1 // SPDX-License-Identifier: GPL-2.0-only 2 #include <linux/types.h> 3 #include <linux/skbuff.h> 4 #include <linux/socket.h> 5 #include <linux/sysctl.h> 6 #include <linux/net.h> 7 #include <linux/module.h> 8 #include <linux/if_arp.h> 9 #include <linux/ipv6.h> 10 #include <linux/mpls.h> 11 #include <linux/netconf.h> 12 #include <linux/nospec.h> 13 #include <linux/vmalloc.h> 14 #include <linux/percpu.h> 15 #include <net/gso.h> 16 #include <net/ip.h> 17 #include <net/dst.h> 18 #include <net/sock.h> 19 #include <net/arp.h> 20 #include <net/ip_fib.h> 21 #include <net/netevent.h> 22 #include <net/ip_tunnels.h> 23 #include <net/netns/generic.h> 24 #if IS_ENABLED(CONFIG_IPV6) 25 #include <net/ipv6.h> 26 #endif 27 #include <net/rtnh.h> 28 #include "internal.h" 29 30 /* max memory we will use for mpls_route */ 31 #define MAX_MPLS_ROUTE_MEM 4096 32 33 /* Maximum number of labels to look ahead at when selecting a path of 34 * a multipath route 35 */ 36 #define MAX_MP_SELECT_LABELS 4 37 38 #define MPLS_NEIGH_TABLE_UNSPEC (NEIGH_LINK_TABLE + 1) 39 40 static int label_limit = (1 << 20) - 1; 41 static int ttl_max = 255; 42 43 #if IS_ENABLED(CONFIG_NET_IP_TUNNEL) 44 static size_t ipgre_mpls_encap_hlen(struct ip_tunnel_encap *e) 45 { 46 return sizeof(struct mpls_shim_hdr); 47 } 48 49 static const struct ip_tunnel_encap_ops mpls_iptun_ops = { 50 .encap_hlen = ipgre_mpls_encap_hlen, 51 }; 52 53 static int ipgre_tunnel_encap_add_mpls_ops(void) 54 { 55 return ip_tunnel_encap_add_ops(&mpls_iptun_ops, TUNNEL_ENCAP_MPLS); 56 } 57 58 static void ipgre_tunnel_encap_del_mpls_ops(void) 59 { 60 ip_tunnel_encap_del_ops(&mpls_iptun_ops, TUNNEL_ENCAP_MPLS); 61 } 62 #else 63 static int ipgre_tunnel_encap_add_mpls_ops(void) 64 { 65 return 0; 66 } 67 68 static void ipgre_tunnel_encap_del_mpls_ops(void) 69 { 70 } 71 #endif 72 73 static void rtmsg_lfib(int event, u32 label, struct mpls_route *rt, 74 struct nlmsghdr *nlh, struct net *net, u32 portid, 75 unsigned int nlm_flags); 76 77 static struct mpls_route *mpls_route_input(struct net *net, unsigned int index) 78 { 79 struct mpls_route __rcu **platform_label; 80 81 platform_label = mpls_dereference(net, net->mpls.platform_label); 82 return mpls_dereference(net, platform_label[index]); 83 } 84 85 static struct mpls_route __rcu **mpls_platform_label_rcu(struct net *net, size_t *platform_labels) 86 { 87 struct mpls_route __rcu **platform_label; 88 unsigned int sequence; 89 90 do { 91 sequence = read_seqcount_begin(&net->mpls.platform_label_seq); 92 platform_label = rcu_dereference(net->mpls.platform_label); 93 *platform_labels = net->mpls.platform_labels; 94 } while (read_seqcount_retry(&net->mpls.platform_label_seq, sequence)); 95 96 return platform_label; 97 } 98 99 static struct mpls_route *mpls_route_input_rcu(struct net *net, unsigned int index) 100 { 101 struct mpls_route __rcu **platform_label; 102 size_t platform_labels; 103 104 platform_label = mpls_platform_label_rcu(net, &platform_labels); 105 106 if (index >= platform_labels) 107 return NULL; 108 109 return rcu_dereference(platform_label[index]); 110 } 111 112 bool mpls_output_possible(const struct net_device *dev) 113 { 114 return dev && (dev->flags & IFF_UP) && netif_carrier_ok(dev); 115 } 116 EXPORT_SYMBOL_GPL(mpls_output_possible); 117 118 static u8 *__mpls_nh_via(struct mpls_route *rt, struct mpls_nh *nh) 119 { 120 return (u8 *)nh + rt->rt_via_offset; 121 } 122 123 static const u8 *mpls_nh_via(const struct mpls_route *rt, 124 const struct mpls_nh *nh) 125 { 126 return __mpls_nh_via((struct mpls_route *)rt, (struct mpls_nh *)nh); 127 } 128 129 static unsigned int mpls_nh_header_size(const struct mpls_nh *nh) 130 { 131 /* The size of the layer 2.5 labels to be added for this route */ 132 return nh->nh_labels * sizeof(struct mpls_shim_hdr); 133 } 134 135 unsigned int mpls_dev_mtu(const struct net_device *dev) 136 { 137 /* The amount of data the layer 2 frame can hold */ 138 return dev->mtu; 139 } 140 EXPORT_SYMBOL_GPL(mpls_dev_mtu); 141 142 bool mpls_pkt_too_big(const struct sk_buff *skb, unsigned int mtu) 143 { 144 if (skb->len <= mtu) 145 return false; 146 147 if (skb_is_gso(skb) && skb_gso_validate_network_len(skb, mtu)) 148 return false; 149 150 return true; 151 } 152 EXPORT_SYMBOL_GPL(mpls_pkt_too_big); 153 154 void mpls_stats_inc_outucastpkts(struct net *net, 155 struct net_device *dev, 156 const struct sk_buff *skb) 157 { 158 struct mpls_dev *mdev; 159 160 if (skb->protocol == htons(ETH_P_MPLS_UC)) { 161 mdev = mpls_dev_rcu(dev); 162 if (mdev) 163 MPLS_INC_STATS_LEN(mdev, skb->len, 164 tx_packets, 165 tx_bytes); 166 } else if (skb->protocol == htons(ETH_P_IP)) { 167 IP_UPD_PO_STATS(net, IPSTATS_MIB_OUT, skb->len); 168 #if IS_ENABLED(CONFIG_IPV6) 169 } else if (skb->protocol == htons(ETH_P_IPV6)) { 170 struct inet6_dev *in6dev = in6_dev_rcu(dev); 171 172 if (in6dev) 173 IP6_UPD_PO_STATS(net, in6dev, 174 IPSTATS_MIB_OUT, skb->len); 175 #endif 176 } 177 } 178 EXPORT_SYMBOL_GPL(mpls_stats_inc_outucastpkts); 179 180 static u32 mpls_multipath_hash(struct mpls_route *rt, struct sk_buff *skb) 181 { 182 struct mpls_entry_decoded dec; 183 unsigned int mpls_hdr_len = 0; 184 struct mpls_shim_hdr *hdr; 185 bool eli_seen = false; 186 int label_index; 187 u32 hash = 0; 188 189 for (label_index = 0; label_index < MAX_MP_SELECT_LABELS; 190 label_index++) { 191 mpls_hdr_len += sizeof(*hdr); 192 if (!pskb_may_pull(skb, mpls_hdr_len)) 193 break; 194 195 /* Read and decode the current label */ 196 hdr = mpls_hdr(skb) + label_index; 197 dec = mpls_entry_decode(hdr); 198 199 /* RFC6790 - reserved labels MUST NOT be used as keys 200 * for the load-balancing function 201 */ 202 if (likely(dec.label >= MPLS_LABEL_FIRST_UNRESERVED)) { 203 hash = jhash_1word(dec.label, hash); 204 205 /* The entropy label follows the entropy label 206 * indicator, so this means that the entropy 207 * label was just added to the hash - no need to 208 * go any deeper either in the label stack or in the 209 * payload 210 */ 211 if (eli_seen) 212 break; 213 } else if (dec.label == MPLS_LABEL_ENTROPY) { 214 eli_seen = true; 215 } 216 217 if (!dec.bos) 218 continue; 219 220 /* found bottom label; does skb have room for a header? */ 221 if (pskb_may_pull(skb, mpls_hdr_len + sizeof(struct iphdr))) { 222 const struct iphdr *v4hdr; 223 224 v4hdr = (const struct iphdr *)(hdr + 1); 225 if (v4hdr->version == 4) { 226 hash = jhash_3words(ntohl(v4hdr->saddr), 227 ntohl(v4hdr->daddr), 228 v4hdr->protocol, hash); 229 } else if (v4hdr->version == 6 && 230 pskb_may_pull(skb, mpls_hdr_len + 231 sizeof(struct ipv6hdr))) { 232 const struct ipv6hdr *v6hdr; 233 234 v6hdr = (const struct ipv6hdr *)(hdr + 1); 235 hash = __ipv6_addr_jhash(&v6hdr->saddr, hash); 236 hash = __ipv6_addr_jhash(&v6hdr->daddr, hash); 237 hash = jhash_1word(v6hdr->nexthdr, hash); 238 } 239 } 240 241 break; 242 } 243 244 return hash; 245 } 246 247 static struct mpls_nh *mpls_get_nexthop(struct mpls_route *rt, u8 index) 248 { 249 return (struct mpls_nh *)((u8 *)rt->rt_nh + index * rt->rt_nh_size); 250 } 251 252 /* number of alive nexthops (rt->rt_nhn_alive) and the flags for 253 * a next hop (nh->nh_flags) are modified by netdev event handlers. 254 * Since those fields can change at any moment, use READ_ONCE to 255 * access both. 256 */ 257 static const struct mpls_nh *mpls_select_multipath(struct mpls_route *rt, 258 struct sk_buff *skb) 259 { 260 u32 hash = 0; 261 int nh_index = 0; 262 int n = 0; 263 u8 alive; 264 265 /* No need to look further into packet if there's only 266 * one path 267 */ 268 if (rt->rt_nhn == 1) 269 return rt->rt_nh; 270 271 alive = READ_ONCE(rt->rt_nhn_alive); 272 if (alive == 0) 273 return NULL; 274 275 hash = mpls_multipath_hash(rt, skb); 276 nh_index = hash % alive; 277 if (alive == rt->rt_nhn) 278 goto out; 279 for_nexthops(rt) { 280 unsigned int nh_flags = READ_ONCE(nh->nh_flags); 281 282 if (nh_flags & (RTNH_F_DEAD | RTNH_F_LINKDOWN)) 283 continue; 284 if (n == nh_index) 285 return nh; 286 n++; 287 } endfor_nexthops(rt); 288 289 out: 290 return mpls_get_nexthop(rt, nh_index); 291 } 292 293 static bool mpls_egress(struct net *net, struct mpls_route *rt, 294 struct sk_buff *skb, struct mpls_entry_decoded dec) 295 { 296 enum mpls_payload_type payload_type; 297 bool success = false; 298 299 /* The IPv4 code below accesses through the IPv4 header 300 * checksum, which is 12 bytes into the packet. 301 * The IPv6 code below accesses through the IPv6 hop limit 302 * which is 8 bytes into the packet. 303 * 304 * For all supported cases there should always be at least 12 305 * bytes of packet data present. The IPv4 header is 20 bytes 306 * without options and the IPv6 header is always 40 bytes 307 * long. 308 */ 309 if (!pskb_may_pull(skb, 12)) 310 return false; 311 312 payload_type = rt->rt_payload_type; 313 if (payload_type == MPT_UNSPEC) 314 payload_type = ip_hdr(skb)->version; 315 316 switch (payload_type) { 317 case MPT_IPV4: { 318 struct iphdr *hdr4 = ip_hdr(skb); 319 u8 new_ttl; 320 skb->protocol = htons(ETH_P_IP); 321 322 /* If propagating TTL, take the decremented TTL from 323 * the incoming MPLS header, otherwise decrement the 324 * TTL, but only if not 0 to avoid underflow. 