1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* GTP according to GSM TS 09.60 / 3GPP TS 29.060
4 * (C) 2012-2014 by sysmocom - s.f.m.c. GmbH
5 * (C) 2016 by Pablo Neira Ayuso <pablo@netfilter.org>
7 * Author: Harald Welte <hwelte@sysmocom.de>
8 * Pablo Neira Ayuso <pablo@netfilter.org>
9 * Andreas Schultz <aschultz@travelping.com>
12 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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>
24 #include <net/net_namespace.h>
25 #include <net/protocol.h>
28 #include <net/udp_tunnel.h>
31 #include <net/genetlink.h>
32 #include <net/netns/generic.h>
35 /* An active session for the subscriber. */
37 struct hlist_node hlist_tid;
38 struct hlist_node hlist_addr;
53 struct in_addr ms_addr_ip4;
54 struct in_addr peer_addr_ip4;
57 struct net_device *dev;
60 struct rcu_head rcu_head;
63 /* One instance of the GTP device. */
65 struct list_head list;
71 struct net_device *dev;
75 unsigned int hash_size;
76 struct hlist_head *tid_hash;
77 struct hlist_head *addr_hash;
83 struct in_addr ms_addr_ip4;
84 struct in_addr peer_addr_ip4;
88 static unsigned int gtp_net_id __read_mostly;
91 struct list_head gtp_dev_list;
94 static u32 gtp_h_initval;
96 static struct genl_family gtp_genl_family;
98 enum gtp_multicast_groups {
102 static const struct genl_multicast_group gtp_genl_mcgrps[] = {
103 [GTP_GENL_MCGRP] = { .name = GTP_GENL_MCGRP_NAME },
106 static void pdp_context_delete(struct pdp_ctx *pctx);
108 static inline u32 gtp0_hashfn(u64 tid)
110 u32 *tid32 = (u32 *) &tid;
111 return jhash_2words(tid32[0], tid32[1], gtp_h_initval);
114 static inline u32 gtp1u_hashfn(u32 tid)
116 return jhash_1word(tid, gtp_h_initval);
119 static inline u32 ipv4_hashfn(__be32 ip)
121 return jhash_1word((__force u32)ip, gtp_h_initval);
124 /* Resolve a PDP context structure based on the 64bit TID. */
125 static struct pdp_ctx *gtp0_pdp_find(struct gtp_dev *gtp, u64 tid)
127 struct hlist_head *head;
130 head = >p->tid_hash[gtp0_hashfn(tid) % gtp->hash_size];
132 hlist_for_each_entry_rcu(pdp, head, hlist_tid) {
133 if (pdp->gtp_version == GTP_V0 &&
134 pdp->u.v0.tid == tid)
140 /* Resolve a PDP context structure based on the 32bit TEI. */
141 static struct pdp_ctx *gtp1_pdp_find(struct gtp_dev *gtp, u32 tid)
143 struct hlist_head *head;
146 head = >p->tid_hash[gtp1u_hashfn(tid) % gtp->hash_size];
148 hlist_for_each_entry_rcu(pdp, head, hlist_tid) {
149 if (pdp->gtp_version == GTP_V1 &&
150 pdp->u.v1.i_tei == tid)
156 /* Resolve a PDP context based on IPv4 address of MS. */
157 static struct pdp_ctx *ipv4_pdp_find(struct gtp_dev *gtp, __be32 ms_addr)
159 struct hlist_head *head;
162 head = >p->addr_hash[ipv4_hashfn(ms_addr) % gtp->hash_size];
164 hlist_for_each_entry_rcu(pdp, head, hlist_addr) {
165 if (pdp->af == AF_INET &&
166 pdp->ms_addr_ip4.s_addr == ms_addr)
173 static bool gtp_check_ms_ipv4(struct sk_buff *skb, struct pdp_ctx *pctx,
174 unsigned int hdrlen, unsigned int role)
178 if (!pskb_may_pull(skb, hdrlen + sizeof(struct iphdr)))
181 iph = (struct iphdr *)(skb->data + hdrlen);
183 if (role == GTP_ROLE_SGSN)
184 return iph->daddr == pctx->ms_addr_ip4.s_addr;
186 return iph->saddr == pctx->ms_addr_ip4.s_addr;
189 /* Check if the inner IP address in this packet is assigned to any
190 * existing mobile subscriber.
192 static bool gtp_check_ms(struct sk_buff *skb, struct pdp_ctx *pctx,
193 unsigned int hdrlen, unsigned int role)
195 switch (ntohs(skb->protocol)) {
197 return gtp_check_ms_ipv4(skb, pctx, hdrlen, role);
202 static int gtp_rx(struct pdp_ctx *pctx, struct sk_buff *skb,
203 unsigned int hdrlen, unsigned int role)
205 if (!gtp_check_ms(skb, pctx, hdrlen, role)) {
206 netdev_dbg(pctx->dev, "No PDP ctx for this MS\n");
210 /* Get rid of the GTP + UDP headers. */
211 if (iptunnel_pull_header(skb, hdrlen, skb->protocol,
212 !net_eq(sock_net(pctx->sk), dev_net(pctx->dev)))) {
213 pctx->dev->stats.rx_length_errors++;
217 netdev_dbg(pctx->dev, "forwarding packet from GGSN to uplink\n");
219 /* Now that the UDP and the GTP header have been removed, set up the
220 * new network header. This is required by the upper layer to
221 * calculate the transport header.
223 skb_reset_network_header(skb);
224 skb_reset_mac_header(skb);
226 skb->dev = pctx->dev;
228 dev_sw_netstats_rx_add(pctx->dev, skb->len);
234 pctx->dev->stats.rx_dropped++;
238 static struct rtable *ip4_route_output_gtp(struct flowi4 *fl4,
239 const struct sock *sk,
240 __be32 daddr, __be32 saddr)
242 memset(fl4, 0, sizeof(*fl4));
243 fl4->flowi4_oif = sk->sk_bound_dev_if;
246 fl4->flowi4_tos = ip_sock_rt_tos(sk);
247 fl4->flowi4_scope = ip_sock_rt_scope(sk);
248 fl4->flowi4_proto = sk->sk_protocol;
250 return ip_route_output_key(sock_net(sk), fl4);
254 * In all Path Management messages:
255 * - TID: is not used and shall be set to 0.
256 * - Flow Label is not used and shall be set to 0
257 * In signalling messages:
258 * - number: this field is not yet used in signalling messages.
259 * It shall be set to 255 by the sender and shall be ignored
261 * Returns true if the echo req was correct, false otherwise.
263 static bool gtp0_validate_echo_hdr(struct gtp0_header *gtp0)
265 return !(gtp0->tid || (gtp0->flags ^ 0x1e) ||
266 gtp0->number != 0xff || gtp0->flow);
269 /* msg_type has to be GTP_ECHO_REQ or GTP_ECHO_RSP */
270 static void gtp0_build_echo_msg(struct gtp0_header *hdr, __u8 msg_type)
272 int len_pkt, len_hdr;
274 hdr->flags = 0x1e; /* v0, GTP-non-prime. */
275 hdr->type = msg_type;
276 /* GSM TS 09.60. 7.3 In all Path Management Flow Label and TID
277 * are not used and shall be set to 0.
