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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. */
36struct 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. */
65struct 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
79static unsigned int gtp_net_id __read_mostly;
80
81struct gtp_net {
82 struct list_head gtp_dev_list;
83};
84
85static u32 gtp_h_initval;
86
87static void pdp_context_delete(struct pdp_ctx *pctx);
88
89static 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
95static inline u32 gtp1u_hashfn(u32 tid)
96{
97 return jhash_1word(tid, gtp_h_initval);
98}
99
100static 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. */
106static 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. */
122static 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. */
138static 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
154static 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 */
173static 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
183static 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. */
219static 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
246static 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
288static void __gtp_encap_destroy(struct sock *sk)
289{
290 struct gtp_dev *gtp;
291
292 lock_sock(sk);
293 gtp = sk->sk_user_data;
294 if (gtp) {
295 if (gtp->sk0 == sk)
296 gtp->sk0 = NULL;
297 else
298 gtp->sk1u = NULL;
299 udp_sk(sk)->encap_type = 0;
300 rcu_assign_sk_user_data(sk, NULL);
301 sock_put(sk);
302 }
303 release_sock(sk);
304}
305
306static void gtp_encap_destroy(struct sock *sk)
307{
308 rtnl_lock();
309 __gtp_encap_destroy(sk);
310 rtnl_unlock();
311}
312
313static void gtp_encap_disable_sock(struct sock *sk)
314{
315 if (!sk)
316 return;
317
318 __gtp_encap_destroy(sk);
319}
320
321static void gtp_encap_disable(struct gtp_dev *gtp)
322{
323 gtp_encap_disable_sock(gtp->sk0);
324 gtp_encap_disable_sock(gtp->sk1u);
325}
326
327/* UDP encapsulation receive handler. See net/ipv4/udp.c.
328 * Return codes: 0: success, <0: error, >0: pass up to userspace UDP socket.
329 */
330static int gtp_encap_recv(struct sock *sk, struct sk_buff *skb)
331{
332 struct gtp_dev *gtp;
333 int ret = 0;
334
335 gtp = rcu_dereference_sk_user_data(sk);
336 if (!gtp)
337 return 1;
338
339 netdev_dbg(gtp->dev, "encap_recv sk=%p\n", sk);
340
341 switch (udp_sk(sk)->encap_type) {
342 case UDP_ENCAP_GTP0:
343 netdev_dbg(gtp->dev, "received GTP0 packet\n");
344 ret = gtp0_udp_encap_recv(gtp, skb);
345 break;
346 case UDP_ENCAP_GTP1U:
347 netdev_dbg(gtp->dev, "received GTP1U packet\n");
348 ret = gtp1u_udp_encap_recv(gtp, skb);
349 break;
350 default:
351 ret = -1; /* Shouldn't happen. */
352 }
353
354 switch (ret) {
355 case 1:
356 netdev_dbg(gtp->dev, "pass up to the process\n");
357 break;
358 case 0:
359 break;
360 case -1:
361 netdev_dbg(gtp->dev, "GTP packet has been dropped\n");
362 kfree_skb(skb);
363 ret = 0;
364 break;
365 }
366
367 return ret;
368}
369
370static int gtp_dev_init(struct net_device *dev)
371{
372 struct gtp_dev *gtp = netdev_priv(dev);
373
374 gtp->dev = dev;
375
376 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
377 if (!dev->tstats)
378 return -ENOMEM;
379
380 return 0;
381}
382
383static void gtp_dev_uninit(struct net_device *dev)
384{
385 struct gtp_dev *gtp = netdev_priv(dev);
386
387 gtp_encap_disable(gtp);
388 free_percpu(dev->tstats);
389}
390
391static struct rtable *ip4_route_output_gtp(struct flowi4 *fl4,
392 const struct sock *sk,
393 __be32 daddr)
394{
395 memset(fl4, 0, sizeof(*fl4));
396 fl4->flowi4_oif = sk->sk_bound_dev_if;
397 fl4->daddr = daddr;
398 fl4->saddr = inet_sk(sk)->inet_saddr;
399 fl4->flowi4_tos = RT_CONN_FLAGS(sk);
400 fl4->flowi4_proto = sk->sk_protocol;
401
402 return ip_route_output_key(sock_net(sk), fl4);
403}
404
405static inline void gtp0_push_header(struct sk_buff *skb, struct pdp_ctx *pctx)
406{
407 int payload_len = skb->len;
408 struct gtp0_header *gtp0;
409
410 gtp0 = skb_push(skb, sizeof(*gtp0));
411
412 gtp0->flags = 0x1e; /* v0, GTP-non-prime. */
413 gtp0->type = GTP_TPDU;
414 gtp0->length = htons(payload_len);
415 gtp0->seq = htons((atomic_inc_return(&pctx->tx_seq) - 1) % 0xffff);
416 gtp0->flow = htons(pctx->u.v0.flow);
417 gtp0->number = 0xff;
418 gtp0->spare[0] = gtp0->spare[1] = gtp0->spare[2] = 0xff;
419 gtp0->tid = cpu_to_be64(pctx->u.v0.tid);
420}
421
422static inline void gtp1_push_header(struct sk_buff *skb, struct pdp_ctx *pctx)
423{
424 int payload_len = skb->len;
425 struct gtp1_header *gtp1;
426
427 gtp1 = skb_push(skb, sizeof(*gtp1));
428
429 /* Bits 8 7 6 5 4 3 2 1
430 * +--+--+--+--+--+--+--+--+
431 * |version |PT| 0| E| S|PN|
432 * +--+--+--+--+--+--+--+--+
433 * 0 0 1 1 1 0 0 0
434 */
435 gtp1->flags = 0x30; /* v1, GTP-non-prime. */
436 gtp1->type = GTP_TPDU;
437 gtp1->length = htons(payload_len);
438 gtp1->tid = htonl(pctx->u.v1.o_tei);
439
440 /* TODO: Suppport for extension header, sequence number and N-PDU.
441 * Update the length field if any of them is available.
442 */
443}
444
445struct gtp_pktinfo {
446 struct sock *sk;
447 struct iphdr *iph;
448 struct flowi4 fl4;
449 struct rtable *rt;
450 struct pdp_ctx *pctx;
451 struct net_device *dev;
452 __be16 gtph_port;
453};
454
455static void gtp_push_header(struct sk_buff *skb, struct gtp_pktinfo *pktinfo)
456{
457 switch (pktinfo->pctx->gtp_version) {
458 case GTP_V0:
459 pktinfo->gtph_port = htons(GTP0_PORT);
460 gtp0_push_header(skb, pktinfo->pctx);
461 break;
462 case GTP_V1:
463 pktinfo->gtph_port = htons(GTP1U_PORT);
464 gtp1_push_header(skb, pktinfo->pctx);
465 break;
466 }
467}
468
469static inline void gtp_set_pktinfo_ipv4(struct gtp_pktinfo *pktinfo,
470 struct sock *sk, struct iphdr *iph,
471 struct pdp_ctx *pctx, struct rtable *rt,
472 struct flowi4 *fl4,
473 struct net_device *dev)
474{
475 pktinfo->sk = sk;
476 pktinfo->iph = iph;
477 pktinfo->pctx = pctx;
478 pktinfo->rt = rt;
479 pktinfo->fl4 = *fl4;
480 pktinfo->dev = dev;
481}
482
483static int gtp_build_skb_ip4(struct sk_buff *skb, struct net_device *dev,
484 struct gtp_pktinfo *pktinfo)
485{
486 struct gtp_dev *gtp = netdev_priv(dev);
487 struct pdp_ctx *pctx;
488 struct rtable *rt;
489 struct flowi4 fl4;
490 struct iphdr *iph;
491 __be16 df;
492 int mtu;
493
494 /* Read the IP destination address and resolve the PDP context.
495 * Prepend PDP header with TEI/TID from PDP ctx.
496 */
497 iph = ip_hdr(skb);
498 if (gtp->role == GTP_ROLE_SGSN)
499 pctx = ipv4_pdp_find(gtp, iph->saddr);
500 else
501 pctx = ipv4_pdp_find(gtp, iph->daddr);
502
503 if (!pctx) {
504 netdev_dbg(dev, "no PDP ctx found for %pI4, skip\n",
505 &iph->daddr);
506 return -ENOENT;
507 }
508 netdev_dbg(dev, "found PDP context %p\n", pctx);
509
510 rt = ip4_route_output_gtp(&fl4, pctx->sk, pctx->peer_addr_ip4.s_addr);
511 if (IS_ERR(rt)) {
512 netdev_dbg(dev, "no route to SSGN %pI4\n",
513 &pctx->peer_addr_ip4.s_addr);
514 dev->stats.tx_carrier_errors++;
515 goto err;
516 }
517
518 if (rt->dst.dev == dev) {
519 netdev_dbg(dev, "circular route to SSGN %pI4\n",
520 &pctx->peer_addr_ip4.s_addr);
521 dev->stats.collisions++;
522 goto err_rt;
523 }
524
525 skb_dst_drop(skb);
526
527 /* This is similar to tnl_update_pmtu(). */
528 df = iph->frag_off;
529 if (df) {
530 mtu = dst_mtu(&rt->dst) - dev->hard_header_len -
531 sizeof(struct iphdr) - sizeof(struct udphdr);
532 switch (pctx->gtp_version) {
533 case GTP_V0:
534 mtu -= sizeof(struct gtp0_header);
535 break;
536 case GTP_V1:
537 mtu -= sizeof(struct gtp1_header);
538 break;
539 }
540 } else {
541 mtu = dst_mtu(&rt->dst);
542 }
543
544 rt->dst.ops->update_pmtu(&rt->dst, NULL, skb, mtu);
545
546 if (!skb_is_gso(skb) && (iph->frag_off & htons(IP_DF)) &&
547 mtu < ntohs(iph->tot_len)) {
548 netdev_dbg(dev, "packet too big, fragmentation needed\n");
549 memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
550 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
551 htonl(mtu));
552 goto err_rt;
553 }
554
555 gtp_set_pktinfo_ipv4(pktinfo, pctx->sk, iph, pctx, rt, &fl4, dev);
556 gtp_push_header(skb, pktinfo);
557
558 return 0;
559err_rt:
560 ip_rt_put(rt);
561err:
562 return -EBADMSG;
563}
564
565static netdev_tx_t gtp_dev_xmit(struct sk_buff *skb, struct net_device *dev)
566{
567 unsigned int proto = ntohs(skb->protocol);
568 struct gtp_pktinfo pktinfo;
569 int err;
570
571 /* Ensure there is sufficient headroom. */
572 if (skb_cow_head(skb, dev->needed_headroom))
573 goto tx_err;
574
575 skb_reset_inner_headers(skb);
576