325 */ 326 if (rt->rt_ttl_propagate == MPLS_TTL_PROP_ENABLED || 327 (rt->rt_ttl_propagate == MPLS_TTL_PROP_DEFAULT && 328 net->mpls.ip_ttl_propagate)) 329 new_ttl = dec.ttl; 330 else 331 new_ttl = hdr4->ttl ? hdr4->ttl - 1 : 0; 332 333 csum_replace2(&hdr4->check, 334 htons(hdr4->ttl << 8), 335 htons(new_ttl << 8)); 336 hdr4->ttl = new_ttl; 337 success = true; 338 break; 339 } 340 case MPT_IPV6: { 341 struct ipv6hdr *hdr6 = ipv6_hdr(skb); 342 skb->protocol = htons(ETH_P_IPV6); 343 344 /* If propagating TTL, take the decremented TTL from 345 * the incoming MPLS header, otherwise decrement the 346 * hop limit, but only if not 0 to avoid underflow. 347 */ 348 if (rt->rt_ttl_propagate == MPLS_TTL_PROP_ENABLED || 349 (rt->rt_ttl_propagate == MPLS_TTL_PROP_DEFAULT && 350 net->mpls.ip_ttl_propagate)) 351 hdr6->hop_limit = dec.ttl; 352 else if (hdr6->hop_limit) 353 hdr6->hop_limit = hdr6->hop_limit - 1; 354 success = true; 355 break; 356 } 357 case MPT_UNSPEC: 358 /* Should have decided which protocol it is by now */ 359 break; 360 } 361 362 return success; 363 } 364 365 static int mpls_forward(struct sk_buff *skb, struct net_device *dev, 366 struct packet_type *pt, struct net_device *orig_dev) 367 { 368 struct net *net = dev_net_rcu(dev); 369 struct mpls_shim_hdr *hdr; 370 const struct mpls_nh *nh; 371 struct mpls_route *rt; 372 struct mpls_entry_decoded dec; 373 struct net_device *out_dev; 374 struct mpls_dev *out_mdev; 375 struct mpls_dev *mdev; 376 unsigned int hh_len; 377 unsigned int new_header_size; 378 unsigned int mtu; 379 int err; 380 381 /* Careful this entire function runs inside of an rcu critical section */ 382 383 mdev = mpls_dev_rcu(dev); 384 if (!mdev) 385 goto drop; 386 387 MPLS_INC_STATS_LEN(mdev, skb->len, rx_packets, 388 rx_bytes); 389 390 if (!mdev->input_enabled) { 391 MPLS_INC_STATS(mdev, rx_dropped); 392 goto drop; 393 } 394 395 if (skb->pkt_type != PACKET_HOST) 396 goto err; 397 398 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL) 399 goto err; 400 401 if (!pskb_may_pull(skb, sizeof(*hdr))) 402 goto err; 403 404 skb_dst_drop(skb); 405 406 /* Read and decode the label */ 407 hdr = mpls_hdr(skb); 408 dec = mpls_entry_decode(hdr); 409 410 rt = mpls_route_input_rcu(net, dec.label); 411 if (!rt) { 412 MPLS_INC_STATS(mdev, rx_noroute); 413 goto drop; 414 } 415 416 nh = mpls_select_multipath(rt, skb); 417 if (!nh) 418 goto err; 419 420 /* Pop the label */ 421 skb_pull(skb, sizeof(*hdr)); 422 skb_reset_network_header(skb); 423 424 skb_orphan(skb); 425 426 if (skb_warn_if_lro(skb)) 427 goto err; 428 429 skb_forward_csum(skb); 430 431 /* Verify ttl is valid */ 432 if (dec.ttl <= 1) 433 goto err; 434 435 /* Find the output device */ 436 out_dev = nh->nh_dev; 437 if (!mpls_output_possible(out_dev)) 438 goto tx_err; 439 440 /* Verify the destination can hold the packet */ 441 new_header_size = mpls_nh_header_size(nh); 442 mtu = mpls_dev_mtu(out_dev); 443 if (mpls_pkt_too_big(skb, mtu - new_header_size)) 444 goto tx_err; 445 446 hh_len = LL_RESERVED_SPACE(out_dev); 447 if (!out_dev->header_ops) 448 hh_len = 0; 449 450 /* Ensure there is enough space for the headers in the skb */ 451 if (skb_cow(skb, hh_len + new_header_size)) 452 goto tx_err; 453 454 skb->dev = out_dev; 455 skb->protocol = htons(ETH_P_MPLS_UC); 456 457 dec.ttl -= 1; 458 if (unlikely(!new_header_size && dec.bos)) { 459 /* Penultimate hop popping */ 460 if (!mpls_egress(net, rt, skb, dec)) 461 goto err; 462 } else { 463 bool bos; 464 int i; 465 skb_push(skb, new_header_size); 466 skb_reset_network_header(skb); 467 /* Push the new labels */ 468 hdr = mpls_hdr(skb); 469 bos = dec.bos; 470 for (i = nh->nh_labels - 1; i >= 0; i--) { 471 hdr[i] = mpls_entry_encode(nh->nh_label[i], 472 dec.ttl, 0, bos); 473 bos = false; 474 } 475 } 476 477 mpls_stats_inc_outucastpkts(net, out_dev, skb); 478 479 /* If via wasn't specified then send out using device address */ 480 if (nh->nh_via_table == MPLS_NEIGH_TABLE_UNSPEC) 481 err = neigh_xmit(NEIGH_LINK_TABLE, out_dev, 482 out_dev->dev_addr, skb); 483 else 484 err = neigh_xmit(nh->nh_via_table, out_dev, 485 mpls_nh_via(rt, nh), skb); 486 if (err) 487 net_dbg_ratelimited("%s: packet transmission failed: %d\n", 488 __func__, err); 489 return 0; 490 491 tx_err: 492 out_mdev = out_dev ? mpls_dev_rcu(out_dev) : NULL; 493 if (out_mdev) 494 MPLS_INC_STATS(out_mdev, tx_errors); 495 goto drop; 496 err: 497 MPLS_INC_STATS(mdev, rx_errors); 498 drop: 499 kfree_skb(skb); 500 return NET_RX_DROP; 501 } 502 503 static struct packet_type mpls_packet_type __read_mostly = { 504 .type = cpu_to_be16(ETH_P_MPLS_UC), 505 .func = mpls_forward, 506 }; 507 508 static const struct nla_policy rtm_mpls_policy[RTA_MAX+1] = { 509 [RTA_DST] = { .type = NLA_U32 }, 510 [RTA_OIF] = { .type = NLA_U32 }, 511 [RTA_TTL_PROPAGATE] = { .type = NLA_U8 }, 512 }; 513 514 struct mpls_route_config { 515 u32 rc_protocol; 516 u32 rc_ifindex; 517 u8 rc_via_table; 518 u8 rc_via_alen; 519 u8 rc_via[MAX_VIA_ALEN]; 520 u32 rc_label; 521 u8 rc_ttl_propagate; 522 u8 rc_output_labels; 523 u32 rc_output_label[MAX_NEW_LABELS]; 524 u32 rc_nlflags; 525 enum mpls_payload_type rc_payload_type; 526 struct nl_info rc_nlinfo; 527 struct rtnexthop *rc_mp; 528 int rc_mp_len; 529 }; 530 531 /* all nexthops within a route have the same size based on max 532 * number of labels and max via length for a hop 533 */ 534 static struct mpls_route *mpls_rt_alloc(u8 num_nh, u8 max_alen, u8 max_labels) 535 { 536 u8 nh_size = MPLS_NH_SIZE(max_labels, max_alen); 537 struct mpls_route *rt; 538 size_t size; 539 540 size = sizeof(*rt) + num_nh * nh_size; 541 if (size > MAX_MPLS_ROUTE_MEM) 542 return ERR_PTR(-EINVAL); 543 544 rt = kzalloc(size, GFP_KERNEL); 545 if (!rt) 546 return ERR_PTR(-ENOMEM); 547 548 rt->rt_nhn = num_nh; 549 rt->rt_nhn_alive = num_nh; 550 rt->rt_nh_size = nh_size; 551 rt->rt_via_offset = MPLS_NH_VIA_OFF(max_labels); 552 553 return rt; 554 } 555 556 static void mpls_rt_free_rcu(struct rcu_head *head) 557 { 558 struct mpls_route *rt; 559 560 rt = container_of(head, struct mpls_route, rt_rcu); 561 562 change_nexthops(rt) { 563 netdev_put(nh->nh_dev, &nh->nh_dev_tracker); 564 } endfor_nexthops(rt); 565 566 kfree(rt); 567 } 568 569 static void mpls_rt_free(struct mpls_route *rt) 570 { 571 if (rt) 572 call_rcu(&rt->rt_rcu, mpls_rt_free_rcu); 573 } 574 575 static void mpls_notify_route(struct net *net, unsigned index, 576 struct mpls_route *old, struct mpls_route *new, 577 const struct nl_info *info) 578 { 579 struct nlmsghdr *nlh = info ? info->nlh : NULL; 580 unsigned portid = info ? info->portid : 0; 581 int event = new ? RTM_NEWROUTE : RTM_DELROUTE; 582 struct mpls_route *rt = new ? new : old; 583 unsigned nlm_flags = (old && new) ? NLM_F_REPLACE : 0; 584 /* Ignore reserved labels for now */ 585 if (rt && (index >= MPLS_LABEL_FIRST_UNRESERVED)) 586 rtmsg_lfib(event, index, rt, nlh, net, portid, nlm_flags); 587 } 588 589 static void mpls_route_update(struct net *net, unsigned index, 590 struct mpls_route *new, 591 const struct nl_info *info) 592 { 593 struct mpls_route __rcu **platform_label; 594 struct mpls_route *rt; 595 596 platform_label = mpls_dereference(net, net->mpls.platform_label); 597 rt = mpls_dereference(net, platform_label[index]); 598 rcu_assign_pointer(platform_label[index], new); 599 600 mpls_notify_route(net, index, rt, new, info); 601 602 /* If we removed a route free it now */ 603 mpls_rt_free(rt); 604 } 605 606 static unsigned int find_free_label(struct net *net) 607 { 608 unsigned int index; 609 610 for (index = MPLS_LABEL_FIRST_UNRESERVED; 611 index < net->mpls.platform_labels; 612 index++) { 613 if (!mpls_route_input(net, index)) 614 return index; 615 } 616 617 return LABEL_NOT_SPECIFIED; 618 } 619 620 #if IS_ENABLED(CONFIG_INET) 621 static struct net_device *inet_fib_lookup_dev(struct net *net, 622 struct mpls_nh *nh, 623 const void *addr) 624 { 625 struct net_device *dev; 626 struct rtable *rt; 627 struct in_addr daddr; 628 629 memcpy(&daddr, addr, sizeof(struct in_addr)); 630 rt = ip_route_output(net, daddr.s_addr, 0, 0, 0, RT_SCOPE_UNIVERSE); 631 if (IS_ERR(rt)) 632 return ERR_CAST(rt); 633 634 dev = rt->dst.dev; 635 netdev_hold(dev, &nh->nh_dev_tracker, GFP_KERNEL); 636 ip_rt_put(rt); 637 638 return dev; 639 } 640 #else 641 static struct net_device *inet_fib_lookup_dev(struct net *net, 642 struct mpls_nh *nh, 643 const void *addr) 644 { 645 return ERR_PTR(-EAFNOSUPPORT); 646 } 647 #endif 648 649 #if IS_ENABLED(CONFIG_IPV6) 650 static struct net_device *inet6_fib_lookup_dev(struct net *net, 651 struct mpls_nh *nh, 652 const void *addr) 653 { 654 struct net_device *dev; 655 struct dst_entry *dst; 656 struct flowi6 fl6; 657 658 memset(&fl6, 0, sizeof(fl6)); 659 memcpy(&fl6.daddr, addr, sizeof(struct in6_addr)); 660 dst = ip6_dst_lookup_flow(net, NULL, &fl6, NULL); 661 if (IS_ERR(dst)) 662 return ERR_CAST(dst); 663 664 dev = dst->dev; 665 netdev_hold(dev, &nh->nh_dev_tracker, GFP_KERNEL); 666 dst_release(dst); 667 668 return dev; 669 } 670 #else 671 static struct net_device *inet6_fib_lookup_dev(struct net *net, 672 struct mpls_nh *nh, 673 const void *addr) 674 { 675 return ERR_PTR(-EAFNOSUPPORT); 676 } 677 #endif 678 679 static struct net_device *find_outdev(struct net *net, 680 struct mpls_route *rt, 681 struct mpls_nh *nh, int oif) 682 { 683 struct net_device *dev = NULL; 684 685 if (!oif) { 686 switch (nh->nh_via_table) { 687 case NEIGH_ARP_TABLE: 688 dev = inet_fib_lookup_dev(net, nh, mpls_nh_via(rt, nh)); 689 break; 690 case NEIGH_ND_TABLE: 691 dev = inet6_fib_lookup_dev(net, nh, mpls_nh_via(rt, nh)); 692 break; 693 case NEIGH_LINK_TABLE: 694 break; 695 } 696 } else { 697 dev = netdev_get_by_index(net, oif, 698 &nh->nh_dev_tracker, GFP_KERNEL); 699 } 700 701 if (!dev) 702 return ERR_PTR(-ENODEV); 703 704 if (IS_ERR(dev)) 705 return dev; 706 707 nh->nh_dev = dev; 708 709 return dev; 710 } 711 712 static int mpls_nh_assign_dev(struct net *net, struct mpls_route *rt, 713 struct mpls_nh *nh, int oif) 714 { 715 struct net_device *dev = NULL; 716 int err = -ENODEV; 717 718 dev = find_outdev(net, rt, nh, oif); 719 if (IS_ERR(dev)) { 720 err = PTR_ERR(dev); 721 goto errout; 722 } 723 724 /* Ensure this is a supported device */ 725 err = -EINVAL; 726 if (!mpls_dev_get(net, dev)) 727 goto errout_put; 728 729 if ((nh->nh_via_table == NEIGH_LINK_TABLE) && 730 (dev->addr_len != nh->nh_via_alen)) 731 goto errout_put; 732 733 if (!