projects / linux-2.6-block.git / blame
? search:
summary | shortlog | log | commit | commitdiff | tree
blob | blame (incremental) | history | HEAD
Merge tag 'bcachefs-2024-05-24' of https://evilpiepirate.org/git/bcachefs
[linux-2.6-block.git] / drivers / net / gtp.c
CommitLineData
2874c5fd 1// SPDX-License-Identifier: GPL-2.0-or-later
459aa660
PN		 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>
459aa660
PN		 10 */
11
12#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
13
14#include <linux/module.h>
459aa660
PN		 15#include <linux/skbuff.h>
16#include <linux/udp.h>
17#include <linux/rculist.h>
18#include <linux/jhash.h>
19#include <linux/if_tunnel.h>
20#include <linux/net.h>
21#include <linux/file.h>
22#include <linux/gtp.h>
23
24#include <net/net_namespace.h>
25#include <net/protocol.h>
26#include <net/ip.h>
999cb275 27#include <net/ipv6.h>
459aa660
PN		 28#include <net/udp.h>
29#include <net/udp_tunnel.h>
30#include <net/icmp.h>
31#include <net/xfrm.h>
32#include <net/genetlink.h>
33#include <net/netns/generic.h>
34#include <net/gtp.h>
35
36/* An active session for the subscriber. */
37struct pdp_ctx {
38 struct hlist_node hlist_tid;
39 struct hlist_node hlist_addr;
40
41 union {
459aa660
PN		 42 struct {
43 u64 tid;
44 u16 flow;
45 } v0;
46 struct {
47 u32 i_tei;
48 u32 o_tei;
49 } v1;
50 } u;
51 u8 gtp_version;
52 u16 af;
53
750771d0
PNA		 54 union {
55 struct in_addr addr;
999cb275 56 struct in6_addr addr6;
750771d0
PNA		 57 } ms;
58 union {
59 struct in_addr addr;
999cb275 60 struct in6_addr addr6;
750771d0 61 } peer;
459aa660 62
101cfbc1 63 struct sock *sk;
5b171f9c
AS		 64 struct net_device *dev;
65
459aa660
PN		 66 atomic_t tx_seq;
67 struct rcu_head rcu_head;
68};
69
70/* One instance of the GTP device. */
71struct gtp_dev {
72 struct list_head list;
73
17886c47
AS		 74 struct sock *sk0;
75 struct sock *sk1u;
b20dc3c6 76 u8 sk_created;
459aa660 77
459aa660 78 struct net_device *dev;
b20dc3c6 79 struct net *net;
459aa660 80
91ed81f9 81 unsigned int role;
459aa660
PN		 82 unsigned int hash_size;
83 struct hlist_head *tid_hash;
84 struct hlist_head *addr_hash;
9af41cc3
WD		 85
86 u8 restart_count;
459aa660
PN		 87};
88
d33bd757 89struct echo_info {
750771d0 90 u16 af;
d33bd757 91 u8 gtp_version;
750771d0
PNA		 92
93 union {
94 struct in_addr addr;
95 } ms;
96 union {
97 struct in_addr addr;
98 } peer;
d33bd757
WD		 99};
100
c7d03a00 101static unsigned int gtp_net_id __read_mostly;
459aa660
PN		 102
103struct gtp_net {
104 struct list_head gtp_dev_list;
105};
106
107static u32 gtp_h_initval;
108
d33bd757
WD		 109static struct genl_family gtp_genl_family;
110
111enum gtp_multicast_groups {
112 GTP_GENL_MCGRP,
113};
114
115static const struct genl_multicast_group gtp_genl_mcgrps[] = {
116 [GTP_GENL_MCGRP] = { .name = GTP_GENL_MCGRP_NAME },
117};
118
6b5e2e74
AS		 119static void pdp_context_delete(struct pdp_ctx *pctx);
120
459aa660
PN		 121static inline u32 gtp0_hashfn(u64 tid)
122{
123 u32 *tid32 = (u32 *) &tid;
124 return jhash_2words(tid32[0], tid32[1], gtp_h_initval);
125}
126
127static inline u32 gtp1u_hashfn(u32 tid)
128{
129 return jhash_1word(tid, gtp_h_initval);
130}
131
132static inline u32 ipv4_hashfn(__be32 ip)
133{
134 return jhash_1word((__force u32)ip, gtp_h_initval);
135}
136
999cb275
PNA		 137static u32 ipv6_hashfn(const struct in6_addr *ip6)
138{
c6461ec9
PNA		 139 return jhash_2words((__force u32)ip6->s6_addr32[0],
140 (__force u32)ip6->s6_addr32[1], gtp_h_initval);
999cb275
PNA		 141}
142
459aa660 143/* Resolve a PDP context structure based on the 64bit TID. */
c75fc0b9 144static struct pdp_ctx *gtp0_pdp_find(struct gtp_dev *gtp, u64 tid, u16 family)
459aa660
PN		 145{
146 struct hlist_head *head;
147 struct pdp_ctx *pdp;
148
149 head = &gtp->tid_hash[gtp0_hashfn(tid) % gtp->hash_size];
150
151 hlist_for_each_entry_rcu(pdp, head, hlist_tid) {
c75fc0b9
PNA		 152 if (pdp->af == family &&
153 pdp->gtp_version == GTP_V0 &&
459aa660
PN		 154 pdp->u.v0.tid == tid)
155 return pdp;
156 }
157 return NULL;
158}
159
160/* Resolve a PDP context structure based on the 32bit TEI. */
c75fc0b9 161static struct pdp_ctx *gtp1_pdp_find(struct gtp_dev *gtp, u32 tid, u16 family)
459aa660
PN		 162{
163 struct hlist_head *head;
164 struct pdp_ctx *pdp;
165
166 head = &gtp->tid_hash[gtp1u_hashfn(tid) % gtp->hash_size];
167
168 hlist_for_each_entry_rcu(pdp, head, hlist_tid) {
c75fc0b9
PNA		 169 if (pdp->af == family &&
170 pdp->gtp_version == GTP_V1 &&
459aa660
PN		 171 pdp->u.v1.i_tei == tid)
172 return pdp;
173 }
174 return NULL;
175}
176
177/* Resolve a PDP context based on IPv4 address of MS. */
178static struct pdp_ctx *ipv4_pdp_find(struct gtp_dev *gtp, __be32 ms_addr)
179{
180 struct hlist_head *head;
181 struct pdp_ctx *pdp;
182
183 head = &gtp->addr_hash[ipv4_hashfn(ms_addr) % gtp->hash_size];
184
185 hlist_for_each_entry_rcu(pdp, head, hlist_addr) {
186 if (pdp->af == AF_INET &&
750771d0 187 pdp->ms.addr.s_addr == ms_addr)
459aa660
PN		 188 return pdp;
189 }
190
191 return NULL;
192}
193
c6461ec9
PNA		 194/* 3GPP TS 29.060: PDN Connection: the association between a MS represented by
195 * [...] one IPv6 *prefix* and a PDN represented by an APN.
196 *
197 * Then, 3GPP TS 29.061, Section 11.2.1.3 says: The size of the prefix shall be
198 * according to the maximum prefix length for a global IPv6 address as
199 * specified in the IPv6 Addressing Architecture, see RFC 4291.
200 *
201 * Finally, RFC 4291 section 2.5.4 states: All Global Unicast addresses other
202 * than those that start with binary 000 have a 64-bit interface ID field
203 * (i.e., n + m = 64).
204 */
205static bool ipv6_pdp_addr_equal(const struct in6_addr *a,
206 const struct in6_addr *b)
207{
208 return a->s6_addr32[0] == b->s6_addr32[0] &&
209 a->s6_addr32[1] == b->s6_addr32[1];
210}
211
999cb275
PNA		 212static struct pdp_ctx *ipv6_pdp_find(struct gtp_dev *gtp,
213 const struct in6_addr *ms_addr)
214{
215 struct hlist_head *head;
216 struct pdp_ctx *pdp;
217
218 head = &gtp->addr_hash[ipv6_hashfn(ms_addr) % gtp->hash_size];
219
220 hlist_for_each_entry_rcu(pdp, head, hlist_addr) {
221 if (pdp->af == AF_INET6 &&
c6461ec9 222 ipv6_pdp_addr_equal(&pdp->ms.addr6, ms_addr))
999cb275
PNA		 223 return pdp;
224 }
225
226 return NULL;
227}
228
91ed81f9
JB		 229static bool gtp_check_ms_ipv4(struct sk_buff *skb, struct pdp_ctx *pctx,
230 unsigned int hdrlen, unsigned int role)
459aa660
PN		 231{
232 struct iphdr *iph;
233
234 if (!pskb_may_pull(skb, hdrlen + sizeof(struct iphdr)))
235 return false;
236
88edf103 237 iph = (struct iphdr *)(skb->data + hdrlen);
459aa660 238
91ed81f9 239 if (role == GTP_ROLE_SGSN)
750771d0 240 return iph->daddr == pctx->ms.addr.s_addr;
91ed81f9 241 else
750771d0 242 return iph->saddr == pctx->ms.addr.s_addr;
459aa660
PN		 243}
244
999cb275
PNA		 245static bool gtp_check_ms_ipv6(struct sk_buff *skb, struct pdp_ctx *pctx,
246 unsigned int hdrlen, unsigned int role)
247{
248 struct ipv6hdr *ip6h;
249 int ret;
250
251 if (!pskb_may_pull(skb, hdrlen + sizeof(struct ipv6hdr)))
252 return false;
253
254 ip6h = (struct ipv6hdr *)(skb->data + hdrlen);
255
e4f88f73
PNA		 256 if ((ipv6_addr_type(&ip6h->saddr) & IPV6_ADDR_LINKLOCAL) ||
257 (ipv6_addr_type(&ip6h->daddr) & IPV6_ADDR_LINKLOCAL))
258 return false;
259
999cb275 260 if (role == GTP_ROLE_SGSN) {
c6461ec9 261 ret = ipv6_pdp_addr_equal(&ip6h->daddr, &pctx->ms.addr6);
999cb275 262 } else {
c6461ec9 263 ret = ipv6_pdp_addr_equal(&ip6h->saddr, &pctx->ms.addr6);
999cb275
PNA		 264 }
265
c6461ec9 266 return ret;
999cb275
PNA		 267}
268
91ed81f9 269/* Check if the inner IP address in this packet is assigned to any
459aa660
PN		 270 * existing mobile subscriber.
271 */
91ed81f9 272static bool gtp_check_ms(struct sk_buff *skb, struct pdp_ctx *pctx,
e30ea48b
PNA		 273 unsigned int hdrlen, unsigned int role,
274 __u16 inner_proto)
459aa660 275{
e30ea48b 276 switch (inner_proto) {
459aa660 277 case ETH_P_IP:
91ed81f9 278 return gtp_check_ms_ipv4(skb, pctx, hdrlen, role);
999cb275
PNA		 279 case ETH_P_IPV6:
280 return gtp_check_ms_ipv6(skb, pctx, hdrlen, role);
459aa660
PN		 281 }
282 return false;
283}
284
e30ea48b
PNA		 285static int gtp_inner_proto(struct sk_buff *skb, unsigned int hdrlen,
286 __u16 *inner_proto)
287{
288 __u8 *ip_version, _ip_version;
289
290 ip_version = skb_header_pointer(skb, hdrlen, sizeof(*ip_version),
291 &_ip_version);
292 if (!ip_version)
293 return -1;
294
295 switch (*ip_version & 0xf0) {
296 case 0x40:
297 *inner_proto = ETH_P_IP;
298 break;
299 case 0x60:
300 *inner_proto = ETH_P_IPV6;
301 break;
302 default:
303 return -1;
304 }
305
306 return 0;
307}
308
49ecc587 309static int gtp_rx(struct pdp_ctx *pctx, struct sk_buff *skb,
c75fc0b9 310 unsigned int hdrlen, unsigned int role, __u16 inner_proto)
5b171f9c 311{
e30ea48b 312 if (!gtp_check_ms(skb, pctx, hdrlen, role, inner_proto)) {
49ecc587
JB		 313 netdev_dbg(pctx->dev, "No PDP ctx for this MS\n");
314 return 1;
5b171f9c
AS		 315 }
316
317 /* Get rid of the GTP + UDP headers. */
e30ea48b 318 if (iptunnel_pull_header(skb, hdrlen, htons(inner_proto),
9716178a
JB		 319 !net_eq(sock_net(pctx->sk), dev_net(pctx->dev)))) {
320 pctx->dev->stats.rx_length_errors++;
321 goto err;
322 }
9ab7e76a 323
49ecc587 324 netdev_dbg(pctx->dev, "forwarding packet from GGSN to uplink\n");
5b171f9c
AS		 325
326 /* Now that the UDP and the GTP header have been removed, set up the
327 * new network header. This is required by the upper layer to
328 * calculate the transport header.
