Pablo Neira | 459aa66 | 2016-05-09 00:55:48 +0200 | [diff] [blame] | 1 | /* GTP according to GSM TS 09.60 / 3GPP TS 29.060 |
| 2 | * |
| 3 | * (C) 2012-2014 by sysmocom - s.f.m.c. GmbH |
| 4 | * (C) 2016 by Pablo Neira Ayuso <pablo@netfilter.org> |
| 5 | * |
| 6 | * Author: Harald Welte <hwelte@sysmocom.de> |
| 7 | * Pablo Neira Ayuso <pablo@netfilter.org> |
| 8 | * Andreas Schultz <aschultz@travelping.com> |
| 9 | * |
| 10 | * This program is free software; you can redistribute it and/or |
| 11 | * modify it under the terms of the GNU General Public License |
| 12 | * as published by the Free Software Foundation; either version |
| 13 | * 2 of the License, or (at your option) any later version. |
| 14 | */ |
| 15 | |
| 16 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| 17 | |
| 18 | #include <linux/module.h> |
Pablo Neira | 459aa66 | 2016-05-09 00:55:48 +0200 | [diff] [blame] | 19 | #include <linux/skbuff.h> |
| 20 | #include <linux/udp.h> |
| 21 | #include <linux/rculist.h> |
| 22 | #include <linux/jhash.h> |
| 23 | #include <linux/if_tunnel.h> |
| 24 | #include <linux/net.h> |
| 25 | #include <linux/file.h> |
| 26 | #include <linux/gtp.h> |
| 27 | |
| 28 | #include <net/net_namespace.h> |
| 29 | #include <net/protocol.h> |
| 30 | #include <net/ip.h> |
| 31 | #include <net/udp.h> |
| 32 | #include <net/udp_tunnel.h> |
| 33 | #include <net/icmp.h> |
| 34 | #include <net/xfrm.h> |
| 35 | #include <net/genetlink.h> |
| 36 | #include <net/netns/generic.h> |
| 37 | #include <net/gtp.h> |
| 38 | |
| 39 | /* An active session for the subscriber. */ |
| 40 | struct pdp_ctx { |
| 41 | struct hlist_node hlist_tid; |
| 42 | struct hlist_node hlist_addr; |
| 43 | |
| 44 | union { |
| 45 | u64 tid; |
| 46 | struct { |
| 47 | u64 tid; |
| 48 | u16 flow; |
| 49 | } v0; |
| 50 | struct { |
| 51 | u32 i_tei; |
| 52 | u32 o_tei; |
| 53 | } v1; |
| 54 | } u; |
| 55 | u8 gtp_version; |
| 56 | u16 af; |
| 57 | |
| 58 | struct in_addr ms_addr_ip4; |
| 59 | struct in_addr sgsn_addr_ip4; |
| 60 | |
| 61 | atomic_t tx_seq; |
| 62 | struct rcu_head rcu_head; |
| 63 | }; |
| 64 | |
| 65 | /* One instance of the GTP device. */ |
| 66 | struct gtp_dev { |
| 67 | struct list_head list; |
| 68 | |
| 69 | struct socket *sock0; |
| 70 | struct socket *sock1u; |
| 71 | |
| 72 | struct net *net; |
| 73 | struct net_device *dev; |
| 74 | |
| 75 | unsigned int hash_size; |
| 76 | struct hlist_head *tid_hash; |
| 77 | struct hlist_head *addr_hash; |
| 78 | }; |
| 79 | |
| 80 | static int gtp_net_id __read_mostly; |
| 81 | |
| 82 | struct gtp_net { |
| 83 | struct list_head gtp_dev_list; |
| 84 | }; |
| 85 | |
| 86 | static u32 gtp_h_initval; |
| 87 | |
| 88 | static inline u32 gtp0_hashfn(u64 tid) |
| 89 | { |
| 90 | u32 *tid32 = (u32 *) &tid; |
| 91 | return jhash_2words(tid32[0], tid32[1], gtp_h_initval); |
| 92 | } |
| 93 | |
| 94 | static inline u32 gtp1u_hashfn(u32 tid) |
| 95 | { |
| 96 | return jhash_1word(tid, gtp_h_initval); |
| 97 | } |
| 98 | |
| 99 | static inline u32 ipv4_hashfn(__be32 ip) |
| 100 | { |
| 101 | return jhash_1word((__force u32)ip, gtp_h_initval); |
| 102 | } |
| 103 | |
| 104 | /* Resolve a PDP context structure based on the 64bit TID. */ |
| 105 | static struct pdp_ctx *gtp0_pdp_find(struct gtp_dev *gtp, u64 tid) |
| 106 | { |
| 107 | struct hlist_head *head; |
| 108 | struct pdp_ctx *pdp; |
| 109 | |
| 110 | head = >p->tid_hash[gtp0_hashfn(tid) % gtp->hash_size]; |
| 111 | |
| 112 | hlist_for_each_entry_rcu(pdp, head, hlist_tid) { |
| 113 | if (pdp->gtp_version == GTP_V0 && |
| 114 | pdp->u.v0.tid == tid) |
| 115 | return pdp; |
| 116 | } |
| 117 | return NULL; |
| 118 | } |
| 119 | |
| 120 | /* Resolve a PDP context structure based on the 32bit TEI. */ |
| 121 | static struct pdp_ctx *gtp1_pdp_find(struct gtp_dev *gtp, u32 tid) |
| 122 | { |
| 123 | struct hlist_head *head; |
| 124 | struct pdp_ctx *pdp; |
| 125 | |
| 126 | head = >p->tid_hash[gtp1u_hashfn(tid) % gtp->hash_size]; |
| 127 | |
| 128 | hlist_for_each_entry_rcu(pdp, head, hlist_tid) { |
| 129 | if (pdp->gtp_version == GTP_V1 && |
| 130 | pdp->u.v1.i_tei == tid) |
| 131 | return pdp; |
| 132 | } |
| 133 | return NULL; |
| 134 | } |
| 135 | |
| 136 | /* Resolve a PDP context based on IPv4 address of MS. */ |
| 137 | static struct pdp_ctx *ipv4_pdp_find(struct gtp_dev *gtp, __be32 ms_addr) |
| 138 | { |
| 139 | struct hlist_head *head; |
| 140 | struct pdp_ctx *pdp; |
| 141 | |
| 142 | head = >p->addr_hash[ipv4_hashfn(ms_addr) % gtp->hash_size]; |
| 143 | |
| 144 | hlist_for_each_entry_rcu(pdp, head, hlist_addr) { |
| 145 | if (pdp->af == AF_INET && |
| 146 | pdp->ms_addr_ip4.s_addr == ms_addr) |
| 147 | return pdp; |
| 148 | } |
| 149 | |
| 150 | return NULL; |
| 151 | } |
| 152 | |
| 153 | static bool gtp_check_src_ms_ipv4(struct sk_buff *skb, struct pdp_ctx *pctx, |
| 154 | unsigned int hdrlen) |
| 155 | { |
| 156 | struct iphdr *iph; |
| 157 | |
| 158 | if (!pskb_may_pull(skb, hdrlen + sizeof(struct iphdr))) |
| 159 | return false; |
| 160 | |
| 161 | iph = (struct iphdr *)(skb->data + hdrlen + sizeof(struct iphdr)); |
| 162 | |
| 163 | return iph->saddr != pctx->ms_addr_ip4.s_addr; |
| 164 | } |
| 165 | |
| 166 | /* Check if the inner IP source address in this packet is assigned to any |
| 167 | * existing mobile subscriber. |
| 168 | */ |
| 169 | static bool gtp_check_src_ms(struct sk_buff *skb, struct pdp_ctx *pctx, |
