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/inet_dscp.h>
27 #include <net/inet_sock.h>
28 #include <net/ip.h>
29 #include <net/ipv6.h>
30 #include <net/udp.h>
31 #include <net/udp_tunnel.h>
32 #include <net/icmp.h>
33 #include <net/xfrm.h>
34 #include <net/genetlink.h>
35 #include <net/netns/generic.h>
36 #include <net/gtp.h>
37
38 /* An active session for the subscriber. */
39 struct pdp_ctx {
40 struct hlist_node hlist_tid;
41 struct hlist_node hlist_addr;
42
43 union {
44 struct {
45 u64 tid;
46 u16 flow;
47 } v0;
48 struct {
49 u32 i_tei;
50 u32 o_tei;
51 } v1;
52 } u;
53 u8 gtp_version;
54 u16 af;
55
56 union {
57 struct in_addr addr;
58 struct in6_addr addr6;
59 } ms;
60 union {
61 struct in_addr addr;
62 struct in6_addr addr6;
63 } peer;
64
65 struct sock *sk;
66 struct net_device *dev;
67
68 atomic_t tx_seq;
69 struct rcu_head rcu_head;
70 };
71
72 /* One instance of the GTP device. */
73 struct gtp_dev {
74 struct list_head list;
75
76 struct sock *sk0;
77 struct sock *sk1u;
78 u8 sk_created;
79
80 struct net_device *dev;
81 struct net *net;
82
83 unsigned int role;
84 unsigned int hash_size;
85 struct hlist_head *tid_hash;
86 struct hlist_head *addr_hash;
87
88 u8 restart_count;
89 };
90
91 struct echo_info {
92 u16 af;
93 u8 gtp_version;
94
95 union {
96 struct in_addr addr;
97 } ms;
98 union {
99 struct in_addr addr;
100 } peer;
101 };
102
103 static unsigned int gtp_net_id __read_mostly;
104
105 struct gtp_net {
106 struct list_head gtp_dev_list;
107 };
108
109 static u32 gtp_h_initval;
110
111 static struct genl_family gtp_genl_family;
112
113 enum gtp_multicast_groups {
114 GTP_GENL_MCGRP,
115 };
116
117 static const struct genl_multicast_group gtp_genl_mcgrps[] = {
118 [GTP_GENL_MCGRP] = { .name = GTP_GENL_MCGRP_NAME },
119 };
120
121 static void pdp_context_delete(struct pdp_ctx *pctx);
122
gtp0_hashfn(u64 tid)123 static inline u32 gtp0_hashfn(u64 tid)
124 {
125 u32 *tid32 = (u32 *) &tid;
126 return jhash_2words(tid32[0], tid32[1], gtp_h_initval);
127 }
128
gtp1u_hashfn(u32 tid)129 static inline u32 gtp1u_hashfn(u32 tid)
130 {
131 return jhash_1word(tid, gtp_h_initval);
132 }
133
ipv4_hashfn(__be32 ip)134 static inline u32 ipv4_hashfn(__be32 ip)
135 {
136 return jhash_1word((__force u32)ip, gtp_h_initval);
137 }
138
ipv6_hashfn(const struct in6_addr * ip6)139 static u32 ipv6_hashfn(const struct in6_addr *ip6)
140 {
141 return jhash_2words((__force u32)ip6->s6_addr32[0],
142 (__force u32)ip6->s6_addr32[1], gtp_h_initval);
143 }
144
145 /* Resolve a PDP context structure based on the 64bit TID. */
gtp0_pdp_find(struct gtp_dev * gtp,u64 tid,u16 family)146 static struct pdp_ctx *gtp0_pdp_find(struct gtp_dev *gtp, u64 tid, u16 family)
147 {
148 struct hlist_head *head;
149 struct pdp_ctx *pdp;
150
151 head = >p->tid_hash[gtp0_hashfn(tid) % gtp->hash_size];
152
153 hlist_for_each_entry_rcu(pdp, head, hlist_tid) {
154 if (pdp->af == family &&
155 pdp->gtp_version == GTP_V0 &&
156 pdp->u.v0.tid == tid)
157 return pdp;
158 }
159 return NULL;
160 }
161
162 /* Resolve a PDP context structure based on the 32bit TEI. */
gtp1_pdp_find(struct gtp_dev * gtp,u32 tid,u16 family)163 static struct pdp_ctx *gtp1_pdp_find(struct gtp_dev *gtp, u32 tid, u16 family)
164 {
165 struct hlist_head *head;
166 struct pdp_ctx *pdp;
167
168 head = >p->tid_hash[gtp1u_hashfn(tid) % gtp->hash_size];
169
170 hlist_for_each_entry_rcu(pdp, head, hlist_tid) {
171 if (pdp->af == family &&
172 pdp->gtp_version == GTP_V1 &&
173 pdp->u.v1.i_tei == tid)
174 return pdp;
175 }
176 return NULL;
177 }
178
179 /* Resolve a PDP context based on IPv4 address of MS. */
ipv4_pdp_find(struct gtp_dev * gtp,__be32 ms_addr)180 static struct pdp_ctx *ipv4_pdp_find(struct gtp_dev *gtp, __be32 ms_addr)
181 {
182 struct hlist_head *head;
183 struct pdp_ctx *pdp;
184
185 head = >p->addr_hash[ipv4_hashfn(ms_addr) % gtp->hash_size];
186
187 hlist_for_each_entry_rcu(pdp, head, hlist_addr) {
188 if (pdp->af == AF_INET &&
189 pdp->ms.addr.s_addr == ms_addr)
190 return pdp;
191 }
192
193 return NULL;
194 }
195
196 /* 3GPP TS 29.060: PDN Connection: the association between a MS represented by
197 * [...] one IPv6 *prefix* and a PDN represented by an APN.
198 *
199 * Then, 3GPP TS 29.061, Section 11.2.1.3 says: The size of the prefix shall be
200 * according to the maximum prefix length for a global IPv6 address as
201 * specified in the IPv6 Addressing Architecture, see RFC 4291.
202 *
203 * Finally, RFC 4291 section 2.5.4 states: All Global Unicast addresses other
204 * than those that start with binary 000 have a 64-bit interface ID field
205 * (i.e., n + m = 64).
206 */
ipv6_pdp_addr_equal(const struct in6_addr * a,const struct in6_addr * b)207 static bool ipv6_pdp_addr_equal(const struct in6_addr *a,
208 const struct in6_addr *b)
209 {
210 return a->s6_addr32[0] == b->s6_addr32[0] &&
211 a->s6_addr32[1] == b->s6_addr32[1];
212 }
213
ipv6_pdp_find(struct gtp_dev * gtp,const struct in6_addr * ms_addr)214 static struct pdp_ctx *ipv6_pdp_find(struct gtp_dev *gtp,
215 const struct in6_addr *ms_addr)
216 {
217 struct hlist_head *head;
218 struct pdp_ctx *pdp;
219
220 head = >p->addr_hash[ipv6_hashfn(ms_addr) % gtp->hash_size];
221
222 hlist_for_each_entry_rcu(pdp, head, hlist_addr) {
223 if (pdp->af == AF_INET6 &&
224 ipv6_pdp_addr_equal(&pdp->ms.addr6, ms_addr))
225 return pdp;
226 }
227
228 return NULL;
229 }
230
gtp_check_ms_ipv4(struct sk_buff * skb,struct pdp_ctx * pctx,unsigned int hdrlen,unsigned int role)231 static bool gtp_check_ms_ipv4(struct sk_buff *skb, struct pdp_ctx *pctx,
232 unsigned int hdrlen, unsigned int role)
233 {
234 struct iphdr *iph;
235
236 if (!pskb_may_pull(skb, hdrlen + sizeof(struct iphdr)))
237 return false;
238
239 iph = (struct iphdr *)(skb->data + hdrlen);
240
241 if (role == GTP_ROLE_SGSN)
242 return iph->daddr == pctx->ms.addr.s_addr;
243 else
244 return iph->saddr == pctx->ms.addr.s_addr;
245 }
246
gtp_check_ms_ipv6(struct sk_buff * skb,struct pdp_ctx * pctx,unsigned int hdrlen,unsigned int role)247 static bool gtp_check_ms_ipv6(struct sk_buff *skb, struct pdp_ctx *pctx,
248 unsigned int hdrlen, unsigned int role)
249 {
250 struct ipv6hdr *ip6h;
251 int ret;
252
253 if (!pskb_may_pull(skb, hdrlen + sizeof(struct ipv6hdr)))
254 return false;
255
256 ip6h = (struct ipv6hdr *)(skb->data + hdrlen);
257
258 if ((ipv6_addr_type(&ip6h->saddr) & IPV6_ADDR_LINKLOCAL) ||
259 (ipv6_addr_type(&ip6h->daddr) & IPV6_ADDR_LINKLOCAL))
260 return false;
261
262 if (role == GTP_ROLE_SGSN) {
263 ret = ipv6_pdp_addr_equal(&ip6h->daddr, &pctx->ms.addr6);
264 } else {
265 ret = ipv6_pdp_addr_equal(&ip6h->saddr, &pctx->ms.addr6);
266 }
267
268 return ret;
269 }
270
271 /* Check if the inner IP address in this packet is assigned to any
272 * existing mobile subscriber.
273 */
gtp_check_ms(struct sk_buff * skb,struct pdp_ctx * pctx,unsigned int hdrlen,unsigned int role,__u16 inner_proto)274 static bool gtp_check_ms(struct sk_buff *skb, struct pdp_ctx *pctx,
275 unsigned int hdrlen, unsigned int role,
276 __u16 inner_proto)
277 {
278 switch (inner_proto) {
279 case ETH_P_IP:
280 return gtp_check_ms_ipv4(skb, pctx, hdrlen, role);
281 case ETH_P_IPV6:
282 return gtp_check_ms_ipv6(skb, pctx, hdrlen, role);
283 }
284 return false;
285 }
286
gtp_inner_proto(struct sk_buff * skb,unsigned int hdrlen,__u16 * inner_proto)287 static int gtp_inner_proto(struct sk_buff *skb, unsigned int hdrlen,
288 __u16 *inner_proto)
289 {
290 __u8 *ip_version, _ip_version;
291
292 ip_version = skb_header_pointer(skb, hdrlen, sizeof(*ip_version),
293 &_ip_version);
294 if (!ip_version)
295 return -1;
296
297 switch (*ip_version & 0xf0) {
298 case 0x40:
299 *inner_proto = ETH_P_IP;
300 break;
301 case 0x60:
302 *inner_proto = ETH_P_IPV6;
303 break;
304 default:
305 return -1;
306 }
307
308 return 0;
309 }
310
gtp_rx(struct pdp_ctx * pctx,struct sk_buff * skb,unsigned int hdrlen,unsigned int role,__u16 inner_proto)311 static int gtp_rx(struct pdp_ctx *pctx, struct sk_buff *skb,
312 unsigned int hdrlen, unsigned int role, __u16 inner_proto)
313 {
314 if (!gtp_check_ms(skb, pctx, hdrlen, role, inner_proto)) {
315 netdev_dbg(pctx->dev, "No PDP ctx for this MS\n");
316 return 1;
317 }
318
319 /* Get rid of the GTP + UDP headers. */
320 if (iptunnel_pull_header(skb, hdrlen, htons(inner_proto),
321 !net_eq(sock_net(pctx->sk), dev_net(pctx->dev)))) {
322 pctx->dev->stats.rx_length_errors++;
323 goto err;
324 }
325
326 netdev_dbg(pctx->dev, "forwarding packet from GGSN to uplink\n");
327
328 /* Now that the UDP and the GTP header have been removed, set up the
329 * new network header. This is required by the upper layer to
330 * calculate the transport header.
331 */
332 skb_reset_network_header(skb);
333 skb_reset_mac_header(skb);
334
335 skb->dev = pctx->dev;
336
337 dev_sw_netstats_rx_add(pctx->dev, skb->len);
338
339 __netif_rx(skb);
340 return 0;
341
342 err:
343 pctx->dev->stats.rx_dropped++;
344 return -1;
345 }
346
ip4_route_output_gtp(struct flowi4 * fl4,const struct sock * sk,__be32 daddr,__be32 saddr)347 static struct rtable *ip4_route_output_gtp(struct flowi4 *fl4,
348 const struct sock *sk,
349 __be32 daddr, __be32 saddr)
350 {
351 memset(fl4, 0, sizeof(*fl4));
352 fl4->flowi4_oif = sk->sk_bound_dev_if;
353 fl4->daddr = daddr;
354 fl4->saddr = saddr;
355 fl4->flowi4_tos = inet_dscp_to_dsfield(inet_sk_dscp(inet_sk(sk)));
356 fl4->flowi4_scope = ip_sock_rt_scope(sk);
357 fl4->flowi4_proto = sk->sk_protocol;
358
359 return ip_route_output_key(sock_net(sk), fl4);
360 }
361
ip6_route_output_gtp(struct net * net,struct flowi6 * fl6,const struct sock * sk,const struct in6_addr * daddr,struct in6_addr * saddr)362 static struct rt6_info *ip6_route_output_gtp(struct net *net,
363 struct flowi6 *fl6,
364 const struct sock *sk,
365 const struct in6_addr *daddr,
366 struct in6_addr *saddr)
367 {
368 struct dst_entry *dst;
369
370 memset(fl6, 0, sizeof(*fl6));
371 fl6->flowi6_oif = sk->sk_bound_dev_if;
372 fl6->daddr = *daddr;
373 fl6->saddr = *saddr;
374 fl6->flowi6_proto = sk->sk_protocol;
375
376 dst = ipv6_stub->ipv6_dst_lookup_flow(net, sk, fl6, NULL);
377 if (IS_ERR(dst))
378 return ERR_PTR(-ENETUNREACH);
379
380 return (struct rt6_info *)dst;
381 }
382
383 /* GSM TS 09.60. 7.3
384 * In all Path Management messages:
385 * - TID: is not used and shall be set to 0.
