,
2001 cb->nlh->nlmsg_seq, RTM_NEWROUTE,
2002 index, rt, NLM_F_MULTI) < 0)
2003 break;
2004 }
2005 cb->args[0] = index;
2006
2007 return skb->len;
2008 }
2009
2010 static inline size_t lfib_nlmsg_size(struct mpls_route *rt)
2011 {
2012 size_t payload =
2013 NLMSG_ALIGN(sizeof(struct rtmsg))
2014 + nla_total_size(4) /* RTA_DST */
2015 + nla_total_size(1); /* RTA_TTL_PROPAGATE */
2016
2017 if (rt->rt_nhn == 1) {
2018 struct mpls_nh *nh = rt->rt_nh;
2019
2020 if (nh->nh_dev)
2021 payload += nla_total_size(4); /* RTA_OIF */
2022 if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC) /* RTA_VIA */
2023 payload += nla_total_size(2 + nh->nh_via_alen);
2024 if (nh->nh_labels) /* RTA_NEWDST */
2025 payload += nla_total_size(nh->nh_labels * 4);
2026 } else {
2027 /* each nexthop is packed in an attribute */
2028 size_t nhsize = 0;
2029
2030 for_nexthops(rt) {
2031 if (!rtnl_dereference(nh->nh_dev))
2032 continue;
2033 nhsize += nla_total_size(sizeof(struct rtnexthop));
2034 /* RTA_VIA */
2035 if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC)
2036 nhsize += nla_total_size(2 + nh->nh_via_alen);
2037 if (nh->nh_labels)
2038 nhsize += nla_total_size(nh->nh_labels * 4);
2039 } endfor_nexthops(rt);
2040 /* nested attribute */
2041 payload += nla_total_size(nhsize);
2042 }
2043
2044 return payload;
2045 }
2046
2047 static void rtmsg_lfib(int event, u32 label, struct mpls_route *rt,
2048 struct nlmsghdr *nlh, struct net *net, u32 portid,
2049 unsigned int nlm_flags)
2050 {
2051 struct sk_buff *skb;
2052 u32 seq = nlh ? nlh->nlmsg_seq : 0;
2053 int err = -ENOBUFS;
2054
2055 skb = nlmsg_new(lfib_nlmsg_size(rt), GFP_KERNEL);
2056 if (skb == NULL)
2057 goto errout;
2058
2059 err = mpls_dump_route(skb, portid, seq, event, label, rt, nlm_flags);
2060 if (err < 0) {
2061 /* -EMSGSIZE implies BUG in lfib_nlmsg_size */
2062 WARN_ON(err == -EMSGSIZE);
2063 kfree_skb(skb);
2064 goto errout;
2065 }
2066 rtnl_notify(skb, net, portid, RTNLGRP_MPLS_ROUTE, nlh, GFP_KERNEL);
2067
2068 return;
2069 errout:
2070 if (err < 0)
2071 rtnl_set_sk_err(net, RTNLGRP_MPLS_ROUTE, err);
2072 }
2073
2074 static int mpls_getroute(struct sk_buff *in_skb, struct nlmsghdr *in_nlh,
2075 struct netlink_ext_ack *extack)
2076 {
2077 struct net *net = sock_net(in_skb->sk);
2078 u32 portid = NETLINK_CB(in_skb).portid;
2079 u32 in_label = LABEL_NOT_SPECIFIED;
2080 struct nlattr *tb[RTA_MAX + 1];
2081 u32 labels[MAX_NEW_LABELS];
2082 struct mpls_shim_hdr *hdr;
2083 unsigned int hdr_size = 0;
2084 struct net_device *dev;
2085 struct mpls_route *rt;
2086 struct rtmsg *rtm, *r;
2087 struct nlmsghdr *nlh;
2088 struct sk_buff *skb;
2089 struct mpls_nh *nh;
2090 u8 n_labels;
2091 int err;
2092