| 170 | unsigned int hdrlen) |
| 171 | { |
| 172 | switch (ntohs(skb->protocol)) { |
| 173 | case ETH_P_IP: |
| 174 | return gtp_check_src_ms_ipv4(skb, pctx, hdrlen); |
| 175 | } |
| 176 | return false; |
| 177 | } |
| 178 | |
| 179 | /* 1 means pass up to the stack, -1 means drop and 0 means decapsulated. */ |
| 180 | static int gtp0_udp_encap_recv(struct gtp_dev *gtp, struct sk_buff *skb, |
| 181 | bool xnet) |
| 182 | { |
| 183 | unsigned int hdrlen = sizeof(struct udphdr) + |
| 184 | sizeof(struct gtp0_header); |
| 185 | struct gtp0_header *gtp0; |
| 186 | struct pdp_ctx *pctx; |
| 187 | int ret = 0; |
| 188 | |
| 189 | if (!pskb_may_pull(skb, hdrlen)) |
| 190 | return -1; |
| 191 | |
| 192 | gtp0 = (struct gtp0_header *)(skb->data + sizeof(struct udphdr)); |
| 193 | |
| 194 | if ((gtp0->flags >> 5) != GTP_V0) |
| 195 | return 1; |
| 196 | |
| 197 | if (gtp0->type != GTP_TPDU) |
| 198 | return 1; |
| 199 | |
| 200 | rcu_read_lock(); |
| 201 | pctx = gtp0_pdp_find(gtp, be64_to_cpu(gtp0->tid)); |
| 202 | if (!pctx) { |
| 203 | netdev_dbg(gtp->dev, "No PDP ctx to decap skb=%p\n", skb); |
| 204 | ret = -1; |
| 205 | goto out_rcu; |
| 206 | } |
| 207 | |
| 208 | if (!gtp_check_src_ms(skb, pctx, hdrlen)) { |
| 209 | netdev_dbg(gtp->dev, "No PDP ctx for this MS\n"); |
| 210 | ret = -1; |
| 211 | goto out_rcu; |
| 212 | } |
| 213 | rcu_read_unlock(); |
| 214 | |
| 215 | /* Get rid of the GTP + UDP headers. */ |
| 216 | return iptunnel_pull_header(skb, hdrlen, skb->protocol, xnet); |
| 217 | out_rcu: |
| 218 | rcu_read_unlock(); |
| 219 | return ret; |
| 220 | } |
| 221 | |
| 222 | static int gtp1u_udp_encap_recv(struct gtp_dev *gtp, struct sk_buff *skb, |
| 223 | bool xnet) |
| 224 | { |
| 225 | unsigned int hdrlen = sizeof(struct udphdr) + |
| 226 | sizeof(struct gtp1_header); |
| 227 | struct gtp1_header *gtp1; |
| 228 | struct pdp_ctx *pctx; |
| 229 | int ret = 0; |
| 230 | |
| 231 | if (!pskb_may_pull(skb, hdrlen)) |
| 232 | return -1; |
| 233 | |
| 234 | gtp1 = (struct gtp1_header *)(skb->data + sizeof(struct udphdr)); |
| 235 | |
| 236 | if ((gtp1->flags >> 5) != GTP_V1) |
| 237 | return 1; |
| 238 | |
| 239 | if (gtp1->type != GTP_TPDU) |
| 240 | return 1; |
| 241 | |
| 242 | /* From 29.060: "This field shall be present if and only if any one or |
| 243 | * more of the S, PN and E flags are set.". |
| 244 | * |
| 245 | * If any of the bit is set, then the remaining ones also have to be |
| 246 | * set. |
| 247 | */ |
| 248 | if (gtp1->flags & GTP1_F_MASK) |
| 249 | hdrlen += 4; |
| 250 | |
| 251 | /* Make sure the header is larger enough, including extensions. */ |
| 252 | if (!pskb_may_pull(skb, hdrlen)) |
| 253 | return -1; |
| 254 | |
Pablo Neira | 93edb8c | 2016-05-10 21:33:38 +0200 | [diff] [blame] | 255 | gtp1 = (struct gtp1_header *)(skb->data + sizeof(struct udphdr)); |
| 256 | |
Pablo Neira | 459aa66 | 2016-05-09 00:55:48 +0200 | [diff] [blame] | 257 | rcu_read_lock(); |
| 258 | pctx = gtp1_pdp_find(gtp, ntohl(gtp1->tid)); |
| 259 | if (!pctx) { |
| 260 | netdev_dbg(gtp->dev, "No PDP ctx to decap skb=%p\n", skb); |
| 261 | ret = -1; |
| 262 | goto out_rcu; |
| 263 | } |
| 264 | |
| 265 | if (!gtp_check_src_ms(skb, pctx, hdrlen)) { |
| 266 | netdev_dbg(gtp->dev, "No PDP ctx for this MS\n"); |
| 267 | ret = -1; |
| 268 | goto out_rcu; |
| 269 | } |
| 270 | rcu_read_unlock(); |
| 271 | |
| 272 | /* Get rid of the GTP + UDP headers. */ |
| 273 | return iptunnel_pull_header(skb, hdrlen, skb->protocol, xnet); |
| 274 | out_rcu: |
| 275 | rcu_read_unlock(); |
| 276 | return ret; |
| 277 | } |
| 278 | |
| 279 | static void gtp_encap_disable(struct gtp_dev *gtp) |
| 280 | { |
| 281 | if (gtp->sock0 && gtp->sock0->sk) { |
| 282 | udp_sk(gtp->sock0->sk)->encap_type = 0; |
| 283 | rcu_assign_sk_user_data(gtp->sock0->sk, NULL); |
| 284 | } |
| 285 | if (gtp->sock1u && gtp->sock1u->sk) { |
| 286 | udp_sk(gtp->sock1u->sk)->encap_type = 0; |
| 287 | rcu_assign_sk_user_data(gtp->sock1u->sk, NULL); |
| 288 | } |
| 289 | |
| 290 | gtp->sock0 = NULL; |
| 291 | gtp->sock1u = NULL; |
| 292 | } |
| 293 | |
| 294 | static void gtp_encap_destroy(struct sock *sk) |
| 295 | { |
| 296 | struct gtp_dev *gtp; |
| 297 | |
| 298 | gtp = rcu_dereference_sk_user_data(sk); |
| 299 | if (gtp) |
| 300 | gtp_encap_disable(gtp); |
| 301 | } |
| 302 | |
| 303 | /* UDP encapsulation receive handler. See net/ipv4/udp.c. |
| 304 | * Return codes: 0: success, <0: error, >0: pass up to userspace UDP socket. |
| 305 | */ |
| 306 | static int gtp_encap_recv(struct sock *sk, struct sk_buff *skb) |
| 307 | { |
| 308 | struct pcpu_sw_netstats *stats; |
| 309 | struct gtp_dev *gtp; |
| 310 | bool xnet; |
| 311 | int ret; |
| 312 | |
| 313 | gtp = rcu_dereference_sk_user_data(sk); |
| 314 | if (!gtp) |
| 315 | return 1; |
| 316 | |
| 317 | netdev_dbg(gtp->dev, "encap_recv sk=%p\n", sk); |
| 318 | |
| 319 | xnet = !net_eq(gtp->net, dev_net(gtp->dev)); |
| 320 | |
| 321 | switch (udp_sk(sk)->encap_type) { |
| 322 | case UDP_ENCAP_GTP0: |
| 323 | netdev_dbg(gtp->dev, "received GTP0 packet\n"); |
| 324 | ret = gtp0_udp_encap_recv(gtp, skb, xnet); |
| 325 | break; |
| 326 | case UDP_ENCAP_GTP1U: |
| 327 | netdev_dbg(gtp->dev, "received GTP1U packet\n"); |
| 328 | ret = gtp1u_udp_encap_recv(gtp, skb, xnet); |
| 329 | break; |
| 330 | default: |
| 331 | ret = -1; /* Shouldn't happen. */ |
| 332 | } |
| 333 | |
| 334 | switch (ret) { |
| 335 | case 1: |
