1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* GTP according to GSM TS 09.60 / 3GPP TS 29.060 3 * 4 * (C) 2012-2014 by sysmocom - s.f.m.c. GmbH 5 * (C) 2016 by Pablo Neira Ayuso <pablo@netfilter.org> 6 * 7 * Author: Harald Welte <hwelte@sysmocom.de> 8 * Pablo Neira Ayuso <pablo@netfilter.org> 9 * Andreas Schultz <aschultz@travelping.com> 10 */ 11 12 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 13 14 #include <linux/module.h> 15 #include <linux/skbuff.h> 16 #include <linux/udp.h> 17 #include <linux/rculist.h> 18 #include <linux/jhash.h> 19 #include <linux/if_tunnel.h> 20 #include <linux/net.h> 21 #include <linux/file.h> 22 #include <linux/gtp.h> 23 24 #include <net/net_namespace.h> 25 #include <net/protocol.h> 26 #include <net/ip.h> 27 #include <net/udp.h> 28 #include <net/udp_tunnel.h> 29 #include <net/icmp.h> 30 #include <net/xfrm.h> 31 #include <net/genetlink.h> 32 #include <net/netns/generic.h> 33 #include <net/gtp.h> 34 35 /* An active session for the subscriber. */ 36 struct pdp_ctx { 37 struct hlist_node hlist_tid; 38 struct hlist_node hlist_addr; 39 40 union { 41 u64 tid; 42 struct { 43 u64 tid; 44 u16 flow; 45 } v0; 46 struct { 47 u32 i_tei; 48 u32 o_tei; 49 } v1; 50 } u; 51 u8 gtp_version; 52 u16 af; 53 54 struct in_addr ms_addr_ip4; 55 struct in_addr peer_addr_ip4; 56 57 struct sock *sk; 58 struct net_device *dev; 59 60 atomic_t tx_seq; 61 struct rcu_head rcu_head; 62 }; 63 64 /* One instance of the GTP device. */ 65 struct gtp_dev { 66 struct list_head list; 67 68 struct sock *sk0; 69 struct sock *sk1u; 70 71 struct net_device *dev; 72 73 unsigned int role; 74 unsigned int hash_size; 75 struct hlist_head *tid_hash; 76 struct hlist_head *addr_hash; 77 }; 78 79 static unsigned int gtp_net_id __read_mostly; 80 81 struct gtp_net { 82 struct list_head gtp_dev_list; 83 }; 84 85 static u32 gtp_h_initval; 86 87 static void pdp_context_delete(struct pdp_ctx *pctx); 88 89 static inline u32 gtp0_hashfn(u64 tid) 90 { 91 u32 *tid32 = (u32 *) &tid; 92 return jhash_2words(tid32[0], tid32[1], gtp_h_initval); 93 } 94 95 static inline u32 gtp1u_hashfn(u32 tid) 96 { 97 return jhash_1word(tid, gtp_h_initval); 98 } 99 100 static inline u32 ipv4_hashfn(__be32 ip) 101 { 102 return jhash_1word((__force u32)ip, gtp_h_initval); 103 } 104 105 /* Resolve a PDP context structure based on the 64bit TID. */ 106 static struct pdp_ctx *gtp0_pdp_find(struct gtp_dev *gtp, u64 tid) 107 { 108 struct hlist_head *head; 109 struct pdp_ctx *pdp; 110 111 head = >p->tid_hash[gtp0_hashfn(tid) % gtp->hash_size]; 112 113 hlist_for_each_entry_rcu(pdp, head, hlist_tid) { 114 if (pdp->gtp_version == GTP_V0 && 115 pdp->u.v0.tid == tid) 116 return pdp; 117 } 118 return NULL; 119 } 120 121 /* Resolve a PDP context structure based on the 32bit TEI. */ 122 static struct pdp_ctx *gtp1_pdp_find(struct gtp_dev *gtp, u32 tid) 123 { 124 struct hlist_head *head; 125 struct pdp_ctx *pdp; 126 127 head = >p->tid_hash[gtp1u_hashfn(tid) % gtp->hash_size]; 128 129 hlist_for_each_entry_rcu(pdp, head, hlist_tid) { 130 if (pdp->gtp_version == GTP_V1 && 131 pdp->u.v1.i_tei == tid) 132 return pdp; 133 } 134 return NULL; 135 } 136 137 /* Resolve a PDP context based on IPv4 address of MS. */ 138 static struct pdp_ctx *ipv4_pdp_find(struct gtp_dev *gtp, __be32 ms_addr) 139 { 140 struct hlist_head *head; 141 struct pdp_ctx *pdp; 142 143 head = >p->addr_hash[ipv4_hashfn(ms_addr) % gtp->hash_size]; 144 145 hlist_for_each_entry_rcu(pdp, head, hlist_addr) { 146 if (pdp->af == AF_INET && 147 pdp->ms_addr_ip4.s_addr == ms_addr) 148 return pdp; 149 } 150 151 return NULL; 152 } 153 154 static bool gtp_check_ms_ipv4(struct sk_buff *skb, struct pdp_ctx *pctx, 155 unsigned int hdrlen, unsigned int role) 156 { 157 struct iphdr *iph; 158 159 if (!pskb_may_pull(skb, hdrlen + sizeof(struct iphdr))) 160 return false; 161 162 iph = (struct iphdr *)(skb->data + hdrlen); 163 164 if (role == GTP_ROLE_SGSN) 165 return iph->daddr == pctx->ms_addr_ip4.s_addr; 166 else 167 return iph->saddr == pctx->ms_addr_ip4.s_addr; 168 } 169 170 /* Check if the inner IP address in this packet is assigned to any 171 * existing mobile subscriber. 