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s390: add 'install' target to 'make help'
[linux/fpc-iii.git] / net / mpls / af_mpls.c
blobc70d750148b66759ce47525c6f6b348c2e69efaa
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/vmalloc.h>
11 #include <net/ip.h>
12 #include <net/dst.h>
13 #include <net/sock.h>
14 #include <net/arp.h>
15 #include <net/ip_fib.h>
16 #include <net/netevent.h>
17 #include <net/netns/generic.h>
18 #if IS_ENABLED(CONFIG_IPV6)
19 #include <net/ipv6.h>
20 #include <net/addrconf.h>
21 #endif
22 #include <net/nexthop.h>
23 #include "internal.h"
24
25 /* Maximum number of labels to look ahead at when selecting a path of
26 * a multipath route
27 */
28 #define MAX_MP_SELECT_LABELS 4
29
30 static int zero = 0;
31 static int label_limit = (1 << 20) - 1;
32
33 static void rtmsg_lfib(int event, u32 label, struct mpls_route *rt,
34 struct nlmsghdr *nlh, struct net *net, u32 portid,
35 unsigned int nlm_flags);
36
37 static struct mpls_route *mpls_route_input_rcu(struct net *net, unsigned index)
38 {
39 struct mpls_route *rt = NULL;
40
41 if (index < net->mpls.platform_labels) {
42 struct mpls_route __rcu **platform_label =
43 rcu_dereference(net->mpls.platform_label);
44 rt = rcu_dereference(platform_label[index]);
45 }
46 return rt;
47 }
48
49 static inline struct mpls_dev *mpls_dev_get(const struct net_device *dev)
50 {
51 return rcu_dereference_rtnl(dev->mpls_ptr);
52 }
53
54 bool mpls_output_possible(const struct net_device *dev)
55 {
56 return dev && (dev->flags & IFF_UP) && netif_carrier_ok(dev);
57 }
58 EXPORT_SYMBOL_GPL(mpls_output_possible);
59
60 static u8 *__mpls_nh_via(struct mpls_route *rt, struct mpls_nh *nh)
61 {
62 u8 *nh0_via = PTR_ALIGN((u8 *)&rt->rt_nh[rt->rt_nhn], VIA_ALEN_ALIGN);
63 int nh_index = nh - rt->rt_nh;
64
65 return nh0_via + rt->rt_max_alen * nh_index;
66 }
67
68 static const u8 *mpls_nh_via(const struct mpls_route *rt,
69 const struct mpls_nh *nh)
70 {
71 return __mpls_nh_via((struct mpls_route *)rt, (struct mpls_nh *)nh);
72 }
73
74 static unsigned int mpls_nh_header_size(const struct mpls_nh *nh)
75 {
76 /* The size of the layer 2.5 labels to be added for this route */
77 return nh->nh_labels * sizeof(struct mpls_shim_hdr);
78 }
79
80 unsigned int mpls_dev_mtu(const struct net_device *dev)
81 {
82 /* The amount of data the layer 2 frame can hold */
83 return dev->mtu;
84 }
85 EXPORT_SYMBOL_GPL(mpls_dev_mtu);
86
87 bool mpls_pkt_too_big(const struct sk_buff *skb, unsigned int mtu)
88 {
89 if (skb->len <= mtu)
90 return false;
91
92 if (skb_is_gso(skb) && skb_gso_network_seglen(skb) <= mtu)
93 return false;
94
95 return true;
96 }
97 EXPORT_SYMBOL_GPL(mpls_pkt_too_big);
98
99 static struct mpls_nh *mpls_select_multipath(struct mpls_route *rt,
100 struct sk_buff *skb, bool bos)
101 {
102 struct mpls_entry_decoded dec;
103 struct mpls_shim_hdr *hdr;
104 bool eli_seen = false;
105 int label_index;
106 int nh_index = 0;
107 u32 hash = 0;
108
109 /* No need to look further into packet if there's only
110 * one path
111 */
112 if (rt->rt_nhn == 1)
113 goto out;
114
115 for (label_index = 0; label_index < MAX_MP_SELECT_LABELS && !bos;
116 label_index++) {
117 if (!pskb_may_pull(skb, sizeof(*hdr) * label_index))
118 break;
119
120 /* Read and decode the current label */
121 hdr = mpls_hdr(skb) + label_index;
122 dec = mpls_entry_decode(hdr);
123
124 /* RFC6790 - reserved labels MUST NOT be used as keys
125 * for the load-balancing function
126 */
127 if (likely(dec.label >= MPLS_LABEL_FIRST_UNRESERVED)) {
128 hash = jhash_1word(dec.label, hash);
129
130 /* The entropy label follows the entropy label
131 * indicator, so this means that the entropy
132 * label was just added to the hash - no need to
133 * go any deeper either in the label stack or in the
134 * payload
135 */
136 if (eli_seen)
137 break;
138 } else if (dec.label == MPLS_LABEL_ENTROPY) {
139 eli_seen = true;
140 }
141
142 bos = dec.bos;
143 if (bos && pskb_may_pull(skb, sizeof(*hdr) * label_index +
144 sizeof(struct iphdr))) {
145 const struct iphdr *v4hdr;
146
147 v4hdr = (const struct iphdr *)(mpls_hdr(skb) +
148 label_index);
149 if (v4hdr->version == 4) {
150 hash = jhash_3words(ntohl(v4hdr->saddr),
151 ntohl(v4hdr->daddr),
152 v4hdr->protocol, hash);
153 } else if (v4hdr->version == 6 &&
154 pskb_may_pull(skb, sizeof(*hdr) * label_index +
155 sizeof(struct ipv6hdr))) {
156 const struct ipv6hdr *v6hdr;
157
158 v6hdr = (const struct ipv6hdr *)(mpls_hdr(skb) +
159 label_index);
160
161 hash = __ipv6_addr_jhash(&v6hdr->saddr, hash);
162 hash = __ipv6_addr_jhash(&v6hdr->daddr, hash);
163 hash = jhash_1word(v6hdr->nexthdr, hash);
164 }
165 }
166 }
167
168 nh_index = hash % rt->rt_nhn;
169 out:
170 return &rt->rt_nh[nh_index];
171 }
172
173 static bool mpls_egress(struct mpls_route *rt, struct sk_buff *skb,
174 struct mpls_entry_decoded dec)
175 {
176 enum mpls_payload_type payload_type;
177 bool success = false;
178
179 /* The IPv4 code below accesses through the IPv4 header
180 * checksum, which is 12 bytes into the packet.
181 * The IPv6 code below accesses through the IPv6 hop limit
182 * which is 8 bytes into the packet.
183 *
184 * For all supported cases there should always be at least 12
185 * bytes of packet data present. The IPv4 header is 20 bytes
186 * without options and the IPv6 header is always 40 bytes
187 * long.