386 * - Flow Label is not used and shall be set to 0
387 * In signalling messages:
388 * - number: this field is not yet used in signalling messages.
389 * It shall be set to 255 by the sender and shall be ignored
390 * by the receiver
391 * Returns true if the echo req was correct, false otherwise.
392 */
gtp0_validate_echo_hdr(struct gtp0_header * gtp0)393 static bool gtp0_validate_echo_hdr(struct gtp0_header *gtp0)
394 {
395 return !(gtp0->tid || (gtp0->flags ^ 0x1e) ||
396 gtp0->number != 0xff || gtp0->flow);
397 }
398
399 /* msg_type has to be GTP_ECHO_REQ or GTP_ECHO_RSP */
gtp0_build_echo_msg(struct gtp0_header * hdr,__u8 msg_type)400 static void gtp0_build_echo_msg(struct gtp0_header *hdr, __u8 msg_type)
401 {
402 int len_pkt, len_hdr;
403
404 hdr->flags = 0x1e; /* v0, GTP-non-prime. */
405 hdr->type = msg_type;
406 /* GSM TS 09.60. 7.3 In all Path Management Flow Label and TID
407 * are not used and shall be set to 0.
408 */
409 hdr->flow = 0;
410 hdr->tid = 0;
411 hdr->number = 0xff;
412 hdr->spare[0] = 0xff;
413 hdr->spare[1] = 0xff;
414 hdr->spare[2] = 0xff;
415
416 len_pkt = sizeof(struct gtp0_packet);
417 len_hdr = sizeof(struct gtp0_header);
418
419 if (msg_type == GTP_ECHO_RSP)
420 hdr->length = htons(len_pkt - len_hdr);
421 else
422 hdr->length = 0;
423 }
424
gtp0_send_echo_resp_ip(struct gtp_dev * gtp,struct sk_buff * skb)425 static int gtp0_send_echo_resp_ip(struct gtp_dev *gtp, struct sk_buff *skb)
426 {
427 struct iphdr *iph = ip_hdr(skb);
428 struct flowi4 fl4;
429 struct rtable *rt;
430
431 /* find route to the sender,
432 * src address becomes dst address and vice versa.
433 */
434 rt = ip4_route_output_gtp(&fl4, gtp->sk0, iph->saddr, iph->daddr);
435 if (IS_ERR(rt)) {
436 netdev_dbg(gtp->dev, "no route for echo response from %pI4\n",
437 &iph->saddr);
438 return -1;
439 }
440
441 udp_tunnel_xmit_skb(rt, gtp->sk0, skb,
442 fl4.saddr, fl4.daddr,
443 iph->tos,
444 ip4_dst_hoplimit(&rt->dst),
445 0,
446 htons(GTP0_PORT), htons(GTP0_PORT),
447 !net_eq(sock_net(gtp->sk1u),
448 dev_net(gtp->dev)),
449 false);
450
451 return 0;
452 }
453
gtp0_send_echo_resp(struct gtp_dev * gtp,struct sk_buff * skb)454 static int gtp0_send_echo_resp(struct gtp_dev *gtp, struct sk_buff *skb)
455 {
456 struct gtp0_packet *gtp_pkt;
457 struct gtp0_header *gtp0;
458 __be16 seq;
459
460 gtp0 = (struct gtp0_header *)(skb->data + sizeof(struct udphdr));
461
462 if (!gtp0_validate_echo_hdr(gtp0))
463 return -1;
464
465 seq = gtp0->seq;
466
467 /* pull GTP and UDP headers */
468 skb_pull_data(skb, sizeof(struct gtp0_header) + sizeof(struct udphdr));
469
470 gtp_pkt = skb_push(skb, sizeof(struct gtp0_packet));
471 memset(gtp_pkt, 0, sizeof(struct gtp0_packet));
472
473 gtp0_build_echo_msg(>p_pkt->gtp0_h, GTP_ECHO_RSP);
474
475 /* GSM TS 09.60. 7.3 The Sequence Number in a signalling response
476 * message shall be copied from the signalling request message
477 * that the GSN is replying to.
478 */
479 gtp_pkt->gtp0_h.seq = seq;
480
481 gtp_pkt->ie.tag = GTPIE_RECOVERY;
482 gtp_pkt->ie.val = gtp->restart_count;
483
484 switch (gtp->sk0->sk_family) {
485 case AF_INET:
486 if (gtp0_send_echo_resp_ip(gtp, skb) < 0)
487 return -1;
488 break;
489 case AF_INET6:
490 return -1;
491 }
492
493 return 0;
494 }
495
gtp_genl_fill_echo(struct sk_buff * skb,u32 snd_portid,u32 snd_seq,int flags,u32 type,struct echo_info echo)496 static int gtp_genl_fill_echo(struct sk_buff *skb, u32 snd_portid, u32 snd_seq,
497 int flags, u32 type, struct echo_info echo)
498 {
499 void *genlh;
500
501 genlh = genlmsg_put(skb, snd_portid, snd_seq, >p_genl_family, flags,
502 type);
503 if (!genlh)
504 goto failure;
505
506 if (nla_put_u32(skb, GTPA_VERSION, echo.gtp_version) ||
507 nla_put_be32(skb, GTPA_PEER_ADDRESS, echo.peer.addr.s_addr) ||
508 nla_put_be32(skb, GTPA_MS_ADDRESS, echo.ms.addr.s_addr))
509 goto failure;
510
511 genlmsg_end(skb, genlh);
512 return 0;
513
514 failure:
515 genlmsg_cancel(skb, genlh);
516 return -EMSGSIZE;
517 }
518
gtp0_handle_echo_resp_ip(struct sk_buff * skb,struct echo_info * echo)519 static void gtp0_handle_echo_resp_ip(struct sk_buff *skb, struct echo_info *echo)
520 {
521 struct iphdr *iph = ip_hdr(skb);
522
523 echo->ms.addr.s_addr = iph->daddr;
524 echo->peer.addr.s_addr = iph->saddr;
525 echo->gtp_version = GTP_V0;
526 }
527
gtp0_handle_echo_resp(struct gtp_dev * gtp,struct sk_buff * skb)528 static int gtp0_handle_echo_resp(struct gtp_dev *gtp, struct sk_buff *skb)
529 {
530 struct gtp0_header *gtp0;
531 struct echo_info echo;
532 struct sk_buff *msg;
533 int ret;
534
535 gtp0 = (struct gtp0_header *)(skb->data + sizeof(struct udphdr));
536
537 if (!gtp0_validate_echo_hdr(gtp0))
538 return -1;
539
540 switch (gtp->sk0->sk_family) {
541 case AF_INET:
542 gtp0_handle_echo_resp_ip(skb, &echo);
543 break;
544 case AF_INET6:
545 return -1;
546 }
547
548 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
549 if (!msg)
550 return -ENOMEM;
551
552 ret = gtp_genl_fill_echo(msg, 0, 0, 0, GTP_CMD_ECHOREQ, echo);
553 if (ret < 0) {
554 nlmsg_free(msg);
555 return ret;
556 }
557
558 return genlmsg_multicast_netns(>p_genl_family, dev_net(gtp->dev),
559 msg, 0, GTP_GENL_MCGRP, GFP_ATOMIC);
560 }
561
gtp_proto_to_family(__u16 proto)562 static int gtp_proto_to_family(__u16 proto)
563 {
564 switch (proto) {
565 case ETH_P_IP:
566 return AF_INET;
567 case ETH_P_IPV6:
568 return AF_INET6;
569 default:
570 WARN_ON_ONCE(1);
571 break;
572 }
573
574 return AF_UNSPEC;
575 }
576
577 /* 1 means pass up to the stack, -1 means drop and 0 means decapsulated. */
gtp0_udp_encap_recv(struct gtp_dev * gtp,struct sk_buff * skb)578 static int gtp0_udp_encap_recv(struct gtp_dev *gtp, struct sk_buff *skb)
579 {
580 unsigned int hdrlen = sizeof(struct udphdr) +
581 sizeof(struct gtp0_header);
582 struct gtp0_header *gtp0;
583 struct pdp_ctx *pctx;
584 __u16 inner_proto;
585
586 if (!pskb_may_pull(skb, hdrlen))
587 return -1;
588
589 gtp0 = (struct gtp0_header *)(skb->data + sizeof(struct udphdr));
590
591 if ((gtp0->flags >> 5) != GTP_V0)
592 return 1;
593
594 /* If the sockets were created in kernel, it means that
595 * there is no daemon running in userspace which would
596 * handle echo request.
597 */
598 if (gtp0->type == GTP_ECHO_REQ && gtp->sk_created)
599 return gtp0_send_echo_resp(gtp, skb);
600
601 if (gtp0->type == GTP_ECHO_RSP && gtp->sk_created)
602 return gtp0_handle_echo_resp(gtp, skb);
603
604 if (gtp0->type != GTP_TPDU)
605 return 1;
606
607 if (gtp_inner_proto(skb, hdrlen, &inner_proto) < 0) {
608 netdev_dbg(gtp->dev, "GTP packet does not encapsulate an IP packet\n");
609 return -1;
610 }
611
612 pctx = gtp0_pdp_find(gtp, be64_to_cpu(gtp0->tid),
613 gtp_proto_to_family(inner_proto));
614 if (!pctx) {
615 netdev_dbg(gtp->dev, "No PDP ctx to decap skb=%p\n", skb);
616 return 1;
617 }
618
619 return gtp_rx(pctx, skb, hdrlen, gtp->role, inner_proto);
620 }
621
622 /* msg_type has to be GTP_ECHO_REQ or GTP_ECHO_RSP */
gtp1u_build_echo_msg(struct gtp1_header_long * hdr,__u8 msg_type)623 static void gtp1u_build_echo_msg(struct gtp1_header_long *hdr, __u8 msg_type)
624 {
625 int len_pkt, len_hdr;
626
627 /* S flag must be set to 1 */
628 hdr->flags = 0x32; /* v1, GTP-non-prime. */
629 hdr->type = msg_type;
630 /* 3GPP TS 29.281 5.1 - TEID has to be set to 0 */
631 hdr->tid = 0;
632
633 /* seq, npdu and next should be counted to the length of the GTP packet
634 * that's why szie of gtp1_header should be subtracted,
635 * not size of gtp1_header_long.
636 */
637
638 len_hdr = sizeof(struct gtp1_header);
639
640 if (msg_type == GTP_ECHO_RSP) {
641 len_pkt = sizeof(struct gtp1u_packet);
642 hdr->length = htons(len_pkt - len_hdr);
643 } else {
644 /* GTP_ECHO_REQ does not carry GTP Information Element,
645 * the why gtp1_header_long is used here.
646 */
647 len_pkt = sizeof(struct gtp1_header_long);
648 hdr->length = htons(len_pkt - len_hdr);
649 }
650 }
651
gtp1u_send_echo_resp(struct gtp_dev * gtp,struct sk_buff * skb)652 static int gtp1u_send_echo_resp(struct gtp_dev *gtp, struct sk_buff *skb)
653 {
654 struct gtp1_header_long *gtp1u;
655 struct gtp1u_packet *gtp_pkt;
656 struct rtable *rt;
657 struct flowi4 fl4;
658 struct iphdr *iph;
659
660 gtp1u = (struct gtp1_header_long *)(skb->data + sizeof(struct udphdr));
661
662 /* 3GPP TS 29.281 5.1 - For the Echo Request, Echo Response,
663 * Error Indication and Supported Extension Headers Notification
664 * messages, the S flag shall be set to 1 and TEID shall be set to 0.
665 */
666 if (!(gtp1u->flags & GTP1_F_SEQ) || gtp1u->tid)
667 return -1;
668
669 /* pull GTP and UDP headers */
670 skb_pull_data(skb,
671 sizeof(struct gtp1_header_long) + sizeof(struct udphdr));
672
673 gtp_pkt = skb_push(skb, sizeof(struct gtp1u_packet));
674 memset(gtp_pkt, 0, sizeof(struct gtp1u_packet));
675
676 gtp1u_build_echo_msg(>p_pkt->gtp1u_h, GTP_ECHO_RSP);
677
678 /* 3GPP TS 29.281 7.7.2 - The Restart Counter value in the
679 * Recovery information element shall not be used, i.e. it shall
680 * be set to zero by the sender and shall be ignored by the receiver.
