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/nospec.h> 12 #include <linux/vmalloc.h> 13 #include <linux/percpu.h> 14 #include <net/ip.h> 15 #include <net/dst.h> 16 #include <net/sock.h> 17 #include <net/arp.h> 18 #include <net/ip_fib.h> 19 #include <net/netevent.h> 20 #include <net/ip_tunnels.h> 21 #include <net/netns/generic.h> 22 #if IS_ENABLED(CONFIG_IPV6) 23 #include <net/ipv6.h> 24 #endif 25 #include <net/addrconf.h> 26 #include <net/nexthop.h> 27 #include "internal.h" 28 29 /* max memory we will use for mpls_route */ 30 #define MAX_MPLS_ROUTE_MEM 4096 31 32 /* Maximum number of labels to look ahead at when selecting a path of 33 * a multipath route 34 */ 35 #define MAX_MP_SELECT_LABELS 4 36 37 #define MPLS_NEIGH_TABLE_UNSPEC (NEIGH_LINK_TABLE + 1) 38 39 static int zero = 0; 40 static int one = 1; 41 static int label_limit = (1 << 20) - 1; 42 static int ttl_max = 255; 43 44 #if IS_ENABLED(CONFIG_NET_IP_TUNNEL) 45 static size_t ipgre_mpls_encap_hlen(struct ip_tunnel_encap *e) 46 { 47 return sizeof(struct mpls_shim_hdr); 48 } 49 50 static const struct ip_tunnel_encap_ops mpls_iptun_ops = { 51 .encap_hlen = ipgre_mpls_encap_hlen, 52 }; 53 54 static int ipgre_tunnel_encap_add_mpls_ops(void) 55 { 56 return ip_tunnel_encap_add_ops(&mpls_iptun_ops, TUNNEL_ENCAP_MPLS); 57 } 58 59 static void ipgre_tunnel_encap_del_mpls_ops(void) 60 { 61 ip_tunnel_encap_del_ops(&mpls_iptun_ops, TUNNEL_ENCAP_MPLS); 62 } 63 #else 64 static int ipgre_tunnel_encap_add_mpls_ops(void) 65 { 66 return 0; 67 } 68 69 static void ipgre_tunnel_encap_del_mpls_ops(void) 70 { 71 } 72 #endif 73 74 static void rtmsg_lfib(int event, u32 label, struct mpls_route *rt, 75 struct nlmsghdr *nlh, struct net *net, u32 portid, 76 unsigned int nlm_flags); 77 78 static struct mpls_route *mpls_route_input_rcu(struct net *net, unsigned index) 79 { 80 struct mpls_route *rt = NULL; 81 82 if (index < net->mpls.platform_labels) { 83 struct mpls_route __rcu **platform_label = 84 rcu_dereference(net->mpls.platform_label); 85 rt = rcu_dereference(platform_label[index]); 86 } 87 return rt; 88 } 89 90 bool mpls_output_possible(const struct net_device *dev) 91 { 92 return dev && (dev->flags & IFF_UP) && netif_carrier_ok(dev); 93 } 94 EXPORT_SYMBOL_GPL(mpls_output_possible); 95 96 static u8 *__mpls_nh_via(struct mpls_route *rt, struct mpls_nh *nh) 97 { 98 return (u8 *)nh + rt->rt_via_offset; 99 } 100 101 static const u8 *mpls_nh_via(const struct mpls_route *rt, 102 const struct mpls_nh *nh) 103 { 104 return __mpls_nh_via((struct mpls_route *)rt, (struct mpls_nh *)nh); 105 } 106 107 static unsigned int mpls_nh_header_size(const struct mpls_nh *nh) 108 { 109 /* The size of the layer 2.5 labels to be added for this route */ 110 return nh->nh_labels * sizeof(struct mpls_shim_hdr); 111 } 112 113 unsigned int mpls_dev_mtu(const struct net_device *dev) 114 { 115 /* The amount of data the layer 2 frame can hold */ 116 return dev->mtu; 117 } 118 EXPORT_SYMBOL_GPL(mpls_dev_mtu); 119 120 bool mpls_pkt_too_big(const struct sk_buff *skb, unsigned int mtu) 121 { 122 if (skb->len <= mtu) 123 return false; 124 125 if (skb_is_gso(skb) && skb_gso_validate_network_len(skb, mtu)) 126 return false; 127 128 return true; 129 } 130 EXPORT_SYMBOL_GPL(mpls_pkt_too_big); 131 132 void mpls_stats_inc_outucastpkts(struct net_device *dev, 133 const struct sk_buff *skb) 134 { 135 struct mpls_dev *mdev; 136 137 if (skb->protocol == htons(ETH_P_MPLS_UC)) { 138 mdev = mpls_dev_get(dev); 139 if (mdev) 140 MPLS_INC_STATS_LEN(mdev, skb->len, 141 tx_packets, 142 tx_bytes); 143 } else if (skb->protocol == htons(ETH_P_IP)) { 144 IP_UPD_PO_STATS(dev_net(dev), IPSTATS_MIB_OUT, skb->len); 145 #if IS_ENABLED(CONFIG_IPV6) 146 } else if (skb->protocol == htons(ETH_P_IPV6)) { 147 struct inet6_dev *in6dev = __in6_dev_get(dev); 148 149 if (in6dev) 150 IP6_UPD_PO_STATS(dev_net(dev), in6dev, 151 IPSTATS_MIB_OUT, skb->len); 152 #endif 153 } 154 } 155 EXPORT_SYMBOL_GPL(mpls_stats_inc_outucastpkts); 156 157 static u32 mpls_multipath_hash(struct mpls_route *rt, struct sk_buff *skb) 158 { 159 struct mpls_entry_decoded dec; 160 unsigned int mpls_hdr_len = 0; 161 struct mpls_shim_hdr *hdr; 162 bool eli_seen = false; 163 int label_index; 164 u32 hash = 0; 165 166 for (label_index = 0; label_index < MAX_MP_SELECT_LABELS; 167 label_index++) { 168 mpls_hdr_len += sizeof(*hdr); 169 if (!pskb_may_pull(skb, mpls_hdr_len)) 170 break; 171 172 /* Read and decode the current label */ 173 hdr = mpls_hdr(skb) + label_index; 174 dec = mpls_entry_decode(hdr); 175 176 /* RFC6790 - reserved labels MUST NOT be used as keys 177 * for the load-balancing function 178 */ 179 if (likely(dec.label >= MPLS_LABEL_FIRST_UNRESERVED)) { 180 hash = jhash_1word(dec.label, hash); 181 182 /* The entropy label follows the entropy label 183 * indicator, so this means that the entropy 184 * label was just added to the hash - no need to 185 * go any deeper either in the label stack or in the 186 * payload 187 */ 188 if (eli_seen) 189 break; 190 } else if (dec.label == MPLS_LABEL_ENTROPY) { 191 eli_seen = true; 192 } 193 194 if (!dec.bos) 195 continue; 196 197 /* found bottom label; does skb have room for a header? */ 198 if (pskb_may_pull(skb, mpls_hdr_len + sizeof(struct iphdr))) { 199 const struct iphdr *v4hdr; 200 201 v4hdr = (const struct iphdr *)(hdr + 1); 202 if (v4hdr->version == 4) { 203 hash = jhash_3words(ntohl(v4hdr->saddr), 204 ntohl(v4hdr->daddr), 205 v4hdr->protocol, hash); 206 } else if (v4hdr->version == 6 && 207 pskb_may_pull(skb, mpls_hdr_len + 208 sizeof(struct ipv6hdr))) { 209 const struct ipv6hdr *v6hdr; 210 211 v6hdr = (const struct ipv6hdr *)(hdr + 1); 212 hash = __ipv6_addr_jhash(&v6hdr->saddr, hash); 213 hash = __ipv6_addr_jhash(&v6hdr->daddr, hash); 214 hash = jhash_1word(v6hdr->nexthdr, hash); 215 } 216 } 217 218 break; 219 } 220 221 return hash; 222 } 223 224 static struct mpls_nh *mpls_get_nexthop(struct mpls_route *rt, u8 index) 225 { 226 return (struct mpls_nh *)((u8 *)rt->rt_nh + index * rt->rt_nh_size); 227 } 228 229 /* number of alive nexthops (rt->rt_nhn_alive) and the flags for 230 * a next hop (nh->nh_flags) are modified by netdev event handlers. 231 * Since those fields can change at any moment, use READ_ONCE to 232 * access both. 233 */ 234 static struct mpls_nh *mpls_select_multipath(struct mpls_route *rt, 235 struct sk_buff *skb) 236 { 237 u32 hash = 0; 238 int nh_index = 0; 239 int n = 0; 240 u8 alive; 241 242 /* No need to look further into packet if there's only 243 * one path 244 */ 245 if (rt->rt_nhn == 1) 246 return rt->rt_nh; 247 248 alive = READ_ONCE(rt->rt_nhn_alive); 249 if (alive == 0) 250 return NULL; 251 252 hash = mpls_multipath_hash(rt, skb); 253 nh_index = hash % alive; 254 if (alive == rt->rt_nhn) 255 goto out; 256 for_nexthops(rt) { 257 unsigned int nh_flags = READ_ONCE(nh->nh_flags); 258 259 if (nh_flags & (RTNH_F_DEAD | RTNH_F_LINKDOWN)) 260 continue; 261 if (n == nh_index) 262 return nh; 263 n++; 264 } endfor_nexthops(rt); 265 266 out: 267 return mpls_get_nexthop(rt, nh_index); 268 } 269 270 static bool mpls_egress(struct net *net, struct mpls_route *rt, 271 struct sk_buff *skb, struct mpls_entry_decoded dec) 272 { 273 enum mpls_payload_type payload_type; 274 bool success = false; 275 276 /* The IPv4 code below accesses through the IPv4 header 277 * checksum, which is 12 bytes into the packet. 278 * The IPv6 code below accesses through the IPv6 hop limit 279 * which is 8 bytes into the packet. 280 * 281 * For all supported cases there should always be at least 12 282 * bytes of packet data present. The IPv4 header is 20 bytes 283 * without options and the IPv6 header is always 40 bytes 284 * long. 285 */ 286 if (!pskb_may_pull(skb, 12)) 287 return false; 288 289 payload_type = rt->rt_payload_type; 290 if (payload_type == MPT_UNSPEC) 291 payload_type = ip_hdr(skb)->version; 292 293 switch (payload_type) { 294 case MPT_IPV4: { 295 struct iphdr *hdr4 = ip_hdr(skb); 296 u8 new_ttl; 297 skb->protocol = htons(ETH_P_IP); 298 299 /* If propagating TTL, take the decremented TTL from 300 * the incoming MPLS header, otherwise decrement the 301 * TTL, but only if not 0 to avoid underflow. 302 */ 303 if (rt->rt_ttl_propagate == MPLS_TTL_PROP_ENABLED || 304 (rt->rt_ttl_propagate == MPLS_TTL_PROP_DEFAULT && 305 net->mpls.ip_ttl_propagate)) 306 new_ttl = dec.ttl; 307 else 308 new_ttl = hdr4->ttl ? hdr4->ttl - 1 : 0; 309 310 csum_replace2(&hdr4->check, 311 htons(hdr4->ttl << 8), 312 htons(new_ttl << 8)); 313 hdr4->ttl = new_ttl; 314 success = true; 315 break; 316 } 317 case MPT_IPV6: { 318 struct ipv6hdr *hdr6 = ipv6_hdr(skb); 319 skb->protocol = htons(ETH_P_IPV6); 320 321 /* If propagating TTL, take the decremented TTL from 322 * the incoming MPLS header, otherwise decrement the 323 * hop limit, but only if not 0 to avoid underflow. 