2093 err = nlmsg_parse(in_nlh, sizeof(*rtm), tb, RTA_MAX,
2094 rtm_mpls_policy, extack);
2095 if (err < 0)
2096 goto errout;
2097
2098 rtm = nlmsg_data(in_nlh);
2099
2100 if (tb[RTA_DST]) {
2101 u8 label_count;
2102
2103 if (nla_get_labels(tb[RTA_DST], 1, &label_count,
2104 &in_label, extack)) {
2105 err = -EINVAL;
2106 goto errout;
2107 }
2108
2109 if (!mpls_label_ok(net, in_label, extack)) {
2110 err = -EINVAL;
2111 goto errout;
2112 }
2113 }
2114
2115 rt = mpls_route_input_rcu(net, in_label);
2116 if (!rt) {
2117 err = -ENETUNREACH;
2118 goto errout;
2119 }
2120
2121 if (rtm->rtm_flags & RTM_F_FIB_MATCH) {
2122 skb = nlmsg_new(lfib_nlmsg_size(rt), GFP_KERNEL);
2123 if (!skb) {
2124 err = -ENOBUFS;
2125 goto errout;
2126 }
2127
2128 err = mpls_dump_route(skb, portid, in_nlh->nlmsg_seq,
2129 RTM_NEWROUTE, in_label, rt, 0);
2130 if (err < 0) {
2131 /* -EMSGSIZE implies BUG in lfib_nlmsg_size */
2132 WARN_ON(err == -EMSGSIZE);
2133 goto errout_free;
2134 }
2135
2136 return rtnl_unicast(skb, net, portid);
2137 }
2138
2139 if (tb[RTA_NEWDST]) {
2140 if (nla_get_labels(tb[RTA_NEWDST], MAX_NEW_LABELS, &n_labels,
2141 labels, extack) != 0) {
2142 err = -EINVAL;
2143 goto errout;
2144 }
2145
2146 hdr_size = n_labels * sizeof(struct mpls_shim_hdr);
2147 }
2148
2149 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2150 if (!skb) {
2151 err = -ENOBUFS;
2152 goto errout;
2153 }
2154
2155 skb->protocol = htons(ETH_P_MPLS_UC);
2156
2157 if (hdr_size) {
2158 bool bos;
2159 int i;
2160
2161 if (skb_cow(skb, hdr_size)) {
2162 err = -ENOBUFS;
2163 goto errout_free;
2164 }
2165
2166 skb_reserve(skb, hdr_size);
2167 skb_push(skb, hdr_size);
2168 skb_reset_network_header(skb);
2169
2170 /* Push new labels */
2171 hdr = mpls_hdr(skb);
2172 bos = true;
2173 for (i = n_labels - 1; i >= 0; i--) {
2174 hdr[i] = mpls_entry_encode(labels[i],
2175 1, 0, bos);
2176 bos = false;
2177 }
2178 }
2179
2180 nh = mpls_select_multipath(rt, skb);
2181 if (!nh) {
2182 err = -ENETUNREACH;
2183 goto errout_free;
2184 }
2185
2186 if (hdr_size) {
2187 skb_pull(skb, hdr_size);
2188 skb_reset_network_header(skb);
2189 }
2190
2191 nlh = nlmsg_put(skb, portid, in_nlh->nlmsg_seq,
2192 RTM_NEWROUTE, sizeof(*r), 0);
2193 if (!nlh) {
2194 err = -EMSGSIZE;
2195 goto errout_free;
2196 }
2197
2198 r = nlmsg_data(nlh);
2199 r->rtm_family = AF_MPLS;
2200 r->rtm_dst_len = 20;
2201 r->rtm_src_len = 0;
2202 r->rtm_table = RT_TABLE_MAIN;
2203 r->rtm_type = RTN_UNICAST;
2204 r->rtm_scope = RT_SCOPE_UNIVERSE;
2205 r->rtm_protocol = rt->rt_protocol;
2206 r->rtm_flags = 0;
2207
2208 if (nla_put_labels(skb, RTA_DST, 1, &in_label))
2209 goto nla_put_failure;
2210
2211 if (nh->nh_labels &&
2212 nla_put_labels(skb, RTA_NEWDST, nh->nh_labels,