(dev->flags & IFF_UP)) { 734 nh->nh_flags |= RTNH_F_DEAD; 735 } else { 736 unsigned int flags; 737 738 flags = netif_get_flags(dev); 739 if (!(flags & (IFF_RUNNING | IFF_LOWER_UP))) 740 nh->nh_flags |= RTNH_F_LINKDOWN; 741 } 742 743 return 0; 744 745 errout_put: 746 netdev_put(nh->nh_dev, &nh->nh_dev_tracker); 747 nh->nh_dev = NULL; 748 errout: 749 return err; 750 } 751 752 static int nla_get_via(const struct nlattr *nla, u8 *via_alen, u8 *via_table, 753 u8 via_addr[], struct netlink_ext_ack *extack) 754 { 755 struct rtvia *via = nla_data(nla); 756 int err = -EINVAL; 757 int alen; 758 759 if (nla_len(nla) < offsetof(struct rtvia, rtvia_addr)) { 760 NL_SET_ERR_MSG_ATTR(extack, nla, 761 "Invalid attribute length for RTA_VIA"); 762 goto errout; 763 } 764 alen = nla_len(nla) - 765 offsetof(struct rtvia, rtvia_addr); 766 if (alen > MAX_VIA_ALEN) { 767 NL_SET_ERR_MSG_ATTR(extack, nla, 768 "Invalid address length for RTA_VIA"); 769 goto errout; 770 } 771 772 /* Validate the address family */ 773 switch (via->rtvia_family) { 774 case AF_PACKET: 775 *via_table = NEIGH_LINK_TABLE; 776 break; 777 case AF_INET: 778 *via_table = NEIGH_ARP_TABLE; 779 if (alen != 4) 780 goto errout; 781 break; 782 case AF_INET6: 783 *via_table = NEIGH_ND_TABLE; 784 if (alen != 16) 785 goto errout; 786 break; 787 default: 788 /* Unsupported address family */ 789 goto errout; 790 } 791 792 memcpy(via_addr, via->rtvia_addr, alen); 793 *via_alen = alen; 794 err = 0; 795 796 errout: 797 return err; 798 } 799 800 static int mpls_nh_build_from_cfg(struct mpls_route_config *cfg, 801 struct mpls_route *rt) 802 { 803 struct net *net = cfg->rc_nlinfo.nl_net; 804 struct mpls_nh *nh = rt->rt_nh; 805 int err; 806 int i; 807 808 if (!nh) 809 return -ENOMEM; 810 811 nh->nh_labels = cfg->rc_output_labels; 812 for (i = 0; i < nh->nh_labels; i++) 813 nh->nh_label[i] = cfg->rc_output_label[i]; 814 815 nh->nh_via_table = cfg->rc_via_table; 816 memcpy(__mpls_nh_via(rt, nh), cfg->rc_via, cfg->rc_via_alen); 817 nh->nh_via_alen = cfg->rc_via_alen; 818 819 err = mpls_nh_assign_dev(net, rt, nh, cfg->rc_ifindex); 820 if (err) 821 goto errout; 822 823 if (nh->nh_flags & (RTNH_F_DEAD | RTNH_F_LINKDOWN)) 824 rt->rt_nhn_alive--; 825 826 return 0; 827 828 errout: 829 return err; 830 } 831 832 static int mpls_nh_build(struct net *net, struct mpls_route *rt, 833 struct mpls_nh *nh, int oif, struct nlattr *via, 834 struct nlattr *newdst, u8 max_labels, 835 struct netlink_ext_ack *extack) 836 { 837 int err = -ENOMEM; 838 839 if (!nh) 840 goto errout; 841 842 if (newdst) { 843 err = nla_get_labels(newdst, max_labels, &nh->nh_labels, 844 nh->nh_label, extack); 845 if (err) 846 goto errout; 847 } 848 849 if (via) { 850 err = nla_get_via(via, &nh->nh_via_alen, &nh->nh_via_table, 851 __mpls_nh_via(rt, nh), extack); 852 if (err) 853 goto errout; 854 } else { 855 nh->nh_via_table = MPLS_NEIGH_TABLE_UNSPEC; 856 } 857 858 err = mpls_nh_assign_dev(net, rt, nh, oif); 859 if (err) 860 goto errout; 861 862 return 0; 863 864 errout: 865 return err; 866 } 867 868 static u8 mpls_count_nexthops(struct rtnexthop *rtnh, int len, 869 u8 cfg_via_alen, u8 *max_via_alen, 870 u8 *max_labels) 871 { 872 int remaining = len; 873 u8 nhs = 0; 874 875 *max_via_alen = 0; 876 *max_labels = 0; 877 878 while (rtnh_ok(rtnh, remaining)) { 879 struct nlattr *nla, *attrs = rtnh_attrs(rtnh); 880 int attrlen; 881 u8 n_labels = 0; 882 883 attrlen = rtnh_attrlen(rtnh); 884 nla = nla_find(attrs, attrlen, RTA_VIA); 885 if (nla && nla_len(nla) >= 886 offsetof(struct rtvia, rtvia_addr)) { 887 int via_alen = nla_len(nla) - 888 offsetof(struct rtvia, rtvia_addr); 889 890 if (via_alen <= MAX_VIA_ALEN) 891 *max_via_alen = max_t(u16, *max_via_alen, 892 via_alen); 893 } 894 895 nla = nla_find(attrs, attrlen, RTA_NEWDST); 896 if (nla && 897 nla_get_labels(nla, MAX_NEW_LABELS, &n_labels, 898 NULL, NULL) != 0) 899 return 0; 900 901 *max_labels = max_t(u8, *max_labels, n_labels); 902 903 /* number of nexthops is tracked by a u8. 904 * Check for overflow. 905 */ 906 if (nhs == 255) 907 return 0; 908 nhs++; 909 910 rtnh = rtnh_next(rtnh, &remaining); 911 } 912 913 /* leftover implies invalid nexthop configuration, discard it */ 914 return remaining > 0 ? 0 : nhs; 915 } 916 917 static int mpls_nh_build_multi(struct mpls_route_config *cfg, 918 struct mpls_route *rt, u8 max_labels, 919 struct netlink_ext_ack *extack) 920 { 921 struct rtnexthop *rtnh = cfg->rc_mp; 922 struct nlattr *nla_via, *nla_newdst; 923 int remaining = cfg->rc_mp_len; 924 int err = 0; 925 u8 nhs = 0; 926 927 change_nexthops(rt) { 928 int attrlen; 929 930 nla_via = NULL; 931 nla_newdst = NULL; 932 933 err = -EINVAL; 934 if (!rtnh_ok(rtnh, remaining)) 935 goto errout; 936 937 /* neither weighted multipath nor any flags 938 * are supported 939 */ 940 if (rtnh->rtnh_hops || rtnh->rtnh_flags) 941 goto errout; 942 943 attrlen = rtnh_attrlen(rtnh); 944 if (attrlen > 0) { 945 struct nlattr *attrs = rtnh_attrs(rtnh); 946 947 nla_via = nla_find(attrs, attrlen, RTA_VIA); 948 nla_newdst = nla_find(attrs, attrlen, RTA_NEWDST); 949 } 950 951 err = mpls_nh_build(cfg->rc_nlinfo.nl_net, rt, nh, 952 rtnh->rtnh_ifindex, nla_via, nla_newdst, 953 max_labels, extack); 954 if (err) 955 goto errout; 956 957 if (nh->nh_flags & (RTNH_F_DEAD | RTNH_F_LINKDOWN)) 958 rt->rt_nhn_alive--; 959 960 rtnh = rtnh_next(rtnh, &remaining); 961 nhs++; 962 } endfor_nexthops(rt); 963 964 rt->rt_nhn = nhs; 965 966 return 0; 967 968 errout: 969 rt->rt_nhn = nhs; 970 return err; 971 } 972 973 static bool mpls_label_ok(struct net *net, unsigned int *index, 974 struct netlink_ext_ack *extack) 975 { 976 /* Reserved labels may not be set */ 977 if (*index < MPLS_LABEL_FIRST_UNRESERVED) { 978 NL_SET_ERR_MSG(extack, 979 "Invalid label - must be MPLS_LABEL_FIRST_UNRESERVED or higher"); 980 return false; 981 } 982 983 /* The full 20 bit range may not be supported. */ 984 if (*index >= net->mpls.platform_labels) { 985 NL_SET_ERR_MSG(extack, 986 "Label >= configured maximum in platform_labels"); 987 return false; 988 } 989 990 *index = array_index_nospec(*index, net->mpls.platform_labels); 991 992 return true; 993 } 994 995 static int mpls_route_add(struct mpls_route_config *cfg, 996 struct netlink_ext_ack *extack) 997 { 998 struct net *net = cfg->rc_nlinfo.nl_net; 999 struct mpls_route *rt, *old; 1000 int err = -EINVAL; 1001 u8 max_via_alen; 1002 unsigned index; 1003 u8 max_labels; 1004 u8 nhs; 1005 1006 index = cfg->rc_label; 1007 1008 /* If a label was not specified during insert pick one */ 1009 if ((index == LABEL_NOT_SPECIFIED) && 1010 (cfg->rc_nlflags & NLM_F_CREATE)) { 1011 index = find_free_label(net); 1012 } 1013 1014 if (!mpls_label_ok(net, &index, extack)) 1015 goto errout; 1016 1017 /* Append makes no sense with mpls */ 1018 err = -EOPNOTSUPP; 1019 if (cfg->rc_nlflags & NLM_F_APPEND) { 1020 NL_SET_ERR_MSG(extack, "MPLS does not support route append"); 1021 goto errout; 1022 } 1023 1024 err = -EEXIST; 1025 old = mpls_route_input(net, index); 1026 if ((cfg->rc_nlflags & NLM_F_EXCL) && old) 1027 goto errout; 1028 1029 err = -EEXIST; 1030 if (!(cfg->rc_nlflags & NLM_F_REPLACE) && old) 1031 goto errout; 1032 1033 err = -ENOENT; 1034 if (!(cfg->rc_nlflags & NLM_F_CREATE) && !old) 1035 goto errout; 1036 1037 err = -EINVAL; 1038 if (cfg->rc_mp) { 1039 nhs = mpls_count_nexthops(cfg->rc_mp, cfg->rc_mp_len, 1040 cfg->rc_via_alen, &max_via_alen, 1041 &max_labels); 1042 } else { 1043 max_via_alen = cfg->rc_via_alen; 1044 max_labels = cfg->rc_output_labels; 1045 nhs = 1; 1046 } 1047 1048 if (nhs == 0) { 1049 NL_SET_ERR_MSG(extack, "Route does not contain a nexthop"); 1050 goto errout; 1051 } 1052 1053 rt = mpls_rt_alloc(nhs, max_via_alen, max_labels); 1054 if (IS_ERR(rt)) { 1055 err = PTR_ERR(rt); 1056 goto errout; 1057 } 1058 1059 rt->rt_protocol = cfg->rc_protocol; 1060 rt->rt_payload_type = cfg->rc_payload_type; 1061 rt->rt_ttl_propagate = cfg->rc_ttl_propagate; 1062 1063 if (cfg->rc_mp) 1064 err = mpls_nh_build_multi(cfg, rt, max_labels, extack); 1065 else 1066 err = mpls_nh_build_from_cfg(cfg, rt); 1067 if (err) 1068 goto freert; 1069 1070 mpls_route_update(net, index, rt, &cfg->rc_nlinfo); 1071 1072 return 0; 1073 1074 freert: 1075 mpls_rt_free(rt); 1076 errout: 1077 return err; 1078 } 1079 1080 static int mpls_route_del(struct mpls_route_config *cfg, 1081 struct netlink_ext_ack *extack) 1082 { 1083 struct net *net = cfg->rc_nlinfo.nl_net; 1084 unsigned index; 1085 int err = -EINVAL; 1086 1087 index = cfg->rc_label; 1088 1089 if (!mpls_label_ok(net, &index, extack)) 1090 goto errout; 1091 1092 mpls_route_update(net, index, NULL, &cfg->rc_nlinfo); 1093 1094 err = 0; 1095 errout: 1096 return err; 1097 } 1098 1099 static void mpls_get_stats(struct mpls_dev *mdev, 1100 struct mpls_link_stats *stats) 1101 { 1102 struct mpls_pcpu_stats *p; 1103 int i; 1104 1105 