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