2213 nh->nh_label))
2214 goto nla_put_failure;
2215
2216 if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC &&
2217 nla_put_via(skb, nh->nh_via_table, mpls_nh_via(rt, nh),
2218 nh->nh_via_alen))
2219 goto nla_put_failure;
2220 dev = rtnl_dereference(nh->nh_dev);
2221 if (dev && nla_put_u32(skb, RTA_OIF, dev->ifindex))
2222 goto nla_put_failure;
2223
2224 nlmsg_end(skb, nlh);
2225
2226 err = rtnl_unicast(skb, net, portid);
2227 errout:
2228 return err;
2229
2230 nla_put_failure:
2231 nlmsg_cancel(skb, nlh);
2232 err = -EMSGSIZE;
2233 errout_free:
2234 kfree_skb(skb);
2235 return err;
2236 }
2237
2238 static int resize_platform_label_table(struct net *net, size_t limit)
2239 {
2240 size_t size = sizeof(struct mpls_route *) * limit;
2241 size_t old_limit;
2242 size_t cp_size;
2243 struct mpls_route __rcu **labels = NULL, **old;
2244 struct mpls_route *rt0 = NULL, *rt2 = NULL;
2245 unsigned index;
2246
2247 if (size) {
2248 labels = kvzalloc(size, GFP_KERNEL);
2249 if (!labels)
2250 goto nolabels;
2251 }
2252
2253 /* In case the predefined labels need to be populated */
2254 if (limit > MPLS_LABEL_IPV4NULL) {
2255 struct net_device *lo = net->loopback_dev;
2256 rt0 = mpls_rt_alloc(1, lo->addr_len, 0);
2257 if (IS_ERR(rt0))
2258 goto nort0;
2259 RCU_INIT_POINTER(rt0->rt_nh->nh_dev, lo);
2260 rt0->rt_protocol = RTPROT_KERNEL;
2261 rt0->rt_payload_type = MPT_IPV4;
2262 rt0->rt_ttl_propagate = MPLS_TTL_PROP_DEFAULT;
2263 rt0->rt_nh->nh_via_table = NEIGH_LINK_TABLE;
2264 rt0->rt_nh->nh_via_alen = lo->addr_len;
2265 memcpy(__mpls_nh_via(rt0, rt0->rt_nh), lo->dev_addr,
2266 lo->addr_len);
2267 }
2268 if (limit > MPLS_LABEL_IPV6NULL) {
2269 struct net_device *lo = net->loopback_dev;
2270 rt2 = mpls_rt_alloc(1, lo->addr_len, 0);
2271 if (IS_ERR(rt2))
2272 goto nort2;
2273 RCU_INIT_POINTER(rt2->rt_nh->nh_dev, lo);
2274 rt2->rt_protocol = RTPROT_KERNEL;
2275 rt2->rt_payload_type = MPT_IPV6;
2276 rt2->rt_ttl_propagate = MPLS_TTL_PROP_DEFAULT;
2277 rt2->rt_nh->nh_via_table = NEIGH_LINK_TABLE;
2278 rt2->rt_nh->nh_via_alen = lo->addr_len;
2279 memcpy(__mpls_nh_via(rt2, rt2->rt_nh), lo->dev_addr,
2280 lo->addr_len);
2281 }
2282
2283 rtnl_lock();
2284 /* Remember the original table */
2285 old = rtnl_dereference(net->mpls.platform_label);
2286 old_limit = net->mpls.platform_labels;
2287
2288 /* Free any labels beyond the new table */
2289 for (index = limit; index < old_limit; index++)
2290 mpls_route_update(net, index, NULL, NULL);
2291
2292 /* Copy over the old labels */
2293 cp_size = size;
2294 if (old_limit < limit)
2295 cp_size = old_limit * sizeof(struct mpls_route *);
2296
2297 memcpy(labels, old, cp_size);
2298
2299 /* If needed set the predefined labels */