memset(stats, 0, sizeof(*stats)); 1106 1107 for_each_possible_cpu(i) { 1108 struct mpls_link_stats local; 1109 unsigned int start; 1110 1111 p = per_cpu_ptr(mdev->stats, i); 1112 do { 1113 start = u64_stats_fetch_begin(&p->syncp); 1114 local = p->stats; 1115 } while (u64_stats_fetch_retry(&p->syncp, start)); 1116 1117 stats->rx_packets += local.rx_packets; 1118 stats->rx_bytes += local.rx_bytes; 1119 stats->tx_packets += local.tx_packets; 1120 stats->tx_bytes += local.tx_bytes; 1121 stats->rx_errors += local.rx_errors; 1122 stats->tx_errors += local.tx_errors; 1123 stats->rx_dropped += local.rx_dropped; 1124 stats->tx_dropped += local.tx_dropped; 1125 stats->rx_noroute += local.rx_noroute; 1126 } 1127 } 1128 1129 static int mpls_fill_stats_af(struct sk_buff *skb, 1130 const struct net_device *dev) 1131 { 1132 struct mpls_link_stats *stats; 1133 struct mpls_dev *mdev; 1134 struct nlattr *nla; 1135 1136 mdev = mpls_dev_rcu(dev); 1137 if (!mdev) 1138 return -ENODATA; 1139 1140 nla = nla_reserve_64bit(skb, MPLS_STATS_LINK, 1141 sizeof(struct mpls_link_stats), 1142 MPLS_STATS_UNSPEC); 1143 if (!nla) 1144 return -EMSGSIZE; 1145 1146 stats = nla_data(nla); 1147 mpls_get_stats(mdev, stats); 1148 1149 return 0; 1150 } 1151 1152 static size_t mpls_get_stats_af_size(const struct net_device *dev) 1153 { 1154 struct mpls_dev *mdev; 1155 1156 mdev = mpls_dev_rcu(dev); 1157 if (!mdev) 1158 return 0; 1159 1160 return nla_total_size_64bit(sizeof(struct mpls_link_stats)); 1161 } 1162 1163 static int mpls_netconf_fill_devconf(struct sk_buff *skb, struct mpls_dev *mdev, 1164 u32 portid, u32 seq, int event, 1165 unsigned int flags, int type) 1166 { 1167 struct nlmsghdr *nlh; 1168 struct netconfmsg *ncm; 1169 bool all = false; 1170 1171 nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg), 1172 flags); 1173 if (!nlh) 1174 return -EMSGSIZE; 1175 1176 if (type == NETCONFA_ALL) 1177 all = true; 1178 1179 ncm = nlmsg_data(nlh); 1180 ncm->ncm_family = AF_MPLS; 1181 1182 if (nla_put_s32(skb, NETCONFA_IFINDEX, mdev->dev->ifindex) < 0) 1183 goto nla_put_failure; 1184 1185 if ((all || type == NETCONFA_INPUT) && 1186 nla_put_s32(skb, NETCONFA_INPUT, 1187 READ_ONCE(mdev->input_enabled)) < 0) 1188 goto nla_put_failure; 1189 1190 nlmsg_end(skb, nlh); 1191 return 0; 1192 1193 nla_put_failure: 1194 nlmsg_cancel(skb, nlh); 1195 return -EMSGSIZE; 1196 } 1197 1198 static int mpls_netconf_msgsize_devconf(int type) 1199 { 1200 int size = NLMSG_ALIGN(sizeof(struct netconfmsg)) 1201 + nla_total_size(4); /* NETCONFA_IFINDEX */ 1202 bool all = false; 1203 1204 if (type == NETCONFA_ALL) 1205 all = true; 1206 1207 if (all || type == NETCONFA_INPUT) 1208 size += nla_total_size(4); 1209 1210 return size; 1211 } 1212 1213 static void mpls_netconf_notify_devconf(struct net *net, int event, 1214 int type, struct mpls_dev *mdev) 1215 { 1216 struct sk_buff *skb; 1217 int err = -ENOBUFS; 1218 1219 skb = nlmsg_new(mpls_netconf_msgsize_devconf(type), GFP_KERNEL); 1220 if (!skb) 1221 goto errout; 1222 1223 err = mpls_netconf_fill_devconf(skb, mdev, 0, 0, event, 0, type); 1224 if (err < 0) { 1225 /* -EMSGSIZE implies BUG in mpls_netconf_msgsize_devconf() */ 1226 WARN_ON(err == -EMSGSIZE); 1227 kfree_skb(skb); 1228 goto errout; 1229 } 1230 1231 rtnl_notify(skb, net, 0, RTNLGRP_MPLS_NETCONF, NULL, GFP_KERNEL); 1232 return; 1233 errout: 1234 rtnl_set_sk_err(net, RTNLGRP_MPLS_NETCONF, err); 1235 } 1236 1237 static const struct nla_policy devconf_mpls_policy[NETCONFA_MAX + 1] = { 1238 [NETCONFA_IFINDEX] = { .len = sizeof(int) }, 1239 }; 1240 1241 static int mpls_netconf_valid_get_req(struct sk_buff *skb, 1242 const struct nlmsghdr *nlh, 1243 struct nlattr **tb, 1244 struct netlink_ext_ack *extack) 1245 { 1246 int i, err; 1247 1248 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(struct netconfmsg))) { 1249 NL_SET_ERR_MSG_MOD(extack, 1250 "Invalid header for netconf get request"); 1251 return -EINVAL; 1252 } 1253 1254 if (!netlink_strict_get_check(skb)) 1255 return nlmsg_parse_deprecated(nlh, sizeof(struct netconfmsg), 1256 tb, NETCONFA_MAX, 1257 devconf_mpls_policy, extack); 1258 1259 err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct netconfmsg), 1260 tb, NETCONFA_MAX, 1261 devconf_mpls_policy, extack); 1262 if (err) 1263 return err; 1264 1265 for (i = 0; i <= NETCONFA_MAX; i++) { 1266 if (!tb[i]) 1267 continue; 1268 1269 switch (i) { 1270 case NETCONFA_IFINDEX: 1271 break; 1272 default: 1273 NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in netconf get request"); 1274 return -EINVAL; 1275 } 1276 } 1277 1278 return 0; 1279 } 1280 1281 static int mpls_netconf_get_devconf(struct sk_buff *in_skb, 1282 struct nlmsghdr *nlh, 1283 struct netlink_ext_ack *extack) 1284 { 1285 struct net *net = sock_net(in_skb->sk); 1286 struct nlattr *tb[NETCONFA_MAX + 1]; 1287 struct net_device *dev; 1288 struct mpls_dev *mdev; 1289 struct sk_buff *skb; 1290 int ifindex; 1291 int err; 1292 1293 err = mpls_netconf_valid_get_req(in_skb, nlh, tb, extack); 1294 if (err < 0) 1295 goto errout; 1296 1297 if (!tb[NETCONFA_IFINDEX]) { 1298 err = -EINVAL; 1299 goto errout; 1300 } 1301 1302 ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]); 1303 1304 skb = nlmsg_new(mpls_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL); 1305 if (!skb) { 1306 err = -ENOBUFS; 1307 goto errout; 1308 } 1309 1310 rcu_read_lock(); 1311 1312 dev = dev_get_by_index_rcu(net, ifindex); 1313 if (!dev) { 1314 err = -EINVAL; 1315 goto errout_unlock; 1316 } 1317 1318 mdev = mpls_dev_rcu(dev); 1319 if (!mdev) { 1320 err = -EINVAL; 1321 goto errout_unlock; 1322 } 1323 1324 err = mpls_netconf_fill_devconf(skb, mdev, 1325 NETLINK_CB(in_skb).portid, 1326 nlh->nlmsg_seq, RTM_NEWNETCONF, 0, 1327 NETCONFA_ALL); 1328 if (err < 0) { 1329 /* -EMSGSIZE implies BUG in mpls_netconf_msgsize_devconf() */ 1330 WARN_ON(err == -EMSGSIZE); 1331 goto errout_unlock; 1332 } 1333 1334 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid); 1335 1336 rcu_read_unlock(); 1337 errout: 1338 return err; 1339 1340 errout_unlock: 1341 rcu_read_unlock(); 1342 kfree_skb(skb); 1343 goto errout; 1344 } 1345 1346 static int mpls_netconf_dump_devconf(struct sk_buff *skb, 1347 struct netlink_callback *cb) 1348 { 1349 const struct nlmsghdr *nlh = cb->nlh; 1350 struct net *net = sock_net(skb->sk); 1351 struct { 1352 unsigned long ifindex; 1353 } *ctx = (void *)cb->ctx; 1354 struct net_device *dev; 1355 struct mpls_dev *mdev; 1356 int err = 0; 1357 1358 if (cb->strict_check) { 1359 struct netlink_ext_ack *extack = cb->extack; 1360 struct netconfmsg *ncm; 1361 1362 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ncm))) { 1363 NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf dump request"); 1364 return -EINVAL; 1365 } 1366 1367 if (nlmsg_attrlen(nlh, sizeof(*ncm))) { 1368 NL_SET_ERR_MSG_MOD(extack, "Invalid data after header in netconf dump request"); 1369 return -EINVAL; 1370 } 1371 } 1372 1373 rcu_read_lock(); 1374 for_each_netdev_dump(net, dev, ctx->ifindex) { 1375 mdev = mpls_dev_rcu(dev); 1376 if (!mdev) 1377 continue; 1378 err = mpls_netconf_fill_devconf(skb, mdev, 1379 NETLINK_CB(cb->skb).portid, 1380 nlh->nlmsg_seq, 1381 RTM_NEWNETCONF, 1382 NLM_F_MULTI, 1383 NETCONFA_ALL); 1384 if (err < 0) 1385 break; 1386 } 1387 rcu_read_unlock(); 1388 1389 return err; 1390 } 1391 1392 #define MPLS_PERDEV_SYSCTL_OFFSET(field) \ 1393 (&((struct mpls_dev *)0)->field) 1394 1395 static int mpls_conf_proc(const struct ctl_table *ctl, int write, 1396 void *buffer, size_t *lenp, loff_t *ppos) 1397 { 1398 int oval = *(int *)ctl->data; 1399 int ret = proc_dointvec(ctl, write, buffer, lenp, ppos); 1400 1401 if (write) { 1402 struct mpls_dev *mdev = ctl->extra1; 1403 int i = (int *)ctl->data - (int *)mdev; 1404 struct net *net = ctl->extra2; 1405 int val = *(int *)ctl->data; 1406 1407 if (i == offsetof(struct mpls_dev, input_enabled) && 1408 val != oval) { 1409 mpls_netconf_notify_devconf(net, RTM_NEWNETCONF, 1410 NETCONFA_INPUT, mdev); 1411 } 1412 } 1413 1414 return ret; 1415 } 1416 1417 static const struct ctl_table mpls_dev_table[] = { 1418 { 1419 .procname = "input", 1420 .maxlen = sizeof(int), 1421 .mode = 0644, 1422 .proc_handler = mpls_conf_proc, 1423 .data = MPLS_PERDEV_SYSCTL_OFFSET(input_enabled), 1424 }, 1425 }; 1426 1427 static int mpls_dev_sysctl_register(struct net_device *dev, 1428 struct mpls_dev *mdev) 1429 { 1430 char path[sizeof("net/mpls/conf/") + IFNAMSIZ]; 1431 size_t table_size = ARRAY_SIZE(mpls_dev_table); 1432 struct net *net = dev_net(dev); 1433 struct ctl_table *table; 1434 int i; 1435 1436 table = kmemdup(&mpls_dev_table, sizeof(mpls_dev_table), GFP_KERNEL); 1437 if (!table) 1438 goto out; 1439 1440 /* Table data contains only offsets relative to the base of 1441 * the mdev at this point, so make them absolute. 