329 */
330 skb_reset_network_header(skb);
b2d898c8 331 skb_reset_mac_header(skb);
5b171f9c 332
49ecc587
JB		 333 skb->dev = pctx->dev;
334
335 dev_sw_netstats_rx_add(pctx->dev, skb->len);
336
baebdf48 337 __netif_rx(skb);
5b171f9c 338 return 0;
9716178a
JB		 339
340err:
341 pctx->dev->stats.rx_dropped++;
342 return -1;
5b171f9c
AS		 343}
344
9af41cc3
WD		 345static struct rtable *ip4_route_output_gtp(struct flowi4 *fl4,
346 const struct sock *sk,
347 __be32 daddr, __be32 saddr)
348{
349 memset(fl4, 0, sizeof(*fl4));
350 fl4->flowi4_oif = sk->sk_bound_dev_if;
351 fl4->daddr = daddr;
352 fl4->saddr = saddr;
b16b5047
GN		 353 fl4->flowi4_tos = ip_sock_rt_tos(sk);
354 fl4->flowi4_scope = ip_sock_rt_scope(sk);
9af41cc3
WD		 355 fl4->flowi4_proto = sk->sk_protocol;
356
357 return ip_route_output_key(sock_net(sk), fl4);
358}
359
999cb275
PNA		 360static struct rt6_info *ip6_route_output_gtp(struct net *net,
361 struct flowi6 *fl6,
362 const struct sock *sk,
363 const struct in6_addr *daddr,
364 struct in6_addr *saddr)
365{
366 struct dst_entry *dst;
367
368 memset(fl6, 0, sizeof(*fl6));
369 fl6->flowi6_oif = sk->sk_bound_dev_if;
370 fl6->daddr = *daddr;
371 fl6->saddr = *saddr;
372 fl6->flowi6_proto = sk->sk_protocol;
373
374 dst = ipv6_stub->ipv6_dst_lookup_flow(net, sk, fl6, NULL);
375 if (IS_ERR(dst))
376 return ERR_PTR(-ENETUNREACH);
377
378 return (struct rt6_info *)dst;
379}
380
9af41cc3
WD		 381/* GSM TS 09.60. 7.3
382 * In all Path Management messages:
383 * - TID: is not used and shall be set to 0.
384 * - Flow Label is not used and shall be set to 0
385 * In signalling messages:
386 * - number: this field is not yet used in signalling messages.
387 * It shall be set to 255 by the sender and shall be ignored
388 * by the receiver
389 * Returns true if the echo req was correct, false otherwise.
390 */
d33bd757 391static bool gtp0_validate_echo_hdr(struct gtp0_header *gtp0)
9af41cc3
WD		 392{
393 return !(gtp0->tid || (gtp0->flags ^ 0x1e) ||
394 gtp0->number != 0xff || gtp0->flow);
395}
396
d33bd757
WD		 397/* msg_type has to be GTP_ECHO_REQ or GTP_ECHO_RSP */
398static void gtp0_build_echo_msg(struct gtp0_header *hdr, __u8 msg_type)
399{
400 int len_pkt, len_hdr;
401
402 hdr->flags = 0x1e; /* v0, GTP-non-prime. */
403 hdr->type = msg_type;
404 /* GSM TS 09.60. 7.3 In all Path Management Flow Label and TID
405 * are not used and shall be set to 0.
406 */
407 hdr->flow = 0;
408 hdr->tid = 0;
409 hdr->number = 0xff;
410 hdr->spare[0] = 0xff;
411 hdr->spare[1] = 0xff;
412 hdr->spare[2] = 0xff;
413
414 len_pkt = sizeof(struct gtp0_packet);
415 len_hdr = sizeof(struct gtp0_header);
416
417 if (msg_type == GTP_ECHO_RSP)
418 hdr->length = htons(len_pkt - len_hdr);
419 else
420 hdr->length = 0;
421}
422
750771d0
PNA		 423static int gtp0_send_echo_resp_ip(struct gtp_dev *gtp, struct sk_buff *skb)
424{
425 struct iphdr *iph = ip_hdr(skb);
426 struct flowi4 fl4;
427 struct rtable *rt;
428
429 /* find route to the sender,
430 * src address becomes dst address and vice versa.
431 */
432 rt = ip4_route_output_gtp(&fl4, gtp->sk0, iph->saddr, iph->daddr);
433 if (IS_ERR(rt)) {
434 netdev_dbg(gtp->dev, "no route for echo response from %pI4\n",
435 &iph->saddr);
436 return -1;
437 }
438
439 udp_tunnel_xmit_skb(rt, gtp->sk0, skb,
440 fl4.saddr, fl4.daddr,
441 iph->tos,
442 ip4_dst_hoplimit(&rt->dst),
443 0,
444 htons(GTP0_PORT), htons(GTP0_PORT),
445 !net_eq(sock_net(gtp->sk1u),
446 dev_net(gtp->dev)),
447 false);
448
449 return 0;
450}
451
9af41cc3
WD		 452static int gtp0_send_echo_resp(struct gtp_dev *gtp, struct sk_buff *skb)
453{
454 struct gtp0_packet *gtp_pkt;
455 struct gtp0_header *gtp0;
9af41cc3
WD		 456 __be16 seq;
457
458 gtp0 = (struct gtp0_header *)(skb->data + sizeof(struct udphdr));
459
d33bd757 460 if (!gtp0_validate_echo_hdr(gtp0))
9af41cc3
WD		 461 return -1;
462
463 seq = gtp0->seq;
464
465 /* pull GTP and UDP headers */
466 skb_pull_data(skb, sizeof(struct gtp0_header) + sizeof(struct udphdr));
467
468 gtp_pkt = skb_push(skb, sizeof(struct gtp0_packet));
469 memset(gtp_pkt, 0, sizeof(struct gtp0_packet));
470
d33bd757 471 gtp0_build_echo_msg(&gtp_pkt->gtp0_h, GTP_ECHO_RSP);
9af41cc3
WD		 472
473 /* GSM TS 09.60. 7.3 The Sequence Number in a signalling response
474 * message shall be copied from the signalling request message
475 * that the GSN is replying to.
476 */
477 gtp_pkt->gtp0_h.seq = seq;
478
9af41cc3
WD		 479 gtp_pkt->ie.tag = GTPIE_RECOVERY;
480 gtp_pkt->ie.val = gtp->restart_count;
481
750771d0
PNA		 482 switch (gtp->sk0->sk_family) {
483 case AF_INET:
484 if (gtp0_send_echo_resp_ip(gtp, skb) < 0)
485 return -1;
486 break;
487 case AF_INET6:
9af41cc3
WD		 488 return -1;
489 }
490
9af41cc3
WD		 491 return 0;
492}
493
d33bd757
WD		 494static int gtp_genl_fill_echo(struct sk_buff *skb, u32 snd_portid, u32 snd_seq,
495 int flags, u32 type, struct echo_info echo)
496{
497 void *genlh;
498
499 genlh = genlmsg_put(skb, snd_portid, snd_seq, &gtp_genl_family, flags,
500 type);
501 if (!genlh)
502 goto failure;
503
504 if (nla_put_u32(skb, GTPA_VERSION, echo.gtp_version) ||
750771d0
PNA		 505 nla_put_be32(skb, GTPA_PEER_ADDRESS, echo.peer.addr.s_addr) ||
506 nla_put_be32(skb, GTPA_MS_ADDRESS, echo.ms.addr.s_addr))
d33bd757
WD		 507 goto failure;
508
509 genlmsg_end(skb, genlh);
510 return 0;
511
512failure:
513 genlmsg_cancel(skb, genlh);
514 return -EMSGSIZE;
515}
516
750771d0
PNA		 517static void gtp0_handle_echo_resp_ip(struct sk_buff *skb, struct echo_info *echo)
518{
519 struct iphdr *iph = ip_hdr(skb);
520
521 echo->ms.addr.s_addr = iph->daddr;
522 echo->peer.addr.s_addr = iph->saddr;
523 echo->gtp_version = GTP_V0;
524}
525
d33bd757
WD		 526static int gtp0_handle_echo_resp(struct gtp_dev *gtp, struct sk_buff *skb)
527{
528 struct gtp0_header *gtp0;
529 struct echo_info echo;
530 struct sk_buff *msg;
d33bd757
WD		 531 int ret;
532
533 gtp0 = (struct gtp0_header *)(skb->data + sizeof(struct udphdr));
534
535 if (!gtp0_validate_echo_hdr(gtp0))
536 return -1;
537
750771d0
PNA		 538 switch (gtp->sk0->sk_family) {
539 case AF_INET:
540 gtp0_handle_echo_resp_ip(skb, &echo);
541 break;
542 case AF_INET6:
543 return -1;
544 }
d33bd757
WD		 545
546 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
547 if (!msg)
548 return -ENOMEM;
549
550 ret = gtp_genl_fill_echo(msg, 0, 0, 0, GTP_CMD_ECHOREQ, echo);
551 if (ret < 0) {
552 nlmsg_free(msg);
553 return ret;
554 }
555
556 return genlmsg_multicast_netns(&gtp_genl_family, dev_net(gtp->dev),
557 msg, 0, GTP_GENL_MCGRP, GFP_ATOMIC);
558}
559
c75fc0b9
PNA		 560static int gtp_proto_to_family(__u16 proto)
561{
562 switch (proto) {
563 case ETH_P_IP:
564 return AF_INET;
565 case ETH_P_IPV6:
566 return AF_INET6;
567 default:
568 WARN_ON_ONCE(1);
569 break;
570 }
571
572 return AF_UNSPEC;
573}
574
459aa660 575/* 1 means pass up to the stack, -1 means drop and 0 means decapsulated. */
101cfbc1 576static int gtp0_udp_encap_recv(struct gtp_dev *gtp, struct sk_buff *skb)
459aa660
PN		 577{
578 unsigned int hdrlen = sizeof(struct udphdr) +
579 sizeof(struct gtp0_header);
580 struct gtp0_header *gtp0;
49ecc587 581 struct pdp_ctx *pctx;
c75fc0b9 582 __u16 inner_proto;
459aa660
PN		 583
584 if (!pskb_may_pull(skb, hdrlen))
585 return -1;
586
587 gtp0 = (struct gtp0_header *)(skb->data + sizeof(struct udphdr));
588
589 if ((gtp0->flags >> 5) != GTP_V0)
590 return 1;
591
9af41cc3
WD		 592 /* If the sockets were created in kernel, it means that
593 * there is no daemon running in userspace which would
594 * handle echo request.
595 */
596 if (gtp0->type == GTP_ECHO_REQ && gtp->sk_created)
597 return gtp0_send_echo_resp(gtp, skb);
598
d33bd757
WD		 599 if (gtp0->type == GTP_ECHO_RSP && gtp->sk_created)
600 return gtp0_handle_echo_resp(gtp, skb);
601
49ecc587
JB		 602 if (gtp0->type != GTP_TPDU)
603 return 1;
604
c75fc0b9
PNA		 605 if (gtp_inner_proto(skb, hdrlen, &inner_proto) < 0) {
606 netdev_dbg(gtp->dev, "GTP packet does not encapsulate an IP packet\n");
607 return -1;
608 }
609
610 pctx = gtp0_pdp_find(gtp, be64_to_cpu(gtp0->tid),
611 gtp_proto_to_family(inner_proto));
49ecc587
JB		 612 if (!pctx) {
613 netdev_dbg(gtp->dev, "No PDP ctx to decap skb=%p\n", skb);
614 return 1;
615 }
616
c75fc0b9 617 return gtp_rx(pctx, skb, hdrlen, gtp->role, inner_proto);
459aa660
PN		 618}
619
d33bd757
WD		 620/* msg_type has to be GTP_ECHO_REQ or GTP_ECHO_RSP */
621static void gtp1u_build_echo_msg(struct gtp1_header_long *hdr, __u8 msg_type)
622{
623 int len_pkt, len_hdr;
624
625 /* S flag must be set to 1 */
626 hdr->flags = 0x32; /* v1, GTP-non-prime. */
627 hdr->type = msg_type;
628 /* 3GPP TS 29.281 5.1 - TEID has to be set to 0 */
629 hdr->tid = 0;
630
631 /* seq, npdu and next should be counted to the length of the GTP packet
632 * that's why szie of gtp1_header should be subtracted,
633 * not size of gtp1_header_long.
634 */
635
636 len_hdr = sizeof(struct gtp1_header);
637
638 if (msg_type == GTP_ECHO_RSP) {
639 len_pkt = sizeof(struct gtp1u_packet);
640 hdr->length = htons(len_pkt - len_hdr);
641 } else {
642 /* GTP_ECHO_REQ does not carry GTP Information Element,
643 * the why gtp1_header_long is used here.
644 */
645 len_pkt = sizeof(struct gtp1_header_long);
646 hdr->length = htons(len_pkt - len_hdr);
647 }
648}
649
9af41cc3
WD		 650static int gtp1u_send_echo_resp(struct gtp_dev *gtp, struct sk_buff *skb)
651{
652 struct gtp1_header_long *gtp1u;
653 struct gtp1u_packet *gtp_pkt;
654 struct rtable *rt;
655 struct flowi4 fl4;
656 struct iphdr *iph;
657
658 gtp1u = (struct gtp1_header_long *)(skb->data + sizeof(struct udphdr));
659
660 /* 3GPP TS 29.281 5.1 - For the Echo Request, Echo Response,
661 * Error Indication and Supported Extension Headers Notification
662 * messages, the S flag shall be set to 1 and TEID shall be set to 0.
663 */
664 if (!(gtp1u->flags & GTP1_F_SEQ) || gtp1u->tid)
665 return -1;
666
667 /* pull GTP and UDP headers */
668 skb_pull_data(skb,
669 sizeof(struct gtp1_header_long) + sizeof(struct udphdr));
670
671 gtp_pkt = skb_push(skb, sizeof(struct gtp1u_packet));
672 memset(gtp_pkt, 0, sizeof(struct gtp1u_packet));
673
d33bd757 674 gtp1u_build_echo_msg(&gtp_pkt->gtp1u_h, GTP_ECHO_RSP);
9af41cc3
WD		 675
676 /* 3GPP TS 29.281 7.7.2 - The Restart Counter value in the
677 * Recovery information element shall not be used, i.e. it shall
678 * be set to zero by the sender and shall be ignored by the receiver.
679 * The Recovery information element is mandatory due to backwards
680 * compatibility reasons.
681 */
682 gtp_pkt->ie.tag = GTPIE_RECOVERY;
683 gtp_pkt->ie.val = 0;
684
685 iph = ip_hdr(skb);
686
687 /* find route to the sender,
688 * src address becomes dst address and vice versa.