| 336 | netdev_dbg(gtp->dev, "pass up to the process\n"); |
| 337 | return 1; |
| 338 | case 0: |
| 339 | netdev_dbg(gtp->dev, "forwarding packet from GGSN to uplink\n"); |
| 340 | break; |
| 341 | case -1: |
| 342 | netdev_dbg(gtp->dev, "GTP packet has been dropped\n"); |
| 343 | kfree_skb(skb); |
| 344 | return 0; |
| 345 | } |
| 346 | |
| 347 | /* Now that the UDP and the GTP header have been removed, set up the |
| 348 | * new network header. This is required by the upper layer to |
| 349 | * calculate the transport header. |
| 350 | */ |
| 351 | skb_reset_network_header(skb); |
| 352 | |
| 353 | skb->dev = gtp->dev; |
| 354 | |
| 355 | stats = this_cpu_ptr(gtp->dev->tstats); |
| 356 | u64_stats_update_begin(&stats->syncp); |
| 357 | stats->rx_packets++; |
| 358 | stats->rx_bytes += skb->len; |
| 359 | u64_stats_update_end(&stats->syncp); |
| 360 | |
| 361 | netif_rx(skb); |
| 362 | |
| 363 | return 0; |
| 364 | } |
| 365 | |
| 366 | static int gtp_dev_init(struct net_device *dev) |
| 367 | { |
| 368 | struct gtp_dev *gtp = netdev_priv(dev); |
| 369 | |
| 370 | gtp->dev = dev; |
| 371 | |
| 372 | dev->tstats = alloc_percpu(struct pcpu_sw_netstats); |
| 373 | if (!dev->tstats) |
| 374 | return -ENOMEM; |
| 375 | |
| 376 | return 0; |
| 377 | } |
| 378 | |
| 379 | static void gtp_dev_uninit(struct net_device *dev) |
| 380 | { |
| 381 | struct gtp_dev *gtp = netdev_priv(dev); |
| 382 | |
| 383 | gtp_encap_disable(gtp); |
| 384 | free_percpu(dev->tstats); |
| 385 | } |
| 386 | |
| 387 | static struct rtable *ip4_route_output_gtp(struct net *net, struct flowi4 *fl4, |
| 388 | const struct sock *sk, __be32 daddr) |
| 389 | { |
| 390 | memset(fl4, 0, sizeof(*fl4)); |
| 391 | fl4->flowi4_oif = sk->sk_bound_dev_if; |
| 392 | fl4->daddr = daddr; |
| 393 | fl4->saddr = inet_sk(sk)->inet_saddr; |
| 394 | fl4->flowi4_tos = RT_CONN_FLAGS(sk); |
| 395 | fl4->flowi4_proto = sk->sk_protocol; |
| 396 | |
| 397 | return ip_route_output_key(net, fl4); |
| 398 | } |
| 399 | |
| 400 | static inline void gtp0_push_header(struct sk_buff *skb, struct pdp_ctx *pctx) |
| 401 | { |
| 402 | int payload_len = skb->len; |
| 403 | struct gtp0_header *gtp0; |
| 404 | |
| 405 | gtp0 = (struct gtp0_header *) skb_push(skb, sizeof(*gtp0)); |
| 406 | |
| 407 | gtp0->flags = 0x1e; /* v0, GTP-non-prime. */ |
| 408 | gtp0->type = GTP_TPDU; |
| 409 | gtp0->length = htons(payload_len); |
| 410 | gtp0->seq = htons((atomic_inc_return(&pctx->tx_seq) - 1) % 0xffff); |
| 411 | gtp0->flow = htons(pctx->u.v0.flow); |
| 412 | gtp0->number = 0xff; |
| 413 | gtp0->spare[0] = gtp0->spare[1] = gtp0->spare[2] = 0xff; |
| 414 | gtp0->tid = cpu_to_be64(pctx->u.v0.tid); |
| 415 | } |
| 416 | |
| 417 | static inline void gtp1_push_header(struct sk_buff *skb, struct pdp_ctx *pctx) |
| 418 | { |
| 419 | int payload_len = skb->len; |
| 420 | struct gtp1_header *gtp1; |
| 421 | |
| 422 | gtp1 = (struct gtp1_header *) skb_push(skb, sizeof(*gtp1)); |
| 423 | |
| 424 | /* Bits 8 7 6 5 4 3 2 1 |
| 425 | * +--+--+--+--+--+--+--+--+ |
| 426 | * |version |PT| 1| E| S|PN| |
| 427 | * +--+--+--+--+--+--+--+--+ |
| 428 | * 0 0 1 1 1 0 0 0 |
| 429 | */ |
| 430 | gtp1->flags = 0x38; /* v1, GTP-non-prime. */ |
| 431 | gtp1->type = GTP_TPDU; |
| 432 | gtp1->length = htons(payload_len); |
| 433 | gtp1->tid = htonl(pctx->u.v1.o_tei); |
| 434 | |
| 435 | /* TODO: Suppport for extension header, sequence number and N-PDU. |
| 436 | * Update the length field if any of them is available. |
| 437 | */ |
| 438 | } |
| 439 | |
| 440 | struct gtp_pktinfo { |
| 441 | struct sock *sk; |
| 442 | struct iphdr *iph; |
| 443 | struct flowi4 fl4; |
| 444 | struct rtable *rt; |
| 445 | struct pdp_ctx *pctx; |
| 446 | struct net_device *dev; |
| 447 | __be16 gtph_port; |
| 448 | }; |
| 449 | |
| 450 | static void gtp_push_header(struct sk_buff *skb, struct gtp_pktinfo *pktinfo) |
| 451 | { |
| 452 | switch (pktinfo->pctx->gtp_version) { |
| 453 | case GTP_V0: |
| 454 | pktinfo->gtph_port = htons(GTP0_PORT); |
| 455 | gtp0_push_header(skb, pktinfo->pctx); |
| 456 | break; |
| 457 | case GTP_V1: |
| 458 | pktinfo->gtph_port = htons(GTP1U_PORT); |
| 459 | gtp1_push_header(skb, pktinfo->pctx); |
| 460 | break; |
| 461 | } |
| 462 | } |
| 463 | |
| 464 | static inline void gtp_set_pktinfo_ipv4(struct gtp_pktinfo *pktinfo, |
| 465 | struct sock *sk, struct iphdr *iph, |
| 466 | struct pdp_ctx *pctx, struct rtable *rt, |
| 467 | struct flowi4 *fl4, |
| 468 | struct net_device *dev) |
| 469 | { |
| 470 | pktinfo->sk = sk; |
| 471 | pktinfo->iph = iph; |
| 472 | pktinfo->pctx = pctx; |
| 473 | pktinfo->rt = rt; |
| 474 | pktinfo->fl4 = *fl4; |
| 475 | pktinfo->dev = dev; |
| 476 | } |
| 477 | |
| 478 | static int gtp_build_skb_ip4(struct sk_buff *skb, struct net_device *dev, |
| 479 | struct gtp_pktinfo *pktinfo) |
| 480 | { |
| 481 | struct gtp_dev *gtp = netdev_priv(dev); |
| 482 | struct pdp_ctx *pctx; |
| 483 | struct rtable *rt; |
| 484 | struct flowi4 fl4; |
| 485 | struct iphdr *iph; |
| 486 | struct sock *sk; |
| 487 | __be16 df; |
| 488 | int mtu; |
| 489 | |
| 490 | /* Read the IP destination address and resolve the PDP context. |
| 491 | * Prepend PDP header with TEI/TID from PDP ctx. |
| 492 | */ |
| 493 | iph = ip_hdr(skb); |
| 494 | pctx = ipv4_pdp_find(gtp, iph->daddr); |
| 495 | if (!pctx) { |
| 496 | netdev_dbg(dev, "no PDP ctx found for %pI4, skip\n", |
| 497 | &iph->daddr); |