681 * The Recovery information element is mandatory due to backwards
682 * compatibility reasons.
683 */
684 gtp_pkt->ie.tag = GTPIE_RECOVERY;
685 gtp_pkt->ie.val = 0;
686
687 iph = ip_hdr(skb);
688
689 /* find route to the sender,
690 * src address becomes dst address and vice versa.
691 */
692 rt = ip4_route_output_gtp(&fl4, gtp->sk1u, iph->saddr, iph->daddr);
693 if (IS_ERR(rt)) {
694 netdev_dbg(gtp->dev, "no route for echo response from %pI4\n",
695 &iph->saddr);
696 return -1;
697 }
698
699 udp_tunnel_xmit_skb(rt, gtp->sk1u, skb,
700 fl4.saddr, fl4.daddr,
701 iph->tos,
702 ip4_dst_hoplimit(&rt->dst),
703 0,
704 htons(GTP1U_PORT), htons(GTP1U_PORT),
705 !net_eq(sock_net(gtp->sk1u),
706 dev_net(gtp->dev)),
707 false);
708 return 0;
709 }
710
gtp1u_handle_echo_resp(struct gtp_dev * gtp,struct sk_buff * skb)711 static int gtp1u_handle_echo_resp(struct gtp_dev *gtp, struct sk_buff *skb)
712 {
713 struct gtp1_header_long *gtp1u;
714 struct echo_info echo;
715 struct sk_buff *msg;
716 struct iphdr *iph;
717 int ret;
718
719 gtp1u = (struct gtp1_header_long *)(skb->data + sizeof(struct udphdr));
720
721 /* 3GPP TS 29.281 5.1 - For the Echo Request, Echo Response,
722 * Error Indication and Supported Extension Headers Notification
723 * messages, the S flag shall be set to 1 and TEID shall be set to 0.
724 */
725 if (!(gtp1u->flags & GTP1_F_SEQ) || gtp1u->tid)
726 return -1;
727
728 iph = ip_hdr(skb);
729 echo.ms.addr.s_addr = iph->daddr;
730 echo.peer.addr.s_addr = iph->saddr;
731 echo.gtp_version = GTP_V1;
732
733 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
734 if (!msg)
735 return -ENOMEM;
736
737 ret = gtp_genl_fill_echo(msg, 0, 0, 0, GTP_CMD_ECHOREQ, echo);
738 if (ret < 0) {
739 nlmsg_free(msg);
740 return ret;
741 }
742
743 return genlmsg_multicast_netns(>p_genl_family, dev_net(gtp->dev),
744 msg, 0, GTP_GENL_MCGRP, GFP_ATOMIC);
745 }
746
gtp_parse_exthdrs(struct sk_buff * skb,unsigned int * hdrlen)747 static int gtp_parse_exthdrs(struct sk_buff *skb, unsigned int *hdrlen)
748 {
749 struct gtp_ext_hdr *gtp_exthdr, _gtp_exthdr;
750 unsigned int offset = *hdrlen;
751 __u8 *next_type, _next_type;
752
753 /* From 29.060: "The Extension Header Length field specifies the length
754 * of the particular Extension header in 4 octets units."
755 *
756 * This length field includes length field size itself (1 byte),
757 * payload (variable length) and next type (1 byte). The extension
758 * header is aligned to to 4 bytes.
759 */
760
761 do {
762 gtp_exthdr = skb_header_pointer(skb, offset, sizeof(*gtp_exthdr),
763 &_gtp_exthdr);
764 if (!gtp_exthdr || !gtp_exthdr->len)
765 return -1;
766
767 offset += gtp_exthdr->len * 4;
768
769 /* From 29.060: "If no such Header follows, then the value of
770 * the Next Extension Header Type shall be 0."
771 */
772 next_type = skb_header_pointer(skb, offset - 1,
773 sizeof(_next_type), &_next_type);
774 if (!next_type)
775 return -1;
776
777 } while (*next_type != 0);
778
779 *hdrlen = offset;
780
781 return 0;
782 }
783
gtp1u_udp_encap_recv(struct gtp_dev * gtp,struct sk_buff * skb)784 static int gtp1u_udp_encap_recv(struct gtp_dev *gtp, struct sk_buff *skb)
785 {
786 unsigned int hdrlen = sizeof(struct udphdr) +
787 sizeof(struct gtp1_header);
788 struct gtp1_header *gtp1;
789 struct pdp_ctx *pctx;
790 __u16 inner_proto;
791
792 if (!pskb_may_pull(skb, hdrlen))
793 return -1;
794
795 gtp1 = (struct gtp1_header *)(skb->data + sizeof(struct udphdr));
796
797 if ((gtp1->flags >> 5) != GTP_V1)
798 return 1;
799
800 /* If the sockets were created in kernel, it means that
801 * there is no daemon running in userspace which would
802 * handle echo request.
803 */
804 if (gtp1->type == GTP_ECHO_REQ && gtp->sk_created)
805 return gtp1u_send_echo_resp(gtp, skb);
806
807 if (gtp1->type == GTP_ECHO_RSP && gtp->sk_created)
808 return gtp1u_handle_echo_resp(gtp, skb);
809
810 if (gtp1->type != GTP_TPDU)
811 return 1;
812
813 /* From 29.060: "This field shall be present if and only if any one or
814 * more of the S, PN and E flags are set.".
815 *
816 * If any of the bit is set, then the remaining ones also have to be
817 * set.
818 */
819 if (gtp1->flags & GTP1_F_MASK)
820 hdrlen += 4;
821
822 /* Make sure the header is larger enough, including extensions. */
823 if (!pskb_may_pull(skb, hdrlen))
824 return -1;
825
826 if (gtp_inner_proto(skb, hdrlen, &inner_proto) < 0) {
827 netdev_dbg(gtp->dev, "GTP packet does not encapsulate an IP packet\n");
828 return -1;
829 }
830
831 gtp1 = (struct gtp1_header *)(skb->data + sizeof(struct udphdr));
832
833 pctx = gtp1_pdp_find(gtp, ntohl(gtp1->tid),
834 gtp_proto_to_family(inner_proto));
835 if (!pctx) {
836 netdev_dbg(gtp->dev, "No PDP ctx to decap skb=%p\n", skb);
837 return 1;
838 }
839
840 if (gtp1->flags & GTP1_F_EXTHDR &&
841 gtp_parse_exthdrs(skb, &hdrlen) < 0)
842 return -1;
843
844 return gtp_rx(pctx, skb, hdrlen, gtp->role, inner_proto);
845 }
846
__gtp_encap_destroy(struct sock * sk)847 static void __gtp_encap_destroy(struct sock *sk)
848 {
849 struct gtp_dev *gtp;
850
851 lock_sock(sk);
852 gtp = sk->sk_user_data;
853 if (gtp) {
854 if (gtp->sk0 == sk)
855 gtp->sk0 = NULL;
856 else
857 gtp->sk1u = NULL;
858 WRITE_ONCE(udp_sk(sk)->encap_type, 0);
859 rcu_assign_sk_user_data(sk, NULL);
860 release_sock(sk);
861 sock_put(sk);
862 return;
863 }
864 release_sock(sk);
865 }
866
gtp_encap_destroy(struct sock * sk)867 static void gtp_encap_destroy(struct sock *sk)
868 {
869 rtnl_lock();
870 __gtp_encap_destroy(sk);
871 rtnl_unlock();
872 }
873
gtp_encap_disable_sock(struct sock * sk)874 static void gtp_encap_disable_sock(struct sock *sk)
875 {
876 if (!sk)
877 return;
878
879 __gtp_encap_destroy(sk);
880 }
881
gtp_encap_disable(struct gtp_dev * gtp)882 static void gtp_encap_disable(struct gtp_dev *gtp)
883 {
884 if (gtp->sk_created) {
885 udp_tunnel_sock_release(gtp->sk0->sk_socket);
886 udp_tunnel_sock_release(gtp->sk1u->sk_socket);
887 gtp->sk_created = false;
888 gtp->sk0 = NULL;
889 gtp->sk1u = NULL;
890 } else {
891 gtp_encap_disable_sock(gtp->sk0);
892 gtp_encap_disable_sock(gtp->sk1u);
893 }
894 }
895
896 /* UDP encapsulation receive handler. See net/ipv4/udp.c.
897 * Return codes: 0: success, <0: error, >0: pass up to userspace UDP socket.
898 */
gtp_encap_recv(struct sock * sk,struct sk_buff * skb)899 static int gtp_encap_recv(struct sock *sk, struct sk_buff *skb)
900 {
901 struct gtp_dev *gtp;
902 int ret = 0;
903
904 gtp = rcu_dereference_sk_user_data(sk);
905 if (!gtp)
906 return 1;
907
908 netdev_dbg(gtp->dev, "encap_recv sk=%p\n", sk);
909
910 switch (READ_ONCE(udp_sk(sk)->encap_type)) {
911 case UDP_ENCAP_GTP0:
912 netdev_dbg(gtp->dev, "received GTP0 packet\n");
913 ret = gtp0_udp_encap_recv(gtp, skb);
914 break;
915 case UDP_ENCAP_GTP1U:
916 netdev_dbg(gtp->dev, "received GTP1U packet\n");
917 ret = gtp1u_udp_encap_recv(gtp, skb);
918 break;
919 default:
920 ret = -1; /* Shouldn't happen. */
921 }
922
923 switch (ret) {
924 case 1:
925 netdev_dbg(gtp->dev, "pass up to the process\n");
926 break;
927 case 0:
928 break;
929 case -1:
930 netdev_dbg(gtp->dev, "GTP packet has been dropped\n");
931 kfree_skb(skb);
932 ret = 0;
933 break;
934 }
935
936 return ret;
937 }
938
gtp_dev_uninit(struct net_device * dev)939 static void gtp_dev_uninit(struct net_device *dev)
940 {
941 struct gtp_dev *gtp = netdev_priv(dev);
942
943 gtp_encap_disable(gtp);
944 }
945
gtp0_push_header(struct sk_buff * skb,struct pdp_ctx * pctx)946 static inline void gtp0_push_header(struct sk_buff *skb, struct pdp_ctx *pctx)
947 {
948 int payload_len = skb->len;
949 struct gtp0_header *gtp0;
950
951 gtp0 = skb_push(skb, sizeof(*gtp0));
952
953 gtp0->flags = 0x1e; /* v0, GTP-non-prime. */
954 gtp0->type = GTP_TPDU;
955 gtp0->length = htons(payload_len);
956 gtp0->seq = htons((atomic_inc_return(&pctx->tx_seq) - 1) % 0xffff);
957 gtp0->flow = htons(pctx->u.v0.flow);
958 gtp0->number = 0xff;
959 gtp0->spare[0] = gtp0->spare[1] = gtp0->spare[2] = 0xff;
960 gtp0->tid = cpu_to_be64(pctx->u.v0.tid);
961 }
962
gtp1_push_header(struct sk_buff * skb,struct pdp_ctx * pctx)963 static inline void gtp1_push_header(struct sk_buff *skb, struct pdp_ctx *pctx)
964 {
965 int payload_len = skb->len;
966 struct gtp1_header *gtp1;
967
968 gtp1 = skb_push(skb, sizeof(*gtp1));
969
970 /* Bits 8 7 6 5 4 3 2 1
971 * +--+--+--+--+--+--+--+--+
972 * |version |PT| 0| E| S|PN|
973 * +--+--+--+--+--+--+--+--+
974 * 0 0 1 1 1 0 0 0
975 */
976 gtp1->flags = 0x30; /* v1, GTP-non-prime. */
977 gtp1->type = GTP_TPDU;
978 gtp1->length = htons(payload_len);
979 gtp1->tid = htonl(pctx->u.v1.o_tei);
980
981 /* TODO: Support for extension header, sequence number and N-PDU.
982 * Update the length field if any of them is available.