2300 if ((old_limit <= MPLS_LABEL_IPV6NULL) &&
2301 (limit > MPLS_LABEL_IPV6NULL)) {
2302 RCU_INIT_POINTER(labels[MPLS_LABEL_IPV6NULL], rt2);
2303 rt2 = NULL;
2304 }
2305
2306 if ((old_limit <= MPLS_LABEL_IPV4NULL) &&
2307 (limit > MPLS_LABEL_IPV4NULL)) {
2308 RCU_INIT_POINTER(labels[MPLS_LABEL_IPV4NULL], rt0);
2309 rt0 = NULL;
2310 }
2311
2312 /* Update the global pointers */
2313 net->mpls.platform_labels = limit;
2314 rcu_assign_pointer(net->mpls.platform_label, labels);
2315
2316 rtnl_unlock();
2317
2318 mpls_rt_free(rt2);
2319 mpls_rt_free(rt0);
2320
2321 if (old) {
2322 synchronize_rcu();
2323 kvfree(old);
2324 }
2325 return 0;
2326
2327 nort2:
2328 mpls_rt_free(rt0);
2329 nort0:
2330 kvfree(labels);
2331 nolabels:
2332 return -ENOMEM;
2333 }
2334
2335 static int mpls_platform_labels(struct ctl_table *table, int write,
2336 void __user *buffer, size_t *lenp, loff_t *ppos)
2337 {
2338 struct net *net = table->data;
2339 int platform_labels = net->mpls.platform_labels;
2340 int ret;
2341 struct ctl_table tmp = {
2342 .procname = table->procname,
2343 .data = &platform_labels,
2344 .maxlen = sizeof(int),
2345 .mode = table->mode,
2346 .extra1 = &zero,
2347 .extra2 = &label_limit,
2348 };
2349
2350 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
2351
2352 if (write && ret == 0)
2353 ret = resize_platform_label_table(net, platform_labels);
2354
2355 return ret;
2356 }
2357
2358 #define MPLS_NS_SYSCTL_OFFSET(field) \
2359 (&((struct net *)0)->field)
2360
2361 static const struct ctl_table mpls_table[] = {
2362 {
2363 .procname = "platform_labels",
2364 .data = NULL,
2365 .maxlen = sizeof(int),
2366 .mode = 0644,
2367 .proc_handler = mpls_platform_labels,
2368 },
2369 {
2370 .procname = "ip_ttl_propagate",
2371 .data = MPLS_NS_SYSCTL_OFFSET(mpls.ip_ttl_propagate),
2372 .maxlen = sizeof(int),
2373 .mode = 0644,
2374 .proc_handler = proc_dointvec_minmax,
2375 .extra1 = &zero,
2376 .extra2 = &one,
2377 },
2378 {
2379 .procname = "default_ttl",
2380 .data = MPLS_NS_SYSCTL_OFFSET(mpls.default_ttl),
2381 .maxlen = sizeof(int),
2382 .mode = 0644,
2383 .proc_handler = proc_dointvec_minmax,
2384 .extra1 = &one,
2385 .extra2 = &ttl_max,
2386 },
2387 { }
2388 };
2389
2390 static int mpls_net_init(struct net *net)
2391 {
2392 struct ctl_table *table;
2393 int i;
2394
2395 net->mpls.platform_labels = 0;
2396 net->mpls.platform_label = NULL;
2397 net->mpls.ip_ttl_propagate = 1;
2398 net->mpls.default_ttl = 255;
2399
2400 table = kmemdup(mpls_table, sizeof(mpls_table), GFP_KERNEL);
2401 if (table == NULL)
2402 return -ENOMEM;
2403
2404 /* Table data contains only offsets relative to the base of
2405 * the mdev at this point, so make them absolute.