188 */
189 if (!pskb_may_pull(skb, 12))
190 return false;
191
192 payload_type = rt->rt_payload_type;
193 if (payload_type == MPT_UNSPEC)
194 payload_type = ip_hdr(skb)->version;
195
196 switch (payload_type) {
197 case MPT_IPV4: {
198 struct iphdr *hdr4 = ip_hdr(skb);
199 skb->protocol = htons(ETH_P_IP);
200 csum_replace2(&hdr4->check,
201 htons(hdr4->ttl << 8),
202 htons(dec.ttl << 8));
203 hdr4->ttl = dec.ttl;
204 success = true;
205 break;
206 }
207 case MPT_IPV6: {
208 struct ipv6hdr *hdr6 = ipv6_hdr(skb);
209 skb->protocol = htons(ETH_P_IPV6);
210 hdr6->hop_limit = dec.ttl;
211 success = true;
212 break;
213 }
214 case MPT_UNSPEC:
215 break;
216 }
217
218 return success;
219 }
220
221 static int mpls_forward(struct sk_buff *skb, struct net_device *dev,
222 struct packet_type *pt, struct net_device *orig_dev)
223 {
224 struct net *net = dev_net(dev);
225 struct mpls_shim_hdr *hdr;
226 struct mpls_route *rt;
227 struct mpls_nh *nh;
228 struct mpls_entry_decoded dec;
229 struct net_device *out_dev;
230 struct mpls_dev *mdev;
231 unsigned int hh_len;
232 unsigned int new_header_size;
233 unsigned int mtu;
234 int err;
235
236 /* Careful this entire function runs inside of an rcu critical section */
237
238 mdev = mpls_dev_get(dev);
239 if (!mdev || !mdev->input_enabled)
240 goto drop;
241
242 if (skb->pkt_type != PACKET_HOST)
243 goto drop;
244
245 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
246 goto drop;
247
248 if (!pskb_may_pull(skb, sizeof(*hdr)))
249 goto drop;
250
251 /* Read and decode the label */
252 hdr = mpls_hdr(skb);
253 dec = mpls_entry_decode(hdr);
254
255 /* Pop the label */
256 skb_pull(skb, sizeof(*hdr));
257 skb_reset_network_header(skb);
258
259 skb_orphan(skb);
260
261 rt = mpls_route_input_rcu(net, dec.label);
262 if (!rt)
263 goto drop;
264
265 nh = mpls_select_multipath(rt, skb, dec.bos);
266 if (!nh)
267 goto drop;
268
269 /* Find the output device */
270 out_dev = rcu_dereference(nh->nh_dev);
271 if (!mpls_output_possible(out_dev))
272 goto drop;
273
274 if (skb_warn_if_lro(skb))
275 goto drop;
276
277 skb_forward_csum(skb);
278
279 /* Verify ttl is valid */
280 if (dec.ttl <= 1)
281 goto drop;
282 dec.ttl -= 1;
283
284 /* Verify the destination can hold the packet */
285 new_header_size = mpls_nh_header_size(nh);
286 mtu = mpls_dev_mtu(out_dev);
287 if (mpls_pkt_too_big(skb, mtu - new_header_size))
288 goto drop;
289
290 hh_len = LL_RESERVED_SPACE(out_dev);
291 if (!out_dev->header_ops)
292 hh_len = 0;
293
294 /* Ensure there is enough space for the headers in the skb */
295 if (skb_cow(skb, hh_len + new_header_size))
296 goto drop;
297
298 skb->dev = out_dev;
299 skb->protocol = htons(ETH_P_MPLS_UC);
300
301 if (unlikely(!new_header_size && dec.bos)) {
302 /* Penultimate hop popping */
303 if (!mpls_egress(rt, skb, dec))
304 goto drop;
305 } else {
306 bool bos;
307 int i;
308 skb_push(skb, new_header_size);
309 skb_reset_network_header(skb);
310 /* Push the new labels */
311 hdr = mpls_hdr(skb);
312 bos = dec.bos;
313 for (i = nh->nh_labels - 1; i >= 0; i--) {
314 hdr[i] = mpls_entry_encode(nh->nh_label[i],
315 dec.ttl, 0, bos);
316 bos = false;
317 }
318 }
319
320 err = neigh_xmit(nh->nh_via_table, out_dev, mpls_nh_via(rt, nh), skb);
321 if (err)
322 net_dbg_ratelimited("%s: packet transmission failed: %d\n",
323 __func__, err);
324 return 0;
325
326 drop:
327 kfree_skb(skb);
328 return NET_RX_DROP;
329 }
330
331 static struct packet_type mpls_packet_type __read_mostly = {
332 .type = cpu_to_be16(ETH_P_MPLS_UC),
333 .func = mpls_forward,
334 };
335
336 static const struct nla_policy rtm_mpls_policy[RTA_MAX+1] = {
337 [RTA_DST] = { .type = NLA_U32 },
338 [RTA_OIF] = { .type = NLA_U32 },
339 };
340
341 struct mpls_route_config {
342 u32 rc_protocol;
343 u32 rc_ifindex;
344 u8 rc_via_table;
345 u8 rc_via_alen;
346 u8 rc_via[MAX_VIA_ALEN];
347 u32 rc_label;
348 u8 rc_output_labels;
349 u32 rc_output_label[MAX_NEW_LABELS];
350 u32 rc_nlflags;
351 enum mpls_payload_type rc_payload_type;
352 struct nl_info rc_nlinfo;
353 struct rtnexthop *rc_mp;
354 int rc_mp_len;
355 };
356
357 static struct mpls_route *mpls_rt_alloc(int num_nh, u8 max_alen)
358 {
359 u8 max_alen_aligned = ALIGN(max_alen, VIA_ALEN_ALIGN);
360 struct mpls_route *rt;
361
362 rt = kzalloc(ALIGN(sizeof(*rt) + num_nh * sizeof(*rt->rt_nh),
363 VIA_ALEN_ALIGN) +
364 num_nh * max_alen_aligned,
365 GFP_KERNEL);
366 if (rt) {
367 rt->rt_nhn = num_nh;
368 rt->rt_max_alen = max_alen_aligned;
369 }
370
371 return rt;
372 }
373
374 static void mpls_rt_free(struct mpls_route *rt)
375 {
376 if (rt)
377 kfree_rcu(rt, rt_rcu);
378 }
379
380 static void mpls_notify_route(struct net *net, unsigned index,
381 struct mpls_route *old, struct mpls_route *new,
382 const struct nl_info *info)
383 {
384 struct nlmsghdr *nlh = info ? info->nlh : NULL;
385 unsigned portid = info ? info->portid : 0;
386 int event = new ? RTM_NEWROUTE : RTM_DELROUTE;
387 struct mpls_route *rt = new ? new : old;
388 unsigned nlm_flags = (old && new) ? NLM_F_REPLACE : 0;
389 /* Ignore reserved labels for now */
390 if (rt && (index >= MPLS_LABEL_FIRST_UNRESERVED))