577 /* PDP context lookups in gtp_build_skb_*() need rcu read-side lock. */
578 rcu_read_lock();
579 switch (proto) {
580 case ETH_P_IP:
581 err = gtp_build_skb_ip4(skb, dev, &pktinfo);
582 break;
583 default:
584 err = -EOPNOTSUPP;
585 break;
586 }
587 rcu_read_unlock();
588
589 if (err < 0)
590 goto tx_err;
591
592 switch (proto) {
593 case ETH_P_IP:
594 netdev_dbg(pktinfo.dev, "gtp -> IP src: %pI4 dst: %pI4\n",
595 &pktinfo.iph->saddr, &pktinfo.iph->daddr);
596 udp_tunnel_xmit_skb(pktinfo.rt, pktinfo.sk, skb,
597 pktinfo.fl4.saddr, pktinfo.fl4.daddr,
598 pktinfo.iph->tos,
599 ip4_dst_hoplimit(&pktinfo.rt->dst),
600 0,
601 pktinfo.gtph_port, pktinfo.gtph_port,
602 true, false);
603 break;
604 }
605
606 return NETDEV_TX_OK;
607tx_err:
608 dev->stats.tx_errors++;
609 dev_kfree_skb(skb);
610 return NETDEV_TX_OK;
611}
612
613static const struct net_device_ops gtp_netdev_ops = {
614 .ndo_init = gtp_dev_init,
615 .ndo_uninit = gtp_dev_uninit,
616 .ndo_start_xmit = gtp_dev_xmit,
617 .ndo_get_stats64 = ip_tunnel_get_stats64,
618};
619
620static void gtp_link_setup(struct net_device *dev)
621{
622 dev->netdev_ops = >p_netdev_ops;
623 dev->needs_free_netdev = true;
624
625 dev->hard_header_len = 0;
626 dev->addr_len = 0;
627
628 /* Zero header length. */
629 dev->type = ARPHRD_NONE;
630 dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
631
632 dev->priv_flags |= IFF_NO_QUEUE;
633 dev->features |= NETIF_F_LLTX;
634 netif_keep_dst(dev);
635
636 /* Assume largest header, ie. GTPv0. */
637 dev->needed_headroom = LL_MAX_HEADER +
638 sizeof(struct iphdr) +
639 sizeof(struct udphdr) +
640 sizeof(struct gtp0_header);
641}
642
643static int gtp_hashtable_new(struct gtp_dev *gtp, int hsize);
644static void gtp_hashtable_free(struct gtp_dev *gtp);
645static int gtp_encap_enable(struct gtp_dev *gtp, struct nlattr *data[]);
646
647static int gtp_newlink(struct net *src_net, struct net_device *dev,
648 struct nlattr *tb[], struct nlattr *data[],
649 struct netlink_ext_ack *extack)
650{
651 struct gtp_dev *gtp;
652 struct gtp_net *gn;
653 int hashsize, err;
654
655 if (!data[IFLA_GTP_FD0] && !data[IFLA_GTP_FD1])
656 return -EINVAL;
657
658 gtp = netdev_priv(dev);
659
660 err = gtp_encap_enable(gtp, data);
661 if (err < 0)
662 return err;
663
664 if (!data[IFLA_GTP_PDP_HASHSIZE])
665 hashsize = 1024;
666 else
667 hashsize = nla_get_u32(data[IFLA_GTP_PDP_HASHSIZE]);
668
669 err = gtp_hashtable_new(gtp, hashsize);
670 if (err < 0)
671 goto out_encap;
672
673 err = register_netdevice(dev);
674 if (err < 0) {
675 netdev_dbg(dev, "failed to register new netdev %d\n", err);
676 goto out_hashtable;
677 }
678
679 gn = net_generic(dev_net(dev), gtp_net_id);
680 list_add_rcu(>p->list, &gn->gtp_dev_list);
681
682 netdev_dbg(dev, "registered new GTP interface\n");
683
684 return 0;
685
686out_hashtable:
687 gtp_hashtable_free(gtp);
688out_encap:
689 gtp_encap_disable(gtp);
690 return err;
691}
692
693static void gtp_dellink(struct net_device *dev, struct list_head *head)
694{
695 struct gtp_dev *gtp = netdev_priv(dev);
696
697 gtp_hashtable_free(gtp);
698 list_del_rcu(>p->list);
699 unregister_netdevice_queue(dev, head);
700}
701
702static const struct nla_policy gtp_policy[IFLA_GTP_MAX + 1] = {
703 [IFLA_GTP_FD0] = { .type = NLA_U32 },
704 [IFLA_GTP_FD1] = { .type = NLA_U32 },
705 [IFLA_GTP_PDP_HASHSIZE] = { .type = NLA_U32 },
706 [IFLA_GTP_ROLE] = { .type = NLA_U32 },
707};
708
709static int gtp_validate(struct nlattr *tb[], struct nlattr *data[],
710 struct netlink_ext_ack *extack)
711{
712 if (!data)
713 return -EINVAL;
714
715 return 0;
716}
717
718static size_t gtp_get_size(const struct net_device *dev)
719{
720 return nla_total_size(sizeof(__u32)); /* IFLA_GTP_PDP_HASHSIZE */
721}
722
723static int gtp_fill_info(struct sk_buff *skb, const struct net_device *dev)
724{
725 struct gtp_dev *gtp = netdev_priv(dev);
726
727 if (nla_put_u32(skb, IFLA_GTP_PDP_HASHSIZE, gtp->hash_size))
728 goto nla_put_failure;
729
730 return 0;
731
732nla_put_failure:
733 return -EMSGSIZE;
734}
735
736static struct rtnl_link_ops gtp_link_ops __read_mostly = {
737 .kind = "gtp",
738 .maxtype = IFLA_GTP_MAX,
739 .policy = gtp_policy,
740 .priv_size = sizeof(struct gtp_dev),
741 .setup = gtp_link_setup,
742 .validate = gtp_validate,
743 .newlink = gtp_newlink,
744 .dellink = gtp_dellink,
745 .get_size = gtp_get_size,
746 .fill_info = gtp_fill_info,
747};
748
749static int gtp_hashtable_new(struct gtp_dev *gtp, int hsize)
750{
751 int i;
752
753 gtp->addr_hash = kmalloc_array(hsize, sizeof(struct hlist_head),
754 GFP_KERNEL);
755 if (gtp->addr_hash == NULL)
756 return -ENOMEM;
757
758 gtp->tid_hash = kmalloc_array(hsize, sizeof(struct hlist_head),
759 GFP_KERNEL);
760 if (gtp->tid_hash == NULL)
761 goto err1;
762
763 gtp->hash_size = hsize;
764
765 for (i = 0; i < hsize; i++) {
766 INIT_HLIST_HEAD(>p->addr_hash[i]);
767 INIT_HLIST_HEAD(>p->tid_hash[i]);
768 }
769 return 0;
770err1:
771 kfree(gtp->addr_hash);
772 return -ENOMEM;
773}
774
775static void gtp_hashtable_free(struct gtp_dev *gtp)
776{
777 struct pdp_ctx *pctx;
778 int i;
779
780 for (i = 0; i < gtp->hash_size; i++)
781 hlist_for_each_entry_rcu(pctx, >p->tid_hash[i], hlist_tid)
782 pdp_context_delete(pctx);
783
784 synchronize_rcu();
785 kfree(gtp->addr_hash);
786 kfree(gtp->tid_hash);
787}
788
789static struct sock *gtp_encap_enable_socket(int fd, int type,
790 struct gtp_dev *gtp)
791{
792 struct udp_tunnel_sock_cfg tuncfg = {NULL};
793 struct socket *sock;
794 struct sock *sk;
795 int err;
796
797 pr_debug("enable gtp on %d, %d\n", fd, type);
798
799 sock = sockfd_lookup(fd, &err);
800 if (!sock) {
801 pr_debug("gtp socket fd=%d not found\n", fd);
802 return NULL;
803 }
804
805 if (sock->sk->sk_protocol != IPPROTO_UDP) {
806 pr_debug("socket fd=%d not UDP\n", fd);
807 sk = ERR_PTR(-EINVAL);
808 goto out_sock;
809 }
810
811 lock_sock(sock->sk);
812 if (sock->sk->sk_user_data) {
813 sk = ERR_PTR(-EBUSY);
814 goto out_sock;
815 }
816
817 sk = sock->sk;
818 sock_hold(sk);
819
820 tuncfg.sk_user_data = gtp;
821 tuncfg.encap_type = type;
822 tuncfg.encap_rcv = gtp_encap_recv;
823 tuncfg.encap_destroy = gtp_encap_destroy;
824
825 setup_udp_tunnel_sock(sock_net(sock->sk), sock, &tuncfg);
826
827out_sock:
828 release_sock(sock->sk);
829 sockfd_put(sock);
830 return sk;
831}
832
833static int gtp_encap_enable(struct gtp_dev *gtp, struct nlattr *data[])
834{
835 struct sock *sk1u = NULL;
836 struct sock *sk0 = NULL;
837 unsigned int role = GTP_ROLE_GGSN;
838
839 if (data[IFLA_GTP_FD0]) {
840 u32 fd0 = nla_get_u32(data[IFLA_GTP_FD0]);
841
842 sk0 = gtp_encap_enable_socket(fd0, UDP_ENCAP_GTP0, gtp);
843 if (IS_ERR(sk0))
844 return PTR_ERR(sk0);
845 }
846
847 if (data[IFLA_GTP_FD1]) {
848 u32 fd1 = nla_get_u32(data[IFLA_GTP_FD1]);
849
850 sk1u = gtp_encap_enable_socket(fd1, UDP_ENCAP_GTP1U, gtp);
851 if (IS_ERR(sk1u)) {
852 if (sk0)
853 gtp_encap_disable_sock(sk0);
854 return PTR_ERR(sk1u);
855 }
856 }
857
858 if (data[IFLA_GTP_ROLE]) {
859 role = nla_get_u32(data[IFLA_GTP_ROLE]);
860 if (role > GTP_ROLE_SGSN) {
861 if (sk0)
862 gtp_encap_disable_sock(sk0);
863 if (sk1u)
864 gtp_encap_disable_sock(sk1u);
865 return -EINVAL;
866 }
867 }
868
869 gtp->sk0 = sk0;
870 gtp->sk1u = sk1u;
871 gtp->role = role;
872
873 return 0;
874}
875
876static struct gtp_dev *gtp_find_dev(struct net *src_net, struct nlattr *nla[])
877{
878 struct gtp_dev *gtp = NULL;
879 struct net_device *dev;
880 struct net *net;
881
882 /* Examine the link attributes and figure out which network namespace
883 * we are talking about.
884 */
885 if (nla[GTPA_NET_NS_FD])
886 net = get_net_ns_by_fd(nla_get_u32(nla[GTPA_NET_NS_FD]));
887 else
888 net = get_net(src_net);
889
890 if (IS_ERR(net))
891 return NULL;
892
893 /* Check if there's an existing gtpX device to configure */
894 dev = dev_get_by_index_rcu(net, nla_get_u32(nla[GTPA_LINK]));
895 if (dev && dev->netdev_ops == >p_netdev_ops)
896 gtp = netdev_priv(dev);
897
898 put_net(net);
899 return gtp;
900}
901
902static void ipv4_pdp_fill(struct pdp_ctx *pctx, struct genl_info *info)
903{
904 pctx->gtp_version = nla_get_u32(info->attrs[GTPA_VERSION]);
905 pctx->af = AF_INET;
906 pctx->peer_addr_ip4.s_addr =
907 nla_get_be32(info->attrs[GTPA_PEER_ADDRESS]);
908 pctx->ms_addr_ip4.s_addr =
909 nla_get_be32(info->attrs[GTPA_MS_ADDRESS]);
910
911 switch (pctx->gtp_version) {
912 case GTP_V0:
913 /* According to TS 09.60, sections 7.5.1 and 7.5.2, the flow
914 * label needs to be the same for uplink and downlink packets,
915 * so let's annotate this.