689 */
690 rt = ip4_route_output_gtp(&fl4, gtp->sk1u, iph->saddr, iph->daddr);
691 if (IS_ERR(rt)) {
692 netdev_dbg(gtp->dev, "no route for echo response from %pI4\n",
693 &iph->saddr);
694 return -1;
695 }
696
697 udp_tunnel_xmit_skb(rt, gtp->sk1u, skb,
698 fl4.saddr, fl4.daddr,
699 iph->tos,
700 ip4_dst_hoplimit(&rt->dst),
701 0,
702 htons(GTP1U_PORT), htons(GTP1U_PORT),
703 !net_eq(sock_net(gtp->sk1u),
704 dev_net(gtp->dev)),
705 false);
706 return 0;
707}
708
d33bd757
WD		 709static int gtp1u_handle_echo_resp(struct gtp_dev *gtp, struct sk_buff *skb)
710{
711 struct gtp1_header_long *gtp1u;
712 struct echo_info echo;
713 struct sk_buff *msg;
714 struct iphdr *iph;
715 int ret;
716
717 gtp1u = (struct gtp1_header_long *)(skb->data + sizeof(struct udphdr));
718
719 /* 3GPP TS 29.281 5.1 - For the Echo Request, Echo Response,
720 * Error Indication and Supported Extension Headers Notification
721 * messages, the S flag shall be set to 1 and TEID shall be set to 0.
722 */
723 if (!(gtp1u->flags & GTP1_F_SEQ) || gtp1u->tid)
724 return -1;
725
726 iph = ip_hdr(skb);
750771d0
PNA		 727 echo.ms.addr.s_addr = iph->daddr;
728 echo.peer.addr.s_addr = iph->saddr;
d33bd757
WD		 729 echo.gtp_version = GTP_V1;
730
731 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
732 if (!msg)
733 return -ENOMEM;
734
735 ret = gtp_genl_fill_echo(msg, 0, 0, 0, GTP_CMD_ECHOREQ, echo);
736 if (ret < 0) {
737 nlmsg_free(msg);
738 return ret;
739 }
740
741 return genlmsg_multicast_netns(&gtp_genl_family, dev_net(gtp->dev),
742 msg, 0, GTP_GENL_MCGRP, GFP_ATOMIC);
743}
744
b6fc0956
PNA		 745static int gtp_parse_exthdrs(struct sk_buff *skb, unsigned int *hdrlen)
746{
747 struct gtp_ext_hdr *gtp_exthdr, _gtp_exthdr;
748 unsigned int offset = *hdrlen;
749 __u8 *next_type, _next_type;
750
751 /* From 29.060: "The Extension Header Length field specifies the length
752 * of the particular Extension header in 4 octets units."
753 *
754 * This length field includes length field size itself (1 byte),
755 * payload (variable length) and next type (1 byte). The extension
756 * header is aligned to to 4 bytes.
757 */
758
759 do {
760 gtp_exthdr = skb_header_pointer(skb, offset, sizeof(*gtp_exthdr),
761 &_gtp_exthdr);
762 if (!gtp_exthdr || !gtp_exthdr->len)
763 return -1;
764
765 offset += gtp_exthdr->len * 4;
766
767 /* From 29.060: "If no such Header follows, then the value of
768 * the Next Extension Header Type shall be 0."
769 */
770 next_type = skb_header_pointer(skb, offset - 1,
771 sizeof(_next_type), &_next_type);
772 if (!next_type)
773 return -1;
774
775 } while (*next_type != 0);
776
777 *hdrlen = offset;
778
779 return 0;
780}
781
101cfbc1 782static int gtp1u_udp_encap_recv(struct gtp_dev *gtp, struct sk_buff *skb)
459aa660
PN		 783{
784 unsigned int hdrlen = sizeof(struct udphdr) +
785 sizeof(struct gtp1_header);
786 struct gtp1_header *gtp1;
49ecc587 787 struct pdp_ctx *pctx;
c75fc0b9 788 __u16 inner_proto;
459aa660
PN		 789
790 if (!pskb_may_pull(skb, hdrlen))
791 return -1;
792
793 gtp1 = (struct gtp1_header *)(skb->data + sizeof(struct udphdr));
794
795 if ((gtp1->flags >> 5) != GTP_V1)
796 return 1;
797
9af41cc3
WD		 798 /* If the sockets were created in kernel, it means that
799 * there is no daemon running in userspace which would
800 * handle echo request.
801 */
802 if (gtp1->type == GTP_ECHO_REQ && gtp->sk_created)
803 return gtp1u_send_echo_resp(gtp, skb);
804
d33bd757
WD		 805 if (gtp1->type == GTP_ECHO_RSP && gtp->sk_created)
806 return gtp1u_handle_echo_resp(gtp, skb);
807
49ecc587
JB		 808 if (gtp1->type != GTP_TPDU)
809 return 1;
810
459aa660
PN		 811 /* From 29.060: "This field shall be present if and only if any one or
812 * more of the S, PN and E flags are set.".
813 *
814 * If any of the bit is set, then the remaining ones also have to be
815 * set.
816 */
49ecc587
JB		 817 if (gtp1->flags & GTP1_F_MASK)
818 hdrlen += 4;
819
459aa660
PN		 820 /* Make sure the header is larger enough, including extensions. */
821 if (!pskb_may_pull(skb, hdrlen))
822 return -1;
823
c75fc0b9
PNA		 824 if (gtp_inner_proto(skb, hdrlen, &inner_proto) < 0) {
825 netdev_dbg(gtp->dev, "GTP packet does not encapsulate an IP packet\n");
826 return -1;
827 }
828
93edb8c7
PN		 829 gtp1 = (struct gtp1_header *)(skb->data + sizeof(struct udphdr));
830
c75fc0b9
PNA		 831 pctx = gtp1_pdp_find(gtp, ntohl(gtp1->tid),
832 gtp_proto_to_family(inner_proto));
49ecc587
JB		 833 if (!pctx) {
834 netdev_dbg(gtp->dev, "No PDP ctx to decap skb=%p\n", skb);
835 return 1;
836 }
837
b6fc0956
PNA		 838 if (gtp1->flags & GTP1_F_EXTHDR &&
839 gtp_parse_exthdrs(skb, &hdrlen) < 0)
840 return -1;
841
c75fc0b9 842 return gtp_rx(pctx, skb, hdrlen, gtp->role, inner_proto);
459aa660
PN		 843}
844
1788b856 845static void __gtp_encap_destroy(struct sock *sk)
459aa660 846{
1e3a3abd 847 struct gtp_dev *gtp;
459aa660 848
e198987e
TY		 849 lock_sock(sk);
850 gtp = sk->sk_user_data;
1e3a3abd 851 if (gtp) {
1788b856
TY		 852 if (gtp->sk0 == sk)
853 gtp->sk0 = NULL;
854 else
855 gtp->sk1u = NULL;
70a36f57 856 WRITE_ONCE(udp_sk(sk)->encap_type, 0);
1e3a3abd 857 rcu_assign_sk_user_data(sk, NULL);
ce3aee71 858 release_sock(sk);
1e3a3abd 859 sock_put(sk);
ce3aee71 860 return;
1e3a3abd 861 }
e198987e 862 release_sock(sk);
459aa660
PN		 863}
864
1788b856
TY		 865static void gtp_encap_destroy(struct sock *sk)
866{
867 rtnl_lock();
868 __gtp_encap_destroy(sk);
869 rtnl_unlock();
870}
871
1e3a3abd 872static void gtp_encap_disable_sock(struct sock *sk)
459aa660 873{
1e3a3abd
AS		 874 if (!sk)
875 return;
459aa660 876
1788b856 877 __gtp_encap_destroy(sk);
1e3a3abd
AS		 878}
879
880static void gtp_encap_disable(struct gtp_dev *gtp)
881{
b20dc3c6
WD		 882 if (gtp->sk_created) {
883 udp_tunnel_sock_release(gtp->sk0->sk_socket);
884 udp_tunnel_sock_release(gtp->sk1u->sk_socket);
885 gtp->sk_created = false;
886 gtp->sk0 = NULL;
887 gtp->sk1u = NULL;
888 } else {
889 gtp_encap_disable_sock(gtp->sk0);
890 gtp_encap_disable_sock(gtp->sk1u);
891 }
459aa660
PN		 892}
893
894/* UDP encapsulation receive handler. See net/ipv4/udp.c.
895 * Return codes: 0: success, <0: error, >0: pass up to userspace UDP socket.
896 */
897static int gtp_encap_recv(struct sock *sk, struct sk_buff *skb)
898{
459aa660 899 struct gtp_dev *gtp;
5b171f9c 900 int ret = 0;
459aa660
PN		 901
902 gtp = rcu_dereference_sk_user_data(sk);
903 if (!gtp)
904 return 1;
905
49ecc587 906 netdev_dbg(gtp->dev, "encap_recv sk=%p\n", sk);
459aa660 907
70a36f57 908 switch (READ_ONCE(udp_sk(sk)->encap_type)) {
459aa660
PN		 909 case UDP_ENCAP_GTP0:
910 netdev_dbg(gtp->dev, "received GTP0 packet\n");
101cfbc1 911 ret = gtp0_udp_encap_recv(gtp, skb);
459aa660
PN		 912 break;
913 case UDP_ENCAP_GTP1U:
914 netdev_dbg(gtp->dev, "received GTP1U packet\n");
101cfbc1 915 ret = gtp1u_udp_encap_recv(gtp, skb);
459aa660
PN		 916 break;
917 default:
918 ret = -1; /* Shouldn't happen. */
919 }
920
921 switch (ret) {
922 case 1:
923 netdev_dbg(gtp->dev, "pass up to the process\n");
5b171f9c 924 break;
459aa660 925 case 0:
459aa660
PN		 926 break;
927 case -1:
928 netdev_dbg(gtp->dev, "GTP packet has been dropped\n");
929 kfree_skb(skb);
5b171f9c
AS		 930 ret = 0;
931 break;
459aa660
PN		 932 }
933
5b171f9c 934 return ret;
459aa660
PN		 935}
936
459aa660
PN		 937static void gtp_dev_uninit(struct net_device *dev)
938{
939 struct gtp_dev *gtp = netdev_priv(dev);
940
941 gtp_encap_disable(gtp);
459aa660
PN		 942}
943
459aa660
PN		 944static inline void gtp0_push_header(struct sk_buff *skb, struct pdp_ctx *pctx)
945{
946 int payload_len = skb->len;
947 struct gtp0_header *gtp0;
948
d58ff351 949 gtp0 = skb_push(skb, sizeof(*gtp0));
459aa660
PN		 950
951 gtp0->flags = 0x1e; /* v0, GTP-non-prime. */
952 gtp0->type = GTP_TPDU;
953 gtp0->length = htons(payload_len);
954 gtp0->seq = htons((atomic_inc_return(&pctx->tx_seq) - 1) % 0xffff);
955 gtp0->flow = htons(pctx->u.v0.flow);
956 gtp0->number = 0xff;
957 gtp0->spare[0] = gtp0->spare[1] = gtp0->spare[2] = 0xff;
958 gtp0->tid = cpu_to_be64(pctx->u.v0.tid);
959}
960
49ecc587 961static inline void gtp1_push_header(struct sk_buff *skb, struct pdp_ctx *pctx)
459aa660
PN		 962{
963 int payload_len = skb->len;
964 struct gtp1_header *gtp1;
965
d58ff351 966 gtp1 = skb_push(skb, sizeof(*gtp1));
459aa660
PN		 967
968 /* Bits 8 7 6 5 4 3 2 1
969 * +--+--+--+--+--+--+--+--+
d928be81 970 * |version |PT| 0| E| S|PN|
459aa660
PN		 971 * +--+--+--+--+--+--+--+--+
972 * 0 0 1 1 1 0 0 0
973 */
d928be81 974 gtp1->flags = 0x30; /* v1, GTP-non-prime. */
459aa660
PN		 975 gtp1->type = GTP_TPDU;
976 gtp1->length = htons(payload_len);
49ecc587 977 gtp1->tid = htonl(pctx->u.v1.o_tei);
459aa660 978
ec674565 979 /* TODO: Support for extension header, sequence number and N-PDU.
459aa660
PN		 980 * Update the length field if any of them is available.
