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 struct netlink_ext_ack *extack) 1115 { 1116 struct net *net = sock_net(in_skb->sk); 1117 struct nlattr *tb[NETCONFA_MAX + 1]; 1118 struct netconfmsg *ncm; 1119 struct net_device *dev; 1120 struct mpls_dev *mdev; 1121 struct sk_buff *skb; 1122 int ifindex; 1123 int err; 1124 1125 err = nlmsg_parse(nlh, sizeof(*ncm), tb, NETCONFA_MAX, 1126 devconf_mpls_policy, NULL); 1127 if (err < 0) 1128 goto errout; 1129 1130 err = -EINVAL; 1131 if (!tb[NETCONFA_IFINDEX]) 1132 goto errout; 1133 1134 ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]); 1135 dev = __dev_get_by_index(net, ifindex); 1136 if (!dev) 1137 goto errout; 1138 1139 mdev = mpls_dev_get(dev); 1140 if (!mdev) 1141 goto errout; 1142 1143 err = -ENOBUFS; 1144 skb = nlmsg_new(mpls_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL); 1145 if (!skb) 1146 goto errout; 1147 1148 err = mpls_netconf_fill_devconf(skb, mdev, 1149 NETLINK_CB(in_skb).portid, 1150 nlh->nlmsg_seq, RTM_NEWNETCONF, 0, 1151 NETCONFA_ALL); 1152 if (err < 0) { 1153 /* -EMSGSIZE implies BUG in mpls_netconf_msgsize_devconf() */ 1154 WARN_ON(err == -EMSGSIZE); 1155 kfree_skb(skb); 1156 goto errout; 1157 } 1158 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid); 1159 errout: 1160 return err; 1161 } 1162 1163 static int mpls_netconf_dump_devconf(struct sk_buff *skb, 1164 struct netlink_callback *cb) 1165 { 1166 struct net *net = sock_net(skb->sk); 1167 struct hlist_head *head; 1168 struct net_device *dev; 1169 struct mpls_dev *mdev; 1170 int idx, s_idx; 1171 int h, s_h; 1172 1173 s_h = cb->args[0]; 1174 s_idx = idx = cb->args[1]; 1175 1176 for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) { 1177 idx = 0; 1178 head = &net->dev_index_head[h]; 1179 rcu_read_lock(); 1180 cb->seq = net->dev_base_seq; 1181 hlist_for_each_entry_rcu(dev, head, index_hlist) { 1182 if (idx < s_idx) 1183 goto cont; 1184 mdev = mpls_dev_get(dev); 1185 if (!mdev) 1186 goto cont; 1187 if (mpls_netconf_fill_devconf(skb, mdev, 1188 NETLINK_CB(cb->skb).portid, 1189 cb->nlh->nlmsg_seq, 1190 RTM_NEWNETCONF, 1191 NLM_F_MULTI, 1192 NETCONFA_ALL) < 0) { 1193 rcu_read_unlock(); 1194 goto done; 1195 } 1196 nl_dump_check_consistent(cb, nlmsg_hdr(skb)); 1197 cont: 1198 idx++; 1199 } 1200 rcu_read_unlock(); 1201 } 1202 done: 1203 cb->args[0] = h; 1204 cb->args[1] = idx; 1205 1206 return skb->len; 1207 } 1208 1209 #define MPLS_PERDEV_SYSCTL_OFFSET(field) \ 1210 (&((struct mpls_dev *)0)->field) 1211 1212 static int mpls_conf_proc(struct ctl_table *ctl, int write, 1213 void __user *buffer, 1214 size_t *lenp, loff_t *ppos) 1215 { 1216 int oval = *(int *)ctl->data; 1217 int ret = proc_dointvec(ctl, write, buffer, lenp, ppos); 1218 1219 if (write) { 1220 struct mpls_dev *mdev = ctl->extra1; 1221 int i = (int *)ctl->data - (int *)mdev; 1222 struct net *net = ctl->extra2; 1223 int val = *(int *)ctl->data; 1224 1225 if (i == offsetof(struct mpls_dev, input_enabled) && 1226 val != oval) { 1227 mpls_netconf_notify_devconf(net, RTM_NEWNETCONF, 1228 NETCONFA_INPUT, mdev); 1229 } 1230 } 1231 1232 return ret; 1233 } 1234 1235 static const struct ctl_table mpls_dev_table[] = { 1236 { 1237 .procname = "input", 1238 .maxlen = sizeof(int), 1239 .mode = 0644, 1240 .proc_handler = mpls_conf_proc, 1241 .data = MPLS_PERDEV_SYSCTL_OFFSET(input_enabled), 1242 }, 1243 { } 1244 }; 1245 1246 static int mpls_dev_sysctl_register(struct net_device *dev, 1247 struct mpls_dev *mdev) 1248 { 1249 char path[sizeof("net/mpls/conf/") + IFNAMSIZ]; 1250 struct net *net = dev_net(dev); 1251 struct ctl_table *table; 1252 int i; 1253 1254 table = kmemdup(&mpls_dev_table, sizeof(mpls_dev_table), GFP_KERNEL); 1255 if (!table) 1256 goto out; 1257 1258 /* Table data contains only offsets relative to the base of 1259 * the mdev at this point, so make them absolute. 