916 */
917 pctx->u.v0.tid = nla_get_u64(info->attrs[GTPA_TID]);
918 pctx->u.v0.flow = nla_get_u16(info->attrs[GTPA_FLOW]);
919 break;
920 case GTP_V1:
921 pctx->u.v1.i_tei = nla_get_u32(info->attrs[GTPA_I_TEI]);
922 pctx->u.v1.o_tei = nla_get_u32(info->attrs[GTPA_O_TEI]);
923 break;
924 default:
925 break;
926 }
927}
928
929static int ipv4_pdp_add(struct gtp_dev *gtp, struct sock *sk,
930 struct genl_info *info)
931{
932 struct net_device *dev = gtp->dev;
933 u32 hash_ms, hash_tid = 0;
934 struct pdp_ctx *pctx;
935 bool found = false;
936 __be32 ms_addr;
937
938 ms_addr = nla_get_be32(info->attrs[GTPA_MS_ADDRESS]);
939 hash_ms = ipv4_hashfn(ms_addr) % gtp->hash_size;
940
941 hlist_for_each_entry_rcu(pctx, >p->addr_hash[hash_ms], hlist_addr) {
942 if (pctx->ms_addr_ip4.s_addr == ms_addr) {
943 found = true;
944 break;
945 }
946 }
947
948 if (found) {
949 if (info->nlhdr->nlmsg_flags & NLM_F_EXCL)
950 return -EEXIST;
951 if (info->nlhdr->nlmsg_flags & NLM_F_REPLACE)
952 return -EOPNOTSUPP;
953
954 ipv4_pdp_fill(pctx, info);
955
956 if (pctx->gtp_version == GTP_V0)
957 netdev_dbg(dev, "GTPv0-U: update tunnel id = %llx (pdp %p)\n",
958 pctx->u.v0.tid, pctx);
959 else if (pctx->gtp_version == GTP_V1)
960 netdev_dbg(dev, "GTPv1-U: update tunnel id = %x/%x (pdp %p)\n",
961 pctx->u.v1.i_tei, pctx->u.v1.o_tei, pctx);
962
963 return 0;
964
965 }
966
967 pctx = kmalloc(sizeof(*pctx), GFP_ATOMIC);
968 if (pctx == NULL)
969 return -ENOMEM;
970
971 sock_hold(sk);
972 pctx->sk = sk;
973 pctx->dev = gtp->dev;
974 ipv4_pdp_fill(pctx, info);
975 atomic_set(&pctx->tx_seq, 0);
976
977 switch (pctx->gtp_version) {
978 case GTP_V0:
979 /* TS 09.60: "The flow label identifies unambiguously a GTP
980 * flow.". We use the tid for this instead, I cannot find a
981 * situation in which this doesn't unambiguosly identify the
982 * PDP context.
983 */
984 hash_tid = gtp0_hashfn(pctx->u.v0.tid) % gtp->hash_size;
985 break;
986 case GTP_V1:
987 hash_tid = gtp1u_hashfn(pctx->u.v1.i_tei) % gtp->hash_size;
988 break;
989 }
990
991 hlist_add_head_rcu(&pctx->hlist_addr, >p->addr_hash[hash_ms]);
992 hlist_add_head_rcu(&pctx->hlist_tid, >p->tid_hash[hash_tid]);
993
994 switch (pctx->gtp_version) {
995 case GTP_V0:
996 netdev_dbg(dev, "GTPv0-U: new PDP ctx id=%llx ssgn=%pI4 ms=%pI4 (pdp=%p)\n",
997 pctx->u.v0.tid, &pctx->peer_addr_ip4,
998 &pctx->ms_addr_ip4, pctx);
999 break;
1000 case GTP_V1:
1001 netdev_dbg(dev, "GTPv1-U: new PDP ctx id=%x/%x ssgn=%pI4 ms=%pI4 (pdp=%p)\n",
1002 pctx->u.v1.i_tei, pctx->u.v1.o_tei,
1003 &pctx->peer_addr_ip4, &pctx->ms_addr_ip4, pctx);
1004 break;
1005 }
1006
1007 return 0;
1008}
1009
1010static void pdp_context_free(struct rcu_head *head)
1011{
1012 struct pdp_ctx *pctx = container_of(head, struct pdp_ctx, rcu_head);
1013
1014 sock_put(pctx->sk);
1015 kfree(pctx);
1016}
1017
1018static void pdp_context_delete(struct pdp_ctx *pctx)
1019{
1020 hlist_del_rcu(&pctx->hlist_tid);
1021 hlist_del_rcu(&pctx->hlist_addr);
1022 call_rcu(&pctx->rcu_head, pdp_context_free);
1023}
1024
1025static int gtp_genl_new_pdp(struct sk_buff *skb, struct genl_info *info)
1026{
1027 unsigned int version;
1028 struct gtp_dev *gtp;
1029 struct sock *sk;
1030 int err;
1031
1032 if (!info->attrs[GTPA_VERSION] ||
1033 !info->attrs[GTPA_LINK] ||
1034 !info->attrs[GTPA_PEER_ADDRESS] ||
1035 !info->attrs[GTPA_MS_ADDRESS])
1036 return -EINVAL;
1037
1038 version = nla_get_u32(info->attrs[GTPA_VERSION]);
1039
1040 switch (version) {
1041 case GTP_V0:
1042 if (!info->attrs[GTPA_TID] ||
1043 !info->attrs[GTPA_FLOW])
1044 return -EINVAL;
1045 break;
1046 case GTP_V1:
1047 if (!info->attrs[GTPA_I_TEI] ||
1048 !info->attrs[GTPA_O_TEI])
1049 return -EINVAL;
1050 break;
1051
1052 default:
1053 return -EINVAL;
1054 }
1055
1056 rtnl_lock();
1057 rcu_read_lock();
1058
1059 gtp = gtp_find_dev(sock_net(skb->sk), info->attrs);
1060 if (!gtp) {
1061 err = -ENODEV;
1062 goto out_unlock;
1063 }
1064
1065 if (version == GTP_V0)
1066 sk = gtp->sk0;
1067 else if (version == GTP_V1)
1068 sk = gtp->sk1u;
1069 else
1070 sk = NULL;
1071
1072 if (!sk) {
1073 err = -ENODEV;
1074 goto out_unlock;
1075 }
1076
1077 err = ipv4_pdp_add(gtp, sk, info);
1078
1079out_unlock:
1080 rcu_read_unlock();
1081 rtnl_unlock();
1082 return err;
1083}
1084
1085static struct pdp_ctx *gtp_find_pdp_by_link(struct net *net,
1086 struct nlattr *nla[])
1087{
1088 struct gtp_dev *gtp;
1089
1090 gtp = gtp_find_dev(net, nla);
1091 if (!gtp)
1092 return ERR_PTR(-ENODEV);
1093
1094 if (nla[GTPA_MS_ADDRESS]) {
1095 __be32 ip = nla_get_be32(nla[GTPA_MS_ADDRESS]);
1096
1097 return ipv4_pdp_find(gtp, ip);
1098 } else if (nla[GTPA_VERSION]) {
1099 u32 gtp_version = nla_get_u32(nla[GTPA_VERSION]);
1100
1101 if (gtp_version == GTP_V0 && nla[GTPA_TID])
1102 return gtp0_pdp_find(gtp, nla_get_u64(nla[GTPA_TID]));
1103 else if (gtp_version == GTP_V1 && nla[GTPA_I_TEI])
1104 return gtp1_pdp_find(gtp, nla_get_u32(nla[GTPA_I_TEI]));
1105 }
1106
1107 return ERR_PTR(-EINVAL);
1108}
1109
1110static struct pdp_ctx *gtp_find_pdp(struct net *net, struct nlattr *nla[])
1111{
1112 struct pdp_ctx *pctx;
1113
1114 if (nla[GTPA_LINK])
1115 pctx = gtp_find_pdp_by_link(net, nla);
1116 else
1117 pctx = ERR_PTR(-EINVAL);
1118
1119 if (!pctx)
1120 pctx = ERR_PTR(-ENOENT);
1121
1122 return pctx;
1123}
1124
1125static int gtp_genl_del_pdp(struct sk_buff *skb, struct genl_info *info)
1126{
1127 struct pdp_ctx *pctx;
1128 int err = 0;
1129
1130 if (!info->attrs[GTPA_VERSION])
1131 return -EINVAL;
1132
1133 rcu_read_lock();
1134
1135 pctx = gtp_find_pdp(sock_net(skb->sk), info->attrs);
1136 if (IS_ERR(pctx)) {
1137 err = PTR_ERR(pctx);
1138 goto out_unlock;
1139 }
1140
1141 if (pctx->gtp_version == GTP_V0)
1142 netdev_dbg(pctx->dev, "GTPv0-U: deleting tunnel id = %llx (pdp %p)\n",
1143 pctx->u.v0.tid, pctx);
1144 else if (pctx->gtp_version == GTP_V1)
1145 netdev_dbg(pctx->dev, "GTPv1-U: deleting tunnel id = %x/%x (pdp %p)\n",
1146 pctx->u.v1.i_tei, pctx->u.v1.o_tei, pctx);
1147
1148 pdp_context_delete(pctx);
1149
1150out_unlock:
1151 rcu_read_unlock();
1152 return err;
1153}
1154
1155static struct genl_family gtp_genl_family;
1156
1157static int gtp_genl_fill_info(struct sk_buff *skb, u32 snd_portid, u32 snd_seq,
1158 u32 type, struct pdp_ctx *pctx)
1159{
1160 void *genlh;
1161
1162 genlh = genlmsg_put(skb, snd_portid, snd_seq, >p_genl_family, 0,
1163 type);
1164 if (genlh == NULL)
1165 goto nlmsg_failure;
1166
1167 if (nla_put_u32(skb, GTPA_VERSION, pctx->gtp_version) ||
1168 nla_put_be32(skb, GTPA_PEER_ADDRESS, pctx->peer_addr_ip4.s_addr) ||
1169 nla_put_be32(skb, GTPA_MS_ADDRESS, pctx->ms_addr_ip4.s_addr))
1170 goto nla_put_failure;
1171
1172 switch (pctx->gtp_version) {
1173 case GTP_V0:
1174 if (nla_put_u64_64bit(skb, GTPA_TID, pctx->u.v0.tid, GTPA_PAD) ||
1175 nla_put_u16(skb, GTPA_FLOW, pctx->u.v0.flow))
1176 goto nla_put_failure;
1177 break;
1178 case GTP_V1:
1179 if (nla_put_u32(skb, GTPA_I_TEI, pctx->u.v1.i_tei) ||
1180 nla_put_u32(skb, GTPA_O_TEI, pctx->u.v1.o_tei))
1181 goto nla_put_failure;
1182 break;
1183 }
1184 genlmsg_end(skb, genlh);
1185 return 0;
1186
1187nlmsg_failure:
1188nla_put_failure:
1189 genlmsg_cancel(skb, genlh);
1190 return -EMSGSIZE;
1191}
1192
1193static int gtp_genl_get_pdp(struct sk_buff *skb, struct genl_info *info)
1194{
1195 struct pdp_ctx *pctx = NULL;
1196 struct sk_buff *skb2;
1197 int err;
1198
1199 if (!info->attrs[GTPA_VERSION])
1200 return -EINVAL;
1201
1202 rcu_read_lock();
1203
1204 pctx = gtp_find_pdp(sock_net(skb->sk), info->attrs);
1205 if (IS_ERR(pctx)) {
1206 err = PTR_ERR(pctx);
1207 goto err_unlock;
1208 }
1209