981 */
982}
983
49ecc587
JB		 984struct gtp_pktinfo {
985 struct sock *sk;
750771d0
PNA		 986 union {
987 struct flowi4 fl4;
999cb275 988 struct flowi6 fl6;
750771d0
PNA		 989 };
990 union {
991 struct rtable *rt;
999cb275 992 struct rt6_info *rt6;
750771d0 993 };
49ecc587
JB		 994 struct pdp_ctx *pctx;
995 struct net_device *dev;
559101a7 996 __u8 tos;
49ecc587
JB		 997 __be16 gtph_port;
998};
9ab7e76a 999
49ecc587
JB		 1000static void gtp_push_header(struct sk_buff *skb, struct gtp_pktinfo *pktinfo)
1001{
1002 switch (pktinfo->pctx->gtp_version) {
1003 case GTP_V0:
1004 pktinfo->gtph_port = htons(GTP0_PORT);
1005 gtp0_push_header(skb, pktinfo->pctx);
1006 break;
1007 case GTP_V1:
1008 pktinfo->gtph_port = htons(GTP1U_PORT);
1009 gtp1_push_header(skb, pktinfo->pctx);
1010 break;
459aa660
PN		 1011 }
1012}
1013
1014static inline void gtp_set_pktinfo_ipv4(struct gtp_pktinfo *pktinfo,
559101a7 1015 struct sock *sk, __u8 tos,
49ecc587 1016 struct pdp_ctx *pctx, struct rtable *rt,
459aa660
PN		 1017 struct flowi4 *fl4,
1018 struct net_device *dev)
1019{
1020 pktinfo->sk = sk;
559101a7 1021 pktinfo->tos = tos;
49ecc587 1022 pktinfo->pctx = pctx;
459aa660
PN		 1023 pktinfo->rt = rt;
1024 pktinfo->fl4 = *fl4;
1025 pktinfo->dev = dev;
1026}
1027
999cb275 1028static void gtp_set_pktinfo_ipv6(struct gtp_pktinfo *pktinfo,
559101a7 1029 struct sock *sk, __u8 tos,
999cb275
PNA		 1030 struct pdp_ctx *pctx, struct rt6_info *rt6,
1031 struct flowi6 *fl6,
1032 struct net_device *dev)
1033{
1034 pktinfo->sk = sk;
559101a7 1035 pktinfo->tos = tos;
999cb275
PNA		 1036 pktinfo->pctx = pctx;
1037 pktinfo->rt6 = rt6;
1038 pktinfo->fl6 = *fl6;
1039 pktinfo->dev = dev;
1040}
1041
b77732f0
PNA		 1042static int gtp_build_skb_outer_ip4(struct sk_buff *skb, struct net_device *dev,
1043 struct gtp_pktinfo *pktinfo,
1044 struct pdp_ctx *pctx, __u8 tos,
1045 __be16 frag_off)
459aa660 1046{
459aa660
PN		 1047 struct rtable *rt;
1048 struct flowi4 fl4;
49ecc587 1049 __be16 df;
459aa660
PN		 1050 int mtu;
1051
750771d0 1052 rt = ip4_route_output_gtp(&fl4, pctx->sk, pctx->peer.addr.s_addr,
9af41cc3 1053 inet_sk(pctx->sk)->inet_saddr);
459aa660 1054 if (IS_ERR(rt)) {
49ecc587 1055 netdev_dbg(dev, "no route to SSGN %pI4\n",
750771d0 1056 &pctx->peer.addr.s_addr);
459aa660
PN		 1057 dev->stats.tx_carrier_errors++;
1058 goto err;
1059 }
1060
1061 if (rt->dst.dev == dev) {
49ecc587 1062 netdev_dbg(dev, "circular route to SSGN %pI4\n",
750771d0 1063 &pctx->peer.addr.s_addr);
459aa660
PN		 1064 dev->stats.collisions++;
1065 goto err_rt;
1066 }
1067
459aa660 1068 /* This is similar to tnl_update_pmtu(). */
b77732f0 1069 df = frag_off;
459aa660
PN		 1070 if (df) {
1071 mtu = dst_mtu(&rt->dst) - dev->hard_header_len -
1072 sizeof(struct iphdr) - sizeof(struct udphdr);
49ecc587 1073 switch (pctx->gtp_version) {
459aa660
PN		 1074 case GTP_V0:
1075 mtu -= sizeof(struct gtp0_header);
1076 break;
1077 case GTP_V1:
1078 mtu -= sizeof(struct gtp1_header);
1079 break;
1080 }
1081 } else {
1082 mtu = dst_mtu(&rt->dst);
1083 }
1084
5b71131b 1085 skb_dst_update_pmtu_no_confirm(skb, mtu);
459aa660 1086
b77732f0 1087 if (frag_off & htons(IP_DF) &&
4530e5b8
PNA		 1088 ((!skb_is_gso(skb) && skb->len > mtu) ||
1089 (skb_is_gso(skb) && !skb_gso_validate_network_len(skb, mtu)))) {
49ecc587 1090 netdev_dbg(dev, "packet too big, fragmentation needed\n");
e0fce6f9
JD		 1091 icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
1092 htonl(mtu));
459aa660
PN		 1093 goto err_rt;
1094 }
1095
b77732f0 1096 gtp_set_pktinfo_ipv4(pktinfo, pctx->sk, tos, pctx, rt, &fl4, dev);
49ecc587 1097 gtp_push_header(skb, pktinfo);
459aa660
PN		 1098
1099 return 0;
1100err_rt:
1101 ip_rt_put(rt);
1102err:
1103 return -EBADMSG;
1104}
1105
045a7c15
PNA		 1106static int gtp_build_skb_outer_ip6(struct net *net, struct sk_buff *skb,
1107 struct net_device *dev,
1108 struct gtp_pktinfo *pktinfo,
1109 struct pdp_ctx *pctx, __u8 tos)
1110{
1111 struct dst_entry *dst;
1112 struct rt6_info *rt;
1113 struct flowi6 fl6;
1114 int mtu;
1115
1116 rt = ip6_route_output_gtp(net, &fl6, pctx->sk, &pctx->peer.addr6,
1117 &inet6_sk(pctx->sk)->saddr);
1118 if (IS_ERR(rt)) {
1119 netdev_dbg(dev, "no route to SSGN %pI6\n",
1120 &pctx->peer.addr6);
1121 dev->stats.tx_carrier_errors++;
1122 goto err;
1123 }
1124 dst = &rt->dst;
1125
1126 if (rt->dst.dev == dev) {
1127 netdev_dbg(dev, "circular route to SSGN %pI6\n",
1128 &pctx->peer.addr6);
1129 dev->stats.collisions++;
1130 goto err_rt;
1131 }
1132
1133 mtu = dst_mtu(&rt->dst) - dev->hard_header_len -
1134 sizeof(struct ipv6hdr) - sizeof(struct udphdr);
1135 switch (pctx->gtp_version) {
1136 case GTP_V0:
1137 mtu -= sizeof(struct gtp0_header);
1138 break;
1139 case GTP_V1:
1140 mtu -= sizeof(struct gtp1_header);
1141 break;
1142 }
1143
1144 skb_dst_update_pmtu_no_confirm(skb, mtu);
1145
1146 if ((!skb_is_gso(skb) && skb->len > mtu) ||
1147 (skb_is_gso(skb) && !skb_gso_validate_network_len(skb, mtu))) {
1148 netdev_dbg(dev, "packet too big, fragmentation needed\n");
1149 icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
1150 goto err_rt;
1151 }
1152
1153 gtp_set_pktinfo_ipv6(pktinfo, pctx->sk, tos, pctx, rt, &fl6, dev);
1154 gtp_push_header(skb, pktinfo);
1155
1156 return 0;
1157err_rt:
1158 dst_release(dst);
1159err:
1160 return -EBADMSG;
1161}
1162
b77732f0
PNA		 1163static int gtp_build_skb_ip4(struct sk_buff *skb, struct net_device *dev,
1164 struct gtp_pktinfo *pktinfo)
1165{
1166 struct gtp_dev *gtp = netdev_priv(dev);
e30ea48b 1167 struct net *net = gtp->net;
b77732f0
PNA		 1168 struct pdp_ctx *pctx;
1169 struct iphdr *iph;
1170 int ret;
1171
1172 /* Read the IP destination address and resolve the PDP context.
1173 * Prepend PDP header with TEI/TID from PDP ctx.
1174 */
1175 iph = ip_hdr(skb);
1176 if (gtp->role == GTP_ROLE_SGSN)
1177 pctx = ipv4_pdp_find(gtp, iph->saddr);
1178 else
1179 pctx = ipv4_pdp_find(gtp, iph->daddr);
1180
1181 if (!pctx) {
1182 netdev_dbg(dev, "no PDP ctx found for %pI4, skip\n",
1183 &iph->daddr);
1184 return -ENOENT;
1185 }
1186 netdev_dbg(dev, "found PDP context %p\n", pctx);
1187
e30ea48b
PNA		 1188 switch (pctx->sk->sk_family) {
1189 case AF_INET:
1190 ret = gtp_build_skb_outer_ip4(skb, dev, pktinfo, pctx,
1191 iph->tos, iph->frag_off);
1192 break;
1193 case AF_INET6:
1194 ret = gtp_build_skb_outer_ip6(net, skb, dev, pktinfo, pctx,
1195 iph->tos);
1196 break;
1197 default:
1198 ret = -1;
1199 WARN_ON_ONCE(1);
1200 break;
1201 }
1202
b77732f0
PNA		 1203 if (ret < 0)
1204 return ret;
1205
1206 netdev_dbg(dev, "gtp -> IP src: %pI4 dst: %pI4\n",
1207 &iph->saddr, &iph->daddr);
1208
1209 return 0;
1210}
1211
999cb275
PNA		 1212static int gtp_build_skb_ip6(struct sk_buff *skb, struct net_device *dev,
1213 struct gtp_pktinfo *pktinfo)
1214{
1215 struct gtp_dev *gtp = netdev_priv(dev);
1216 struct net *net = gtp->net;
999cb275
PNA		 1217 struct pdp_ctx *pctx;
1218 struct ipv6hdr *ip6h;
559101a7 1219 __u8 tos;
045a7c15 1220 int ret;
999cb275
PNA		 1221
1222 /* Read the IP destination address and resolve the PDP context.
1223 * Prepend PDP header with TEI/TID from PDP ctx.
1224 */
1225 ip6h = ipv6_hdr(skb);
1226 if (gtp->role == GTP_ROLE_SGSN)
1227 pctx = ipv6_pdp_find(gtp, &ip6h->saddr);
1228 else
1229 pctx = ipv6_pdp_find(gtp, &ip6h->daddr);
1230
1231 if (!pctx) {
1232 netdev_dbg(dev, "no PDP ctx found for %pI6, skip\n",
1233 &ip6h->daddr);
1234 return -ENOENT;
1235 }
1236 netdev_dbg(dev, "found PDP context %p\n", pctx);
1237
559101a7 1238 tos = ipv6_get_dsfield(ip6h);
045a7c15 1239
e30ea48b
PNA		 1240 switch (pctx->sk->sk_family) {
1241 case AF_INET:
1242 ret = gtp_build_skb_outer_ip4(skb, dev, pktinfo, pctx, tos, 0);
1243 break;
1244 case AF_INET6:
1245 ret = gtp_build_skb_outer_ip6(net, skb, dev, pktinfo, pctx, tos);
1246 break;
1247 default:
1248 ret = -1;
1249 WARN_ON_ONCE(1);
1250 break;
1251 }
1252
045a7c15
PNA		 1253 if (ret < 0)
1254 return ret;
999cb275 1255
e0758804
PNA		 1256 netdev_dbg(dev, "gtp -> IP src: %pI6 dst: %pI6\n",
1257 &ip6h->saddr, &ip6h->daddr);
1258
999cb275 1259 return 0;
999cb275
PNA		 1260}
1261
459aa660
PN		 1262static netdev_tx_t gtp_dev_xmit(struct sk_buff *skb, struct net_device *dev)
1263{
49ecc587 1264 unsigned int proto = ntohs(skb->protocol);
459aa660
PN		 1265 struct gtp_pktinfo pktinfo;
1266 int err;
1267
1268 /* Ensure there is sufficient headroom. */
1269 if (skb_cow_head(skb, dev->needed_headroom))
1270 goto tx_err;
1271
1272 skb_reset_inner_headers(skb);
1273
1274 /* PDP context lookups in gtp_build_skb_*() need rcu read-side lock. */
1275 rcu_read_lock();
49ecc587
JB		 1276 switch (proto) {
1277 case ETH_P_IP:
1278 err = gtp_build_skb_ip4(skb, dev, &pktinfo);
1279 break;
999cb275
PNA		 1280 case ETH_P_IPV6:
1281 err = gtp_build_skb_ip6(skb, dev, &pktinfo);
1282 break;
49ecc587
JB		 1283 default:
1284 err = -EOPNOTSUPP;
1285 break;
1286 }
459aa660
PN		 1287 rcu_read_unlock();
1288
1289 if (err < 0)
1290 goto tx_err;
1291
e30ea48b
PNA		 1292 switch (pktinfo.pctx->sk->sk_family) {
1293 case AF_INET:
49ecc587
JB		 1294 udp_tunnel_xmit_skb(pktinfo.rt, pktinfo.sk, skb,
1295 pktinfo.fl4.saddr, pktinfo.fl4.daddr,
559101a7 1296 pktinfo.tos,
49ecc587
JB		 1297 ip4_dst_hoplimit(&pktinfo.rt->dst),
1298 0,
1299 pktinfo.gtph_port, pktinfo.gtph_port,
a9c0df76
JB		 1300 !net_eq(sock_net(pktinfo.pctx->sk),
1301 dev_net(dev)),
1302 false);
49ecc587 1303 break;
e30ea48b 1304 case AF_INET6:
999cb275 1305#if IS_ENABLED(CONFIG_IPV6)
999cb275
PNA		 1306 udp_tunnel6_xmit_skb(&pktinfo.rt6->dst, pktinfo.sk, skb, dev,
1307 &pktinfo.fl6.saddr, &pktinfo.fl6.daddr,
559101a7 1308 pktinfo.tos,
999cb275
PNA		 1309 ip6_dst_hoplimit(&pktinfo.rt->dst),
1310 0,
1311 pktinfo.gtph_port, pktinfo.gtph_port,
1312 false);
1313#else
1314 goto tx_err;
1315#endif
1316 break;
49ecc587 1317 }
459aa660
PN		 1318
1319 return NETDEV_TX_OK;