983 */
984 }
985
986 struct gtp_pktinfo {
987 struct sock *sk;
988 union {
989 struct flowi4 fl4;
990 struct flowi6 fl6;
991 };
992 union {
993 struct rtable *rt;
994 struct rt6_info *rt6;
995 };
996 struct pdp_ctx *pctx;
997 struct net_device *dev;
998 __u8 tos;
999 __be16 gtph_port;
1000 };
1001
gtp_push_header(struct sk_buff * skb,struct gtp_pktinfo * pktinfo)1002 static void gtp_push_header(struct sk_buff *skb, struct gtp_pktinfo *pktinfo)
1003 {
1004 switch (pktinfo->pctx->gtp_version) {
1005 case GTP_V0:
1006 pktinfo->gtph_port = htons(GTP0_PORT);
1007 gtp0_push_header(skb, pktinfo->pctx);
1008 break;
1009 case GTP_V1:
1010 pktinfo->gtph_port = htons(GTP1U_PORT);
1011 gtp1_push_header(skb, pktinfo->pctx);
1012 break;
1013 }
1014 }
1015
gtp_set_pktinfo_ipv4(struct gtp_pktinfo * pktinfo,struct sock * sk,__u8 tos,struct pdp_ctx * pctx,struct rtable * rt,struct flowi4 * fl4,struct net_device * dev)1016 static inline void gtp_set_pktinfo_ipv4(struct gtp_pktinfo *pktinfo,
1017 struct sock *sk, __u8 tos,
1018 struct pdp_ctx *pctx, struct rtable *rt,
1019 struct flowi4 *fl4,
1020 struct net_device *dev)
1021 {
1022 pktinfo->sk = sk;
1023 pktinfo->tos = tos;
1024 pktinfo->pctx = pctx;
1025 pktinfo->rt = rt;
1026 pktinfo->fl4 = *fl4;
1027 pktinfo->dev = dev;
1028 }
1029
gtp_set_pktinfo_ipv6(struct gtp_pktinfo * pktinfo,struct sock * sk,__u8 tos,struct pdp_ctx * pctx,struct rt6_info * rt6,struct flowi6 * fl6,struct net_device * dev)1030 static void gtp_set_pktinfo_ipv6(struct gtp_pktinfo *pktinfo,
1031 struct sock *sk, __u8 tos,
1032 struct pdp_ctx *pctx, struct rt6_info *rt6,
1033 struct flowi6 *fl6,
1034 struct net_device *dev)
1035 {
1036 pktinfo->sk = sk;
1037 pktinfo->tos = tos;
1038 pktinfo->pctx = pctx;
1039 pktinfo->rt6 = rt6;
1040 pktinfo->fl6 = *fl6;
1041 pktinfo->dev = dev;
1042 }
1043
gtp_build_skb_outer_ip4(struct sk_buff * skb,struct net_device * dev,struct gtp_pktinfo * pktinfo,struct pdp_ctx * pctx,__u8 tos,__be16 frag_off)1044 static int gtp_build_skb_outer_ip4(struct sk_buff *skb, struct net_device *dev,
1045 struct gtp_pktinfo *pktinfo,
1046 struct pdp_ctx *pctx, __u8 tos,
1047 __be16 frag_off)
1048 {
1049 struct rtable *rt;
1050 struct flowi4 fl4;
1051 __be16 df;
1052 int mtu;
1053
1054 rt = ip4_route_output_gtp(&fl4, pctx->sk, pctx->peer.addr.s_addr,
1055 inet_sk(pctx->sk)->inet_saddr);
1056 if (IS_ERR(rt)) {
1057 netdev_dbg(dev, "no route to SSGN %pI4\n",
1058 &pctx->peer.addr.s_addr);
1059 dev->stats.tx_carrier_errors++;
1060 goto err;
1061 }
1062
1063 if (rt->dst.dev == dev) {
1064 netdev_dbg(dev, "circular route to SSGN %pI4\n",
1065 &pctx->peer.addr.s_addr);
1066 dev->stats.collisions++;
1067 goto err_rt;
1068 }
1069
1070 /* This is similar to tnl_update_pmtu(). */
1071 df = frag_off;
1072 if (df) {
1073 mtu = dst_mtu(&rt->dst) - dev->hard_header_len -
1074 sizeof(struct iphdr) - sizeof(struct udphdr);
1075 switch (pctx->gtp_version) {
1076 case GTP_V0:
1077 mtu -= sizeof(struct gtp0_header);
1078 break;
1079 case GTP_V1:
1080 mtu -= sizeof(struct gtp1_header);
1081 break;
1082 }
1083 } else {
1084 mtu = dst_mtu(&rt->dst);
1085 }
1086
1087 skb_dst_update_pmtu_no_confirm(skb, mtu);
1088
1089 if (frag_off & htons(IP_DF) &&
1090 ((!skb_is_gso(skb) && skb->len > mtu) ||
1091 (skb_is_gso(skb) && !skb_gso_validate_network_len(skb, mtu)))) {
1092 netdev_dbg(dev, "packet too big, fragmentation needed\n");
1093 icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
1094 htonl(mtu));
1095 goto err_rt;
1096 }
1097
1098 gtp_set_pktinfo_ipv4(pktinfo, pctx->sk, tos, pctx, rt, &fl4, dev);
1099 gtp_push_header(skb, pktinfo);
1100
1101 return 0;
1102 err_rt:
1103 ip_rt_put(rt);
1104 err:
1105 return -EBADMSG;
1106 }
1107
gtp_build_skb_outer_ip6(struct net * net,struct sk_buff * skb,struct net_device * dev,struct gtp_pktinfo * pktinfo,struct pdp_ctx * pctx,__u8 tos)1108 static int gtp_build_skb_outer_ip6(struct net *net, struct sk_buff *skb,
1109 struct net_device *dev,
1110 struct gtp_pktinfo *pktinfo,
1111 struct pdp_ctx *pctx, __u8 tos)
1112 {
1113 struct dst_entry *dst;
1114 struct rt6_info *rt;
1115 struct flowi6 fl6;
1116 int mtu;
1117
1118 rt = ip6_route_output_gtp(net, &fl6, pctx->sk, &pctx->peer.addr6,
1119 &inet6_sk(pctx->sk)->saddr);
1120 if (IS_ERR(rt)) {
1121 netdev_dbg(dev, "no route to SSGN %pI6\n",
1122 &pctx->peer.addr6);
1123 dev->stats.tx_carrier_errors++;
1124 goto err;
1125 }
1126 dst = &rt->dst;
1127
1128 if (rt->dst.dev == dev) {
1129 netdev_dbg(dev, "circular route to SSGN %pI6\n",
1130 &pctx->peer.addr6);
1131 dev->stats.collisions++;
1132 goto err_rt;
1133 }
1134
1135 mtu = dst_mtu(&rt->dst) - dev->hard_header_len -
1136 sizeof(struct ipv6hdr) - sizeof(struct udphdr);
1137 switch (pctx->gtp_version) {
1138 case GTP_V0:
1139 mtu -= sizeof(struct gtp0_header);
1140 break;
1141 case GTP_V1:
1142 mtu -= sizeof(struct gtp1_header);
1143 break;
1144 }
1145
1146 skb_dst_update_pmtu_no_confirm(skb, mtu);
1147
1148 if ((!skb_is_gso(skb) && skb->len > mtu) ||
1149 (skb_is_gso(skb) && !skb_gso_validate_network_len(skb, mtu))) {
1150 netdev_dbg(dev, "packet too big, fragmentation needed\n");
1151 icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
1152 goto err_rt;
1153 }
1154
1155 gtp_set_pktinfo_ipv6(pktinfo, pctx->sk, tos, pctx, rt, &fl6, dev);
1156 gtp_push_header(skb, pktinfo);
1157
1158 return 0;
1159 err_rt:
1160 dst_release(dst);
1161 err:
1162 return -EBADMSG;
1163 }
1164
gtp_build_skb_ip4(struct sk_buff * skb,struct net_device * dev,struct gtp_pktinfo * pktinfo)1165 static int gtp_build_skb_ip4(struct sk_buff *skb, struct net_device *dev,
1166 struct gtp_pktinfo *pktinfo)
1167 {
1168 struct gtp_dev *gtp = netdev_priv(dev);
1169 struct net *net = gtp->net;
1170 struct pdp_ctx *pctx;
1171 struct iphdr *iph;
1172 int ret;
1173
1174 /* Read the IP destination address and resolve the PDP context.
1175 * Prepend PDP header with TEI/TID from PDP ctx.
1176 */
1177 iph = ip_hdr(skb);
1178 if (gtp->role == GTP_ROLE_SGSN)
1179 pctx = ipv4_pdp_find(gtp, iph->saddr);
1180 else
1181 pctx = ipv4_pdp_find(gtp, iph->daddr);
1182
1183 if (!pctx) {
1184 netdev_dbg(dev, "no PDP ctx found for %pI4, skip\n",
1185 &iph->daddr);
1186 return -ENOENT;
1187 }
1188 netdev_dbg(dev, "found PDP context %p\n", pctx);
1189
1190 switch (pctx->sk->sk_family) {
1191 case AF_INET:
1192 ret = gtp_build_skb_outer_ip4(skb, dev, pktinfo, pctx,
1193 iph->tos, iph->frag_off);
1194 break;
1195 case AF_INET6:
1196 ret = gtp_build_skb_outer_ip6(net, skb, dev, pktinfo, pctx,
1197 iph->tos);
1198 break;
1199 default:
1200 ret = -1;
1201 WARN_ON_ONCE(1);
1202 break;
1203 }
1204
1205 if (ret < 0)
1206 return ret;
1207
1208 netdev_dbg(dev, "gtp -> IP src: %pI4 dst: %pI4\n",
1209 &iph->saddr, &iph->daddr);
1210
1211 return 0;
1212 }
1213
gtp_build_skb_ip6(struct sk_buff * skb,struct net_device * dev,struct gtp_pktinfo * pktinfo)1214 static int gtp_build_skb_ip6(struct sk_buff *skb, struct net_device *dev,
1215 struct gtp_pktinfo *pktinfo)
1216 {
1217 struct gtp_dev *gtp = netdev_priv(dev);
1218 struct net *net = gtp->net;
1219 struct pdp_ctx *pctx;
1220 struct ipv6hdr *ip6h;
1221 __u8 tos;
1222 int ret;
1223
1224 /* Read the IP destination address and resolve the PDP context.
1225 * Prepend PDP header with TEI/TID from PDP ctx.