1210 skb2 = genlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC);
1211 if (skb2 == NULL) {
1212 err = -ENOMEM;
1213 goto err_unlock;
1214 }
1215
1216 err = gtp_genl_fill_info(skb2, NETLINK_CB(skb).portid,
1217 info->snd_seq, info->nlhdr->nlmsg_type, pctx);
1218 if (err < 0)
1219 goto err_unlock_free;
1220
1221 rcu_read_unlock();
1222 return genlmsg_unicast(genl_info_net(info), skb2, info->snd_portid);
1223
1224err_unlock_free:
1225 kfree_skb(skb2);
1226err_unlock:
1227 rcu_read_unlock();
1228 return err;
1229}
1230
1231static int gtp_genl_dump_pdp(struct sk_buff *skb,
1232 struct netlink_callback *cb)
1233{
1234 struct gtp_dev *last_gtp = (struct gtp_dev *)cb->args[2], *gtp;
1235 struct net *net = sock_net(skb->sk);
1236 struct gtp_net *gn = net_generic(net, gtp_net_id);
1237 unsigned long tid = cb->args[1];
1238 int i, k = cb->args[0], ret;
1239 struct pdp_ctx *pctx;
1240
1241 if (cb->args[4])
1242 return 0;
1243
1244 list_for_each_entry_rcu(gtp, &gn->gtp_dev_list, list) {
1245 if (last_gtp && last_gtp != gtp)
1246 continue;
1247 else
1248 last_gtp = NULL;
1249
1250 for (i = k; i < gtp->hash_size; i++) {
1251 hlist_for_each_entry_rcu(pctx, >p->tid_hash[i], hlist_tid) {
1252 if (tid && tid != pctx->u.tid)
1253 continue;
1254 else
1255 tid = 0;
1256
1257 ret = gtp_genl_fill_info(skb,
1258 NETLINK_CB(cb->skb).portid,
1259 cb->nlh->nlmsg_seq,
1260 cb->nlh->nlmsg_type, pctx);
1261 if (ret < 0) {
1262 cb->args[0] = i;
1263 cb->args[1] = pctx->u.tid;
1264 cb->args[2] = (unsigned long)gtp;
1265 goto out;
1266 }
1267 }
1268 }
1269 }
1270 cb->args[4] = 1;
1271out:
1272 return skb->len;
1273}
1274
1275static const struct nla_policy gtp_genl_policy[GTPA_MAX + 1] = {
1276 [GTPA_LINK] = { .type = NLA_U32, },
1277 [GTPA_VERSION] = { .type = NLA_U32, },
1278 [GTPA_TID] = { .type = NLA_U64, },
1279 [GTPA_PEER_ADDRESS] = { .type = NLA_U32, },
1280 [GTPA_MS_ADDRESS] = { .type = NLA_U32, },
1281 [GTPA_FLOW] = { .type = NLA_U16, },
1282 [GTPA_NET_NS_FD] = { .type = NLA_U32, },
1283 [GTPA_I_TEI] = { .type = NLA_U32, },
1284 [GTPA_O_TEI] = { .type = NLA_U32, },
1285};
1286
1287static const struct genl_ops gtp_genl_ops[] = {
1288 {
1289 .cmd = GTP_CMD_NEWPDP,
1290 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
1291 .doit = gtp_genl_new_pdp,
1292 .flags = GENL_ADMIN_PERM,
1293 },
1294 {
1295 .cmd = GTP_CMD_DELPDP,
1296 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
1297 .doit = gtp_genl_del_pdp,
1298 .flags = GENL_ADMIN_PERM,
1299 },
1300 {
1301 .cmd = GTP_CMD_GETPDP,
1302 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
1303 .doit = gtp_genl_get_pdp,
1304 .dumpit = gtp_genl_dump_pdp,
1305 .flags = GENL_ADMIN_PERM,
1306 },
1307};
1308
1309static struct genl_family gtp_genl_family __ro_after_init = {
1310 .name = "gtp",
1311 .version = 0,
1312 .hdrsize = 0,
1313 .maxattr = GTPA_MAX,
1314 .policy = gtp_genl_policy,
1315 .netnsok = true,
1316 .module = THIS_MODULE,
1317 .ops = gtp_genl_ops,
1318 .n_ops = ARRAY_SIZE(gtp_genl_ops),
1319};
1320
1321static int __net_init gtp_net_init(struct net *net)
1322{
1323 struct gtp_net *gn = net_generic(net, gtp_net_id);
1324
1325 INIT_LIST_HEAD(&gn->gtp_dev_list);
1326 return 0;
1327}
1328
1329static void __net_exit gtp_net_exit(struct net *net)
1330{
1331 struct gtp_net *gn = net_generic(net, gtp_net_id);
1332 struct gtp_dev *gtp;
1333 LIST_HEAD(list);
1334
1335 rtnl_lock();
1336 list_for_each_entry(gtp, &gn->gtp_dev_list, list)
1337 gtp_dellink(gtp->dev, &list);
1338
1339 unregister_netdevice_many(&list);
1340 rtnl_unlock();
1341}
1342
1343static struct pernet_operations gtp_net_ops = {
1344 .init = gtp_net_init,
1345 .exit = gtp_net_exit,
1346 .id = >p_net_id,
1347 .size = sizeof(struct gtp_net),
1348};
1349
1350static int __init gtp_init(void)
1351{
1352 int err;
1353
1354 get_random_bytes(>p_h_initval, sizeof(gtp_h_initval));
1355
1356 err = rtnl_link_register(>p_link_ops);
1357 if (err < 0)
1358 goto error_out;
1359
1360 err = genl_register_family(>p_genl_family);
1361 if (err < 0)
1362 goto unreg_rtnl_link;
1363
1364 err = register_pernet_subsys(>p_net_ops);
1365 if (err < 0)
1366 goto unreg_genl_family;
1367
1368 pr_info("GTP module loaded (pdp ctx size %zd bytes)\n",
1369 sizeof(struct pdp_ctx));
1370 return 0;
1371
1372unreg_genl_family:
1373 genl_unregister_family(>p_genl_family);
1374unreg_rtnl_link:
1375 rtnl_link_unregister(>p_link_ops);
1376error_out:
1377 pr_err("error loading GTP module loaded\n");
1378 return err;
1379}
1380late_initcall(gtp_init);
1381
1382static void __exit gtp_fini(void)
1383{
1384 genl_unregister_family(>p_genl_family);
1385 rtnl_link_unregister(>p_link_ops);
1386 unregister_pernet_subsys(>p_net_ops);
1387
1388 pr_info("GTP module unloaded\n");
1389}
1390module_exit(gtp_fini);
1391
1392MODULE_LICENSE("GPL");
1393MODULE_AUTHOR("Harald Welte <hwelte@sysmocom.de>");
1394MODULE_DESCRIPTION("Interface driver for GTP encapsulated traffic");
1395MODULE_ALIAS_RTNL_LINK("gtp");
1396MODULE_ALIAS_GENL_FAMILY("gtp");
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>
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. */
40struct 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. */
66struct gtp_dev {
67 struct list_head list;
68
69 struct socket *sock0;
70 struct socket *sock1u;
71
72 struct net_device *dev;
73
74 unsigned int hash_size;
75 struct hlist_head *tid_hash;
76 struct hlist_head *addr_hash;
77};
78
79static unsigned int gtp_net_id __read_mostly;
80
81struct gtp_net {
82 struct list_head gtp_dev_list;
83};
84
85static u32 gtp_h_initval;
86
87static inline u32 gtp0_hashfn(u64 tid)
88{
89 u32 *tid32 = (u32 *) &tid;
90 return jhash_2words(tid32[0], tid32[1], gtp_h_initval);
91}
92
93static inline u32 gtp1u_hashfn(u32 tid)
94{
95 return jhash_1word(tid, gtp_h_initval);
96}
97
98static inline u32 ipv4_hashfn(__be32 ip)
99{
100 return jhash_1word((__force u32)ip, gtp_h_initval);
101}
102
103/* Resolve a PDP context structure based on the 64bit TID. */
104static struct pdp_ctx *gtp0_pdp_find(struct gtp_dev *gtp, u64 tid)
105{
106 struct hlist_head *head;
107 struct pdp_ctx *pdp;
108
109 head = >p->tid_hash[gtp0_hashfn(tid) % gtp->hash_size];
110
111 hlist_for_each_entry_rcu(pdp, head, hlist_tid) {
112 if (pdp->gtp_version == GTP_V0 &&
113 pdp->u.v0.tid == tid)
114 return pdp;
115 }
116 return NULL;
117}
118
119/* Resolve a PDP context structure based on the 32bit TEI. */
120static struct pdp_ctx *gtp1_pdp_find(struct gtp_dev *gtp, u32 tid)
121{
122 struct hlist_head *head;
123 struct pdp_ctx *pdp;
124
125 head = >p->tid_hash[gtp1u_hashfn(tid) % gtp->hash_size];
126
127 hlist_for_each_entry_rcu(pdp, head, hlist_tid) {
128 if (pdp->gtp_version == GTP_V1 &&
129 pdp->u.v1.i_tei == tid)
130 return pdp;
131 }
132 return NULL;
133}
134
135/* Resolve a PDP context based on IPv4 address of MS. */
136static struct pdp_ctx *ipv4_pdp_find(struct gtp_dev *gtp, __be32 ms_addr)
137{
138 struct hlist_head *head;
139 struct pdp_ctx *pdp;
140
141 head = >p->addr_hash[ipv4_hashfn(ms_addr) % gtp->hash_size];
142
143 hlist_for_each_entry_rcu(pdp, head, hlist_addr) {
144 if (pdp->af == AF_INET &&
145 pdp->ms_addr_ip4.s_addr == ms_addr)
146 return pdp;
147 }
148
149 return NULL;
150}
151
152static bool gtp_check_src_ms_ipv4(struct sk_buff *skb, struct pdp_ctx *pctx,
153 unsigned int hdrlen)
154{
155 struct iphdr *iph;
156
157 if (!pskb_may_pull(skb, hdrlen + sizeof(struct iphdr)))
158 return false;
159
160 iph = (struct iphdr *)(skb->data + hdrlen);
161
162 return iph->saddr == pctx->ms_addr_ip4.s_addr;
163}
164
165/* Check if the inner IP source address in this packet is assigned to any
166 * existing mobile subscriber.