172 */ 173 static bool gtp_check_ms(struct sk_buff *skb, struct pdp_ctx *pctx, 174 unsigned int hdrlen, unsigned int role) 175 { 176 switch (ntohs(skb->protocol)) { 177 case ETH_P_IP: 178 return gtp_check_ms_ipv4(skb, pctx, hdrlen, role); 179 } 180 return false; 181 } 182 183 static int gtp_rx(struct pdp_ctx *pctx, struct sk_buff *skb, 184 unsigned int hdrlen, unsigned int role) 185 { 186 struct pcpu_sw_netstats *stats; 187 188 if (!gtp_check_ms(skb, pctx, hdrlen, role)) { 189 netdev_dbg(pctx->dev, "No PDP ctx for this MS\n"); 190 return 1; 191 } 192 193 /* Get rid of the GTP + UDP headers. */ 194 if (iptunnel_pull_header(skb, hdrlen, skb->protocol, 195 !net_eq(sock_net(pctx->sk), dev_net(pctx->dev)))) 196 return -1; 197 198 netdev_dbg(pctx->dev, "forwarding packet from GGSN to uplink\n"); 199 200 /* Now that the UDP and the GTP header have been removed, set up the 201 * new network header. This is required by the upper layer to 202 * calculate the transport header. 203 */ 204 skb_reset_network_header(skb); 205 206 skb->dev = pctx->dev; 207 208 stats = this_cpu_ptr(pctx->dev->tstats); 209 u64_stats_update_begin(&stats->syncp); 210 stats->rx_packets++; 211 stats->rx_bytes += skb->len; 212 u64_stats_update_end(&stats->syncp); 213 214 netif_rx(skb); 215 return 0; 216 } 217 218 /* 1 means pass up to the stack, -1 means drop and 0 means decapsulated. */ 219 static int gtp0_udp_encap_recv(struct gtp_dev *gtp, struct sk_buff *skb) 220 { 221 unsigned int hdrlen = sizeof(struct udphdr) + 222 sizeof(struct gtp0_header); 223 struct gtp0_header *gtp0; 224 struct pdp_ctx *pctx; 225 226 if (!pskb_may_pull(skb, hdrlen)) 227 return -1; 228 229 gtp0 = (struct gtp0_header *)(skb->data + sizeof(struct udphdr)); 230 231 if ((gtp0->flags >> 5) != GTP_V0) 232 return 1; 233 234 if (gtp0->type != GTP_TPDU) 235 return 1; 236 237 pctx = gtp0_pdp_find(gtp, be64_to_cpu(gtp0->tid)); 238 if (!pctx) { 239 netdev_dbg(gtp->dev, "No PDP ctx to decap skb=%p\n", skb); 240 return 1; 241 } 242 243 return gtp_rx(pctx, skb, hdrlen, gtp->role); 244 } 245 246 static int gtp1u_udp_encap_recv(struct gtp_dev *gtp, struct sk_buff *skb) 247 { 248 unsigned int hdrlen = sizeof(struct udphdr) + 249 sizeof(struct gtp1_header); 250 struct gtp1_header *gtp1; 251 struct pdp_ctx *pctx; 252 253 if (!pskb_may_pull(skb, hdrlen)) 254 return -1; 255 256 gtp1 = (struct gtp1_header *)(skb->data + sizeof(struct udphdr)); 257 258 if ((gtp1->flags >> 5) != GTP_V1) 259 return 1; 260 261 if (gtp1->type != GTP_TPDU) 262 return 1; 263 264 /* From 29.060: "This field shall be present if and only if any one or 265 * more of the S, PN and E flags are set.". 266 * 267 * If any of the bit is set, then the remaining ones also have to be 268 * set. 269 */ 270 if (gtp1->flags & GTP1_F_MASK) 271 hdrlen += 4; 272 273 /* Make sure the header is larger enough, including extensions. */ 274 if (!pskb_may_pull(skb, hdrlen)) 275 return -1; 276 277 gtp1 = (struct gtp1_header *)(skb->data + sizeof(struct udphdr)); 278 279 pctx = gtp1_pdp_find(gtp, ntohl(gtp1->tid)); 280 if (!pctx) { 281 netdev_dbg(gtp->dev, "No PDP ctx to decap skb=%p\n", skb); 282 return 1; 283 } 284 285 return gtp_rx(pctx, skb, hdrlen, gtp->role); 286 } 287 288 static void gtp_encap_destroy(struct sock *sk) 289 { 290 struct gtp_dev *gtp; 291 292 gtp = rcu_dereference_sk_user_data(sk); 293 if (gtp) { 294 udp_sk(sk)->encap_type = 0; 295 rcu_assign_sk_user_data(sk, NULL); 296 sock_put(sk); 297 } 298 } 299 300 static void gtp_encap_disable_sock(struct sock *sk) 301 { 302 if (!sk) 303 return; 304 305 gtp_encap_destroy(sk); 306 } 307 308 static void gtp_encap_disable(struct gtp_dev *gtp) 309 { 310 gtp_encap_disable_sock(gtp->sk0); 311 gtp_encap_disable_sock(gtp->sk1u); 312 } 313 314 /* UDP encapsulation receive handler. See net/ipv4/udp.c. 315 * Return codes: 0: success, <0: error, >0: pass up to userspace UDP socket. 316 */ 317 static int gtp_encap_recv(struct sock *sk, struct sk_buff *skb) 318 { 319 struct gtp_dev *gtp; 320 int ret = 0; 321 322 gtp = rcu_dereference_sk_user_data(sk); 323 if (!gtp) 324 return 1; 325 326 netdev_dbg(gtp->dev, "encap_recv sk=%p\n", sk); 327 328 switch (udp_sk(sk)->encap_type) { 329 case UDP_ENCAP_GTP0: 330 netdev_dbg(gtp->dev, "received GTP0 packet\n"); 331 ret = gtp0_udp_encap_recv(gtp, skb); 332 break; 333 case UDP_ENCAP_GTP1U: 334 netdev_dbg(gtp->dev, "received GTP1U packet\n"); 335 ret = gtp1u_udp_encap_recv(gtp, skb); 336 break; 337 default: 338 ret = -1; /* Shouldn't happen. */ 339 } 340 341 switch (ret) { 342 case 1: 343 netdev_dbg(gtp->dev, "pass up to the process\n"); 344 break; 345 case 0: 346 break; 347 case -1: 348 netdev_dbg(gtp->dev, "GTP packet has been dropped\n"); 349 kfree_skb(skb); 350 ret = 0; 351 break; 352 } 353 354 return ret; 355 } 356 357 static int gtp_dev_init(struct net_device *dev) 358 { 359 struct gtp_dev *gtp = netdev_priv(dev); 360 361 gtp->dev = dev; 362 363 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); 364 if (!dev->tstats) 365 return -ENOMEM; 366 367 return 0; 368 } 369 370 static void gtp_dev_uninit(struct net_device *dev) 371 { 372 struct gtp_dev *gtp = netdev_priv(dev); 373 374 gtp_encap_disable(gtp); 375 free_percpu(dev->tstats); 376 } 377 378 static struct rtable *ip4_route_output_gtp(struct flowi4 *fl4, 379 const struct sock *sk, 380 __be32 daddr) 381 { 382 memset(fl4, 0, sizeof(*fl4)); 383 fl4->flowi4_oif = sk->sk_bound_dev_if; 384 fl4->daddr = daddr; 385 fl4->saddr = inet_sk(sk)->inet_saddr; 386 fl4->flowi4_tos = RT_CONN_FLAGS(sk); 387 fl4->flowi4_proto = sk->sk_protocol; 388 389 return ip_route_output_key(sock_net(sk), fl4); 390 } 391 392 static inline void gtp0_push_header(struct sk_buff *skb, struct pdp_ctx *pctx) 393 { 394 int payload_len = skb->len; 395 struct gtp0_header *gtp0; 396 397 gtp0 = skb_push(skb, sizeof(*gtp0)); 398 399 gtp0->flags = 0x1e; /* v0, GTP-non-prime. */ 400 gtp0->type = GTP_TPDU; 401 gtp0->length = htons(payload_len); 402 gtp0->seq = htons((atomic_inc_return(&pctx->tx_seq) - 1) % 0xffff); 403 gtp0->flow = htons(pctx->u.v0.flow); 404 gtp0->number = 0xff; 405 gtp0->spare[0] = gtp0->spare[1] = gtp0->spare[2] = 0xff; 406 gtp0->tid = cpu_to_be64(pctx->u.v0.tid); 407 } 408 409 static inline void gtp1_push_header(struct sk_buff *skb, struct pdp_ctx *pctx) 410 { 411 int payload_len = skb->len; 412 struct gtp1_header *gtp1; 413 414 gtp1 = skb_push(skb, sizeof(*gtp1)); 415 416 /* Bits 8 7 6 5 4 3 2 1 417 * +--+--+--+--+--+--+--+--+ 418 * |version |PT| 0| E| S|PN| 419 * +--+--+--+--+--+--+--+--+ 420 * 0 0 1 1 1 0 0 0 421 */ 422 gtp1->flags = 0x30; /* v1, GTP-non-prime. */ 423 gtp1->type = GTP_TPDU; 424 gtp1->length = htons(payload_len); 425 gtp1->tid = htonl(pctx->u.v1.o_tei); 426 427 /* TODO: Suppport for extension header, sequence number and N-PDU. 428 * Update the length field if any of them is available. 429 */ 430 } 431 432 struct gtp_pktinfo { 433 struct sock *sk; 434 struct iphdr *iph; 435 struct flowi4 fl4; 436 struct rtable *rt; 437 struct pdp_ctx *pctx; 438 struct net_device *dev; 439 __be16 gtph_port; 440 }; 441 442 static void gtp_push_header(struct sk_buff *skb, struct gtp_pktinfo *pktinfo) 443 { 444 switch (pktinfo->pctx->gtp_version) { 445 case GTP_V0: 446 pktinfo->gtph_port = htons(GTP0_PORT); 447 gtp0_push_header(skb, pktinfo->pctx); 448 break; 449 case GTP_V1: 450 pktinfo->gtph_port = htons(GTP1U_PORT); 451 gtp1_push_header(skb, pktinfo->pctx); 452 break; 453 } 454 } 455 456 static inline void gtp_set_pktinfo_ipv4(struct gtp_pktinfo *pktinfo, 457 struct sock *sk, struct iphdr *iph, 458 struct pdp_ctx *pctx, struct rtable *rt, 459 struct flowi4 *fl4, 460 struct net_device *dev) 461 { 462 pktinfo->sk = sk; 463 pktinfo->iph = iph; 464 pktinfo->pctx = pctx; 465 pktinfo->rt = rt; 466 pktinfo->fl4 = *fl4; 467 pktinfo->dev = dev; 468 } 469 470 static int gtp_build_skb_ip4(struct sk_buff *skb, struct net_device *dev, 471 struct gtp_pktinfo *pktinfo) 472 { 473 struct gtp_dev *gtp = netdev_priv(dev); 474 struct pdp_ctx *pctx; 475 struct rtable *rt; 476 struct flowi4 fl4; 477 struct iphdr *iph; 478 __be16 df; 479 int mtu; 480 481 /* Read the IP destination address and resolve the PDP context. 482 * Prepend PDP header with TEI/TID from PDP ctx. 483 */ 484 iph = ip_hdr(skb); 485 if (gtp->role == GTP_ROLE_SGSN) 486 pctx = ipv4_pdp_find(gtp, iph->saddr); 487 else 488 pctx = ipv4_pdp_find(gtp, iph->daddr); 489 490 if (!pctx) { 491 netdev_dbg(dev, "no PDP ctx found for %pI4, skip\n", 492 &iph->daddr); 493 return -ENOENT; 494 } 495 netdev_dbg(dev, "found PDP context %p\n", pctx); 496 497 rt = ip4_route_output_gtp(&fl4, pctx->sk, pctx->peer_addr_ip4.s_addr); 498 if (IS_ERR(rt)) { 499 netdev_dbg(dev, "no route to SSGN %pI4\n", 500 &pctx->peer_addr_ip4.s_addr); 501 dev->stats.tx_carrier_errors++; 502 goto err; 503 } 504 505 if (rt->dst.dev == dev) { 506 netdev_dbg(dev, "circular route to SSGN %pI4\n", 507 &pctx->peer_addr_ip4.s_addr); 508 dev->stats.collisions++; 509 goto err_rt; 510 } 511 512 skb_dst_drop(skb); 513 514 /* This is similar to tnl_update_pmtu(). */ 515 df = iph->frag_off; 516 if (df) { 517 mtu = dst_mtu(&rt->dst) - dev->hard_header_len - 518 sizeof(struct iphdr) - sizeof(struct udphdr); 519 