1260 */ 1261 for (i = 0; i < ARRAY_SIZE(mpls_dev_table); i++) { 1262 table[i].data = (char *)mdev + (uintptr_t)table[i].data; 1263 table[i].extra1 = mdev; 1264 table[i].extra2 = net; 1265 } 1266 1267 snprintf(path, sizeof(path), "net/mpls/conf/%s", dev->name); 1268 1269 mdev->sysctl = register_net_sysctl(net, path, table); 1270 if (!mdev->sysctl) 1271 goto free; 1272 1273 mpls_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL, mdev); 1274 return 0; 1275 1276 free: 1277 kfree(table); 1278 out: 1279 return -ENOBUFS; 1280 } 1281 1282 static void mpls_dev_sysctl_unregister(struct net_device *dev, 1283 struct mpls_dev *mdev) 1284 { 1285 struct net *net = dev_net(dev); 1286 struct ctl_table *table; 1287 1288 table = mdev->sysctl->ctl_table_arg; 1289 unregister_net_sysctl_table(mdev->sysctl); 1290 kfree(table); 1291 1292 mpls_netconf_notify_devconf(net, RTM_DELNETCONF, 0, mdev); 1293 } 1294 1295 static struct mpls_dev *mpls_add_dev(struct net_device *dev) 1296 { 1297 struct mpls_dev *mdev; 1298 int err = -ENOMEM; 1299 int i; 1300 1301 ASSERT_RTNL(); 1302 1303 mdev = kzalloc(sizeof(*mdev), GFP_KERNEL); 1304 if (!mdev) 1305 return ERR_PTR(err); 1306 1307 mdev->stats = alloc_percpu(struct mpls_pcpu_stats); 1308 if (!mdev->stats) 1309 goto free; 1310 1311 for_each_possible_cpu(i) { 1312 struct mpls_pcpu_stats *mpls_stats; 1313 1314 mpls_stats = per_cpu_ptr(mdev->stats, i); 1315 u64_stats_init(&mpls_stats->syncp); 1316 } 1317 1318 mdev->dev = dev; 1319 1320 err = mpls_dev_sysctl_register(dev, mdev); 1321 if (err) 1322 goto free; 1323 1324 rcu_assign_pointer(dev->mpls_ptr, mdev); 1325 1326 return mdev; 1327 1328 free: 1329 free_percpu(mdev->stats); 1330 kfree(mdev); 1331 return ERR_PTR(err); 1332 } 1333 1334 static void mpls_dev_destroy_rcu(struct rcu_head *head) 1335 { 1336 struct mpls_dev *mdev = container_of(head, struct mpls_dev, rcu); 1337 1338 free_percpu(mdev->stats); 1339 kfree(mdev); 1340 } 1341 1342 static void mpls_ifdown(struct net_device *dev, int event) 1343 { 1344 struct mpls_route __rcu **platform_label; 1345 struct net *net = dev_net(dev); 1346 u8 alive, deleted; 1347 unsigned index; 1348 1349 platform_label = rtnl_dereference(net->mpls.platform_label); 1350 for (index = 0; index < net->mpls.platform_labels; index++) { 1351 struct mpls_route *rt = rtnl_dereference(platform_label[index]); 1352 1353 if (!rt) 1354 continue; 1355 1356 alive = 0; 1357 deleted = 0; 1358 change_nexthops(rt) { 1359 unsigned int nh_flags = nh->nh_flags; 1360 1361 if (rtnl_dereference(nh->nh_dev) != dev) 1362 goto next; 1363 1364 switch (event) { 1365 case NETDEV_DOWN: 1366 case NETDEV_UNREGISTER: 1367 nh_flags |= RTNH_F_DEAD; 1368 /* fall through */ 1369 case NETDEV_CHANGE: 1370 nh_flags |= RTNH_F_LINKDOWN; 1371 break; 1372 } 1373 if (event == NETDEV_UNREGISTER) 1374 RCU_INIT_POINTER(nh->nh_dev, NULL); 1375 1376 if (nh->nh_flags != nh_flags) 1377 WRITE_ONCE(nh->nh_flags, nh_flags); 1378 next: 1379 if (!(nh_flags & (RTNH_F_DEAD | RTNH_F_LINKDOWN))) 1380 alive++; 1381 if (!rtnl_dereference(nh->nh_dev)) 1382 deleted++; 1383 } endfor_nexthops(rt); 1384 1385 WRITE_ONCE(rt->rt_nhn_alive, alive); 1386 1387 /* if there are no more nexthops, delete the route */ 1388 if (event == NETDEV_UNREGISTER && deleted == rt->rt_nhn) 1389 mpls_route_update(net, index, NULL, NULL); 1390 } 1391 } 1392 1393 static void mpls_ifup(struct net_device *dev, unsigned int flags) 1394 { 1395 struct mpls_route __rcu **platform_label; 1396 struct net *net = dev_net(dev); 1397 unsigned index; 1398 u8 alive; 1399 1400 platform_label = rtnl_dereference(net->mpls.platform_label); 1401 for (index = 0; index < net->mpls.platform_labels; index++) { 1402 struct mpls_route *rt = rtnl_dereference(platform_label[index]); 1403 1404 if (!rt) 1405 continue; 1406 1407 alive = 0; 1408 change_nexthops(rt) { 1409 unsigned int nh_flags = nh->nh_flags; 1410 struct net_device *nh_dev = 1411 rtnl_dereference(nh->nh_dev); 1412 1413 if (!