1226 */
1227 ip6h = ipv6_hdr(skb);
1228 if (gtp->role == GTP_ROLE_SGSN)
1229 pctx = ipv6_pdp_find(gtp, &ip6h->saddr);
1230 else
1231 pctx = ipv6_pdp_find(gtp, &ip6h->daddr);
1232
1233 if (!pctx) {
1234 netdev_dbg(dev, "no PDP ctx found for %pI6, skip\n",
1235 &ip6h->daddr);
1236 return -ENOENT;
1237 }
1238 netdev_dbg(dev, "found PDP context %p\n", pctx);
1239
1240 tos = ipv6_get_dsfield(ip6h);
1241
1242 switch (pctx->sk->sk_family) {
1243 case AF_INET:
1244 ret = gtp_build_skb_outer_ip4(skb, dev, pktinfo, pctx, tos, 0);
1245 break;
1246 case AF_INET6:
1247 ret = gtp_build_skb_outer_ip6(net, skb, dev, pktinfo, pctx, tos);
1248 break;
1249 default:
1250 ret = -1;
1251 WARN_ON_ONCE(1);
1252 break;
1253 }
1254
1255 if (ret < 0)
1256 return ret;
1257
1258 netdev_dbg(dev, "gtp -> IP src: %pI6 dst: %pI6\n",
1259 &ip6h->saddr, &ip6h->daddr);
1260
1261 return 0;
1262 }
1263
gtp_dev_xmit(struct sk_buff * skb,struct net_device * dev)1264 static netdev_tx_t gtp_dev_xmit(struct sk_buff *skb, struct net_device *dev)
1265 {
1266 unsigned int proto = ntohs(skb->protocol);
1267 struct gtp_pktinfo pktinfo;
1268 int err;
1269
1270 /* Ensure there is sufficient headroom. */
1271 if (skb_cow_head(skb, dev->needed_headroom))
1272 goto tx_err;
1273
1274 if (!pskb_inet_may_pull(skb))
1275 goto tx_err;
1276
1277 skb_reset_inner_headers(skb);
1278
1279 /* PDP context lookups in gtp_build_skb_*() need rcu read-side lock. */
1280 rcu_read_lock();
1281 switch (proto) {
1282 case ETH_P_IP:
1283 err = gtp_build_skb_ip4(skb, dev, &pktinfo);
1284 break;
1285 case ETH_P_IPV6:
1286 err = gtp_build_skb_ip6(skb, dev, &pktinfo);
1287 break;
1288 default:
1289 err = -EOPNOTSUPP;
1290 break;
1291 }
1292 rcu_read_unlock();
1293
1294 if (err < 0)
1295 goto tx_err;
1296
1297 switch (pktinfo.pctx->sk->sk_family) {
1298 case AF_INET:
1299 udp_tunnel_xmit_skb(pktinfo.rt, pktinfo.sk, skb,
1300 pktinfo.fl4.saddr, pktinfo.fl4.daddr,
1301 pktinfo.tos,
1302 ip4_dst_hoplimit(&pktinfo.rt->dst),
1303 0,
1304 pktinfo.gtph_port, pktinfo.gtph_port,
1305 !net_eq(sock_net(pktinfo.pctx->sk),
1306 dev_net(dev)),
1307 false);
1308 break;
1309 case AF_INET6:
1310 #if IS_ENABLED(CONFIG_IPV6)
1311 udp_tunnel6_xmit_skb(&pktinfo.rt6->dst, pktinfo.sk, skb, dev,
1312 &pktinfo.fl6.saddr, &pktinfo.fl6.daddr,
1313 pktinfo.tos,
1314 ip6_dst_hoplimit(&pktinfo.rt->dst),
1315 0,
1316 pktinfo.gtph_port, pktinfo.gtph_port,
1317 false);
1318 #else
1319 goto tx_err;
1320 #endif
1321 break;
1322 }
1323
1324 return NETDEV_TX_OK;
1325 tx_err:
1326 dev->stats.tx_errors++;
1327 dev_kfree_skb(skb);
1328 return NETDEV_TX_OK;
1329 }
1330
1331 static const struct net_device_ops gtp_netdev_ops = {
1332 .ndo_uninit = gtp_dev_uninit,
1333 .ndo_start_xmit = gtp_dev_xmit,
1334 };
1335
1336 static const struct device_type gtp_type = {
1337 .name = "gtp",
1338 };
1339
1340 #define GTP_TH_MAXLEN (sizeof(struct udphdr) + sizeof(struct gtp0_header))
1341 #define GTP_IPV4_MAXLEN (sizeof(struct iphdr) + GTP_TH_MAXLEN)
1342
gtp_link_setup(struct net_device * dev)1343 static void gtp_link_setup(struct net_device *dev)
1344 {
1345 struct gtp_dev *gtp = netdev_priv(dev);
1346
1347 dev->netdev_ops = >p_netdev_ops;
1348 dev->needs_free_netdev = true;
1349 SET_NETDEV_DEVTYPE(dev, >p_type);
1350
1351 dev->hard_header_len = 0;
1352 dev->addr_len = 0;
1353 dev->mtu = ETH_DATA_LEN - GTP_IPV4_MAXLEN;
1354
1355 /* Zero header length. */
1356 dev->type = ARPHRD_NONE;
1357 dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
1358
1359 dev->pcpu_stat_type = NETDEV_PCPU_STAT_TSTATS;
1360 dev->priv_flags |= IFF_NO_QUEUE;
1361 dev->lltx = true;
1362 netif_keep_dst(dev);
1363
1364 dev->needed_headroom = LL_MAX_HEADER + GTP_IPV4_MAXLEN;
1365 gtp->dev = dev;
1366 }
1367
1368 static int gtp_hashtable_new(struct gtp_dev *gtp, int hsize);
1369 static int gtp_encap_enable(struct gtp_dev *gtp, struct nlattr *data[]);
1370
gtp_destructor(struct net_device * dev)1371 static void gtp_destructor(struct net_device *dev)
1372 {
1373 struct gtp_dev *gtp = netdev_priv(dev);
1374
1375 kfree(gtp->addr_hash);
1376 kfree(gtp->tid_hash);
1377 }
1378
gtp_sock_udp_config(struct udp_port_cfg * udp_conf,const struct nlattr * nla,int family)1379 static int gtp_sock_udp_config(struct udp_port_cfg *udp_conf,
1380 const struct nlattr *nla, int family)
1381 {
1382 udp_conf->family = family;
1383
1384 switch (udp_conf->family) {
1385 case AF_INET:
1386 udp_conf->local_ip.s_addr = nla_get_be32(nla);
1387 break;
1388 #if IS_ENABLED(CONFIG_IPV6)
1389 case AF_INET6:
1390 udp_conf->local_ip6 = nla_get_in6_addr(nla);
1391 break;
1392 #endif
1393 default:
1394 return -EOPNOTSUPP;
1395 }
1396
1397 return 0;
1398 }
1399
gtp_create_sock(int type,struct gtp_dev * gtp,const struct nlattr * nla,int family)1400 static struct sock *gtp_create_sock(int type, struct gtp_dev *gtp,
1401 const struct nlattr *nla, int family)
1402 {
1403 struct udp_tunnel_sock_cfg tuncfg = {};
1404 struct udp_port_cfg udp_conf = {};
1405 struct net *net = gtp->net;
1406 struct socket *sock;
1407 int err;
1408
1409 if (nla) {
1410 err = gtp_sock_udp_config(&udp_conf, nla, family);
1411 if (err < 0)
1412 return ERR_PTR(err);
1413 } else {
1414 udp_conf.local_ip.s_addr = htonl(INADDR_ANY);
1415 udp_conf.family = AF_INET;
1416 }
1417
1418 if (type == UDP_ENCAP_GTP0)
1419 udp_conf.local_udp_port = htons(GTP0_PORT);
1420 else if (type == UDP_ENCAP_GTP1U)
1421 udp_conf.local_udp_port = htons(GTP1U_PORT);
1422 else
1423 return ERR_PTR(-EINVAL);
1424
1425 err = udp_sock_create(net, &udp_conf, &sock);
1426 if (err)
1427 return ERR_PTR(err);
1428
1429 tuncfg.sk_user_data = gtp;
1430 tuncfg.encap_type = type;
1431 tuncfg.encap_rcv = gtp_encap_recv;
1432 tuncfg.encap_destroy = NULL;
1433
1434 setup_udp_tunnel_sock(net, sock, &tuncfg);
1435
1436 return sock->sk;
1437 }
1438
gtp_create_sockets(struct gtp_dev * gtp,const struct nlattr * nla,int family)1439 static int gtp_create_sockets(struct gtp_dev *gtp, const struct nlattr *nla,
1440 int family)
1441 {
1442 struct sock *sk1u;
1443 struct sock *sk0;
1444
1445 sk0 = gtp_create_sock(UDP_ENCAP_GTP0, gtp, nla, family);
1446 if (IS_ERR(sk0))
1447 return PTR_ERR(sk0);
1448
1449 sk1u = gtp_create_sock(UDP_ENCAP_GTP1U, gtp, nla, family);
1450 if (IS_ERR(sk1u)) {
1451 udp_tunnel_sock_release(sk0->sk_socket);
1452 return PTR_ERR(sk1u);
1453 }
1454
1455 gtp->sk_created = true;
1456 gtp->sk0 = sk0;
1457 gtp->sk1u = sk1u;
1458
1459 return 0;
1460 }
1461
1462 #define GTP_TH_MAXLEN (sizeof(struct udphdr) + sizeof(struct gtp0_header))
1463 #define GTP_IPV6_MAXLEN (sizeof(struct ipv6hdr) + GTP_TH_MAXLEN)
1464
gtp_newlink(struct net * src_net,struct net_device * dev,struct nlattr * tb[],struct nlattr * data[],struct netlink_ext_ack * extack)1465 static int gtp_newlink(struct net *src_net, struct net_device *dev,
1466 struct nlattr *tb[], struct nlattr *data[],
1467 struct netlink_ext_ack *extack)
1468 {
1469 unsigned int role = GTP_ROLE_GGSN;
1470 struct gtp_dev *gtp;
1471 struct gtp_net *gn;
1472 int hashsize, err;
1473
1474 #if !IS_ENABLED(CONFIG_IPV6)
1475 if (data[IFLA_GTP_LOCAL6])
1476 return -EAFNOSUPPORT;
1477 #endif
1478
1479 gtp = netdev_priv(dev);
1480
1481 if (!data[IFLA_GTP_PDP_HASHSIZE]) {
1482 hashsize = 1024;
1483 } else {
1484 hashsize = nla_get_u32(data[IFLA_GTP_PDP_HASHSIZE]);
1485 if (!hashsize)
1486 hashsize = 1024;
1487 }
1488
1489 if (data[IFLA_GTP_ROLE]) {
1490 role = nla_get_u32(data[IFLA_GTP_ROLE]);
1491 if (role > GTP_ROLE_SGSN)
1492 return -EINVAL;
1493 }
1494 gtp->role = role;
1495
1496 gtp->restart_count = nla_get_u8_default(data[IFLA_GTP_RESTART_COUNT],
1497 0);
1498
1499 gtp->net = src_net;
1500
1501 err = gtp_hashtable_new(gtp, hashsize);
1502 if (err < 0)
1503 return err;
1504
1505 if (data[IFLA_GTP_CREATE_SOCKETS]) {
1506 if (data[IFLA_GTP_LOCAL6])
1507 err = gtp_create_sockets(gtp, data[IFLA_GTP_LOCAL6], AF_INET6);
1508 else
1509 err = gtp_create_sockets(gtp, data[IFLA_GTP_LOCAL], AF_INET);
1510 } else {
1511 err = gtp_encap_enable(gtp, data);
1512 }
1513
1514 if (err < 0)
1515 goto out_hashtable;
1516
1517 if ((gtp->sk0 && gtp->sk0->sk_family == AF_INET6) ||
1518 (gtp->sk1u && gtp->sk1u->sk_family == AF_INET6)) {
1519 dev->mtu = ETH_DATA_LEN - GTP_IPV6_MAXLEN;
1520 dev->needed_headroom = LL_MAX_HEADER + GTP_IPV6_MAXLEN;
1521 }
1522
1523 err = register_netdevice(dev);
1524 if (err < 0) {
1525 netdev_dbg(dev, "failed to register new netdev %d\n", err);
1526 goto out_encap;
1527 }
1528
1529 gn = net_generic(src_net, gtp_net_id);
1530 list_add(>p->list, &gn->gtp_dev_list);
1531 dev->priv_destructor = gtp_destructor;
1532
1533 netdev_dbg(dev, "registered new GTP interface\n");
1534
1535 return 0;
1536
1537 out_encap:
1538 gtp_encap_disable(gtp);
1539 out_hashtable:
1540 kfree(gtp->addr_hash);
1541 kfree(gtp->tid_hash);
1542 return err;
1543 }
1544
gtp_dellink(struct net_device * dev,struct list_head * head)1545 static void gtp_dellink(struct net_device *dev, struct list_head *head)
1546 {
1547 struct gtp_dev *gtp = netdev_priv(dev);
1548 struct hlist_node *next;
1549 struct pdp_ctx *pctx;
1550 int i;
1551
1552 for (i = 0; i < gtp->hash_size; i++)
1553 hlist_for_each_entry_safe(pctx, next, >p->tid_hash[i], hlist_tid)
1554 pdp_context_delete(pctx);
1555
1556 list_del(>p->list);
1557 unregister_netdevice_queue(dev, head);
1558 }
1559
1560 static const struct nla_policy gtp_policy[IFLA_GTP_MAX + 1] = {
1561 [IFLA_GTP_FD0] = { .type = NLA_U32 },
1562 [IFLA_GTP_FD1] = { .type = NLA_U32 },
1563 [IFLA_GTP_PDP_HASHSIZE] = { .type = NLA_U32 },
1564 [IFLA_GTP_ROLE] = { .type = NLA_U32 },
1565 [IFLA_GTP_CREATE_SOCKETS] = { .type = NLA_U8 },
1566 [IFLA_GTP_RESTART_COUNT] = { .type = NLA_U8 },
1567 [IFLA_GTP_LOCAL] = { .type = NLA_U32 },
1568 [IFLA_GTP_LOCAL6] = { .len = sizeof(struct in6_addr) },
1569 };
1570
gtp_validate(struct nlattr * tb[],struct nlattr * data[],struct netlink_ext_ack * extack)1571 static int gtp_validate(struct nlattr *tb[], struct nlattr *data[],
1572 struct netlink_ext_ack *extack)
1573 {
1574 if (!data)
1575 return -EINVAL;
1576
1577 return 0;
1578 }
1579
gtp_get_size(const struct net_device * dev)1580 static size_t gtp_get_size(const struct net_device *dev)
1581 {
1582 return nla_total_size(sizeof(__u32)) + /* IFLA_GTP_PDP_HASHSIZE */
1583 nla_total_size(sizeof(__u32)) + /* IFLA_GTP_ROLE */
1584 nla_total_size(sizeof(__u8)); /* IFLA_GTP_RESTART_COUNT */
1585 }
1586
gtp_fill_info(struct sk_buff * skb,const struct net_device * dev)1587 static int gtp_fill_info(struct sk_buff *skb, const struct net_device *dev)