2406 */
2407 for (i = 0; i < ARRAY_SIZE(mpls_table) - 1; i++)
2408 table[i].data = (char *)net + (uintptr_t)table[i].data;
2409
2410 net->mpls.ctl = register_net_sysctl(net, "net/mpls", table);
2411 if (net->mpls.ctl == NULL) {
2412 kfree(table);
2413 return -ENOMEM;
2414 }
2415
2416 return 0;
2417 }
2418
2419 static void mpls_net_exit(struct net *net)
2420 {
2421 struct mpls_route __rcu **platform_label;
2422 size_t platform_labels;
2423 struct ctl_table *table;
2424 unsigned int index;
2425
2426 table = net->mpls.ctl->ctl_table_arg;
2427 unregister_net_sysctl_table(net->mpls.ctl);
2428 kfree(table);
2429
2430 /* An rcu grace period has passed since there was a device in
2431 * the network namespace (and thus the last in flight packet)
2432 * left this network namespace. This is because
2433 * unregister_netdevice_many and netdev_run_todo has completed
2434 * for each network device that was in this network namespace.
2435 *
2436 * As such no additional rcu synchronization is necessary when
2437 * freeing the platform_label table.
2438 */
2439 rtnl_lock();
2440 platform_label = rtnl_dereference(net->mpls.platform_label);
2441 platform_labels = net->mpls.platform_labels;
2442 for (index = 0; index < platform_labels; index++) {
2443 struct mpls_route *rt = rtnl_dereference(platform_label[index]);
2444 RCU_INIT_POINTER(platform_label[index], NULL);
2445 mpls_notify_route(net, index, rt, NULL, NULL);
2446 mpls_rt_free(rt);
2447 }
2448 rtnl_unlock();
2449
2450 kvfree(platform_label);
2451 }
2452
2453 static struct pernet_operations mpls_net_ops = {
2454 .init = mpls_net_init,
2455 .exit = mpls_net_exit,
2456 };
2457
2458 static struct rtnl_af_ops mpls_af_ops __read_mostly = {
2459 .family = AF_MPLS,
2460 .fill_stats_af = mpls_fill_stats_af,
2461 .get_stats_af_size = mpls_get_stats_af_size,
2462 };
2463
2464 static int __init mpls_init(void)
2465 {
2466 int err;
2467
2468 BUILD_BUG_ON(sizeof(struct mpls_shim_hdr) != 4);
2469
2470 err = register_pernet_subsys(&mpls_net_ops);
2471 if (err)
2472 goto out;
2473
2474 err = register_netdevice_notifier(&mpls_dev_notifier);
2475 if (err)
2476 goto out_unregister_pernet;
2477
2478 dev_add_pack(&mpls_packet_type);
2479
2480 rtnl_af_register(&mpls_af_ops);
2481
2482 rtnl_register(PF_MPLS, RTM_NEWROUTE, mpls_rtm_newroute, NULL, 0);
2483 rtnl_register(PF_MPLS, RTM_DELROUTE, mpls_rtm_delroute, NULL, 0);
2484 rtnl_register(PF_MPLS, RTM_GETROUTE, mpls_getroute, mpls_dump_routes,
2485 0);
2486 rtnl_register(PF_MPLS, RTM_GETNETCONF, mpls_netconf_get_devconf,
2487 mpls_netconf_dump_devconf, 0);
2488 err = 0;
2489 out:
2490 return err;
2491
2492 out_unregister_pernet:
2493 unregister_pernet_subsys(&mpls_net_ops);
2494 goto out;
2495 }
2496 module_init(mpls_init);
2497
2498 static void __exit mpls_exit(void)
2499 {
2500 rtnl_unregister_all(PF_MPLS);
2501 rtnl_af_unregister(&mpls_af_ops);
2502 dev_remove_pack(&mpls_packet_type);
2503 unregister_netdevice_notifier(&mpls_dev_notifier);
2504 unregister_pernet_subsys(&mpls_net_ops);
2505 }
2506 module_exit(mpls_exit);
2507
2508 MODULE_DESCRIPTION("MultiProtocol Label Switching");
2509 MODULE_LICENSE("GPL v2");
2510 MODULE_ALIAS_NETPROTO(PF_MPLS);
Linux with added FPC-III support