(nh_flags & flags)) { 1414 alive++; 1415 continue; 1416 } 1417 if (nh_dev != dev) 1418 continue; 1419 alive++; 1420 nh_flags &= ~flags; 1421 WRITE_ONCE(nh->nh_flags, flags); 1422 } endfor_nexthops(rt); 1423 1424 WRITE_ONCE(rt->rt_nhn_alive, alive); 1425 } 1426 } 1427 1428 static int mpls_dev_notify(struct notifier_block *this, unsigned long event, 1429 void *ptr) 1430 { 1431 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 1432 struct mpls_dev *mdev; 1433 unsigned int flags; 1434 1435 if (event == NETDEV_REGISTER) { 1436 /* For now just support Ethernet, IPGRE, SIT and IPIP devices */ 1437 if (dev->type == ARPHRD_ETHER || 1438 dev->type == ARPHRD_LOOPBACK || 1439 dev->type == ARPHRD_IPGRE || 1440 dev->type == ARPHRD_SIT || 1441 dev->type == ARPHRD_TUNNEL) { 1442 mdev = mpls_add_dev(dev); 1443 if (IS_ERR(mdev)) 1444 return notifier_from_errno(PTR_ERR(mdev)); 1445 } 1446 return NOTIFY_OK; 1447 } 1448 1449 mdev = mpls_dev_get(dev); 1450 if (!mdev) 1451 return NOTIFY_OK; 1452 1453 switch (event) { 1454 case NETDEV_DOWN: 1455 mpls_ifdown(dev, event); 1456 break; 1457 case NETDEV_UP: 1458 flags = dev_get_flags(dev); 1459 if (flags & (IFF_RUNNING | IFF_LOWER_UP)) 1460 mpls_ifup(dev, RTNH_F_DEAD | RTNH_F_LINKDOWN); 1461 else 1462 mpls_ifup(dev, RTNH_F_DEAD); 1463 break; 1464 case NETDEV_CHANGE: 1465 flags = dev_get_flags(dev); 1466 if (flags & (IFF_RUNNING | IFF_LOWER_UP)) 1467 mpls_ifup(dev, RTNH_F_DEAD | RTNH_F_LINKDOWN); 1468 else 1469 mpls_ifdown(dev, event); 1470 break; 1471 case NETDEV_UNREGISTER: 1472 mpls_ifdown(dev, event); 1473 mdev = mpls_dev_get(dev); 1474 if (mdev) { 1475 mpls_dev_sysctl_unregister(dev, mdev); 1476 RCU_INIT_POINTER(dev->mpls_ptr, NULL); 1477 call_rcu(&mdev->rcu, mpls_dev_destroy_rcu); 1478 } 1479 break; 1480 case NETDEV_CHANGENAME: 1481 mdev = mpls_dev_get(dev); 1482 if (mdev) { 1483 int err; 1484 1485 mpls_dev_sysctl_unregister(dev, mdev); 1486 err = mpls_dev_sysctl_register(dev, mdev); 1487 if (err) 1488 return notifier_from_errno(err); 1489 } 1490 break; 1491 } 1492 return NOTIFY_OK; 1493 } 1494 1495 static struct notifier_block mpls_dev_notifier = { 1496 .notifier_call = mpls_dev_notify, 1497 }; 1498 1499 static int nla_put_via(struct sk_buff *skb, 1500 u8 table, const void *addr, int alen) 1501 { 1502 static const int table_to_family[NEIGH_NR_TABLES + 1] = { 1503 AF_INET, AF_INET6, AF_DECnet, AF_PACKET, 1504 }; 1505 struct nlattr *nla; 1506 struct rtvia *via; 1507 int family = AF_UNSPEC; 1508 1509 nla = nla_reserve(skb, RTA_VIA, alen + 2); 1510 if (!nla) 1511 return -EMSGSIZE; 1512 1513 if (table <= NEIGH_NR_TABLES) 1514 family = table_to_family[table]; 1515 1516 via = nla_data(nla); 1517 via->rtvia_family = family; 1518 memcpy(via->rtvia_addr, addr, alen); 1519 return 0; 1520 } 1521 1522 int nla_put_labels(struct sk_buff *skb, int attrtype, 1523 u8 labels, const u32 label[]) 1524 { 1525 struct nlattr *nla; 1526 struct mpls_shim_hdr *nla_label; 1527 bool bos; 1528 int i; 1529 nla = nla_reserve(skb, attrtype, labels*4); 1530 if (!nla) 1531 return -EMSGSIZE; 1532 1533 nla_label = nla_data(nla); 1534 bos = true; 1535 for (i = labels - 1; i >= 0; i--) { 1536 nla_label[i] = mpls_entry_encode(label[i], 0, 0, bos); 1537 bos = false; 1538 } 1539 1540 return 0; 1541 } 1542 EXPORT_SYMBOL_GPL(nla_put_labels); 1543 1544 int nla_get_labels(const struct nlattr *nla, 1545 u8 max_labels, u8 *labels, u32 label[]) 1546 { 1547 unsigned len = nla_len(nla); 1548 struct mpls_shim_hdr *nla_label; 1549 u8 nla_labels; 1550 bool bos; 1551 int i; 1552 1553 /* len needs to be an even multiple of 4 (the label size). Number 1554 * of labels is a u8 so check for overflow. 