391 rtmsg_lfib(event, index, rt, nlh, net, portid, nlm_flags);
392 }
393
394 static void mpls_route_update(struct net *net, unsigned index,
395 struct mpls_route *new,
396 const struct nl_info *info)
397 {
398 struct mpls_route __rcu **platform_label;
399 struct mpls_route *rt;
400
401 ASSERT_RTNL();
402
403 platform_label = rtnl_dereference(net->mpls.platform_label);
404 rt = rtnl_dereference(platform_label[index]);
405 rcu_assign_pointer(platform_label[index], new);
406
407 mpls_notify_route(net, index, rt, new, info);
408
409 /* If we removed a route free it now */
410 mpls_rt_free(rt);
411 }
412
413 static unsigned find_free_label(struct net *net)
414 {
415 struct mpls_route __rcu **platform_label;
416 size_t platform_labels;
417 unsigned index;
418
419 platform_label = rtnl_dereference(net->mpls.platform_label);
420 platform_labels = net->mpls.platform_labels;
421 for (index = MPLS_LABEL_FIRST_UNRESERVED; index < platform_labels;
422 index++) {
423 if (!rtnl_dereference(platform_label[index]))
424 return index;
425 }
426 return LABEL_NOT_SPECIFIED;
427 }
428
429 #if IS_ENABLED(CONFIG_INET)
430 static struct net_device *inet_fib_lookup_dev(struct net *net,
431 const void *addr)
432 {
433 struct net_device *dev;
434 struct rtable *rt;
435 struct in_addr daddr;
436
437 memcpy(&daddr, addr, sizeof(struct in_addr));
438 rt = ip_route_output(net, daddr.s_addr, 0, 0, 0);
439 if (IS_ERR(rt))
440 return ERR_CAST(rt);
441
442 dev = rt->dst.dev;
443 dev_hold(dev);
444
445 ip_rt_put(rt);
446
447 return dev;
448 }
449 #else
450 static struct net_device *inet_fib_lookup_dev(struct net *net,
451 const void *addr)
452 {
453 return ERR_PTR(-EAFNOSUPPORT);
454 }
455 #endif
456
457 #if IS_ENABLED(CONFIG_IPV6)
458 static struct net_device *inet6_fib_lookup_dev(struct net *net,
459 const void *addr)
460 {
461 struct net_device *dev;
462 struct dst_entry *dst;
463 struct flowi6 fl6;
464 int err;
465
466 if (!ipv6_stub)
467 return ERR_PTR(-EAFNOSUPPORT);
468
469 memset(&fl6, 0, sizeof(fl6));
470 memcpy(&fl6.daddr, addr, sizeof(struct in6_addr));
471 err = ipv6_stub->ipv6_dst_lookup(net, NULL, &dst, &fl6);
472 if (err)
473 return ERR_PTR(err);
474
475 dev = dst->dev;
476 dev_hold(dev);
477 dst_release(dst);
478
479 return dev;
480 }
481 #else
482 static struct net_device *inet6_fib_lookup_dev(struct net *net,
483 const void *addr)
484 {
485 return ERR_PTR(-EAFNOSUPPORT);
486 }
487 #endif
488
489 static struct net_device *find_outdev(struct net *net,
490 struct mpls_route *rt,
491 struct mpls_nh *nh, int oif)
492 {
493 struct net_device *dev = NULL;
494
495 if (!oif) {
496 switch (nh->nh_via_table) {
497 case NEIGH_ARP_TABLE:
498 dev = inet_fib_lookup_dev(net, mpls_nh_via(rt, nh));
499 break;
500 case NEIGH_ND_TABLE:
501 dev = inet6_fib_lookup_dev(net, mpls_nh_via(rt, nh));
502 break;
503 case NEIGH_LINK_TABLE:
504 break;
505 }
506 } else {
507 dev = dev_get_by_index(net, oif);
508 }
509
510 if (!dev)
511 return ERR_PTR(-ENODEV);
512
513 /* The caller is holding rtnl anyways, so release the dev reference */
514 dev_put(dev);
515
516 return dev;
517 }
518
519 static int mpls_nh_assign_dev(struct net *net, struct mpls_route *rt,
520 struct mpls_nh *nh, int oif)
521 {
522 struct net_device *dev = NULL;
523 int err = -ENODEV;
524
525 dev = find_outdev(net, rt, nh, oif);
526 if (IS_ERR(dev)) {
527 err = PTR_ERR(dev);
528 dev = NULL;
529 goto errout;
530 }
531
532 /* Ensure this is a supported device */
533 err = -EINVAL;
534 if (!mpls_dev_get(dev))
535 goto errout;
536
537 RCU_INIT_POINTER(nh->nh_dev, dev);
538
539 return 0;
540
541 errout:
542 return err;
543 }
544
545 static int mpls_nh_build_from_cfg(struct mpls_route_config *cfg,
546 struct mpls_route *rt)
547 {
548 struct net *net = cfg->rc_nlinfo.nl_net;
549 struct mpls_nh *nh = rt->rt_nh;
550 int err;
551 int i;
552
553 if (!nh)
554 return -ENOMEM;
555
556 err = -EINVAL;
557 /* Ensure only a supported number of labels are present */
558 if (cfg->rc_output_labels > MAX_NEW_LABELS)
559 goto errout;
560
561 nh->nh_labels = cfg->rc_output_labels;
562 for (i = 0; i < nh->nh_labels; i++)
563 nh->nh_label[i] = cfg->rc_output_label[i];
564
565 nh->nh_via_table = cfg->rc_via_table;
566 memcpy(__mpls_nh_via(rt, nh), cfg->rc_via, cfg->rc_via_alen);
567 nh->nh_via_alen = cfg->rc_via_alen;
568
569 err = mpls_nh_assign_dev(net, rt, nh, cfg->rc_ifindex);
570 if (err)
571 goto errout;
572
573 return 0;
574
575 errout:
576 return err;
577 }
578
579 static int mpls_nh_build(struct net *net, struct mpls_route *rt,
580 struct mpls_nh *nh, int oif,
581 struct nlattr *via, struct nlattr *newdst)
582 {
583 int err = -ENOMEM;
584
585 if (!nh)
586 goto errout;
587
588 if (newdst) {
589 err = nla_get_labels(newdst, MAX_NEW_LABELS,
590 &nh->nh_labels, nh->nh_label);
591 if (err)
592 goto errout;
593 }
594
595 err = nla_get_via(via, &nh->nh_via_alen, &nh->nh_via_table,
596 __mpls_nh_via(rt, nh));
597 if (err)
598 goto errout;
599
600 err = mpls_nh_assign_dev(net, rt, nh, oif);
601 if (err)
602 goto errout;
603
604 return 0;
605
606 errout:
607 return err;
608 }
609
610 static int mpls_count_nexthops(struct rtnexthop *rtnh, int len,