324 */ 325 if (rt->rt_ttl_propagate == MPLS_TTL_PROP_ENABLED || 326 (rt->rt_ttl_propagate == MPLS_TTL_PROP_DEFAULT && 327 net->mpls.ip_ttl_propagate)) 328 hdr6->hop_limit = dec.ttl; 329 else if (hdr6->hop_limit) 330 hdr6->hop_limit = hdr6->hop_limit - 1; 331 success = true; 332 break; 333 } 334 case MPT_UNSPEC: 335 /* Should have decided which protocol it is by now */ 336 break; 337 } 338 339 return success; 340 } 341 342 static int mpls_forward(struct sk_buff *skb, struct net_device *dev, 343 struct packet_type *pt, struct net_device *orig_dev) 344 { 345 struct net *net = dev_net(dev); 346 struct mpls_shim_hdr *hdr; 347 struct mpls_route *rt; 348 struct mpls_nh *nh; 349 struct mpls_entry_decoded dec; 350 struct net_device *out_dev; 351 struct mpls_dev *out_mdev; 352 struct mpls_dev *mdev; 353 unsigned int hh_len; 354 unsigned int new_header_size; 355 unsigned int mtu; 356 int err; 357 358 /* Careful this entire function runs inside of an rcu critical section */ 359 360 mdev = mpls_dev_get(dev); 361 if (!mdev) 362 goto drop; 363 364 MPLS_INC_STATS_LEN(mdev, skb->len, rx_packets, 365 rx_bytes); 366 367 if (!mdev->input_enabled) { 368 MPLS_INC_STATS(mdev, rx_dropped); 369 goto drop; 370 } 371 372 if (skb->pkt_type != PACKET_HOST) 373 goto err; 374 375 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL) 376 goto err; 377 378 if (!pskb_may_pull(skb, sizeof(*hdr))) 379 goto err; 380 381 /* Read and decode the label */ 382 hdr = mpls_hdr(skb); 383 dec = mpls_entry_decode(hdr); 384 385 rt = mpls_route_input_rcu(net, dec.label); 386 if (!rt) { 387 MPLS_INC_STATS(mdev, rx_noroute); 388 goto drop; 389 } 390 391 nh = mpls_select_multipath(rt, skb); 392 if (!nh) 393 goto err; 394 395 /* Pop the label */ 396 skb_pull(skb, sizeof(*hdr)); 397 skb_reset_network_header(skb); 398 399 skb_orphan(skb); 400 401 if (skb_warn_if_lro(skb)) 402 goto err; 403 404 skb_forward_csum(skb); 405 406 /* Verify ttl is valid */ 407 if (dec.ttl <= 1) 408 goto err; 409 dec.ttl -= 1; 410 411 /* Find the output device */ 412 out_dev = rcu_dereference(nh->nh_dev); 413 if (!mpls_output_possible(out_dev)) 414 goto tx_err; 415 416 /* Verify the destination can hold the packet */ 417 new_header_size = mpls_nh_header_size(nh); 418 mtu = mpls_dev_mtu(out_dev); 419 if (mpls_pkt_too_big(skb, mtu - new_header_size)) 420 goto tx_err; 421 422 hh_len = LL_RESERVED_SPACE(out_dev); 423 if (!out_dev->header_ops) 424 hh_len = 0; 425 426 /* Ensure there is enough space for the headers in the skb */ 427 if (skb_cow(skb, hh_len + new_header_size)) 428 goto tx_err; 429 430 skb->dev = out_dev; 431 skb->protocol = htons(ETH_P_MPLS_UC); 432 433 if (unlikely(!new_header_size && dec.bos)) { 434 /* Penultimate hop popping */ 435 if (!mpls_egress(dev_net(out_dev), rt, skb, dec)) 436 goto err; 437 } else { 438 bool bos; 439 int i; 440 skb_push(skb, new_header_size); 441 skb_reset_network_header(skb); 442 /* Push the new labels */ 443 hdr = mpls_hdr(skb); 444 bos = dec.bos; 445 for (i = nh->nh_labels - 1; i >= 0; i--) { 446 hdr[i] = mpls_entry_encode(nh->nh_label[i], 447 dec.ttl, 0, bos); 448 bos = false; 449 } 450 } 451 452 mpls_stats_inc_outucastpkts(out_dev, skb); 453 454 /* If via wasn't specified then send out using device address */ 455 if (nh->nh_via_table == MPLS_NEIGH_TABLE_UNSPEC) 456 err = neigh_xmit(NEIGH_LINK_TABLE, out_dev, 457 out_dev->dev_addr, skb); 458 else 459 err = neigh_xmit(nh->nh_via_table, out_dev, 460 mpls_nh_via(rt, nh), skb); 461 if (err) 462 net_dbg_ratelimited("%s: packet transmission failed: %d\n", 463 __func__, err); 464 return 0; 465 466 tx_err: 467 out_mdev = out_dev ? mpls_dev_get(out_dev) : NULL; 468 if (out_mdev) 469 MPLS_INC_STATS(out_mdev, tx_errors); 470 goto drop; 471 err: 472 MPLS_INC_STATS(mdev, rx_errors); 473 drop: 474 kfree_skb(skb); 475 return NET_RX_DROP; 476 } 477 478 static struct packet_type mpls_packet_type __read_mostly = { 479 .type = cpu_to_be16(ETH_P_MPLS_UC), 480 .func = mpls_forward, 481 }; 482 483 static const struct nla_policy rtm_mpls_policy[RTA_MAX+1] = { 484 [RTA_DST] = { .type = NLA_U32 }, 485 [RTA_OIF] = { .type = NLA_U32 }, 486 [RTA_TTL_PROPAGATE] = { .type = NLA_U8 }, 487 }; 488 489 struct mpls_route_config { 490 u32 rc_protocol; 491 u32 rc_ifindex; 492 u8 rc_via_table; 493 u8 rc_via_alen; 494 u8 rc_via[MAX_VIA_ALEN]; 495 u32 rc_label; 496 u8 rc_ttl_propagate; 497 u8 rc_output_labels; 498 u32 rc_output_label[MAX_NEW_LABELS]; 499 u32 rc_nlflags; 500 enum mpls_payload_type rc_payload_type; 501 struct nl_info rc_nlinfo; 502 struct rtnexthop *rc_mp; 503 int rc_mp_len; 504 }; 505 506 /* all nexthops within a route have the same size based on max 507 * number of labels and max via length for a hop 508 */ 509 static struct mpls_route *mpls_rt_alloc(u8 num_nh, u8 max_alen, u8 max_labels) 510 { 511 u8 nh_size = MPLS_NH_SIZE(max_labels, max_alen); 512 struct mpls_route *rt; 513 size_t size; 514 515 size = sizeof(*rt) + num_nh * nh_size; 516 if (size > MAX_MPLS_ROUTE_MEM) 517 return ERR_PTR(-EINVAL); 518 519 rt = kzalloc(size, GFP_KERNEL); 520 if (!rt) 521 return ERR_PTR(-ENOMEM); 522 523 rt->rt_nhn = num_nh; 524 rt->rt_nhn_alive = num_nh; 525 rt->rt_nh_size = nh_size; 526 rt->rt_via_offset = MPLS_NH_VIA_OFF(max_labels); 527 528 return rt; 529 } 530 531 static void mpls_rt_free(struct mpls_route *rt) 532 { 533 if (rt) 534 kfree_rcu(rt, rt_rcu); 535 } 536 537 static void mpls_notify_route(struct net *net, unsigned index, 538 struct mpls_route *old, struct mpls_route *new, 539 const struct nl_info *info) 540 { 541 struct nlmsghdr *nlh = info ? info->nlh : NULL; 542 unsigned portid = info ? info->portid : 0; 543 int event = new ? RTM_NEWROUTE : RTM_DELROUTE; 544 struct mpls_route *rt = new ? new : old; 545 unsigned nlm_flags = (old && new) ? NLM_F_REPLACE : 0; 546 /* Ignore reserved labels for now */ 547 if (rt && (index >= MPLS_LABEL_FIRST_UNRESERVED)) 548 rtmsg_lfib(event, index, rt, nlh, net, portid, nlm_flags); 549 } 550 551 static void mpls_route_update(struct net *net, unsigned index, 552 struct mpls_route *new, 553 const struct nl_info *info) 554 { 555 struct mpls_route __rcu **platform_label; 556 struct mpls_route *rt; 557 558 ASSERT_RTNL(); 559 560 platform_label = rtnl_dereference(net->mpls.platform_label); 561 rt = rtnl_dereference(platform_label[index]); 562 rcu_assign_pointer(platform_label[index], new); 563 564 mpls_notify_route(net, index, rt, new, info); 565 566 /* If we removed a route free it now */ 567 mpls_rt_free(rt); 568 } 569 570 static unsigned find_free_label(struct net *net) 571 { 572 struct mpls_route __rcu **platform_label; 573 size_t platform_labels; 574 unsigned index; 575 576 platform_label = rtnl_dereference(net->mpls.platform_label); 577 platform_labels = net->mpls.platform_labels; 578 for (index = MPLS_LABEL_FIRST_UNRESERVED; index < platform_labels; 579 index++) { 580 if (!rtnl_dereference(platform_label[index])) 581 return index; 582 } 583 return LABEL_NOT_SPECIFIED; 584 } 585 586 #if IS_ENABLED(CONFIG_INET) 587 static struct net_device *inet_fib_lookup_dev(struct net *net, 588 const void *addr) 589 { 590 struct net_device *dev; 591 struct rtable *rt; 592 struct in_addr daddr; 593 594 memcpy(&daddr, addr, sizeof(struct in_addr)); 595 rt = ip_route_output(net, daddr.s_addr, 0, 0, 0); 596 if (IS_ERR(rt)) 597 return ERR_CAST(rt); 598 599 dev = rt->dst.dev; 600 dev_hold(dev); 601 602 ip_rt_put(rt); 603 604 return dev; 605 } 606 #else 607 static struct net_device *inet_fib_lookup_dev(struct net *net, 608 const void *addr) 609 { 610 return ERR_PTR(-EAFNOSUPPORT); 611 } 612 #endif 613 614 #if IS_ENABLED(CONFIG_IPV6) 615 static struct net_device *inet6_fib_lookup_dev(struct net *net, 616 const void *addr) 617 { 618 struct net_device *dev; 619 struct dst_entry *dst; 620 struct flowi6 fl6; 621 int err; 622 623 if (!ipv6_stub) 624 return ERR_PTR(-EAFNOSUPPORT); 625 626 memset(&fl6, 0, sizeof(fl6)); 627 memcpy(&fl6.daddr, addr, sizeof(struct in6_addr)); 628 err = ipv6_stub->ipv6_dst_lookup(net, NULL, &dst, &fl6); 629 if (err) 630 return ERR_PTR(err); 631 632 dev = dst->dev; 633 dev_hold(dev); 634 dst_release(dst); 635 636 return dev; 637 } 638 #else 639 static struct net_device *inet6_fib_lookup_dev(struct net *net, 640 const void *addr) 641 { 642 return ERR_PTR(-EAFNOSUPPORT); 643 } 644 #endif 645 646 static struct net_device *find_outdev(struct net *net, 647 struct mpls_route *rt, 648 struct mpls_nh *nh, int oif) 649 { 650 struct net_device *dev = NULL; 651 652 if (!oif) { 653 switch (nh->nh_via_table) { 654 case NEIGH_ARP_TABLE: 655 dev = inet_fib_lookup_dev(net, mpls_nh_via(rt, nh)); 656 break; 657 case NEIGH_ND_TABLE: 658 dev = inet6_fib_lookup_dev(net, mpls_nh_via(rt, nh)); 659 break; 660 case NEIGH_LINK_TABLE: 661 break; 662 } 663 } else { 664 dev = dev_get_by_index(net, oif); 665 } 666 667 if (!dev) 668 return ERR_PTR(-ENODEV); 669 670 if (IS_ERR(dev)) 671 return dev; 672 673 /* The caller is holding rtnl anyways, so release the dev reference */ 674 dev_put(dev); 675 676 return dev; 677 } 678 679 static int mpls_nh_assign_dev(struct net *net, struct mpls_route *rt, 680 struct mpls_nh *nh, int oif) 681 { 682 struct net_device *dev = NULL; 683 int err = -ENODEV; 684 685 dev = find_outdev(net, rt, nh, oif); 686 if (IS_ERR(dev)) { 687 err = PTR_ERR(dev); 688 dev = NULL; 689 goto errout; 690 } 691 692 /* Ensure this is a supported device */ 693 err = -EINVAL; 694 if (!mpls_dev_get(dev)) 695 goto errout; 696 697 if ((nh->nh_via_table == NEIGH_LINK_TABLE) && 698 (dev->addr_len != nh->nh_via_alen)) 699 goto errout; 700 701 RCU_INIT_POINTER(nh->nh_dev, dev); 702 703 if (!