xref: /linux/drivers/net/gtp.c (revision 6f0310a126f1a46cac366327751bb7eb8941bdde)
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. */
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_device	*dev;
73 
74 	unsigned int		hash_size;
75 	struct hlist_head	*tid_hash;
76 	struct hlist_head	*addr_hash;
77 };
78 
79 static unsigned int gtp_net_id __read_mostly;
80 
81 struct gtp_net {
82 	struct list_head gtp_dev_list;
83 };
84 
85 static u32 gtp_h_initval;
86 
87 static 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 
93 static inline u32 gtp1u_hashfn(u32 tid)
94 {
95 	return jhash_1word(tid, gtp_h_initval);
96 }
97 
98 static 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. */
104 static 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 = &gtp->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. */
120 static 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 = &gtp->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. */
136 static 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 = &gtp->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 
152 static 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  */
168 static 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. */
179 static 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);
216 out_rcu:
217 	rcu_read_unlock();
218 	return ret;
219 }
220 
221 static 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);
273 out_rcu:
274 	rcu_read_unlock();
275 	return ret;
276 }
277 
278 static 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 
293 static 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  */
305 static 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 
365 static 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 
378 static 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 
386 static 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 
399 static 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 
416 static 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 
439 struct 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 
449 static 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 
463 static 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 
477 static 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;
573 err_rt:
574 	ip_rt_put(rt);
575 err:
576 	return -EBADMSG;
577 }
578 
579 static 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;
621 tx_err:
622 	dev->stats.tx_errors++;
623 	dev_kfree_skb(skb);
624 	return NETDEV_TX_OK;
625 }
626 
627 static 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 
634 static void gtp_link_setup(struct net_device *dev)
635 {
636 	dev->netdev_ops		= &gtp_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 
657 static int gtp_hashtable_new(struct gtp_dev *gtp, int hsize);
658 static void gtp_hashtable_free(struct gtp_dev *gtp);
659 static int gtp_encap_enable(struct net_device *dev, struct gtp_dev *gtp,
660 			    int fd_gtp0, int fd_gtp1);
661 
662 static 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(&gtp->list, &gn->gtp_dev_list);
698 
699 	netdev_dbg(dev, "registered new GTP interface\n");
700 
701 	return 0;
702 
703 out_hashtable:
704 	gtp_hashtable_free(gtp);
705 out_encap:
706 	gtp_encap_disable(gtp);
707 out_err:
708 	return err;
709 }
710 
711 static 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(&gtp->list);
718 	unregister_netdevice_queue(dev, head);
719 }
720 
721 static 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 
727 static int gtp_validate(struct nlattr *tb[], struct nlattr *data[])
728 {
729 	if (!data)
730 		return -EINVAL;
731 
732 	return 0;
733 }
734 
735 static size_t gtp_get_size(const struct net_device *dev)
736 {
737 	return nla_total_size(sizeof(__u32));	/* IFLA_GTP_PDP_HASHSIZE */
738 }
739 
740 static 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 
749 nla_put_failure:
750 	return -EMSGSIZE;
751 }
752 
753 static 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 
766 static 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 
781 static 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(&gtp->addr_hash[i]);
797 		INIT_HLIST_HEAD(&gtp->tid_hash[i]);
798 	}
799 	return 0;
800 err1:
801 	kfree(gtp->addr_hash);
802 	return -ENOMEM;
803 }
804 
805 static 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, &gtp->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 
822 static 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;
872 err2:
873 	sockfd_put(sock1u);
874 err1:
875 	sockfd_put(sock0);
876 	return err;
877 }
878 
879 static 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 
891 static 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 
918 static 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, &gtp->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, &gtp->addr_hash[hash_ms]);
977 	hlist_add_head_rcu(&pctx->hlist_tid, &gtp->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 
995 static 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 
1037 static 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 
1095 static struct genl_family gtp_genl_family;
1096 
1097 static 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, &gtp_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 
1127 nlmsg_failure:
1128 nla_put_failure:
1129 	genlmsg_cancel(skb, genlh);
1130 	return -EMSGSIZE;
1131 }
1132 
1133 static 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 
1206 err_unlock_free:
1207 	kfree_skb(skb2);
1208 err_unlock:
1209 	rcu_read_unlock();
1210 	return err;
1211 }
1212 
1213 static 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, &gtp->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;
1253 out:
1254 	return skb->len;
1255 }
1256 
1257 static 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 
1269 static 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 
1291 static 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 
1302 static 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 
1310 static 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 
1324 static struct pernet_operations gtp_net_ops = {
1325 	.init	= gtp_net_init,
1326 	.exit	= gtp_net_exit,
1327 	.id	= &gtp_net_id,
1328 	.size	= sizeof(struct gtp_net),
1329 };
1330 
1331 static int __init gtp_init(void)
1332 {
1333 	int err;
1334 
1335 	get_random_bytes(&gtp_h_initval, sizeof(gtp_h_initval));
1336 
1337 	err = rtnl_link_register(&gtp_link_ops);
1338 	if (err < 0)
1339 		goto error_out;
1340 
1341 	err = genl_register_family(&gtp_genl_family);
1342 	if (err < 0)
1343 		goto unreg_rtnl_link;
1344 
1345 	err = register_pernet_subsys(&gtp_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 
1353 unreg_genl_family:
1354 	genl_unregister_family(&gtp_genl_family);
1355 unreg_rtnl_link:
1356 	rtnl_link_unregister(&gtp_link_ops);
1357 error_out:
1358 	pr_err("error loading GTP module loaded\n");
1359 	return err;
1360 }
1361 late_initcall(gtp_init);
1362 
1363 static void __exit gtp_fini(void)
1364 {
1365 	unregister_pernet_subsys(&gtp_net_ops);
1366 	genl_unregister_family(&gtp_genl_family);
1367 	rtnl_link_unregister(&gtp_link_ops);
1368 
1369 	pr_info("GTP module unloaded\n");
1370 }
1371 module_exit(gtp_fini);
1372 
1373 MODULE_LICENSE("GPL");
1374 MODULE_AUTHOR("Harald Welte <hwelte@sysmocom.de>");
1375 MODULE_DESCRIPTION("Interface driver for GTP encapsulated traffic");
1376 MODULE_ALIAS_RTNL_LINK("gtp");
1377 MODULE_ALIAS_GENL_FAMILY("gtp");
1378