611 u8 cfg_via_alen, u8 *max_via_alen)
612 {
613 int nhs = 0;
614 int remaining = len;
615
616 if (!rtnh) {
617 *max_via_alen = cfg_via_alen;
618 return 1;
619 }
620
621 *max_via_alen = 0;
622
623 while (rtnh_ok(rtnh, remaining)) {
624 struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
625 int attrlen;
626
627 attrlen = rtnh_attrlen(rtnh);
628 nla = nla_find(attrs, attrlen, RTA_VIA);
629 if (nla && nla_len(nla) >=
630 offsetof(struct rtvia, rtvia_addr)) {
631 int via_alen = nla_len(nla) -
632 offsetof(struct rtvia, rtvia_addr);
633
634 if (via_alen <= MAX_VIA_ALEN)
635 *max_via_alen = max_t(u16, *max_via_alen,
636 via_alen);
637 }
638
639 nhs++;
640 rtnh = rtnh_next(rtnh, &remaining);
641 }
642
643 /* leftover implies invalid nexthop configuration, discard it */
644 return remaining > 0 ? 0 : nhs;
645 }
646
647 static int mpls_nh_build_multi(struct mpls_route_config *cfg,
648 struct mpls_route *rt)
649 {
650 struct rtnexthop *rtnh = cfg->rc_mp;
651 struct nlattr *nla_via, *nla_newdst;
652 int remaining = cfg->rc_mp_len;
653 int nhs = 0;
654 int err = 0;
655
656 change_nexthops(rt) {
657 int attrlen;
658
659 nla_via = NULL;
660 nla_newdst = NULL;
661
662 err = -EINVAL;
663 if (!rtnh_ok(rtnh, remaining))
664 goto errout;
665
666 /* neither weighted multipath nor any flags
667 * are supported
668 */
669 if (rtnh->rtnh_hops || rtnh->rtnh_flags)
670 goto errout;
671
672 attrlen = rtnh_attrlen(rtnh);
673 if (attrlen > 0) {
674 struct nlattr *attrs = rtnh_attrs(rtnh);
675
676 nla_via = nla_find(attrs, attrlen, RTA_VIA);
677 nla_newdst = nla_find(attrs, attrlen, RTA_NEWDST);
678 }
679
680 if (!nla_via)
681 goto errout;
682
683 err = mpls_nh_build(cfg->rc_nlinfo.nl_net, rt, nh,
684 rtnh->rtnh_ifindex, nla_via,
685 nla_newdst);
686 if (err)
687 goto errout;
688
689 rtnh = rtnh_next(rtnh, &remaining);
690 nhs++;
691 } endfor_nexthops(rt);
692
693 rt->rt_nhn = nhs;
694
695 return 0;
696
697 errout:
698 return err;
699 }
700
701 static int mpls_route_add(struct mpls_route_config *cfg)
702 {
703 struct mpls_route __rcu **platform_label;
704 struct net *net = cfg->rc_nlinfo.nl_net;
705 struct mpls_route *rt, *old;
706 int err = -EINVAL;
707 u8 max_via_alen;
708 unsigned index;
709 int nhs;
710
711 index = cfg->rc_label;
712
713 /* If a label was not specified during insert pick one */
714 if ((index == LABEL_NOT_SPECIFIED) &&
715 (cfg->rc_nlflags & NLM_F_CREATE)) {
716 index = find_free_label(net);
717 }
718
719 /* Reserved labels may not be set */
720 if (index < MPLS_LABEL_FIRST_UNRESERVED)
721 goto errout;
722
723 /* The full 20 bit range may not be supported. */
724 if (index >= net->mpls.platform_labels)
725 goto errout;
726
727 /* Append makes no sense with mpls */
728 err = -EOPNOTSUPP;
729 if (cfg->rc_nlflags & NLM_F_APPEND)
730 goto errout;
731
732 err = -EEXIST;
733 platform_label = rtnl_dereference(net->mpls.platform_label);
734 old = rtnl_dereference(platform_label[index]);
735 if ((cfg->rc_nlflags & NLM_F_EXCL) && old)
736 goto errout;
737
738 err = -EEXIST;
739 if (!(cfg->rc_nlflags & NLM_F_REPLACE) && old)
740 goto errout;
741
742 err = -ENOENT;
743 if (!(cfg->rc_nlflags & NLM_F_CREATE) && !old)
744 goto errout;
745
746 err = -EINVAL;
747 nhs = mpls_count_nexthops(cfg->rc_mp, cfg->rc_mp_len,
748 cfg->rc_via_alen, &max_via_alen);
749 if (nhs == 0)
750 goto errout;
751
752 err = -ENOMEM;
753 rt = mpls_rt_alloc(nhs, max_via_alen);
754 if (!rt)
755 goto errout;
756
757 rt->rt_protocol = cfg->rc_protocol;
758 rt->rt_payload_type = cfg->rc_payload_type;
759
760 if (cfg->rc_mp)
761 err = mpls_nh_build_multi(cfg, rt);
762 else
763 err = mpls_nh_build_from_cfg(cfg, rt);
764 if (err)
765 goto freert;
766
767 mpls_route_update(net, index, rt, &cfg->rc_nlinfo);
768
769 return 0;
770
771 freert:
772 mpls_rt_free(rt);
773 errout:
774 return err;
775 }
776
777 static int mpls_route_del(struct mpls_route_config *cfg)
778 {
779 struct net *net = cfg->rc_nlinfo.nl_net;
780 unsigned index;
781 int err = -EINVAL;
782
783 index = cfg->rc_label;
784
785 /* Reserved labels may not be removed */
786 if (index < MPLS_LABEL_FIRST_UNRESERVED)
787 goto errout;
788
789 /* The full 20 bit range may not be supported */
790 if (index >= net->mpls.platform_labels)
791 goto errout;
792
793 mpls_route_update(net, index, NULL, &cfg->rc_nlinfo);
794
795 err = 0;
796 errout:
797 return err;
798 }
799
800 #define MPLS_PERDEV_SYSCTL_OFFSET(field) \
801 (&((struct mpls_dev *)0)->field)
802
803 static const struct ctl_table mpls_dev_table[] = {
804 {
805 .procname = "input",
806 .maxlen = sizeof(int),
807 .mode = 0644,
808 .proc_handler = proc_dointvec,
809 .data = MPLS_PERDEV_SYSCTL_OFFSET(input_enabled),
810 },
811 { }
812 };
813
814 static int mpls_dev_sysctl_register(struct net_device *dev,
815 struct mpls_dev *mdev)
816 {
817 char path[sizeof("net/mpls/conf/") + IFNAMSIZ];
818 struct ctl_table *table;
819 int i;
820
821 table = kmemdup(&mpls_dev_table, sizeof(mpls_dev_table), GFP_KERNEL);
822 if (!table)
823 goto out;
824
825 /* Table data contains only offsets relative to the base of
826 * the mdev at this point, so make them absolute.