1555 */ 1556 if (len & 3 || len / 4 > 255) 1557 return -EINVAL; 1558 1559 /* Limit the number of new labels allowed */ 1560 nla_labels = len/4; 1561 if (nla_labels > max_labels) 1562 return -EINVAL; 1563 1564 /* when label == NULL, caller wants number of labels */ 1565 if (!label) 1566 goto out; 1567 1568 nla_label = nla_data(nla); 1569 bos = true; 1570 for (i = nla_labels - 1; i >= 0; i--, bos = false) { 1571 struct mpls_entry_decoded dec; 1572 dec = mpls_entry_decode(nla_label + i); 1573 1574 /* Ensure the bottom of stack flag is properly set 1575 * and ttl and tc are both clear. 1576 */ 1577 if ((dec.bos != bos) || dec.ttl || dec.tc) 1578 return -EINVAL; 1579 1580 switch (dec.label) { 1581 case MPLS_LABEL_IMPLNULL: 1582 /* RFC3032: This is a label that an LSR may 1583 * assign and distribute, but which never 1584 * actually appears in the encapsulation. 1585 */ 1586 return -EINVAL; 1587 } 1588 1589 label[i] = dec.label; 1590 } 1591 out: 1592 *labels = nla_labels; 1593 return 0; 1594 } 1595 EXPORT_SYMBOL_GPL(nla_get_labels); 1596 1597 int nla_get_via(const struct nlattr *nla, u8 *via_alen, 1598 u8 *via_table, u8 via_addr[]) 1599 { 1600 struct rtvia *via = nla_data(nla); 1601 int err = -EINVAL; 1602 int alen; 1603 1604 if (nla_len(nla) < offsetof(struct rtvia, rtvia_addr)) 1605 goto errout; 1606 alen = nla_len(nla) - 1607 offsetof(struct rtvia, rtvia_addr); 1608 if (alen > MAX_VIA_ALEN) 1609 goto errout; 1610 1611 /* Validate the address family */ 1612 switch (via->rtvia_family) { 1613 case AF_PACKET: 1614 *via_table = NEIGH_LINK_TABLE; 1615 break; 1616 case AF_INET: 1617 *via_table = NEIGH_ARP_TABLE; 1618 if (alen != 4) 1619 goto errout; 1620 break; 1621 case AF_INET6: 1622 *via_table = NEIGH_ND_TABLE; 1623 if (alen != 16) 1624 goto errout; 1625 break; 1626 default: 1627 /* Unsupported address family */ 1628 goto errout; 1629 } 1630 1631 memcpy(via_addr, via->rtvia_addr, alen); 1632 *via_alen = alen; 1633 err = 0; 1634 1635 errout: 1636 return err; 1637 } 1638 1639 static int rtm_to_route_config(struct sk_buff *skb, struct nlmsghdr *nlh, 1640 struct mpls_route_config *cfg) 1641 { 1642 struct rtmsg *rtm; 1643 struct nlattr *tb[RTA_MAX+1]; 1644 int index; 1645 int err; 1646 1647 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_mpls_policy, 1648 NULL); 1649 if (err < 0) 1650 goto errout; 1651 1652 err = -EINVAL; 1653 rtm = nlmsg_data(nlh); 1654 1655 if (rtm->rtm_family != AF_MPLS) 1656 goto errout; 1657 if (rtm->rtm_dst_len != 20) 1658 goto errout; 1659 if (rtm->rtm_src_len != 0) 1660 goto errout; 1661 if (rtm->rtm_tos != 0) 1662 goto errout; 1663 if (rtm->rtm_table != RT_TABLE_MAIN) 1664 goto errout; 1665 /* Any value is acceptable for rtm_protocol */ 1666 1667 /* As mpls uses destination specific addresses 1668 * (or source specific address in the case of multicast) 1669 * all addresses have universal scope. 1670 */ 1671 if (rtm->rtm_scope != RT_SCOPE_UNIVERSE) 1672 goto errout; 1673 if (rtm->rtm_type != RTN_UNICAST) 1674 goto errout; 1675 if (rtm->rtm_flags != 0) 1676 goto errout; 1677 1678 cfg->rc_label = LABEL_NOT_SPECIFIED; 1679 cfg->rc_protocol = rtm->rtm_protocol; 1680 cfg->rc_via_table = MPLS_NEIGH_TABLE_UNSPEC; 1681 cfg->rc_ttl_propagate = MPLS_TTL_PROP_DEFAULT; 1682 cfg->rc_nlflags = nlh->nlmsg_flags; 1683 cfg->rc_nlinfo.portid = NETLINK_CB(skb).portid; 1684 cfg->rc_nlinfo.nlh = nlh; 1685 cfg->rc_nlinfo.nl_net = sock_net(skb->sk); 1686 1687 for (index = 0; index <= RTA_MAX; index++) { 1688 struct nlattr *nla = tb[index]; 1689 if (!nla) 1690 continue; 1691 1692 switch (index) { 1693 case RTA_OIF: 1694 cfg->rc_ifindex = nla_get_u32(nla); 1695 break; 1696 case RTA_NEWDST: 1697 if (nla_get_labels(nla, MAX_NEW_LABELS, 1698 &cfg->rc_output_labels, 1699 cfg->rc_output_label)) 1700 goto errout; 1701 break; 1702 case RTA_DST: 1703 { 1704 u8 label_count; 1705 if (nla_get_labels(nla, 1, &label_count, 1706 &cfg->rc_label)) 1707 goto errout; 1708 1709 /* Reserved labels may not be set */ 1710 if (cfg->rc_label < MPLS_LABEL_FIRST_UNRESERVED) 1711 goto errout; 1712 1713 break; 1714 } 1715 case RTA_VIA: 1716 { 1717 if (nla_get_via(nla, &cfg->rc_via_alen, 1718 &cfg->rc_via_table, cfg->rc_via)) 1719 goto errout; 1720 break; 1721 } 1722 case RTA_MULTIPATH: 1723 { 1724 cfg->rc_mp = nla_data(nla); 1725 cfg->rc_mp_len = nla_len(nla); 1726 break; 1727 } 1728 case RTA_TTL_PROPAGATE: 1729 { 1730 u8 ttl_propagate = nla_get_u8(nla); 1731 1732 if (ttl_propagate > 1) 1733 goto errout; 1734 cfg->rc_ttl_propagate = ttl_propagate ? 