1320tx_err:
1321 dev->stats.tx_errors++;
1322 dev_kfree_skb(skb);
1323 return NETDEV_TX_OK;
1324}
1325
1326static const struct net_device_ops gtp_netdev_ops = {
459aa660
PN		 1327 .ndo_uninit = gtp_dev_uninit,
1328 .ndo_start_xmit = gtp_dev_xmit,
459aa660
PN		 1329};
1330
29f53b5c
JB		 1331static const struct device_type gtp_type = {
1332 .name = "gtp",
1333};
1334
750771d0
PNA		 1335#define GTP_TH_MAXLEN (sizeof(struct udphdr) + sizeof(struct gtp0_header))
1336#define GTP_IPV4_MAXLEN (sizeof(struct iphdr) + GTP_TH_MAXLEN)
1337
459aa660
PN		 1338static void gtp_link_setup(struct net_device *dev)
1339{
81154bb8 1340 struct gtp_dev *gtp = netdev_priv(dev);
e21eb3a0 1341
459aa660 1342 dev->netdev_ops = &gtp_netdev_ops;
cf124db5 1343 dev->needs_free_netdev = true;
29f53b5c 1344 SET_NETDEV_DEVTYPE(dev, &gtp_type);
459aa660
PN		 1345
1346 dev->hard_header_len = 0;
1347 dev->addr_len = 0;
750771d0 1348 dev->mtu = ETH_DATA_LEN - GTP_IPV4_MAXLEN;
459aa660
PN		 1349
1350 /* Zero header length. */
1351 dev->type = ARPHRD_NONE;
1352 dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
1353
660e5aae 1354 dev->pcpu_stat_type = NETDEV_PCPU_STAT_TSTATS;
459aa660
PN		 1355 dev->priv_flags |= IFF_NO_QUEUE;
1356 dev->features |= NETIF_F_LLTX;
1357 netif_keep_dst(dev);
1358
750771d0 1359 dev->needed_headroom = LL_MAX_HEADER + GTP_IPV4_MAXLEN;
81154bb8 1360 gtp->dev = dev;
459aa660
PN		 1361}
1362
1363static int gtp_hashtable_new(struct gtp_dev *gtp, int hsize);
49ecc587 1364static int gtp_encap_enable(struct gtp_dev *gtp, struct nlattr *data[]);
459aa660 1365
94dc550a
TY		 1366static void gtp_destructor(struct net_device *dev)
1367{
1368 struct gtp_dev *gtp = netdev_priv(dev);
1369
1370 kfree(gtp->addr_hash);
1371 kfree(gtp->tid_hash);
1372}
1373
999cb275
PNA		 1374static int gtp_sock_udp_config(struct udp_port_cfg *udp_conf,
1375 const struct nlattr *nla, int family)
1376{
1377 udp_conf->family = family;
1378
1379 switch (udp_conf->family) {
1380 case AF_INET:
1381 udp_conf->local_ip.s_addr = nla_get_be32(nla);
1382 break;
1383#if IS_ENABLED(CONFIG_IPV6)
1384 case AF_INET6:
1385 udp_conf->local_ip6 = nla_get_in6_addr(nla);
1386 break;
1387#endif
1388 default:
1389 return -EOPNOTSUPP;
1390 }
1391
1392 return 0;
1393}
1394
1395static struct sock *gtp_create_sock(int type, struct gtp_dev *gtp,
1396 const struct nlattr *nla, int family)
b20dc3c6
WD		 1397{
1398 struct udp_tunnel_sock_cfg tuncfg = {};
999cb275 1399 struct udp_port_cfg udp_conf = {};
b20dc3c6
WD		 1400 struct net *net = gtp->net;
1401 struct socket *sock;
1402 int err;
1403
999cb275
PNA		 1404 if (nla) {
1405 err = gtp_sock_udp_config(&udp_conf, nla, family);
1406 if (err < 0)
1407 return ERR_PTR(err);
1408 } else {
1409 udp_conf.local_ip.s_addr = htonl(INADDR_ANY);
1410 udp_conf.family = AF_INET;
1411 }
1412
b20dc3c6
WD		 1413 if (type == UDP_ENCAP_GTP0)
1414 udp_conf.local_udp_port = htons(GTP0_PORT);
1415 else if (type == UDP_ENCAP_GTP1U)
1416 udp_conf.local_udp_port = htons(GTP1U_PORT);
1417 else
1418 return ERR_PTR(-EINVAL);
1419
1420 err = udp_sock_create(net, &udp_conf, &sock);
1421 if (err)
1422 return ERR_PTR(err);
1423
1424 tuncfg.sk_user_data = gtp;
1425 tuncfg.encap_type = type;
1426 tuncfg.encap_rcv = gtp_encap_recv;
1427 tuncfg.encap_destroy = NULL;
1428
1429 setup_udp_tunnel_sock(net, sock, &tuncfg);
1430
1431 return sock->sk;
1432}
1433
999cb275
PNA		 1434static int gtp_create_sockets(struct gtp_dev *gtp, const struct nlattr *nla,
1435 int family)
b20dc3c6 1436{
353f5ffb
PNA		 1437 struct sock *sk1u;
1438 struct sock *sk0;
b20dc3c6 1439
999cb275 1440 sk0 = gtp_create_sock(UDP_ENCAP_GTP0, gtp, nla, family);
b20dc3c6
WD		 1441 if (IS_ERR(sk0))
1442 return PTR_ERR(sk0);
1443
999cb275 1444 sk1u = gtp_create_sock(UDP_ENCAP_GTP1U, gtp, nla, family);
b20dc3c6
WD		 1445 if (IS_ERR(sk1u)) {
1446 udp_tunnel_sock_release(sk0->sk_socket);
1447 return PTR_ERR(sk1u);
1448 }
1449
1450 gtp->sk_created = true;
1451 gtp->sk0 = sk0;
1452 gtp->sk1u = sk1u;
1453
1454 return 0;
1455}
1456
999cb275
PNA		 1457#define GTP_TH_MAXLEN (sizeof(struct udphdr) + sizeof(struct gtp0_header))
1458#define GTP_IPV6_MAXLEN (sizeof(struct ipv6hdr) + GTP_TH_MAXLEN)
1459
459aa660 1460static int gtp_newlink(struct net *src_net, struct net_device *dev,
7a3f4a18
MS		 1461 struct nlattr *tb[], struct nlattr *data[],
1462 struct netlink_ext_ack *extack)
459aa660 1463{
b20dc3c6 1464 unsigned int role = GTP_ROLE_GGSN;
459aa660
PN		 1465 struct gtp_dev *gtp;
1466 struct gtp_net *gn;
1e3a3abd 1467 int hashsize, err;
459aa660 1468
999cb275
PNA		 1469#if !IS_ENABLED(CONFIG_IPV6)
1470 if (data[IFLA_GTP_LOCAL6])
1471 return -EAFNOSUPPORT;
1472#endif
1473
459aa660
PN		 1474 gtp = netdev_priv(dev);
1475
6a902c0f 1476 if (!data[IFLA_GTP_PDP_HASHSIZE]) {
459aa660 1477 hashsize = 1024;
6a902c0f 1478 } else {
459aa660 1479 hashsize = nla_get_u32(data[IFLA_GTP_PDP_HASHSIZE]);
6a902c0f
TY		 1480 if (!hashsize)
1481 hashsize = 1024;
1482 }
459aa660 1483
b20dc3c6
WD		 1484 if (data[IFLA_GTP_ROLE]) {
1485 role = nla_get_u32(data[IFLA_GTP_ROLE]);
1486 if (role > GTP_ROLE_SGSN)
1487 return -EINVAL;
1488 }
1489 gtp->role = role;
1490
9af41cc3
WD		 1491 if (!data[IFLA_GTP_RESTART_COUNT])
1492 gtp->restart_count = 0;
1493 else
1494 gtp->restart_count = nla_get_u8(data[IFLA_GTP_RESTART_COUNT]);
1495
b20dc3c6
WD		 1496 gtp->net = src_net;
1497
459aa660
PN		 1498 err = gtp_hashtable_new(gtp, hashsize);
1499 if (err < 0)
51467431
MF		 1500 return err;
1501
999cb275
PNA		 1502 if (data[IFLA_GTP_CREATE_SOCKETS]) {
1503 if (data[IFLA_GTP_LOCAL6])
1504 err = gtp_create_sockets(gtp, data[IFLA_GTP_LOCAL6], AF_INET6);
1505 else
1506 err = gtp_create_sockets(gtp, data[IFLA_GTP_LOCAL], AF_INET);
1507 } else {
b20dc3c6 1508 err = gtp_encap_enable(gtp, data);
999cb275
PNA		 1509 }
1510
51467431
MF		 1511 if (err < 0)
1512 goto out_hashtable;
459aa660 1513
999cb275
PNA		 1514 if ((gtp->sk0 && gtp->sk0->sk_family == AF_INET6) ||
1515 (gtp->sk1u && gtp->sk1u->sk_family == AF_INET6)) {
1516 dev->mtu = ETH_DATA_LEN - GTP_IPV6_MAXLEN;
1517 dev->needed_headroom = LL_MAX_HEADER + GTP_IPV6_MAXLEN;
1518 }
1519
459aa660
PN		 1520 err = register_netdevice(dev);
1521 if (err < 0) {
1522 netdev_dbg(dev, "failed to register new netdev %d\n", err);
51467431 1523 goto out_encap;
459aa660
PN		 1524 }
1525
1526 gn = net_generic(dev_net(dev), gtp_net_id);
1527 list_add_rcu(&gtp->list, &gn->gtp_dev_list);
94dc550a 1528 dev->priv_destructor = gtp_destructor;
459aa660 1529
49ecc587 1530 netdev_dbg(dev, "registered new GTP interface\n");
459aa660
PN		 1531
1532 return 0;
1533
51467431
MF		 1534out_encap:
1535 gtp_encap_disable(gtp);
459aa660 1536out_hashtable:
94dc550a
TY		 1537 kfree(gtp->addr_hash);
1538 kfree(gtp->tid_hash);
459aa660
PN		 1539 return err;
1540}
1541
1542static void gtp_dellink(struct net_device *dev, struct list_head *head)
1543{
1544 struct gtp_dev *gtp = netdev_priv(dev);
f2a90410 1545 struct hlist_node *next;
94dc550a
TY		 1546 struct pdp_ctx *pctx;
1547 int i;
1548
1549 for (i = 0; i < gtp->hash_size; i++)
f2a90410 1550 hlist_for_each_entry_safe(pctx, next, &gtp->tid_hash[i], hlist_tid)
94dc550a 1551 pdp_context_delete(pctx);
459aa660 1552
459aa660
PN		 1553 list_del_rcu(&gtp->list);
1554 unregister_netdevice_queue(dev, head);
1555}
1556
1557static const struct nla_policy gtp_policy[IFLA_GTP_MAX + 1] = {
1558 [IFLA_GTP_FD0] = { .type = NLA_U32 },
1559 [IFLA_GTP_FD1] = { .type = NLA_U32 },
1560 [IFLA_GTP_PDP_HASHSIZE] = { .type = NLA_U32 },
91ed81f9 1561 [IFLA_GTP_ROLE] = { .type = NLA_U32 },
b20dc3c6 1562 [IFLA_GTP_CREATE_SOCKETS] = { .type = NLA_U8 },
9af41cc3 1563 [IFLA_GTP_RESTART_COUNT] = { .type = NLA_U8 },
999cb275
PNA		 1564 [IFLA_GTP_LOCAL] = { .type = NLA_U32 },
1565 [IFLA_GTP_LOCAL6] = { .len = sizeof(struct in6_addr) },
459aa660
PN		 1566};
1567
a8b8a889
MS		 1568static int gtp_validate(struct nlattr *tb[], struct nlattr *data[],
1569 struct netlink_ext_ack *extack)
459aa660
PN		 1570{
1571 if (!data)
1572 return -EINVAL;
1573
1574 return 0;
1575}
1576
1577static size_t gtp_get_size(const struct net_device *dev)
1578{
e1b2914e 1579 return nla_total_size(sizeof(__u32)) + /* IFLA_GTP_PDP_HASHSIZE */
9af41cc3
WD		 1580 nla_total_size(sizeof(__u32)) + /* IFLA_GTP_ROLE */
1581 nla_total_size(sizeof(__u8)); /* IFLA_GTP_RESTART_COUNT */
459aa660
PN		 1582}
1583
1584static int gtp_fill_info(struct sk_buff *skb, const struct net_device *dev)
1585{
1586 struct gtp_dev *gtp = netdev_priv(dev);
1587
1588 if (nla_put_u32(skb, IFLA_GTP_PDP_HASHSIZE, gtp->hash_size))
1589 goto nla_put_failure;
e1b2914e
JB		 1590 if (nla_put_u32(skb, IFLA_GTP_ROLE, gtp->role))
1591 goto nla_put_failure;
9af41cc3
WD		 1592 if (nla_put_u8(skb, IFLA_GTP_RESTART_COUNT, gtp->restart_count))
1593 goto nla_put_failure;
459aa660
PN		 1594
1595 return 0;
1596
1597nla_put_failure:
1598 return -EMSGSIZE;
1599}
1600
1601static struct rtnl_link_ops gtp_link_ops __read_mostly = {
1602 .kind = "gtp",
1603 .maxtype = IFLA_GTP_MAX,
1604 .policy = gtp_policy,
1605 .priv_size = sizeof(struct gtp_dev),
1606 .setup = gtp_link_setup,
1607 .validate = gtp_validate,
1608 .newlink = gtp_newlink,
1609 .dellink = gtp_dellink,
1610 .get_size = gtp_get_size,
1611 .fill_info = gtp_fill_info,
1612};
1613
459aa660
PN		 1614static int gtp_hashtable_new(struct gtp_dev *gtp, int hsize)
1615{
1616 int i;
1617
6da2ec56 1618 gtp->addr_hash = kmalloc_array(hsize, sizeof(struct hlist_head),
bd5cd35b 1619 GFP_KERNEL | __GFP_NOWARN);
459aa660
PN		 1620 if (gtp->addr_hash == NULL)
1621 return -ENOMEM;
1622
6da2ec56 1623 gtp->tid_hash = kmalloc_array(hsize, sizeof(struct hlist_head),
bd5cd35b 1624 GFP_KERNEL | __GFP_NOWARN);
459aa660
PN		 1625 if (gtp->tid_hash == NULL)
1626 goto err1;
1627
1628 gtp->hash_size = hsize;
1629
1630 for (i = 0; i < hsize; i++) {