282 hdr->spare[0] = 0xff;
283 hdr->spare[1] = 0xff;
284 hdr->spare[2] = 0xff;
286 len_pkt = sizeof(struct gtp0_packet);
287 len_hdr = sizeof(struct gtp0_header);
289 if (msg_type == GTP_ECHO_RSP)
290 hdr->length = htons(len_pkt - len_hdr);
295 static int gtp0_send_echo_resp(struct gtp_dev *gtp, struct sk_buff *skb)
297 struct gtp0_packet *gtp_pkt;
298 struct gtp0_header *gtp0;
304 gtp0 = (struct gtp0_header *)(skb->data + sizeof(struct udphdr));
306 if (!gtp0_validate_echo_hdr(gtp0))
311 /* pull GTP and UDP headers */
312 skb_pull_data(skb, sizeof(struct gtp0_header) + sizeof(struct udphdr));
314 gtp_pkt = skb_push(skb, sizeof(struct gtp0_packet));
315 memset(gtp_pkt, 0, sizeof(struct gtp0_packet));
317 gtp0_build_echo_msg(>p_pkt->gtp0_h, GTP_ECHO_RSP);
319 /* GSM TS 09.60. 7.3 The Sequence Number in a signalling response
320 * message shall be copied from the signalling request message
321 * that the GSN is replying to.
323 gtp_pkt->gtp0_h.seq = seq;
325 gtp_pkt->ie.tag = GTPIE_RECOVERY;
326 gtp_pkt->ie.val = gtp->restart_count;
330 /* find route to the sender,
331 * src address becomes dst address and vice versa.
333 rt = ip4_route_output_gtp(&fl4, gtp->sk0, iph->saddr, iph->daddr);
335 netdev_dbg(gtp->dev, "no route for echo response from %pI4\n",
340 udp_tunnel_xmit_skb(rt, gtp->sk0, skb,
341 fl4.saddr, fl4.daddr,
343 ip4_dst_hoplimit(&rt->dst),
345 htons(GTP0_PORT), htons(GTP0_PORT),
346 !net_eq(sock_net(gtp->sk1u),
352 static int gtp_genl_fill_echo(struct sk_buff *skb, u32 snd_portid, u32 snd_seq,
353 int flags, u32 type, struct echo_info echo)
357 genlh = genlmsg_put(skb, snd_portid, snd_seq, >p_genl_family, flags,
362 if (nla_put_u32(skb, GTPA_VERSION, echo.gtp_version) ||
363 nla_put_be32(skb, GTPA_PEER_ADDRESS, echo.peer_addr_ip4.s_addr) ||
364 nla_put_be32(skb, GTPA_MS_ADDRESS, echo.ms_addr_ip4.s_addr))
367 genlmsg_end(skb, genlh);
371 genlmsg_cancel(skb, genlh);
375 static int gtp0_handle_echo_resp(struct gtp_dev *gtp, struct sk_buff *skb)
377 struct gtp0_header *gtp0;
378 struct echo_info echo;
383 gtp0 = (struct gtp0_header *)(skb->data + sizeof(struct udphdr));
385 if (!gtp0_validate_echo_hdr(gtp0))
389 echo.ms_addr_ip4.s_addr = iph->daddr;
390 echo.peer_addr_ip4.s_addr = iph->saddr;
391 echo.gtp_version = GTP_V0;
393 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
397 ret = gtp_genl_fill_echo(msg, 0, 0, 0, GTP_CMD_ECHOREQ, echo);
403 return genlmsg_multicast_netns(>p_genl_family, dev_net(gtp->dev),
404 msg, 0, GTP_GENL_MCGRP, GFP_ATOMIC);
407 /* 1 means pass up to the stack, -1 means drop and 0 means decapsulated. */
408 static int gtp0_udp_encap_recv(struct gtp_dev *gtp, struct sk_buff *skb)
410 unsigned int hdrlen = sizeof(struct udphdr) +
411 sizeof(struct gtp0_header);
412 struct gtp0_header *gtp0;
413 struct pdp_ctx *pctx;
415 if (!pskb_may_pull(skb, hdrlen))
418 gtp0 = (struct gtp0_header *)(skb->data + sizeof(struct udphdr));
420 if ((gtp0->flags >> 5) != GTP_V0)
423 /* If the sockets were created in kernel, it means that
424 * there is no daemon running in userspace which would
425 * handle echo request.
427 if (gtp0->type == GTP_ECHO_REQ && gtp->sk_created)
428 return gtp0_send_echo_resp(gtp, skb);
430 if (gtp0->type == GTP_ECHO_RSP && gtp->sk_created)
431 return gtp0_handle_echo_resp(gtp, skb);
433 if (gtp0->type != GTP_TPDU)
436 pctx = gtp0_pdp_find(gtp, be64_to_cpu(gtp0->tid));
438 netdev_dbg(gtp->dev, "No PDP ctx to decap skb=%p\n", skb);
442 return gtp_rx(pctx, skb, hdrlen, gtp->role);
445 /* msg_type has to be GTP_ECHO_REQ or GTP_ECHO_RSP */
446 static void gtp1u_build_echo_msg(struct gtp1_header_long *hdr, __u8 msg_type)
448 int len_pkt, len_hdr;
450 /* S flag must be set to 1 */
451 hdr->flags = 0x32; /* v1, GTP-non-prime. */
452 hdr->type = msg_type;
453 /* 3GPP TS 29.281 5.1 - TEID has to be set to 0 */
456 /* seq, npdu and next should be counted to the length of the GTP packet
457 * that's why szie of gtp1_header should be subtracted,
458 * not size of gtp1_header_long.
461 len_hdr = sizeof(struct gtp1_header);
463 if (msg_type == GTP_ECHO_RSP) {
464 len_pkt = sizeof(struct gtp1u_packet);
465 hdr->length = htons(len_pkt - len_hdr);
467 /* GTP_ECHO_REQ does not carry GTP Information Element,
468 * the why gtp1_header_long is used here.
470 len_pkt = sizeof(struct gtp1_header_long);
471 hdr->length = htons(len_pkt - len_hdr);
475 static int gtp1u_send_echo_resp(struct gtp_dev *gtp, struct sk_buff *skb)
477 struct gtp1_header_long *gtp1u;
478 struct gtp1u_packet *gtp_pkt;
483 gtp1u = (struct gtp1_header_long *)(skb->data + sizeof(struct udphdr));
485 /* 3GPP TS 29.281 5.1 - For the Echo Request, Echo Response,
486 * Error Indication and Supported Extension Headers Notification
487 * messages, the S flag shall be set to 1 and TEID shall be set to 0.
489 if (!(gtp1u->flags & GTP1_F_SEQ) || gtp1u->tid)
492 /* pull GTP and UDP headers */
494 sizeof(struct gtp1_header_long) + sizeof(struct udphdr));
496 gtp_pkt = skb_push(skb, sizeof(struct gtp1u_packet));
497 memset(gtp_pkt, 0, sizeof(struct gtp1u_packet));
499 gtp1u_build_echo_msg(>p_pkt->gtp1u_h, GTP_ECHO_RSP);
501 /* 3GPP TS 29.281 7.7.2 - The Restart Counter value in the
502 * Recovery information element shall not be used, i.e. it shall
503 * be set to zero by the sender and shall be ignored by the receiver.