1735 MPLS_TTL_PROP_ENABLED : 1736 MPLS_TTL_PROP_DISABLED; 1737 break; 1738 } 1739 default: 1740 /* Unsupported attribute */ 1741 goto errout; 1742 } 1743 } 1744 1745 err = 0; 1746 errout: 1747 return err; 1748 } 1749 1750 static int mpls_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh, 1751 struct netlink_ext_ack *extack) 1752 { 1753 struct mpls_route_config *cfg; 1754 int err; 1755 1756 cfg = kzalloc(sizeof(*cfg), GFP_KERNEL); 1757 if (!cfg) 1758 return -ENOMEM; 1759 1760 err = rtm_to_route_config(skb, nlh, cfg); 1761 if (err < 0) 1762 goto out; 1763 1764 err = mpls_route_del(cfg); 1765 out: 1766 kfree(cfg); 1767 1768 return err; 1769 } 1770 1771 1772 static int mpls_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh, 1773 struct netlink_ext_ack *extack) 1774 { 1775 struct mpls_route_config *cfg; 1776 int err; 1777 1778 cfg = kzalloc(sizeof(*cfg), GFP_KERNEL); 1779 if (!cfg) 1780 return -ENOMEM; 1781 1782 err = rtm_to_route_config(skb, nlh, cfg); 1783 if (err < 0) 1784 goto out; 1785 1786 err = mpls_route_add(cfg); 1787 out: 1788 kfree(cfg); 1789 1790 return err; 1791 } 1792 1793 static int mpls_dump_route(struct sk_buff *skb, u32 portid, u32 seq, int event, 1794 u32 label, struct mpls_route *rt, int flags) 1795 { 1796 struct net_device *dev; 1797 struct nlmsghdr *nlh; 1798 struct rtmsg *rtm; 1799 1800 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*rtm), flags); 1801 if (nlh == NULL) 1802 return -EMSGSIZE; 1803 1804 rtm = nlmsg_data(nlh); 1805 rtm->rtm_family = AF_MPLS; 1806 rtm->rtm_dst_len = 20; 1807 rtm->rtm_src_len = 0; 1808 rtm->rtm_tos = 0; 1809 rtm->rtm_table = RT_TABLE_MAIN; 1810 rtm->rtm_protocol = rt->rt_protocol; 1811 rtm->rtm_scope = RT_SCOPE_UNIVERSE; 1812 rtm->rtm_type = RTN_UNICAST; 1813 rtm->rtm_flags = 0; 1814 1815 if (nla_put_labels(skb, RTA_DST, 1, &label)) 1816 goto nla_put_failure; 1817 1818 if (rt->rt_ttl_propagate != MPLS_TTL_PROP_DEFAULT) { 1819 bool ttl_propagate = 1820 rt->rt_ttl_propagate == MPLS_TTL_PROP_ENABLED; 1821 1822 if (nla_put_u8(skb, RTA_TTL_PROPAGATE, 1823 ttl_propagate)) 1824 goto nla_put_failure; 1825 } 1826 if (rt->rt_nhn == 1) { 1827 const struct mpls_nh *nh = rt->rt_nh; 1828 1829 if (nh->nh_labels && 1830 nla_put_labels(skb, RTA_NEWDST, nh->nh_labels, 1831 nh->nh_label)) 1832 goto nla_put_failure; 1833 if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC && 1834 nla_put_via(skb, nh->nh_via_table, mpls_nh_via(rt, nh), 1835 nh->nh_via_alen)) 1836 goto nla_put_failure; 1837 dev = rtnl_dereference(nh->nh_dev); 1838 if (dev && nla_put_u32(skb, RTA_OIF, dev->ifindex)) 1839 goto nla_put_failure; 1840 if (nh->nh_flags & RTNH_F_LINKDOWN) 1841 rtm->rtm_flags |= RTNH_F_LINKDOWN; 1842 if (nh->nh_flags & RTNH_F_DEAD) 1843 rtm->rtm_flags |= RTNH_F_DEAD; 1844 } else { 1845 struct rtnexthop *rtnh; 1846 struct nlattr *mp; 1847 u8 linkdown = 0; 1848 u8 dead = 0; 1849 1850 mp = nla_nest_start(skb, RTA_MULTIPATH); 1851 if (!mp) 1852 goto nla_put_failure; 1853 1854 for_nexthops(rt) { 1855 dev = rtnl_dereference(nh->nh_dev); 1856 if (!dev) 1857 continue; 1858 1859 rtnh = nla_reserve_nohdr(skb, sizeof(*rtnh)); 1860 if (!rtnh) 1861 goto nla_put_failure; 1862 1863 rtnh->rtnh_ifindex = dev->ifindex; 1864 if (nh->nh_flags & RTNH_F_LINKDOWN) { 1865 rtnh->rtnh_flags |= RTNH_F_LINKDOWN; 1866 linkdown++; 1867 } 1868 if (nh->nh_flags & RTNH_F_DEAD) { 1869 rtnh->rtnh_flags |= RTNH_F_DEAD; 