827 */
828 for (i = 0; i < ARRAY_SIZE(mpls_dev_table); i++)
829 table[i].data = (char *)mdev + (uintptr_t)table[i].data;
830
831 snprintf(path, sizeof(path), "net/mpls/conf/%s", dev->name);
832
833 mdev->sysctl = register_net_sysctl(dev_net(dev), path, table);
834 if (!mdev->sysctl)
835 goto free;
836
837 return 0;
838
839 free:
840 kfree(table);
841 out:
842 return -ENOBUFS;
843 }
844
845 static void mpls_dev_sysctl_unregister(struct mpls_dev *mdev)
846 {
847 struct ctl_table *table;
848
849 table = mdev->sysctl->ctl_table_arg;
850 unregister_net_sysctl_table(mdev->sysctl);
851 kfree(table);
852 }
853
854 static struct mpls_dev *mpls_add_dev(struct net_device *dev)
855 {
856 struct mpls_dev *mdev;
857 int err = -ENOMEM;
858
859 ASSERT_RTNL();
860
861 mdev = kzalloc(sizeof(*mdev), GFP_KERNEL);
862 if (!mdev)
863 return ERR_PTR(err);
864
865 err = mpls_dev_sysctl_register(dev, mdev);
866 if (err)
867 goto free;
868
869 rcu_assign_pointer(dev->mpls_ptr, mdev);
870
871 return mdev;
872
873 free:
874 kfree(mdev);
875 return ERR_PTR(err);
876 }
877
878 static void mpls_ifdown(struct net_device *dev)
879 {
880 struct mpls_route __rcu **platform_label;
881 struct net *net = dev_net(dev);
882 struct mpls_dev *mdev;
883 unsigned index;
884
885 platform_label = rtnl_dereference(net->mpls.platform_label);
886 for (index = 0; index < net->mpls.platform_labels; index++) {
887 struct mpls_route *rt = rtnl_dereference(platform_label[index]);
888 if (!rt)
889 continue;
890 for_nexthops(rt) {
891 if (rtnl_dereference(nh->nh_dev) != dev)
892 continue;
893 nh->nh_dev = NULL;
894 } endfor_nexthops(rt);
895 }
896
897 mdev = mpls_dev_get(dev);
898 if (!mdev)
899 return;
900
901 mpls_dev_sysctl_unregister(mdev);
902
903 RCU_INIT_POINTER(dev->mpls_ptr, NULL);
904
905 kfree_rcu(mdev, rcu);
906 }
907
908 static int mpls_dev_notify(struct notifier_block *this, unsigned long event,
909 void *ptr)
910 {
911 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
912 struct mpls_dev *mdev;
913
914 switch(event) {
915 case NETDEV_REGISTER:
916 /* For now just support ethernet devices */
917 if ((dev->type == ARPHRD_ETHER) ||
918 (dev->type == ARPHRD_LOOPBACK)) {
919 mdev = mpls_add_dev(dev);
920 if (IS_ERR(mdev))
921 return notifier_from_errno(PTR_ERR(mdev));
922 }
923 break;
924
925 case NETDEV_UNREGISTER:
926 mpls_ifdown(dev);
927 break;
928 case NETDEV_CHANGENAME:
929 mdev = mpls_dev_get(dev);
930 if (mdev) {
931 int err;
932
933 mpls_dev_sysctl_unregister(mdev);
934 err = mpls_dev_sysctl_register(dev, mdev);
935 if (err)
936 return notifier_from_errno(err);
937 }
938 break;
939 }
940 return NOTIFY_OK;
941 }
942
943 static struct notifier_block mpls_dev_notifier = {
944 .notifier_call = mpls_dev_notify,
945 };
946
947 static int nla_put_via(struct sk_buff *skb,
948 u8 table, const void *addr, int alen)
949 {
950 static const int table_to_family[NEIGH_NR_TABLES + 1] = {
951 AF_INET, AF_INET6, AF_DECnet, AF_PACKET,
952 };
953 struct nlattr *nla;
954 struct rtvia *via;
955 int family = AF_UNSPEC;
956
957 nla = nla_reserve(skb, RTA_VIA, alen + 2);
958 if (!nla)
959 return -EMSGSIZE;
960
961 if (table <= NEIGH_NR_TABLES)
962 family = table_to_family[table];
963
964 via = nla_data(nla);
965 via->rtvia_family = family;
966 memcpy(via->rtvia_addr, addr, alen);
967 return 0;
968 }
969
970 int nla_put_labels(struct sk_buff *skb, int attrtype,
971 u8 labels, const u32 label[])
972 {
973 struct nlattr *nla;
974 struct mpls_shim_hdr *nla_label;
975 bool bos;
976 int i;
977 nla = nla_reserve(skb, attrtype, labels*4);
978 if (!nla)
979 return -EMSGSIZE;
980
981 nla_label = nla_data(nla);
982 bos = true;
983 for (i = labels - 1; i >= 0; i--) {
984 nla_label[i] = mpls_entry_encode(label[i], 0, 0, bos);
985 bos = false;
986 }
987
988 return 0;
989 }
990 EXPORT_SYMBOL_GPL(nla_put_labels);
991
992 int nla_get_labels(const struct nlattr *nla,
993 u32 max_labels, u8 *labels, u32 label[])
994 {
995 unsigned len = nla_len(nla);
996 unsigned nla_labels;
997 struct mpls_shim_hdr *nla_label;
998 bool bos;
999 int i;
1000
1001 /* len needs to be an even multiple of 4 (the label size) */
1002 if (len & 3)
1003 return -EINVAL;
1004
1005 /* Limit the number of new labels allowed */
1006 nla_labels = len/4;
1007 if (nla_labels > max_labels)
1008 return -EINVAL;
1009
1010 nla_label = nla_data(nla);
1011 bos = true;
1012 for (i = nla_labels - 1; i >= 0; i--, bos = false) {
1013 struct mpls_entry_decoded dec;
1014 dec = mpls_entry_decode(nla_label + i);
1015
1016 /* Ensure the bottom of stack flag is properly set
1017 * and ttl and tc are both clear.
1018 */
1019 if ((dec.bos != bos) || dec.ttl || dec.tc)
1020 return -EINVAL;
1021
1022 switch (dec.label) {
1023 case MPLS_LABEL_IMPLNULL:
1024 /* RFC3032: This is a label that an LSR may
1025 * assign and distribute, but which never
1026 * actually appears in the encapsulation.