504 * The Recovery information element is mandatory due to backwards
505 * compatibility reasons.
507 gtp_pkt->ie.tag = GTPIE_RECOVERY;
512 /* find route to the sender,
513 * src address becomes dst address and vice versa.
515 rt = ip4_route_output_gtp(&fl4, gtp->sk1u, iph->saddr, iph->daddr);
517 netdev_dbg(gtp->dev, "no route for echo response from %pI4\n",
522 udp_tunnel_xmit_skb(rt, gtp->sk1u, skb,
523 fl4.saddr, fl4.daddr,
525 ip4_dst_hoplimit(&rt->dst),
527 htons(GTP1U_PORT), htons(GTP1U_PORT),
528 !net_eq(sock_net(gtp->sk1u),
534 static int gtp1u_handle_echo_resp(struct gtp_dev *gtp, struct sk_buff *skb)
536 struct gtp1_header_long *gtp1u;
537 struct echo_info echo;
542 gtp1u = (struct gtp1_header_long *)(skb->data + sizeof(struct udphdr));
544 /* 3GPP TS 29.281 5.1 - For the Echo Request, Echo Response,
545 * Error Indication and Supported Extension Headers Notification
546 * messages, the S flag shall be set to 1 and TEID shall be set to 0.
548 if (!(gtp1u->flags & GTP1_F_SEQ) || gtp1u->tid)
552 echo.ms_addr_ip4.s_addr = iph->daddr;
553 echo.peer_addr_ip4.s_addr = iph->saddr;
554 echo.gtp_version = GTP_V1;
556 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
560 ret = gtp_genl_fill_echo(msg, 0, 0, 0, GTP_CMD_ECHOREQ, echo);
566 return genlmsg_multicast_netns(>p_genl_family, dev_net(gtp->dev),
567 msg, 0, GTP_GENL_MCGRP, GFP_ATOMIC);
570 static int gtp1u_udp_encap_recv(struct gtp_dev *gtp, struct sk_buff *skb)
572 unsigned int hdrlen = sizeof(struct udphdr) +
573 sizeof(struct gtp1_header);
574 struct gtp1_header *gtp1;
575 struct pdp_ctx *pctx;
577 if (!pskb_may_pull(skb, hdrlen))
580 gtp1 = (struct gtp1_header *)(skb->data + sizeof(struct udphdr));
582 if ((gtp1->flags >> 5) != GTP_V1)
585 /* If the sockets were created in kernel, it means that
586 * there is no daemon running in userspace which would
587 * handle echo request.
589 if (gtp1->type == GTP_ECHO_REQ && gtp->sk_created)
590 return gtp1u_send_echo_resp(gtp, skb);
592 if (gtp1->type == GTP_ECHO_RSP && gtp->sk_created)
593 return gtp1u_handle_echo_resp(gtp, skb);
595 if (gtp1->type != GTP_TPDU)
598 /* From 29.060: "This field shall be present if and only if any one or
599 * more of the S, PN and E flags are set.".
601 * If any of the bit is set, then the remaining ones also have to be
604 if (gtp1->flags & GTP1_F_MASK)
607 /* Make sure the header is larger enough, including extensions. */
608 if (!pskb_may_pull(skb, hdrlen))
611 gtp1 = (struct gtp1_header *)(skb->data + sizeof(struct udphdr));
613 pctx = gtp1_pdp_find(gtp, ntohl(gtp1->tid));
615 netdev_dbg(gtp->dev, "No PDP ctx to decap skb=%p\n", skb);
619 return gtp_rx(pctx, skb, hdrlen, gtp->role);
622 static void __gtp_encap_destroy(struct sock *sk)
627 gtp = sk->sk_user_data;
633 WRITE_ONCE(udp_sk(sk)->encap_type, 0);
634 rcu_assign_sk_user_data(sk, NULL);
642 static void gtp_encap_destroy(struct sock *sk)
645 __gtp_encap_destroy(sk);
649 static void gtp_encap_disable_sock(struct sock *sk)
654 __gtp_encap_destroy(sk);
657 static void gtp_encap_disable(struct gtp_dev *gtp)
659 if (gtp->sk_created) {
660 udp_tunnel_sock_release(gtp->sk0->sk_socket);
661 udp_tunnel_sock_release(gtp->sk1u->sk_socket);
662 gtp->sk_created = false;
666 gtp_encap_disable_sock(gtp->sk0);
667 gtp_encap_disable_sock(gtp->sk1u);
671 /* UDP encapsulation receive handler. See net/ipv4/udp.c.
672 * Return codes: 0: success, <0: error, >0: pass up to userspace UDP socket.
674 static int gtp_encap_recv(struct sock *sk, struct sk_buff *skb)
679 gtp = rcu_dereference_sk_user_data(sk);
683 netdev_dbg(gtp->dev, "encap_recv sk=%p\n", sk);
685 switch (READ_ONCE(udp_sk(sk)->encap_type)) {
687 netdev_dbg(gtp->dev, "received GTP0 packet\n");
688 ret = gtp0_udp_encap_recv(gtp, skb);
690 case UDP_ENCAP_GTP1U:
691 netdev_dbg(gtp->dev, "received GTP1U packet\n");
692 ret = gtp1u_udp_encap_recv(gtp, skb);
695 ret = -1; /* Shouldn't happen. */
700 netdev_dbg(gtp->dev, "pass up to the process\n");
705 netdev_dbg(gtp->dev, "GTP packet has been dropped\n");
714 static int gtp_dev_init(struct net_device *dev)
716 struct gtp_dev *gtp = netdev_priv(dev);
720 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
727 static void gtp_dev_uninit(struct net_device *dev)
729 struct gtp_dev *gtp = netdev_priv(dev);
731 gtp_encap_disable(gtp);
732 free_percpu(dev->tstats);
735 static inline void gtp0_push_header(struct sk_buff *skb, struct pdp_ctx *pctx)
737 int payload_len = skb->len;
738 struct gtp0_header *gtp0;
740 gtp0 = skb_push(skb, sizeof(*gtp0));
742 gtp0->flags = 0x1e; /* v0, GTP-non-prime. */
743 gtp0->type = GTP_TPDU;
744 gtp0->length = htons(payload_len);
745 gtp0->seq = htons((atomic_inc_return(&pctx->tx_seq) - 1) % 0xffff);
746 gtp0->flow = htons(pctx->u.v0.flow);
748 gtp0->spare[0] = gtp0->spare[1] = gtp0->spare[2] = 0xff;
749 gtp0->tid = cpu_to_be64(pctx->u.v0.tid);
752 static inline void gtp1_push_header(struct sk_buff *skb, struct pdp_ctx *pctx)
754 int payload_len = skb->len;
755 struct gtp1_header *gtp1;
757 gtp1 = skb_push(skb, sizeof(*gtp1));
759 /* Bits 8 7 6 5 4 3 2 1
760 * +--+--+--+--+--+--+--+--+
761 * |version |PT| 0| E| S|PN|
762 * +--+--+--+--+--+--+--+--+
765 gtp1->flags = 0x30; /* v1, GTP-non-prime. */
766 gtp1->type = GTP_TPDU;
767 gtp1->length = htons(payload_len);
768 gtp1->tid = htonl(pctx->u.v1.o_tei);
770 /* TODO: Support for extension header, sequence number and N-PDU.