| 498 | return -ENOENT; |
| 499 | } |
| 500 | netdev_dbg(dev, "found PDP context %p\n", pctx); |
| 501 | |
| 502 | switch (pctx->gtp_version) { |
| 503 | case GTP_V0: |
| 504 | if (gtp->sock0) |
| 505 | sk = gtp->sock0->sk; |
| 506 | else |
| 507 | sk = NULL; |
| 508 | break; |
| 509 | case GTP_V1: |
| 510 | if (gtp->sock1u) |
| 511 | sk = gtp->sock1u->sk; |
| 512 | else |
| 513 | sk = NULL; |
| 514 | break; |
| 515 | default: |
| 516 | return -ENOENT; |
| 517 | } |
| 518 | |
| 519 | if (!sk) { |
| 520 | netdev_dbg(dev, "no userspace socket is available, skip\n"); |
| 521 | return -ENOENT; |
| 522 | } |
| 523 | |
| 524 | rt = ip4_route_output_gtp(sock_net(sk), &fl4, gtp->sock0->sk, |
| 525 | pctx->sgsn_addr_ip4.s_addr); |
| 526 | if (IS_ERR(rt)) { |
| 527 | netdev_dbg(dev, "no route to SSGN %pI4\n", |
| 528 | &pctx->sgsn_addr_ip4.s_addr); |
| 529 | dev->stats.tx_carrier_errors++; |
| 530 | goto err; |
| 531 | } |
| 532 | |
| 533 | if (rt->dst.dev == dev) { |
| 534 | netdev_dbg(dev, "circular route to SSGN %pI4\n", |
| 535 | &pctx->sgsn_addr_ip4.s_addr); |
| 536 | dev->stats.collisions++; |
| 537 | goto err_rt; |
| 538 | } |
| 539 | |
| 540 | skb_dst_drop(skb); |
| 541 | |
| 542 | /* This is similar to tnl_update_pmtu(). */ |
| 543 | df = iph->frag_off; |
| 544 | if (df) { |
| 545 | mtu = dst_mtu(&rt->dst) - dev->hard_header_len - |
| 546 | sizeof(struct iphdr) - sizeof(struct udphdr); |
| 547 | switch (pctx->gtp_version) { |
| 548 | case GTP_V0: |
| 549 | mtu -= sizeof(struct gtp0_header); |
| 550 | break; |
| 551 | case GTP_V1: |
| 552 | mtu -= sizeof(struct gtp1_header); |
| 553 | break; |
| 554 | } |
| 555 | } else { |
| 556 | mtu = dst_mtu(&rt->dst); |
| 557 | } |
| 558 | |
| 559 | rt->dst.ops->update_pmtu(&rt->dst, NULL, skb, mtu); |
| 560 | |
| 561 | if (!skb_is_gso(skb) && (iph->frag_off & htons(IP_DF)) && |
| 562 | mtu < ntohs(iph->tot_len)) { |
| 563 | netdev_dbg(dev, "packet too big, fragmentation needed\n"); |
| 564 | memset(IPCB(skb), 0, sizeof(*IPCB(skb))); |
| 565 | icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, |
| 566 | htonl(mtu)); |
| 567 | goto err_rt; |
| 568 | } |
| 569 | |
| 570 | gtp_set_pktinfo_ipv4(pktinfo, sk, iph, pctx, rt, &fl4, dev); |
| 571 | gtp_push_header(skb, pktinfo); |
| 572 | |
| 573 | return 0; |
| 574 | err_rt: |
| 575 | ip_rt_put(rt); |
| 576 | err: |
| 577 | return -EBADMSG; |
| 578 | } |
| 579 | |
| 580 | static netdev_tx_t gtp_dev_xmit(struct sk_buff *skb, struct net_device *dev) |
| 581 | { |
| 582 | unsigned int proto = ntohs(skb->protocol); |
| 583 | struct gtp_pktinfo pktinfo; |
| 584 | int err; |
| 585 | |
| 586 | /* Ensure there is sufficient headroom. */ |
| 587 | if (skb_cow_head(skb, dev->needed_headroom)) |
| 588 | goto tx_err; |
| 589 | |
| 590 | skb_reset_inner_headers(skb); |
| 591 | |
| 592 | /* PDP context lookups in gtp_build_skb_*() need rcu read-side lock. */ |
| 593 | rcu_read_lock(); |
| 594 | switch (proto) { |
| 595 | case ETH_P_IP: |
| 596 | err = gtp_build_skb_ip4(skb, dev, &pktinfo); |
| 597 | break; |
| 598 | default: |
| 599 | err = -EOPNOTSUPP; |
| 600 | break; |
| 601 | } |
| 602 | rcu_read_unlock(); |
| 603 | |
| 604 | if (err < 0) |
| 605 | goto tx_err; |
| 606 | |
| 607 | switch (proto) { |
| 608 | case ETH_P_IP: |
| 609 | netdev_dbg(pktinfo.dev, "gtp -> IP src: %pI4 dst: %pI4\n", |
| 610 | &pktinfo.iph->saddr, &pktinfo.iph->daddr); |
| 611 | udp_tunnel_xmit_skb(pktinfo.rt, pktinfo.sk, skb, |
| 612 | pktinfo.fl4.saddr, pktinfo.fl4.daddr, |
| 613 | pktinfo.iph->tos, |
| 614 | ip4_dst_hoplimit(&pktinfo.rt->dst), |
| 615 | htons(IP_DF), |
| 616 | pktinfo.gtph_port, pktinfo.gtph_port, |
| 617 | true, false); |
| 618 | break; |
| 619 | } |
| 620 | |
| 621 | return NETDEV_TX_OK; |
| 622 | tx_err: |
| 623 | dev->stats.tx_errors++; |
| 624 | dev_kfree_skb(skb); |
| 625 | return NETDEV_TX_OK; |
| 626 | } |
| 627 | |
| 628 | static const struct net_device_ops gtp_netdev_ops = { |
| 629 | .ndo_init = gtp_dev_init, |
| 630 | .ndo_uninit = gtp_dev_uninit, |
| 631 | .ndo_start_xmit = gtp_dev_xmit, |
| 632 | .ndo_get_stats64 = ip_tunnel_get_stats64, |
| 633 | }; |
| 634 | |
| 635 | static void gtp_link_setup(struct net_device *dev) |
| 636 | { |
| 637 | dev->netdev_ops = >p_netdev_ops; |
| 638 | dev->destructor = free_netdev; |
| 639 | |
| 640 | dev->hard_header_len = 0; |
| 641 | dev->addr_len = 0; |
| 642 | |
| 643 | /* Zero header length. */ |
| 644 | dev->type = ARPHRD_NONE; |
| 645 | dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST; |
| 646 | |
| 647 | dev->priv_flags |= IFF_NO_QUEUE; |
| 648 | dev->features |= NETIF_F_LLTX; |
| 649 | netif_keep_dst(dev); |
| 650 | |
| 651 | /* Assume largest header, ie. GTPv0. */ |
| 652 | dev->needed_headroom = LL_MAX_HEADER + |
| 653 | sizeof(struct iphdr) + |
| 654 | sizeof(struct udphdr) + |
| 655 | sizeof(struct gtp0_header); |
| 656 | } |
| 657 | |
| 658 | static int gtp_hashtable_new(struct gtp_dev *gtp, int hsize); |
| 659 | static void gtp_hashtable_free(struct gtp_dev *gtp); |
| 660 | static int gtp_encap_enable(struct net_device *dev, struct gtp_dev *gtp, |
| 661 | int fd_gtp0, int fd_gtp1, struct net *src_net); |
| 662 | |
| 663 | static int gtp_newlink(struct net *src_net, struct net_device *dev, |
| 664 | struct nlattr *tb[], struct nlattr *data[]) |
| 665 | { |
| 666 | int hashsize, err, fd0, fd1; |
| 667 | struct gtp_dev *gtp; |
| 668 | struct gtp_net *gn; |