switch (pctx->gtp_version) { 520 case GTP_V0: 521 mtu -= sizeof(struct gtp0_header); 522 break; 523 case GTP_V1: 524 mtu -= sizeof(struct gtp1_header); 525 break; 526 } 527 } else { 528 mtu = dst_mtu(&rt->dst); 529 } 530 531 rt->dst.ops->update_pmtu(&rt->dst, NULL, skb, mtu); 532 533 if (!skb_is_gso(skb) && (iph->frag_off & htons(IP_DF)) && 534 mtu < ntohs(iph->tot_len)) { 535 netdev_dbg(dev, "packet too big, fragmentation needed\n"); 536 memset(IPCB(skb), 0, sizeof(*IPCB(skb))); 537 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, 538 htonl(mtu)); 539 goto err_rt; 540 } 541 542 gtp_set_pktinfo_ipv4(pktinfo, pctx->sk, iph, pctx, rt, &fl4, dev); 543 gtp_push_header(skb, pktinfo); 544 545 return 0; 546 err_rt: 547 ip_rt_put(rt); 548 err: 549 return -EBADMSG; 550 } 551 552 static netdev_tx_t gtp_dev_xmit(struct sk_buff *skb, struct net_device *dev) 553 { 554 unsigned int proto = ntohs(skb->protocol); 555 struct gtp_pktinfo pktinfo; 556 int err; 557 558 /* Ensure there is sufficient headroom. */ 559 if (skb_cow_head(skb, dev->needed_headroom)) 560 goto tx_err; 561 562 skb_reset_inner_headers(skb); 563 564 /* PDP context lookups in gtp_build_skb_*() need rcu read-side lock. */ 565 rcu_read_lock(); 566 switch (proto) { 567 case ETH_P_IP: 568 err = gtp_build_skb_ip4(skb, dev, &pktinfo); 569 break; 570 default: 571 err = -EOPNOTSUPP; 572 break; 573 } 574 rcu_read_unlock(); 575 576 if (err < 0) 577 goto tx_err; 578 579 switch (proto) { 580 case ETH_P_IP: 581 netdev_dbg(pktinfo.dev, "gtp -> IP src: %pI4 dst: %pI4\n", 582 &pktinfo.iph->saddr, &pktinfo.iph->daddr); 583 udp_tunnel_xmit_skb(pktinfo.rt, pktinfo.sk, skb, 584 pktinfo.fl4.saddr, pktinfo.fl4.daddr, 585 pktinfo.iph->tos, 586 ip4_dst_hoplimit(&pktinfo.rt->dst), 587 0, 588 pktinfo.gtph_port, pktinfo.gtph_port, 589 true, false); 590 break; 591 } 592 593 return NETDEV_TX_OK; 594 tx_err: 595 dev->stats.tx_errors++; 596 dev_kfree_skb(skb); 597 return NETDEV_TX_OK; 598 } 599 600 static const struct net_device_ops gtp_netdev_ops = { 601 .ndo_init = gtp_dev_init, 602 .ndo_uninit = gtp_dev_uninit, 603 .ndo_start_xmit = gtp_dev_xmit, 604 .ndo_get_stats64 = ip_tunnel_get_stats64, 605 }; 606 607 static void gtp_link_setup(struct net_device *dev) 608 { 609 dev->netdev_ops = >p_netdev_ops; 610 dev->needs_free_netdev = true; 611 612 dev->hard_header_len = 0; 613 dev->addr_len = 0; 614 615 /* Zero header length. */ 616 dev->type = ARPHRD_NONE; 617 dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST; 618 619 dev->priv_flags |= IFF_NO_QUEUE; 620 dev->features |= NETIF_F_LLTX; 621 netif_keep_dst(dev); 622 623 /* Assume largest header, ie. GTPv0. */ 624 dev->needed_headroom = LL_MAX_HEADER + 625 sizeof(struct iphdr) + 626 sizeof(struct udphdr) + 627 sizeof(struct gtp0_header); 628 } 629 630 static int gtp_hashtable_new(struct gtp_dev *gtp, int hsize); 631 static void gtp_hashtable_free(struct gtp_dev *gtp); 632 static int gtp_encap_enable(struct gtp_dev *gtp, struct nlattr *data[]); 633 634 static int gtp_newlink(struct net *src_net, struct net_device *dev, 635 struct nlattr *tb[], struct nlattr *data[], 636 struct netlink_ext_ack *extack) 637 { 638 struct gtp_dev *gtp; 639 struct gtp_net *gn; 640 int hashsize, err; 641 642 if (!data[IFLA_GTP_FD0] && !data[IFLA_GTP_FD1]) 643 return -EINVAL; 644 645 gtp = netdev_priv(dev); 646 647 err = gtp_encap_enable(gtp, data); 648 if (err < 0) 649 return err; 650 651 if (!data[IFLA_GTP_PDP_HASHSIZE]) 652 hashsize = 1024; 653 else 654 hashsize = nla_get_u32(data[IFLA_GTP_PDP_HASHSIZE]); 655 656 err = gtp_hashtable_new(gtp, hashsize); 657 if (err < 0) 658 goto out_encap; 659 660 err = register_netdevice(dev); 661 if (err < 0) { 662 netdev_dbg(dev, "failed to register new netdev %d\n", err); 663 goto out_hashtable; 664 } 665 666 gn = net_generic(dev_net(dev), gtp_net_id); 667 list_add_rcu(>p->list, &gn->gtp_dev_list); 668 669 netdev_dbg(dev, "registered new GTP interface\n"); 670 671 return 0; 672 673 out_hashtable: 674 gtp_hashtable_free(gtp); 675 out_encap: 676 gtp_encap_disable(gtp); 677 return err; 678 } 679 680 static void gtp_dellink(struct net_device *dev, struct list_head *head) 681 { 682 struct gtp_dev *gtp = netdev_priv(dev); 683 684 gtp_encap_disable(gtp); 685 gtp_hashtable_free(gtp); 686 list_del_rcu(>p->list); 687 unregister_netdevice_queue(dev, head); 688 } 689 690 static const struct nla_policy gtp_policy[IFLA_GTP_MAX + 1] = { 691 [IFLA_GTP_FD0] = { .type = NLA_U32 }, 692 [IFLA_GTP_FD1] = { .type = NLA_U32 }, 693 [IFLA_GTP_PDP_HASHSIZE] = { .type = NLA_U32 }, 694 [IFLA_GTP_ROLE] = { .type = NLA_U32 }, 695 }; 696 697 static int gtp_validate(struct nlattr *tb[], struct nlattr *data[], 698 struct netlink_ext_ack *extack) 699 { 700 if (!data) 701 return -EINVAL; 702 703 return 0; 704 } 705 706 static size_t gtp_get_size(const struct net_device *dev) 707 { 708 return nla_total_size(sizeof(__u32)); /* IFLA_GTP_PDP_HASHSIZE */ 709 } 710 711 static int gtp_fill_info(struct sk_buff *skb, const struct net_device *dev) 712 { 713 struct gtp_dev *gtp = netdev_priv(dev); 714 715 if (nla_put_u32(skb, IFLA_GTP_PDP_HASHSIZE, gtp->hash_size)) 716 goto nla_put_failure; 717 718 return 0; 719 720 nla_put_failure: 721 return -EMSGSIZE; 722 } 723 724 static struct rtnl_link_ops gtp_link_ops __read_mostly = { 725 .kind = "gtp", 726 .maxtype = IFLA_GTP_MAX, 727 .policy = gtp_policy, 728 .priv_size = sizeof(struct gtp_dev), 729 .setup = gtp_link_setup, 730 .validate = gtp_validate, 731 .newlink = gtp_newlink, 732 .dellink = gtp_dellink, 733 .get_size = gtp_get_size, 734 .fill_info = gtp_fill_info, 735 }; 736 737 static int gtp_hashtable_new(struct gtp_dev *gtp, int hsize) 738 { 739 int i; 740 741 gtp->addr_hash = kmalloc_array(hsize, sizeof(struct hlist_head), 742 GFP_KERNEL); 743 if (gtp->addr_hash == NULL) 744 return -ENOMEM; 745 746 gtp->tid_hash = kmalloc_array(hsize, sizeof(struct hlist_head), 747 GFP_KERNEL); 748 if (gtp->tid_hash == NULL) 749 goto err1; 750 751 gtp->hash_size = hsize; 752 753 for (i = 0; i < hsize; i++) { 754 INIT_HLIST_HEAD(>p->addr_hash[i]); 755 INIT_HLIST_HEAD(>p->tid_hash[i]); 756 } 757 return 0; 758 err1: 759 kfree(gtp->addr_hash); 760 return -ENOMEM; 761 } 762 763 static void gtp_hashtable_free(struct gtp_dev *gtp) 764 { 765 struct pdp_ctx *pctx; 766 int i; 767 768 for (i = 0; i < gtp->hash_size; i++) 769 hlist_for_each_entry_rcu(pctx, >p->tid_hash[i], hlist_tid) 770 pdp_context_delete(pctx); 771 772 synchronize_rcu(); 773 kfree(gtp->addr_hash); 774 kfree(gtp->tid_hash); 775 } 776 777 static struct sock *gtp_encap_enable_socket(int fd, int type, 778 struct gtp_dev *gtp) 779 { 780 struct udp_tunnel_sock_cfg tuncfg = {NULL}; 781 struct socket *sock; 782 struct sock *sk; 783 int err; 784 785 pr_debug("enable gtp on %d, %d\n", fd, type); 786 787 sock = sockfd_lookup(fd, &err); 788 if (!sock) { 789 pr_debug("gtp socket fd=%d not found\n", fd); 790 return NULL; 791 } 792 793 if (sock->sk->sk_protocol != IPPROTO_UDP) { 794 pr_debug("socket fd=%d not UDP\n", fd); 795 sk = ERR_PTR(-EINVAL); 796 goto out_sock; 797 } 798 799 if (rcu_dereference_sk_user_data(sock->sk)) { 800 sk = ERR_PTR(-EBUSY); 801 goto out_sock; 802 } 803 804 sk = sock->sk; 805 sock_hold(sk); 806 807 tuncfg.sk_user_data = gtp; 808 tuncfg.encap_type = type; 809 tuncfg.encap_rcv = gtp_encap_recv; 810 tuncfg.encap_destroy = gtp_encap_destroy; 811 812 setup_udp_tunnel_sock(sock_net(sock->sk), sock, &tuncfg); 813 814 out_sock: 815 sockfd_put(sock); 816 return sk; 817 } 818 819 static int gtp_encap_enable(struct gtp_dev *gtp, struct nlattr *data[]) 820 { 821 struct sock *sk1u = NULL; 822 struct sock *sk0 = NULL; 823 unsigned int role = GTP_ROLE_GGSN; 824 825 if (data[IFLA_GTP_FD0]) { 826 u32 fd0 = nla_get_u32(data[IFLA_GTP_FD0]); 827 828 sk0 = gtp_encap_enable_socket(fd0, UDP_ENCAP_GTP0, gtp); 829 if (IS_ERR(sk0)) 830 return PTR_ERR(sk0); 831 } 832 833 if (data[IFLA_GTP_FD1]) { 834 u32 fd1 = nla_get_u32(data[IFLA_GTP_FD1]); 835 836 sk1u = gtp_encap_enable_socket(fd1, UDP_ENCAP_GTP1U, gtp); 837 if (IS_ERR(sk1u)) { 838 if (sk0) 839 gtp_encap_disable_sock(sk0); 840 return PTR_ERR(sk1u); 841 } 842 } 843 844 if (data[IFLA_GTP_ROLE]) { 845 role = nla_get_u32(data[IFLA_GTP_ROLE]); 846 if (role > GTP_ROLE_SGSN) 847 return -EINVAL; 848 } 849 850 gtp->sk0 = sk0; 851 gtp->sk1u = sk1u; 852 gtp->role = role; 853 854 return 0; 855 } 856 857 static struct gtp_dev *gtp_find_dev(struct net *src_net, struct nlattr *nla[]) 858 { 859 struct gtp_dev *gtp = NULL; 860 struct net_device *dev; 861 struct net *net; 862 863 /* Examine the link attributes and figure out which network namespace 864 * we are talking about. 