(dev->flags & IFF_UP)) { 704 nh->nh_flags |= RTNH_F_DEAD; 705 } else { 706 unsigned int flags; 707 708 flags = dev_get_flags(dev); 709 if (!(flags & (IFF_RUNNING | IFF_LOWER_UP))) 710 nh->nh_flags |= RTNH_F_LINKDOWN; 711 } 712 713 return 0; 714 715 errout: 716 return err; 717 } 718 719 static int nla_get_via(const struct nlattr *nla, u8 *via_alen, u8 *via_table, 720 u8 via_addr[], struct netlink_ext_ack *extack) 721 { 722 struct rtvia *via = nla_data(nla); 723 int err = -EINVAL; 724 int alen; 725 726 if (nla_len(nla) < offsetof(struct rtvia, rtvia_addr)) { 727 NL_SET_ERR_MSG_ATTR(extack, nla, 728 "Invalid attribute length for RTA_VIA"); 729 goto errout; 730 } 731 alen = nla_len(nla) - 732 offsetof(struct rtvia, rtvia_addr); 733 if (alen > MAX_VIA_ALEN) { 734 NL_SET_ERR_MSG_ATTR(extack, nla, 735 "Invalid address length for RTA_VIA"); 736 goto errout; 737 } 738 739 /* Validate the address family */ 740 switch (via->rtvia_family) { 741 case AF_PACKET: 742 *via_table = NEIGH_LINK_TABLE; 743 break; 744 case AF_INET: 745 *via_table = NEIGH_ARP_TABLE; 746 if (alen != 4) 747 goto errout; 748 break; 749 case AF_INET6: 750 *via_table = NEIGH_ND_TABLE; 751 if (alen != 16) 752 goto errout; 753 break; 754 default: 755 /* Unsupported address family */ 756 goto errout; 757 } 758 759 memcpy(via_addr, via->rtvia_addr, alen); 760 *via_alen = alen; 761 err = 0; 762 763 errout: 764 return err; 765 } 766 767 static int mpls_nh_build_from_cfg(struct mpls_route_config *cfg, 768 struct mpls_route *rt) 769 { 770 struct net *net = cfg->rc_nlinfo.nl_net; 771 struct mpls_nh *nh = rt->rt_nh; 772 int err; 773 int i; 774 775 if (!nh) 776 return -ENOMEM; 777 778 nh->nh_labels = cfg->rc_output_labels; 779 for (i = 0; i < nh->nh_labels; i++) 780 nh->nh_label[i] = cfg->rc_output_label[i]; 781 782 nh->nh_via_table = cfg->rc_via_table; 783 memcpy(__mpls_nh_via(rt, nh), cfg->rc_via, cfg->rc_via_alen); 784 nh->nh_via_alen = cfg->rc_via_alen; 785 786 err = mpls_nh_assign_dev(net, rt, nh, cfg->rc_ifindex); 787 if (err) 788 goto errout; 789 790 if (nh->nh_flags & (RTNH_F_DEAD | RTNH_F_LINKDOWN)) 791 rt->rt_nhn_alive--; 792 793 return 0; 794 795 errout: 796 return err; 797 } 798 799 static int mpls_nh_build(struct net *net, struct mpls_route *rt, 800 struct mpls_nh *nh, int oif, struct nlattr *via, 801 struct nlattr *newdst, u8 max_labels, 802 struct netlink_ext_ack *extack) 803 { 804 int err = -ENOMEM; 805 806 if (!nh) 807 goto errout; 808 809 if (newdst) { 810 err = nla_get_labels(newdst, max_labels, &nh->nh_labels, 811 nh->nh_label, extack); 812 if (err) 813 goto errout; 814 } 815 816 if (via) { 817 err = nla_get_via(via, &nh->nh_via_alen, &nh->nh_via_table, 818 __mpls_nh_via(rt, nh), extack); 819 if (err) 820 goto errout; 821 } else { 822 nh->nh_via_table = MPLS_NEIGH_TABLE_UNSPEC; 823 } 824 825 err = mpls_nh_assign_dev(net, rt, nh, oif); 826 if (err) 827 goto errout; 828 829 return 0; 830 831 errout: 832 return err; 833 } 834 835 static u8 mpls_count_nexthops(struct rtnexthop *rtnh, int len, 836 u8 cfg_via_alen, u8 *max_via_alen, 837 u8 *max_labels) 838 { 839 int remaining = len; 840 u8 nhs = 0; 841 842 *max_via_alen = 0; 843 *max_labels = 0; 844 845 while (rtnh_ok(rtnh, remaining)) { 846 struct nlattr *nla, *attrs = rtnh_attrs(rtnh); 847 int attrlen; 848 u8 n_labels = 0; 849 850 attrlen = rtnh_attrlen(rtnh); 851 nla = nla_find(attrs, attrlen, RTA_VIA); 852 if (nla && nla_len(nla) >= 853 offsetof(struct rtvia, rtvia_addr)) { 854 int via_alen = nla_len(nla) - 855 offsetof(struct rtvia, rtvia_addr); 856 857 if (via_alen <= MAX_VIA_ALEN) 858 *max_via_alen = max_t(u16, *max_via_alen, 859 via_alen); 860 } 861 862 nla = nla_find(attrs, attrlen, RTA_NEWDST); 863 if (nla && 864 nla_get_labels(nla, MAX_NEW_LABELS, &n_labels, 865 NULL, NULL) != 0) 866 return 0; 867 868 *max_labels = max_t(u8, *max_labels, n_labels); 869 870 /* number of nexthops is tracked by a u8. 871 * Check for overflow. 872 */ 873 if (nhs == 255) 874 return 0; 875 nhs++; 876 877 rtnh = rtnh_next(rtnh, &remaining); 878 } 879 880 /* leftover implies invalid nexthop configuration, discard it */ 881 return remaining > 0 ? 0 : nhs; 882 } 883 884 static int mpls_nh_build_multi(struct mpls_route_config *cfg, 885 struct mpls_route *rt, u8 max_labels, 886 struct netlink_ext_ack *extack) 887 { 888 struct rtnexthop *rtnh = cfg->rc_mp; 889 struct nlattr *nla_via, *nla_newdst; 890 int remaining = cfg->rc_mp_len; 891 int err = 0; 892 u8 nhs = 0; 893 894 change_nexthops(rt) { 895 int attrlen; 896 897 nla_via = NULL; 898 nla_newdst = NULL; 899 900 err = -EINVAL; 901 if (!rtnh_ok(rtnh, remaining)) 902 goto errout; 903 904 /* neither weighted multipath nor any flags 905 * are supported 906 */ 907 if (rtnh->rtnh_hops || rtnh->rtnh_flags) 908 goto errout; 909 910 attrlen = rtnh_attrlen(rtnh); 911 if (attrlen > 0) { 912 struct nlattr *attrs = rtnh_attrs(rtnh); 913 914 nla_via = nla_find(attrs, attrlen, RTA_VIA); 915 nla_newdst = nla_find(attrs, attrlen, RTA_NEWDST); 916 } 917 918 err = mpls_nh_build(cfg->rc_nlinfo.nl_net, rt, nh, 919 rtnh->rtnh_ifindex, nla_via, nla_newdst, 920 max_labels, extack); 921 if (err) 922 goto errout; 923 924 if (nh->nh_flags & (RTNH_F_DEAD | RTNH_F_LINKDOWN)) 925 rt->rt_nhn_alive--; 926 927 rtnh = rtnh_next(rtnh, &remaining); 928 nhs++; 929 } endfor_nexthops(rt); 930 931 rt->rt_nhn = nhs; 932 933 return 0; 934 935 errout: 936 return err; 937 } 938 939 static bool mpls_label_ok(struct net *net, unsigned int *index, 940 struct netlink_ext_ack *extack) 941 { 942 bool is_ok = true; 943 944 /* Reserved labels may not be set */ 945 if (*index < MPLS_LABEL_FIRST_UNRESERVED) { 946 NL_SET_ERR_MSG(extack, 947 "Invalid label - must be MPLS_LABEL_FIRST_UNRESERVED or higher"); 948 is_ok = false; 949 } 950 951 /* The full 20 bit range may not be supported. */ 952 if (is_ok && *index >= net->mpls.platform_labels) { 953 NL_SET_ERR_MSG(extack, 954 "Label >= configured maximum in platform_labels"); 955 is_ok = false; 956 } 957 958 *index = array_index_nospec(*index, net->mpls.platform_labels); 959 return is_ok; 960 } 961 962 static int mpls_route_add(struct mpls_route_config *cfg, 963 struct netlink_ext_ack *extack) 964 { 965 struct mpls_route __rcu **platform_label; 966 struct net *net = cfg->rc_nlinfo.nl_net; 967 struct mpls_route *rt, *old; 968 int err = -EINVAL; 969 u8 max_via_alen; 970 unsigned index; 971 u8 max_labels; 972 u8 nhs; 973 974 index = cfg->rc_label; 975 976 /* If a label was not specified during insert pick one */ 977 if ((index == LABEL_NOT_SPECIFIED) && 978 (cfg->rc_nlflags & NLM_F_CREATE)) { 979 index = find_free_label(net); 980 } 981 982 if (!mpls_label_ok(net, &index, extack)) 983 goto errout; 984 985 /* Append makes no sense with mpls */ 986 err = -EOPNOTSUPP; 987 if (cfg->rc_nlflags & NLM_F_APPEND) { 988 NL_SET_ERR_MSG(extack, "MPLS does not support route append"); 989 goto errout; 990 } 991 992 err = -EEXIST; 993 platform_label = rtnl_dereference(net->mpls.platform_label); 994 old = rtnl_dereference(platform_label[index]); 995 if ((cfg->rc_nlflags & NLM_F_EXCL) && old) 996 goto errout; 997 998 err = -EEXIST; 999 if (!(cfg->rc_nlflags & NLM_F_REPLACE) && old) 1000 goto errout; 1001 1002 err = -ENOENT; 1003 if (!