1 /* GTP according to GSM TS 09.60 / 3GPP TS 29.060
3 * (C) 2012-2014 by sysmocom - s.f.m.c. GmbH
4 * (C) 2016 by Pablo Neira Ayuso <pablo@netfilter.org>
6 * Author: Harald Welte <hwelte@sysmocom.de>
7 * Pablo Neira Ayuso <pablo@netfilter.org>
8 * Andreas Schultz <aschultz@travelping.com>
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License
12 * as published by the Free Software Foundation; either version
13 * 2 of the License, or (at your option) any later version.
16 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
18 #include <linux/module.h>
19 #include <linux/skbuff.h>
20 #include <linux/udp.h>
21 #include <linux/rculist.h>
22 #include <linux/jhash.h>
23 #include <linux/if_tunnel.h>
24 #include <linux/net.h>
25 #include <linux/file.h>
26 #include <linux/gtp.h>
28 #include <net/net_namespace.h>
29 #include <net/protocol.h>
32 #include <net/udp_tunnel.h>
35 #include <net/genetlink.h>
36 #include <net/netns/generic.h>
39 /* An active session for the subscriber. */
41 struct hlist_node hlist_tid;
42 struct hlist_node hlist_addr;
57 struct in_addr ms_addr_ip4;
58 struct in_addr peer_addr_ip4;
61 struct net_device *dev;
64 struct rcu_head rcu_head;
67 /* One instance of the GTP device. */
69 struct list_head list;
74 struct net_device *dev;
77 unsigned int hash_size;
78 struct hlist_head *tid_hash;
79 struct hlist_head *addr_hash;
82 static unsigned int gtp_net_id __read_mostly;
85 struct list_head gtp_dev_list;
88 static u32 gtp_h_initval;
90 static void pdp_context_delete(struct pdp_ctx *pctx);
92 static inline u32 gtp0_hashfn(u64 tid)
94 u32 *tid32 = (u32 *) &tid;
95 return jhash_2words(tid32[0], tid32[1], gtp_h_initval);
98 static inline u32 gtp1u_hashfn(u32 tid)
100 return jhash_1word(tid, gtp_h_initval);
103 static inline u32 ipv4_hashfn(__be32 ip)
105 return jhash_1word((__force u32)ip, gtp_h_initval);
108 /* Resolve a PDP context structure based on the 64bit TID. */
109 static struct pdp_ctx *gtp0_pdp_find(struct gtp_dev *gtp, u64 tid)
111 struct hlist_head *head;
114 head = >p->tid_hash[gtp0_hashfn(tid) % gtp->hash_size];
116 hlist_for_each_entry_rcu(pdp, head, hlist_tid) {
117 if (pdp->gtp_version == GTP_V0 &&
118 pdp->u.v0.tid == tid)
124 /* Resolve a PDP context structure based on the 32bit TEI. */
125 static struct pdp_ctx *gtp1_pdp_find(struct gtp_dev *gtp, u32 tid)
127 struct hlist_head *head;
130 head = >p->tid_hash[gtp1u_hashfn(tid) % gtp->hash_size];
132 hlist_for_each_entry_rcu(pdp, head, hlist_tid) {
133 if (pdp->gtp_version == GTP_V1 &&
134 pdp->u.v1.i_tei == tid)
140 /* Resolve a PDP context based on IPv4 address of MS. */
141 static struct pdp_ctx *ipv4_pdp_find(struct gtp_dev *gtp, __be32 ms_addr)
143 struct hlist_head *head;
146 head = >p->addr_hash[ipv4_hashfn(ms_addr) % gtp->hash_size];
148 hlist_for_each_entry_rcu(pdp, head, hlist_addr) {
149 if (pdp->af == AF_INET &&
150 pdp->ms_addr_ip4.s_addr == ms_addr)
157 static bool gtp_check_ms_ipv4(struct sk_buff *skb, struct pdp_ctx *pctx,
158 unsigned int hdrlen, unsigned int role)
162 if (!pskb_may_pull(skb, hdrlen + sizeof(struct iphdr)))
165 iph = (struct iphdr *)(skb->data + hdrlen);
167 if (role == GTP_ROLE_SGSN)
168 return iph->daddr == pctx->ms_addr_ip4.s_addr;
170 return iph->saddr == pctx->ms_addr_ip4.s_addr;
173 /* Check if the inner IP address in this packet is assigned to any
174 * existing mobile subscriber.