865 */ 866 if (nla[GTPA_NET_NS_FD]) 867 net = get_net_ns_by_fd(nla_get_u32(nla[GTPA_NET_NS_FD])); 868 else 869 net = get_net(src_net); 870 871 if (IS_ERR(net)) 872 return NULL; 873 874 /* Check if there's an existing gtpX device to configure */ 875 dev = dev_get_by_index_rcu(net, nla_get_u32(nla[GTPA_LINK])); 876 if (dev && dev->netdev_ops == >p_netdev_ops) 877 gtp = netdev_priv(dev); 878 879 put_net(net); 880 return gtp; 881 } 882 883 static void ipv4_pdp_fill(struct pdp_ctx *pctx, struct genl_info *info) 884 { 885 pctx->gtp_version = nla_get_u32(info->attrs[GTPA_VERSION]); 886 pctx->af = AF_INET; 887 pctx->peer_addr_ip4.s_addr = 888 nla_get_be32(info->attrs[GTPA_PEER_ADDRESS]); 889 pctx->ms_addr_ip4.s_addr = 890 nla_get_be32(info->attrs[GTPA_MS_ADDRESS]); 891 892 switch (pctx->gtp_version) { 893 case GTP_V0: 894 /* According to TS 09.60, sections 7.5.1 and 7.5.2, the flow 895 * label needs to be the same for uplink and downlink packets, 896 * so let's annotate this. 897 */ 898 pctx->u.v0.tid = nla_get_u64(info->attrs[GTPA_TID]); 899 pctx->u.v0.flow = nla_get_u16(info->attrs[GTPA_FLOW]); 900 break; 901 case GTP_V1: 902 pctx->u.v1.i_tei = nla_get_u32(info->attrs[GTPA_I_TEI]); 903 pctx->u.v1.o_tei = nla_get_u32(info->attrs[GTPA_O_TEI]); 904 break; 905 default: 906 break; 907 } 908 } 909 910 static int ipv4_pdp_add(struct gtp_dev *gtp, struct sock *sk, 911 struct genl_info *info) 912 { 913 struct net_device *dev = gtp->dev; 914 u32 hash_ms, hash_tid = 0; 915 struct pdp_ctx *pctx; 916 bool found = false; 917 __be32 ms_addr; 918 919 ms_addr = nla_get_be32(info->attrs[GTPA_MS_ADDRESS]); 920 hash_ms = ipv4_hashfn(ms_addr) % gtp->hash_size; 921 922 hlist_for_each_entry_rcu(pctx, >p->addr_hash[hash_ms], hlist_addr) { 923 if (pctx->ms_addr_ip4.s_addr == ms_addr) { 924 found = true; 925 break; 926 } 927 } 928 929 if (found) { 930 if (info->nlhdr->nlmsg_flags & NLM_F_EXCL) 931 return -EEXIST; 932 if (info->nlhdr->nlmsg_flags & NLM_F_REPLACE) 933 return -EOPNOTSUPP; 934 935 ipv4_pdp_fill(pctx, info); 936 937 if (pctx->gtp_version == GTP_V0) 938 netdev_dbg(dev, "GTPv0-U: update tunnel id = %llx (pdp %p)\n", 939 pctx->u.v0.tid, pctx); 940 else if (pctx->gtp_version == GTP_V1) 941 netdev_dbg(dev, "GTPv1-U: update tunnel id = %x/%x (pdp %p)\n", 942 pctx->u.v1.i_tei, pctx->u.v1.o_tei, pctx); 943 944 return 0; 945 946 } 947 948 pctx = kmalloc(sizeof(struct pdp_ctx), GFP_KERNEL); 949 if (pctx == NULL) 950 return -ENOMEM; 951 952 sock_hold(sk); 953 pctx->sk = sk; 954 pctx->dev = gtp->dev; 955 ipv4_pdp_fill(pctx, info); 956 atomic_set(&pctx->tx_seq, 0); 957 958 switch (pctx->gtp_version) { 959 case GTP_V0: 960 /* TS 09.60: "The flow label identifies unambiguously a GTP 961 * flow.". We use the tid for this instead, I cannot find a 962 * situation in which this doesn't unambiguosly identify the 963 * PDP context. 964 */ 965 hash_tid = gtp0_hashfn(pctx->u.v0.tid) % gtp->hash_size; 966 break; 967 case GTP_V1: 968 hash_tid = gtp1u_hashfn(pctx->u.v1.i_tei) % gtp->hash_size; 969 break; 970 } 971 972 hlist_add_head_rcu(&pctx->hlist_addr, >p->addr_hash[hash_ms]); 973 hlist_add_head_rcu(&pctx->hlist_tid, >p->tid_hash[hash_tid]); 974 975 switch (pctx->gtp_version) { 976 case GTP_V0: 977 netdev_dbg(dev, "GTPv0-U: new PDP ctx id=%llx ssgn=%pI4 ms=%pI4 (pdp=%p)\n", 978 pctx->u.v0.tid, &pctx->peer_addr_ip4, 979 &pctx->ms_addr_ip4, pctx); 980 break; 981 case GTP_V1: 982 netdev_dbg(dev, "GTPv1-U: new PDP ctx id=%x/%x ssgn=%pI4 ms=%pI4 (pdp=%p)\n", 983 pctx->u.v1.i_tei, pctx->u.v1.o_tei, 984 &pctx->peer_addr_ip4, &pctx->ms_addr_ip4, pctx); 985 break; 986 } 987 988 return 0; 989 } 990 991 static void pdp_context_free(struct rcu_head *head) 992 { 993 struct pdp_ctx *pctx = container_of(head, struct pdp_ctx, rcu_head); 994 995 sock_put(pctx->sk); 996 kfree(pctx); 997 } 998 999 static void pdp_context_delete(struct pdp_ctx *pctx) 1000 { 1001 hlist_del_rcu(&pctx->hlist_tid); 1002 hlist_del_rcu(&pctx->hlist_addr); 1003 call_rcu(&pctx->rcu_head, pdp_context_free); 1004 } 1005 1006 static int gtp_genl_new_pdp(struct sk_buff *skb, struct genl_info *info) 1007 { 1008 unsigned int version; 1009 struct gtp_dev *gtp; 1010 struct sock *sk; 1011 int err; 1012 1013 if (!info->attrs[GTPA_VERSION] || 1014 !info->attrs[GTPA_LINK] || 1015 !info->attrs[GTPA_PEER_ADDRESS] || 1016 !info->attrs[GTPA_MS_ADDRESS]) 1017 return -EINVAL; 1018 1019 version = nla_get_u32(info->attrs[GTPA_VERSION]); 1020 1021 switch (version) { 1022 case GTP_V0: 1023 if (!info->attrs[GTPA_TID] || 1024 !info->attrs[GTPA_FLOW]) 1025 return -EINVAL; 1026 break; 1027 case GTP_V1: 1028 if (!info->attrs[GTPA_I_TEI] || 1029 !info->attrs[GTPA_O_TEI]) 1030 return -EINVAL; 1031 break; 1032 1033 default: 1034 