167 */
168static bool gtp_check_src_ms(struct sk_buff *skb, struct pdp_ctx *pctx,
169 unsigned int hdrlen)
170{
171 switch (ntohs(skb->protocol)) {
172 case ETH_P_IP:
173 return gtp_check_src_ms_ipv4(skb, pctx, hdrlen);
174 }
175 return false;
176}
177
178/* 1 means pass up to the stack, -1 means drop and 0 means decapsulated. */
179static int gtp0_udp_encap_recv(struct gtp_dev *gtp, struct sk_buff *skb,
180 bool xnet)
181{
182 unsigned int hdrlen = sizeof(struct udphdr) +
183 sizeof(struct gtp0_header);
184 struct gtp0_header *gtp0;
185 struct pdp_ctx *pctx;
186 int ret = 0;
187
188 if (!pskb_may_pull(skb, hdrlen))
189 return -1;
190
191 gtp0 = (struct gtp0_header *)(skb->data + sizeof(struct udphdr));
192
193 if ((gtp0->flags >> 5) != GTP_V0)
194 return 1;
195
196 if (gtp0->type != GTP_TPDU)
197 return 1;
198
199 rcu_read_lock();
200 pctx = gtp0_pdp_find(gtp, be64_to_cpu(gtp0->tid));
201 if (!pctx) {
202 netdev_dbg(gtp->dev, "No PDP ctx to decap skb=%p\n", skb);
203 ret = -1;
204 goto out_rcu;
205 }
206
207 if (!gtp_check_src_ms(skb, pctx, hdrlen)) {
208 netdev_dbg(gtp->dev, "No PDP ctx for this MS\n");
209 ret = -1;
210 goto out_rcu;
211 }
212 rcu_read_unlock();
213
214 /* Get rid of the GTP + UDP headers. */
215 return iptunnel_pull_header(skb, hdrlen, skb->protocol, xnet);
216out_rcu:
217 rcu_read_unlock();
218 return ret;
219}
220
221static int gtp1u_udp_encap_recv(struct gtp_dev *gtp, struct sk_buff *skb,
222 bool xnet)
223{
224 unsigned int hdrlen = sizeof(struct udphdr) +
225 sizeof(struct gtp1_header);
226 struct gtp1_header *gtp1;
227 struct pdp_ctx *pctx;
228 int ret = 0;
229
230 if (!pskb_may_pull(skb, hdrlen))
231 return -1;
232
233 gtp1 = (struct gtp1_header *)(skb->data + sizeof(struct udphdr));
234
235 if ((gtp1->flags >> 5) != GTP_V1)
236 return 1;
237
238 if (gtp1->type != GTP_TPDU)
239 return 1;
240
241 /* From 29.060: "This field shall be present if and only if any one or
242 * more of the S, PN and E flags are set.".
243 *
244 * If any of the bit is set, then the remaining ones also have to be
245 * set.
246 */
247 if (gtp1->flags & GTP1_F_MASK)
248 hdrlen += 4;
249
250 /* Make sure the header is larger enough, including extensions. */
251 if (!pskb_may_pull(skb, hdrlen))
252 return -1;
253
254 gtp1 = (struct gtp1_header *)(skb->data + sizeof(struct udphdr));
255
256 rcu_read_lock();
257 pctx = gtp1_pdp_find(gtp, ntohl(gtp1->tid));
258 if (!pctx) {
259 netdev_dbg(gtp->dev, "No PDP ctx to decap skb=%p\n", skb);
260 ret = -1;
261 goto out_rcu;
262 }
263
264 if (!gtp_check_src_ms(skb, pctx, hdrlen)) {
265 netdev_dbg(gtp->dev, "No PDP ctx for this MS\n");
266 ret = -1;
267 goto out_rcu;
268 }
269 rcu_read_unlock();
270
271 /* Get rid of the GTP + UDP headers. */
272 return iptunnel_pull_header(skb, hdrlen, skb->protocol, xnet);
273out_rcu:
274 rcu_read_unlock();
275 return ret;
276}
277
278static void gtp_encap_disable(struct gtp_dev *gtp)
279{
280 if (gtp->sock0 && gtp->sock0->sk) {
281 udp_sk(gtp->sock0->sk)->encap_type = 0;
282 rcu_assign_sk_user_data(gtp->sock0->sk, NULL);
283 }
284 if (gtp->sock1u && gtp->sock1u->sk) {
285 udp_sk(gtp->sock1u->sk)->encap_type = 0;
286 rcu_assign_sk_user_data(gtp->sock1u->sk, NULL);
287 }
288
289 gtp->sock0 = NULL;
290 gtp->sock1u = NULL;
291}
292
293static void gtp_encap_destroy(struct sock *sk)
294{
295 struct gtp_dev *gtp;
296
297 gtp = rcu_dereference_sk_user_data(sk);
298 if (gtp)
299 gtp_encap_disable(gtp);
300}
301
302/* UDP encapsulation receive handler. See net/ipv4/udp.c.
303 * Return codes: 0: success, <0: error, >0: pass up to userspace UDP socket.
304 */
305static int gtp_encap_recv(struct sock *sk, struct sk_buff *skb)
306{
307 struct pcpu_sw_netstats *stats;
308 struct gtp_dev *gtp;
309 bool xnet;
310 int ret;
311
312 gtp = rcu_dereference_sk_user_data(sk);
313 if (!gtp)
314 return 1;
315
316 netdev_dbg(gtp->dev, "encap_recv sk=%p\n", sk);
317
318 xnet = !net_eq(sock_net(sk), dev_net(gtp->dev));
319
320 switch (udp_sk(sk)->encap_type) {
321 case UDP_ENCAP_GTP0:
322 netdev_dbg(gtp->dev, "received GTP0 packet\n");
323 ret = gtp0_udp_encap_recv(gtp, skb, xnet);
324 break;
325 case UDP_ENCAP_GTP1U:
326 netdev_dbg(gtp->dev, "received GTP1U packet\n");
327 ret = gtp1u_udp_encap_recv(gtp, skb, xnet);
328 break;
329 default:
330 ret = -1; /* Shouldn't happen. */
331 }
332
333 switch (ret) {
334 case 1:
335 netdev_dbg(gtp->dev, "pass up to the process\n");
336 return 1;
337 case 0:
338 netdev_dbg(gtp->dev, "forwarding packet from GGSN to uplink\n");
339 break;
340 case -1:
341 netdev_dbg(gtp->dev, "GTP packet has been dropped\n");
342 kfree_skb(skb);
343 return 0;
344 }
345
346 /* Now that the UDP and the GTP header have been removed, set up the
347 * new network header. This is required by the upper layer to
348 * calculate the transport header.
349 */
350 skb_reset_network_header(skb);
351
352 skb->dev = gtp->dev;
353
354 stats = this_cpu_ptr(gtp->dev->tstats);
355 u64_stats_update_begin(&stats->syncp);
356 stats->rx_packets++;
357 stats->rx_bytes += skb->len;
358 u64_stats_update_end(&stats->syncp);
359
360 netif_rx(skb);
361
362 return 0;
363}
364
365static int gtp_dev_init(struct net_device *dev)
366{
367 struct gtp_dev *gtp = netdev_priv(dev);
368
369 gtp->dev = dev;
370
371 dev->tstats = alloc_percpu(struct pcpu_sw_netstats);
372 if (!dev->tstats)
373 return -ENOMEM;
374
375 return 0;
376}
377
378static void gtp_dev_uninit(struct net_device *dev)
379{
380 struct gtp_dev *gtp = netdev_priv(dev);
381
382 gtp_encap_disable(gtp);
383 free_percpu(dev->tstats);
384}
385
386static struct rtable *ip4_route_output_gtp(struct net *net, struct flowi4 *fl4,
387 const struct sock *sk, __be32 daddr)
388{
389 memset(fl4, 0, sizeof(*fl4));
390 fl4->flowi4_oif = sk->sk_bound_dev_if;
391 fl4->daddr = daddr;
392 fl4->saddr = inet_sk(sk)->inet_saddr;
393 fl4->flowi4_tos = RT_CONN_FLAGS(sk);
394 fl4->flowi4_proto = sk->sk_protocol;
395
396 return ip_route_output_key(net, fl4);
397}
398
399static inline void gtp0_push_header(struct sk_buff *skb, struct pdp_ctx *pctx)
400{
401 int payload_len = skb->len;
402 struct gtp0_header *gtp0;
403
404 gtp0 = (struct gtp0_header *) skb_push(skb, sizeof(*gtp0));
405
406 gtp0->flags = 0x1e; /* v0, GTP-non-prime. */
407 gtp0->type = GTP_TPDU;
408 gtp0->length = htons(payload_len);
409 gtp0->seq = htons((atomic_inc_return(&pctx->tx_seq) - 1) % 0xffff);
410 gtp0->flow = htons(pctx->u.v0.flow);
411 gtp0->number = 0xff;
412 gtp0->spare[0] = gtp0->spare[1] = gtp0->spare[2] = 0xff;
413 gtp0->tid = cpu_to_be64(pctx->u.v0.tid);
414}
415
416static inline void gtp1_push_header(struct sk_buff *skb, struct pdp_ctx *pctx)
417{
418 int payload_len = skb->len;
419 struct gtp1_header *gtp1;
420
421 gtp1 = (struct gtp1_header *) skb_push(skb, sizeof(*gtp1));
422
423 /* Bits 8 7 6 5 4 3 2 1
424 * +--+--+--+--+--+--+--+--+
425 * |version |PT| 0| E| S|PN|
426 * +--+--+--+--+--+--+--+--+
427 * 0 0 1 1 1 0 0 0
428 */
429 gtp1->flags = 0x30; /* v1, GTP-non-prime. */
430 gtp1->type = GTP_TPDU;
431 gtp1->length = htons(payload_len);
432 gtp1->tid = htonl(pctx->u.v1.o_tei);
433
434 /* TODO: Suppport for extension header, sequence number and N-PDU.
435 * Update the length field if any of them is available.
436 */
437}
438
439struct gtp_pktinfo {
440 struct sock *sk;
441 struct iphdr *iph;
442 struct flowi4 fl4;
443 struct rtable *rt;
444 struct pdp_ctx *pctx;
445 struct net_device *dev;
446 __be16 gtph_port;
447};
448
449static void gtp_push_header(struct sk_buff *skb, struct gtp_pktinfo *pktinfo)
450{
451 switch (pktinfo->pctx->gtp_version) {
452 case GTP_V0:
453 pktinfo->gtph_port = htons(GTP0_PORT);
454 gtp0_push_header(skb, pktinfo->pctx);
455 break;
456 case GTP_V1:
457 pktinfo->gtph_port = htons(GTP1U_PORT);
458 gtp1_push_header(skb, pktinfo->pctx);
459 break;
460 }
461}
462
463static inline void gtp_set_pktinfo_ipv4(struct gtp_pktinfo *pktinfo,
464 struct sock *sk, struct iphdr *iph,
465 struct pdp_ctx *pctx, struct rtable *rt,
466 struct flowi4 *fl4,
467 struct net_device *dev)
468{
469 pktinfo->sk = sk;
470 pktinfo->iph = iph;
471 pktinfo->pctx = pctx;
472 pktinfo->rt = rt;
473 pktinfo->fl4 = *fl4;
474 pktinfo->dev = dev;
475}
476
477static int gtp_build_skb_ip4(struct sk_buff *skb, struct net_device *dev,
478 struct gtp_pktinfo *pktinfo)
479{
480 struct gtp_dev *gtp = netdev_priv(dev);
481 struct pdp_ctx *pctx;
482 struct rtable *rt;
483 struct flowi4 fl4;
484 struct iphdr *iph;
485 struct sock *sk;
486 __be16 df;
487 int mtu;
488
489 /* Read the IP destination address and resolve the PDP context.