1027 */
1028 return -EINVAL;
1029 }
1030
1031 label[i] = dec.label;
1032 }
1033 *labels = nla_labels;
1034 return 0;
1035 }
1036 EXPORT_SYMBOL_GPL(nla_get_labels);
1037
1038 int nla_get_via(const struct nlattr *nla, u8 *via_alen,
1039 u8 *via_table, u8 via_addr[])
1040 {
1041 struct rtvia *via = nla_data(nla);
1042 int err = -EINVAL;
1043 int alen;
1044
1045 if (nla_len(nla) < offsetof(struct rtvia, rtvia_addr))
1046 goto errout;
1047 alen = nla_len(nla) -
1048 offsetof(struct rtvia, rtvia_addr);
1049 if (alen > MAX_VIA_ALEN)
1050 goto errout;
1051
1052 /* Validate the address family */
1053 switch (via->rtvia_family) {
1054 case AF_PACKET:
1055 *via_table = NEIGH_LINK_TABLE;
1056 break;
1057 case AF_INET:
1058 *via_table = NEIGH_ARP_TABLE;
1059 if (alen != 4)
1060 goto errout;
1061 break;
1062 case AF_INET6:
1063 *via_table = NEIGH_ND_TABLE;
1064 if (alen != 16)
1065 goto errout;
1066 break;
1067 default:
1068 /* Unsupported address family */
1069 goto errout;
1070 }
1071
1072 memcpy(via_addr, via->rtvia_addr, alen);
1073 *via_alen = alen;
1074 err = 0;
1075
1076 errout:
1077 return err;
1078 }
1079
1080 static int rtm_to_route_config(struct sk_buff *skb, struct nlmsghdr *nlh,
1081 struct mpls_route_config *cfg)
1082 {
1083 struct rtmsg *rtm;
1084 struct nlattr *tb[RTA_MAX+1];
1085 int index;
1086 int err;
1087
1088 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_mpls_policy);
1089 if (err < 0)
1090 goto errout;
1091
1092 err = -EINVAL;
1093 rtm = nlmsg_data(nlh);
1094 memset(cfg, 0, sizeof(*cfg));
1095
1096 if (rtm->rtm_family != AF_MPLS)
1097 goto errout;
1098 if (rtm->rtm_dst_len != 20)
1099 goto errout;
1100 if (rtm->rtm_src_len != 0)
1101 goto errout;
1102 if (rtm->rtm_tos != 0)
1103 goto errout;
1104 if (rtm->rtm_table != RT_TABLE_MAIN)
1105 goto errout;
1106 /* Any value is acceptable for rtm_protocol */
1107
1108 /* As mpls uses destination specific addresses
1109 * (or source specific address in the case of multicast)
1110 * all addresses have universal scope.
1111 */
1112 if (rtm->rtm_scope != RT_SCOPE_UNIVERSE)
1113 goto errout;
1114 if (rtm->rtm_type != RTN_UNICAST)
1115 goto errout;
1116 if (rtm->rtm_flags != 0)
1117 goto errout;
1118
1119 cfg->rc_label = LABEL_NOT_SPECIFIED;
1120 cfg->rc_protocol = rtm->rtm_protocol;
1121 cfg->rc_nlflags = nlh->nlmsg_flags;
1122 cfg->rc_nlinfo.portid = NETLINK_CB(skb).portid;
1123 cfg->rc_nlinfo.nlh = nlh;
1124 cfg->rc_nlinfo.nl_net = sock_net(skb->sk);
1125
1126 for (index = 0; index <= RTA_MAX; index++) {
1127 struct nlattr *nla = tb[index];
1128 if (!nla)
1129 continue;
1130
1131 switch(index) {
1132 case RTA_OIF:
1133 cfg->rc_ifindex = nla_get_u32(nla);
1134 break;
1135 case RTA_NEWDST:
1136 if (nla_get_labels(nla, MAX_NEW_LABELS,
1137 &cfg->rc_output_labels,
1138 cfg->rc_output_label))
1139 goto errout;
1140 break;
1141 case RTA_DST:
1142 {
1143 u8 label_count;
1144 if (nla_get_labels(nla, 1, &label_count,
1145 &cfg->rc_label))
1146 goto errout;
1147
1148 /* Reserved labels may not be set */
1149 if (cfg->rc_label < MPLS_LABEL_FIRST_UNRESERVED)
1150 goto errout;
1151
1152 break;
1153 }
1154 case RTA_VIA:
1155 {
1156 if (nla_get_via(nla, &cfg->rc_via_alen,
1157 &cfg->rc_via_table, cfg->rc_via))
1158 goto errout;
1159 break;
1160 }
1161 case RTA_MULTIPATH:
1162 {
1163 cfg->rc_mp = nla_data(nla);
1164 cfg->rc_mp_len = nla_len(nla);
1165 break;
1166 }
1167 default:
1168 /* Unsupported attribute */
1169 goto errout;
1170 }
1171 }
1172
1173 err = 0;
1174 errout:
1175 return err;
1176 }
1177
1178 static int mpls_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh)
1179 {
1180 struct mpls_route_config cfg;
1181 int err;
1182
1183 err = rtm_to_route_config(skb, nlh, &cfg);
1184 if (err < 0)
1185 return err;
1186
1187 return mpls_route_del(&cfg);
1188 }
1189
1190
1191 static int mpls_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh)
1192 {
1193 struct mpls_route_config cfg;
1194 int err;
1195
1196 err = rtm_to_route_config(skb, nlh, &cfg);
1197 if (err < 0)
1198 return err;
1199
1200 return mpls_route_add(&cfg);
1201 }
1202
1203 static int mpls_dump_route(struct sk_buff *skb, u32 portid, u32 seq, int event,
1204 u32 label, struct mpls_route *rt, int flags)
1205 {
1206 struct net_device *dev;
1207 struct nlmsghdr *nlh;
1208 struct rtmsg *rtm;
1209
1210 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*rtm), flags);
1211 if (nlh == NULL)
1212 return -EMSGSIZE;
1213
1214 rtm = nlmsg_data(nlh);
1215 rtm->rtm_family = AF_MPLS;
1216 rtm->rtm_dst_len = 20;
1217 rtm->rtm_src_len = 0;
1218 rtm->rtm_tos = 0;
1219 rtm->rtm_table = RT_TABLE_MAIN;
1220 rtm->rtm_protocol = rt->rt_protocol;
1221 rtm->rtm_scope = RT_SCOPE_UNIVERSE;
1222 rtm->rtm_type = RTN_UNICAST;
1223 rtm->rtm_flags = 0;
1224
1225 if (nla_put_labels(skb, RTA_DST, 1, &label))
1226 goto nla_put_failure;
1227 if (rt->rt_nhn == 1) {
1228 const struct mpls_nh *nh = rt->rt_nh;
1229
1230 if (nh->nh_labels &&
1231 nla_put_labels(skb, RTA_NEWDST, nh->nh_labels,
1232 nh->nh_label))
1233 goto nla_put_failure;
1234 if (nla_put_via(skb, nh->nh_via_table, mpls_nh_via(rt, nh),
1235 nh->nh_via_alen))
1236 goto nla_put_failure;