| 669 | |
| 670 | if (!data[IFLA_GTP_FD0] || !data[IFLA_GTP_FD1]) |
| 671 | return -EINVAL; |
| 672 | |
| 673 | gtp = netdev_priv(dev); |
| 674 | |
| 675 | fd0 = nla_get_u32(data[IFLA_GTP_FD0]); |
| 676 | fd1 = nla_get_u32(data[IFLA_GTP_FD1]); |
| 677 | |
| 678 | err = gtp_encap_enable(dev, gtp, fd0, fd1, src_net); |
| 679 | if (err < 0) |
| 680 | goto out_err; |
| 681 | |
| 682 | if (!data[IFLA_GTP_PDP_HASHSIZE]) |
| 683 | hashsize = 1024; |
| 684 | else |
| 685 | hashsize = nla_get_u32(data[IFLA_GTP_PDP_HASHSIZE]); |
| 686 | |
| 687 | err = gtp_hashtable_new(gtp, hashsize); |
| 688 | if (err < 0) |
| 689 | goto out_encap; |
| 690 | |
| 691 | err = register_netdevice(dev); |
| 692 | if (err < 0) { |
| 693 | netdev_dbg(dev, "failed to register new netdev %d\n", err); |
| 694 | goto out_hashtable; |
| 695 | } |
| 696 | |
| 697 | gn = net_generic(dev_net(dev), gtp_net_id); |
| 698 | list_add_rcu(>p->list, &gn->gtp_dev_list); |
| 699 | |
| 700 | netdev_dbg(dev, "registered new GTP interface\n"); |
| 701 | |
| 702 | return 0; |
| 703 | |
| 704 | out_hashtable: |
| 705 | gtp_hashtable_free(gtp); |
| 706 | out_encap: |
| 707 | gtp_encap_disable(gtp); |
| 708 | out_err: |
| 709 | return err; |
| 710 | } |
| 711 | |
| 712 | static void gtp_dellink(struct net_device *dev, struct list_head *head) |
| 713 | { |
| 714 | struct gtp_dev *gtp = netdev_priv(dev); |
| 715 | |
| 716 | gtp_encap_disable(gtp); |
| 717 | gtp_hashtable_free(gtp); |
| 718 | list_del_rcu(>p->list); |
| 719 | unregister_netdevice_queue(dev, head); |
| 720 | } |
| 721 | |
| 722 | static const struct nla_policy gtp_policy[IFLA_GTP_MAX + 1] = { |
| 723 | [IFLA_GTP_FD0] = { .type = NLA_U32 }, |
| 724 | [IFLA_GTP_FD1] = { .type = NLA_U32 }, |
| 725 | [IFLA_GTP_PDP_HASHSIZE] = { .type = NLA_U32 }, |
| 726 | }; |
| 727 | |
| 728 | static int gtp_validate(struct nlattr *tb[], struct nlattr *data[]) |
| 729 | { |
| 730 | if (!data) |
| 731 | return -EINVAL; |
| 732 | |
| 733 | return 0; |
| 734 | } |
| 735 | |
| 736 | static size_t gtp_get_size(const struct net_device *dev) |
| 737 | { |
| 738 | return nla_total_size(sizeof(__u32)); /* IFLA_GTP_PDP_HASHSIZE */ |
| 739 | } |
| 740 | |
| 741 | static int gtp_fill_info(struct sk_buff *skb, const struct net_device *dev) |
| 742 | { |
| 743 | struct gtp_dev *gtp = netdev_priv(dev); |
| 744 | |
| 745 | if (nla_put_u32(skb, IFLA_GTP_PDP_HASHSIZE, gtp->hash_size)) |
| 746 | goto nla_put_failure; |
| 747 | |
| 748 | return 0; |
| 749 | |
| 750 | nla_put_failure: |
| 751 | return -EMSGSIZE; |
| 752 | } |
| 753 | |
| 754 | static struct rtnl_link_ops gtp_link_ops __read_mostly = { |
| 755 | .kind = "gtp", |
| 756 | .maxtype = IFLA_GTP_MAX, |
| 757 | .policy = gtp_policy, |
| 758 | .priv_size = sizeof(struct gtp_dev), |
| 759 | .setup = gtp_link_setup, |
| 760 | .validate = gtp_validate, |
| 761 | .newlink = gtp_newlink, |
| 762 | .dellink = gtp_dellink, |
| 763 | .get_size = gtp_get_size, |
| 764 | .fill_info = gtp_fill_info, |
| 765 | }; |
| 766 | |
| 767 | static struct net *gtp_genl_get_net(struct net *src_net, struct nlattr *tb[]) |
| 768 | { |
| 769 | struct net *net; |
| 770 | |
| 771 | /* Examine the link attributes and figure out which network namespace |
| 772 | * we are talking about. |
| 773 | */ |
| 774 | if (tb[GTPA_NET_NS_FD]) |
| 775 | net = get_net_ns_by_fd(nla_get_u32(tb[GTPA_NET_NS_FD])); |
| 776 | else |
| 777 | net = get_net(src_net); |
| 778 | |
| 779 | return net; |
| 780 | } |
| 781 | |
| 782 | static int gtp_hashtable_new(struct gtp_dev *gtp, int hsize) |
| 783 | { |
| 784 | int i; |
| 785 | |
| 786 | gtp->addr_hash = kmalloc(sizeof(struct hlist_head) * hsize, GFP_KERNEL); |
| 787 | if (gtp->addr_hash == NULL) |
| 788 | return -ENOMEM; |
| 789 | |
| 790 | gtp->tid_hash = kmalloc(sizeof(struct hlist_head) * hsize, GFP_KERNEL); |
| 791 | if (gtp->tid_hash == NULL) |
| 792 | goto err1; |
| 793 | |
| 794 | gtp->hash_size = hsize; |
| 795 | |
| 796 | for (i = 0; i < hsize; i++) { |
| 797 | INIT_HLIST_HEAD(>p->addr_hash[i]); |
| 798 | INIT_HLIST_HEAD(>p->tid_hash[i]); |
| 799 | } |
| 800 | return 0; |
| 801 | err1: |
| 802 | kfree(gtp->addr_hash); |
| 803 | return -ENOMEM; |
| 804 | } |
| 805 | |
| 806 | static void gtp_hashtable_free(struct gtp_dev *gtp) |
| 807 | { |
| 808 | struct pdp_ctx *pctx; |
| 809 | int i; |
| 810 | |
| 811 | for (i = 0; i < gtp->hash_size; i++) { |
| 812 | hlist_for_each_entry_rcu(pctx, >p->tid_hash[i], hlist_tid) { |
| 813 | hlist_del_rcu(&pctx->hlist_tid); |
| 814 | hlist_del_rcu(&pctx->hlist_addr); |
| 815 | kfree_rcu(pctx, rcu_head); |
| 816 | } |
| 817 | } |
| 818 | synchronize_rcu(); |
| 819 | kfree(gtp->addr_hash); |
| 820 | kfree(gtp->tid_hash); |
| 821 | } |
| 822 | |
| 823 | static int gtp_encap_enable(struct net_device *dev, struct gtp_dev *gtp, |
| 824 | int fd_gtp0, int fd_gtp1, struct net *src_net) |
| 825 | { |
| 826 | struct udp_tunnel_sock_cfg tuncfg = {NULL}; |
| 827 | struct socket *sock0, *sock1u; |
| 828 | int err; |
| 829 | |
| 830 | netdev_dbg(dev, "enable gtp on %d, %d\n", fd_gtp0, fd_gtp1); |
| 831 | |
| 832 | sock0 = sockfd_lookup(fd_gtp0, &err); |
| 833 | if (sock0 == NULL) { |
| 834 | netdev_dbg(dev, "socket fd=%d not found (gtp0)\n", fd_gtp0); |
| 835 | return -ENOENT; |
| 836 | } |
| 837 | |
| 838 | if (sock0->sk->sk_protocol != IPPROTO_UDP) { |
| 839 | netdev_dbg(dev, "socket fd=%d not UDP\n", fd_gtp0); |
| 840 | err = -EINVAL; |