1631 INIT_HLIST_HEAD(&gtp->addr_hash[i]);
1632 INIT_HLIST_HEAD(&gtp->tid_hash[i]);
1633 }
1634 return 0;
1635err1:
1636 kfree(gtp->addr_hash);
1637 return -ENOMEM;
1638}
1639
49ecc587
JB		 1640static struct sock *gtp_encap_enable_socket(int fd, int type,
1641 struct gtp_dev *gtp)
459aa660
PN		 1642{
1643 struct udp_tunnel_sock_cfg tuncfg = {NULL};
49ecc587 1644 struct socket *sock;
1e3a3abd 1645 struct sock *sk;
49ecc587
JB		 1646 int err;
1647
1648 pr_debug("enable gtp on %d, %d\n", fd, type);
1649
1650 sock = sockfd_lookup(fd, &err);
1651 if (!sock) {
1652 pr_debug("gtp socket fd=%d not found\n", fd);
1653 return NULL;
1654 }
459aa660 1655
940ba149
ED		 1656 sk = sock->sk;
1657 if (sk->sk_protocol != IPPROTO_UDP ||
1658 sk->sk_type != SOCK_DGRAM ||
1659 (sk->sk_family != AF_INET && sk->sk_family != AF_INET6)) {
49ecc587
JB		 1660 pr_debug("socket fd=%d not UDP\n", fd);
1661 sk = ERR_PTR(-EINVAL);
1662 goto out_sock;
459aa660
PN		 1663 }
1664
999cb275
PNA		 1665 if (sk->sk_family == AF_INET6 &&
1666 !sk->sk_ipv6only) {
1667 sk = ERR_PTR(-EADDRNOTAVAIL);
1668 goto out_sock;
1669 }
1670
940ba149
ED		 1671 lock_sock(sk);
1672 if (sk->sk_user_data) {
49ecc587
JB		 1673 sk = ERR_PTR(-EBUSY);
1674 goto out_rel_sock;
459aa660
PN		 1675 }
1676
1e3a3abd 1677 sock_hold(sk);
459aa660
PN		 1678
1679 tuncfg.sk_user_data = gtp;
1e3a3abd 1680 tuncfg.encap_type = type;
459aa660
PN		 1681 tuncfg.encap_rcv = gtp_encap_recv;
1682 tuncfg.encap_destroy = gtp_encap_destroy;
1683
1e3a3abd 1684 setup_udp_tunnel_sock(sock_net(sock->sk), sock, &tuncfg);
9ab7e76a 1685
49ecc587
JB		 1686out_rel_sock:
1687 release_sock(sock->sk);
1688out_sock:
1e3a3abd 1689 sockfd_put(sock);
49ecc587 1690 return sk;
1e3a3abd 1691}
459aa660 1692
49ecc587 1693static int gtp_encap_enable(struct gtp_dev *gtp, struct nlattr *data[])
1e3a3abd
AS		 1694{
1695 struct sock *sk1u = NULL;
1696 struct sock *sk0 = NULL;
b20dc3c6
WD		 1697
1698 if (!data[IFLA_GTP_FD0] && !data[IFLA_GTP_FD1])
1699 return -EINVAL;
1e3a3abd
AS		 1700
1701 if (data[IFLA_GTP_FD0]) {
1702 u32 fd0 = nla_get_u32(data[IFLA_GTP_FD0]);
1703
1704 sk0 = gtp_encap_enable_socket(fd0, UDP_ENCAP_GTP0, gtp);
1705 if (IS_ERR(sk0))
1706 return PTR_ERR(sk0);
1707 }
1708
1709 if (data[IFLA_GTP_FD1]) {
1710 u32 fd1 = nla_get_u32(data[IFLA_GTP_FD1]);
1711
1712 sk1u = gtp_encap_enable_socket(fd1, UDP_ENCAP_GTP1U, gtp);
1713 if (IS_ERR(sk1u)) {
b289ba5e 1714 gtp_encap_disable_sock(sk0);
1e3a3abd
AS		 1715 return PTR_ERR(sk1u);
1716 }
1717 }
1718
1719 gtp->sk0 = sk0;
1720 gtp->sk1u = sk1u;
1721
999cb275
PNA		 1722 if (sk0 && sk1u &&
1723 sk0->sk_family != sk1u->sk_family) {
1724 gtp_encap_disable_sock(sk0);
1725 gtp_encap_disable_sock(sk1u);
1726 return -EINVAL;
1727 }
1728
1e3a3abd 1729 return 0;
459aa660
PN		 1730}
1731
3fb94617 1732static struct gtp_dev *gtp_find_dev(struct net *src_net, struct nlattr *nla[])
459aa660 1733{
3fb94617
AS		 1734 struct gtp_dev *gtp = NULL;
1735 struct net_device *dev;
1736 struct net *net;
459aa660 1737
3fb94617
AS		 1738 /* Examine the link attributes and figure out which network namespace
1739 * we are talking about.
1740 */
1741 if (nla[GTPA_NET_NS_FD])
1742 net = get_net_ns_by_fd(nla_get_u32(nla[GTPA_NET_NS_FD]));
1743 else
1744 net = get_net(src_net);
1745
1746 if (IS_ERR(net))
1747 return NULL;
1748
1749 /* Check if there's an existing gtpX device to configure */
1750 dev = dev_get_by_index_rcu(net, nla_get_u32(nla[GTPA_LINK]));
65d786c2 1751 if (dev && dev->netdev_ops == &gtp_netdev_ops)
3fb94617
AS		 1752 gtp = netdev_priv(dev);
1753
1754 put_net(net);
1755 return gtp;
459aa660
PN		 1756}
1757
999cb275 1758static void gtp_pdp_fill(struct pdp_ctx *pctx, struct genl_info *info)
459aa660
PN		 1759{
1760 pctx->gtp_version = nla_get_u32(info->attrs[GTPA_VERSION]);
459aa660
PN		 1761
1762 switch (pctx->gtp_version) {
1763 case GTP_V0:
1764 /* According to TS 09.60, sections 7.5.1 and 7.5.2, the flow
1765 * label needs to be the same for uplink and downlink packets,
1766 * so let's annotate this.
1767 */
1768 pctx->u.v0.tid = nla_get_u64(info->attrs[GTPA_TID]);
1769 pctx->u.v0.flow = nla_get_u16(info->attrs[GTPA_FLOW]);
1770 break;
1771 case GTP_V1:
1772 pctx->u.v1.i_tei = nla_get_u32(info->attrs[GTPA_I_TEI]);
1773 pctx->u.v1.o_tei = nla_get_u32(info->attrs[GTPA_O_TEI]);
1774 break;
1775 default:
1776 break;
1777 }
1778}
1779
e30ea48b
PNA		 1780static void ip_pdp_peer_fill(struct pdp_ctx *pctx, struct genl_info *info)
1781{
1782 if (info->attrs[GTPA_PEER_ADDRESS]) {
1783 pctx->peer.addr.s_addr =
1784 nla_get_be32(info->attrs[GTPA_PEER_ADDRESS]);
1785 } else if (info->attrs[GTPA_PEER_ADDR6]) {
1786 pctx->peer.addr6 = nla_get_in6_addr(info->attrs[GTPA_PEER_ADDR6]);
1787 }
1788}
1789
999cb275
PNA		 1790static void ipv4_pdp_fill(struct pdp_ctx *pctx, struct genl_info *info)
1791{
e30ea48b 1792 ip_pdp_peer_fill(pctx, info);
999cb275
PNA		 1793 pctx->ms.addr.s_addr =
1794 nla_get_be32(info->attrs[GTPA_MS_ADDRESS]);
1795 gtp_pdp_fill(pctx, info);
1796}
1797
c6461ec9 1798static bool ipv6_pdp_fill(struct pdp_ctx *pctx, struct genl_info *info)
999cb275 1799{
e30ea48b 1800 ip_pdp_peer_fill(pctx, info);
999cb275 1801 pctx->ms.addr6 = nla_get_in6_addr(info->attrs[GTPA_MS_ADDR6]);
c6461ec9
PNA		 1802 if (pctx->ms.addr6.s6_addr32[2] ||
1803 pctx->ms.addr6.s6_addr32[3])
1804 return false;
1805
999cb275 1806 gtp_pdp_fill(pctx, info);
c6461ec9
PNA		 1807
1808 return true;
999cb275
PNA		 1809}
1810
50aba46c
ND		 1811static struct pdp_ctx *gtp_pdp_add(struct gtp_dev *gtp, struct sock *sk,
1812 struct genl_info *info)
459aa660 1813{
6b01b1d9 1814 struct pdp_ctx *pctx, *pctx_tid = NULL;
3fb94617 1815 struct net_device *dev = gtp->dev;
459aa660 1816 u32 hash_ms, hash_tid = 0;
999cb275 1817 struct in6_addr ms_addr6;
6b01b1d9 1818 unsigned int version;
459aa660
PN		 1819 bool found = false;
1820 __be32 ms_addr;
999cb275 1821 int family;
459aa660 1822
6b01b1d9 1823 version = nla_get_u32(info->attrs[GTPA_VERSION]);
459aa660 1824
999cb275
PNA		 1825 if (info->attrs[GTPA_FAMILY])
1826 family = nla_get_u8(info->attrs[GTPA_FAMILY]);
1827 else
1828 family = AF_INET;
1829
1830#if !IS_ENABLED(CONFIG_IPV6)
1831 if (family == AF_INET6)
1832 return ERR_PTR(-EAFNOSUPPORT);
1833#endif
e30ea48b
PNA		 1834 if (!info->attrs[GTPA_PEER_ADDRESS] &&
1835 !info->attrs[GTPA_PEER_ADDR6])
1836 return ERR_PTR(-EINVAL);
999cb275
PNA		 1837
1838 if ((info->attrs[GTPA_PEER_ADDRESS] &&
1839 sk->sk_family == AF_INET6) ||
1840 (info->attrs[GTPA_PEER_ADDR6] &&
1841 sk->sk_family == AF_INET))
1842 return ERR_PTR(-EAFNOSUPPORT);
1843
1844 switch (family) {
1845 case AF_INET:
1846 if (!info->attrs[GTPA_MS_ADDRESS] ||
e30ea48b 1847 info->attrs[GTPA_MS_ADDR6])
999cb275
PNA		 1848 return ERR_PTR(-EINVAL);
1849
1850 ms_addr = nla_get_be32(info->attrs[GTPA_MS_ADDRESS]);
1851 hash_ms = ipv4_hashfn(ms_addr) % gtp->hash_size;
1852 pctx = ipv4_pdp_find(gtp, ms_addr);
1853 break;
1854 case AF_INET6:
1855 if (!info->attrs[GTPA_MS_ADDR6] ||
e30ea48b 1856 info->attrs[GTPA_MS_ADDRESS])
999cb275
PNA		 1857 return ERR_PTR(-EINVAL);
1858
1859 ms_addr6 = nla_get_in6_addr(info->attrs[GTPA_MS_ADDR6]);
1860 hash_ms = ipv6_hashfn(&ms_addr6) % gtp->hash_size;
1861 pctx = ipv6_pdp_find(gtp, &ms_addr6);
1862 break;
1863 default:
1864 return ERR_PTR(-EAFNOSUPPORT);
1865 }
6b01b1d9
TY		 1866 if (pctx)
1867 found = true;
1868 if (version == GTP_V0)
1869 pctx_tid = gtp0_pdp_find(gtp,
c75fc0b9
PNA		 1870 nla_get_u64(info->attrs[GTPA_TID]),
1871 family);
6b01b1d9
TY		 1872 else if (version == GTP_V1)
1873 pctx_tid = gtp1_pdp_find(gtp,
c75fc0b9
PNA		 1874 nla_get_u32(info->attrs[GTPA_I_TEI]),
1875 family);
6b01b1d9
TY		 1876 if (pctx_tid)
1877 found = true;
459aa660
PN		 1878
1879 if (found) {
1880 if (info->nlhdr->nlmsg_flags & NLM_F_EXCL)
50aba46c 1881 return ERR_PTR(-EEXIST);
459aa660 1882 if (info->nlhdr->nlmsg_flags & NLM_F_REPLACE)
50aba46c 1883 return ERR_PTR(-EOPNOTSUPP);
459aa660 1884
6b01b1d9 1885 if (pctx && pctx_tid)
50aba46c 1886 return ERR_PTR(-EEXIST);
6b01b1d9
TY		 1887 if (!pctx)
1888 pctx = pctx_tid;
1889
999cb275
PNA		 1890 switch (pctx->af) {
1891 case AF_INET:
1892 ipv4_pdp_fill(pctx, info);
1893 break;
1894 case AF_INET6:
c6461ec9
PNA		 1895 if (!ipv6_pdp_fill(pctx, info))
1896 return ERR_PTR(-EADDRNOTAVAIL);
999cb275
PNA		 1897 break;
1898 }
459aa660
PN		 1899
1900 if (pctx->gtp_version == GTP_V0)
1901 netdev_dbg(dev, "GTPv0-U: update tunnel id = %llx (pdp %p)\n",
1902 pctx->u.v0.tid, pctx);
1903 else if (pctx->gtp_version == GTP_V1)
1904 netdev_dbg(dev, "GTPv1-U: update tunnel id = %x/%x (pdp %p)\n",
1905 pctx->u.v1.i_tei, pctx->u.v1.o_tei, pctx);
1906
50aba46c 1907 return pctx;
459aa660
PN		 1908
1909 }
1910
3f167e19 1911 pctx = kmalloc(sizeof(*pctx), GFP_ATOMIC);
459aa660 1912 if (pctx == NULL)
50aba46c 1913 return ERR_PTR(-ENOMEM);
459aa660 1914
101cfbc1
AS		 1915 sock_hold(sk);
1916 pctx->sk = sk;
5b171f9c 1917 pctx->dev = gtp->dev;
999cb275
PNA		 1918 pctx->af = family;
1919
1920 switch (pctx->af) {
1921 case AF_INET:
e30ea48b 1922 if (!info->attrs[GTPA_MS_ADDRESS]) {
999cb275
PNA		 1923 sock_put(sk);
1924 kfree(pctx);
1925 return ERR_PTR(-EINVAL);
1926 }
1927
1928 ipv4_pdp_fill(pctx, info);
1929 break;
1930 case AF_INET6:
e30ea48b 1931 if (!info->attrs[GTPA_MS_ADDR6]) {
999cb275
PNA		 1932 sock_put(sk);
1933 kfree(pctx);
1934 return ERR_PTR(-EINVAL);
1935 }
1936
c6461ec9
PNA		 1937 if (!ipv6_pdp_fill(pctx, info)) {
1938 sock_put(sk);
1939 kfree(pctx);
1940 return ERR_PTR(-EADDRNOTAVAIL);
1941 }
999cb275
PNA		 1942 break;
1943 }
459aa660
PN		 1944 atomic_set(&pctx->tx_seq, 0);
1945
1946 switch (pctx->gtp_version) {
1947 case GTP_V0:
1948 /* TS 09.60: "The flow label identifies unambiguously a GTP
1949 * flow.". We use the tid for this instead, I cannot find a
1950 * situation in which this doesn't unambiguosly identify the
1951 * PDP context.