1237 dev = rtnl_dereference(nh->nh_dev);
1238 if (dev && nla_put_u32(skb, RTA_OIF, dev->ifindex))
1239 goto nla_put_failure;
1240 } else {
1241 struct rtnexthop *rtnh;
1242 struct nlattr *mp;
1243
1244 mp = nla_nest_start(skb, RTA_MULTIPATH);
1245 if (!mp)
1246 goto nla_put_failure;
1247
1248 for_nexthops(rt) {
1249 rtnh = nla_reserve_nohdr(skb, sizeof(*rtnh));
1250 if (!rtnh)
1251 goto nla_put_failure;
1252
1253 dev = rtnl_dereference(nh->nh_dev);
1254 if (dev)
1255 rtnh->rtnh_ifindex = dev->ifindex;
1256 if (nh->nh_labels && nla_put_labels(skb, RTA_NEWDST,
1257 nh->nh_labels,
1258 nh->nh_label))
1259 goto nla_put_failure;
1260 if (nla_put_via(skb, nh->nh_via_table,
1261 mpls_nh_via(rt, nh),
1262 nh->nh_via_alen))
1263 goto nla_put_failure;
1264
1265 /* length of rtnetlink header + attributes */
1266 rtnh->rtnh_len = nlmsg_get_pos(skb) - (void *)rtnh;
1267 } endfor_nexthops(rt);
1268
1269 nla_nest_end(skb, mp);
1270 }
1271
1272 nlmsg_end(skb, nlh);
1273 return 0;
1274
1275 nla_put_failure:
1276 nlmsg_cancel(skb, nlh);
1277 return -EMSGSIZE;
1278 }
1279
1280 static int mpls_dump_routes(struct sk_buff *skb, struct netlink_callback *cb)
1281 {
1282 struct net *net = sock_net(skb->sk);
1283 struct mpls_route __rcu **platform_label;
1284 size_t platform_labels;
1285 unsigned int index;
1286
1287 ASSERT_RTNL();
1288
1289 index = cb->args[0];
1290 if (index < MPLS_LABEL_FIRST_UNRESERVED)
1291 index = MPLS_LABEL_FIRST_UNRESERVED;
1292
1293 platform_label = rtnl_dereference(net->mpls.platform_label);
1294 platform_labels = net->mpls.platform_labels;
1295 for (; index < platform_labels; index++) {
1296 struct mpls_route *rt;
1297 rt = rtnl_dereference(platform_label[index]);
1298 if (!rt)
1299 continue;
1300
1301 if (mpls_dump_route(skb, NETLINK_CB(cb->skb).portid,
1302 cb->nlh->nlmsg_seq, RTM_NEWROUTE,
1303 index, rt, NLM_F_MULTI) < 0)
1304 break;
1305 }
1306 cb->args[0] = index;
1307
1308 return skb->len;
1309 }
1310
1311 static inline size_t lfib_nlmsg_size(struct mpls_route *rt)
1312 {
1313 size_t payload =
1314 NLMSG_ALIGN(sizeof(struct rtmsg))
1315 + nla_total_size(4); /* RTA_DST */
1316
1317 if (rt->rt_nhn == 1) {
1318 struct mpls_nh *nh = rt->rt_nh;
1319
1320 if (nh->nh_dev)
1321 payload += nla_total_size(4); /* RTA_OIF */
1322 payload += nla_total_size(2 + nh->nh_via_alen); /* RTA_VIA */
1323 if (nh->nh_labels) /* RTA_NEWDST */
1324 payload += nla_total_size(nh->nh_labels * 4);
1325 } else {
1326 /* each nexthop is packed in an attribute */
1327 size_t nhsize = 0;
1328
1329 for_nexthops(rt) {
1330 nhsize += nla_total_size(sizeof(struct rtnexthop));
1331 nhsize += nla_total_size(2 + nh->nh_via_alen);
1332 if (nh->nh_labels)
1333 nhsize += nla_total_size(nh->nh_labels * 4);
1334 } endfor_nexthops(rt);
1335 /* nested attribute */
1336 payload += nla_total_size(nhsize);
1337 }
1338
1339 return payload;
1340 }
1341
1342 static void rtmsg_lfib(int event, u32 label, struct mpls_route *rt,
1343 struct nlmsghdr *nlh, struct net *net, u32 portid,
1344 unsigned int nlm_flags)
1345 {
1346 struct sk_buff *skb;
1347 u32 seq = nlh ? nlh->nlmsg_seq : 0;
1348 int err = -ENOBUFS;
1349
1350 skb = nlmsg_new(lfib_nlmsg_size(rt), GFP_KERNEL);
1351 if (skb == NULL)
1352 goto errout;
1353
1354 err = mpls_dump_route(skb, portid, seq, event, label, rt, nlm_flags);
1355 if (err < 0) {
1356 /* -EMSGSIZE implies BUG in lfib_nlmsg_size */
1357 WARN_ON(err == -EMSGSIZE);
1358 kfree_skb(skb);
1359 goto errout;
1360 }
1361 rtnl_notify(skb, net, portid, RTNLGRP_MPLS_ROUTE, nlh, GFP_KERNEL);
1362
1363 return;
1364 errout:
1365 if (err < 0)
1366 rtnl_set_sk_err(net, RTNLGRP_MPLS_ROUTE, err);
1367 }
1368
1369 static int resize_platform_label_table(struct net *net, size_t limit)
1370 {
1371 size_t size = sizeof(struct mpls_route *) * limit;
1372 size_t old_limit;
1373 size_t cp_size;
1374 struct mpls_route __rcu **labels = NULL, **old;
1375 struct mpls_route *rt0 = NULL, *rt2 = NULL;
1376 unsigned index;
1377
1378 if (size) {
1379 labels = kzalloc(size, GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY);
1380 if (!labels)
1381 labels = vzalloc(size);
1382
1383 if (!labels)
1384 goto nolabels;
1385 }
1386
1387 /* In case the predefined labels need to be populated */
1388 if (limit > MPLS_LABEL_IPV4NULL) {
1389 struct net_device *lo = net->loopback_dev;
1390 rt0 = mpls_rt_alloc(1, lo->addr_len);
1391 if (!rt0)
1392 goto nort0;
1393 RCU_INIT_POINTER(rt0->rt_nh->nh_dev, lo);
1394 rt0->rt_protocol = RTPROT_KERNEL;
1395 rt0->rt_payload_type = MPT_IPV4;
1396 rt0->rt_nh->nh_via_table = NEIGH_LINK_TABLE;
1397 rt0->rt_nh->nh_via_alen = lo->addr_len;
1398 memcpy(__mpls_nh_via(rt0, rt0->rt_nh), lo->dev_addr,
1399 lo->addr_len);
1400 }
1401 if (limit > MPLS_LABEL_IPV6NULL) {
1402 struct net_device *lo = net->loopback_dev;
1403 rt2 = mpls_rt_alloc(1, lo->addr_len);
1404 if (!rt2)
1405 goto nort2;
1406 RCU_INIT_POINTER(rt2->rt_nh->nh_dev, lo);
1407 rt2->rt_protocol = RTPROT_KERNEL;
1408 rt2->rt_payload_type = MPT_IPV6;
1409 rt2->rt_nh->nh_via_table = NEIGH_LINK_TABLE;
1410 rt2->rt_nh->nh_via_alen = lo->addr_len;
1411 memcpy(__mpls_nh_via(rt2, rt2->rt_nh), lo->dev_addr,
1412 lo->addr_len);
1413 }
1414