490 * Prepend PDP header with TEI/TID from PDP ctx.
491 */
492 iph = ip_hdr(skb);
493 pctx = ipv4_pdp_find(gtp, iph->daddr);
494 if (!pctx) {
495 netdev_dbg(dev, "no PDP ctx found for %pI4, skip\n",
496 &iph->daddr);
497 return -ENOENT;
498 }
499 netdev_dbg(dev, "found PDP context %p\n", pctx);
500
501 switch (pctx->gtp_version) {
502 case GTP_V0:
503 if (gtp->sock0)
504 sk = gtp->sock0->sk;
505 else
506 sk = NULL;
507 break;
508 case GTP_V1:
509 if (gtp->sock1u)
510 sk = gtp->sock1u->sk;
511 else
512 sk = NULL;
513 break;
514 default:
515 return -ENOENT;
516 }
517
518 if (!sk) {
519 netdev_dbg(dev, "no userspace socket is available, skip\n");
520 return -ENOENT;
521 }
522
523 rt = ip4_route_output_gtp(sock_net(sk), &fl4, gtp->sock0->sk,
524 pctx->sgsn_addr_ip4.s_addr);
525 if (IS_ERR(rt)) {
526 netdev_dbg(dev, "no route to SSGN %pI4\n",
527 &pctx->sgsn_addr_ip4.s_addr);
528 dev->stats.tx_carrier_errors++;
529 goto err;
530 }
531
532 if (rt->dst.dev == dev) {
533 netdev_dbg(dev, "circular route to SSGN %pI4\n",
534 &pctx->sgsn_addr_ip4.s_addr);
535 dev->stats.collisions++;
536 goto err_rt;
537 }
538
539 skb_dst_drop(skb);
540
541 /* This is similar to tnl_update_pmtu(). */
542 df = iph->frag_off;
543 if (df) {
544 mtu = dst_mtu(&rt->dst) - dev->hard_header_len -
545 sizeof(struct iphdr) - sizeof(struct udphdr);
546 switch (pctx->gtp_version) {
547 case GTP_V0:
548 mtu -= sizeof(struct gtp0_header);
549 break;
550 case GTP_V1:
551 mtu -= sizeof(struct gtp1_header);
552 break;
553 }
554 } else {
555 mtu = dst_mtu(&rt->dst);
556 }
557
558 rt->dst.ops->update_pmtu(&rt->dst, NULL, skb, mtu);
559
560 if (!skb_is_gso(skb) && (iph->frag_off & htons(IP_DF)) &&
561 mtu < ntohs(iph->tot_len)) {
562 netdev_dbg(dev, "packet too big, fragmentation needed\n");
563 memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
564 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
565 htonl(mtu));
566 goto err_rt;
567 }
568
569 gtp_set_pktinfo_ipv4(pktinfo, sk, iph, pctx, rt, &fl4, dev);
570 gtp_push_header(skb, pktinfo);
571
572 return 0;
573err_rt:
574 ip_rt_put(rt);
575err:
576 return -EBADMSG;
577}
578
579static netdev_tx_t gtp_dev_xmit(struct sk_buff *skb, struct net_device *dev)
580{
581 unsigned int proto = ntohs(skb->protocol);
582 struct gtp_pktinfo pktinfo;
583 int err;
584
585 /* Ensure there is sufficient headroom. */
586 if (skb_cow_head(skb, dev->needed_headroom))
587 goto tx_err;
588
589 skb_reset_inner_headers(skb);
590
591 /* PDP context lookups in gtp_build_skb_*() need rcu read-side lock. */
592 rcu_read_lock();
593 switch (proto) {
594 case ETH_P_IP:
595 err = gtp_build_skb_ip4(skb, dev, &pktinfo);
596 break;
597 default:
598 err = -EOPNOTSUPP;
599 break;
600 }
601 rcu_read_unlock();
602
603 if (err < 0)
604 goto tx_err;
605
606 switch (proto) {
607 case ETH_P_IP:
608 netdev_dbg(pktinfo.dev, "gtp -> IP src: %pI4 dst: %pI4\n",
609 &pktinfo.iph->saddr, &pktinfo.iph->daddr);
610 udp_tunnel_xmit_skb(pktinfo.rt, pktinfo.sk, skb,
611 pktinfo.fl4.saddr, pktinfo.fl4.daddr,
612 pktinfo.iph->tos,
613 ip4_dst_hoplimit(&pktinfo.rt->dst),
614 0,
615 pktinfo.gtph_port, pktinfo.gtph_port,
616 true, false);
617 break;
618 }
619
620 return NETDEV_TX_OK;
621tx_err:
622 dev->stats.tx_errors++;
623 dev_kfree_skb(skb);
624 return NETDEV_TX_OK;
625}
626
627static const struct net_device_ops gtp_netdev_ops = {
628 .ndo_init = gtp_dev_init,
629 .ndo_uninit = gtp_dev_uninit,
630 .ndo_start_xmit = gtp_dev_xmit,
631 .ndo_get_stats64 = ip_tunnel_get_stats64,
632};
633
634static void gtp_link_setup(struct net_device *dev)
635{
636 dev->netdev_ops = >p_netdev_ops;
637 dev->destructor = free_netdev;
638
639 dev->hard_header_len = 0;
640 dev->addr_len = 0;
641
642 /* Zero header length. */
643 dev->type = ARPHRD_NONE;
644 dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
645
646 dev->priv_flags |= IFF_NO_QUEUE;
647 dev->features |= NETIF_F_LLTX;
648 netif_keep_dst(dev);
649
650 /* Assume largest header, ie. GTPv0. */
651 dev->needed_headroom = LL_MAX_HEADER +
652 sizeof(struct iphdr) +
653 sizeof(struct udphdr) +
654 sizeof(struct gtp0_header);
655}
656
657static int gtp_hashtable_new(struct gtp_dev *gtp, int hsize);
658static void gtp_hashtable_free(struct gtp_dev *gtp);
659static int gtp_encap_enable(struct net_device *dev, struct gtp_dev *gtp,
660 int fd_gtp0, int fd_gtp1);
661
662static int gtp_newlink(struct net *src_net, struct net_device *dev,
663 struct nlattr *tb[], struct nlattr *data[])
664{
665 int hashsize, err, fd0, fd1;
666 struct gtp_dev *gtp;
667 struct gtp_net *gn;
668
669 if (!data[IFLA_GTP_FD0] || !data[IFLA_GTP_FD1])
670 return -EINVAL;
671
672 gtp = netdev_priv(dev);
673
674 fd0 = nla_get_u32(data[IFLA_GTP_FD0]);
675 fd1 = nla_get_u32(data[IFLA_GTP_FD1]);
676
677 err = gtp_encap_enable(dev, gtp, fd0, fd1);
678 if (err < 0)
679 goto out_err;
680
681 if (!data[IFLA_GTP_PDP_HASHSIZE])
682 hashsize = 1024;
683 else
684 hashsize = nla_get_u32(data[IFLA_GTP_PDP_HASHSIZE]);
685
686 err = gtp_hashtable_new(gtp, hashsize);
687 if (err < 0)
688 goto out_encap;
689
690 err = register_netdevice(dev);
691 if (err < 0) {
692 netdev_dbg(dev, "failed to register new netdev %d\n", err);
693 goto out_hashtable;
694 }
695
696 gn = net_generic(dev_net(dev), gtp_net_id);
697 list_add_rcu(>p->list, &gn->gtp_dev_list);
698
699 netdev_dbg(dev, "registered new GTP interface\n");
700
701 return 0;
702
703out_hashtable:
704 gtp_hashtable_free(gtp);
705out_encap:
706 gtp_encap_disable(gtp);
707out_err:
708 return err;
709}
710
711static void gtp_dellink(struct net_device *dev, struct list_head *head)
712{
713 struct gtp_dev *gtp = netdev_priv(dev);
714
715 gtp_encap_disable(gtp);
716 gtp_hashtable_free(gtp);
717 list_del_rcu(>p->list);
718 unregister_netdevice_queue(dev, head);
719}
720
721static const struct nla_policy gtp_policy[IFLA_GTP_MAX + 1] = {
722 [IFLA_GTP_FD0] = { .type = NLA_U32 },
723 [IFLA_GTP_FD1] = { .type = NLA_U32 },
724 [IFLA_GTP_PDP_HASHSIZE] = { .type = NLA_U32 },
725};
726
727static int gtp_validate(struct nlattr *tb[], struct nlattr *data[])
728{
729 if (!data)
730 return -EINVAL;
731
732 return 0;
733}
734
735static size_t gtp_get_size(const struct net_device *dev)
736{
737 return nla_total_size(sizeof(__u32)); /* IFLA_GTP_PDP_HASHSIZE */
738}
739
740static int gtp_fill_info(struct sk_buff *skb, const struct net_device *dev)
741{
742 struct gtp_dev *gtp = netdev_priv(dev);
743
744 if (nla_put_u32(skb, IFLA_GTP_PDP_HASHSIZE, gtp->hash_size))
745 goto nla_put_failure;
746
747 return 0;
748
749nla_put_failure:
750 return -EMSGSIZE;
751}
752
753static struct rtnl_link_ops gtp_link_ops __read_mostly = {
754 .kind = "gtp",
755 .maxtype = IFLA_GTP_MAX,
756 .policy = gtp_policy,
757 .priv_size = sizeof(struct gtp_dev),
758 .setup = gtp_link_setup,
759 .validate = gtp_validate,
760 .newlink = gtp_newlink,
761 .dellink = gtp_dellink,
762 .get_size = gtp_get_size,
763 .fill_info = gtp_fill_info,
764};
765
766static struct net *gtp_genl_get_net(struct net *src_net, struct nlattr *tb[])
767{
768 struct net *net;
769
770 /* Examine the link attributes and figure out which network namespace
771 * we are talking about.