1952 */
1953 hash_tid = gtp0_hashfn(pctx->u.v0.tid) % gtp->hash_size;
1954 break;
1955 case GTP_V1:
1956 hash_tid = gtp1u_hashfn(pctx->u.v1.i_tei) % gtp->hash_size;
1957 break;
1958 }
1959
1960 hlist_add_head_rcu(&pctx->hlist_addr, &gtp->addr_hash[hash_ms]);
1961 hlist_add_head_rcu(&pctx->hlist_tid, &gtp->tid_hash[hash_tid]);
1962
1963 switch (pctx->gtp_version) {
1964 case GTP_V0:
1965 netdev_dbg(dev, "GTPv0-U: new PDP ctx id=%llx ssgn=%pI4 ms=%pI4 (pdp=%p)\n",
750771d0
PNA		 1966 pctx->u.v0.tid, &pctx->peer.addr,
1967 &pctx->ms.addr, pctx);
459aa660
PN		 1968 break;
1969 case GTP_V1:
1970 netdev_dbg(dev, "GTPv1-U: new PDP ctx id=%x/%x ssgn=%pI4 ms=%pI4 (pdp=%p)\n",
1971 pctx->u.v1.i_tei, pctx->u.v1.o_tei,
750771d0 1972 &pctx->peer.addr, &pctx->ms.addr, pctx);
459aa660
PN		 1973 break;
1974 }
1975
50aba46c 1976 return pctx;
459aa660
PN		 1977}
1978
101cfbc1
AS		 1979static void pdp_context_free(struct rcu_head *head)
1980{
1981 struct pdp_ctx *pctx = container_of(head, struct pdp_ctx, rcu_head);
1982
1983 sock_put(pctx->sk);
1984 kfree(pctx);
1985}
1986
6b5e2e74
AS		 1987static void pdp_context_delete(struct pdp_ctx *pctx)
1988{
1989 hlist_del_rcu(&pctx->hlist_tid);
1990 hlist_del_rcu(&pctx->hlist_addr);
101cfbc1 1991 call_rcu(&pctx->rcu_head, pdp_context_free);
6b5e2e74
AS		 1992}
1993
151ea46f 1994static int gtp_tunnel_notify(struct pdp_ctx *pctx, u8 cmd, gfp_t allocation);
50aba46c 1995
459aa660
PN		 1996static int gtp_genl_new_pdp(struct sk_buff *skb, struct genl_info *info)
1997{
101cfbc1 1998 unsigned int version;
50aba46c 1999 struct pdp_ctx *pctx;
3fb94617 2000 struct gtp_dev *gtp;
101cfbc1 2001 struct sock *sk;
3fb94617 2002 int err;
459aa660
PN		 2003
2004 if (!info->attrs[GTPA_VERSION] ||
999cb275 2005 !info->attrs[GTPA_LINK])
459aa660
PN		 2006 return -EINVAL;
2007
101cfbc1
AS		 2008 version = nla_get_u32(info->attrs[GTPA_VERSION]);
2009
2010 switch (version) {
459aa660
PN		 2011 case GTP_V0:
2012 if (!info->attrs[GTPA_TID] ||
2013 !info->attrs[GTPA_FLOW])
2014 return -EINVAL;
2015 break;
2016 case GTP_V1:
2017 if (!info->attrs[GTPA_I_TEI] ||
2018 !info->attrs[GTPA_O_TEI])
2019 return -EINVAL;
2020 break;
2021
2022 default:
2023 return -EINVAL;
2024 }
2025
1788b856 2026 rtnl_lock();
459aa660 2027
3fb94617
AS		 2028 gtp = gtp_find_dev(sock_net(skb->sk), info->attrs);
2029 if (!gtp) {
2030 err = -ENODEV;
2031 goto out_unlock;
27ee441a 2032 }
459aa660 2033
101cfbc1
AS		 2034 if (version == GTP_V0)
2035 sk = gtp->sk0;
2036 else if (version == GTP_V1)
2037 sk = gtp->sk1u;
2038 else
2039 sk = NULL;
2040
2041 if (!sk) {
2042 err = -ENODEV;
2043 goto out_unlock;
2044 }
2045
50aba46c
ND		 2046 pctx = gtp_pdp_add(gtp, sk, info);
2047 if (IS_ERR(pctx)) {
2048 err = PTR_ERR(pctx);
2049 } else {
151ea46f 2050 gtp_tunnel_notify(pctx, GTP_CMD_NEWPDP, GFP_KERNEL);
50aba46c
ND		 2051 err = 0;
2052 }
3fb94617
AS		 2053
2054out_unlock:
1788b856 2055 rtnl_unlock();
3fb94617 2056 return err;
459aa660
PN		 2057}
2058
d9e2dd12
AS		 2059static struct pdp_ctx *gtp_find_pdp_by_link(struct net *net,
2060 struct nlattr *nla[])
459aa660 2061{
459aa660 2062 struct gtp_dev *gtp;
c75fc0b9
PNA		 2063 int family;
2064
2065 if (nla[GTPA_FAMILY])
2066 family = nla_get_u8(nla[GTPA_FAMILY]);
2067 else
2068 family = AF_INET;
459aa660 2069
d9e2dd12
AS		 2070 gtp = gtp_find_dev(net, nla);
2071 if (!gtp)
2072 return ERR_PTR(-ENODEV);
459aa660 2073
d9e2dd12
AS		 2074 if (nla[GTPA_MS_ADDRESS]) {
2075 __be32 ip = nla_get_be32(nla[GTPA_MS_ADDRESS]);
459aa660 2076
c75fc0b9
PNA		 2077 if (family != AF_INET)
2078 return ERR_PTR(-EINVAL);
2079
d9e2dd12 2080 return ipv4_pdp_find(gtp, ip);
999cb275
PNA		 2081 } else if (nla[GTPA_MS_ADDR6]) {
2082 struct in6_addr addr = nla_get_in6_addr(nla[GTPA_MS_ADDR6]);
2083
c75fc0b9
PNA		 2084 if (family != AF_INET6)
2085 return ERR_PTR(-EINVAL);
2086
c6461ec9
PNA		 2087 if (addr.s6_addr32[2] ||
2088 addr.s6_addr32[3])
2089 return ERR_PTR(-EADDRNOTAVAIL);
2090
999cb275 2091 return ipv6_pdp_find(gtp, &addr);
d9e2dd12
AS		 2092 } else if (nla[GTPA_VERSION]) {
2093 u32 gtp_version = nla_get_u32(nla[GTPA_VERSION]);
2094
c75fc0b9
PNA		 2095 if (gtp_version == GTP_V0 && nla[GTPA_TID]) {
2096 return gtp0_pdp_find(gtp, nla_get_u64(nla[GTPA_TID]),
2097 family);
2098 } else if (gtp_version == GTP_V1 && nla[GTPA_I_TEI]) {
2099 return gtp1_pdp_find(gtp, nla_get_u32(nla[GTPA_I_TEI]),
2100 family);
2101 }
27ee441a 2102 }
459aa660 2103
d9e2dd12
AS		 2104 return ERR_PTR(-EINVAL);
2105}
459aa660 2106
d9e2dd12
AS		 2107static struct pdp_ctx *gtp_find_pdp(struct net *net, struct nlattr *nla[])
2108{
2109 struct pdp_ctx *pctx;
459aa660 2110
d9e2dd12
AS		 2111 if (nla[GTPA_LINK])
2112 pctx = gtp_find_pdp_by_link(net, nla);
2113 else
2114 pctx = ERR_PTR(-EINVAL);
2115
2116 if (!pctx)
2117 pctx = ERR_PTR(-ENOENT);
2118
2119 return pctx;
2120}
2121
2122static int gtp_genl_del_pdp(struct sk_buff *skb, struct genl_info *info)
2123{
2124 struct pdp_ctx *pctx;
2125 int err = 0;
2126
2127 if (!info->attrs[GTPA_VERSION])
2128 return -EINVAL;
2129
2130 rcu_read_lock();
2131
2132 pctx = gtp_find_pdp(sock_net(skb->sk), info->attrs);
2133 if (IS_ERR(pctx)) {
2134 err = PTR_ERR(pctx);
3fb94617
AS		 2135 goto out_unlock;
2136 }
459aa660
PN		 2137
2138 if (pctx->gtp_version == GTP_V0)
d9e2dd12 2139 netdev_dbg(pctx->dev, "GTPv0-U: deleting tunnel id = %llx (pdp %p)\n",
459aa660
PN		 2140 pctx->u.v0.tid, pctx);
2141 else if (pctx->gtp_version == GTP_V1)
d9e2dd12 2142 netdev_dbg(pctx->dev, "GTPv1-U: deleting tunnel id = %x/%x (pdp %p)\n",
459aa660
PN		 2143 pctx->u.v1.i_tei, pctx->u.v1.o_tei, pctx);
2144
151ea46f 2145 gtp_tunnel_notify(pctx, GTP_CMD_DELPDP, GFP_ATOMIC);
6b5e2e74 2146 pdp_context_delete(pctx);
459aa660 2147
3fb94617
AS		 2148out_unlock:
2149 rcu_read_unlock();
2150 return err;
459aa660
PN		 2151}
2152
459aa660 2153static int gtp_genl_fill_info(struct sk_buff *skb, u32 snd_portid, u32 snd_seq,
846c68f7 2154 int flags, u32 type, struct pdp_ctx *pctx)
459aa660
PN		 2155{
2156 void *genlh;
2157
846c68f7 2158 genlh = genlmsg_put(skb, snd_portid, snd_seq, &gtp_genl_family, flags,
459aa660
PN		 2159 type);
2160 if (genlh == NULL)
2161 goto nlmsg_failure;
2162
2163 if (nla_put_u32(skb, GTPA_VERSION, pctx->gtp_version) ||
b274e47d 2164 nla_put_u32(skb, GTPA_LINK, pctx->dev->ifindex) ||
999cb275 2165 nla_put_u8(skb, GTPA_FAMILY, pctx->af))
459aa660
PN		 2166 goto nla_put_failure;
2167
999cb275
PNA		 2168 switch (pctx->af) {
2169 case AF_INET:
e30ea48b
PNA		 2170 if (nla_put_be32(skb, GTPA_MS_ADDRESS, pctx->ms.addr.s_addr))
2171 goto nla_put_failure;
2172 break;
2173 case AF_INET6:
2174 if (nla_put_in6_addr(skb, GTPA_MS_ADDR6, &pctx->ms.addr6))
2175 goto nla_put_failure;
2176 break;
2177 }
2178
2179 switch (pctx->sk->sk_family) {
2180 case AF_INET:
2181 if (nla_put_be32(skb, GTPA_PEER_ADDRESS, pctx->peer.addr.s_addr))
999cb275
PNA		 2182 goto nla_put_failure;
2183 break;
2184 case AF_INET6:
e30ea48b 2185 if (nla_put_in6_addr(skb, GTPA_PEER_ADDR6, &pctx->peer.addr6))
999cb275
PNA		 2186 goto nla_put_failure;
2187 break;
2188 }
2189
459aa660
PN		 2190 switch (pctx->gtp_version) {
2191 case GTP_V0:
2192 if (nla_put_u64_64bit(skb, GTPA_TID, pctx->u.v0.tid, GTPA_PAD) ||
2193 nla_put_u16(skb, GTPA_FLOW, pctx->u.v0.flow))
2194 goto nla_put_failure;
2195 break;
2196 case GTP_V1:
2197 if (nla_put_u32(skb, GTPA_I_TEI, pctx->u.v1.i_tei) ||
2198 nla_put_u32(skb, GTPA_O_TEI, pctx->u.v1.o_tei))
2199 goto nla_put_failure;
2200 break;
2201 }
2202 genlmsg_end(skb, genlh);
2203 return 0;
2204
2205nlmsg_failure:
2206nla_put_failure:
2207 genlmsg_cancel(skb, genlh);
2208 return -EMSGSIZE;
2209}
2210
151ea46f 2211static int gtp_tunnel_notify(struct pdp_ctx *pctx, u8 cmd, gfp_t allocation)
50aba46c
ND		 2212{
2213 struct sk_buff *msg;
2214 int ret;
2215
151ea46f 2216 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, allocation);
50aba46c
ND		 2217 if (!msg)
2218 return -ENOMEM;
2219
2220 ret = gtp_genl_fill_info(msg, 0, 0, 0, cmd, pctx);
2221 if (ret < 0) {
2222 nlmsg_free(msg);
2223 return ret;
2224 }
2225
2226 ret = genlmsg_multicast_netns(&gtp_genl_family, dev_net(pctx->dev), msg,
2227 0, GTP_GENL_MCGRP, GFP_ATOMIC);
2228 return ret;
2229}
2230
459aa660
PN		 2231static int gtp_genl_get_pdp(struct sk_buff *skb, struct genl_info *info)
2232{
2233 struct pdp_ctx *pctx = NULL;
459aa660 2234 struct sk_buff *skb2;
459aa660
PN		 2235 int err;
2236
d9e2dd12 2237 if (!info->attrs[GTPA_VERSION])
459aa660 2238 return -EINVAL;
459aa660 2239
3fb94617 2240 rcu_read_lock();
459aa660 2241
d9e2dd12
AS		 2242 pctx = gtp_find_pdp(sock_net(skb->sk), info->attrs);
2243 if (IS_ERR(pctx)) {
2244 err = PTR_ERR(pctx);
459aa660
PN		 2245 goto err_unlock;
2246 }
2247
2248 skb2 = genlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC);
2249 if (skb2 == NULL) {
2250 err = -ENOMEM;
2251 goto err_unlock;
2252 }
2253
846c68f7