1442 */ 1443 for (i = 0; i < table_size; i++) { 1444 table[i].data = (char *)mdev + (uintptr_t)table[i].data; 1445 table[i].extra1 = mdev; 1446 table[i].extra2 = net; 1447 } 1448 1449 snprintf(path, sizeof(path), "net/mpls/conf/%s", dev->name); 1450 1451 mdev->sysctl = register_net_sysctl_sz(net, path, table, table_size); 1452 if (!mdev->sysctl) 1453 goto free; 1454 1455 mpls_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL, mdev); 1456 return 0; 1457 1458 free: 1459 kfree(table); 1460 out: 1461 mdev->sysctl = NULL; 1462 return -ENOBUFS; 1463 } 1464 1465 static void mpls_dev_sysctl_unregister(struct net_device *dev, 1466 struct mpls_dev *mdev) 1467 { 1468 struct net *net = dev_net(dev); 1469 const struct ctl_table *table; 1470 1471 if (!mdev->sysctl) 1472 return; 1473 1474 table = mdev->sysctl->ctl_table_arg; 1475 unregister_net_sysctl_table(mdev->sysctl); 1476 kfree(table); 1477 1478 mpls_netconf_notify_devconf(net, RTM_DELNETCONF, 0, mdev); 1479 } 1480 1481 static struct mpls_dev *mpls_add_dev(struct net_device *dev) 1482 { 1483 struct mpls_dev *mdev; 1484 int err = -ENOMEM; 1485 int i; 1486 1487 mdev = kzalloc_obj(*mdev); 1488 if (!mdev) 1489 return ERR_PTR(err); 1490 1491 mdev->stats = alloc_percpu(struct mpls_pcpu_stats); 1492 if (!mdev->stats) 1493 goto free; 1494 1495 for_each_possible_cpu(i) { 1496 struct mpls_pcpu_stats *mpls_stats; 1497 1498 mpls_stats = per_cpu_ptr(mdev->stats, i); 1499 u64_stats_init(&mpls_stats->syncp); 1500 } 1501 1502 mdev->dev = dev; 1503 1504 err = mpls_dev_sysctl_register(dev, mdev); 1505 if (err) 1506 goto free; 1507 1508 rcu_assign_pointer(dev->mpls_ptr, mdev); 1509 1510 return mdev; 1511 1512 free: 1513 free_percpu(mdev->stats); 1514 kfree(mdev); 1515 return ERR_PTR(err); 1516 } 1517 1518 static void mpls_dev_destroy_rcu(struct rcu_head *head) 1519 { 1520 struct mpls_dev *mdev = container_of(head, struct mpls_dev, rcu); 1521 1522 free_percpu(mdev->stats); 1523 kfree(mdev); 1524 } 1525 1526 static int mpls_ifdown(struct net_device *dev, int event) 1527 { 1528 struct net *net = dev_net(dev); 1529 unsigned int index; 1530 1531 for (index = 0; index < net->mpls.platform_labels; index++) { 1532 struct mpls_route *rt; 1533 bool nh_del = false; 1534 u8 alive = 0; 1535 1536 rt = mpls_route_input(net, index); 1537 if (!rt) 1538 continue; 1539 1540 if (event == NETDEV_UNREGISTER) { 1541 u8 deleted = 0; 1542 1543 for_nexthops(rt) { 1544 if (!nh->nh_dev || nh->nh_dev == dev) 1545 deleted++; 1546 if (nh->nh_dev == dev) 1547 nh_del = true; 1548 } endfor_nexthops(rt); 1549 1550 /* if there are no more nexthops, delete the route */ 1551 if (deleted == rt->rt_nhn) { 1552 mpls_route_update(net, index, NULL, NULL); 1553 continue; 1554 } 1555 1556 if (nh_del) { 1557 size_t size = sizeof(*rt) + rt->rt_nhn * 1558 rt->rt_nh_size; 1559 struct mpls_route *orig = rt; 1560 1561 rt = kmemdup(orig, size, GFP_KERNEL); 1562 if (!rt) 1563 return -ENOMEM; 1564 } 1565 } 1566 1567 change_nexthops(rt) { 1568 unsigned int nh_flags = nh->nh_flags; 1569 1570 if (nh->nh_dev != dev) { 1571 if (nh_del) 1572 netdev_hold(nh->nh_dev, &nh->nh_dev_tracker, 1573 GFP_KERNEL); 1574 goto next; 1575 } 1576 1577 switch (event) { 1578 case NETDEV_DOWN: 1579 case NETDEV_UNREGISTER: 1580 nh_flags |= RTNH_F_DEAD; 1581 fallthrough; 1582 case NETDEV_CHANGE: 1583 nh_flags |= RTNH_F_LINKDOWN; 1584 break; 1585 } 1586 if (event == NETDEV_UNREGISTER) 1587 nh->nh_dev = NULL; 1588 1589 if (nh->nh_flags != nh_flags) 1590 WRITE_ONCE(nh->nh_flags, nh_flags); 1591 next: 1592 if (!(nh_flags & (RTNH_F_DEAD | RTNH_F_LINKDOWN))) 1593 alive++; 1594 } endfor_nexthops(rt); 1595 1596 WRITE_ONCE(rt->rt_nhn_alive, alive); 1597 1598 if (nh_del) 1599 mpls_route_update(net, index, rt, NULL); 1600 } 1601 1602 return 0; 1603 } 1604 1605 static void mpls_ifup(struct net_device *dev, unsigned int flags) 1606 { 1607 struct net *net = dev_net(dev); 1608 unsigned int index; 1609 u8 alive; 1610 1611 for (index = 0; index < net->mpls.platform_labels; index++) { 1612 struct mpls_route *rt; 1613 1614 rt = mpls_route_input(net, index); 1615 if (!rt) 1616 continue; 1617 1618 alive = 0; 1619 change_nexthops(rt) { 1620 unsigned int nh_flags = nh->nh_flags; 1621 1622 if (!(nh_flags & flags)) { 1623 alive++; 1624 continue; 1625 } 1626 if (nh->nh_dev != dev) 1627 continue; 1628 alive++; 1629 nh_flags &= ~flags; 1630 WRITE_ONCE(nh->nh_flags, nh_flags); 1631 } endfor_nexthops(rt); 1632 1633 WRITE_ONCE(rt->rt_nhn_alive, alive); 1634 } 1635 } 1636 1637 static int mpls_dev_notify(struct notifier_block *this, unsigned long event, 1638 void *ptr) 1639 { 1640 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 1641 struct net *net = dev_net(dev); 1642 struct mpls_dev *mdev; 1643 unsigned int flags; 1644 int err; 1645 1646 mutex_lock(&net->mpls.platform_mutex); 1647 1648 if (event == NETDEV_REGISTER) { 1649 mdev = mpls_add_dev(dev); 1650 if (IS_ERR(mdev)) { 1651 err = PTR_ERR(mdev); 1652 goto err; 1653 } 1654 1655 goto out; 1656 } 1657 1658 mdev = mpls_dev_get(net, dev); 1659 if (!mdev) 1660 goto out; 1661 1662 switch (event) { 1663 1664 case NETDEV_DOWN: 1665 err = mpls_ifdown(dev, event); 1666 if (err) 1667 goto err; 1668 break; 1669 case NETDEV_UP: 1670 flags = netif_get_flags(dev); 1671 if (flags & (IFF_RUNNING | IFF_LOWER_UP)) 1672 mpls_ifup(dev, RTNH_F_DEAD | RTNH_F_LINKDOWN); 1673 else 1674 mpls_ifup(dev, RTNH_F_DEAD); 1675 break; 1676 case NETDEV_CHANGE: 1677 flags = netif_get_flags(dev); 1678 if (flags & (IFF_RUNNING | IFF_LOWER_UP)) { 1679 mpls_ifup(dev, RTNH_F_DEAD | RTNH_F_LINKDOWN); 1680 } else { 1681 err = mpls_ifdown(dev, event); 1682 if (err) 1683 goto err; 1684 } 1685 break; 1686 case NETDEV_UNREGISTER: 1687 err = mpls_ifdown(dev, event); 1688 if (err) 1689 goto err; 1690 1691 mdev = mpls_dev_get(net, dev); 1692 if (mdev) { 1693 mpls_dev_sysctl_unregister(dev, mdev); 1694 RCU_INIT_POINTER(dev->mpls_ptr, NULL); 1695 call_rcu(&mdev->rcu, mpls_dev_destroy_rcu); 1696 } 1697 break; 1698 case NETDEV_CHANGENAME: 1699 mdev = mpls_dev_get(net, dev); 1700 if (mdev) { 1701 mpls_dev_sysctl_unregister(dev, mdev); 1702 err = mpls_dev_sysctl_register(dev, mdev); 1703 if (err) 1704 goto err; 1705 } 1706 break; 1707 } 1708 1709 out: 1710 mutex_unlock(&net->mpls.platform_mutex); 1711 return NOTIFY_OK; 1712 1713 err: 1714 mutex_unlock(&net->mpls.platform_mutex); 1715 return notifier_from_errno(err); 1716 } 1717 1718 static struct notifier_block mpls_dev_notifier = { 1719 .notifier_call = mpls_dev_notify, 1720 }; 1721 1722 static int nla_put_via(struct sk_buff *skb, 1723 u8 table, const void *addr, int alen) 1724 { 1725 static const int table_to_family[NEIGH_NR_TABLES + 1] = { 1726 AF_INET, AF_INET6, AF_PACKET, 1727 }; 1728 struct nlattr *nla; 1729 struct rtvia *via; 1730 int family = AF_UNSPEC; 1731 1732 nla = nla_reserve(skb, RTA_VIA, alen + 2); 1733 if (!nla) 1734 return -EMSGSIZE; 1735 1736 if (table <= NEIGH_NR_TABLES) 1737 family = table_to_family[table]; 1738 1739 via = nla_data(nla); 1740 via->rtvia_family = family; 1741 memcpy(via->rtvia_addr, addr, alen); 1742 return 0; 1743 } 1744 1745 int nla_put_labels(struct sk_buff *skb, int attrtype, 1746 u8 labels, const u32 label[]) 1747 { 1748 struct nlattr *nla; 1749 struct mpls_shim_hdr *nla_label; 1750 bool bos; 1751 int i; 1752 nla = nla_reserve(skb, attrtype, labels*4); 1753 if (!nla) 1754 return -EMSGSIZE; 1755 1756 nla_label = nla_data(nla); 1757 bos = true; 1758 for (i = labels - 1; i >= 0; i--) { 1759 nla_label[i] = mpls_entry_encode(label[i], 0, 0, bos); 1760 bos = false; 1761 } 1762 1763 return 0; 1764 } 1765 EXPORT_SYMBOL_GPL(nla_put_labels); 1766 1767 int nla_get_labels(const struct nlattr *nla, u8 max_labels, u8 *labels, 1768 u32 label[], struct netlink_ext_ack *extack) 1769 { 1770 unsigned len = nla_len(nla); 1771 struct mpls_shim_hdr *nla_label; 1772 u8 nla_labels; 1773 bool bos; 1774 int i; 1775 1776 /* len needs to be an even multiple of 4 (the label size). Number 1777 * of labels is a u8 so check for overflow. 1778 */ 1779 if (len & 3 || len / 4 > 255) { 1780 NL_SET_ERR_MSG_ATTR(extack, nla, 1781 "Invalid length for labels attribute"); 1782 return -EINVAL; 1783 } 1784 1785 /* Limit the number of new labels allowed */ 1786 nla_labels = len/4; 1787 if (nla_labels > max_labels) { 1788 NL_SET_ERR_MSG(extack, "Too many labels"); 1789 return -EINVAL; 1790 } 1791 1792 /* when label == NULL, caller wants number of labels */ 1793 if (!label) 1794 goto out; 1795 1796 nla_label = nla_data(nla); 1797 bos = true; 1798 for (i = nla_labels - 1; i >= 0; i--, bos = false) { 1799 struct mpls_entry_decoded dec; 1800 dec = mpls_entry_decode(nla_label + i); 1801 1802 /* Ensure the bottom of stack flag is properly set 1803 * and ttl and tc are both clear. 1804 */ 1805 if (dec.ttl) { 1806 NL_SET_ERR_MSG_ATTR(extack, nla, 1807 "TTL in label must be 0"); 1808 return -EINVAL; 1809 } 1810 1811 if (dec.tc) { 1812 NL_SET_ERR_MSG_ATTR(extack, nla, 1813 "Traffic class in label must be 0"); 1814 return -EINVAL; 1815 } 1816 1817 if (dec.bos != bos) { 1818 NL_SET_BAD_ATTR(extack, nla); 1819 if (bos) { 1820 NL_SET_ERR_MSG(extack, 1821 "BOS bit must be set in first label"); 1822 } else { 1823 NL_SET_ERR_MSG(extack, 1824 "BOS bit can only be set in first label"); 1825 } 1826 return -EINVAL; 1827 } 1828 1829 switch (dec.label) { 1830 case MPLS_LABEL_IMPLNULL: 1831 /* RFC3032: This is a label that an LSR may 1832 * assign and distribute, but which never 1833 * actually appears in the encapsulation. 