771 * Update the length field if any of them is available.
780 struct pdp_ctx *pctx;
781 struct net_device *dev;
785 static void gtp_push_header(struct sk_buff *skb, struct gtp_pktinfo *pktinfo)
787 switch (pktinfo->pctx->gtp_version) {
789 pktinfo->gtph_port = htons(GTP0_PORT);
790 gtp0_push_header(skb, pktinfo->pctx);
793 pktinfo->gtph_port = htons(GTP1U_PORT);
794 gtp1_push_header(skb, pktinfo->pctx);
799 static inline void gtp_set_pktinfo_ipv4(struct gtp_pktinfo *pktinfo,
800 struct sock *sk, struct iphdr *iph,
801 struct pdp_ctx *pctx, struct rtable *rt,
803 struct net_device *dev)
807 pktinfo->pctx = pctx;
813 static int gtp_build_skb_ip4(struct sk_buff *skb, struct net_device *dev,
814 struct gtp_pktinfo *pktinfo)
816 struct gtp_dev *gtp = netdev_priv(dev);
817 struct pdp_ctx *pctx;
824 /* Read the IP destination address and resolve the PDP context.
825 * Prepend PDP header with TEI/TID from PDP ctx.
828 if (gtp->role == GTP_ROLE_SGSN)
829 pctx = ipv4_pdp_find(gtp, iph->saddr);
831 pctx = ipv4_pdp_find(gtp, iph->daddr);
834 netdev_dbg(dev, "no PDP ctx found for %pI4, skip\n",
838 netdev_dbg(dev, "found PDP context %p\n", pctx);
840 rt = ip4_route_output_gtp(&fl4, pctx->sk, pctx->peer_addr_ip4.s_addr,
841 inet_sk(pctx->sk)->inet_saddr);
843 netdev_dbg(dev, "no route to SSGN %pI4\n",
844 &pctx->peer_addr_ip4.s_addr);
845 dev->stats.tx_carrier_errors++;
849 if (rt->dst.dev == dev) {
850 netdev_dbg(dev, "circular route to SSGN %pI4\n",
851 &pctx->peer_addr_ip4.s_addr);
852 dev->stats.collisions++;
856 /* This is similar to tnl_update_pmtu(). */
859 mtu = dst_mtu(&rt->dst) - dev->hard_header_len -
860 sizeof(struct iphdr) - sizeof(struct udphdr);
861 switch (pctx->gtp_version) {
863 mtu -= sizeof(struct gtp0_header);
866 mtu -= sizeof(struct gtp1_header);
870 mtu = dst_mtu(&rt->dst);
873 skb_dst_update_pmtu_no_confirm(skb, mtu);
875 if (iph->frag_off & htons(IP_DF) &&
876 ((!skb_is_gso(skb) && skb->len > mtu) ||
877 (skb_is_gso(skb) && !skb_gso_validate_network_len(skb, mtu)))) {
878 netdev_dbg(dev, "packet too big, fragmentation needed\n");
879 icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
884 gtp_set_pktinfo_ipv4(pktinfo, pctx->sk, iph, pctx, rt, &fl4, dev);
885 gtp_push_header(skb, pktinfo);
894 static netdev_tx_t gtp_dev_xmit(struct sk_buff *skb, struct net_device *dev)
896 unsigned int proto = ntohs(skb->protocol);
897 struct gtp_pktinfo pktinfo;
900 /* Ensure there is sufficient headroom. */
901 if (skb_cow_head(skb, dev->needed_headroom))
904 skb_reset_inner_headers(skb);
906 /* PDP context lookups in gtp_build_skb_*() need rcu read-side lock. */
910 err = gtp_build_skb_ip4(skb, dev, &pktinfo);
923 netdev_dbg(pktinfo.dev, "gtp -> IP src: %pI4 dst: %pI4\n",
924 &pktinfo.iph->saddr, &pktinfo.iph->daddr);
925 udp_tunnel_xmit_skb(pktinfo.rt, pktinfo.sk, skb,
926 pktinfo.fl4.saddr, pktinfo.fl4.daddr,
928 ip4_dst_hoplimit(&pktinfo.rt->dst),
930 pktinfo.gtph_port, pktinfo.gtph_port,
931 !net_eq(sock_net(pktinfo.pctx->sk),
939 dev->stats.tx_errors++;
944 static const struct net_device_ops gtp_netdev_ops = {
945 .ndo_init = gtp_dev_init,
946 .ndo_uninit = gtp_dev_uninit,
947 .ndo_start_xmit = gtp_dev_xmit,
948 .ndo_get_stats64 = dev_get_tstats64,
951 static const struct device_type gtp_type = {
955 static void gtp_link_setup(struct net_device *dev)
957 unsigned int max_gtp_header_len = sizeof(struct iphdr) +
958 sizeof(struct udphdr) +
959 sizeof(struct gtp0_header);
961 dev->netdev_ops = >p_netdev_ops;
962 dev->needs_free_netdev = true;
963 SET_NETDEV_DEVTYPE(dev, >p_type);
965 dev->hard_header_len = 0;
967 dev->mtu = ETH_DATA_LEN - max_gtp_header_len;
969 /* Zero header length. */
970 dev->type = ARPHRD_NONE;
971 dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
973 dev->priv_flags |= IFF_NO_QUEUE;
974 dev->features |= NETIF_F_LLTX;
977 dev->needed_headroom = LL_MAX_HEADER + max_gtp_header_len;
980 static int gtp_hashtable_new(struct gtp_dev *gtp, int hsize);
981 static int gtp_encap_enable(struct gtp_dev *gtp, struct nlattr *data[]);
983 static void gtp_destructor(struct net_device *dev)
985 struct gtp_dev *gtp = netdev_priv(dev);
987 kfree(gtp->addr_hash);
988 kfree(gtp->tid_hash);
991 static struct sock *gtp_create_sock(int type, struct gtp_dev *gtp)
993 struct udp_tunnel_sock_cfg tuncfg = {};
994 struct udp_port_cfg udp_conf = {
995 .local_ip.s_addr = htonl(INADDR_ANY),
998 struct net *net = gtp->net;
1002 if (type == UDP_ENCAP_GTP0)
1003 udp_conf.local_udp_port = htons(GTP0_PORT);
1004 else if (type == UDP_ENCAP_GTP1U)
1005 udp_conf.local_udp_port = htons(GTP1U_PORT);
1007 return ERR_PTR(-EINVAL);
1009 err = udp_sock_create(net, &udp_conf, &sock);
1011 return ERR_PTR(err);
1013 tuncfg.sk_user_data = gtp;
1014 tuncfg.encap_type = type;
1015 tuncfg.encap_rcv = gtp_encap_recv;
1016 tuncfg.encap_destroy = NULL;
1018 setup_udp_tunnel_sock(net, sock, &tuncfg);
1023 static int gtp_create_sockets(struct gtp_dev *gtp, struct nlattr *data[])
1025 struct sock *sk1u = NULL;
1026 struct sock *sk0 = NULL;
1028 sk0 = gtp_create_sock(UDP_ENCAP_GTP0, gtp);
1030 return PTR_ERR(sk0);
1032 sk1u = gtp_create_sock(UDP_ENCAP_GTP1U, gtp);
1034 udp_tunnel_sock_release(sk0->sk_socket);