1415 rtnl_lock();
1416 /* Remember the original table */
1417 old = rtnl_dereference(net->mpls.platform_label);
1418 old_limit = net->mpls.platform_labels;
1419
1420 /* Free any labels beyond the new table */
1421 for (index = limit; index < old_limit; index++)
1422 mpls_route_update(net, index, NULL, NULL);
1423
1424 /* Copy over the old labels */
1425 cp_size = size;
1426 if (old_limit < limit)
1427 cp_size = old_limit * sizeof(struct mpls_route *);
1428
1429 memcpy(labels, old, cp_size);
1430
1431 /* If needed set the predefined labels */
1432 if ((old_limit <= MPLS_LABEL_IPV6NULL) &&
1433 (limit > MPLS_LABEL_IPV6NULL)) {
1434 RCU_INIT_POINTER(labels[MPLS_LABEL_IPV6NULL], rt2);
1435 rt2 = NULL;
1436 }
1437
1438 if ((old_limit <= MPLS_LABEL_IPV4NULL) &&
1439 (limit > MPLS_LABEL_IPV4NULL)) {
1440 RCU_INIT_POINTER(labels[MPLS_LABEL_IPV4NULL], rt0);
1441 rt0 = NULL;
1442 }
1443
1444 /* Update the global pointers */
1445 net->mpls.platform_labels = limit;
1446 rcu_assign_pointer(net->mpls.platform_label, labels);
1447
1448 rtnl_unlock();
1449
1450 mpls_rt_free(rt2);
1451 mpls_rt_free(rt0);
1452
1453 if (old) {
1454 synchronize_rcu();
1455 kvfree(old);
1456 }
1457 return 0;
1458
1459 nort2:
1460 mpls_rt_free(rt0);
1461 nort0:
1462 kvfree(labels);
1463 nolabels:
1464 return -ENOMEM;
1465 }
1466
1467 static int mpls_platform_labels(struct ctl_table *table, int write,
1468 void __user *buffer, size_t *lenp, loff_t *ppos)
1469 {
1470 struct net *net = table->data;
1471 int platform_labels = net->mpls.platform_labels;
1472 int ret;
1473 struct ctl_table tmp = {
1474 .procname = table->procname,
1475 .data = &platform_labels,
1476 .maxlen = sizeof(int),
1477 .mode = table->mode,
1478 .extra1 = &zero,
1479 .extra2 = &label_limit,
1480 };
1481
1482 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
1483
1484 if (write && ret == 0)
1485 ret = resize_platform_label_table(net, platform_labels);
1486
1487 return ret;
1488 }
1489
1490 static const struct ctl_table mpls_table[] = {
1491 {
1492 .procname = "platform_labels",
1493 .data = NULL,
1494 .maxlen = sizeof(int),
1495 .mode = 0644,
1496 .proc_handler = mpls_platform_labels,
1497 },
1498 { }
1499 };
1500
1501 static int mpls_net_init(struct net *net)
1502 {
1503 struct ctl_table *table;
1504
1505 net->mpls.platform_labels = 0;
1506 net->mpls.platform_label = NULL;
1507
1508 table = kmemdup(mpls_table, sizeof(mpls_table), GFP_KERNEL);
1509 if (table == NULL)
1510 return -ENOMEM;
1511
1512 table[0].data = net;
1513 net->mpls.ctl = register_net_sysctl(net, "net/mpls", table);
1514 if (net->mpls.ctl == NULL) {
1515 kfree(table);
1516 return -ENOMEM;
1517 }
1518
1519 return 0;
1520 }
1521
1522 static void mpls_net_exit(struct net *net)
1523 {
1524 struct mpls_route __rcu **platform_label;
1525 size_t platform_labels;
1526 struct ctl_table *table;
1527 unsigned int index;
1528
1529 table = net->mpls.ctl->ctl_table_arg;
1530 unregister_net_sysctl_table(net->mpls.ctl);
1531 kfree(table);
1532
1533 /* An rcu grace period has passed since there was a device in
1534 * the network namespace (and thus the last in flight packet)
1535 * left this network namespace. This is because
1536 * unregister_netdevice_many and netdev_run_todo has completed
1537 * for each network device that was in this network namespace.
1538 *
1539 * As such no additional rcu synchronization is necessary when
1540 * freeing the platform_label table.
1541 */
1542 rtnl_lock();
1543 platform_label = rtnl_dereference(net->mpls.platform_label);
1544 platform_labels = net->mpls.platform_labels;
1545 for (index = 0; index < platform_labels; index++) {
1546 struct mpls_route *rt = rtnl_dereference(platform_label[index]);
1547 RCU_INIT_POINTER(platform_label[index], NULL);
1548 mpls_rt_free(rt);
1549 }
1550 rtnl_unlock();
1551
1552 kvfree(platform_label);
1553 }
1554
1555 static struct pernet_operations mpls_net_ops = {
1556 .init = mpls_net_init,
1557 .exit = mpls_net_exit,
1558 };
1559
1560 static int __init mpls_init(void)
1561 {
1562 int err;
1563
1564 BUILD_BUG_ON(sizeof(struct mpls_shim_hdr) != 4);
1565
1566 err = register_pernet_subsys(&mpls_net_ops);
1567 if (err)
1568 goto out;
1569
1570 err = register_netdevice_notifier(&mpls_dev_notifier);
1571 if (err)
1572 goto out_unregister_pernet;
1573
1574 dev_add_pack(&mpls_packet_type);
1575
1576 rtnl_register(PF_MPLS, RTM_NEWROUTE, mpls_rtm_newroute, NULL, NULL);
1577 rtnl_register(PF_MPLS, RTM_DELROUTE, mpls_rtm_delroute, NULL, NULL);
1578 rtnl_register(PF_MPLS, RTM_GETROUTE, NULL, mpls_dump_routes, NULL);
1579 err = 0;
1580 out:
1581 return err;
1582
1583 out_unregister_pernet:
1584 unregister_pernet_subsys(&mpls_net_ops);
1585 goto out;
1586 }
1587 module_init(mpls_init);
1588
1589 static void __exit mpls_exit(void)
1590 {
1591 rtnl_unregister_all(PF_MPLS);
1592 dev_remove_pack(&mpls_packet_type);
1593 unregister_netdevice_notifier(&mpls_dev_notifier);
1594 unregister_pernet_subsys(&mpls_net_ops);
1595 }
1596 module_exit(mpls_exit);
1597
1598 MODULE_DESCRIPTION("MultiProtocol Label Switching");
1599 MODULE_LICENSE("GPL v2");
1600 MODULE_ALIAS_NETPROTO(PF_MPLS);
Linux with added FPC-III support