1834 */ 1835 NL_SET_ERR_MSG_ATTR(extack, nla, 1836 "Implicit NULL Label (3) can not be used in encapsulation"); 1837 return -EINVAL; 1838 } 1839 1840 label[i] = dec.label; 1841 } 1842 out: 1843 *labels = nla_labels; 1844 return 0; 1845 } 1846 EXPORT_SYMBOL_GPL(nla_get_labels); 1847 1848 static int rtm_to_route_config(struct sk_buff *skb, 1849 struct nlmsghdr *nlh, 1850 struct mpls_route_config *cfg, 1851 struct netlink_ext_ack *extack) 1852 { 1853 struct rtmsg *rtm; 1854 struct nlattr *tb[RTA_MAX+1]; 1855 int index; 1856 int err; 1857 1858 err = nlmsg_parse_deprecated(nlh, sizeof(*rtm), tb, RTA_MAX, 1859 rtm_mpls_policy, extack); 1860 if (err < 0) 1861 goto errout; 1862 1863 err = -EINVAL; 1864 rtm = nlmsg_data(nlh); 1865 1866 if (rtm->rtm_family != AF_MPLS) { 1867 NL_SET_ERR_MSG(extack, "Invalid address family in rtmsg"); 1868 goto errout; 1869 } 1870 if (rtm->rtm_dst_len != 20) { 1871 NL_SET_ERR_MSG(extack, "rtm_dst_len must be 20 for MPLS"); 1872 goto errout; 1873 } 1874 if (rtm->rtm_src_len != 0) { 1875 NL_SET_ERR_MSG(extack, "rtm_src_len must be 0 for MPLS"); 1876 goto errout; 1877 } 1878 if (rtm->rtm_tos != 0) { 1879 NL_SET_ERR_MSG(extack, "rtm_tos must be 0 for MPLS"); 1880 goto errout; 1881 } 1882 if (rtm->rtm_table != RT_TABLE_MAIN) { 1883 NL_SET_ERR_MSG(extack, 1884 "MPLS only supports the main route table"); 1885 goto errout; 1886 } 1887 /* Any value is acceptable for rtm_protocol */ 1888 1889 /* As mpls uses destination specific addresses 1890 * (or source specific address in the case of multicast) 1891 * all addresses have universal scope. 1892 */ 1893 if (rtm->rtm_scope != RT_SCOPE_UNIVERSE) { 1894 NL_SET_ERR_MSG(extack, 1895 "Invalid route scope - MPLS only supports UNIVERSE"); 1896 goto errout; 1897 } 1898 if (rtm->rtm_type != RTN_UNICAST) { 1899 NL_SET_ERR_MSG(extack, 1900 "Invalid route type - MPLS only supports UNICAST"); 1901 goto errout; 1902 } 1903 if (rtm->rtm_flags != 0) { 1904 NL_SET_ERR_MSG(extack, "rtm_flags must be 0 for MPLS"); 1905 goto errout; 1906 } 1907 1908 cfg->rc_label = LABEL_NOT_SPECIFIED; 1909 cfg->rc_protocol = rtm->rtm_protocol; 1910 cfg->rc_via_table = MPLS_NEIGH_TABLE_UNSPEC; 1911 cfg->rc_ttl_propagate = MPLS_TTL_PROP_DEFAULT; 1912 cfg->rc_nlflags = nlh->nlmsg_flags; 1913 cfg->rc_nlinfo.portid = NETLINK_CB(skb).portid; 1914 cfg->rc_nlinfo.nlh = nlh; 1915 cfg->rc_nlinfo.nl_net = sock_net(skb->sk); 1916 1917 for (index = 0; index <= RTA_MAX; index++) { 1918 struct nlattr *nla = tb[index]; 1919 if (!nla) 1920 continue; 1921 1922 switch (index) { 1923 case RTA_OIF: 1924 cfg->rc_ifindex = nla_get_u32(nla); 1925 break; 1926 case RTA_NEWDST: 1927 if (nla_get_labels(nla, MAX_NEW_LABELS, 1928 &cfg->rc_output_labels, 1929 cfg->rc_output_label, extack)) 1930 goto errout; 1931 break; 1932 case RTA_DST: 1933 { 1934 u8 label_count; 1935 if (nla_get_labels(nla, 1, &label_count, 1936 &cfg->rc_label, extack)) 1937 goto errout; 1938 1939 if (!mpls_label_ok(cfg->rc_nlinfo.nl_net, 1940 &cfg->rc_label, extack)) 1941 goto errout; 1942 break; 1943 } 1944 case RTA_GATEWAY: 1945 NL_SET_ERR_MSG(extack, "MPLS does not support RTA_GATEWAY attribute"); 1946 goto errout; 1947 case RTA_VIA: 1948 { 1949 if (nla_get_via(nla, &cfg->rc_via_alen, 1950 &cfg->rc_via_table, cfg->rc_via, 1951 extack)) 1952 goto errout; 1953 break; 1954 } 1955 case RTA_MULTIPATH: 1956 { 1957 cfg->rc_mp = nla_data(nla); 1958 cfg->rc_mp_len = nla_len(nla); 1959 break; 1960 } 1961 case RTA_TTL_PROPAGATE: 1962 { 1963 u8 ttl_propagate = nla_get_u8(nla); 1964 1965 if (ttl_propagate > 1) { 1966 NL_SET_ERR_MSG_ATTR(extack, nla, 1967 "RTA_TTL_PROPAGATE can only be 0 or 1"); 1968 goto errout; 1969 } 1970 cfg->rc_ttl_propagate = ttl_propagate ? 1971 MPLS_TTL_PROP_ENABLED : 1972 MPLS_TTL_PROP_DISABLED; 1973 break; 1974 } 1975 default: 1976 NL_SET_ERR_MSG_ATTR(extack, nla, "Unknown attribute"); 1977 /* Unsupported attribute */ 1978 goto errout; 1979 } 1980 } 1981 1982 err = 0; 1983 errout: 1984 return err; 1985 } 1986 1987 static int mpls_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh, 1988 struct netlink_ext_ack *extack) 1989 { 1990 struct net *net = sock_net(skb->sk); 1991 struct mpls_route_config *cfg; 1992 int err; 1993 1994 cfg = kzalloc_obj(*cfg); 1995 if (!cfg) 1996 return -ENOMEM; 1997 1998 err = rtm_to_route_config(skb, nlh, cfg, extack); 1999 if (err < 0) 2000 goto out; 2001 2002 mutex_lock(&net->mpls.platform_mutex); 2003 err = mpls_route_del(cfg, extack); 2004 mutex_unlock(&net->mpls.platform_mutex); 2005 out: 2006 kfree(cfg); 2007 2008 return err; 2009 } 2010 2011 2012 static int mpls_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh, 2013 struct netlink_ext_ack *extack) 2014 { 2015 struct net *net = sock_net(skb->sk); 2016 struct mpls_route_config *cfg; 2017 int err; 2018 2019 cfg = kzalloc_obj(*cfg); 2020 if (!cfg) 2021 return -ENOMEM; 2022 2023 err = rtm_to_route_config(skb, nlh, cfg, extack); 2024 if (err < 0) 2025 goto out; 2026 2027 mutex_lock(&net->mpls.platform_mutex); 2028 err = mpls_route_add(cfg, extack); 2029 mutex_unlock(&net->mpls.platform_mutex); 2030 out: 2031 kfree(cfg); 2032 2033 return err; 2034 } 2035 2036 static int mpls_dump_route(struct sk_buff *skb, u32 portid, u32 seq, int event, 2037 u32 label, struct mpls_route *rt, int flags) 2038 { 2039 struct net_device *dev; 2040 struct nlmsghdr *nlh; 2041 struct rtmsg *rtm; 2042 2043 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*rtm), flags); 2044 if (nlh == NULL) 2045 return -EMSGSIZE; 2046 2047 rtm = nlmsg_data(nlh); 2048 rtm->rtm_family = AF_MPLS; 2049 rtm->rtm_dst_len = 20; 2050 rtm->rtm_src_len = 0; 2051 rtm->rtm_tos = 0; 2052 rtm->rtm_table = RT_TABLE_MAIN; 2053 rtm->rtm_protocol = rt->rt_protocol; 2054 rtm->rtm_scope = RT_SCOPE_UNIVERSE; 2055 rtm->rtm_type = RTN_UNICAST; 2056 rtm->rtm_flags = 0; 2057 2058 if (nla_put_labels(skb, RTA_DST, 1, &label)) 2059 goto nla_put_failure; 2060 2061 if (rt->rt_ttl_propagate != MPLS_TTL_PROP_DEFAULT) { 2062 bool ttl_propagate = 2063 rt->rt_ttl_propagate == MPLS_TTL_PROP_ENABLED; 2064 2065 if (nla_put_u8(skb, RTA_TTL_PROPAGATE, 2066 ttl_propagate)) 2067 goto nla_put_failure; 2068 } 2069 if (rt->rt_nhn == 1) { 2070 const struct mpls_nh *nh = rt->rt_nh; 2071 2072 if (nh->nh_labels && 2073 nla_put_labels(skb, RTA_NEWDST, nh->nh_labels, 2074 nh->nh_label)) 2075 goto nla_put_failure; 2076 if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC && 2077 nla_put_via(skb, nh->nh_via_table, mpls_nh_via(rt, nh), 2078 nh->nh_via_alen)) 2079 goto nla_put_failure; 2080 dev = nh->nh_dev; 2081 if (dev && nla_put_u32(skb, RTA_OIF, dev->ifindex)) 2082 goto nla_put_failure; 2083 if (nh->nh_flags & RTNH_F_LINKDOWN) 2084 rtm->rtm_flags |= RTNH_F_LINKDOWN; 2085 if (nh->nh_flags & RTNH_F_DEAD) 2086 rtm->rtm_flags |= RTNH_F_DEAD; 2087 } else { 2088 struct rtnexthop *rtnh; 2089 struct nlattr *mp; 2090 u8 linkdown = 0; 2091 u8 dead = 0; 2092 2093 mp = nla_nest_start_noflag(skb, RTA_MULTIPATH); 2094 if (!mp) 2095 goto nla_put_failure; 2096 2097 for_nexthops(rt) { 2098 dev = nh->nh_dev; 2099 if (!dev) 2100 continue; 2101 2102 rtnh = nla_reserve_nohdr(skb, sizeof(*rtnh)); 2103 if (!rtnh) 2104 goto nla_put_failure; 2105 2106 rtnh->rtnh_ifindex = dev->ifindex; 2107 if (nh->nh_flags & RTNH_F_LINKDOWN) { 2108 rtnh->rtnh_flags |= RTNH_F_LINKDOWN; 2109 linkdown++; 2110 } 2111 if (nh->nh_flags & RTNH_F_DEAD) { 2112 rtnh->rtnh_flags |= RTNH_F_DEAD; 2113 dead++; 2114 } 2115 2116 if (nh->nh_labels && nla_put_labels(skb, RTA_NEWDST, 2117 nh->nh_labels, 2118 nh->nh_label)) 2119 goto nla_put_failure; 2120 if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC && 2121 nla_put_via(skb, nh->nh_via_table, 2122 mpls_nh_via(rt, nh), 2123 nh->nh_via_alen)) 2124 goto nla_put_failure; 2125 2126 /* length of rtnetlink header + attributes */ 2127 rtnh->rtnh_len = nlmsg_get_pos(skb) - (void *)rtnh; 2128 } endfor_nexthops(rt); 2129 2130 if (linkdown == rt->rt_nhn) 2131 rtm->rtm_flags |= RTNH_F_LINKDOWN; 2132 if (dead == rt->rt_nhn) 2133 rtm->rtm_flags |= RTNH_F_DEAD; 2134 2135 nla_nest_end(skb, mp); 2136 } 2137 2138 nlmsg_end(skb, nlh); 2139 return 0; 2140 2141 nla_put_failure: 2142 nlmsg_cancel(skb, nlh); 2143 return -EMSGSIZE; 2144 } 2145 2146 #if IS_ENABLED(CONFIG_INET) 2147 static int mpls_valid_fib_dump_req(struct net *net, const struct nlmsghdr *nlh, 2148 struct fib_dump_filter *filter, 2149 struct netlink_callback *cb) 2150 { 2151 return ip_valid_fib_dump_req(net, nlh, filter, cb); 2152 } 2153 #else 2154 static int mpls_valid_fib_dump_req(struct net *net, const struct nlmsghdr *nlh, 2155 struct fib_dump_filter *filter, 2156 struct netlink_callback *cb) 2157 { 2158 struct netlink_ext_ack *extack = cb->extack; 2159 struct nlattr *tb[RTA_MAX + 1]; 2160 struct rtmsg *rtm; 2161 int err, i; 2162 2163 rtm = nlmsg_payload(nlh, sizeof(*rtm)); 2164 if (!rtm) { 2165 NL_SET_ERR_MSG_MOD(extack, "Invalid header for FIB dump request"); 2166 return -EINVAL; 2167 } 2168 2169 if (rtm->rtm_dst_len || rtm->rtm_src_len || rtm->rtm_tos || 2170 rtm->rtm_table || rtm->rtm_scope || rtm->rtm_type || 2171 rtm->rtm_flags) { 2172 NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for FIB dump request"); 2173 return -EINVAL; 2174 } 2175 2176 if (rtm->rtm_protocol) { 2177 filter->protocol = rtm->rtm_protocol; 2178 filter->filter_set = 1; 2179 cb->answer_flags = NLM_F_DUMP_FILTERED; 2180 } 2181 2182 err = nlmsg_parse_deprecated_strict(nlh, sizeof(*rtm), tb, RTA_MAX, 2183 rtm_mpls_policy, extack); 2184 if (err < 0) 2185 return err; 2186 2187 for (i = 0; i <= RTA_MAX; ++i) { 2188 int ifindex; 2189 2190 if (i == RTA_OIF) { 2191 if (!tb[i]) 2192 continue; 2193 2194 ifindex = nla_get_u32(tb[i]); 2195 filter->dev = dev_get_by_index_rcu(net, ifindex); 2196 if (!filter->dev) 2197 return -ENODEV; 2198 filter->filter_set = 1; 2199 } else if (tb[i]) { 2200 NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in dump request"); 2201 return -EINVAL; 2202 } 2203 } 2204 2205 return 0; 2206 } 2207 #endif 2208 2209 static bool mpls_rt_uses_dev(struct mpls_route *rt, 2210 const struct net_device *dev) 2211 { 2212 if (rt->rt_nhn == 1) { 2213 struct mpls_nh *nh = rt->rt_nh; 2214 2215 if (nh->nh_dev == dev) 2216 return true; 2217 } else { 2218 for_nexthops(rt) { 2219 if (nh->nh_dev == dev) 2220 return true; 2221 } endfor_nexthops(rt); 2222 } 2223 2224 return false; 2225 } 2226 2227 static int mpls_dump_routes(struct sk_buff *skb, struct netlink_callback *cb) 2228 { 2229 struct mpls_route __rcu **platform_label; 2230 const struct nlmsghdr *nlh = cb->nlh; 2231 struct net *net = sock_net(skb->sk); 2232 struct fib_dump_filter filter = {}; 2233 unsigned int flags = NLM_F_MULTI; 2234 size_t platform_labels; 2235 unsigned int index; 2236 int err; 2237 2238 rcu_read_lock(); 2239 2240 if (cb->strict_check) { 2241 err = mpls_valid_fib_dump_req(net, nlh, &filter, cb); 2242 if (err < 0) 2243 goto err; 2244 2245 /* for MPLS, there is only 1 table with fixed type and flags. 