1035 return PTR_ERR(sk1u);
1038 gtp->sk_created = true;
1045 static int gtp_newlink(struct net *src_net, struct net_device *dev,
1046 struct nlattr *tb[], struct nlattr *data[],
1047 struct netlink_ext_ack *extack)
1049 unsigned int role = GTP_ROLE_GGSN;
1050 struct gtp_dev *gtp;
1054 gtp = netdev_priv(dev);
1056 if (!data[IFLA_GTP_PDP_HASHSIZE]) {
1059 hashsize = nla_get_u32(data[IFLA_GTP_PDP_HASHSIZE]);
1064 if (data[IFLA_GTP_ROLE]) {
1065 role = nla_get_u32(data[IFLA_GTP_ROLE]);
1066 if (role > GTP_ROLE_SGSN)
1071 if (!data[IFLA_GTP_RESTART_COUNT])
1072 gtp->restart_count = 0;
1074 gtp->restart_count = nla_get_u8(data[IFLA_GTP_RESTART_COUNT]);
1078 err = gtp_hashtable_new(gtp, hashsize);
1082 if (data[IFLA_GTP_CREATE_SOCKETS])
1083 err = gtp_create_sockets(gtp, data);
1085 err = gtp_encap_enable(gtp, data);
1089 err = register_netdevice(dev);
1091 netdev_dbg(dev, "failed to register new netdev %d\n", err);
1095 gn = net_generic(dev_net(dev), gtp_net_id);
1096 list_add_rcu(>p->list, &gn->gtp_dev_list);
1097 dev->priv_destructor = gtp_destructor;
1099 netdev_dbg(dev, "registered new GTP interface\n");
1104 gtp_encap_disable(gtp);
1106 kfree(gtp->addr_hash);
1107 kfree(gtp->tid_hash);
1111 static void gtp_dellink(struct net_device *dev, struct list_head *head)
1113 struct gtp_dev *gtp = netdev_priv(dev);
1114 struct hlist_node *next;
1115 struct pdp_ctx *pctx;
1118 for (i = 0; i < gtp->hash_size; i++)
1119 hlist_for_each_entry_safe(pctx, next, >p->tid_hash[i], hlist_tid)
1120 pdp_context_delete(pctx);
1122 list_del_rcu(>p->list);
1123 unregister_netdevice_queue(dev, head);
1126 static const struct nla_policy gtp_policy[IFLA_GTP_MAX + 1] = {
1127 [IFLA_GTP_FD0] = { .type = NLA_U32 },
1128 [IFLA_GTP_FD1] = { .type = NLA_U32 },
1129 [IFLA_GTP_PDP_HASHSIZE] = { .type = NLA_U32 },
1130 [IFLA_GTP_ROLE] = { .type = NLA_U32 },
1131 [IFLA_GTP_CREATE_SOCKETS] = { .type = NLA_U8 },
1132 [IFLA_GTP_RESTART_COUNT] = { .type = NLA_U8 },
1135 static int gtp_validate(struct nlattr *tb[], struct nlattr *data[],
1136 struct netlink_ext_ack *extack)
1144 static size_t gtp_get_size(const struct net_device *dev)
1146 return nla_total_size(sizeof(__u32)) + /* IFLA_GTP_PDP_HASHSIZE */
1147 nla_total_size(sizeof(__u32)) + /* IFLA_GTP_ROLE */
1148 nla_total_size(sizeof(__u8)); /* IFLA_GTP_RESTART_COUNT */
1151 static int gtp_fill_info(struct sk_buff *skb, const struct net_device *dev)
1153 struct gtp_dev *gtp = netdev_priv(dev);
1155 if (nla_put_u32(skb, IFLA_GTP_PDP_HASHSIZE, gtp->hash_size))
1156 goto nla_put_failure;
1157 if (nla_put_u32(skb, IFLA_GTP_ROLE, gtp->role))
1158 goto nla_put_failure;
1159 if (nla_put_u8(skb, IFLA_GTP_RESTART_COUNT, gtp->restart_count))
1160 goto nla_put_failure;
1168 static struct rtnl_link_ops gtp_link_ops __read_mostly = {
1170 .maxtype = IFLA_GTP_MAX,
1171 .policy = gtp_policy,
1172 .priv_size = sizeof(struct gtp_dev),
1173 .setup = gtp_link_setup,
1174 .validate = gtp_validate,
1175 .newlink = gtp_newlink,
1176 .dellink = gtp_dellink,
1177 .get_size = gtp_get_size,
1178 .fill_info = gtp_fill_info,
1181 static int gtp_hashtable_new(struct gtp_dev *gtp, int hsize)
1185 gtp->addr_hash = kmalloc_array(hsize, sizeof(struct hlist_head),
1186 GFP_KERNEL | __GFP_NOWARN);
1187 if (gtp->addr_hash == NULL)
1190 gtp->tid_hash = kmalloc_array(hsize, sizeof(struct hlist_head),
1191 GFP_KERNEL | __GFP_NOWARN);
1192 if (gtp->tid_hash == NULL)
1195 gtp->hash_size = hsize;
1197 for (i = 0; i < hsize; i++) {
1198 INIT_HLIST_HEAD(>p->addr_hash[i]);
1199 INIT_HLIST_HEAD(>p->tid_hash[i]);
1203 kfree(gtp->addr_hash);
1207 static struct sock *gtp_encap_enable_socket(int fd, int type,
1208 struct gtp_dev *gtp)
1210 struct udp_tunnel_sock_cfg tuncfg = {NULL};
1211 struct socket *sock;
1215 pr_debug("enable gtp on %d, %d\n", fd, type);
1217 sock = sockfd_lookup(fd, &err);
1219 pr_debug("gtp socket fd=%d not found\n", fd);
1224 if (sk->sk_protocol != IPPROTO_UDP ||
1225 sk->sk_type != SOCK_DGRAM ||
1226 (sk->sk_family != AF_INET && sk->sk_family != AF_INET6)) {
1227 pr_debug("socket fd=%d not UDP\n", fd);
1228 sk = ERR_PTR(-EINVAL);
1233 if (sk->sk_user_data) {
1234 sk = ERR_PTR(-EBUSY);
1240 tuncfg.sk_user_data = gtp;
1241 tuncfg.encap_type = type;
1242 tuncfg.encap_rcv = gtp_encap_recv;
1243 tuncfg.encap_destroy = gtp_encap_destroy;
1245 setup_udp_tunnel_sock(sock_net(sock->sk), sock, &tuncfg);
1248 release_sock(sock->sk);
1254 static int gtp_encap_enable(struct gtp_dev *gtp, struct nlattr *data[])
1256 struct sock *sk1u = NULL;
1257 struct sock *sk0 = NULL;
1259 if (!data[IFLA_GTP_FD0] && !data[IFLA_GTP_FD1])
1262 if (data[IFLA_GTP_FD0]) {
1263 u32 fd0 = nla_get_u32(data[IFLA_GTP_FD0]);
1265 sk0 = gtp_encap_enable_socket(fd0, UDP_ENCAP_GTP0, gtp);
1267 return PTR_ERR(sk0);
1270 if (data[IFLA_GTP_FD1]) {
1271 u32 fd1 = nla_get_u32(data[IFLA_GTP_FD1]);
1273 sk1u = gtp_encap_enable_socket(fd1, UDP_ENCAP_GTP1U, gtp);
1275 gtp_encap_disable_sock(sk0);
1276 return PTR_ERR(sk1u);
1286 static struct gtp_dev *gtp_find_dev(struct net *src_net, struct nlattr *nla[])
1288 struct gtp_dev *gtp = NULL;
1289 struct net_device *dev;
1292 /* Examine the link attributes and figure out which network namespace
1293 * we are talking about.