772 */
773 if (tb[GTPA_NET_NS_FD])
774 net = get_net_ns_by_fd(nla_get_u32(tb[GTPA_NET_NS_FD]));
775 else
776 net = get_net(src_net);
777
778 return net;
779}
780
781static int gtp_hashtable_new(struct gtp_dev *gtp, int hsize)
782{
783 int i;
784
785 gtp->addr_hash = kmalloc(sizeof(struct hlist_head) * hsize, GFP_KERNEL);
786 if (gtp->addr_hash == NULL)
787 return -ENOMEM;
788
789 gtp->tid_hash = kmalloc(sizeof(struct hlist_head) * hsize, GFP_KERNEL);
790 if (gtp->tid_hash == NULL)
791 goto err1;
792
793 gtp->hash_size = hsize;
794
795 for (i = 0; i < hsize; i++) {
796 INIT_HLIST_HEAD(>p->addr_hash[i]);
797 INIT_HLIST_HEAD(>p->tid_hash[i]);
798 }
799 return 0;
800err1:
801 kfree(gtp->addr_hash);
802 return -ENOMEM;
803}
804
805static void gtp_hashtable_free(struct gtp_dev *gtp)
806{
807 struct pdp_ctx *pctx;
808 int i;
809
810 for (i = 0; i < gtp->hash_size; i++) {
811 hlist_for_each_entry_rcu(pctx, >p->tid_hash[i], hlist_tid) {
812 hlist_del_rcu(&pctx->hlist_tid);
813 hlist_del_rcu(&pctx->hlist_addr);
814 kfree_rcu(pctx, rcu_head);
815 }
816 }
817 synchronize_rcu();
818 kfree(gtp->addr_hash);
819 kfree(gtp->tid_hash);
820}
821
822static int gtp_encap_enable(struct net_device *dev, struct gtp_dev *gtp,
823 int fd_gtp0, int fd_gtp1)
824{
825 struct udp_tunnel_sock_cfg tuncfg = {NULL};
826 struct socket *sock0, *sock1u;
827 int err;
828
829 netdev_dbg(dev, "enable gtp on %d, %d\n", fd_gtp0, fd_gtp1);
830
831 sock0 = sockfd_lookup(fd_gtp0, &err);
832 if (sock0 == NULL) {
833 netdev_dbg(dev, "socket fd=%d not found (gtp0)\n", fd_gtp0);
834 return -ENOENT;
835 }
836
837 if (sock0->sk->sk_protocol != IPPROTO_UDP) {
838 netdev_dbg(dev, "socket fd=%d not UDP\n", fd_gtp0);
839 err = -EINVAL;
840 goto err1;
841 }
842
843 sock1u = sockfd_lookup(fd_gtp1, &err);
844 if (sock1u == NULL) {
845 netdev_dbg(dev, "socket fd=%d not found (gtp1u)\n", fd_gtp1);
846 err = -ENOENT;
847 goto err1;
848 }
849
850 if (sock1u->sk->sk_protocol != IPPROTO_UDP) {
851 netdev_dbg(dev, "socket fd=%d not UDP\n", fd_gtp1);
852 err = -EINVAL;
853 goto err2;
854 }
855
856 netdev_dbg(dev, "enable gtp on %p, %p\n", sock0, sock1u);
857
858 gtp->sock0 = sock0;
859 gtp->sock1u = sock1u;
860
861 tuncfg.sk_user_data = gtp;
862 tuncfg.encap_rcv = gtp_encap_recv;
863 tuncfg.encap_destroy = gtp_encap_destroy;
864
865 tuncfg.encap_type = UDP_ENCAP_GTP0;
866 setup_udp_tunnel_sock(sock_net(gtp->sock0->sk), gtp->sock0, &tuncfg);
867
868 tuncfg.encap_type = UDP_ENCAP_GTP1U;
869 setup_udp_tunnel_sock(sock_net(gtp->sock1u->sk), gtp->sock1u, &tuncfg);
870
871 err = 0;
872err2:
873 sockfd_put(sock1u);
874err1:
875 sockfd_put(sock0);
876 return err;
877}
878
879static struct net_device *gtp_find_dev(struct net *net, int ifindex)
880{
881 struct gtp_net *gn = net_generic(net, gtp_net_id);
882 struct gtp_dev *gtp;
883
884 list_for_each_entry_rcu(gtp, &gn->gtp_dev_list, list) {
885 if (ifindex == gtp->dev->ifindex)
886 return gtp->dev;
887 }
888 return NULL;
889}
890
891static void ipv4_pdp_fill(struct pdp_ctx *pctx, struct genl_info *info)
892{
893 pctx->gtp_version = nla_get_u32(info->attrs[GTPA_VERSION]);
894 pctx->af = AF_INET;
895 pctx->sgsn_addr_ip4.s_addr =
896 nla_get_be32(info->attrs[GTPA_SGSN_ADDRESS]);
897 pctx->ms_addr_ip4.s_addr =
898 nla_get_be32(info->attrs[GTPA_MS_ADDRESS]);
899
900 switch (pctx->gtp_version) {
901 case GTP_V0:
902 /* According to TS 09.60, sections 7.5.1 and 7.5.2, the flow
903 * label needs to be the same for uplink and downlink packets,
904 * so let's annotate this.
905 */
906 pctx->u.v0.tid = nla_get_u64(info->attrs[GTPA_TID]);
907 pctx->u.v0.flow = nla_get_u16(info->attrs[GTPA_FLOW]);
908 break;
909 case GTP_V1:
910 pctx->u.v1.i_tei = nla_get_u32(info->attrs[GTPA_I_TEI]);
911 pctx->u.v1.o_tei = nla_get_u32(info->attrs[GTPA_O_TEI]);
912 break;
913 default:
914 break;
915 }
916}
917
918static int ipv4_pdp_add(struct net_device *dev, struct genl_info *info)
919{
920 struct gtp_dev *gtp = netdev_priv(dev);
921 u32 hash_ms, hash_tid = 0;
922 struct pdp_ctx *pctx;
923 bool found = false;
924 __be32 ms_addr;
925
926 ms_addr = nla_get_be32(info->attrs[GTPA_MS_ADDRESS]);
927 hash_ms = ipv4_hashfn(ms_addr) % gtp->hash_size;
928
929 hlist_for_each_entry_rcu(pctx, >p->addr_hash[hash_ms], hlist_addr) {
930 if (pctx->ms_addr_ip4.s_addr == ms_addr) {
931 found = true;
932 break;
933 }
934 }
935
936 if (found) {
937 if (info->nlhdr->nlmsg_flags & NLM_F_EXCL)
938 return -EEXIST;
939 if (info->nlhdr->nlmsg_flags & NLM_F_REPLACE)
940 return -EOPNOTSUPP;
941
942 ipv4_pdp_fill(pctx, info);
943
944 if (pctx->gtp_version == GTP_V0)
945 netdev_dbg(dev, "GTPv0-U: update tunnel id = %llx (pdp %p)\n",
946 pctx->u.v0.tid, pctx);
947 else if (pctx->gtp_version == GTP_V1)
948 netdev_dbg(dev, "GTPv1-U: update tunnel id = %x/%x (pdp %p)\n",
949 pctx->u.v1.i_tei, pctx->u.v1.o_tei, pctx);
950
951 return 0;
952
953 }
954
955 pctx = kmalloc(sizeof(struct pdp_ctx), GFP_KERNEL);
956 if (pctx == NULL)
957 return -ENOMEM;
958
959 ipv4_pdp_fill(pctx, info);
960 atomic_set(&pctx->tx_seq, 0);
961
962 switch (pctx->gtp_version) {
963 case GTP_V0:
964 /* TS 09.60: "The flow label identifies unambiguously a GTP
965 * flow.". We use the tid for this instead, I cannot find a
966 * situation in which this doesn't unambiguosly identify the
967 * PDP context.
968 */
969 hash_tid = gtp0_hashfn(pctx->u.v0.tid) % gtp->hash_size;
970 break;
971 case GTP_V1:
972 hash_tid = gtp1u_hashfn(pctx->u.v1.i_tei) % gtp->hash_size;
973 break;
974 }
975
976 hlist_add_head_rcu(&pctx->hlist_addr, >p->addr_hash[hash_ms]);
977 hlist_add_head_rcu(&pctx->hlist_tid, >p->tid_hash[hash_tid]);
978
979 switch (pctx->gtp_version) {
980 case GTP_V0:
981 netdev_dbg(dev, "GTPv0-U: new PDP ctx id=%llx ssgn=%pI4 ms=%pI4 (pdp=%p)\n",
982 pctx->u.v0.tid, &pctx->sgsn_addr_ip4,
983 &pctx->ms_addr_ip4, pctx);
984 break;
985 case GTP_V1:
986 netdev_dbg(dev, "GTPv1-U: new PDP ctx id=%x/%x ssgn=%pI4 ms=%pI4 (pdp=%p)\n",
987 pctx->u.v1.i_tei, pctx->u.v1.o_tei,
988 &pctx->sgsn_addr_ip4, &pctx->ms_addr_ip4, pctx);
989 break;
990 }
991
992 return 0;
993}
994
995static int gtp_genl_new_pdp(struct sk_buff *skb, struct genl_info *info)
996{
997 struct net_device *dev;
998 struct net *net;
999
1000 if (!info->attrs[GTPA_VERSION] ||
1001 !info->attrs[GTPA_LINK] ||
1002 !info->attrs[GTPA_SGSN_ADDRESS] ||
1003 !info->attrs[GTPA_MS_ADDRESS])
1004 return -EINVAL;
1005
1006 switch (nla_get_u32(info->attrs[GTPA_VERSION])) {
1007 case GTP_V0:
1008 if (!info->attrs[GTPA_TID] ||
1009 !info->attrs[GTPA_FLOW])
1010 return -EINVAL;
1011 break;
1012 case GTP_V1:
1013 if (!info->attrs[GTPA_I_TEI] ||
1014 !info->attrs[GTPA_O_TEI])
1015 return -EINVAL;
1016 break;
1017
1018 default:
1019 return -EINVAL;
1020 }
1021
1022 net = gtp_genl_get_net(sock_net(skb->sk), info->attrs);
1023 if (IS_ERR(net))
1024 return PTR_ERR(net);
1025
1026 /* Check if there's an existing gtpX device to configure */
1027 dev = gtp_find_dev(net, nla_get_u32(info->attrs[GTPA_LINK]));
1028 if (dev == NULL) {
1029 put_net(net);
1030 return -ENODEV;
1031 }
1032 put_net(net);
1033
1034 return ipv4_pdp_add(dev, info);
1035}
1036
1037static int gtp_genl_del_pdp(struct sk_buff *skb, struct genl_info *info)
1038{
1039 struct net_device *dev;
1040 struct pdp_ctx *pctx;
1041 struct gtp_dev *gtp;
1042 struct net *net;
1043
1044 if (!info->attrs[GTPA_VERSION] ||
1045 !info->attrs[GTPA_LINK])
1046 return -EINVAL;
1047
1048 net = gtp_genl_get_net(sock_net(skb->sk), info->attrs);
1049 if (IS_ERR(net))
1050 return PTR_ERR(net);
1051
1052 /* Check if there's an existing gtpX device to configure */
1053 dev = gtp_find_dev(net, nla_get_u32(info->attrs[GTPA_LINK]));
1054 if (dev == NULL) {
1055 put_net(net);
1056 return -ENODEV;
1057 }
1058 put_net(net);
1059
1060 gtp = netdev_priv(dev);
1061
1062 switch (nla_get_u32(info->attrs[GTPA_VERSION])) {
1063 case GTP_V0:
1064 if (!info->attrs[GTPA_TID])
1065 return -EINVAL;
1066 pctx = gtp0_pdp_find(gtp, nla_get_u64(info->attrs[GTPA_TID]));
1067 break;
1068 case GTP_V1:
1069 if (!info->attrs[GTPA_I_TEI])
1070 return -EINVAL;