1588 {
1589 struct gtp_dev *gtp = netdev_priv(dev);
1590
1591 if (nla_put_u32(skb, IFLA_GTP_PDP_HASHSIZE, gtp->hash_size))
1592 goto nla_put_failure;
1593 if (nla_put_u32(skb, IFLA_GTP_ROLE, gtp->role))
1594 goto nla_put_failure;
1595 if (nla_put_u8(skb, IFLA_GTP_RESTART_COUNT, gtp->restart_count))
1596 goto nla_put_failure;
1597
1598 return 0;
1599
1600 nla_put_failure:
1601 return -EMSGSIZE;
1602 }
1603
1604 static struct rtnl_link_ops gtp_link_ops __read_mostly = {
1605 .kind = "gtp",
1606 .maxtype = IFLA_GTP_MAX,
1607 .policy = gtp_policy,
1608 .priv_size = sizeof(struct gtp_dev),
1609 .setup = gtp_link_setup,
1610 .validate = gtp_validate,
1611 .newlink = gtp_newlink,
1612 .dellink = gtp_dellink,
1613 .get_size = gtp_get_size,
1614 .fill_info = gtp_fill_info,
1615 };
1616
gtp_hashtable_new(struct gtp_dev * gtp,int hsize)1617 static int gtp_hashtable_new(struct gtp_dev *gtp, int hsize)
1618 {
1619 int i;
1620
1621 gtp->addr_hash = kmalloc_array(hsize, sizeof(struct hlist_head),
1622 GFP_KERNEL | __GFP_NOWARN);
1623 if (gtp->addr_hash == NULL)
1624 return -ENOMEM;
1625
1626 gtp->tid_hash = kmalloc_array(hsize, sizeof(struct hlist_head),
1627 GFP_KERNEL | __GFP_NOWARN);
1628 if (gtp->tid_hash == NULL)
1629 goto err1;
1630
1631 gtp->hash_size = hsize;
1632
1633 for (i = 0; i < hsize; i++) {
1634 INIT_HLIST_HEAD(>p->addr_hash[i]);
1635 INIT_HLIST_HEAD(>p->tid_hash[i]);
1636 }
1637 return 0;
1638 err1:
1639 kfree(gtp->addr_hash);
1640 return -ENOMEM;
1641 }
1642
gtp_encap_enable_socket(int fd,int type,struct gtp_dev * gtp)1643 static struct sock *gtp_encap_enable_socket(int fd, int type,
1644 struct gtp_dev *gtp)
1645 {
1646 struct udp_tunnel_sock_cfg tuncfg = {NULL};
1647 struct socket *sock;
1648 struct sock *sk;
1649 int err;
1650
1651 pr_debug("enable gtp on %d, %d\n", fd, type);
1652
1653 sock = sockfd_lookup(fd, &err);
1654 if (!sock) {
1655 pr_debug("gtp socket fd=%d not found\n", fd);
1656 return ERR_PTR(err);
1657 }
1658
1659 sk = sock->sk;
1660 if (sk->sk_protocol != IPPROTO_UDP ||
1661 sk->sk_type != SOCK_DGRAM ||
1662 (sk->sk_family != AF_INET && sk->sk_family != AF_INET6)) {
1663 pr_debug("socket fd=%d not UDP\n", fd);
1664 sk = ERR_PTR(-EINVAL);
1665 goto out_sock;
1666 }
1667
1668 if (sk->sk_family == AF_INET6 &&
1669 !sk->sk_ipv6only) {
1670 sk = ERR_PTR(-EADDRNOTAVAIL);
1671 goto out_sock;
1672 }
1673
1674 lock_sock(sk);
1675 if (sk->sk_user_data) {
1676 sk = ERR_PTR(-EBUSY);
1677 goto out_rel_sock;
1678 }
1679
1680 sock_hold(sk);
1681
1682 tuncfg.sk_user_data = gtp;
1683 tuncfg.encap_type = type;
1684 tuncfg.encap_rcv = gtp_encap_recv;
1685 tuncfg.encap_destroy = gtp_encap_destroy;
1686
1687 setup_udp_tunnel_sock(sock_net(sock->sk), sock, &tuncfg);
1688
1689 out_rel_sock:
1690 release_sock(sock->sk);
1691 out_sock:
1692 sockfd_put(sock);
1693 return sk;
1694 }
1695
gtp_encap_enable(struct gtp_dev * gtp,struct nlattr * data[])1696 static int gtp_encap_enable(struct gtp_dev *gtp, struct nlattr *data[])
1697 {
1698 struct sock *sk1u = NULL;
1699 struct sock *sk0 = NULL;
1700
1701 if (!data[IFLA_GTP_FD0] && !data[IFLA_GTP_FD1])
1702 return -EINVAL;
1703
1704 if (data[IFLA_GTP_FD0]) {
1705 int fd0 = nla_get_u32(data[IFLA_GTP_FD0]);
1706
1707 if (fd0 >= 0) {
1708 sk0 = gtp_encap_enable_socket(fd0, UDP_ENCAP_GTP0, gtp);
1709 if (IS_ERR(sk0))
1710 return PTR_ERR(sk0);
1711 }
1712 }
1713
1714 if (data[IFLA_GTP_FD1]) {
1715 int fd1 = nla_get_u32(data[IFLA_GTP_FD1]);
1716
1717 if (fd1 >= 0) {
1718 sk1u = gtp_encap_enable_socket(fd1, UDP_ENCAP_GTP1U, gtp);
1719 if (IS_ERR(sk1u)) {
1720 gtp_encap_disable_sock(sk0);
1721 return PTR_ERR(sk1u);
1722 }
1723 }
1724 }
1725
1726 gtp->sk0 = sk0;
1727 gtp->sk1u = sk1u;
1728
1729 if (sk0 && sk1u &&
1730 sk0->sk_family != sk1u->sk_family) {
1731 gtp_encap_disable_sock(sk0);
1732 gtp_encap_disable_sock(sk1u);
1733 return -EINVAL;
1734 }
1735
1736 return 0;
1737 }
1738
gtp_find_dev(struct net * src_net,struct nlattr * nla[])1739 static struct gtp_dev *gtp_find_dev(struct net *src_net, struct nlattr *nla[])
1740 {
1741 struct gtp_dev *gtp = NULL;
1742 struct net_device *dev;
1743 struct net *net;
1744
1745 /* Examine the link attributes and figure out which network namespace
1746 * we are talking about.
1747 */
1748 if (nla[GTPA_NET_NS_FD])
1749 net = get_net_ns_by_fd(nla_get_u32(nla[GTPA_NET_NS_FD]));
1750 else
1751 net = get_net(src_net);
1752
1753 if (IS_ERR(net))
1754 return NULL;
1755
1756 /* Check if there's an existing gtpX device to configure */
1757 dev = dev_get_by_index_rcu(net, nla_get_u32(nla[GTPA_LINK]));
1758 if (dev && dev->netdev_ops == >p_netdev_ops)
1759 gtp = netdev_priv(dev);
1760
1761 put_net(net);
1762 return gtp;
1763 }
1764
gtp_pdp_fill(struct pdp_ctx * pctx,struct genl_info * info)1765 static void gtp_pdp_fill(struct pdp_ctx *pctx, struct genl_info *info)
1766 {
1767 pctx->gtp_version = nla_get_u32(info->attrs[GTPA_VERSION]);
1768
1769 switch (pctx->gtp_version) {
1770 case GTP_V0:
1771 /* According to TS 09.60, sections 7.5.1 and 7.5.2, the flow
1772 * label needs to be the same for uplink and downlink packets,
1773 * so let's annotate this.
1774 */
1775 pctx->u.v0.tid = nla_get_u64(info->attrs[GTPA_TID]);
1776 pctx->u.v0.flow = nla_get_u16(info->attrs[GTPA_FLOW]);
1777 break;
1778 case GTP_V1:
1779 pctx->u.v1.i_tei = nla_get_u32(info->attrs[GTPA_I_TEI]);
1780 pctx->u.v1.o_tei = nla_get_u32(info->attrs[GTPA_O_TEI]);
1781 break;
1782 default:
1783 break;
1784 }
1785 }
1786
ip_pdp_peer_fill(struct pdp_ctx * pctx,struct genl_info * info)1787 static void ip_pdp_peer_fill(struct pdp_ctx *pctx, struct genl_info *info)
1788 {
1789 if (info->attrs[GTPA_PEER_ADDRESS]) {
1790 pctx->peer.addr.s_addr =
1791 nla_get_be32(info->attrs[GTPA_PEER_ADDRESS]);
1792 } else if (info->attrs[GTPA_PEER_ADDR6]) {
1793 pctx->peer.addr6 = nla_get_in6_addr(info->attrs[GTPA_PEER_ADDR6]);
1794 }
1795 }
1796
ipv4_pdp_fill(struct pdp_ctx * pctx,struct genl_info * info)1797 static void ipv4_pdp_fill(struct pdp_ctx *pctx, struct genl_info *info)
1798 {
1799 ip_pdp_peer_fill(pctx, info);
1800 pctx->ms.addr.s_addr =
1801 nla_get_be32(info->attrs[GTPA_MS_ADDRESS]);
1802 gtp_pdp_fill(pctx, info);
1803 }
1804
ipv6_pdp_fill(struct pdp_ctx * pctx,struct genl_info * info)1805 static bool ipv6_pdp_fill(struct pdp_ctx *pctx, struct genl_info *info)
1806 {
1807 ip_pdp_peer_fill(pctx, info);
1808 pctx->ms.addr6 = nla_get_in6_addr(info->attrs[GTPA_MS_ADDR6]);
1809 if (pctx->ms.addr6.s6_addr32[2] ||
1810 pctx->ms.addr6.s6_addr32[3])
1811 return false;
1812
1813 gtp_pdp_fill(pctx, info);
1814
1815 return true;
1816 }
1817
gtp_pdp_add(struct gtp_dev * gtp,struct sock * sk,struct genl_info * info)1818 static struct pdp_ctx *gtp_pdp_add(struct gtp_dev *gtp, struct sock *sk,
1819 struct genl_info *info)
1820 {
1821 struct pdp_ctx *pctx, *pctx_tid = NULL;
1822 struct net_device *dev = gtp->dev;
1823 u32 hash_ms, hash_tid = 0;
1824 struct in6_addr ms_addr6;
1825 unsigned int version;
1826 bool found = false;
1827 __be32 ms_addr;
1828 int family;
1829
1830 version = nla_get_u32(info->attrs[GTPA_VERSION]);
1831
1832 family = nla_get_u8_default(info->attrs[GTPA_FAMILY], AF_INET);
1833
1834 #if !IS_ENABLED(CONFIG_IPV6)
1835 if (family == AF_INET6)
1836 return ERR_PTR(-EAFNOSUPPORT);
1837 #endif
1838 if (!info->attrs[GTPA_PEER_ADDRESS] &&
1839 !info->attrs[GTPA_PEER_ADDR6])
1840 return ERR_PTR(-EINVAL);
1841
1842 if ((info->attrs[GTPA_PEER_ADDRESS] &&
1843 sk->sk_family == AF_INET6) ||
1844 (info->attrs[GTPA_PEER_ADDR6] &&
1845 sk->sk_family == AF_INET))
1846 return ERR_PTR(-EAFNOSUPPORT);
1847
1848 switch (family) {
1849 case AF_INET:
1850 if (!info->attrs[GTPA_MS_ADDRESS] ||
1851 info->attrs[GTPA_MS_ADDR6])
1852 return ERR_PTR(-EINVAL);
1853
1854 ms_addr = nla_get_be32(info->attrs[GTPA_MS_ADDRESS]);
1855 hash_ms = ipv4_hashfn(ms_addr) % gtp->hash_size;
1856 pctx = ipv4_pdp_find(gtp, ms_addr);
1857 break;
1858 case AF_INET6:
1859 if (!info->attrs[GTPA_MS_ADDR6] ||
1860 info->attrs[GTPA_MS_ADDRESS])
1861 return ERR_PTR(-EINVAL);
1862
1863 ms_addr6 = nla_get_in6_addr(info->attrs[GTPA_MS_ADDR6]);
1864 hash_ms = ipv6_hashfn(&ms_addr6) % gtp->hash_size;
1865 pctx = ipv6_pdp_find(gtp, &ms_addr6);
1866 break;
1867 default:
1868 return ERR_PTR(-EAFNOSUPPORT);
1869 }
1870 if (pctx)
1871 found = true;
1872 if (version == GTP_V0)
1873 pctx_tid = gtp0_pdp_find(gtp,
1874 nla_get_u64(info->attrs[GTPA_TID]),
1875 family);
1876 else if (version == GTP_V1)
1877 pctx_tid = gtp1_pdp_find(gtp,
1878 nla_get_u32(info->attrs[GTPA_I_TEI]),
1879 family);
1880 if (pctx_tid)
1881 found = true;
1882
1883 if (found) {
1884 if (info->nlhdr->nlmsg_flags & NLM_F_EXCL)
1885 return ERR_PTR(-EEXIST);
1886 if (info->nlhdr->nlmsg_flags & NLM_F_REPLACE)
1887 return ERR_PTR(-EOPNOTSUPP);
1888
1889 if (pctx && pctx_tid)
1890 return ERR_PTR(-EEXIST);
1891 if (!pctx)
1892 pctx = pctx_tid;
1893
1894 switch (pctx->af) {
1895 case AF_INET:
1896 ipv4_pdp_fill(pctx, info);
1897 break;
1898 case AF_INET6:
1899 if (!ipv6_pdp_fill(pctx, info))
1900 return ERR_PTR(-EADDRNOTAVAIL);
1901 break;
1902 }
1903
1904 if (pctx->gtp_version == GTP_V0)
1905 netdev_dbg(dev, "GTPv0-U: update tunnel id = %llx (pdp %p)\n",
1906 pctx->u.v0.tid, pctx);
1907 else if (pctx->gtp_version == GTP_V1)
1908 netdev_dbg(dev, "GTPv1-U: update tunnel id = %x/%x (pdp %p)\n",
1909 pctx->u.v1.i_tei, pctx->u.v1.o_tei, pctx);
1910
1911 return pctx;
1912
1913 }
1914
1915 pctx = kmalloc(sizeof(*pctx), GFP_ATOMIC);
1916 if (pctx == NULL)
1917 return ERR_PTR(-ENOMEM);
1918
1919 sock_hold(sk);
1920 pctx->sk = sk;
1921 pctx->dev = gtp->dev;
1922 pctx->af = family;
1923
1924 switch (pctx->af) {
1925 case AF_INET:
1926 if (!info->attrs[GTPA_MS_ADDRESS]) {
1927 sock_put(sk);
1928 kfree(pctx);
1929 return ERR_PTR(-EINVAL);
1930 }
1931
1932 ipv4_pdp_fill(pctx, info);
1933 break;
1934 case AF_INET6:
1935 if (!info->attrs[GTPA_MS_ADDR6]) {
1936 sock_put(sk);
1937 kfree(pctx);
1938 return ERR_PTR(-EINVAL);
1939 }
1940
1941 if (!ipv6_pdp_fill(pctx, info)) {
1942 sock_put(sk);
1943 kfree(pctx);
1944 return ERR_PTR(-EADDRNOTAVAIL);
1945 }
1946 break;
1947 }
1948 atomic_set(&pctx->tx_seq, 0);
1949
1950 switch (pctx->gtp_version) {
1951 case GTP_V0:
1952 /* TS 09.60: "The flow label identifies unambiguously a GTP
1953 * flow.". We use the tid for this instead, I cannot find a
1954 * situation in which this doesn't unambiguosly identify the
1955 * PDP context.