(cfg->rc_nlflags & NLM_F_CREATE) && !old) 1004 goto errout; 1005 1006 err = -EINVAL; 1007 if (cfg->rc_mp) { 1008 nhs = mpls_count_nexthops(cfg->rc_mp, cfg->rc_mp_len, 1009 cfg->rc_via_alen, &max_via_alen, 1010 &max_labels); 1011 } else { 1012 max_via_alen = cfg->rc_via_alen; 1013 max_labels = cfg->rc_output_labels; 1014 nhs = 1; 1015 } 1016 1017 if (nhs == 0) { 1018 NL_SET_ERR_MSG(extack, "Route does not contain a nexthop"); 1019 goto errout; 1020 } 1021 1022 err = -ENOMEM; 1023 rt = mpls_rt_alloc(nhs, max_via_alen, max_labels); 1024 if (IS_ERR(rt)) { 1025 err = PTR_ERR(rt); 1026 goto errout; 1027 } 1028 1029 rt->rt_protocol = cfg->rc_protocol; 1030 rt->rt_payload_type = cfg->rc_payload_type; 1031 rt->rt_ttl_propagate = cfg->rc_ttl_propagate; 1032 1033 if (cfg->rc_mp) 1034 err = mpls_nh_build_multi(cfg, rt, max_labels, extack); 1035 else 1036 err = mpls_nh_build_from_cfg(cfg, rt); 1037 if (err) 1038 goto freert; 1039 1040 mpls_route_update(net, index, rt, &cfg->rc_nlinfo); 1041 1042 return 0; 1043 1044 freert: 1045 mpls_rt_free(rt); 1046 errout: 1047 return err; 1048 } 1049 1050 static int mpls_route_del(struct mpls_route_config *cfg, 1051 struct netlink_ext_ack *extack) 1052 { 1053 struct net *net = cfg->rc_nlinfo.nl_net; 1054 unsigned index; 1055 int err = -EINVAL; 1056 1057 index = cfg->rc_label; 1058 1059 if (!mpls_label_ok(net, &index, extack)) 1060 goto errout; 1061 1062 mpls_route_update(net, index, NULL, &cfg->rc_nlinfo); 1063 1064 err = 0; 1065 errout: 1066 return err; 1067 } 1068 1069 static void mpls_get_stats(struct mpls_dev *mdev, 1070 struct mpls_link_stats *stats) 1071 { 1072 struct mpls_pcpu_stats *p; 1073 int i; 1074 1075 memset(stats, 0, sizeof(*stats)); 1076 1077 for_each_possible_cpu(i) { 1078 struct mpls_link_stats local; 1079 unsigned int start; 1080 1081 p = per_cpu_ptr(mdev->stats, i); 1082 do { 1083 start = u64_stats_fetch_begin(&p->syncp); 1084 local = p->stats; 1085 } while (u64_stats_fetch_retry(&p->syncp, start)); 1086 1087 stats->rx_packets += local.rx_packets; 1088 stats->rx_bytes += local.rx_bytes; 1089 stats->tx_packets += local.tx_packets; 1090 stats->tx_bytes += local.tx_bytes; 1091 stats->rx_errors += local.rx_errors; 1092 stats->tx_errors += local.tx_errors; 1093 stats->rx_dropped += local.rx_dropped; 1094 stats->tx_dropped += local.tx_dropped; 1095 stats->rx_noroute += local.rx_noroute; 1096 } 1097 } 1098 1099 static int mpls_fill_stats_af(struct sk_buff *skb, 1100 const struct net_device *dev) 1101 { 1102 struct mpls_link_stats *stats; 1103 struct mpls_dev *mdev; 1104 struct nlattr *nla; 1105 1106 mdev = mpls_dev_get(dev); 1107 if (!mdev) 1108 return -ENODATA; 1109 1110 nla = nla_reserve_64bit(skb, MPLS_STATS_LINK, 1111 sizeof(struct mpls_link_stats), 1112 MPLS_STATS_UNSPEC); 1113 if (!nla) 1114 return -EMSGSIZE; 1115 1116 stats = nla_data(nla); 1117 mpls_get_stats(mdev, stats); 1118 1119 return 0; 1120 } 1121 1122 static size_t mpls_get_stats_af_size(const struct net_device *dev) 1123 { 1124 struct mpls_dev *mdev; 1125 1126 mdev = mpls_dev_get(dev); 1127 if (!mdev) 1128 return 0; 1129 1130 return nla_total_size_64bit(sizeof(struct mpls_link_stats)); 1131 } 1132 1133 static int mpls_netconf_fill_devconf(struct sk_buff *skb, struct mpls_dev *mdev, 1134 u32 portid, u32 seq, int event, 1135 unsigned int flags, int type) 1136 { 1137 struct nlmsghdr *nlh; 1138 struct netconfmsg *ncm; 1139 bool all = false; 1140 1141 nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg), 1142 flags); 1143 if (!nlh) 1144 return -EMSGSIZE; 1145 1146 if (type == NETCONFA_ALL) 1147 all = true; 1148 1149 ncm = nlmsg_data(nlh); 1150 ncm->ncm_family = AF_MPLS; 1151 1152 if (nla_put_s32(skb, NETCONFA_IFINDEX, mdev->dev->ifindex) < 0) 1153 goto nla_put_failure; 1154 1155 if ((all || type == NETCONFA_INPUT) && 1156 nla_put_s32(skb, NETCONFA_INPUT, 1157 mdev->input_enabled) < 0) 1158 goto nla_put_failure; 1159 1160 nlmsg_end(skb, nlh); 1161 return 0; 1162 1163 nla_put_failure: 1164 nlmsg_cancel(skb, nlh); 1165 return -EMSGSIZE; 1166 } 1167 1168 static int mpls_netconf_msgsize_devconf(int type) 1169 { 1170 int size = NLMSG_ALIGN(sizeof(struct netconfmsg)) 1171 + nla_total_size(4); /* NETCONFA_IFINDEX */ 1172 bool all = false; 1173 1174 if (type == NETCONFA_ALL) 1175 all = true; 1176 1177 if (all || type == NETCONFA_INPUT) 1178 size += nla_total_size(4); 1179 1180 return size; 1181 } 1182 1183 static void mpls_netconf_notify_devconf(struct net *net, int event, 1184 int type, struct mpls_dev *mdev) 1185 { 1186 struct sk_buff *skb; 1187 int err = -ENOBUFS; 1188 1189 skb = nlmsg_new(mpls_netconf_msgsize_devconf(type), GFP_KERNEL); 1190 if (!skb) 1191 goto errout; 1192 1193 err = mpls_netconf_fill_devconf(skb, mdev, 0, 0, event, 0, type); 1194 if (err < 0) { 1195 /* -EMSGSIZE implies BUG in mpls_netconf_msgsize_devconf() */ 1196 WARN_ON(err == -EMSGSIZE); 1197 kfree_skb(skb); 1198 goto errout; 1199 } 1200 1201 rtnl_notify(skb, net, 0, RTNLGRP_MPLS_NETCONF, NULL, GFP_KERNEL); 1202 return; 1203 errout: 1204 if (err < 0) 1205 rtnl_set_sk_err(net, RTNLGRP_MPLS_NETCONF, err); 1206 } 1207 1208 static const struct nla_policy devconf_mpls_policy[NETCONFA_MAX + 1] = { 1209 [NETCONFA_IFINDEX] = { .len = sizeof(int) }, 1210 }; 1211 1212 static int mpls_netconf_get_devconf(struct sk_buff *in_skb, 1213 struct nlmsghdr *nlh, 1214 struct netlink_ext_ack *extack) 1215 { 1216 struct net *net = sock_net(in_skb->sk); 1217 struct nlattr *tb[NETCONFA_MAX + 1]; 1218 struct netconfmsg *ncm; 1219 struct net_device *dev; 1220 struct mpls_dev *mdev; 1221 struct sk_buff *skb; 1222 int ifindex; 1223 int err; 1224 1225 err = nlmsg_parse(nlh, sizeof(*ncm), tb, NETCONFA_MAX, 1226 devconf_mpls_policy, extack); 1227 if (err < 0) 1228 goto errout; 1229 1230 err = -EINVAL; 1231 if (!tb[NETCONFA_IFINDEX]) 1232 goto errout; 1233 1234 ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]); 1235 dev = __dev_get_by_index(net, ifindex); 1236 if (!dev) 1237 goto errout; 1238 1239 mdev = mpls_dev_get(dev); 1240 if (!mdev) 1241 goto errout; 1242 1243 err = -ENOBUFS; 1244 skb = nlmsg_new(mpls_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL); 1245 if (!skb) 1246 goto errout; 1247 1248 err = mpls_netconf_fill_devconf(skb, mdev, 1249 NETLINK_CB(in_skb).portid, 1250 nlh->nlmsg_seq, RTM_NEWNETCONF, 0, 1251 NETCONFA_ALL); 1252 if (err < 0) { 1253 /* -EMSGSIZE implies BUG in mpls_netconf_msgsize_devconf() */ 1254 WARN_ON(err == -EMSGSIZE); 1255 kfree_skb(skb); 1256 goto errout; 1257 } 1258 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid); 1259 errout: 1260 return err; 1261 } 1262 1263 static int mpls_netconf_dump_devconf(struct sk_buff *skb, 1264 struct netlink_callback *cb) 1265 { 1266 const struct nlmsghdr *nlh = cb->nlh; 1267 struct net *net = sock_net(skb->sk); 1268 struct hlist_head *head; 1269 struct net_device *dev; 1270 struct mpls_dev *mdev; 1271 int idx, s_idx; 1272 int h, s_h; 1273 1274 if (cb->strict_check) { 1275 struct netlink_ext_ack *extack = cb->extack; 1276 struct netconfmsg *ncm; 1277 1278 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ncm))) { 1279 NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf dump request"); 1280 return -EINVAL; 1281 } 1282 1283 if (nlmsg_attrlen(nlh, sizeof(*ncm))) { 1284 NL_SET_ERR_MSG_MOD(extack, "Invalid data after header in netconf dump request"); 1285 return -EINVAL; 1286 } 1287 } 1288 1289 s_h = cb->args[0]; 1290 s_idx = idx = cb->args[1]; 1291 1292 for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) { 1293 idx = 0; 1294 head = &net->dev_index_head[h]; 1295 rcu_read_lock(); 1296 cb->seq = net->dev_base_seq; 1297 hlist_for_each_entry_rcu(dev, head, index_hlist) { 1298 if (idx < s_idx) 1299 goto cont; 1300 mdev = mpls_dev_get(dev); 1301 if (!mdev) 1302 goto cont; 1303 if (mpls_netconf_fill_devconf(skb, mdev, 1304 NETLINK_CB(cb->skb).portid, 1305 nlh->nlmsg_seq, 1306 RTM_NEWNETCONF, 1307 NLM_F_MULTI, 1308 NETCONFA_ALL) < 0) { 1309 rcu_read_unlock(); 1310 goto done; 1311 } 1312 nl_dump_check_consistent(cb, nlmsg_hdr(skb)); 1313 cont: 1314 idx++; 1315 } 1316 rcu_read_unlock(); 1317 } 1318 done: 1319 cb->args[0] = h; 1320 cb->args[1] = idx; 1321 1322 return skb->len; 1323 } 1324 1325 #define MPLS_PERDEV_SYSCTL_OFFSET(field) \ 1326 (&((struct mpls_dev *)0)->field) 1327 1328 static int mpls_conf_proc(struct ctl_table *ctl, int write, 1329 void __user *buffer, 1330 size_t *lenp, loff_t *ppos) 1331 { 1332 int oval = *(int *)ctl->data; 1333 int ret = proc_dointvec(ctl, write, buffer, lenp, ppos); 1334 1335 if (write) { 1336 struct mpls_dev *mdev = ctl->extra1; 1337 int i = (int *)ctl->data - (int *)mdev; 1338 struct net *net = ctl->extra2; 1339 int val = *(int *)ctl->data; 1340 1341 if (i == offsetof(struct mpls_dev, input_enabled) && 1342 val != oval) { 1343 mpls_netconf_notify_devconf(net, RTM_NEWNETCONF, 1344 NETCONFA_INPUT, mdev); 1345 } 1346 } 1347 1348 return ret; 1349 } 1350 1351 static const struct ctl_table mpls_dev_table[] = { 1352 { 1353 .procname = "input", 1354 .maxlen = sizeof(int), 1355 .mode = 0644, 1356 .proc_handler = mpls_conf_proc, 1357 .data = MPLS_PERDEV_SYSCTL_OFFSET(input_enabled), 1358 }, 1359 { } 1360 }; 1361 1362 static int mpls_dev_sysctl_register(struct net_device *dev, 1363 struct mpls_dev *mdev) 1364 { 1365 char path[sizeof("net/mpls/conf/") + IFNAMSIZ]; 1366 struct net *net = dev_net(dev); 1367 struct ctl_table *table; 1368 int i; 1369 1370 table = kmemdup(&mpls_dev_table, sizeof(mpls_dev_table), GFP_KERNEL); 1371 if (!table) 1372 goto out; 1373 1374 /* Table data contains only offsets relative to the base of 1375 * the mdev at this point, so make them absolute. 