1071 pctx = gtp1_pdp_find(gtp, nla_get_u64(info->attrs[GTPA_I_TEI]));
1072 break;
1073
1074 default:
1075 return -EINVAL;
1076 }
1077
1078 if (pctx == NULL)
1079 return -ENOENT;
1080
1081 if (pctx->gtp_version == GTP_V0)
1082 netdev_dbg(dev, "GTPv0-U: deleting tunnel id = %llx (pdp %p)\n",
1083 pctx->u.v0.tid, pctx);
1084 else if (pctx->gtp_version == GTP_V1)
1085 netdev_dbg(dev, "GTPv1-U: deleting tunnel id = %x/%x (pdp %p)\n",
1086 pctx->u.v1.i_tei, pctx->u.v1.o_tei, pctx);
1087
1088 hlist_del_rcu(&pctx->hlist_tid);
1089 hlist_del_rcu(&pctx->hlist_addr);
1090 kfree_rcu(pctx, rcu_head);
1091
1092 return 0;
1093}
1094
1095static struct genl_family gtp_genl_family;
1096
1097static int gtp_genl_fill_info(struct sk_buff *skb, u32 snd_portid, u32 snd_seq,
1098 u32 type, struct pdp_ctx *pctx)
1099{
1100 void *genlh;
1101
1102 genlh = genlmsg_put(skb, snd_portid, snd_seq, >p_genl_family, 0,
1103 type);
1104 if (genlh == NULL)
1105 goto nlmsg_failure;
1106
1107 if (nla_put_u32(skb, GTPA_VERSION, pctx->gtp_version) ||
1108 nla_put_be32(skb, GTPA_SGSN_ADDRESS, pctx->sgsn_addr_ip4.s_addr) ||
1109 nla_put_be32(skb, GTPA_MS_ADDRESS, pctx->ms_addr_ip4.s_addr))
1110 goto nla_put_failure;
1111
1112 switch (pctx->gtp_version) {
1113 case GTP_V0:
1114 if (nla_put_u64_64bit(skb, GTPA_TID, pctx->u.v0.tid, GTPA_PAD) ||
1115 nla_put_u16(skb, GTPA_FLOW, pctx->u.v0.flow))
1116 goto nla_put_failure;
1117 break;
1118 case GTP_V1:
1119 if (nla_put_u32(skb, GTPA_I_TEI, pctx->u.v1.i_tei) ||
1120 nla_put_u32(skb, GTPA_O_TEI, pctx->u.v1.o_tei))
1121 goto nla_put_failure;
1122 break;
1123 }
1124 genlmsg_end(skb, genlh);
1125 return 0;
1126
1127nlmsg_failure:
1128nla_put_failure:
1129 genlmsg_cancel(skb, genlh);
1130 return -EMSGSIZE;
1131}
1132
1133static int gtp_genl_get_pdp(struct sk_buff *skb, struct genl_info *info)
1134{
1135 struct pdp_ctx *pctx = NULL;
1136 struct net_device *dev;
1137 struct sk_buff *skb2;
1138 struct gtp_dev *gtp;
1139 u32 gtp_version;
1140 struct net *net;
1141 int err;
1142
1143 if (!info->attrs[GTPA_VERSION] ||
1144 !info->attrs[GTPA_LINK])
1145 return -EINVAL;
1146
1147 gtp_version = nla_get_u32(info->attrs[GTPA_VERSION]);
1148 switch (gtp_version) {
1149 case GTP_V0:
1150 case GTP_V1:
1151 break;
1152 default:
1153 return -EINVAL;
1154 }
1155
1156 net = gtp_genl_get_net(sock_net(skb->sk), info->attrs);
1157 if (IS_ERR(net))
1158 return PTR_ERR(net);
1159
1160 /* Check if there's an existing gtpX device to configure */
1161 dev = gtp_find_dev(net, nla_get_u32(info->attrs[GTPA_LINK]));
1162 if (dev == NULL) {
1163 put_net(net);
1164 return -ENODEV;
1165 }
1166 put_net(net);
1167
1168 gtp = netdev_priv(dev);
1169
1170 rcu_read_lock();
1171 if (gtp_version == GTP_V0 &&
1172 info->attrs[GTPA_TID]) {
1173 u64 tid = nla_get_u64(info->attrs[GTPA_TID]);
1174
1175 pctx = gtp0_pdp_find(gtp, tid);
1176 } else if (gtp_version == GTP_V1 &&
1177 info->attrs[GTPA_I_TEI]) {
1178 u32 tid = nla_get_u32(info->attrs[GTPA_I_TEI]);
1179
1180 pctx = gtp1_pdp_find(gtp, tid);
1181 } else if (info->attrs[GTPA_MS_ADDRESS]) {
1182 __be32 ip = nla_get_be32(info->attrs[GTPA_MS_ADDRESS]);
1183
1184 pctx = ipv4_pdp_find(gtp, ip);
1185 }
1186
1187 if (pctx == NULL) {
1188 err = -ENOENT;
1189 goto err_unlock;
1190 }
1191
1192 skb2 = genlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC);
1193 if (skb2 == NULL) {
1194 err = -ENOMEM;
1195 goto err_unlock;
1196 }
1197
1198 err = gtp_genl_fill_info(skb2, NETLINK_CB(skb).portid,
1199 info->snd_seq, info->nlhdr->nlmsg_type, pctx);
1200 if (err < 0)
1201 goto err_unlock_free;
1202
1203 rcu_read_unlock();
1204 return genlmsg_unicast(genl_info_net(info), skb2, info->snd_portid);
1205
1206err_unlock_free:
1207 kfree_skb(skb2);
1208err_unlock:
1209 rcu_read_unlock();
1210 return err;
1211}
1212
1213static int gtp_genl_dump_pdp(struct sk_buff *skb,
1214 struct netlink_callback *cb)
1215{
1216 struct gtp_dev *last_gtp = (struct gtp_dev *)cb->args[2], *gtp;
1217 struct net *net = sock_net(skb->sk);
1218 struct gtp_net *gn = net_generic(net, gtp_net_id);
1219 unsigned long tid = cb->args[1];
1220 int i, k = cb->args[0], ret;
1221 struct pdp_ctx *pctx;
1222
1223 if (cb->args[4])
1224 return 0;
1225
1226 list_for_each_entry_rcu(gtp, &gn->gtp_dev_list, list) {
1227 if (last_gtp && last_gtp != gtp)
1228 continue;
1229 else
1230 last_gtp = NULL;
1231
1232 for (i = k; i < gtp->hash_size; i++) {
1233 hlist_for_each_entry_rcu(pctx, >p->tid_hash[i], hlist_tid) {
1234 if (tid && tid != pctx->u.tid)
1235 continue;
1236 else
1237 tid = 0;
1238
1239 ret = gtp_genl_fill_info(skb,
1240 NETLINK_CB(cb->skb).portid,
1241 cb->nlh->nlmsg_seq,
1242 cb->nlh->nlmsg_type, pctx);
1243 if (ret < 0) {
1244 cb->args[0] = i;
1245 cb->args[1] = pctx->u.tid;
1246 cb->args[2] = (unsigned long)gtp;
1247 goto out;
1248 }
1249 }
1250 }
1251 }
1252 cb->args[4] = 1;
1253out:
1254 return skb->len;
1255}
1256
1257static struct nla_policy gtp_genl_policy[GTPA_MAX + 1] = {
1258 [GTPA_LINK] = { .type = NLA_U32, },
1259 [GTPA_VERSION] = { .type = NLA_U32, },
1260 [GTPA_TID] = { .type = NLA_U64, },
1261 [GTPA_SGSN_ADDRESS] = { .type = NLA_U32, },
1262 [GTPA_MS_ADDRESS] = { .type = NLA_U32, },
1263 [GTPA_FLOW] = { .type = NLA_U16, },
1264 [GTPA_NET_NS_FD] = { .type = NLA_U32, },
1265 [GTPA_I_TEI] = { .type = NLA_U32, },
1266 [GTPA_O_TEI] = { .type = NLA_U32, },
1267};
1268
1269static const struct genl_ops gtp_genl_ops[] = {
1270 {
1271 .cmd = GTP_CMD_NEWPDP,
1272 .doit = gtp_genl_new_pdp,
1273 .policy = gtp_genl_policy,
1274 .flags = GENL_ADMIN_PERM,
1275 },
1276 {
1277 .cmd = GTP_CMD_DELPDP,
1278 .doit = gtp_genl_del_pdp,
1279 .policy = gtp_genl_policy,
1280 .flags = GENL_ADMIN_PERM,
1281 },
1282 {
1283 .cmd = GTP_CMD_GETPDP,
1284 .doit = gtp_genl_get_pdp,
1285 .dumpit = gtp_genl_dump_pdp,
1286 .policy = gtp_genl_policy,
1287 .flags = GENL_ADMIN_PERM,
1288 },
1289};
1290
1291static struct genl_family gtp_genl_family __ro_after_init = {
1292 .name = "gtp",
1293 .version = 0,
1294 .hdrsize = 0,
1295 .maxattr = GTPA_MAX,
1296 .netnsok = true,
1297 .module = THIS_MODULE,
1298 .ops = gtp_genl_ops,
1299 .n_ops = ARRAY_SIZE(gtp_genl_ops),
1300};
1301
1302static int __net_init gtp_net_init(struct net *net)
1303{
1304 struct gtp_net *gn = net_generic(net, gtp_net_id);
1305
1306 INIT_LIST_HEAD(&gn->gtp_dev_list);
1307 return 0;
1308}
1309
1310static void __net_exit gtp_net_exit(struct net *net)
1311{
1312 struct gtp_net *gn = net_generic(net, gtp_net_id);
1313 struct gtp_dev *gtp;
1314 LIST_HEAD(list);
1315
1316 rtnl_lock();
1317 list_for_each_entry(gtp, &gn->gtp_dev_list, list)
1318 gtp_dellink(gtp->dev, &list);
1319
1320 unregister_netdevice_many(&list);
1321 rtnl_unlock();
1322}
1323
1324static struct pernet_operations gtp_net_ops = {
1325 .init = gtp_net_init,
1326 .exit = gtp_net_exit,
1327 .id = >p_net_id,
1328 .size = sizeof(struct gtp_net),
1329};
1330
1331static int __init gtp_init(void)
1332{
1333 int err;
1334
1335 get_random_bytes(>p_h_initval, sizeof(gtp_h_initval));
1336
1337 err = rtnl_link_register(>p_link_ops);
1338 if (err < 0)
1339 goto error_out;
1340
1341 err = genl_register_family(>p_genl_family);
1342 if (err < 0)
1343 goto unreg_rtnl_link;
1344
1345 err = register_pernet_subsys(>p_net_ops);
1346 if (err < 0)
1347 goto unreg_genl_family;
1348
1349 pr_info("GTP module loaded (pdp ctx size %Zd bytes)\n",
1350 sizeof(struct pdp_ctx));
1351 return 0;
1352
1353unreg_genl_family:
1354 genl_unregister_family(>p_genl_family);
1355unreg_rtnl_link:
1356 rtnl_link_unregister(>p_link_ops);
1357error_out:
1358 pr_err("error loading GTP module loaded\n");
1359 return err;
1360}
1361late_initcall(gtp_init);
1362
1363static void __exit gtp_fini(void)
1364{
1365 unregister_pernet_subsys(>p_net_ops);
1366 genl_unregister_family(>p_genl_family);
1367 rtnl_link_unregister(>p_link_ops);
1368
1369 pr_info("GTP module unloaded\n");
1370}
1371module_exit(gtp_fini);
1372
1373MODULE_LICENSE("GPL");
1374MODULE_AUTHOR("Harald Welte <hwelte@sysmocom.de>");
1375MODULE_DESCRIPTION("Interface driver for GTP encapsulated traffic");
1376MODULE_ALIAS_RTNL_LINK("gtp");
1377MODULE_ALIAS_GENL_FAMILY("gtp");