176 static bool gtp_check_ms(struct sk_buff *skb, struct pdp_ctx *pctx,
177 unsigned int hdrlen, unsigned int role)
179 switch (ntohs(skb->protocol)) {
181 return gtp_check_ms_ipv4(skb, pctx, hdrlen, role);
186 static int gtp_rx(struct pdp_ctx *pctx, struct sk_buff *skb,
187 unsigned int hdrlen, unsigned int role)
189 struct pcpu_sw_netstats *stats;
191 if (!gtp_check_ms(skb, pctx, hdrlen, role)) {
192 netdev_dbg(pctx->dev, "No PDP ctx for this MS\n");
196 /* Get rid of the GTP + UDP headers. */
197 if (iptunnel_pull_header(skb, hdrlen, skb->protocol,
198 !net_eq(sock_net(pctx->sk), dev_net(pctx->dev))))
201 netdev_dbg(pctx->dev, "forwarding packet from GGSN to uplink\n");
203 /* Now that the UDP and the GTP header have been removed, set up the
204 * new network header. This is required by the upper layer to
205 * calculate the transport header.
207 skb_reset_network_header(skb);
209 skb->dev = pctx->dev;
211 stats = this_cpu_ptr(pctx->dev->tstats);
212 u64_stats_update_begin(&stats->syncp);
214 stats->rx_bytes += skb->len;
215 u64_stats_update_end(&stats->syncp);
221 /* 1 means pass up to the stack, -1 means drop and 0 means decapsulated. */
222 static int gtp0_udp_encap_recv(struct gtp_dev *gtp, struct sk_buff *skb)
224 unsigned int hdrlen = sizeof(struct udphdr) +
225 sizeof(struct gtp0_header);
226 struct gtp0_header *gtp0;
227 struct pdp_ctx *pctx;
229 if (!pskb_may_pull(skb, hdrlen))
232 gtp0 = (struct gtp0_header *)(skb->data + sizeof(struct udphdr));
234 if ((gtp0->flags >> 5) != GTP_V0)
237 if (gtp0->type != GTP_TPDU)
240 pctx = gtp0_pdp_find(gtp, be64_to_cpu(gtp0->tid));
242 netdev_dbg(gtp->dev, "No PDP ctx to decap skb=%p\n", skb);
246 return gtp_rx(pctx, skb, hdrlen, gtp->role);
249 static int gtp1u_udp_encap_recv(struct gtp_dev *gtp, struct sk_buff *skb)
251 unsigned int hdrlen = sizeof(struct udphdr) +
252 sizeof(struct gtp1_header);
253 struct gtp1_header *gtp1;
254 struct pdp_ctx *pctx;
256 if (!pskb_may_pull(skb, hdrlen))
259 gtp1 = (struct gtp1_header *)(skb->data + sizeof(struct udphdr));
261 if ((gtp1->flags >> 5) != GTP_V1)
264 if (gtp1->type != GTP_TPDU)
267 /* From 29.060: "This field shall be present if and only if any one or
268 * more of the S, PN and E flags are set.".
270 * If any of the bit is set, then the remaining ones also have to be
273 if (gtp1->flags & GTP1_F_MASK)
276 /* Make sure the header is larger enough, including extensions. */
277 if (!pskb_may_pull(skb, hdrlen))
280 gtp1 = (struct gtp1_header *)(skb->data + sizeof(struct udphdr));
282 pctx = gtp1_pdp_find(gtp, ntohl(gtp1->tid));
284 netdev_dbg(gtp->dev, "No PDP ctx to decap skb=%p\n", skb);
288 return gtp_rx(pctx, skb, hdrlen, gtp->role);
291 static void __gtp_encap_destroy(struct sock *sk)
296 gtp = sk->sk_user_data;
302 udp_sk(sk)->encap_type = 0;
303 rcu_assign_sk_user_data(sk, NULL);
311 static void gtp_encap_destroy(struct sock *sk)
314 __gtp_encap_destroy(sk);
318 static void gtp_encap_disable_sock(struct sock *sk)
323 __gtp_encap_destroy(sk);
326 static void gtp_encap_disable(struct gtp_dev *gtp)
328 gtp_encap_disable_sock(gtp->sk0);
329 gtp_encap_disable_sock(gtp->sk1u);
332 /* UDP encapsulation receive handler. See net/ipv4/udp.c.
333 * Return codes: 0: success, <0: error, >0: pass up to userspace UDP socket.