| 841 | goto err1; |
| 842 | } |
| 843 | |
| 844 | sock1u = sockfd_lookup(fd_gtp1, &err); |
| 845 | if (sock1u == NULL) { |
| 846 | netdev_dbg(dev, "socket fd=%d not found (gtp1u)\n", fd_gtp1); |
| 847 | err = -ENOENT; |
| 848 | goto err1; |
| 849 | } |
| 850 | |
| 851 | if (sock1u->sk->sk_protocol != IPPROTO_UDP) { |
| 852 | netdev_dbg(dev, "socket fd=%d not UDP\n", fd_gtp1); |
| 853 | err = -EINVAL; |
| 854 | goto err2; |
| 855 | } |
| 856 | |
| 857 | netdev_dbg(dev, "enable gtp on %p, %p\n", sock0, sock1u); |
| 858 | |
| 859 | gtp->sock0 = sock0; |
| 860 | gtp->sock1u = sock1u; |
| 861 | gtp->net = src_net; |
| 862 | |
| 863 | tuncfg.sk_user_data = gtp; |
| 864 | tuncfg.encap_rcv = gtp_encap_recv; |
| 865 | tuncfg.encap_destroy = gtp_encap_destroy; |
| 866 | |
| 867 | tuncfg.encap_type = UDP_ENCAP_GTP0; |
| 868 | setup_udp_tunnel_sock(sock_net(gtp->sock0->sk), gtp->sock0, &tuncfg); |
| 869 | |
| 870 | tuncfg.encap_type = UDP_ENCAP_GTP1U; |
| 871 | setup_udp_tunnel_sock(sock_net(gtp->sock1u->sk), gtp->sock1u, &tuncfg); |
| 872 | |
| 873 | err = 0; |
| 874 | err2: |
| 875 | sockfd_put(sock1u); |
| 876 | err1: |
| 877 | sockfd_put(sock0); |
| 878 | return err; |
| 879 | } |
| 880 | |
| 881 | static struct net_device *gtp_find_dev(struct net *net, int ifindex) |
| 882 | { |
| 883 | struct gtp_net *gn = net_generic(net, gtp_net_id); |
| 884 | struct gtp_dev *gtp; |
| 885 | |
| 886 | list_for_each_entry_rcu(gtp, &gn->gtp_dev_list, list) { |
| 887 | if (ifindex == gtp->dev->ifindex) |
| 888 | return gtp->dev; |
| 889 | } |
| 890 | return NULL; |
| 891 | } |
| 892 | |
| 893 | static void ipv4_pdp_fill(struct pdp_ctx *pctx, struct genl_info *info) |
| 894 | { |
| 895 | pctx->gtp_version = nla_get_u32(info->attrs[GTPA_VERSION]); |
| 896 | pctx->af = AF_INET; |
| 897 | pctx->sgsn_addr_ip4.s_addr = |
| 898 | nla_get_be32(info->attrs[GTPA_SGSN_ADDRESS]); |
| 899 | pctx->ms_addr_ip4.s_addr = |
| 900 | nla_get_be32(info->attrs[GTPA_MS_ADDRESS]); |
| 901 | |
| 902 | switch (pctx->gtp_version) { |
| 903 | case GTP_V0: |
| 904 | /* According to TS 09.60, sections 7.5.1 and 7.5.2, the flow |
| 905 | * label needs to be the same for uplink and downlink packets, |
| 906 | * so let's annotate this. |
| 907 | */ |
| 908 | pctx->u.v0.tid = nla_get_u64(info->attrs[GTPA_TID]); |
| 909 | pctx->u.v0.flow = nla_get_u16(info->attrs[GTPA_FLOW]); |
| 910 | break; |
| 911 | case GTP_V1: |
| 912 | pctx->u.v1.i_tei = nla_get_u32(info->attrs[GTPA_I_TEI]); |
| 913 | pctx->u.v1.o_tei = nla_get_u32(info->attrs[GTPA_O_TEI]); |
| 914 | break; |
| 915 | default: |
| 916 | break; |
| 917 | } |
| 918 | } |
| 919 | |
| 920 | static int ipv4_pdp_add(struct net_device *dev, struct genl_info *info) |
| 921 | { |
| 922 | struct gtp_dev *gtp = netdev_priv(dev); |
| 923 | u32 hash_ms, hash_tid = 0; |
| 924 | struct pdp_ctx *pctx; |
| 925 | bool found = false; |
| 926 | __be32 ms_addr; |
| 927 | |
| 928 | ms_addr = nla_get_be32(info->attrs[GTPA_MS_ADDRESS]); |
| 929 | hash_ms = ipv4_hashfn(ms_addr) % gtp->hash_size; |
| 930 | |
| 931 | hlist_for_each_entry_rcu(pctx, >p->addr_hash[hash_ms], hlist_addr) { |
| 932 | if (pctx->ms_addr_ip4.s_addr == ms_addr) { |
| 933 | found = true; |
| 934 | break; |
| 935 | } |
| 936 | } |
| 937 | |
| 938 | if (found) { |
| 939 | if (info->nlhdr->nlmsg_flags & NLM_F_EXCL) |
| 940 | return -EEXIST; |
| 941 | if (info->nlhdr->nlmsg_flags & NLM_F_REPLACE) |
| 942 | return -EOPNOTSUPP; |
| 943 | |
| 944 | ipv4_pdp_fill(pctx, info); |
| 945 | |
| 946 | if (pctx->gtp_version == GTP_V0) |
| 947 | netdev_dbg(dev, "GTPv0-U: update tunnel id = %llx (pdp %p)\n", |
| 948 | pctx->u.v0.tid, pctx); |
| 949 | else if (pctx->gtp_version == GTP_V1) |
| 950 | netdev_dbg(dev, "GTPv1-U: update tunnel id = %x/%x (pdp %p)\n", |
| 951 | pctx->u.v1.i_tei, pctx->u.v1.o_tei, pctx); |
| 952 | |
| 953 | return 0; |
| 954 | |
| 955 | } |
| 956 | |
| 957 | pctx = kmalloc(sizeof(struct pdp_ctx), GFP_KERNEL); |
| 958 | if (pctx == NULL) |
| 959 | return -ENOMEM; |
| 960 | |
| 961 | ipv4_pdp_fill(pctx, info); |
| 962 | atomic_set(&pctx->tx_seq, 0); |
| 963 | |
| 964 | switch (pctx->gtp_version) { |
| 965 | case GTP_V0: |
| 966 | /* TS 09.60: "The flow label identifies unambiguously a GTP |
| 967 | * flow.". We use the tid for this instead, I cannot find a |
| 968 | * situation in which this doesn't unambiguosly identify the |
| 969 | * PDP context. |
| 970 | */ |
| 971 | hash_tid = gtp0_hashfn(pctx->u.v0.tid) % gtp->hash_size; |
| 972 | break; |
| 973 | case GTP_V1: |
| 974 | hash_tid = gtp1u_hashfn(pctx->u.v1.i_tei) % gtp->hash_size; |
| 975 | break; |
| 976 | } |
| 977 | |
| 978 | hlist_add_head_rcu(&pctx->hlist_addr, >p->addr_hash[hash_ms]); |
| 979 | hlist_add_head_rcu(&pctx->hlist_tid, >p->tid_hash[hash_tid]); |
| 980 | |
| 981 | switch (pctx->gtp_version) { |
| 982 | case GTP_V0: |
| 983 | netdev_dbg(dev, "GTPv0-U: new PDP ctx id=%llx ssgn=%pI4 ms=%pI4 (pdp=%p)\n", |
| 984 | pctx->u.v0.tid, &pctx->sgsn_addr_ip4, |
| 985 | &pctx->ms_addr_ip4, pctx); |
| 986 | break; |
| 987 | case GTP_V1: |
| 988 | netdev_dbg(dev, "GTPv1-U: new PDP ctx id=%x/%x ssgn=%pI4 ms=%pI4 (pdp=%p)\n", |
| 989 | pctx->u.v1.i_tei, pctx->u.v1.o_tei, |
| 990 | &pctx->sgsn_addr_ip4, &pctx->ms_addr_ip4, pctx); |
| 991 | break; |
| 992 | } |
| 993 | |
| 994 | return 0; |
| 995 | } |
| 996 | |
| 997 | static int gtp_genl_new_pdp(struct sk_buff *skb, struct genl_info *info) |