YK		 2254 err = gtp_genl_fill_info(skb2, NETLINK_CB(skb).portid, info->snd_seq,
2255 0, info->nlhdr->nlmsg_type, pctx);
459aa660
PN		 2256 if (err < 0)
2257 goto err_unlock_free;
2258
2259 rcu_read_unlock();
2260 return genlmsg_unicast(genl_info_net(info), skb2, info->snd_portid);
2261
2262err_unlock_free:
2263 kfree_skb(skb2);
2264err_unlock:
2265 rcu_read_unlock();
2266 return err;
2267}
2268
2269static int gtp_genl_dump_pdp(struct sk_buff *skb,
2270 struct netlink_callback *cb)
2271{
2272 struct gtp_dev *last_gtp = (struct gtp_dev *)cb->args[2], *gtp;
94a6d9fb 2273 int i, j, bucket = cb->args[0], skip = cb->args[1];
459aa660 2274 struct net *net = sock_net(skb->sk);
459aa660 2275 struct pdp_ctx *pctx;
94a6d9fb
TY		 2276 struct gtp_net *gn;
2277
2278 gn = net_generic(net, gtp_net_id);
459aa660
PN		 2279
2280 if (cb->args[4])
2281 return 0;
2282
94a6d9fb 2283 rcu_read_lock();
459aa660
PN		 2284 list_for_each_entry_rcu(gtp, &gn->gtp_dev_list, list) {
2285 if (last_gtp && last_gtp != gtp)
2286 continue;
2287 else
2288 last_gtp = NULL;
2289
94a6d9fb
TY		 2290 for (i = bucket; i < gtp->hash_size; i++) {
2291 j = 0;
2292 hlist_for_each_entry_rcu(pctx, &gtp->tid_hash[i],
2293 hlist_tid) {
2294 if (j >= skip &&
2295 gtp_genl_fill_info(skb,
2296 NETLINK_CB(cb->skb).portid,
2297 cb->nlh->nlmsg_seq,
846c68f7 2298 NLM_F_MULTI,
94a6d9fb 2299 cb->nlh->nlmsg_type, pctx)) {
459aa660 2300 cb->args[0] = i;
94a6d9fb 2301 cb->args[1] = j;
459aa660
PN		 2302 cb->args[2] = (unsigned long)gtp;
2303 goto out;
2304 }
94a6d9fb 2305 j++;
459aa660 2306 }
94a6d9fb 2307 skip = 0;
459aa660 2308 }
94a6d9fb 2309 bucket = 0;
459aa660
PN		 2310 }
2311 cb->args[4] = 1;
2312out:
94a6d9fb 2313 rcu_read_unlock();
459aa660
PN		 2314 return skb->len;
2315}
2316
d33bd757
WD		 2317static int gtp_genl_send_echo_req(struct sk_buff *skb, struct genl_info *info)
2318{
2319 struct sk_buff *skb_to_send;
2320 __be32 src_ip, dst_ip;
2321 unsigned int version;
2322 struct gtp_dev *gtp;
2323 struct flowi4 fl4;
2324 struct rtable *rt;
2325 struct sock *sk;
2326 __be16 port;
2327 int len;
2328
2329 if (!info->attrs[GTPA_VERSION] ||
2330 !info->attrs[GTPA_LINK] ||
2331 !info->attrs[GTPA_PEER_ADDRESS] ||
2332 !info->attrs[GTPA_MS_ADDRESS])
2333 return -EINVAL;
2334
2335 version = nla_get_u32(info->attrs[GTPA_VERSION]);
2336 dst_ip = nla_get_be32(info->attrs[GTPA_PEER_ADDRESS]);
2337 src_ip = nla_get_be32(info->attrs[GTPA_MS_ADDRESS]);
2338
2339 gtp = gtp_find_dev(sock_net(skb->sk), info->attrs);
2340 if (!gtp)
2341 return -ENODEV;
2342
2343 if (!gtp->sk_created)
2344 return -EOPNOTSUPP;
2345 if (!(gtp->dev->flags & IFF_UP))
2346 return -ENETDOWN;
2347
2348 if (version == GTP_V0) {
2349 struct gtp0_header *gtp0_h;
2350
2351 len = LL_RESERVED_SPACE(gtp->dev) + sizeof(struct gtp0_header) +
2352 sizeof(struct iphdr) + sizeof(struct udphdr);
2353
2354 skb_to_send = netdev_alloc_skb_ip_align(gtp->dev, len);
2355 if (!skb_to_send)
2356 return -ENOMEM;
2357
2358 sk = gtp->sk0;
2359 port = htons(GTP0_PORT);
2360
2361 gtp0_h = skb_push(skb_to_send, sizeof(struct gtp0_header));
2362 memset(gtp0_h, 0, sizeof(struct gtp0_header));
2363 gtp0_build_echo_msg(gtp0_h, GTP_ECHO_REQ);
2364 } else if (version == GTP_V1) {
2365 struct gtp1_header_long *gtp1u_h;
2366
2367 len = LL_RESERVED_SPACE(gtp->dev) +
2368 sizeof(struct gtp1_header_long) +
2369 sizeof(struct iphdr) + sizeof(struct udphdr);
2370
2371 skb_to_send = netdev_alloc_skb_ip_align(gtp->dev, len);
2372 if (!skb_to_send)
2373 return -ENOMEM;
2374
2375 sk = gtp->sk1u;
2376 port = htons(GTP1U_PORT);
2377
2378 gtp1u_h = skb_push(skb_to_send,
2379 sizeof(struct gtp1_header_long));
2380 memset(gtp1u_h, 0, sizeof(struct gtp1_header_long));
2381 gtp1u_build_echo_msg(gtp1u_h, GTP_ECHO_REQ);
2382 } else {
2383 return -ENODEV;
2384 }
2385
2386 rt = ip4_route_output_gtp(&fl4, sk, dst_ip, src_ip);
2387 if (IS_ERR(rt)) {
2388 netdev_dbg(gtp->dev, "no route for echo request to %pI4\n",
2389 &dst_ip);
02f39338 2390 kfree_skb(skb_to_send);
d33bd757
WD		 2391 return -ENODEV;
2392 }
2393
2394 udp_tunnel_xmit_skb(rt, sk, skb_to_send,
2395 fl4.saddr, fl4.daddr,
2396 fl4.flowi4_tos,
2397 ip4_dst_hoplimit(&rt->dst),
2398 0,
2399 port, port,
2400 !net_eq(sock_net(sk),
2401 dev_net(gtp->dev)),
2402 false);
2403 return 0;
2404}
2405
5761917a 2406static const struct nla_policy gtp_genl_policy[GTPA_MAX + 1] = {
459aa660
PN		 2407 [GTPA_LINK] = { .type = NLA_U32, },
2408 [GTPA_VERSION] = { .type = NLA_U32, },
2409 [GTPA_TID] = { .type = NLA_U64, },
ae6336b5 2410 [GTPA_PEER_ADDRESS] = { .type = NLA_U32, },
459aa660
PN		 2411 [GTPA_MS_ADDRESS] = { .type = NLA_U32, },
2412 [GTPA_FLOW] = { .type = NLA_U16, },
2413 [GTPA_NET_NS_FD] = { .type = NLA_U32, },
2414 [GTPA_I_TEI] = { .type = NLA_U32, },
2415 [GTPA_O_TEI] = { .type = NLA_U32, },
999cb275
PNA		 2416 [GTPA_PEER_ADDR6] = { .len = sizeof(struct in6_addr), },
2417 [GTPA_MS_ADDR6] = { .len = sizeof(struct in6_addr), },
2418 [GTPA_FAMILY] = { .type = NLA_U8, },
459aa660
PN		 2419};
2420
66a9b928 2421static const struct genl_small_ops gtp_genl_ops[] = {
459aa660
PN		 2422 {
2423 .cmd = GTP_CMD_NEWPDP,
ef6243ac 2424 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
459aa660 2425 .doit = gtp_genl_new_pdp,
459aa660
PN		 2426 .flags = GENL_ADMIN_PERM,
2427 },
2428 {
2429 .cmd = GTP_CMD_DELPDP,
ef6243ac 2430 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
459aa660 2431 .doit = gtp_genl_del_pdp,
459aa660
PN		 2432 .flags = GENL_ADMIN_PERM,
2433 },
2434 {
2435 .cmd = GTP_CMD_GETPDP,
ef6243ac 2436 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
459aa660
PN		 2437 .doit = gtp_genl_get_pdp,
2438 .dumpit = gtp_genl_dump_pdp,
459aa660
PN		 2439 .flags = GENL_ADMIN_PERM,
2440 },
d33bd757
WD		 2441 {
2442 .cmd = GTP_CMD_ECHOREQ,
2443 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
2444 .doit = gtp_genl_send_echo_req,
2445 .flags = GENL_ADMIN_PERM,
2446 },
459aa660
PN		 2447};
2448
56989f6d 2449static struct genl_family gtp_genl_family __ro_after_init = {
489111e5
JB		 2450 .name = "gtp",
2451 .version = 0,
2452 .hdrsize = 0,
2453 .maxattr = GTPA_MAX,
3b0f31f2 2454 .policy = gtp_genl_policy,
489111e5
JB		 2455 .netnsok = true,
2456 .module = THIS_MODULE,
66a9b928
JK		 2457 .small_ops = gtp_genl_ops,
2458 .n_small_ops = ARRAY_SIZE(gtp_genl_ops),
9c5d03d3 2459 .resv_start_op = GTP_CMD_ECHOREQ + 1,
50aba46c
ND		 2460 .mcgrps = gtp_genl_mcgrps,
2461 .n_mcgrps = ARRAY_SIZE(gtp_genl_mcgrps),
489111e5
JB		 2462};
2463
459aa660
PN		 2464static int __net_init gtp_net_init(struct net *net)
2465{
2466 struct gtp_net *gn = net_generic(net, gtp_net_id);
2467
2468 INIT_LIST_HEAD(&gn->gtp_dev_list);
2469 return 0;
2470}
2471
6eedda01
ED		 2472static void __net_exit gtp_net_exit_batch_rtnl(struct list_head *net_list,
2473 struct list_head *dev_to_kill)
459aa660 2474{
6eedda01 2475 struct net *net;
459aa660 2476
6eedda01
ED		 2477 list_for_each_entry(net, net_list, exit_list) {
2478 struct gtp_net *gn = net_generic(net, gtp_net_id);
2479 struct gtp_dev *gtp;
459aa660 2480
6eedda01
ED		 2481 list_for_each_entry(gtp, &gn->gtp_dev_list, list)
2482 gtp_dellink(gtp->dev, dev_to_kill);
2483 }
459aa660
PN		 2484}
2485
2486static struct pernet_operations gtp_net_ops = {
2487 .init = gtp_net_init,
6eedda01 2488 .exit_batch_rtnl = gtp_net_exit_batch_rtnl,
459aa660
PN		 2489 .id = &gtp_net_id,
2490 .size = sizeof(struct gtp_net),
2491};
2492
2493static int __init gtp_init(void)
2494{
2495 int err;
2496
2497 get_random_bytes(&gtp_h_initval, sizeof(gtp_h_initval));
2498
616d82c3 2499 err = register_pernet_subsys(&gtp_net_ops);
459aa660
PN		 2500 if (err < 0)
2501 goto error_out;
2502
616d82c3 2503 err = rtnl_link_register(&gtp_link_ops);
459aa660 2504 if (err < 0)
616d82c3 2505 goto unreg_pernet_subsys;
459aa660 2506
136cfaca 2507 err = genl_register_family(&gtp_genl_family);
459aa660 2508 if (err < 0)
616d82c3 2509 goto unreg_rtnl_link;
459aa660 2510
49ecc587 2511 pr_info("GTP module loaded (pdp ctx size %zd bytes)\n",
459aa660
PN		 2512 sizeof(struct pdp_ctx));
2513 return 0;
2514
459aa660
PN		 2515unreg_rtnl_link:
2516 rtnl_link_unregister(&gtp_link_ops);
616d82c3
AO		 2517unreg_pernet_subsys:
2518 unregister_pernet_subsys(&gtp_net_ops);
459aa660
PN		 2519error_out:
2520 pr_err("error loading GTP module loaded\n");
2521 return err;
2522}
2523late_initcall(gtp_init);
2524
2525static void __exit gtp_fini(void)
2526{
459aa660
PN		 2527 genl_unregister_family(&gtp_genl_family);
2528 rtnl_link_unregister(&gtp_link_ops);
a2bed907 2529 unregister_pernet_subsys(&gtp_net_ops);
459aa660
PN		 2530
2531 pr_info("GTP module unloaded\n");
2532}
2533module_exit(gtp_fini);
2534
2535MODULE_LICENSE("GPL");
2536MODULE_AUTHOR("Harald Welte <hwelte@sysmocom.de>");
2537MODULE_DESCRIPTION("Interface driver for GTP encapsulated traffic");
2538MODULE_ALIAS_RTNL_LINK("gtp");
ab729823 2539MODULE_ALIAS_GENL_FAMILY("gtp");
Linux 6.x block layer and io_uring tree(s)