1870 dead++; 1871 } 1872 1873 if (nh->nh_labels && nla_put_labels(skb, RTA_NEWDST, 1874 nh->nh_labels, 1875 nh->nh_label)) 1876 goto nla_put_failure; 1877 if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC && 1878 nla_put_via(skb, nh->nh_via_table, 1879 mpls_nh_via(rt, nh), 1880 nh->nh_via_alen)) 1881 goto nla_put_failure; 1882 1883 /* length of rtnetlink header + attributes */ 1884 rtnh->rtnh_len = nlmsg_get_pos(skb) - (void *)rtnh; 1885 } endfor_nexthops(rt); 1886 1887 if (linkdown == rt->rt_nhn) 1888 rtm->rtm_flags |= RTNH_F_LINKDOWN; 1889 if (dead == rt->rt_nhn) 1890 rtm->rtm_flags |= RTNH_F_DEAD; 1891 1892 nla_nest_end(skb, mp); 1893 } 1894 1895 nlmsg_end(skb, nlh); 1896 return 0; 1897 1898 nla_put_failure: 1899 nlmsg_cancel(skb, nlh); 1900 return -EMSGSIZE; 1901 } 1902 1903 static int mpls_dump_routes(struct sk_buff *skb, struct netlink_callback *cb) 1904 { 1905 struct net *net = sock_net(skb->sk); 1906 struct mpls_route __rcu **platform_label; 1907 size_t platform_labels; 1908 unsigned int index; 1909 1910 ASSERT_RTNL(); 1911 1912 index = cb->args[0]; 1913 if (index < MPLS_LABEL_FIRST_UNRESERVED) 1914 index = MPLS_LABEL_FIRST_UNRESERVED; 1915 1916 platform_label = rtnl_dereference(net->mpls.platform_label); 1917 platform_labels = net->mpls.platform_labels; 1918 for (; index < platform_labels; index++) { 1919 struct mpls_route *rt; 1920 rt = rtnl_dereference(platform_label[index]); 1921 if (!rt) 1922 continue; 1923 1924 if (mpls_dump_route(skb, NETLINK_CB(cb->skb).portid, 1925 cb->nlh->nlmsg_seq, RTM_NEWROUTE, 1926 index, rt, NLM_F_MULTI) < 0) 1927 break; 1928 } 1929 cb->args[0] = index; 1930 1931 return skb->len; 1932 } 1933 1934 static inline size_t lfib_nlmsg_size(struct mpls_route *rt) 1935 { 1936 size_t payload = 1937 NLMSG_ALIGN(sizeof(struct rtmsg)) 1938 + nla_total_size(4) /* RTA_DST */ 1939 + nla_total_size(1); /* RTA_TTL_PROPAGATE */ 1940 1941 if (rt->rt_nhn == 1) { 1942 struct mpls_nh *nh = rt->rt_nh; 1943 1944 if (nh->nh_dev) 1945 payload += nla_total_size(4); /* RTA_OIF */ 1946 if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC) /* RTA_VIA */ 1947 payload += nla_total_size(2 + nh->nh_via_alen); 1948 if (nh->nh_labels) /* RTA_NEWDST */ 1949 payload += nla_total_size(nh->nh_labels * 4); 1950 } else { 1951 /* each nexthop is packed in an attribute */ 1952 size_t nhsize = 0; 1953 1954 for_nexthops(rt) { 1955 if (!rtnl_dereference(nh->nh_dev)) 1956 continue; 1957 nhsize += nla_total_size(sizeof(struct rtnexthop)); 1958 /* RTA_VIA */ 1959 if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC) 1960 nhsize += nla_total_size(2 + nh->nh_via_alen); 1961 if (nh->nh_labels) 1962 nhsize += nla_total_size(nh->nh_labels * 4); 1963 } endfor_nexthops(rt); 1964 /* nested attribute */ 1965 payload += nla_total_size(nhsize); 1966 } 1967 1968 return payload; 1969 } 1970 1971 static void rtmsg_lfib(int event, u32 label, struct mpls_route *rt, 1972 struct nlmsghdr *nlh, struct net *net, u32 portid, 1973 unsigned int nlm_flags) 1974 { 1975 struct sk_buff *skb; 1976 u32 seq = nlh ? nlh->nlmsg_seq : 0; 1977 int err = -ENOBUFS; 1978 1979 skb = nlmsg_new(lfib_nlmsg_size(rt), GFP_KERNEL); 1980 if (skb == NULL) 1981 goto errout; 1982 1983 err = mpls_dump_route(skb, portid, seq, event, label, rt, nlm_flags); 1984 if (err < 0) { 1985 /* -EMSGSIZE implies BUG in lfib_nlmsg_size */ 1986 WARN_ON(err == -EMSGSIZE); 1987 kfree_skb(skb); 1988 goto errout; 1989 } 1990 rtnl_notify(skb, net, portid, RTNLGRP_MPLS_ROUTE, nlh, GFP_KERNEL); 1991 1992 return; 1993 errout: 1994 if (err < 0) 1995 rtnl_set_sk_err(net, RTNLGRP_MPLS_ROUTE, err); 1996 } 1997 1998 static int resize_platform_label_table(struct net *net, size_t limit) 1999 { 2000 size_t size = sizeof(struct mpls_route *) * limit; 2001 size_t old_limit; 2002 size_t cp_size; 2003 struct mpls_route __rcu **labels = NULL, **old; 2004 struct