| 998 | { |
| 999 | struct net_device *dev; |
| 1000 | struct net *net; |
| 1001 | |
| 1002 | if (!info->attrs[GTPA_VERSION] || |
| 1003 | !info->attrs[GTPA_LINK] || |
| 1004 | !info->attrs[GTPA_SGSN_ADDRESS] || |
| 1005 | !info->attrs[GTPA_MS_ADDRESS]) |
| 1006 | return -EINVAL; |
| 1007 | |
| 1008 | switch (nla_get_u32(info->attrs[GTPA_VERSION])) { |
| 1009 | case GTP_V0: |
| 1010 | if (!info->attrs[GTPA_TID] || |
| 1011 | !info->attrs[GTPA_FLOW]) |
| 1012 | return -EINVAL; |
| 1013 | break; |
| 1014 | case GTP_V1: |
| 1015 | if (!info->attrs[GTPA_I_TEI] || |
| 1016 | !info->attrs[GTPA_O_TEI]) |
| 1017 | return -EINVAL; |
| 1018 | break; |
| 1019 | |
| 1020 | default: |
| 1021 | return -EINVAL; |
| 1022 | } |
| 1023 | |
| 1024 | net = gtp_genl_get_net(sock_net(skb->sk), info->attrs); |
| 1025 | if (IS_ERR(net)) |
| 1026 | return PTR_ERR(net); |
| 1027 | |
| 1028 | /* Check if there's an existing gtpX device to configure */ |
| 1029 | dev = gtp_find_dev(net, nla_get_u32(info->attrs[GTPA_LINK])); |
Pablo Neira | 27ee441 | 2016-05-12 17:16:31 +0200 | [diff] [blame] | 1030 | if (dev == NULL) { |
| 1031 | put_net(net); |
Pablo Neira | 459aa66 | 2016-05-09 00:55:48 +0200 | [diff] [blame] | 1032 | return -ENODEV; |
Pablo Neira | 27ee441 | 2016-05-12 17:16:31 +0200 | [diff] [blame] | 1033 | } |
| 1034 | put_net(net); |
Pablo Neira | 459aa66 | 2016-05-09 00:55:48 +0200 | [diff] [blame] | 1035 | |
| 1036 | return ipv4_pdp_add(dev, info); |
| 1037 | } |
| 1038 | |
| 1039 | static int gtp_genl_del_pdp(struct sk_buff *skb, struct genl_info *info) |
| 1040 | { |
| 1041 | struct net_device *dev; |
| 1042 | struct pdp_ctx *pctx; |
| 1043 | struct gtp_dev *gtp; |
| 1044 | struct net *net; |
| 1045 | |
| 1046 | if (!info->attrs[GTPA_VERSION] || |
| 1047 | !info->attrs[GTPA_LINK]) |
| 1048 | return -EINVAL; |
| 1049 | |
| 1050 | net = gtp_genl_get_net(sock_net(skb->sk), info->attrs); |
| 1051 | if (IS_ERR(net)) |
| 1052 | return PTR_ERR(net); |
| 1053 | |
| 1054 | /* Check if there's an existing gtpX device to configure */ |
| 1055 | dev = gtp_find_dev(net, nla_get_u32(info->attrs[GTPA_LINK])); |
Pablo Neira | 27ee441 | 2016-05-12 17:16:31 +0200 | [diff] [blame] | 1056 | if (dev == NULL) { |
| 1057 | put_net(net); |
Pablo Neira | 459aa66 | 2016-05-09 00:55:48 +0200 | [diff] [blame] | 1058 | return -ENODEV; |
Pablo Neira | 27ee441 | 2016-05-12 17:16:31 +0200 | [diff] [blame] | 1059 | } |
| 1060 | put_net(net); |
Pablo Neira | 459aa66 | 2016-05-09 00:55:48 +0200 | [diff] [blame] | 1061 | |
| 1062 | gtp = netdev_priv(dev); |
| 1063 | |
| 1064 | switch (nla_get_u32(info->attrs[GTPA_VERSION])) { |
| 1065 | case GTP_V0: |
| 1066 | if (!info->attrs[GTPA_TID]) |
| 1067 | return -EINVAL; |
| 1068 | pctx = gtp0_pdp_find(gtp, nla_get_u64(info->attrs[GTPA_TID])); |
| 1069 | break; |
| 1070 | case GTP_V1: |
| 1071 | if (!info->attrs[GTPA_I_TEI]) |
| 1072 | return -EINVAL; |
| 1073 | pctx = gtp1_pdp_find(gtp, nla_get_u64(info->attrs[GTPA_I_TEI])); |
| 1074 | break; |
| 1075 | |
| 1076 | default: |
| 1077 | return -EINVAL; |
| 1078 | } |
| 1079 | |
| 1080 | if (pctx == NULL) |
| 1081 | return -ENOENT; |
| 1082 | |
| 1083 | if (pctx->gtp_version == GTP_V0) |
| 1084 | netdev_dbg(dev, "GTPv0-U: deleting tunnel id = %llx (pdp %p)\n", |
| 1085 | pctx->u.v0.tid, pctx); |
| 1086 | else if (pctx->gtp_version == GTP_V1) |
| 1087 | netdev_dbg(dev, "GTPv1-U: deleting tunnel id = %x/%x (pdp %p)\n", |
| 1088 | pctx->u.v1.i_tei, pctx->u.v1.o_tei, pctx); |
| 1089 | |
| 1090 | hlist_del_rcu(&pctx->hlist_tid); |
| 1091 | hlist_del_rcu(&pctx->hlist_addr); |
| 1092 | kfree_rcu(pctx, rcu_head); |
| 1093 | |
| 1094 | return 0; |
| 1095 | } |
| 1096 | |
| 1097 | static struct genl_family gtp_genl_family = { |
| 1098 | .id = GENL_ID_GENERATE, |
| 1099 | .name = "gtp", |
| 1100 | .version = 0, |
| 1101 | .hdrsize = 0, |
| 1102 | .maxattr = GTPA_MAX, |
| 1103 | .netnsok = true, |
| 1104 | }; |
| 1105 | |
| 1106 | static int gtp_genl_fill_info(struct sk_buff *skb, u32 snd_portid, u32 snd_seq, |
| 1107 | u32 type, struct pdp_ctx *pctx) |
| 1108 | { |
| 1109 | void *genlh; |
| 1110 | |
| 1111 | genlh = genlmsg_put(skb, snd_portid, snd_seq, >p_genl_family, 0, |
| 1112 | type); |
| 1113 | if (genlh == NULL) |
| 1114 | goto nlmsg_failure; |
| 1115 | |
| 1116 | if (nla_put_u32(skb, GTPA_VERSION, pctx->gtp_version) || |
| 1117 | nla_put_be32(skb, GTPA_SGSN_ADDRESS, pctx->sgsn_addr_ip4.s_addr) || |
| 1118 | nla_put_be32(skb, GTPA_MS_ADDRESS, pctx->ms_addr_ip4.s_addr)) |
| 1119 | goto nla_put_failure; |
| 1120 | |
| 1121 | switch (pctx->gtp_version) { |
| 1122 | case GTP_V0: |
| 1123 | if (nla_put_u64_64bit(skb, GTPA_TID, pctx->u.v0.tid, GTPA_PAD) || |
| 1124 | nla_put_u16(skb, GTPA_FLOW, pctx->u.v0.flow)) |
| 1125 | goto nla_put_failure; |
| 1126 | break; |
| 1127 | case GTP_V1: |
| 1128 | if (nla_put_u32(skb, GTPA_I_TEI, pctx->u.v1.i_tei) || |
| 1129 | nla_put_u32(skb, GTPA_O_TEI, pctx->u.v1.o_tei)) |
| 1130 | goto nla_put_failure; |
| 1131 | break; |
| 1132 | } |
| 1133 | genlmsg_end(skb, genlh); |
| 1134 | return 0; |
| 1135 | |
| 1136 | nlmsg_failure: |
| 1137 | nla_put_failure: |
| 1138 | genlmsg_cancel(skb, genlh); |
| 1139 | return -EMSGSIZE; |
| 1140 | } |
| 1141 | |
| 1142 | static int gtp_genl_get_pdp(struct sk_buff *skb, struct genl_info *info) |
| 1143 | { |
| 1144 | struct pdp_ctx *pctx = NULL; |
| 1145 | struct net_device *dev; |