1376 */ 1377 for (i = 0; i < ARRAY_SIZE(mpls_dev_table); i++) { 1378 table[i].data = (char *)mdev + (uintptr_t)table[i].data; 1379 table[i].extra1 = mdev; 1380 table[i].extra2 = net; 1381 } 1382 1383 snprintf(path, sizeof(path), "net/mpls/conf/%s", dev->name); 1384 1385 mdev->sysctl = register_net_sysctl(net, path, table); 1386 if (!mdev->sysctl) 1387 goto free; 1388 1389 mpls_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL, mdev); 1390 return 0; 1391 1392 free: 1393 kfree(table); 1394 out: 1395 return -ENOBUFS; 1396 } 1397 1398 static void mpls_dev_sysctl_unregister(struct net_device *dev, 1399 struct mpls_dev *mdev) 1400 { 1401 struct net *net = dev_net(dev); 1402 struct ctl_table *table; 1403 1404 table = mdev->sysctl->ctl_table_arg; 1405 unregister_net_sysctl_table(mdev->sysctl); 1406 kfree(table); 1407 1408 mpls_netconf_notify_devconf(net, RTM_DELNETCONF, 0, mdev); 1409 } 1410 1411 static struct mpls_dev *mpls_add_dev(struct net_device *dev) 1412 { 1413 struct mpls_dev *mdev; 1414 int err = -ENOMEM; 1415 int i; 1416 1417 ASSERT_RTNL(); 1418 1419 mdev = kzalloc(sizeof(*mdev), GFP_KERNEL); 1420 if (!mdev) 1421 return ERR_PTR(err); 1422 1423 mdev->stats = alloc_percpu(struct mpls_pcpu_stats); 1424 if (!mdev->stats) 1425 goto free; 1426 1427 for_each_possible_cpu(i) { 1428 struct mpls_pcpu_stats *mpls_stats; 1429 1430 mpls_stats = per_cpu_ptr(mdev->stats, i); 1431 u64_stats_init(&mpls_stats->syncp); 1432 } 1433 1434 mdev->dev = dev; 1435 1436 err = mpls_dev_sysctl_register(dev, mdev); 1437 if (err) 1438 goto free; 1439 1440 rcu_assign_pointer(dev->mpls_ptr, mdev); 1441 1442 return mdev; 1443 1444 free: 1445 free_percpu(mdev->stats); 1446 kfree(mdev); 1447 return ERR_PTR(err); 1448 } 1449 1450 static void mpls_dev_destroy_rcu(struct rcu_head *head) 1451 { 1452 struct mpls_dev *mdev = container_of(head, struct mpls_dev, rcu); 1453 1454 free_percpu(mdev->stats); 1455 kfree(mdev); 1456 } 1457 1458 static void mpls_ifdown(struct net_device *dev, int event) 1459 { 1460 struct mpls_route __rcu **platform_label; 1461 struct net *net = dev_net(dev); 1462 u8 alive, deleted; 1463 unsigned index; 1464 1465 platform_label = rtnl_dereference(net->mpls.platform_label); 1466 for (index = 0; index < net->mpls.platform_labels; index++) { 1467 struct mpls_route *rt = rtnl_dereference(platform_label[index]); 1468 1469 if (!rt) 1470 continue; 1471 1472 alive = 0; 1473 deleted = 0; 1474 change_nexthops(rt) { 1475 unsigned int nh_flags = nh->nh_flags; 1476 1477 if (rtnl_dereference(nh->nh_dev) != dev) 1478 goto next; 1479 1480 switch (event) { 1481 case NETDEV_DOWN: 1482 case NETDEV_UNREGISTER: 1483 nh_flags |= RTNH_F_DEAD; 1484 /* fall through */ 1485 case NETDEV_CHANGE: 1486 nh_flags |= RTNH_F_LINKDOWN; 1487 break; 1488 } 1489 if (event == NETDEV_UNREGISTER) 1490 RCU_INIT_POINTER(nh->nh_dev, NULL); 1491 1492 if (nh->nh_flags != nh_flags) 1493 WRITE_ONCE(nh->nh_flags, nh_flags); 1494 next: 1495 if (!(nh_flags & (RTNH_F_DEAD | RTNH_F_LINKDOWN))) 1496 alive++; 1497 if (!rtnl_dereference(nh->nh_dev)) 1498 deleted++; 1499 } endfor_nexthops(rt); 1500 1501 WRITE_ONCE(rt->rt_nhn_alive, alive); 1502 1503 /* if there are no more nexthops, delete the route */ 1504 if (event == NETDEV_UNREGISTER && deleted == rt->rt_nhn) 1505 mpls_route_update(net, index, NULL, NULL); 1506 } 1507 } 1508 1509 static void mpls_ifup(struct net_device *dev, unsigned int flags) 1510 { 1511 struct mpls_route __rcu **platform_label; 1512 struct net *net = dev_net(dev); 1513 unsigned index; 1514 u8 alive; 1515 1516 platform_label = rtnl_dereference(net->mpls.platform_label); 1517 for (index = 0; index < net->mpls.platform_labels; index++) { 1518 struct mpls_route *rt = rtnl_dereference(platform_label[index]); 1519 1520 if (!rt) 1521 continue; 1522 1523 alive = 0; 1524 change_nexthops(rt) { 1525 unsigned int nh_flags = nh->nh_flags; 1526 struct net_device *nh_dev = 1527 rtnl_dereference(nh->nh_dev); 1528 1529 if (!(nh_flags & flags)) { 1530 alive++; 1531 continue; 1532 } 1533 if (nh_dev != dev) 1534 continue; 1535 alive++; 1536 nh_flags &= ~flags; 1537 WRITE_ONCE(nh->nh_flags, nh_flags); 1538 } endfor_nexthops(rt); 1539 1540 WRITE_ONCE(rt->rt_nhn_alive, alive); 1541 } 1542 } 1543 1544 static int mpls_dev_notify(struct notifier_block *this, unsigned long event, 1545 void *ptr) 1546 { 1547 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 1548 struct mpls_dev *mdev; 1549 unsigned int flags; 1550 1551 if (event == NETDEV_REGISTER) { 1552 1553 /* For now just support Ethernet, IPGRE, IP6GRE, SIT and 1554 * IPIP devices 1555 */ 1556 if (dev->type == ARPHRD_ETHER || 1557 dev->type == ARPHRD_LOOPBACK || 1558 dev->type == ARPHRD_IPGRE || 1559 dev->type == ARPHRD_IP6GRE || 1560 dev->type == ARPHRD_SIT || 1561 dev->type == ARPHRD_TUNNEL) { 1562 mdev = mpls_add_dev(dev); 1563 if (IS_ERR(mdev)) 1564 return notifier_from_errno(PTR_ERR(mdev)); 1565 } 1566 return NOTIFY_OK; 1567 } 1568 1569 mdev = mpls_dev_get(dev); 1570 if (!mdev) 1571 return NOTIFY_OK; 1572 1573 switch (event) { 1574 case NETDEV_DOWN: 1575 mpls_ifdown(dev, event); 1576 break; 1577 case NETDEV_UP: 1578 flags = dev_get_flags(dev); 1579 if (flags & (IFF_RUNNING | IFF_LOWER_UP)) 1580 mpls_ifup(dev, RTNH_F_DEAD | RTNH_F_LINKDOWN); 1581 else 1582 mpls_ifup(dev, RTNH_F_DEAD); 1583 break; 1584 case NETDEV_CHANGE: 1585 flags = dev_get_flags(dev); 1586 if (flags & (IFF_RUNNING | IFF_LOWER_UP)) 1587 mpls_ifup(dev, RTNH_F_DEAD | RTNH_F_LINKDOWN); 1588 else 1589 mpls_ifdown(dev, event); 1590 break; 1591 case NETDEV_UNREGISTER: 1592 mpls_ifdown(dev, event); 1593 mdev = mpls_dev_get(dev); 1594 if (mdev) { 1595 mpls_dev_sysctl_unregister(dev, mdev); 1596 RCU_INIT_POINTER(dev->mpls_ptr, NULL); 1597 call_rcu(&mdev->rcu, mpls_dev_destroy_rcu); 1598 } 1599 break; 1600 case NETDEV_CHANGENAME: 1601 mdev = mpls_dev_get(dev); 1602 if (mdev) { 1603 int err; 1604 1605 mpls_dev_sysctl_unregister(dev, mdev); 1606 err = mpls_dev_sysctl_register(dev, mdev); 1607 if (err) 1608 return notifier_from_errno(err); 1609 } 1610 break; 1611 } 1612 return NOTIFY_OK; 1613 } 1614 1615 static struct notifier_block mpls_dev_notifier = { 1616 .notifier_call = mpls_dev_notify, 1617 }; 1618 1619 static int nla_put_via(struct sk_buff *skb, 1620 u8 table, const void *addr, int alen) 1621 { 1622 static const int table_to_family[NEIGH_NR_TABLES + 1] = { 1623 AF_INET, AF_INET6, AF_DECnet, AF_PACKET, 1624 }; 1625 struct nlattr *nla; 1626 struct rtvia *via; 1627 int family = AF_UNSPEC; 1628 1629 nla = nla_reserve(skb, RTA_VIA, alen + 2); 1630 if (!nla) 1631 return -EMSGSIZE; 1632 1633 if (table <= NEIGH_NR_TABLES) 1634 family = table_to_family[table]; 1635 1636 via = nla_data(nla); 1637 via->rtvia_family = family; 1638 memcpy(via->rtvia_addr, addr, alen); 1639 return 0; 1640 } 1641 1642 int nla_put_labels(struct sk_buff *skb, int attrtype, 1643 u8 labels, const u32 label[]) 1644 { 1645 struct nlattr *nla; 1646 struct mpls_shim_hdr *nla_label; 1647 bool bos; 1648 int i; 1649 nla = nla_reserve(skb, attrtype, labels*4); 1650 if (!nla) 1651 return -EMSGSIZE; 1652 1653 nla_label = nla_data(nla); 1654 bos = true; 1655 for (i = labels - 1; i >= 0; i--) { 1656 nla_label[i] = mpls_entry_encode(label[i], 0, 0, bos); 1657 bos = false; 1658 } 1659 1660 return 0; 1661 } 1662 EXPORT_SYMBOL_GPL(nla_put_labels); 1663 1664 int nla_get_labels(const struct nlattr *nla, u8 max_labels, u8 *labels, 1665 u32 label[], struct netlink_ext_ack *extack) 1666 { 1667 unsigned len = nla_len(nla); 1668 struct mpls_shim_hdr *nla_label; 1669 u8 nla_labels; 1670 bool bos; 1671 int i; 1672 1673 /* len needs to be an even multiple of 4 (the label size). Number 1674 * of labels is a u8 so check for overflow. 1675 */ 1676 if (len & 3 || len / 4 > 255) { 1677 NL_SET_ERR_MSG_ATTR(extack, nla, 1678 "Invalid length for labels attribute"); 1679 return -EINVAL; 1680 } 1681 1682 /* Limit the number of new labels allowed */ 1683 nla_labels = len/4; 1684 if (nla_labels > max_labels) { 1685 NL_SET_ERR_MSG(extack, "Too many labels"); 1686 return -EINVAL; 1687 } 1688 1689 /* when label == NULL, caller wants number of labels */ 1690 if (!label) 1691 goto out; 1692 1693 nla_label = nla_data(nla); 1694 bos = true; 1695 for (i = nla_labels - 1; i >= 0; i--, bos = false) { 1696 struct mpls_entry_decoded dec; 1697 dec = mpls_entry_decode(nla_label + i); 1698 1699 /* Ensure the bottom of stack flag is properly set 1700 * and ttl and tc are both clear. 