return -EINVAL; 1035 } 1036 1037 rcu_read_lock(); 1038 1039 gtp = gtp_find_dev(sock_net(skb->sk), info->attrs); 1040 if (!gtp) { 1041 err = -ENODEV; 1042 goto out_unlock; 1043 } 1044 1045 if (version == GTP_V0) 1046 sk = gtp->sk0; 1047 else if (version == GTP_V1) 1048 sk = gtp->sk1u; 1049 else 1050 sk = NULL; 1051 1052 if (!sk) { 1053 err = -ENODEV; 1054 goto out_unlock; 1055 } 1056 1057 err = ipv4_pdp_add(gtp, sk, info); 1058 1059 out_unlock: 1060 rcu_read_unlock(); 1061 return err; 1062 } 1063 1064 static struct pdp_ctx *gtp_find_pdp_by_link(struct net *net, 1065 struct nlattr *nla[]) 1066 { 1067 struct gtp_dev *gtp; 1068 1069 gtp = gtp_find_dev(net, nla); 1070 if (!gtp) 1071 return ERR_PTR(-ENODEV); 1072 1073 if (nla[GTPA_MS_ADDRESS]) { 1074 __be32 ip = nla_get_be32(nla[GTPA_MS_ADDRESS]); 1075 1076 return ipv4_pdp_find(gtp, ip); 1077 } else if (nla[GTPA_VERSION]) { 1078 u32 gtp_version = nla_get_u32(nla[GTPA_VERSION]); 1079 1080 if (gtp_version == GTP_V0 && nla[GTPA_TID]) 1081 return gtp0_pdp_find(gtp, nla_get_u64(nla[GTPA_TID])); 1082 else if (gtp_version == GTP_V1 && nla[GTPA_I_TEI]) 1083 return gtp1_pdp_find(gtp, nla_get_u32(nla[GTPA_I_TEI])); 1084 } 1085 1086 return ERR_PTR(-EINVAL); 1087 } 1088 1089 static struct pdp_ctx *gtp_find_pdp(struct net *net, struct nlattr *nla[]) 1090 { 1091 struct pdp_ctx *pctx; 1092 1093 if (nla[GTPA_LINK]) 1094 pctx = gtp_find_pdp_by_link(net, nla); 1095 else 1096 pctx = ERR_PTR(-EINVAL); 1097 1098 if (!pctx) 1099 pctx = ERR_PTR(-ENOENT); 1100 1101 return pctx; 1102 } 1103 1104 static int gtp_genl_del_pdp(struct sk_buff *skb, struct genl_info *info) 1105 { 1106 struct pdp_ctx *pctx; 1107 int err = 0; 1108 1109 if (!info->attrs[GTPA_VERSION]) 1110 return -EINVAL; 1111 1112 rcu_read_lock(); 1113 1114 pctx = gtp_find_pdp(sock_net(skb->sk), info->attrs); 1115 if (IS_ERR(pctx)) { 1116 err = PTR_ERR(pctx); 1117 goto out_unlock; 1118 } 1119 1120 if (pctx->gtp_version == GTP_V0) 1121 netdev_dbg(pctx->dev, "GTPv0-U: deleting tunnel id = %llx (pdp %p)\n", 1122 pctx->u.v0.tid, pctx); 1123 else if (pctx->gtp_version == GTP_V1) 1124 netdev_dbg(pctx->dev, "GTPv1-U: deleting tunnel id = %x/%x (pdp %p)\n", 1125 pctx->u.v1.i_tei, pctx->u.v1.o_tei, pctx); 1126 1127 pdp_context_delete(pctx); 1128 1129 out_unlock: 1130 rcu_read_unlock(); 1131 return err; 1132 } 1133 1134 static struct genl_family gtp_genl_family; 1135 1136 static int gtp_genl_fill_info(struct sk_buff *skb, u32 snd_portid, u32 snd_seq, 1137 u32 type, struct pdp_ctx *pctx) 1138 { 1139 void *genlh; 1140 1141 genlh = genlmsg_put(skb, snd_portid, snd_seq, >p_genl_family, 0, 1142 type); 1143 if (genlh == NULL) 1144 goto nlmsg_failure; 1145 1146 if (nla_put_u32(skb, GTPA_VERSION, pctx->gtp_version) || 1147 nla_put_be32(skb, GTPA_PEER_ADDRESS, pctx->peer_addr_ip4.s_addr) || 1148 nla_put_be32(skb, GTPA_MS_ADDRESS, pctx->ms_addr_ip4.s_addr)) 1149 goto nla_put_failure; 1150 1151 switch (pctx->gtp_version) { 1152 case GTP_V0: 1153 if (nla_put_u64_64bit(skb, GTPA_TID, pctx->u.v0.tid, GTPA_PAD) || 1154 nla_put_u16(skb, GTPA_FLOW, pctx->u.v0.flow)) 1155 goto nla_put_failure; 1156 break; 1157 case GTP_V1: 1158 if (nla_put_u32(skb, GTPA_I_TEI, pctx->u.v1.i_tei) || 1159 nla_put_u32(skb, GTPA_O_TEI, pctx->u.v1.o_tei)) 1160 goto nla_put_failure; 1161 break; 1162 } 1163 genlmsg_end(skb, genlh); 1164 return 0; 1165 1166 nlmsg_failure: 1167 nla_put_failure: 1168 genlmsg_cancel(skb, genlh); 1169 return -EMSGSIZE; 1170 } 1171 1172 static int gtp_genl_get_pdp(struct sk_buff *skb, struct genl_info *info) 1173 { 1174 struct pdp_ctx *pctx = NULL; 1175 struct sk_buff *skb2; 1176 int err; 1177 1178 if (!info->attrs[GTPA_VERSION]) 1179 return -EINVAL; 1180 1181 rcu_read_lock(); 1182 1183 pctx = gtp_find_pdp(sock_net(skb->sk), info->attrs); 1184 if (IS_ERR(pctx)) { 1185 err = PTR_ERR(pctx); 1186 goto err_unlock; 1187 } 1188 1189 skb2 = genlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC); 1190 if (skb2 == NULL) { 1191 err = -ENOMEM; 1192 goto err_unlock; 1193 } 1194 1195 err = gtp_genl_fill_info(skb2, NETLINK_CB(skb).portid, 1196 info->snd_seq, info->nlhdr->nlmsg_type, pctx); 1197 if (err < 0) 1198 goto err_unlock_free; 1199 1200 rcu_read_unlock(); 1201 return genlmsg_unicast(genl_info_net(info), skb2, info->snd_portid); 1202 1203 err_unlock_free: 1204 kfree_skb(skb2); 1205 err_unlock: 1206 rcu_read_unlock(); 1207 return err; 1208 } 1209 1210 static int gtp_genl_dump_pdp(struct sk_buff *skb, 