1956 */
1957 hash_tid = gtp0_hashfn(pctx->u.v0.tid) % gtp->hash_size;
1958 break;
1959 case GTP_V1:
1960 hash_tid = gtp1u_hashfn(pctx->u.v1.i_tei) % gtp->hash_size;
1961 break;
1962 }
1963
1964 hlist_add_head_rcu(&pctx->hlist_addr, >p->addr_hash[hash_ms]);
1965 hlist_add_head_rcu(&pctx->hlist_tid, >p->tid_hash[hash_tid]);
1966
1967 switch (pctx->gtp_version) {
1968 case GTP_V0:
1969 netdev_dbg(dev, "GTPv0-U: new PDP ctx id=%llx ssgn=%pI4 ms=%pI4 (pdp=%p)\n",
1970 pctx->u.v0.tid, &pctx->peer.addr,
1971 &pctx->ms.addr, pctx);
1972 break;
1973 case GTP_V1:
1974 netdev_dbg(dev, "GTPv1-U: new PDP ctx id=%x/%x ssgn=%pI4 ms=%pI4 (pdp=%p)\n",
1975 pctx->u.v1.i_tei, pctx->u.v1.o_tei,
1976 &pctx->peer.addr, &pctx->ms.addr, pctx);
1977 break;
1978 }
1979
1980 return pctx;
1981 }
1982
pdp_context_free(struct rcu_head * head)1983 static void pdp_context_free(struct rcu_head *head)
1984 {
1985 struct pdp_ctx *pctx = container_of(head, struct pdp_ctx, rcu_head);
1986
1987 sock_put(pctx->sk);
1988 kfree(pctx);
1989 }
1990
pdp_context_delete(struct pdp_ctx * pctx)1991 static void pdp_context_delete(struct pdp_ctx *pctx)
1992 {
1993 hlist_del_rcu(&pctx->hlist_tid);
1994 hlist_del_rcu(&pctx->hlist_addr);
1995 call_rcu(&pctx->rcu_head, pdp_context_free);
1996 }
1997
1998 static int gtp_tunnel_notify(struct pdp_ctx *pctx, u8 cmd, gfp_t allocation);
1999
gtp_genl_new_pdp(struct sk_buff * skb,struct genl_info * info)2000 static int gtp_genl_new_pdp(struct sk_buff *skb, struct genl_info *info)
2001 {
2002 unsigned int version;
2003 struct pdp_ctx *pctx;
2004 struct gtp_dev *gtp;
2005 struct sock *sk;
2006 int err;
2007
2008 if (!info->attrs[GTPA_VERSION] ||
2009 !info->attrs[GTPA_LINK])
2010 return -EINVAL;
2011
2012 version = nla_get_u32(info->attrs[GTPA_VERSION]);
2013
2014 switch (version) {
2015 case GTP_V0:
2016 if (!info->attrs[GTPA_TID] ||
2017 !info->attrs[GTPA_FLOW])
2018 return -EINVAL;
2019 break;
2020 case GTP_V1:
2021 if (!info->attrs[GTPA_I_TEI] ||
2022 !info->attrs[GTPA_O_TEI])
2023 return -EINVAL;
2024 break;
2025
2026 default:
2027 return -EINVAL;
2028 }
2029
2030 rtnl_lock();
2031
2032 gtp = gtp_find_dev(sock_net(skb->sk), info->attrs);
2033 if (!gtp) {
2034 err = -ENODEV;
2035 goto out_unlock;
2036 }
2037
2038 if (version == GTP_V0)
2039 sk = gtp->sk0;
2040 else if (version == GTP_V1)
2041 sk = gtp->sk1u;
2042 else
2043 sk = NULL;
2044
2045 if (!sk) {
2046 err = -ENODEV;
2047 goto out_unlock;
2048 }
2049
2050 pctx = gtp_pdp_add(gtp, sk, info);
2051 if (IS_ERR(pctx)) {
2052 err = PTR_ERR(pctx);
2053 } else {
2054 gtp_tunnel_notify(pctx, GTP_CMD_NEWPDP, GFP_KERNEL);
2055 err = 0;
2056 }
2057
2058 out_unlock:
2059 rtnl_unlock();
2060 return err;
2061 }
2062
gtp_find_pdp_by_link(struct net * net,struct nlattr * nla[])2063 static struct pdp_ctx *gtp_find_pdp_by_link(struct net *net,
2064 struct nlattr *nla[])
2065 {
2066 struct gtp_dev *gtp;
2067 int family;
2068
2069 family = nla_get_u8_default(nla[GTPA_FAMILY], AF_INET);
2070
2071 gtp = gtp_find_dev(net, nla);
2072 if (!gtp)
2073 return ERR_PTR(-ENODEV);
2074
2075 if (nla[GTPA_MS_ADDRESS]) {
2076 __be32 ip = nla_get_be32(nla[GTPA_MS_ADDRESS]);
2077
2078 if (family != AF_INET)
2079 return ERR_PTR(-EINVAL);
2080
2081 return ipv4_pdp_find(gtp, ip);
2082 } else if (nla[GTPA_MS_ADDR6]) {
2083 struct in6_addr addr = nla_get_in6_addr(nla[GTPA_MS_ADDR6]);
2084
2085 if (family != AF_INET6)
2086 return ERR_PTR(-EINVAL);
2087
2088 if (addr.s6_addr32[2] ||
2089 addr.s6_addr32[3])
2090 return ERR_PTR(-EADDRNOTAVAIL);
2091
2092 return ipv6_pdp_find(gtp, &addr);
2093 } else if (nla[GTPA_VERSION]) {
2094 u32 gtp_version = nla_get_u32(nla[GTPA_VERSION]);
2095
2096 if (gtp_version == GTP_V0 && nla[GTPA_TID]) {
2097 return gtp0_pdp_find(gtp, nla_get_u64(nla[GTPA_TID]),
2098 family);
2099 } else if (gtp_version == GTP_V1 && nla[GTPA_I_TEI]) {
2100 return gtp1_pdp_find(gtp, nla_get_u32(nla[GTPA_I_TEI]),
2101 family);
2102 }
2103 }
2104
2105 return ERR_PTR(-EINVAL);
2106 }
2107
gtp_find_pdp(struct net * net,struct nlattr * nla[])2108 static struct pdp_ctx *gtp_find_pdp(struct net *net, struct nlattr *nla[])
2109 {
2110 struct pdp_ctx *pctx;
2111
2112 if (nla[GTPA_LINK])
2113 pctx = gtp_find_pdp_by_link(net, nla);
2114 else
2115 pctx = ERR_PTR(-EINVAL);
2116
2117 if (!pctx)
2118 pctx = ERR_PTR(-ENOENT);
2119
2120 return pctx;
2121 }
2122
gtp_genl_del_pdp(struct sk_buff * skb,struct genl_info * info)2123 static int gtp_genl_del_pdp(struct sk_buff *skb, struct genl_info *info)
2124 {
2125 struct pdp_ctx *pctx;
2126 int err = 0;
2127
2128 if (!info->attrs[GTPA_VERSION])
2129 return -EINVAL;
2130
2131 rcu_read_lock();
2132
2133 pctx = gtp_find_pdp(sock_net(skb->sk), info->attrs);
2134 if (IS_ERR(pctx)) {
2135 err = PTR_ERR(pctx);
2136 goto out_unlock;
2137 }
2138
2139 if (pctx->gtp_version == GTP_V0)
2140 netdev_dbg(pctx->dev, "GTPv0-U: deleting tunnel id = %llx (pdp %p)\n",
2141 pctx->u.v0.tid, pctx);
2142 else if (pctx->gtp_version == GTP_V1)
2143 netdev_dbg(pctx->dev, "GTPv1-U: deleting tunnel id = %x/%x (pdp %p)\n",
2144 pctx->u.v1.i_tei, pctx->u.v1.o_tei, pctx);
2145
2146 gtp_tunnel_notify(pctx, GTP_CMD_DELPDP, GFP_ATOMIC);
2147 pdp_context_delete(pctx);
2148
2149 out_unlock:
2150 rcu_read_unlock();
2151 return err;
2152 }
2153
gtp_genl_fill_info(struct sk_buff * skb,u32 snd_portid,u32 snd_seq,int flags,u32 type,struct pdp_ctx * pctx)2154 static int gtp_genl_fill_info(struct sk_buff *skb, u32 snd_portid, u32 snd_seq,
2155 int flags, u32 type, struct pdp_ctx *pctx)
2156 {
2157 void *genlh;
2158
2159 genlh = genlmsg_put(skb, snd_portid, snd_seq, >p_genl_family, flags,
2160 type);
2161 if (genlh == NULL)
2162 goto nlmsg_failure;
2163
2164 if (nla_put_u32(skb, GTPA_VERSION, pctx->gtp_version) ||
2165 nla_put_u32(skb, GTPA_LINK, pctx->dev->ifindex) ||
2166 nla_put_u8(skb, GTPA_FAMILY, pctx->af))
2167 goto nla_put_failure;
2168
2169 switch (pctx->af) {
2170 case AF_INET:
2171 if (nla_put_be32(skb, GTPA_MS_ADDRESS, pctx->ms.addr.s_addr))
2172 goto nla_put_failure;
2173 break;
2174 case AF_INET6:
2175 if (nla_put_in6_addr(skb, GTPA_MS_ADDR6, &pctx->ms.addr6))
2176 goto nla_put_failure;
2177 break;
2178 }
2179
2180 switch (pctx->sk->sk_family) {
2181 case AF_INET:
2182 if (nla_put_be32(skb, GTPA_PEER_ADDRESS, pctx->peer.addr.s_addr))
2183 goto nla_put_failure;
2184 break;
2185 case AF_INET6:
2186 if (nla_put_in6_addr(skb, GTPA_PEER_ADDR6, &pctx->peer.addr6))
2187 goto nla_put_failure;
2188 break;
2189 }
2190
2191 switch (pctx->gtp_version) {
2192 case GTP_V0:
2193 if (nla_put_u64_64bit(skb, GTPA_TID, pctx->u.v0.tid, GTPA_PAD) ||
2194 nla_put_u16(skb, GTPA_FLOW, pctx->u.v0.flow))
2195 goto nla_put_failure;
2196 break;
2197 case GTP_V1:
2198 if (nla_put_u32(skb, GTPA_I_TEI, pctx->u.v1.i_tei) ||
2199 nla_put_u32(skb, GTPA_O_TEI, pctx->u.v1.o_tei))
2200 goto nla_put_failure;
2201 break;
2202 }
2203 genlmsg_end(skb, genlh);
2204 return 0;
2205
2206 nlmsg_failure:
2207 nla_put_failure:
2208 genlmsg_cancel(skb, genlh);
2209 return -EMSGSIZE;
2210 }
2211
gtp_tunnel_notify(struct pdp_ctx * pctx,u8 cmd,gfp_t allocation)2212 static int gtp_tunnel_notify(struct pdp_ctx *pctx, u8 cmd, gfp_t allocation)
2213 {
2214 struct sk_buff *msg;
2215 int ret;
2216
2217 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, allocation);
2218 if (!msg)
2219 return -ENOMEM;
2220
2221 ret = gtp_genl_fill_info(msg, 0, 0, 0, cmd, pctx);
2222 if (ret < 0) {
2223 nlmsg_free(msg);
2224 return ret;
2225 }
2226
2227 ret = genlmsg_multicast_netns(>p_genl_family, dev_net(pctx->dev), msg,
2228 0, GTP_GENL_MCGRP, GFP_ATOMIC);
2229 return ret;
2230 }
2231
gtp_genl_get_pdp(struct sk_buff * skb,struct genl_info * info)2232 static int gtp_genl_get_pdp(struct sk_buff *skb, struct genl_info *info)
2233 {
2234 struct pdp_ctx *pctx = NULL;
2235 struct sk_buff *skb2;
2236 int err;
2237
2238 if (!info->attrs[GTPA_VERSION])
2239 return -EINVAL;
2240
2241 rcu_read_lock();
2242
2243 pctx = gtp_find_pdp(sock_net(skb->sk), info->attrs);
2244 if (IS_ERR(pctx)) {
2245 err = PTR_ERR(pctx);
2246 goto err_unlock;
2247 }
2248
2249 skb2 = genlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC);
2250 if (skb2 == NULL) {
2251 err = -ENOMEM;
2252 goto err_unlock;
2253 }
2254
2255 err = gtp_genl_fill_info(skb2, NETLINK_CB(skb).portid, info->snd_seq,
2256 0, info->nlhdr->nlmsg_type, pctx);