1701 */ 1702 if (dec.ttl) { 1703 NL_SET_ERR_MSG_ATTR(extack, nla, 1704 "TTL in label must be 0"); 1705 return -EINVAL; 1706 } 1707 1708 if (dec.tc) { 1709 NL_SET_ERR_MSG_ATTR(extack, nla, 1710 "Traffic class in label must be 0"); 1711 return -EINVAL; 1712 } 1713 1714 if (dec.bos != bos) { 1715 NL_SET_BAD_ATTR(extack, nla); 1716 if (bos) { 1717 NL_SET_ERR_MSG(extack, 1718 "BOS bit must be set in first label"); 1719 } else { 1720 NL_SET_ERR_MSG(extack, 1721 "BOS bit can only be set in first label"); 1722 } 1723 return -EINVAL; 1724 } 1725 1726 switch (dec.label) { 1727 case MPLS_LABEL_IMPLNULL: 1728 /* RFC3032: This is a label that an LSR may 1729 * assign and distribute, but which never 1730 * actually appears in the encapsulation. 1731 */ 1732 NL_SET_ERR_MSG_ATTR(extack, nla, 1733 "Implicit NULL Label (3) can not be used in encapsulation"); 1734 return -EINVAL; 1735 } 1736 1737 label[i] = dec.label; 1738 } 1739 out: 1740 *labels = nla_labels; 1741 return 0; 1742 } 1743 EXPORT_SYMBOL_GPL(nla_get_labels); 1744 1745 static int rtm_to_route_config(struct sk_buff *skb, 1746 struct nlmsghdr *nlh, 1747 struct mpls_route_config *cfg, 1748 struct netlink_ext_ack *extack) 1749 { 1750 struct rtmsg *rtm; 1751 struct nlattr *tb[RTA_MAX+1]; 1752 int index; 1753 int err; 1754 1755 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_mpls_policy, 1756 extack); 1757 if (err < 0) 1758 goto errout; 1759 1760 err = -EINVAL; 1761 rtm = nlmsg_data(nlh); 1762 1763 if (rtm->rtm_family != AF_MPLS) { 1764 NL_SET_ERR_MSG(extack, "Invalid address family in rtmsg"); 1765 goto errout; 1766 } 1767 if (rtm->rtm_dst_len != 20) { 1768 NL_SET_ERR_MSG(extack, "rtm_dst_len must be 20 for MPLS"); 1769 goto errout; 1770 } 1771 if (rtm->rtm_src_len != 0) { 1772 NL_SET_ERR_MSG(extack, "rtm_src_len must be 0 for MPLS"); 1773 goto errout; 1774 } 1775 if (rtm->rtm_tos != 0) { 1776 NL_SET_ERR_MSG(extack, "rtm_tos must be 0 for MPLS"); 1777 goto errout; 1778 } 1779 if (rtm->rtm_table != RT_TABLE_MAIN) { 1780 NL_SET_ERR_MSG(extack, 1781 "MPLS only supports the main route table"); 1782 goto errout; 1783 } 1784 /* Any value is acceptable for rtm_protocol */ 1785 1786 /* As mpls uses destination specific addresses 1787 * (or source specific address in the case of multicast) 1788 * all addresses have universal scope. 1789 */ 1790 if (rtm->rtm_scope != RT_SCOPE_UNIVERSE) { 1791 NL_SET_ERR_MSG(extack, 1792 "Invalid route scope - MPLS only supports UNIVERSE"); 1793 goto errout; 1794 } 1795 if (rtm->rtm_type != RTN_UNICAST) { 1796 NL_SET_ERR_MSG(extack, 1797 "Invalid route type - MPLS only supports UNICAST"); 1798 goto errout; 1799 } 1800 if (rtm->rtm_flags != 0) { 1801 NL_SET_ERR_MSG(extack, "rtm_flags must be 0 for MPLS"); 1802 goto errout; 1803 } 1804 1805 cfg->rc_label = LABEL_NOT_SPECIFIED; 1806 cfg->rc_protocol = rtm->rtm_protocol; 1807 cfg->rc_via_table = MPLS_NEIGH_TABLE_UNSPEC; 1808 cfg->rc_ttl_propagate = MPLS_TTL_PROP_DEFAULT; 1809 cfg->rc_nlflags = nlh->nlmsg_flags; 1810 cfg->rc_nlinfo.portid = NETLINK_CB(skb).portid; 1811 cfg->rc_nlinfo.nlh = nlh; 1812 cfg->rc_nlinfo.nl_net = sock_net(skb->sk); 1813 1814 for (index = 0; index <= RTA_MAX; index++) { 1815 struct nlattr *nla = tb[index]; 1816 if (!nla) 1817 continue; 1818 1819 switch (index) { 1820 case RTA_OIF: 1821 cfg->rc_ifindex = nla_get_u32(nla); 1822 break; 1823 case RTA_NEWDST: 1824 if (nla_get_labels(nla, MAX_NEW_LABELS, 1825 &cfg->rc_output_labels, 1826 cfg->rc_output_label, extack)) 1827 goto errout; 1828 break; 1829 case RTA_DST: 1830 { 1831 u8 label_count; 1832 if (nla_get_labels(nla, 1, &label_count, 1833 &cfg->rc_label, extack)) 1834 goto errout; 1835 1836 if (!mpls_label_ok(cfg->rc_nlinfo.nl_net, 1837 &cfg->rc_label, extack)) 1838 goto errout; 1839 break; 1840 } 1841 case RTA_VIA: 1842 { 1843 if (nla_get_via(nla, &cfg->rc_via_alen, 1844 &cfg->rc_via_table, cfg->rc_via, 1845 extack)) 1846 goto errout; 1847 break; 1848 } 1849 case RTA_MULTIPATH: 1850 { 1851 cfg->rc_mp = nla_data(nla); 1852 cfg->rc_mp_len = nla_len(nla); 1853 break; 1854 } 1855 case RTA_TTL_PROPAGATE: 1856 { 1857 u8 ttl_propagate = nla_get_u8(nla); 1858 1859 if (ttl_propagate > 1) { 1860 NL_SET_ERR_MSG_ATTR(extack, nla, 1861 "RTA_TTL_PROPAGATE can only be 0 or 1"); 1862 goto errout; 1863 } 1864 cfg->rc_ttl_propagate = ttl_propagate ? 1865 MPLS_TTL_PROP_ENABLED : 1866 MPLS_TTL_PROP_DISABLED; 1867 break; 1868 } 1869 default: 1870 NL_SET_ERR_MSG_ATTR(extack, nla, "Unknown attribute"); 1871 /* Unsupported attribute */ 1872 goto errout; 1873 } 1874 } 1875 1876 err = 0; 1877 errout: 1878 return err; 1879 } 1880 1881 static int mpls_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh, 1882 struct netlink_ext_ack *extack) 1883 { 1884 struct mpls_route_config *cfg; 1885 int err; 1886 1887 cfg = kzalloc(sizeof(*cfg), GFP_KERNEL); 1888 if (!cfg) 1889 return -ENOMEM; 1890 1891 err = rtm_to_route_config(skb, nlh, cfg, extack); 1892 if (err < 0) 1893 goto out; 1894 1895 err = mpls_route_del(cfg, extack); 1896 out: 1897 kfree(cfg); 1898 1899 return err; 1900 } 1901 1902 1903 static int mpls_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh, 1904 struct netlink_ext_ack *extack) 1905 { 1906 struct mpls_route_config *cfg; 1907 int err; 1908 1909 cfg = kzalloc(sizeof(*cfg), GFP_KERNEL); 1910 if (!cfg) 1911 return -ENOMEM; 1912 1913 err = rtm_to_route_config(skb, nlh, cfg, extack); 1914 if (err < 0) 1915 goto out; 1916 1917 err = mpls_route_add(cfg, extack); 1918 out: 1919 kfree(cfg); 1920 1921 return err; 1922 } 1923 1924 static int mpls_dump_route(struct sk_buff *skb, u32 portid, u32 seq, int event, 1925 u32 label, struct mpls_route *rt, int flags) 1926 { 1927 struct net_device *dev; 1928 struct nlmsghdr *nlh; 1929 struct rtmsg *rtm; 1930 1931 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*rtm), flags); 1932 if (nlh == NULL) 1933 return -EMSGSIZE; 1934 1935 rtm = nlmsg_data(nlh); 1936 rtm->rtm_family = AF_MPLS; 1937 rtm->rtm_dst_len = 20; 1938 rtm->rtm_src_len = 0; 1939 rtm->rtm_tos = 0; 1940 rtm->rtm_table = RT_TABLE_MAIN; 1941 rtm->rtm_protocol = rt->rt_protocol; 1942 rtm->rtm_scope = RT_SCOPE_UNIVERSE; 1943 rtm->rtm_type = RTN_UNICAST; 1944 rtm->rtm_flags = 0; 1945 1946 if (nla_put_labels(skb, RTA_DST, 1, &label)) 1947 goto nla_put_failure; 1948 1949 if (rt->rt_ttl_propagate != MPLS_TTL_PROP_DEFAULT) { 1950 bool ttl_propagate = 1951 rt->rt_ttl_propagate == MPLS_TTL_PROP_ENABLED; 1952 1953 if (nla_put_u8(skb, RTA_TTL_PROPAGATE, 1954 ttl_propagate)) 1955 goto nla_put_failure; 1956 } 1957 if (rt->rt_nhn == 1) { 1958 const struct mpls_nh *nh = rt->rt_nh; 1959 1960 if (nh->nh_labels && 1961 nla_put_labels(skb, RTA_NEWDST, nh->nh_labels, 1962 nh->nh_label)) 1963 goto nla_put_failure; 1964 if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC && 1965 nla_put_via(skb, nh->nh_via_table, mpls_nh_via(rt, nh), 1966 nh->nh_via_alen)) 1967 goto nla_put_failure; 1968 dev = rtnl_dereference(nh->nh_dev); 1969 if (dev && nla_put_u32(skb, RTA_OIF, dev->ifindex)) 1970 goto nla_put_failure; 1971 if (nh->nh_flags & RTNH_F_LINKDOWN) 1972 rtm->rtm_flags |= RTNH_F_LINKDOWN; 1973 if (nh->nh_flags & RTNH_F_DEAD) 1974 rtm->rtm_flags |= RTNH_F_DEAD; 1975 } else { 1976 struct rtnexthop *rtnh; 1977 struct nlattr *mp; 1978 u8 linkdown = 0; 1979 u8 dead = 0; 1980 1981 mp = nla_nest_start(skb, RTA_MULTIPATH); 1982 if (!mp) 1983 goto nla_put_failure; 1984 1985 for_nexthops(rt) { 1986 dev = rtnl_dereference(nh->nh_dev); 1987 if (!dev) 1988 continue; 1989 1990 rtnh = nla_reserve_nohdr(skb, sizeof(*rtnh)); 1991 if (!rtnh) 1992 goto nla_put_failure; 1993 1994 rtnh->rtnh_ifindex = dev->ifindex; 1995 if (nh->nh_flags & RTNH_F_LINKDOWN) { 1996 rtnh->rtnh_flags |= RTNH_F_LINKDOWN; 1997 linkdown++; 1998 } 1999 if (nh->nh_flags & RTNH_F_DEAD) { 2000 rtnh->rtnh_flags |= RTNH_F_DEAD; 2001 dead++; 2002 } 2003 2004 if (nh->nh_labels && nla_put_labels(skb, RTA_NEWDST, 2005 nh->nh_labels, 2006 nh->nh_label)) 2007 goto nla_put_failure; 2008 if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC && 2009 nla_put_via(skb, nh->nh_via_table, 2010 mpls_nh_via(rt, nh), 2011 nh->nh_via_alen)) 2012 goto nla_put_failure; 2013 2014 /* length of rtnetlink header + attributes */ 2015 rtnh->rtnh_len = nlmsg_get_pos(skb) - (void *)rtnh; 2016 } endfor_nexthops(rt); 2017 2018 if (linkdown == rt->rt_nhn) 2019 rtm->rtm_flags |= RTNH_F_LINKDOWN; 2020 if (dead == rt->rt_nhn) 2021 rtm->rtm_flags |= RTNH_F_DEAD; 2022 2023 nla_nest_end(skb, mp); 2024 } 2025 2026 nlmsg_end(skb, nlh); 2027 return 0; 2028 2029 nla_put_failure: 2030 nlmsg_cancel(skb, nlh); 2031 return -EMSGSIZE; 2032 } 2033 2034 #if IS_ENABLED(CONFIG_INET) 2035 static int mpls_valid_fib_dump_req(struct net *net, const struct nlmsghdr *nlh, 2036 struct fib_dump_filter *filter, 2037 struct netlink_callback *cb) 2038 { 2039 return ip_valid_fib_dump_req(net, nlh, filter, cb); 2040 } 2041 #else 2042 static int mpls_valid_fib_dump_req(struct net *net, const struct nlmsghdr *nlh, 2043 struct fib_dump_filter *filter, 2044 struct netlink_callback *cb) 2045 { 2046 struct netlink_ext_ack *extack = cb->extack; 2047 struct nlattr *tb[RTA_MAX + 1]; 2048 struct rtmsg *rtm; 2049 int err, i; 2050 2051 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*rtm))) { 2052 NL_SET_ERR_MSG_MOD(extack, "Invalid header for FIB dump request"); 2053 return -EINVAL; 2054 } 2055 2056 rtm = nlmsg_data(nlh); 2057 if (rtm->rtm_dst_len || rtm->rtm_src_len || rtm->rtm_tos || 2058 rtm->rtm_table || rtm->rtm_scope || rtm->rtm_type || 2059 rtm->rtm_flags) { 2060 NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for FIB dump request"); 2061 return -EINVAL; 2062 } 2063 2064 if (rtm->rtm_protocol) { 2065 filter->protocol = rtm->rtm_protocol; 2066 filter->filter_set = 1; 2067 cb->answer_flags = NLM_F_DUMP_FILTERED; 2068 } 2069 2070 err = nlmsg_parse_strict(nlh, sizeof(*rtm), tb, RTA_MAX, 2071 rtm_mpls_policy, extack); 2072 if (err < 0) 2073 return err; 2074 2075 for (i = 0; i <= RTA_MAX; ++i) { 2076 int ifindex; 2077 2078 if (i == RTA_OIF) { 2079 ifindex = nla_get_u32(tb[i]); 2080 filter->dev = __dev_get_by_index(net, ifindex); 2081 if (!filter->dev) 2082 return -ENODEV; 2083 filter->filter_set = 1; 2084 } else if (tb[i]) { 2085 NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in dump request"); 2086 return -EINVAL; 2087 } 2088 } 2089 2090 return 0; 2091 } 2092 #endif 2093 2094 static bool mpls_rt_uses_dev(struct mpls_route *rt, 2095 const struct net_device *dev) 2096 { 2097 struct net_device *nh_dev; 2098 2099 if (rt->rt_nhn == 1) { 2100 struct mpls_nh *nh = rt->rt_nh; 2101 2102 nh_dev = rtnl_dereference(nh->nh_dev); 2103 if (dev == nh_dev) 2104 return true; 2105 } else { 2106 for_nexthops(rt) { 2107 nh_dev = rtnl_dereference(nh->nh_dev); 2108 if (nh_dev == dev) 2109 return true; 2110 } endfor_nexthops(rt); 2111 } 2112 2113 return false; 2114 } 2115 2116 static int mpls_dump_routes(struct sk_buff *skb, struct netlink_callback *cb) 2117 { 2118 const struct nlmsghdr *nlh = cb->nlh; 2119 struct net *net = sock_net(skb->sk); 2120 struct mpls_route __rcu **platform_label; 2121 struct fib_dump_filter filter = {}; 2122 unsigned int flags = NLM_F_MULTI; 2123 size_t platform_labels; 2124 unsigned int index; 2125 2126 ASSERT_RTNL(); 2127 2128 if (cb->strict_check) { 2129 int err; 2130 2131 err = mpls_valid_fib_dump_req(net, nlh, &filter, cb); 2132 if (err < 0) 2133 return err; 2134 2135 /* for MPLS, there is only 1 table with fixed type and flags. 2136 * If either are set in the filter then return nothing. 2137 */ 2138 if ((filter.table_id && filter.table_id != RT_TABLE_MAIN) || 2139 (filter.rt_type && filter.rt_type != RTN_UNICAST) || 2140 filter.flags) 2141 return skb->len; 2142 } 2143 2144 index = cb->args[0]; 2145 if (index < MPLS_LABEL_FIRST_UNRESERVED) 2146 index = MPLS_LABEL_FIRST_UNRESERVED; 2147 2148 platform_label = rtnl_dereference(net->mpls.platform_label); 2149 platform_labels = net->mpls.platform_labels; 2150 2151 if (filter.filter_set) 2152 flags |= NLM_F_DUMP_FILTERED; 2153 2154 for (; index < platform_labels; index++) { 2155 struct mpls_route *rt; 2156 2157 rt = rtnl_dereference(platform_label[index]); 2158 if (!rt) 2159 continue; 2160 2161 if ((filter.dev && !mpls_rt_uses_dev(rt, filter.dev)) || 2162 (filter.protocol && rt->rt_protocol != filter.protocol)) 2163 continue; 2164 2165 if (mpls_dump_route(skb, NETLINK_CB(cb->skb).portid, 2166 cb->nlh->nlmsg_seq, RTM_NEWROUTE, 2167 index, rt, flags) < 0) 2168 break; 2169 } 2170 cb->args[0] = index; 2171 2172 return skb->len; 2173 } 2174 2175 static inline size_t lfib_nlmsg_size(struct mpls_route *rt) 2176 { 2177 size_t payload = 2178 NLMSG_ALIGN(sizeof(struct rtmsg)) 2179 + nla_total_size(4) /* RTA_DST */ 2180 + nla_total_size(1); /* RTA_TTL_PROPAGATE */ 2181 2182 if (rt->rt_nhn == 1) { 2183 struct mpls_nh *nh = rt->rt_nh; 2184 2185 if (nh->nh_dev) 2186 payload += nla_total_size(4); /* RTA_OIF */ 2187 if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC) /* RTA_VIA */ 2188 payload += nla_total_size(2 + nh->nh_via_alen); 2189 if (nh->nh_labels) /* RTA_NEWDST */ 2190 payload += nla_total_size(nh->nh_labels * 4); 2191 } else { 2192 /* each nexthop is packed in an attribute */ 2193 size_t nhsize = 0; 2194 2195 for_nexthops(rt) { 2196 if (!rtnl_dereference(nh->nh_dev)) 2197 continue; 2198 nhsize += nla_total_size(sizeof(struct rtnexthop)); 2199 /* RTA_VIA */ 2200 if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC) 2201 nhsize += nla_total_size(2 + nh->nh_via_alen); 2202 if (nh->nh_labels) 2203 nhsize += nla_total_size(nh->nh_labels * 4); 2204 } endfor_nexthops(rt); 2205 /* nested attribute */ 2206 payload += nla_total_size(nhsize); 2207 } 2208 2209 return payload; 2210 } 2211 2212 static void rtmsg_lfib(int event, u32 label, struct mpls_route *rt, 2213 struct nlmsghdr *nlh, struct net *net, u32 portid, 2214 unsigned int nlm_flags) 2215 { 2216 struct sk_buff *skb; 2217 u32 seq = nlh ? nlh->nlmsg_seq : 0; 2218 int err = -ENOBUFS; 2219 2220 skb = nlmsg_new(lfib_nlmsg_size(rt), GFP_KERNEL); 2221 if (skb == NULL) 2222 goto errout; 2223 2224 err = mpls_dump_route(skb, portid, seq, event, label, rt, nlm_flags); 2225 if (err < 0) { 2226 /* -EMSGSIZE implies BUG in lfib_nlmsg_size */ 2227 WARN_ON(err == -EMSGSIZE); 2228 kfree_skb(skb); 2229 goto errout; 2230 } 2231 rtnl_notify(skb, net, portid, RTNLGRP_MPLS_ROUTE, nlh, GFP_KERNEL); 2232 2233 return; 2234 errout: 2235 if (err < 0) 2236 rtnl_set_sk_err(net, RTNLGRP_MPLS_ROUTE, err); 2237 } 2238 2239 static int mpls_getroute(struct sk_buff *in_skb, struct nlmsghdr *in_nlh, 2240 struct netlink_ext_ack *extack) 2241 { 2242 struct net *net = sock_net(in_skb->sk); 2243 u32 portid = NETLINK_CB(in_skb).portid; 2244 u32 in_label = LABEL_NOT_SPECIFIED; 2245 struct nlattr *tb[RTA_MAX + 1]; 2246 u32 labels[MAX_NEW_LABELS]; 2247 struct mpls_shim_hdr *hdr; 2248 unsigned int hdr_size = 0; 2249 struct net_device *dev; 2250 struct mpls_route *rt; 2251 struct rtmsg *rtm, *r; 2252 struct nlmsghdr *nlh; 2253 struct sk_buff *skb; 2254 struct mpls_nh *nh; 2255 u8 n_labels; 2256 int err; 2257 2258 err = nlmsg_parse(in_nlh, sizeof(*rtm), tb, RTA_MAX, 2259 rtm_mpls_policy, extack); 2260 if (err < 0) 2261 goto errout; 2262 2263 rtm = nlmsg_data(in_nlh); 2264 2265 if (tb[RTA_DST]) { 2266 u8 label_count; 2267 2268 if (nla_get_labels(tb[RTA_DST], 1, &label_count, 2269 &in_label, extack)) { 2270 err = -EINVAL; 2271 goto errout; 2272 } 2273 2274 if (!mpls_label_ok(net, &in_label, extack)) { 2275 err = -EINVAL; 2276 goto errout; 2277 } 2278 } 2279 2280 rt = mpls_route_input_rcu(net, in_label); 2281 if (!rt) { 2282 err = -ENETUNREACH; 2283 goto errout; 2284 } 2285 2286 if (rtm->rtm_flags & RTM_F_FIB_MATCH) { 2287 skb = nlmsg_new(lfib_nlmsg_size(rt), GFP_KERNEL); 2288 if (!skb) { 2289 err = -ENOBUFS; 2290 goto errout; 2291 } 2292 2293 err = mpls_dump_route(skb, portid, in_nlh->nlmsg_seq, 2294 RTM_NEWROUTE, in_label, rt, 0); 2295 if (err < 0) { 2296 /* -EMSGSIZE implies BUG in lfib_nlmsg_size */ 2297 WARN_ON(err == -EMSGSIZE); 2298 goto errout_free; 2299 } 2300 2301 return rtnl_unicast(skb, net, portid); 2302 } 2303 2304 if (tb[RTA_NEWDST]) { 2305 if (nla_get_labels(tb[RTA_NEWDST], MAX_NEW_LABELS, &n_labels, 2306 labels, extack) != 0) { 2307 err = -EINVAL; 2308 goto errout; 2309 } 2310 2311 hdr_size = n_labels * sizeof(struct mpls_shim_hdr); 2312 } 2313 2314 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); 2315 if (!skb) { 2316 err = -ENOBUFS; 2317 goto errout; 2318 } 2319 2320 skb->protocol = htons(ETH_P_MPLS_UC); 2321 2322 if (hdr_size) { 2323 bool bos; 2324 int i; 2325 2326 if (skb_cow(skb, hdr_size)) { 2327 err = -ENOBUFS; 2328 goto errout_free; 2329 } 2330 2331 skb_reserve(skb, hdr_size); 2332 skb_push(skb, hdr_size); 2333 skb_reset_network_header(skb); 2334 2335 /* Push new labels */ 2336 hdr = mpls_hdr(skb); 2337 bos = true; 2338 for (i = n_labels - 1; i >= 0; i--) { 2339 hdr[i] = mpls_entry_encode(labels[i], 2340 1, 0, bos); 2341 bos = false; 2342 } 2343 } 2344 2345 nh = mpls_select_multipath(rt, skb); 2346 if (!nh) { 2347 err = -ENETUNREACH; 2348 goto errout_free; 2349 } 2350 2351 if (hdr_size) { 2352 skb_pull(skb, hdr_size); 2353 skb_reset_network_header(skb); 2354 } 2355 2356 nlh = nlmsg_put(skb, portid, in_nlh->nlmsg_seq, 2357 RTM_NEWROUTE, sizeof(*r), 0); 2358 if (!nlh) { 2359 err = -EMSGSIZE; 2360 goto errout_free; 2361 } 2362 2363 r = nlmsg_data(nlh); 2364 r->rtm_family = AF_MPLS; 2365 r->rtm_dst_len = 20; 2366 r->rtm_src_len = 0; 2367 r->rtm_table = RT_TABLE_MAIN; 2368 r->rtm_type = RTN_UNICAST; 2369 r->rtm_scope = RT_SCOPE_UNIVERSE; 2370 r->rtm_protocol = rt->rt_protocol; 2371 r->rtm_flags = 0; 2372 2373 if (nla_put_labels(skb, RTA_DST, 1, &in_label)) 2374 goto nla_put_failure; 2375 2376 if (nh->nh_labels && 2377 nla_put_labels(skb, RTA_NEWDST, nh->nh_labels, 2378 nh->nh_label)) 2379 goto nla_put_failure; 2380 2381 