| 1146 | struct sk_buff *skb2; |
| 1147 | struct gtp_dev *gtp; |
| 1148 | u32 gtp_version; |
| 1149 | struct net *net; |
| 1150 | int err; |
| 1151 | |
| 1152 | if (!info->attrs[GTPA_VERSION] || |
| 1153 | !info->attrs[GTPA_LINK]) |
| 1154 | return -EINVAL; |
| 1155 | |
| 1156 | gtp_version = nla_get_u32(info->attrs[GTPA_VERSION]); |
| 1157 | switch (gtp_version) { |
| 1158 | case GTP_V0: |
| 1159 | case GTP_V1: |
| 1160 | break; |
| 1161 | default: |
| 1162 | return -EINVAL; |
| 1163 | } |
| 1164 | |
| 1165 | net = gtp_genl_get_net(sock_net(skb->sk), info->attrs); |
| 1166 | if (IS_ERR(net)) |
| 1167 | return PTR_ERR(net); |
| 1168 | |
| 1169 | /* Check if there's an existing gtpX device to configure */ |
| 1170 | dev = gtp_find_dev(net, nla_get_u32(info->attrs[GTPA_LINK])); |
Pablo Neira | 27ee441 | 2016-05-12 17:16:31 +0200 | [diff] [blame] | 1171 | if (dev == NULL) { |
| 1172 | put_net(net); |
Pablo Neira | 459aa66 | 2016-05-09 00:55:48 +0200 | [diff] [blame] | 1173 | return -ENODEV; |
Pablo Neira | 27ee441 | 2016-05-12 17:16:31 +0200 | [diff] [blame] | 1174 | } |
| 1175 | put_net(net); |
Pablo Neira | 459aa66 | 2016-05-09 00:55:48 +0200 | [diff] [blame] | 1176 | |
| 1177 | gtp = netdev_priv(dev); |
| 1178 | |
| 1179 | rcu_read_lock(); |
| 1180 | if (gtp_version == GTP_V0 && |
| 1181 | info->attrs[GTPA_TID]) { |
| 1182 | u64 tid = nla_get_u64(info->attrs[GTPA_TID]); |
| 1183 | |
| 1184 | pctx = gtp0_pdp_find(gtp, tid); |
| 1185 | } else if (gtp_version == GTP_V1 && |
| 1186 | info->attrs[GTPA_I_TEI]) { |
| 1187 | u32 tid = nla_get_u32(info->attrs[GTPA_I_TEI]); |
| 1188 | |
| 1189 | pctx = gtp1_pdp_find(gtp, tid); |
| 1190 | } else if (info->attrs[GTPA_MS_ADDRESS]) { |
| 1191 | __be32 ip = nla_get_be32(info->attrs[GTPA_MS_ADDRESS]); |
| 1192 | |
| 1193 | pctx = ipv4_pdp_find(gtp, ip); |
| 1194 | } |
| 1195 | |
| 1196 | if (pctx == NULL) { |
| 1197 | err = -ENOENT; |
| 1198 | goto err_unlock; |
| 1199 | } |
| 1200 | |
| 1201 | skb2 = genlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC); |
| 1202 | if (skb2 == NULL) { |
| 1203 | err = -ENOMEM; |
| 1204 | goto err_unlock; |
| 1205 | } |
| 1206 | |
| 1207 | err = gtp_genl_fill_info(skb2, NETLINK_CB(skb).portid, |
| 1208 | info->snd_seq, info->nlhdr->nlmsg_type, pctx); |
| 1209 | if (err < 0) |
| 1210 | goto err_unlock_free; |
| 1211 | |
| 1212 | rcu_read_unlock(); |
| 1213 | return genlmsg_unicast(genl_info_net(info), skb2, info->snd_portid); |
| 1214 | |
| 1215 | err_unlock_free: |
| 1216 | kfree_skb(skb2); |
| 1217 | err_unlock: |
| 1218 | rcu_read_unlock(); |
| 1219 | return err; |
| 1220 | } |
| 1221 | |
| 1222 | static int gtp_genl_dump_pdp(struct sk_buff *skb, |
| 1223 | struct netlink_callback *cb) |
| 1224 | { |
| 1225 | struct gtp_dev *last_gtp = (struct gtp_dev *)cb->args[2], *gtp; |
| 1226 | struct net *net = sock_net(skb->sk); |
| 1227 | struct gtp_net *gn = net_generic(net, gtp_net_id); |
| 1228 | unsigned long tid = cb->args[1]; |
| 1229 | int i, k = cb->args[0], ret; |
| 1230 | struct pdp_ctx *pctx; |
| 1231 | |
| 1232 | if (cb->args[4]) |
| 1233 | return 0; |
| 1234 | |
| 1235 | list_for_each_entry_rcu(gtp, &gn->gtp_dev_list, list) { |
| 1236 | if (last_gtp && last_gtp != gtp) |
| 1237 | continue; |
| 1238 | else |
| 1239 | last_gtp = NULL; |
| 1240 | |
| 1241 | for (i = k; i < gtp->hash_size; i++) { |
| 1242 | hlist_for_each_entry_rcu(pctx, >p->tid_hash[i], hlist_tid) { |
| 1243 | if (tid && tid != pctx->u.tid) |
| 1244 | continue; |
| 1245 | else |
| 1246 | tid = 0; |
| 1247 | |
| 1248 | ret = gtp_genl_fill_info(skb, |
| 1249 | NETLINK_CB(cb->skb).portid, |
| 1250 | cb->nlh->nlmsg_seq, |
| 1251 | cb->nlh->nlmsg_type, pctx); |
| 1252 | if (ret < 0) { |
| 1253 | cb->args[0] = i; |
| 1254 | cb->args[1] = pctx->u.tid; |
| 1255 | cb->args[2] = (unsigned long)gtp; |
| 1256 | goto out; |
| 1257 | } |
| 1258 | } |
| 1259 | } |
| 1260 | } |
| 1261 | cb->args[4] = 1; |
| 1262 | out: |
| 1263 | return skb->len; |
| 1264 | } |
| 1265 | |
| 1266 | static struct nla_policy gtp_genl_policy[GTPA_MAX + 1] = { |
| 1267 | [GTPA_LINK] = { .type = NLA_U32, }, |
| 1268 | [GTPA_VERSION] = { .type = NLA_U32, }, |
| 1269 | [GTPA_TID] = { .type = NLA_U64, }, |
| 1270 | [GTPA_SGSN_ADDRESS] = { .type = NLA_U32, }, |
| 1271 | [GTPA_MS_ADDRESS] = { .type = NLA_U32, }, |
| 1272 | [GTPA_FLOW] = { .type = NLA_U16, }, |
| 1273 | [GTPA_NET_NS_FD] = { .type = NLA_U32, }, |
| 1274 | [GTPA_I_TEI] = { .type = NLA_U32, }, |
| 1275 | [GTPA_O_TEI] = { .type = NLA_U32, }, |
| 1276 | }; |
| 1277 | |
| 1278 | static const struct genl_ops gtp_genl_ops[] = { |
| 1279 | { |
| 1280 | .cmd = GTP_CMD_NEWPDP, |
| 1281 | .doit = gtp_genl_new_pdp, |
| 1282 | .policy = gtp_genl_policy, |
| 1283 | .flags = GENL_ADMIN_PERM, |
| 1284 | }, |
| 1285 | { |
| 1286 | .cmd = GTP_CMD_DELPDP, |
| 1287 | .doit = gtp_genl_del_pdp, |
| 1288 | .policy = gtp_genl_policy, |
| 1289 | .flags = GENL_ADMIN_PERM, |
| 1290 | }, |
| 1291 | { |
| 1292 | .cmd = GTP_CMD_GETPDP, |
| 1293 | .doit = gtp_genl_get_pdp, |
| 1294 | .dumpit = gtp_genl_dump_pdp, |
| 1295 | .policy = gtp_genl_policy, |
| 1296 | .flags = GENL_ADMIN_PERM, |
| 1297 | }, |
| 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_with_ops(>p_genl_family, gtp_genl_ops); |
| 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"); |
Andreas Schultz | eb84641 | 2017-01-27 10:40:56 +0100 | [diff] [blame] | 1375 | MODULE_ALIAS_GENL_FAMILY("gtp"); |