2246 * If either are set in the filter then return nothing. 2247 */ 2248 if ((filter.table_id && filter.table_id != RT_TABLE_MAIN) || 2249 (filter.rt_type && filter.rt_type != RTN_UNICAST) || 2250 filter.flags) 2251 goto unlock; 2252 } 2253 2254 index = cb->args[0]; 2255 if (index < MPLS_LABEL_FIRST_UNRESERVED) 2256 index = MPLS_LABEL_FIRST_UNRESERVED; 2257 2258 platform_label = mpls_platform_label_rcu(net, &platform_labels); 2259 2260 if (filter.filter_set) 2261 flags |= NLM_F_DUMP_FILTERED; 2262 2263 for (; index < platform_labels; index++) { 2264 struct mpls_route *rt; 2265 2266 rt = rcu_dereference(platform_label[index]); 2267 if (!rt) 2268 continue; 2269 2270 if ((filter.dev && !mpls_rt_uses_dev(rt, filter.dev)) || 2271 (filter.protocol && rt->rt_protocol != filter.protocol)) 2272 continue; 2273 2274 if (mpls_dump_route(skb, NETLINK_CB(cb->skb).portid, 2275 cb->nlh->nlmsg_seq, RTM_NEWROUTE, 2276 index, rt, flags) < 0) 2277 break; 2278 } 2279 cb->args[0] = index; 2280 2281 unlock: 2282 rcu_read_unlock(); 2283 return skb->len; 2284 2285 err: 2286 rcu_read_unlock(); 2287 return err; 2288 } 2289 2290 static inline size_t lfib_nlmsg_size(struct mpls_route *rt) 2291 { 2292 size_t payload = 2293 NLMSG_ALIGN(sizeof(struct rtmsg)) 2294 + nla_total_size(4) /* RTA_DST */ 2295 + nla_total_size(1); /* RTA_TTL_PROPAGATE */ 2296 2297 if (rt->rt_nhn == 1) { 2298 struct mpls_nh *nh = rt->rt_nh; 2299 2300 if (nh->nh_dev) 2301 payload += nla_total_size(4); /* RTA_OIF */ 2302 if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC) /* RTA_VIA */ 2303 payload += nla_total_size(2 + nh->nh_via_alen); 2304 if (nh->nh_labels) /* RTA_NEWDST */ 2305 payload += nla_total_size(nh->nh_labels * 4); 2306 } else { 2307 /* each nexthop is packed in an attribute */ 2308 size_t nhsize = 0; 2309 2310 for_nexthops(rt) { 2311 if (!nh->nh_dev) 2312 continue; 2313 nhsize += nla_total_size(sizeof(struct rtnexthop)); 2314 /* RTA_VIA */ 2315 if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC) 2316 nhsize += nla_total_size(2 + nh->nh_via_alen); 2317 if (nh->nh_labels) 2318 nhsize += nla_total_size(nh->nh_labels * 4); 2319 } endfor_nexthops(rt); 2320 /* nested attribute */ 2321 payload += nla_total_size(nhsize); 2322 } 2323 2324 return payload; 2325 } 2326 2327 static void rtmsg_lfib(int event, u32 label, struct mpls_route *rt, 2328 struct nlmsghdr *nlh, struct net *net, u32 portid, 2329 unsigned int nlm_flags) 2330 { 2331 struct sk_buff *skb; 2332 u32 seq = nlh ? nlh->nlmsg_seq : 0; 2333 int err = -ENOBUFS; 2334 2335 skb = nlmsg_new(lfib_nlmsg_size(rt), GFP_KERNEL); 2336 if (skb == NULL) 2337 goto errout; 2338 2339 err = mpls_dump_route(skb, portid, seq, event, label, rt, nlm_flags); 2340 if (err < 0) { 2341 /* -EMSGSIZE implies BUG in lfib_nlmsg_size */ 2342 WARN_ON(err == -EMSGSIZE); 2343 kfree_skb(skb); 2344 goto errout; 2345 } 2346 rtnl_notify(skb, net, portid, RTNLGRP_MPLS_ROUTE, nlh, GFP_KERNEL); 2347 2348 return; 2349 errout: 2350 rtnl_set_sk_err(net, RTNLGRP_MPLS_ROUTE, err); 2351 } 2352 2353 static int mpls_valid_getroute_req(struct sk_buff *skb, 2354 const struct nlmsghdr *nlh, 2355 struct nlattr **tb, 2356 struct netlink_ext_ack *extack) 2357 { 2358 struct rtmsg *rtm; 2359 int i, err; 2360 2361 rtm = nlmsg_payload(nlh, sizeof(*rtm)); 2362 if (!rtm) { 2363 NL_SET_ERR_MSG_MOD(extack, 2364 "Invalid header for get route request"); 2365 return -EINVAL; 2366 } 2367 2368 if (!netlink_strict_get_check(skb)) 2369 return nlmsg_parse_deprecated(nlh, sizeof(*rtm), tb, RTA_MAX, 2370 rtm_mpls_policy, extack); 2371 2372 if ((rtm->rtm_dst_len && rtm->rtm_dst_len != 20) || 2373 rtm->rtm_src_len || rtm->rtm_tos || rtm->rtm_table || 2374 rtm->rtm_protocol || rtm->rtm_scope || rtm->rtm_type) { 2375 NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for get route request"); 2376 return -EINVAL; 2377 } 2378 if (rtm->rtm_flags & ~RTM_F_FIB_MATCH) { 2379 NL_SET_ERR_MSG_MOD(extack, 2380 "Invalid flags for get route request"); 2381 return -EINVAL; 2382 } 2383 2384 err = nlmsg_parse_deprecated_strict(nlh, sizeof(*rtm), tb, RTA_MAX, 2385 rtm_mpls_policy, extack); 2386 if (err) 2387 return err; 2388 2389 if ((tb[RTA_DST] || tb[RTA_NEWDST]) && !rtm->rtm_dst_len) { 2390 NL_SET_ERR_MSG_MOD(extack, "rtm_dst_len must be 20 for MPLS"); 2391 return -EINVAL; 2392 } 2393 2394 for (i = 0; i <= RTA_MAX; i++) { 2395 if (!tb[i]) 2396 continue; 2397 2398 switch (i) { 2399 case RTA_DST: 2400 case RTA_NEWDST: 2401 break; 2402 default: 2403 NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in get route request"); 2404 return -EINVAL; 2405 } 2406 } 2407 2408 return 0; 2409 } 2410 2411 static int mpls_getroute(struct sk_buff *in_skb, struct nlmsghdr *in_nlh, 2412 struct netlink_ext_ack *extack) 2413 { 2414 struct net *net = sock_net(in_skb->sk); 2415 u32 portid = NETLINK_CB(in_skb).portid; 2416 u32 in_label = LABEL_NOT_SPECIFIED; 2417 struct nlattr *tb[RTA_MAX + 1]; 2418 struct mpls_route *rt = NULL; 2419 u32 labels[MAX_NEW_LABELS]; 2420 struct mpls_shim_hdr *hdr; 2421 unsigned int hdr_size = 0; 2422 const struct mpls_nh *nh; 2423 struct net_device *dev; 2424 struct rtmsg *rtm, *r; 2425 struct nlmsghdr *nlh; 2426 struct sk_buff *skb; 2427 u8 n_labels; 2428 int err; 2429 2430 mutex_lock(&net->mpls.platform_mutex); 2431 2432 err = mpls_valid_getroute_req(in_skb, in_nlh, tb, extack); 2433 if (err < 0) 2434 goto errout; 2435 2436 rtm = nlmsg_data(in_nlh); 2437 2438 if (tb[RTA_DST]) { 2439 u8 label_count; 2440 2441 if (nla_get_labels(tb[RTA_DST], 1, &label_count, 2442 &in_label, extack)) { 2443 err = -EINVAL; 2444 goto errout; 2445 } 2446 2447 if (!mpls_label_ok(net, &in_label, extack)) { 2448 err = -EINVAL; 2449 goto errout; 2450 } 2451 } 2452 2453 if (in_label < net->mpls.platform_labels) 2454 rt = mpls_route_input(net, in_label); 2455 if (!rt) { 2456 err = -ENETUNREACH; 2457 goto errout; 2458 } 2459 2460 if (rtm->rtm_flags & RTM_F_FIB_MATCH) { 2461 skb = nlmsg_new(lfib_nlmsg_size(rt), GFP_KERNEL); 2462 if (!skb) { 2463 err = -ENOBUFS; 2464 goto errout; 2465 } 2466 2467 err = mpls_dump_route(skb, portid, in_nlh->nlmsg_seq, 2468 RTM_NEWROUTE, in_label, rt, 0); 2469 if (err < 0) { 2470 /* -EMSGSIZE implies BUG in lfib_nlmsg_size */ 2471 WARN_ON(err == -EMSGSIZE); 2472 goto errout_free; 2473 } 2474 2475 err = rtnl_unicast(skb, net, portid); 2476 goto errout; 2477 } 2478 2479 if (tb[RTA_NEWDST]) { 2480 if (nla_get_labels(tb[RTA_NEWDST], MAX_NEW_LABELS, &n_labels, 2481 labels, extack) != 0) { 2482 err = -EINVAL; 2483 goto errout; 2484 } 2485 2486 hdr_size = n_labels * sizeof(struct mpls_shim_hdr); 2487 } 2488 2489 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); 2490 if (!skb) { 2491 err = -ENOBUFS; 2492 goto errout; 2493 } 2494 2495 skb->protocol = htons(ETH_P_MPLS_UC); 2496 2497 if (hdr_size) { 2498 bool bos; 2499 int i; 2500 2501 if (skb_cow(skb, hdr_size)) { 2502 err = -ENOBUFS; 2503 goto errout_free; 2504 } 2505 2506 skb_reserve(skb, hdr_size); 2507 skb_push(skb, hdr_size); 2508 skb_reset_network_header(skb); 2509 2510 /* Push new labels */ 2511 hdr = mpls_hdr(skb); 2512 bos = true; 2513 for (i = n_labels - 1; i >= 0; i--) { 2514 hdr[i] = mpls_entry_encode(labels[i], 2515 1, 0, bos); 2516 bos = false; 2517 } 2518 } 2519 2520 nh = mpls_select_multipath(rt, skb); 2521 if (!nh) { 2522 err = -ENETUNREACH; 2523 goto errout_free; 2524 } 2525 2526 if (hdr_size) { 2527 skb_pull(skb, hdr_size); 2528 skb_reset_network_header(skb); 2529 } 2530 2531 nlh = nlmsg_put(skb, portid, in_nlh->nlmsg_seq, 2532 RTM_NEWROUTE, sizeof(*r), 0); 2533 if (!nlh) { 2534 err = -EMSGSIZE; 2535 goto errout_free; 2536 } 2537 2538 r = nlmsg_data(nlh); 2539 r->rtm_family = AF_MPLS; 2540 r->rtm_dst_len = 20; 2541 r->rtm_src_len = 0; 2542 r->rtm_tos = 0; 2543 r->rtm_table = RT_TABLE_MAIN; 2544 r->rtm_type = RTN_UNICAST; 2545 r->rtm_scope = RT_SCOPE_UNIVERSE; 2546 r->rtm_protocol = rt->rt_protocol; 2547 r->rtm_flags = 0; 2548 2549 if (nla_put_labels(skb, RTA_DST, 1, &in_label)) 2550 goto nla_put_failure; 2551 2552 if (nh->nh_labels && 2553 nla_put_labels(skb, RTA_NEWDST, nh->nh_labels, 2554 nh->nh_label)) 2555 goto nla_put_failure; 2556 2557 if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC && 2558 nla_put_via(skb, nh->nh_via_table, mpls_nh_via(rt, nh), 2559 nh->nh_via_alen)) 2560 goto nla_put_failure; 2561 dev = nh->nh_dev; 2562 if (dev && nla_put_u32(skb, RTA_OIF, dev->ifindex)) 2563 goto nla_put_failure; 2564 2565 nlmsg_end(skb, nlh); 2566 2567 err = rtnl_unicast(skb, net, portid); 2568 errout: 2569 mutex_unlock(&net->mpls.platform_mutex); 2570 return err; 2571 2572 nla_put_failure: 2573 nlmsg_cancel(skb, nlh); 2574 err = -EMSGSIZE; 2575 errout_free: 2576 mutex_unlock(&net->mpls.platform_mutex); 2577 kfree_skb(skb); 2578 return err; 2579 } 2580 