1295 if (nla[GTPA_NET_NS_FD])
1296 net = get_net_ns_by_fd(nla_get_u32(nla[GTPA_NET_NS_FD]));
1298 net = get_net(src_net);
1303 /* Check if there's an existing gtpX device to configure */
1304 dev = dev_get_by_index_rcu(net, nla_get_u32(nla[GTPA_LINK]));
1305 if (dev && dev->netdev_ops == >p_netdev_ops)
1306 gtp = netdev_priv(dev);
1312 static void ipv4_pdp_fill(struct pdp_ctx *pctx, struct genl_info *info)
1314 pctx->gtp_version = nla_get_u32(info->attrs[GTPA_VERSION]);
1316 pctx->peer_addr_ip4.s_addr =
1317 nla_get_be32(info->attrs[GTPA_PEER_ADDRESS]);
1318 pctx->ms_addr_ip4.s_addr =
1319 nla_get_be32(info->attrs[GTPA_MS_ADDRESS]);
1321 switch (pctx->gtp_version) {
1323 /* According to TS 09.60, sections 7.5.1 and 7.5.2, the flow
1324 * label needs to be the same for uplink and downlink packets,
1325 * so let's annotate this.
1327 pctx->u.v0.tid = nla_get_u64(info->attrs[GTPA_TID]);
1328 pctx->u.v0.flow = nla_get_u16(info->attrs[GTPA_FLOW]);
1331 pctx->u.v1.i_tei = nla_get_u32(info->attrs[GTPA_I_TEI]);
1332 pctx->u.v1.o_tei = nla_get_u32(info->attrs[GTPA_O_TEI]);
1339 static struct pdp_ctx *gtp_pdp_add(struct gtp_dev *gtp, struct sock *sk,
1340 struct genl_info *info)
1342 struct pdp_ctx *pctx, *pctx_tid = NULL;
1343 struct net_device *dev = gtp->dev;
1344 u32 hash_ms, hash_tid = 0;
1345 unsigned int version;
1349 ms_addr = nla_get_be32(info->attrs[GTPA_MS_ADDRESS]);
1350 hash_ms = ipv4_hashfn(ms_addr) % gtp->hash_size;
1351 version = nla_get_u32(info->attrs[GTPA_VERSION]);
1353 pctx = ipv4_pdp_find(gtp, ms_addr);
1356 if (version == GTP_V0)
1357 pctx_tid = gtp0_pdp_find(gtp,
1358 nla_get_u64(info->attrs[GTPA_TID]));
1359 else if (version == GTP_V1)
1360 pctx_tid = gtp1_pdp_find(gtp,
1361 nla_get_u32(info->attrs[GTPA_I_TEI]));
1366 if (info->nlhdr->nlmsg_flags & NLM_F_EXCL)
1367 return ERR_PTR(-EEXIST);
1368 if (info->nlhdr->nlmsg_flags & NLM_F_REPLACE)
1369 return ERR_PTR(-EOPNOTSUPP);
1371 if (pctx && pctx_tid)
1372 return ERR_PTR(-EEXIST);
1376 ipv4_pdp_fill(pctx, info);
1378 if (pctx->gtp_version == GTP_V0)
1379 netdev_dbg(dev, "GTPv0-U: update tunnel id = %llx (pdp %p)\n",
1380 pctx->u.v0.tid, pctx);
1381 else if (pctx->gtp_version == GTP_V1)
1382 netdev_dbg(dev, "GTPv1-U: update tunnel id = %x/%x (pdp %p)\n",
1383 pctx->u.v1.i_tei, pctx->u.v1.o_tei, pctx);
1389 pctx = kmalloc(sizeof(*pctx), GFP_ATOMIC);
1391 return ERR_PTR(-ENOMEM);
1395 pctx->dev = gtp->dev;
1396 ipv4_pdp_fill(pctx, info);
1397 atomic_set(&pctx->tx_seq, 0);
1399 switch (pctx->gtp_version) {
1401 /* TS 09.60: "The flow label identifies unambiguously a GTP
1402 * flow.". We use the tid for this instead, I cannot find a
1403 * situation in which this doesn't unambiguosly identify the
1406 hash_tid = gtp0_hashfn(pctx->u.v0.tid) % gtp->hash_size;
1409 hash_tid = gtp1u_hashfn(pctx->u.v1.i_tei) % gtp->hash_size;
1413 hlist_add_head_rcu(&pctx->hlist_addr, >p->addr_hash[hash_ms]);
1414 hlist_add_head_rcu(&pctx->hlist_tid, >p->tid_hash[hash_tid]);
1416 switch (pctx->gtp_version) {
1418 netdev_dbg(dev, "GTPv0-U: new PDP ctx id=%llx ssgn=%pI4 ms=%pI4 (pdp=%p)\n",
1419 pctx->u.v0.tid, &pctx->peer_addr_ip4,
1420 &pctx->ms_addr_ip4, pctx);
1423 netdev_dbg(dev, "GTPv1-U: new PDP ctx id=%x/%x ssgn=%pI4 ms=%pI4 (pdp=%p)\n",
1424 pctx->u.v1.i_tei, pctx->u.v1.o_tei,
1425 &pctx->peer_addr_ip4, &pctx->ms_addr_ip4, pctx);
1432 static void pdp_context_free(struct rcu_head *head)
1434 struct pdp_ctx *pctx = container_of(head, struct pdp_ctx, rcu_head);
1440 static void pdp_context_delete(struct pdp_ctx *pctx)
1442 hlist_del_rcu(&pctx->hlist_tid);
1443 hlist_del_rcu(&pctx->hlist_addr);
1444 call_rcu(&pctx->rcu_head, pdp_context_free);
1447 static int gtp_tunnel_notify(struct pdp_ctx *pctx, u8 cmd, gfp_t allocation);
1449 static int gtp_genl_new_pdp(struct sk_buff *skb, struct genl_info *info)
1451 unsigned int version;
1452 struct pdp_ctx *pctx;
1453 struct gtp_dev *gtp;
1457 if (!info->attrs[GTPA_VERSION] ||
1458 !info->attrs[GTPA_LINK] ||
1459 !info->attrs[GTPA_PEER_ADDRESS] ||
1460 !info->attrs[GTPA_MS_ADDRESS])
1463 version = nla_get_u32(info->attrs[GTPA_VERSION]);
1467 if (!info->attrs[GTPA_TID] ||
1468 !info->attrs[GTPA_FLOW])
1472 if (!info->attrs[GTPA_I_TEI] ||
1473 !info->attrs[GTPA_O_TEI])
1483 gtp = gtp_find_dev(sock_net(skb->sk), info->attrs);
1489 if (version == GTP_V0)
1491 else if (version == GTP_V1)
1501 pctx = gtp_pdp_add(gtp, sk, info);
1503 err = PTR_ERR(pctx);
1505 gtp_tunnel_notify(pctx, GTP_CMD_NEWPDP, GFP_KERNEL);