mpls_route *rt0 = NULL, *rt2 = NULL; 2005 unsigned index; 2006 2007 if (size) { 2008 labels = kvzalloc(size, GFP_KERNEL); 2009 if (!labels) 2010 goto nolabels; 2011 } 2012 2013 /* In case the predefined labels need to be populated */ 2014 if (limit > MPLS_LABEL_IPV4NULL) { 2015 struct net_device *lo = net->loopback_dev; 2016 rt0 = mpls_rt_alloc(1, lo->addr_len, 0); 2017 if (IS_ERR(rt0)) 2018 goto nort0; 2019 RCU_INIT_POINTER(rt0->rt_nh->nh_dev, lo); 2020 rt0->rt_protocol = RTPROT_KERNEL; 2021 rt0->rt_payload_type = MPT_IPV4; 2022 rt0->rt_ttl_propagate = MPLS_TTL_PROP_DEFAULT; 2023 rt0->rt_nh->nh_via_table = NEIGH_LINK_TABLE; 2024 rt0->rt_nh->nh_via_alen = lo->addr_len; 2025 memcpy(__mpls_nh_via(rt0, rt0->rt_nh), lo->dev_addr, 2026 lo->addr_len); 2027 } 2028 if (limit > MPLS_LABEL_IPV6NULL) { 2029 struct net_device *lo = net->loopback_dev; 2030 rt2 = mpls_rt_alloc(1, lo->addr_len, 0); 2031 if (IS_ERR(rt2)) 2032 goto nort2; 2033 RCU_INIT_POINTER(rt2->rt_nh->nh_dev, lo); 2034 rt2->rt_protocol = RTPROT_KERNEL; 2035 rt2->rt_payload_type = MPT_IPV6; 2036 rt2->rt_ttl_propagate = MPLS_TTL_PROP_DEFAULT; 2037 rt2->rt_nh->nh_via_table = NEIGH_LINK_TABLE; 2038 rt2->rt_nh->nh_via_alen = lo->addr_len; 2039 memcpy(__mpls_nh_via(rt2, rt2->rt_nh), lo->dev_addr, 2040 lo->addr_len); 2041 } 2042 2043 rtnl_lock(); 2044 /* Remember the original table */ 2045 old = rtnl_dereference(net->mpls.platform_label); 2046 old_limit = net->mpls.platform_labels; 2047 2048 /* Free any labels beyond the new table */ 2049 for (index = limit; index < old_limit; index++) 2050 mpls_route_update(net, index, NULL, NULL); 2051 2052 /* Copy over the old labels */ 2053 cp_size = size; 2054 if (old_limit < limit) 2055 cp_size = old_limit * sizeof(struct mpls_route *); 2056 2057 memcpy(labels, old, cp_size); 2058 2059 /* If needed set the predefined labels */ 2060 if ((old_limit <= MPLS_LABEL_IPV6NULL) && 2061 (limit > MPLS_LABEL_IPV6NULL)) { 2062 RCU_INIT_POINTER(labels[MPLS_LABEL_IPV6NULL], rt2); 2063 rt2 = NULL; 2064 } 2065 2066 if ((old_limit <= MPLS_LABEL_IPV4NULL) && 2067 (limit > MPLS_LABEL_IPV4NULL)) { 2068 RCU_INIT_POINTER(labels[MPLS_LABEL_IPV4NULL], rt0); 2069 rt0 = NULL; 2070 } 2071 2072 /* Update the global pointers */ 2073 net->mpls.platform_labels = limit; 2074 rcu_assign_pointer(net->mpls.platform_label, labels); 2075 2076 rtnl_unlock(); 2077 2078 mpls_rt_free(rt2); 2079 mpls_rt_free(rt0); 2080 2081 if (old) { 2082 synchronize_rcu(); 2083 kvfree(old); 2084 } 2085 return 0; 2086 2087 nort2: 2088 mpls_rt_free(rt0); 2089 nort0: 2090 kvfree(labels); 2091 nolabels: 2092 return -ENOMEM; 2093 } 2094 2095 static int mpls_platform_labels(struct ctl_table *table, int write, 2096 void __user *buffer, size_t *lenp, loff_t *ppos) 2097 { 2098 struct net *net = table->data; 2099 int platform_labels = net->mpls.platform_labels; 2100 int ret; 2101 struct ctl_table tmp = { 2102 .procname = table->procname, 2103 .data = &platform_labels, 2104 .maxlen = sizeof(int), 2105 .mode = table->mode, 2106 .extra1 = &zero, 2107 .extra2 = &label_limit, 2108 }; 2109 2110 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos); 2111 2112 if (write && ret == 0) 2113 ret = resize_platform_label_table(net, platform_labels); 2114 2115 return ret; 2116 } 2117 2118 #define MPLS_NS_SYSCTL_OFFSET(field) \ 2119 (&((struct net *)0)->field) 2120 2121 static const struct ctl_table mpls_table[] = { 2122 { 2123 .procname = "platform_labels", 2124 .data = NULL, 2125 .maxlen = sizeof(int), 2126 .mode = 0644, 2127 .proc_handler = mpls_platform_labels, 2128 }, 2129 { 2130 .procname = "ip_ttl_propagate", 2131 .data = MPLS_NS_SYSCTL_OFFSET(mpls.ip_ttl_propagate), 2132 .maxlen = sizeof(int), 2133 .mode = 0644, 2134 .proc_handler = proc_dointvec_minmax, 2135 .extra1 = &zero, 2136 .extra2 = &one, 2137 }, 2138 { 2139 .procname = "default_ttl", 2140 .data = MPLS_NS_SYSCTL_OFFSET(mpls.default_ttl), 2141 .maxlen = sizeof(int), 2142 .mode = 0644, 2143 .proc_handler = proc_dointvec_minmax, 2144 .extra1 = &one, 2145 .extra2 = &ttl_max, 2146 }, 2147 { } 2148 }; 2149 2150 static int mpls_net_init(struct net *net) 2151 { 2152 struct ctl_table *table; 2153 int i; 2154 2155 net->mpls.platform_labels = 0; 2156 net->mpls.platform_label = NULL; 2157 net->mpls.ip_ttl_propagate = 1; 2158 net->mpls.default_ttl = 255; 2159 2160 table = kmemdup(mpls_table, sizeof(mpls_table), GFP_KERNEL); 2161 if (table == NULL) 2162 return -ENOMEM; 2163 2164 /* Table data contains only offsets relative to the base of 2165 * the mdev at this point, so make them absolute. 2166 */ 2167 for (i = 0; i < ARRAY_SIZE(mpls_table) - 1; i++) 2168 table[i].data = (char *)net + (uintptr_t)table[i].data; 2169 2170 net->mpls.ctl = register_net_sysctl(net, "net/mpls", table); 2171 if (net->mpls.ctl == NULL) { 2172 kfree(table); 2173 return -ENOMEM; 2174 } 2175 2176 return 0; 2177 } 2178 2179 static void mpls_net_exit(struct net *net) 2180 { 2181 struct mpls_route __rcu **platform_label; 2182 size_t platform_labels; 2183 struct ctl_table *table; 2184 unsigned int index; 2185 2186 table = net->mpls.ctl->ctl_table_arg; 2187 unregister_net_sysctl_table(net->mpls.ctl); 2188 kfree(table); 2189 2190 /* An rcu grace period has passed since there was a device in 2191 * the network namespace (and thus the last in flight packet) 2192 * left this network namespace. This is because 2193 * unregister_netdevice_many and netdev_run_todo has completed 2194 * for each network device that was in this network namespace. 2195 * 2196 * As such no additional rcu synchronization is necessary when 2197 * freeing the platform_label table. 2198 */ 2199 rtnl_lock(); 2200 platform_label = rtnl_dereference(net->mpls.platform_label); 2201 platform_labels = net->mpls.platform_labels; 2202 for (index = 0; index < platform_labels; index++) { 2203 struct mpls_route *rt = rtnl_dereference(platform_label[index]); 2204 RCU_INIT_POINTER(platform_label[index], NULL); 2205 mpls_notify_route(net, index, rt, NULL, NULL); 2206 mpls_rt_free(rt); 2207 } 2208 rtnl_unlock(); 2209 2210 kvfree(platform_label); 2211 } 2212 2213 static struct pernet_operations mpls_net_ops = { 2214 .init = mpls_net_init, 2215 .exit = mpls_net_exit, 2216 }; 2217 2218 static struct rtnl_af_ops mpls_af_ops __read_mostly = { 2219 .family = AF_MPLS, 2220 .fill_stats_af = mpls_fill_stats_af, 2221 .get_stats_af_size = mpls_get_stats_af_size, 2222 }; 2223 2224 static int __init mpls_init(void) 2225 { 2226 int err; 2227 2228 BUILD_BUG_ON(sizeof(struct mpls_shim_hdr) != 4); 2229 2230 err = register_pernet_subsys(&mpls_net_ops); 2231 if (err) 2232 goto out; 2233 2234 err = register_netdevice_notifier(&mpls_dev_notifier); 2235 if (err) 2236 goto out_unregister_pernet; 2237 2238 dev_add_pack(&mpls_packet_type); 2239 2240 rtnl_af_register(&mpls_af_ops); 2241 2242 rtnl_register(PF_MPLS, RTM_NEWROUTE, mpls_rtm_newroute, NULL, NULL); 2243 rtnl_register(PF_MPLS, RTM_DELROUTE, mpls_rtm_delroute, NULL, NULL); 2244 rtnl_register(PF_MPLS, RTM_GETROUTE, NULL, mpls_dump_routes, NULL); 2245 rtnl_register(PF_MPLS, RTM_GETNETCONF, mpls_netconf_get_devconf, 2246 mpls_netconf_dump_devconf, NULL); 2247 err = 0; 2248 out: 2249 return err; 2250 2251 out_unregister_pernet: 2252 unregister_pernet_subsys(&mpls_net_ops); 2253 goto out; 2254 } 2255 module_init(mpls_init); 2256 2257 static void __exit mpls_exit(void) 2258 { 2259 rtnl_unregister_all(PF_MPLS); 2260 rtnl_af_unregister(&mpls_af_ops); 2261 dev_remove_pack(&mpls_packet_type); 2262 unregister_netdevice_notifier(&mpls_dev_notifier); 2263 unregister_pernet_subsys(&mpls_net_ops); 2264 } 2265 module_exit(mpls_exit); 2266 2267 MODULE_DESCRIPTION("MultiProtocol Label Switching"); 2268 MODULE_LICENSE("GPL v2"); 2269 MODULE_ALIAS_NETPROTO(PF_MPLS); 2270