2257 if (err < 0)
2258 goto err_unlock_free;
2259
2260 rcu_read_unlock();
2261 return genlmsg_unicast(genl_info_net(info), skb2, info->snd_portid);
2262
2263 err_unlock_free:
2264 kfree_skb(skb2);
2265 err_unlock:
2266 rcu_read_unlock();
2267 return err;
2268 }
2269
gtp_genl_dump_pdp(struct sk_buff * skb,struct netlink_callback * cb)2270 static int gtp_genl_dump_pdp(struct sk_buff *skb,
2271 struct netlink_callback *cb)
2272 {
2273 struct gtp_dev *last_gtp = (struct gtp_dev *)cb->args[2], *gtp;
2274 int i, j, bucket = cb->args[0], skip = cb->args[1];
2275 struct net *net = sock_net(skb->sk);
2276 struct net_device *dev;
2277 struct pdp_ctx *pctx;
2278
2279 if (cb->args[4])
2280 return 0;
2281
2282 rcu_read_lock();
2283 for_each_netdev_rcu(net, dev) {
2284 if (dev->rtnl_link_ops != >p_link_ops)
2285 continue;
2286
2287 gtp = netdev_priv(dev);
2288
2289 if (last_gtp && last_gtp != gtp)
2290 continue;
2291 else
2292 last_gtp = NULL;
2293
2294 for (i = bucket; i < gtp->hash_size; i++) {
2295 j = 0;
2296 hlist_for_each_entry_rcu(pctx, >p->tid_hash[i],
2297 hlist_tid) {
2298 if (j >= skip &&
2299 gtp_genl_fill_info(skb,
2300 NETLINK_CB(cb->skb).portid,
2301 cb->nlh->nlmsg_seq,
2302 NLM_F_MULTI,
2303 cb->nlh->nlmsg_type, pctx)) {
2304 cb->args[0] = i;
2305 cb->args[1] = j;
2306 cb->args[2] = (unsigned long)gtp;
2307 goto out;
2308 }
2309 j++;
2310 }
2311 skip = 0;
2312 }
2313 bucket = 0;
2314 }
2315 cb->args[4] = 1;
2316 out:
2317 rcu_read_unlock();
2318 return skb->len;
2319 }
2320
gtp_genl_send_echo_req(struct sk_buff * skb,struct genl_info * info)2321 static int gtp_genl_send_echo_req(struct sk_buff *skb, struct genl_info *info)
2322 {
2323 struct sk_buff *skb_to_send;
2324 __be32 src_ip, dst_ip;
2325 unsigned int version;
2326 struct gtp_dev *gtp;
2327 struct flowi4 fl4;
2328 struct rtable *rt;
2329 struct sock *sk;
2330 __be16 port;
2331 int len;
2332
2333 if (!info->attrs[GTPA_VERSION] ||
2334 !info->attrs[GTPA_LINK] ||
2335 !info->attrs[GTPA_PEER_ADDRESS] ||
2336 !info->attrs[GTPA_MS_ADDRESS])
2337 return -EINVAL;
2338
2339 version = nla_get_u32(info->attrs[GTPA_VERSION]);
2340 dst_ip = nla_get_be32(info->attrs[GTPA_PEER_ADDRESS]);
2341 src_ip = nla_get_be32(info->attrs[GTPA_MS_ADDRESS]);
2342
2343 gtp = gtp_find_dev(sock_net(skb->sk), info->attrs);
2344 if (!gtp)
2345 return -ENODEV;
2346
2347 if (!gtp->sk_created)
2348 return -EOPNOTSUPP;
2349 if (!(gtp->dev->flags & IFF_UP))
2350 return -ENETDOWN;
2351
2352 if (version == GTP_V0) {
2353 struct gtp0_header *gtp0_h;
2354
2355 len = LL_RESERVED_SPACE(gtp->dev) + sizeof(struct gtp0_header) +
2356 sizeof(struct iphdr) + sizeof(struct udphdr);
2357
2358 skb_to_send = netdev_alloc_skb_ip_align(gtp->dev, len);
2359 if (!skb_to_send)
2360 return -ENOMEM;
2361
2362 sk = gtp->sk0;
2363 port = htons(GTP0_PORT);
2364
2365 gtp0_h = skb_push(skb_to_send, sizeof(struct gtp0_header));
2366 memset(gtp0_h, 0, sizeof(struct gtp0_header));
2367 gtp0_build_echo_msg(gtp0_h, GTP_ECHO_REQ);
2368 } else if (version == GTP_V1) {
2369 struct gtp1_header_long *gtp1u_h;
2370
2371 len = LL_RESERVED_SPACE(gtp->dev) +
2372 sizeof(struct gtp1_header_long) +
2373 sizeof(struct iphdr) + sizeof(struct udphdr);
2374
2375 skb_to_send = netdev_alloc_skb_ip_align(gtp->dev, len);
2376 if (!skb_to_send)
2377 return -ENOMEM;
2378
2379 sk = gtp->sk1u;
2380 port = htons(GTP1U_PORT);
2381
2382 gtp1u_h = skb_push(skb_to_send,
2383 sizeof(struct gtp1_header_long));
2384 memset(gtp1u_h, 0, sizeof(struct gtp1_header_long));
2385 gtp1u_build_echo_msg(gtp1u_h, GTP_ECHO_REQ);
2386 } else {
2387 return -ENODEV;
2388 }
2389
2390 rt = ip4_route_output_gtp(&fl4, sk, dst_ip, src_ip);
2391 if (IS_ERR(rt)) {
2392 netdev_dbg(gtp->dev, "no route for echo request to %pI4\n",
2393 &dst_ip);
2394 kfree_skb(skb_to_send);
2395 return -ENODEV;
2396 }
2397
2398 udp_tunnel_xmit_skb(rt, sk, skb_to_send,
2399 fl4.saddr, fl4.daddr,
2400 fl4.flowi4_tos,
2401 ip4_dst_hoplimit(&rt->dst),
2402 0,
2403 port, port,
2404 !net_eq(sock_net(sk),
2405 dev_net(gtp->dev)),
2406 false);
2407 return 0;
2408 }
2409
2410 static const struct nla_policy gtp_genl_policy[GTPA_MAX + 1] = {
2411 [GTPA_LINK] = { .type = NLA_U32, },
2412 [GTPA_VERSION] = { .type = NLA_U32, },
2413 [GTPA_TID] = { .type = NLA_U64, },
2414 [GTPA_PEER_ADDRESS] = { .type = NLA_U32, },
2415 [GTPA_MS_ADDRESS] = { .type = NLA_U32, },
2416 [GTPA_FLOW] = { .type = NLA_U16, },
2417 [GTPA_NET_NS_FD] = { .type = NLA_U32, },
2418 [GTPA_I_TEI] = { .type = NLA_U32, },
2419 [GTPA_O_TEI] = { .type = NLA_U32, },
2420 [GTPA_PEER_ADDR6] = { .len = sizeof(struct in6_addr), },
2421 [GTPA_MS_ADDR6] = { .len = sizeof(struct in6_addr), },
2422 [GTPA_FAMILY] = { .type = NLA_U8, },
2423 };
2424
2425 static const struct genl_small_ops gtp_genl_ops[] = {
2426 {
2427 .cmd = GTP_CMD_NEWPDP,
2428 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
2429 .doit = gtp_genl_new_pdp,
2430 .flags = GENL_ADMIN_PERM,
2431 },
2432 {
2433 .cmd = GTP_CMD_DELPDP,
2434 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
2435 .doit = gtp_genl_del_pdp,
2436 .flags = GENL_ADMIN_PERM,
2437 },
2438 {
2439 .cmd = GTP_CMD_GETPDP,
2440 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
2441 .doit = gtp_genl_get_pdp,
2442 .dumpit = gtp_genl_dump_pdp,
2443 .flags = GENL_ADMIN_PERM,
2444 },
2445 {
2446 .cmd = GTP_CMD_ECHOREQ,
2447 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
2448 .doit = gtp_genl_send_echo_req,
2449 .flags = GENL_ADMIN_PERM,
2450 },
2451 };
2452
2453 static struct genl_family gtp_genl_family __ro_after_init = {
2454 .name = "gtp",
2455 .version = 0,
2456 .hdrsize = 0,
2457 .maxattr = GTPA_MAX,
2458 .policy = gtp_genl_policy,
2459 .netnsok = true,
2460 .module = THIS_MODULE,
2461 .small_ops = gtp_genl_ops,
2462 .n_small_ops = ARRAY_SIZE(gtp_genl_ops),
2463 .resv_start_op = GTP_CMD_ECHOREQ + 1,
2464 .mcgrps = gtp_genl_mcgrps,
2465 .n_mcgrps = ARRAY_SIZE(gtp_genl_mcgrps),
2466 };
2467
gtp_net_init(struct net * net)2468 static int __net_init gtp_net_init(struct net *net)
2469 {
2470 struct gtp_net *gn = net_generic(net, gtp_net_id);
2471
2472 INIT_LIST_HEAD(&gn->gtp_dev_list);
2473 return 0;
2474 }
2475
gtp_net_exit_batch_rtnl(struct list_head * net_list,struct list_head * dev_to_kill)2476 static void __net_exit gtp_net_exit_batch_rtnl(struct list_head *net_list,
2477 struct list_head *dev_to_kill)
2478 {
2479 struct net *net;
2480
2481 list_for_each_entry(net, net_list, exit_list) {
2482 struct gtp_net *gn = net_generic(net, gtp_net_id);
2483 struct gtp_dev *gtp, *gtp_next;
2484 struct net_device *dev;
2485
2486 for_each_netdev(net, dev)
2487 if (dev->rtnl_link_ops == >p_link_ops)
2488 gtp_dellink(dev, dev_to_kill);
2489
2490 list_for_each_entry_safe(gtp, gtp_next, &gn->gtp_dev_list, list)
2491 gtp_dellink(gtp->dev, dev_to_kill);
2492 }
2493 }
2494
2495 static struct pernet_operations gtp_net_ops = {
2496 .init = gtp_net_init,
2497 .exit_batch_rtnl = gtp_net_exit_batch_rtnl,
2498 .id = >p_net_id,
2499 .size = sizeof(struct gtp_net),
2500 };
2501
gtp_init(void)2502 static int __init gtp_init(void)
2503 {
2504 int err;
2505
2506 get_random_bytes(>p_h_initval, sizeof(gtp_h_initval));
2507
2508 err = register_pernet_subsys(>p_net_ops);
2509 if (err < 0)
2510 goto error_out;
2511
2512 err = rtnl_link_register(>p_link_ops);
2513 if (err < 0)
2514 goto unreg_pernet_subsys;
2515
2516 err = genl_register_family(>p_genl_family);
2517 if (err < 0)
2518 goto unreg_rtnl_link;
2519
2520 pr_info("GTP module loaded (pdp ctx size %zd bytes)\n",
2521 sizeof(struct pdp_ctx));
2522 return 0;
2523
2524 unreg_rtnl_link:
2525 rtnl_link_unregister(>p_link_ops);
2526 unreg_pernet_subsys:
2527 unregister_pernet_subsys(>p_net_ops);
2528 error_out:
2529 pr_err("error loading GTP module loaded\n");
2530 return err;
2531 }
2532 late_initcall(gtp_init);
2533
gtp_fini(void)2534 static void __exit gtp_fini(void)
2535 {
2536 genl_unregister_family(>p_genl_family);
2537 rtnl_link_unregister(>p_link_ops);
2538 unregister_pernet_subsys(>p_net_ops);
2539
2540 pr_info("GTP module unloaded\n");
2541 }
2542 module_exit(gtp_fini);
2543
2544 MODULE_LICENSE("GPL");
2545 MODULE_AUTHOR("Harald Welte <hwelte@sysmocom.de>");
2546 MODULE_DESCRIPTION("Interface driver for GTP encapsulated traffic");
2547 MODULE_ALIAS_RTNL_LINK("gtp");
2548 MODULE_ALIAS_GENL_FAMILY("gtp");
2549