1514 static struct pdp_ctx *gtp_find_pdp_by_link(struct net *net,
1515 struct nlattr *nla[])
1517 struct gtp_dev *gtp;
1519 gtp = gtp_find_dev(net, nla);
1521 return ERR_PTR(-ENODEV);
1523 if (nla[GTPA_MS_ADDRESS]) {
1524 __be32 ip = nla_get_be32(nla[GTPA_MS_ADDRESS]);
1526 return ipv4_pdp_find(gtp, ip);
1527 } else if (nla[GTPA_VERSION]) {
1528 u32 gtp_version = nla_get_u32(nla[GTPA_VERSION]);
1530 if (gtp_version == GTP_V0 && nla[GTPA_TID])
1531 return gtp0_pdp_find(gtp, nla_get_u64(nla[GTPA_TID]));
1532 else if (gtp_version == GTP_V1 && nla[GTPA_I_TEI])
1533 return gtp1_pdp_find(gtp, nla_get_u32(nla[GTPA_I_TEI]));
1536 return ERR_PTR(-EINVAL);
1539 static struct pdp_ctx *gtp_find_pdp(struct net *net, struct nlattr *nla[])
1541 struct pdp_ctx *pctx;
1544 pctx = gtp_find_pdp_by_link(net, nla);
1546 pctx = ERR_PTR(-EINVAL);
1549 pctx = ERR_PTR(-ENOENT);
1554 static int gtp_genl_del_pdp(struct sk_buff *skb, struct genl_info *info)
1556 struct pdp_ctx *pctx;
1559 if (!info->attrs[GTPA_VERSION])
1564 pctx = gtp_find_pdp(sock_net(skb->sk), info->attrs);
1566 err = PTR_ERR(pctx);
1570 if (pctx->gtp_version == GTP_V0)
1571 netdev_dbg(pctx->dev, "GTPv0-U: deleting tunnel id = %llx (pdp %p)\n",
1572 pctx->u.v0.tid, pctx);
1573 else if (pctx->gtp_version == GTP_V1)
1574 netdev_dbg(pctx->dev, "GTPv1-U: deleting tunnel id = %x/%x (pdp %p)\n",
1575 pctx->u.v1.i_tei, pctx->u.v1.o_tei, pctx);
1577 gtp_tunnel_notify(pctx, GTP_CMD_DELPDP, GFP_ATOMIC);
1578 pdp_context_delete(pctx);
1585 static int gtp_genl_fill_info(struct sk_buff *skb, u32 snd_portid, u32 snd_seq,
1586 int flags, u32 type, struct pdp_ctx *pctx)
1590 genlh = genlmsg_put(skb, snd_portid, snd_seq, >p_genl_family, flags,
1595 if (nla_put_u32(skb, GTPA_VERSION, pctx->gtp_version) ||
1596 nla_put_u32(skb, GTPA_LINK, pctx->dev->ifindex) ||
1597 nla_put_be32(skb, GTPA_PEER_ADDRESS, pctx->peer_addr_ip4.s_addr) ||
1598 nla_put_be32(skb, GTPA_MS_ADDRESS, pctx->ms_addr_ip4.s_addr))
1599 goto nla_put_failure;
1601 switch (pctx->gtp_version) {
1603 if (nla_put_u64_64bit(skb, GTPA_TID, pctx->u.v0.tid, GTPA_PAD) ||
1604 nla_put_u16(skb, GTPA_FLOW, pctx->u.v0.flow))
1605 goto nla_put_failure;
1608 if (nla_put_u32(skb, GTPA_I_TEI, pctx->u.v1.i_tei) ||
1609 nla_put_u32(skb, GTPA_O_TEI, pctx->u.v1.o_tei))
1610 goto nla_put_failure;
1613 genlmsg_end(skb, genlh);
1618 genlmsg_cancel(skb, genlh);
1622 static int gtp_tunnel_notify(struct pdp_ctx *pctx, u8 cmd, gfp_t allocation)
1624 struct sk_buff *msg;
1627 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, allocation);
1631 ret = gtp_genl_fill_info(msg, 0, 0, 0, cmd, pctx);
1637 ret = genlmsg_multicast_netns(>p_genl_family, dev_net(pctx->dev), msg,
1638 0, GTP_GENL_MCGRP, GFP_ATOMIC);
1642 static int gtp_genl_get_pdp(struct sk_buff *skb, struct genl_info *info)
1644 struct pdp_ctx *pctx = NULL;
1645 struct sk_buff *skb2;
1648 if (!info->attrs[GTPA_VERSION])
1653 pctx = gtp_find_pdp(sock_net(skb->sk), info->attrs);
1655 err = PTR_ERR(pctx);
1659 skb2 = genlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC);
1665 err = gtp_genl_fill_info(skb2, NETLINK_CB(skb).portid, info->snd_seq,
1666 0, info->nlhdr->nlmsg_type, pctx);
1668 goto err_unlock_free;
1671 return genlmsg_unicast(genl_info_net(info), skb2, info->snd_portid);
1680 static int gtp_genl_dump_pdp(struct sk_buff *skb,
1681 struct netlink_callback *cb)
1683 struct gtp_dev *last_gtp = (struct gtp_dev *)cb->args[2], *gtp;
1684 int i, j, bucket = cb->args[0], skip = cb->args[1];
1685 struct net *net = sock_net(skb->sk);
1686 struct pdp_ctx *pctx;
1689 gn = net_generic(net, gtp_net_id);
1695 list_for_each_entry_rcu(gtp, &gn->gtp_dev_list, list) {
1696 if (last_gtp && last_gtp != gtp)
1701 for (i = bucket; i < gtp->hash_size; i++) {
1703 hlist_for_each_entry_rcu(pctx, >p->tid_hash[i],
1706 gtp_genl_fill_info(skb,
1707 NETLINK_CB(cb->skb).portid,
1710 cb->nlh->nlmsg_type, pctx)) {
1713 cb->args[2] = (unsigned long)gtp;
1728 static int gtp_genl_send_echo_req(struct sk_buff *skb, struct genl_info *info)
1730 struct sk_buff *skb_to_send;
1731 __be32 src_ip, dst_ip;
1732 unsigned int version;
1733 struct gtp_dev *gtp;
1740 if (!info->attrs[GTPA_VERSION] ||
1741 !info->attrs[GTPA_LINK] ||
1742 !info->attrs[GTPA_PEER_ADDRESS] ||
1743 !info->attrs[GTPA_MS_ADDRESS])
1746 version = nla_get_u32(info->attrs[GTPA_VERSION]);
1747 dst_ip = nla_get_be32(info->attrs[GTPA_PEER_ADDRESS]);
1748 src_ip = nla_get_be32(info->attrs[GTPA_MS_ADDRESS]);