if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC && 2382 nla_put_via(skb, nh->nh_via_table, mpls_nh_via(rt, nh), 2383 nh->nh_via_alen)) 2384 goto nla_put_failure; 2385 dev = rtnl_dereference(nh->nh_dev); 2386 if (dev && nla_put_u32(skb, RTA_OIF, dev->ifindex)) 2387 goto nla_put_failure; 2388 2389 nlmsg_end(skb, nlh); 2390 2391 err = rtnl_unicast(skb, net, portid); 2392 errout: 2393 return err; 2394 2395 nla_put_failure: 2396 nlmsg_cancel(skb, nlh); 2397 err = -EMSGSIZE; 2398 errout_free: 2399 kfree_skb(skb); 2400 return err; 2401 } 2402 2403 static int resize_platform_label_table(struct net *net, size_t limit) 2404 { 2405 size_t size = sizeof(struct mpls_route *) * limit; 2406 size_t old_limit; 2407 size_t cp_size; 2408 struct mpls_route __rcu **labels = NULL, **old; 2409 struct mpls_route *rt0 = NULL, *rt2 = NULL; 2410 unsigned index; 2411 2412 if (size) { 2413 labels = kvzalloc(size, GFP_KERNEL); 2414 if (!labels) 2415 goto nolabels; 2416 } 2417 2418 /* In case the predefined labels need to be populated */ 2419 if (limit > MPLS_LABEL_IPV4NULL) { 2420 struct net_device *lo = net->loopback_dev; 2421 rt0 = mpls_rt_alloc(1, lo->addr_len, 0); 2422 if (IS_ERR(rt0)) 2423 goto nort0; 2424 RCU_INIT_POINTER(rt0->rt_nh->nh_dev, lo); 2425 rt0->rt_protocol = RTPROT_KERNEL; 2426 rt0->rt_payload_type = MPT_IPV4; 2427 rt0->rt_ttl_propagate = MPLS_TTL_PROP_DEFAULT; 2428 rt0->rt_nh->nh_via_table = NEIGH_LINK_TABLE; 2429 rt0->rt_nh->nh_via_alen = lo->addr_len; 2430 memcpy(__mpls_nh_via(rt0, rt0->rt_nh), lo->dev_addr, 2431 lo->addr_len); 2432 } 2433 if (limit > MPLS_LABEL_IPV6NULL) { 2434 struct net_device *lo = net->loopback_dev; 2435 rt2 = mpls_rt_alloc(1, lo->addr_len, 0); 2436 if (IS_ERR(rt2)) 2437 goto nort2; 2438 RCU_INIT_POINTER(rt2->rt_nh->nh_dev, lo); 2439 rt2->rt_protocol = RTPROT_KERNEL; 2440 rt2->rt_payload_type = MPT_IPV6; 2441 rt2->rt_ttl_propagate = MPLS_TTL_PROP_DEFAULT; 2442 rt2->rt_nh->nh_via_table = NEIGH_LINK_TABLE; 2443 rt2->rt_nh->nh_via_alen = lo->addr_len; 2444 memcpy(__mpls_nh_via(rt2, rt2->rt_nh), lo->dev_addr, 2445 lo->addr_len); 2446 } 2447 2448 rtnl_lock(); 2449 /* Remember the original table */ 2450 old = rtnl_dereference(net->mpls.platform_label); 2451 old_limit = net->mpls.platform_labels; 2452 2453 /* Free any labels beyond the new table */ 2454 for (index = limit; index < old_limit; index++) 2455 mpls_route_update(net, index, NULL, NULL); 2456 2457 /* Copy over the old labels */ 2458 cp_size = size; 2459 if (old_limit < limit) 2460 cp_size = old_limit * sizeof(struct mpls_route *); 2461 2462 memcpy(labels, old, cp_size); 2463 2464 /* If needed set the predefined labels */ 2465 if ((old_limit <= MPLS_LABEL_IPV6NULL) && 2466 (limit > MPLS_LABEL_IPV6NULL)) { 2467 RCU_INIT_POINTER(labels[MPLS_LABEL_IPV6NULL], rt2); 2468 rt2 = NULL; 2469 } 2470 2471 if ((old_limit <= MPLS_LABEL_IPV4NULL) && 2472 (limit > MPLS_LABEL_IPV4NULL)) { 2473 RCU_INIT_POINTER(labels[MPLS_LABEL_IPV4NULL], rt0); 2474 rt0 = NULL; 2475 } 2476 2477 /* Update the global pointers */ 2478 net->mpls.platform_labels = limit; 2479 rcu_assign_pointer(net->mpls.platform_label, labels); 2480 2481 rtnl_unlock(); 2482 2483 mpls_rt_free(rt2); 2484 mpls_rt_free(rt0); 2485 2486 if (old) { 2487 synchronize_rcu(); 2488 kvfree(old); 2489 } 2490 return 0; 2491 2492 nort2: 2493 mpls_rt_free(rt0); 2494 nort0: 2495 kvfree(labels); 2496 nolabels: 2497 return -ENOMEM; 2498 } 2499 2500 static int mpls_platform_labels(struct ctl_table *table, int write, 2501 void __user *buffer, size_t *lenp, loff_t *ppos) 2502 { 2503 struct net *net = table->data; 2504 int platform_labels = net->mpls.platform_labels; 2505 int ret; 2506 struct ctl_table tmp = { 2507 .procname = table->procname, 2508 .data = &platform_labels, 2509 .maxlen = sizeof(int), 2510 .mode = table->mode, 2511 .extra1 = &zero, 2512 .extra2 = &label_limit, 2513 }; 2514 2515 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos); 2516 2517 if (write && ret == 0) 2518 ret = resize_platform_label_table(net, platform_labels); 2519 2520 return ret; 2521 } 2522 2523 #define MPLS_NS_SYSCTL_OFFSET(field) \ 2524 (&((struct net *)0)->field) 2525 2526 static const struct ctl_table mpls_table[] = { 2527 { 2528 .procname = "platform_labels", 2529 .data = NULL, 2530 .maxlen = sizeof(int), 2531 .mode = 0644, 2532 .proc_handler = mpls_platform_labels, 2533 }, 2534 { 2535 .procname = "ip_ttl_propagate", 2536 .data = MPLS_NS_SYSCTL_OFFSET(mpls.ip_ttl_propagate), 2537 .maxlen = sizeof(int), 2538 .mode = 0644, 2539 .proc_handler = proc_dointvec_minmax, 2540 .extra1 = &zero, 2541 .extra2 = &one, 2542 }, 2543 { 2544 .procname = "default_ttl", 2545 .data = MPLS_NS_SYSCTL_OFFSET(mpls.default_ttl), 2546 .maxlen = sizeof(int), 2547 .mode = 0644, 2548 .proc_handler = proc_dointvec_minmax, 2549 .extra1 = &one, 2550 .extra2 = &ttl_max, 2551 }, 2552 { } 2553 }; 2554 2555 static int mpls_net_init(struct net *net) 2556 { 2557 struct ctl_table *table; 2558 int i; 2559 2560 net->mpls.platform_labels = 0; 2561 net->mpls.platform_label = NULL; 2562 net->mpls.ip_ttl_propagate = 1; 2563 net->mpls.default_ttl = 255; 2564 2565 table = kmemdup(mpls_table, sizeof(mpls_table), GFP_KERNEL); 2566 if (table == NULL) 2567 return -ENOMEM; 2568 2569 /* Table data contains only offsets relative to the base of 2570 * the mdev at this point, so make them absolute. 2571 */ 2572 for (i = 0; i < ARRAY_SIZE(mpls_table) - 1; i++) 2573 table[i].data = (char *)net + (uintptr_t)table[i].data; 2574 2575 net->mpls.ctl = register_net_sysctl(net, "net/mpls", table); 2576 if (net->mpls.ctl == NULL) { 2577 kfree(table); 2578 return -ENOMEM; 2579 } 2580 2581 return 0; 2582 } 2583 2584 static void mpls_net_exit(struct net *net) 2585 { 2586 struct mpls_route __rcu **platform_label; 2587 size_t platform_labels; 2588 struct ctl_table *table; 2589 unsigned int index; 2590 2591 table = net->mpls.ctl->ctl_table_arg; 2592 unregister_net_sysctl_table(net->mpls.ctl); 2593 kfree(table); 2594 2595 /* An rcu grace period has passed since there was a device in 2596 * the network namespace (and thus the last in flight packet) 2597 * left this network namespace. This is because 2598 * unregister_netdevice_many and netdev_run_todo has completed 2599 * for each network device that was in this network namespace. 2600 * 2601 * As such no additional rcu synchronization is necessary when 2602 * freeing the platform_label table. 2603 */ 2604 rtnl_lock(); 2605 platform_label = rtnl_dereference(net->mpls.platform_label); 2606 platform_labels = net->mpls.platform_labels; 2607 for (index = 0; index < platform_labels; index++) { 2608 struct mpls_route *rt = rtnl_dereference(platform_label[index]); 2609 RCU_INIT_POINTER(platform_label[index], NULL); 2610 mpls_notify_route(net, index, rt, NULL, NULL); 2611 mpls_rt_free(rt); 2612 } 2613 rtnl_unlock(); 2614 2615 kvfree(platform_label); 2616 } 2617 2618 static struct pernet_operations mpls_net_ops = { 2619 .init = mpls_net_init, 2620 .exit = mpls_net_exit, 2621 }; 2622 2623 static struct rtnl_af_ops mpls_af_ops __read_mostly = { 2624 .family = AF_MPLS, 2625 .fill_stats_af = mpls_fill_stats_af, 2626 .get_stats_af_size = mpls_get_stats_af_size, 2627 }; 2628 2629 static int __init mpls_init(void) 2630 { 2631 int err; 2632 2633 BUILD_BUG_ON(sizeof(struct mpls_shim_hdr) != 4); 2634 2635 err = register_pernet_subsys(&mpls_net_ops); 2636 if (err) 2637 goto out; 2638 2639 err = register_netdevice_notifier(&mpls_dev_notifier); 2640 if (err) 2641 goto out_unregister_pernet; 2642 2643 dev_add_pack(&mpls_packet_type); 2644 2645 rtnl_af_register(&mpls_af_ops); 2646 2647 rtnl_register_module(THIS_MODULE, PF_MPLS, RTM_NEWROUTE, 2648 mpls_rtm_newroute, NULL, 0); 2649 rtnl_register_module(THIS_MODULE, PF_MPLS, RTM_DELROUTE, 2650 mpls_rtm_delroute, NULL, 0); 2651 rtnl_register_module(THIS_MODULE, PF_MPLS, RTM_GETROUTE, 2652 mpls_getroute, mpls_dump_routes, 0); 2653 rtnl_register_module(THIS_MODULE, PF_MPLS, RTM_GETNETCONF, 2654 mpls_netconf_get_devconf, 2655 mpls_netconf_dump_devconf, 0); 2656 err = ipgre_tunnel_encap_add_mpls_ops(); 2657 if (err) 2658 pr_err("Can't add mpls over gre tunnel ops\n"); 2659 2660 err = 0; 2661 out: 2662 return err; 2663 2664 out_unregister_pernet: 2665 unregister_pernet_subsys(&mpls_net_ops); 2666 goto out; 2667 } 2668 module_init(mpls_init); 2669 2670 static void __exit mpls_exit(void) 2671 { 2672 rtnl_unregister_all(PF_MPLS); 2673 rtnl_af_unregister(&mpls_af_ops); 2674 dev_remove_pack(&mpls_packet_type); 2675 unregister_netdevice_notifier(&mpls_dev_notifier); 2676 unregister_pernet_subsys(&mpls_net_ops); 2677 ipgre_tunnel_encap_del_mpls_ops(); 2678 } 2679 module_exit(mpls_exit); 2680 2681 MODULE_DESCRIPTION("MultiProtocol Label Switching"); 2682 MODULE_LICENSE("GPL v2"); 2683 MODULE_ALIAS_NETPROTO(PF_MPLS); 2684