2581 static int resize_platform_label_table(struct net *net, size_t limit) 2582 { 2583 size_t size = sizeof(struct mpls_route *) * limit; 2584 size_t old_limit; 2585 size_t cp_size; 2586 struct mpls_route __rcu **labels = NULL, **old; 2587 struct mpls_route *rt0 = NULL, *rt2 = NULL; 2588 unsigned index; 2589 2590 if (size) { 2591 labels = kvzalloc(size, GFP_KERNEL); 2592 if (!labels) 2593 goto nolabels; 2594 } 2595 2596 /* In case the predefined labels need to be populated */ 2597 if (limit > MPLS_LABEL_IPV4NULL) { 2598 struct net_device *lo = net->loopback_dev; 2599 2600 rt0 = mpls_rt_alloc(1, lo->addr_len, 0); 2601 if (IS_ERR(rt0)) 2602 goto nort0; 2603 2604 rt0->rt_nh->nh_dev = lo; 2605 netdev_hold(lo, &rt0->rt_nh->nh_dev_tracker, GFP_KERNEL); 2606 rt0->rt_protocol = RTPROT_KERNEL; 2607 rt0->rt_payload_type = MPT_IPV4; 2608 rt0->rt_ttl_propagate = MPLS_TTL_PROP_DEFAULT; 2609 rt0->rt_nh->nh_via_table = NEIGH_LINK_TABLE; 2610 rt0->rt_nh->nh_via_alen = lo->addr_len; 2611 memcpy(__mpls_nh_via(rt0, rt0->rt_nh), lo->dev_addr, 2612 lo->addr_len); 2613 } 2614 if (limit > MPLS_LABEL_IPV6NULL) { 2615 struct net_device *lo = net->loopback_dev; 2616 2617 rt2 = mpls_rt_alloc(1, lo->addr_len, 0); 2618 if (IS_ERR(rt2)) 2619 goto nort2; 2620 2621 rt2->rt_nh->nh_dev = lo; 2622 netdev_hold(lo, &rt2->rt_nh->nh_dev_tracker, GFP_KERNEL); 2623 rt2->rt_protocol = RTPROT_KERNEL; 2624 rt2->rt_payload_type = MPT_IPV6; 2625 rt2->rt_ttl_propagate = MPLS_TTL_PROP_DEFAULT; 2626 rt2->rt_nh->nh_via_table = NEIGH_LINK_TABLE; 2627 rt2->rt_nh->nh_via_alen = lo->addr_len; 2628 memcpy(__mpls_nh_via(rt2, rt2->rt_nh), lo->dev_addr, 2629 lo->addr_len); 2630 } 2631 2632 mutex_lock(&net->mpls.platform_mutex); 2633 2634 /* Remember the original table */ 2635 old = mpls_dereference(net, net->mpls.platform_label); 2636 old_limit = net->mpls.platform_labels; 2637 2638 /* Free any labels beyond the new table */ 2639 for (index = limit; index < old_limit; index++) 2640 mpls_route_update(net, index, NULL, NULL); 2641 2642 /* Copy over the old labels */ 2643 cp_size = size; 2644 if (old_limit < limit) 2645 cp_size = old_limit * sizeof(struct mpls_route *); 2646 2647 memcpy(labels, old, cp_size); 2648 2649 /* If needed set the predefined labels */ 2650 if ((old_limit <= MPLS_LABEL_IPV6NULL) && 2651 (limit > MPLS_LABEL_IPV6NULL)) { 2652 RCU_INIT_POINTER(labels[MPLS_LABEL_IPV6NULL], rt2); 2653 rt2 = NULL; 2654 } 2655 2656 if ((old_limit <= MPLS_LABEL_IPV4NULL) && 2657 (limit > MPLS_LABEL_IPV4NULL)) { 2658 RCU_INIT_POINTER(labels[MPLS_LABEL_IPV4NULL], rt0); 2659 rt0 = NULL; 2660 } 2661 2662 /* Update the global pointers */ 2663 local_bh_disable(); 2664 write_seqcount_begin(&net->mpls.platform_label_seq); 2665 net->mpls.platform_labels = limit; 2666 rcu_assign_pointer(net->mpls.platform_label, labels); 2667 write_seqcount_end(&net->mpls.platform_label_seq); 2668 local_bh_enable(); 2669 2670 mutex_unlock(&net->mpls.platform_mutex); 2671 2672 mpls_rt_free(rt2); 2673 mpls_rt_free(rt0); 2674 2675 if (old) { 2676 synchronize_rcu(); 2677 kvfree(old); 2678 } 2679 return 0; 2680 2681 nort2: 2682 mpls_rt_free(rt0); 2683 nort0: 2684 kvfree(labels); 2685 nolabels: 2686 return -ENOMEM; 2687 } 2688 2689 static int mpls_platform_labels(const struct ctl_table *table, int write, 2690 void *buffer, size_t *lenp, loff_t *ppos) 2691 { 2692 struct net *net = table->data; 2693 int platform_labels = net->mpls.platform_labels; 2694 int ret; 2695 struct ctl_table tmp = { 2696 .procname = table->procname, 2697 .data = &platform_labels, 2698 .maxlen = sizeof(int), 2699 .mode = table->mode, 2700 .extra1 = SYSCTL_ZERO, 2701 .extra2 = &label_limit, 2702 }; 2703 2704 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos); 2705 2706 if (write && ret == 0) 2707 ret = resize_platform_label_table(net, platform_labels); 2708 2709 return ret; 2710 } 2711 2712 #define MPLS_NS_SYSCTL_OFFSET(field) \ 2713 (&((struct net *)0)->field) 2714 2715 static const struct ctl_table mpls_table[] = { 2716 { 2717 .procname = "platform_labels", 2718 .data = NULL, 2719 .maxlen = sizeof(int), 2720 .mode = 0644, 2721 .proc_handler = mpls_platform_labels, 2722 }, 2723 { 2724 .procname = "ip_ttl_propagate", 2725 .data = MPLS_NS_SYSCTL_OFFSET(mpls.ip_ttl_propagate), 2726 .maxlen = sizeof(int), 2727 .mode = 0644, 2728 .proc_handler = proc_dointvec_minmax, 2729 .extra1 = SYSCTL_ZERO, 2730 .extra2 = SYSCTL_ONE, 2731 }, 2732 { 2733 .procname = "default_ttl", 2734 .data = MPLS_NS_SYSCTL_OFFSET(mpls.default_ttl), 2735 .maxlen = sizeof(int), 2736 .mode = 0644, 2737 .proc_handler = proc_dointvec_minmax, 2738 .extra1 = SYSCTL_ONE, 2739 .extra2 = &ttl_max, 2740 }, 2741 }; 2742 2743 static __net_init int mpls_net_init(struct net *net) 2744 { 2745 size_t table_size = ARRAY_SIZE(mpls_table); 2746 struct ctl_table *table; 2747 int i; 2748 2749 mutex_init(&net->mpls.platform_mutex); 2750 seqcount_mutex_init(&net->mpls.platform_label_seq, &net->mpls.platform_mutex); 2751 2752 net->mpls.platform_labels = 0; 2753 net->mpls.platform_label = NULL; 2754 net->mpls.ip_ttl_propagate = 1; 2755 net->mpls.default_ttl = 255; 2756 2757 table = kmemdup(mpls_table, sizeof(mpls_table), GFP_KERNEL); 2758 if (table == NULL) 2759 return -ENOMEM; 2760 2761 /* Table data contains only offsets relative to the base of 2762 * the mdev at this point, so make them absolute. 2763 */ 2764 for (i = 0; i < table_size; i++) 2765 table[i].data = (char *)net + (uintptr_t)table[i].data; 2766 2767 net->mpls.ctl = register_net_sysctl_sz(net, "net/mpls", table, 2768 table_size); 2769 if (net->mpls.ctl == NULL) { 2770 kfree(table); 2771 return -ENOMEM; 2772 } 2773 2774 return 0; 2775 } 2776 2777 static __net_exit void mpls_net_exit(struct net *net) 2778 { 2779 struct mpls_route __rcu **platform_label; 2780 size_t platform_labels; 2781 const struct ctl_table *table; 2782 unsigned int index; 2783 2784 table = net->mpls.ctl->ctl_table_arg; 2785 unregister_net_sysctl_table(net->mpls.ctl); 2786 kfree(table); 2787 2788 /* An rcu grace period has passed since there was a device in 2789 * the network namespace (and thus the last in flight packet) 2790 * left this network namespace. This is because 2791 * unregister_netdevice_many and netdev_run_todo has completed 2792 * for each network device that was in this network namespace. 2793 * 2794 * As such no additional rcu synchronization is necessary when 2795 * freeing the platform_label table. 2796 */ 2797 mutex_lock(&net->mpls.platform_mutex); 2798 2799 platform_label = mpls_dereference(net, net->mpls.platform_label); 2800 platform_labels = net->mpls.platform_labels; 2801 2802 for (index = 0; index < platform_labels; index++) { 2803 struct mpls_route *rt; 2804 2805 rt = mpls_dereference(net, platform_label[index]); 2806 mpls_notify_route(net, index, rt, NULL, NULL); 2807 mpls_rt_free(rt); 2808 } 2809 2810 mutex_unlock(&net->mpls.platform_mutex); 2811 2812 kvfree(platform_label); 2813 } 2814 2815 static struct pernet_operations mpls_net_ops = { 2816 .init = mpls_net_init, 2817 .exit = mpls_net_exit, 2818 }; 2819 2820 static struct rtnl_af_ops mpls_af_ops __read_mostly = { 2821 .family = AF_MPLS, 2822 .fill_stats_af = mpls_fill_stats_af, 2823 .get_stats_af_size = mpls_get_stats_af_size, 2824 }; 2825 2826 static const struct rtnl_msg_handler mpls_rtnl_msg_handlers[] __initdata_or_module = { 2827 {THIS_MODULE, PF_MPLS, RTM_NEWROUTE, mpls_rtm_newroute, NULL, 2828 RTNL_FLAG_DOIT_UNLOCKED}, 2829 {THIS_MODULE, PF_MPLS, RTM_DELROUTE, mpls_rtm_delroute, NULL, 2830 RTNL_FLAG_DOIT_UNLOCKED}, 2831 {THIS_MODULE, PF_MPLS, RTM_GETROUTE, mpls_getroute, mpls_dump_routes, 2832 RTNL_FLAG_DOIT_UNLOCKED | RTNL_FLAG_DUMP_UNLOCKED}, 2833 {THIS_MODULE, PF_MPLS, RTM_GETNETCONF, 2834 mpls_netconf_get_devconf, mpls_netconf_dump_devconf, 2835 RTNL_FLAG_DOIT_UNLOCKED | RTNL_FLAG_DUMP_UNLOCKED}, 2836 }; 2837 2838 static int __init mpls_init(void) 2839 { 2840 int err; 2841 2842 BUILD_BUG_ON(sizeof(struct mpls_shim_hdr) != 4); 2843 2844 err = register_pernet_subsys(&mpls_net_ops); 2845 if (err) 2846 goto out; 2847 2848 err = register_netdevice_notifier(&mpls_dev_notifier); 2849 if (err) 2850 goto out_unregister_pernet; 2851 2852 dev_add_pack(&mpls_packet_type); 2853 2854 err = rtnl_af_register(&mpls_af_ops); 2855 if (err) 2856 goto out_unregister_dev_type; 2857 2858 err = rtnl_register_many(mpls_rtnl_msg_handlers); 2859 if (err) 2860 goto out_unregister_rtnl_af; 2861 2862 err = ipgre_tunnel_encap_add_mpls_ops(); 2863 if (err) { 2864 pr_err("Can't add mpls over gre tunnel ops\n"); 2865 goto out_unregister_rtnl; 2866 } 2867 2868 err = 0; 2869 out: 2870 return err; 2871 2872 out_unregister_rtnl: 2873 rtnl_unregister_many(mpls_rtnl_msg_handlers); 2874 out_unregister_rtnl_af: 2875 rtnl_af_unregister(&mpls_af_ops); 2876 out_unregister_dev_type: 2877 dev_remove_pack(&mpls_packet_type); 2878 unregister_netdevice_notifier(&mpls_dev_notifier); 2879 out_unregister_pernet: 2880 unregister_pernet_subsys(&mpls_net_ops); 2881 goto out; 2882 } 2883 module_init(mpls_init); 2884 2885 static void __exit mpls_exit(void) 2886 { 2887 rtnl_unregister_all(PF_MPLS); 2888 rtnl_af_unregister(&mpls_af_ops); 2889 dev_remove_pack(&mpls_packet_type); 2890 unregister_netdevice_notifier(&mpls_dev_notifier); 2891 unregister_pernet_subsys(&mpls_net_ops); 2892 ipgre_tunnel_encap_del_mpls_ops(); 2893 } 2894 module_exit(mpls_exit); 2895 2896 MODULE_DESCRIPTION("MultiProtocol Label Switching"); 2897 MODULE_LICENSE("GPL v2"); 2898 MODULE_ALIAS_NETPROTO(PF_MPLS); 2899