1750 gtp = gtp_find_dev(sock_net(skb->sk), info->attrs);
1754 if (!gtp->sk_created)
1756 if (!(gtp->dev->flags & IFF_UP))
1759 if (version == GTP_V0) {
1760 struct gtp0_header *gtp0_h;
1762 len = LL_RESERVED_SPACE(gtp->dev) + sizeof(struct gtp0_header) +
1763 sizeof(struct iphdr) + sizeof(struct udphdr);
1765 skb_to_send = netdev_alloc_skb_ip_align(gtp->dev, len);
1770 port = htons(GTP0_PORT);
1772 gtp0_h = skb_push(skb_to_send, sizeof(struct gtp0_header));
1773 memset(gtp0_h, 0, sizeof(struct gtp0_header));
1774 gtp0_build_echo_msg(gtp0_h, GTP_ECHO_REQ);
1775 } else if (version == GTP_V1) {
1776 struct gtp1_header_long *gtp1u_h;
1778 len = LL_RESERVED_SPACE(gtp->dev) +
1779 sizeof(struct gtp1_header_long) +
1780 sizeof(struct iphdr) + sizeof(struct udphdr);
1782 skb_to_send = netdev_alloc_skb_ip_align(gtp->dev, len);
1787 port = htons(GTP1U_PORT);
1789 gtp1u_h = skb_push(skb_to_send,
1790 sizeof(struct gtp1_header_long));
1791 memset(gtp1u_h, 0, sizeof(struct gtp1_header_long));
1792 gtp1u_build_echo_msg(gtp1u_h, GTP_ECHO_REQ);
1797 rt = ip4_route_output_gtp(&fl4, sk, dst_ip, src_ip);
1799 netdev_dbg(gtp->dev, "no route for echo request to %pI4\n",
1801 kfree_skb(skb_to_send);
1805 udp_tunnel_xmit_skb(rt, sk, skb_to_send,
1806 fl4.saddr, fl4.daddr,
1808 ip4_dst_hoplimit(&rt->dst),
1811 !net_eq(sock_net(sk),
1817 static const struct nla_policy gtp_genl_policy[GTPA_MAX + 1] = {
1818 [GTPA_LINK] = { .type = NLA_U32, },
1819 [GTPA_VERSION] = { .type = NLA_U32, },
1820 [GTPA_TID] = { .type = NLA_U64, },
1821 [GTPA_PEER_ADDRESS] = { .type = NLA_U32, },
1822 [GTPA_MS_ADDRESS] = { .type = NLA_U32, },
1823 [GTPA_FLOW] = { .type = NLA_U16, },
1824 [GTPA_NET_NS_FD] = { .type = NLA_U32, },
1825 [GTPA_I_TEI] = { .type = NLA_U32, },
1826 [GTPA_O_TEI] = { .type = NLA_U32, },
1829 static const struct genl_small_ops gtp_genl_ops[] = {
1831 .cmd = GTP_CMD_NEWPDP,
1832 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
1833 .doit = gtp_genl_new_pdp,
1834 .flags = GENL_ADMIN_PERM,
1837 .cmd = GTP_CMD_DELPDP,
1838 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
1839 .doit = gtp_genl_del_pdp,
1840 .flags = GENL_ADMIN_PERM,
1843 .cmd = GTP_CMD_GETPDP,
1844 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
1845 .doit = gtp_genl_get_pdp,
1846 .dumpit = gtp_genl_dump_pdp,
1847 .flags = GENL_ADMIN_PERM,
1850 .cmd = GTP_CMD_ECHOREQ,
1851 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
1852 .doit = gtp_genl_send_echo_req,
1853 .flags = GENL_ADMIN_PERM,
1857 static struct genl_family gtp_genl_family __ro_after_init = {
1861 .maxattr = GTPA_MAX,
1862 .policy = gtp_genl_policy,
1864 .module = THIS_MODULE,
1865 .small_ops = gtp_genl_ops,
1866 .n_small_ops = ARRAY_SIZE(gtp_genl_ops),
1867 .resv_start_op = GTP_CMD_ECHOREQ + 1,
1868 .mcgrps = gtp_genl_mcgrps,
1869 .n_mcgrps = ARRAY_SIZE(gtp_genl_mcgrps),
1872 static int __net_init gtp_net_init(struct net *net)
1874 struct gtp_net *gn = net_generic(net, gtp_net_id);
1876 INIT_LIST_HEAD(&gn->gtp_dev_list);
1880 static void __net_exit gtp_net_exit(struct net *net)
1882 struct gtp_net *gn = net_generic(net, gtp_net_id);
1883 struct gtp_dev *gtp;
1887 list_for_each_entry(gtp, &gn->gtp_dev_list, list)
1888 gtp_dellink(gtp->dev, &list);
1890 unregister_netdevice_many(&list);
1894 static struct pernet_operations gtp_net_ops = {
1895 .init = gtp_net_init,
1896 .exit = gtp_net_exit,
1898 .size = sizeof(struct gtp_net),
1901 static int __init gtp_init(void)
1905 get_random_bytes(>p_h_initval, sizeof(gtp_h_initval));
1907 err = register_pernet_subsys(>p_net_ops);
1911 err = rtnl_link_register(>p_link_ops);
1913 goto unreg_pernet_subsys;
1915 err = genl_register_family(>p_genl_family);
1917 goto unreg_rtnl_link;
1919 pr_info("GTP module loaded (pdp ctx size %zd bytes)\n",
1920 sizeof(struct pdp_ctx));
1924 rtnl_link_unregister(>p_link_ops);
1925 unreg_pernet_subsys:
1926 unregister_pernet_subsys(>p_net_ops);
1928 pr_err("error loading GTP module loaded\n");
1931 late_initcall(gtp_init);
1933 static void __exit gtp_fini(void)
1935 genl_unregister_family(>p_genl_family);
1936 rtnl_link_unregister(>p_link_ops);
1937 unregister_pernet_subsys(>p_net_ops);
1939 pr_info("GTP module unloaded\n");
1941 module_exit(gtp_fini);
1943 MODULE_LICENSE("GPL");
1944 MODULE_AUTHOR("Harald Welte <hwelte@sysmocom.de>");
1945 MODULE_DESCRIPTION("Interface driver for GTP encapsulated traffic");
1946 MODULE_ALIAS_RTNL_LINK("gtp");
1947 MODULE_ALIAS_GENL_FAMILY("gtp");