1211 struct netlink_callback *cb) 1212 { 1213 struct gtp_dev *last_gtp = (struct gtp_dev *)cb->args[2], *gtp; 1214 struct net *net = sock_net(skb->sk); 1215 struct gtp_net *gn = net_generic(net, gtp_net_id); 1216 unsigned long tid = cb->args[1]; 1217 int i, k = cb->args[0], ret; 1218 struct pdp_ctx *pctx; 1219 1220 if (cb->args[4]) 1221 return 0; 1222 1223 list_for_each_entry_rcu(gtp, &gn->gtp_dev_list, list) { 1224 if (last_gtp && last_gtp != gtp) 1225 continue; 1226 else 1227 last_gtp = NULL; 1228 1229 for (i = k; i < gtp->hash_size; i++) { 1230 hlist_for_each_entry_rcu(pctx, >p->tid_hash[i], hlist_tid) { 1231 if (tid && tid != pctx->u.tid) 1232 continue; 1233 else 1234 tid = 0; 1235 1236 ret = gtp_genl_fill_info(skb, 1237 NETLINK_CB(cb->skb).portid, 1238 cb->nlh->nlmsg_seq, 1239 cb->nlh->nlmsg_type, pctx); 1240 if (ret < 0) { 1241 cb->args[0] = i; 1242 cb->args[1] = pctx->u.tid; 1243 cb->args[2] = (unsigned long)gtp; 1244 goto out; 1245 } 1246 } 1247 } 1248 } 1249 cb->args[4] = 1; 1250 out: 1251 return skb->len; 1252 } 1253 1254 static const struct nla_policy gtp_genl_policy[GTPA_MAX + 1] = { 1255 [GTPA_LINK] = { .type = NLA_U32, }, 1256 [GTPA_VERSION] = { .type = NLA_U32, }, 1257 [GTPA_TID] = { .type = NLA_U64, }, 1258 [GTPA_PEER_ADDRESS] = { .type = NLA_U32, }, 1259 [GTPA_MS_ADDRESS] = { .type = NLA_U32, }, 1260 [GTPA_FLOW] = { .type = NLA_U16, }, 1261 [GTPA_NET_NS_FD] = { .type = NLA_U32, }, 1262 [GTPA_I_TEI] = { .type = NLA_U32, }, 1263 [GTPA_O_TEI] = { .type = NLA_U32, }, 1264 }; 1265 1266 static const struct genl_ops gtp_genl_ops[] = { 1267 { 1268 .cmd = GTP_CMD_NEWPDP, 1269 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, 1270 .doit = gtp_genl_new_pdp, 1271 .flags = GENL_ADMIN_PERM, 1272 }, 1273 { 1274 .cmd = GTP_CMD_DELPDP, 1275 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, 1276 .doit = gtp_genl_del_pdp, 1277 .flags = GENL_ADMIN_PERM, 1278 }, 1279 { 1280 .cmd = GTP_CMD_GETPDP, 1281 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, 1282 .doit = gtp_genl_get_pdp, 1283 .dumpit = gtp_genl_dump_pdp, 1284 .flags = GENL_ADMIN_PERM, 1285 }, 1286 }; 1287 1288 static struct genl_family gtp_genl_family __ro_after_init = { 1289 .name = "gtp", 1290 .version = 0, 1291 .hdrsize = 0, 1292 .maxattr = GTPA_MAX, 1293 .policy = gtp_genl_policy, 1294 .netnsok = true, 1295 .module = THIS_MODULE, 1296 .ops = gtp_genl_ops, 1297 .n_ops = ARRAY_SIZE(gtp_genl_ops), 1298 }; 1299 1300 static int __net_init gtp_net_init(struct net *net) 1301 { 1302 struct gtp_net *gn = net_generic(net, gtp_net_id); 1303 1304 INIT_LIST_HEAD(&gn->gtp_dev_list); 1305 return 0; 1306 } 1307 1308 static void __net_exit gtp_net_exit(struct net *net) 1309 { 1310 struct gtp_net *gn = net_generic(net, gtp_net_id); 1311 struct gtp_dev *gtp; 1312 LIST_HEAD(list); 1313 1314 rtnl_lock(); 1315 list_for_each_entry(gtp, &gn->gtp_dev_list, list) 1316 gtp_dellink(gtp->dev, &list); 1317 1318 unregister_netdevice_many(&list); 1319 rtnl_unlock(); 1320 } 1321 1322 static struct pernet_operations gtp_net_ops = { 1323 .init = gtp_net_init, 1324 .exit = gtp_net_exit, 1325 .id = >p_net_id, 1326 .size = sizeof(struct gtp_net), 1327 }; 1328 1329 static int __init gtp_init(void) 1330 { 1331 int err; 1332 1333 get_random_bytes(>p_h_initval, sizeof(gtp_h_initval)); 1334 1335 err = rtnl_link_register(>p_link_ops); 1336 if (err < 0) 1337 goto error_out; 1338 1339 err = genl_register_family(>p_genl_family); 1340 if (err < 0) 1341 goto unreg_rtnl_link; 1342 1343 err = register_pernet_subsys(>p_net_ops); 1344 if (err < 0) 1345 goto unreg_genl_family; 1346 1347 pr_info("GTP module loaded (pdp ctx size %zd bytes)\n", 1348 sizeof(struct pdp_ctx)); 1349 return 0; 1350 1351 unreg_genl_family: 1352 genl_unregister_family(>p_genl_family); 1353 unreg_rtnl_link: 1354 rtnl_link_unregister(>p_link_ops); 1355 error_out: 1356 pr_err("error loading GTP module loaded\n"); 1357 return err; 1358 } 1359 late_initcall(gtp_init); 1360 1361 static void __exit gtp_fini(void) 1362 { 1363 unregister_pernet_subsys(>p_net_ops); 1364 genl_unregister_family(>p_genl_family); 1365 rtnl_link_unregister(>p_link_ops); 1366 1367 pr_info("GTP module unloaded\n"); 1368 } 1369 module_exit(gtp_fini); 1370 1371 MODULE_LICENSE("GPL"); 1372 MODULE_AUTHOR("Harald Welte <hwelte@sysmocom.de>"); 1373 MODULE_DESCRIPTION("Interface driver for GTP encapsulated traffic"); 1374 MODULE_ALIAS_RTNL_LINK("gtp"); 1375 MODULE_ALIAS_GENL_FAMILY("gtp"); 1376