335 static int gtp_encap_recv(struct sock *sk, struct sk_buff *skb)
340 gtp = rcu_dereference_sk_user_data(sk);
344 netdev_dbg(gtp->dev, "encap_recv sk=%p\n", sk);
346 switch (udp_sk(sk)->encap_type) {
348 netdev_dbg(gtp->dev, "received GTP0 packet\n");
349 ret = gtp0_udp_encap_recv(gtp, skb);
351 case UDP_ENCAP_GTP1U:
352 netdev_dbg(gtp->dev, "received GTP1U packet\n");
353 ret = gtp1u_udp_encap_recv(gtp, skb);
356 ret = -1; /* Shouldn't happen. */
361 netdev_dbg(gtp->dev, "pass up to the process\n");
366 netdev_dbg(gtp->dev, "GTP packet has been dropped\n");
375 static int gtp_dev_init(struct net_device *dev)
377 struct gtp_dev *gtp = netdev_priv(dev);
381 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
388 static void gtp_dev_uninit(struct net_device *dev)
390 struct gtp_dev *gtp = netdev_priv(dev);
392 gtp_encap_disable(gtp);
393 free_percpu(dev->tstats);
396 static struct rtable *ip4_route_output_gtp(struct flowi4 *fl4,
397 const struct sock *sk,
400 memset(fl4, 0, sizeof(*fl4));
401 fl4->flowi4_oif = sk->sk_bound_dev_if;
403 fl4->saddr = inet_sk(sk)->inet_saddr;
404 fl4->flowi4_tos = RT_CONN_FLAGS(sk);
405 fl4->flowi4_proto = sk->sk_protocol;
407 return ip_route_output_key(sock_net(sk), fl4);
410 static inline void gtp0_push_header(struct sk_buff *skb, struct pdp_ctx *pctx)
412 int payload_len = skb->len;
413 struct gtp0_header *gtp0;
415 gtp0 = skb_push(skb, sizeof(*gtp0));
417 gtp0->flags = 0x1e; /* v0, GTP-non-prime. */
418 gtp0->type = GTP_TPDU;
419 gtp0->length = htons(payload_len);
420 gtp0->seq = htons((atomic_inc_return(&pctx->tx_seq) - 1) % 0xffff);
421 gtp0->flow = htons(pctx->u.v0.flow);
423 gtp0->spare[0] = gtp0->spare[1] = gtp0->spare[2] = 0xff;
424 gtp0->tid = cpu_to_be64(pctx->u.v0.tid);
427 static inline void gtp1_push_header(struct sk_buff *skb, struct pdp_ctx *pctx)
429 int payload_len = skb->len;
430 struct gtp1_header *gtp1;
432 gtp1 = skb_push(skb, sizeof(*gtp1));
434 /* Bits 8 7 6 5 4 3 2 1
435 * +--+--+--+--+--+--+--+--+
436 * |version |PT| 0| E| S|PN|
437 * +--+--+--+--+--+--+--+--+
440 gtp1->flags = 0x30; /* v1, GTP-non-prime. */
441 gtp1->type = GTP_TPDU;
442 gtp1->length = htons(payload_len);
443 gtp1->tid = htonl(pctx->u.v1.o_tei);
445 /* TODO: Suppport for extension header, sequence number and N-PDU.
446 * Update the length field if any of them is available.
455 struct pdp_ctx *pctx;
456 struct net_device *dev;
460 static void gtp_push_header(struct sk_buff *skb, struct gtp_pktinfo *pktinfo)
462 switch (pktinfo->pctx->gtp_version) {
464 pktinfo->gtph_port = htons(GTP0_PORT);
465 gtp0_push_header(skb, pktinfo->pctx);
468 pktinfo->gtph_port = htons(GTP1U_PORT);
469 gtp1_push_header(skb, pktinfo->pctx);
474 static inline void gtp_set_pktinfo_ipv4(struct gtp_pktinfo *pktinfo,
475 struct sock *sk, struct iphdr *iph,
476 struct pdp_ctx *pctx, struct rtable *rt,
478 struct net_device *dev)
482 pktinfo->pctx = pctx;
488 static int gtp_build_skb_ip4(struct sk_buff *skb, struct net_device *dev,
489 struct gtp_pktinfo *pktinfo)
491 struct gtp_dev *gtp = netdev_priv(dev);
492 struct pdp_ctx *pctx;
499 /* Read the IP destination address and resolve the PDP context.
500 * Prepend PDP header with TEI/TID from PDP ctx.
503 if (gtp->role == GTP_ROLE_SGSN)
504 pctx = ipv4_pdp_find(gtp, iph->saddr);
506 pctx = ipv4_pdp_find(gtp, iph->daddr);
509 netdev_dbg(dev, "no PDP ctx found for %pI4, skip\n",
513 netdev_dbg(dev, "found PDP context %p\n", pctx);
515 rt = ip4_route_output_gtp(&fl4, pctx->sk, pctx->peer_addr_ip4.s_addr);
517 netdev_dbg(dev, "no route to SSGN %pI4\n",
518 &pctx->peer_addr_ip4.s_addr);
519 dev->stats.tx_carrier_errors++;
523 if (rt->dst.dev == dev) {
524 netdev_dbg(dev, "circular route to SSGN %pI4\n",
525 &pctx->peer_addr_ip4.s_addr);
526 dev->stats.collisions++;
532 /* This is similar to tnl_update_pmtu(). */
535 mtu = dst_mtu(&rt->dst) - dev->hard_header_len -
536 sizeof(struct iphdr) - sizeof(struct udphdr);
537 switch (pctx->gtp_version) {
539 mtu -= sizeof(struct gtp0_header);
542 mtu -= sizeof(struct gtp1_header);
546 mtu = dst_mtu(&rt->dst);
549 rt->dst.ops->update_pmtu(&rt->dst, NULL, skb, mtu, false);
551 if (!skb_is_gso(skb) && (iph->frag_off & htons(IP_DF)) &&
552 mtu < ntohs(iph->tot_len)) {
553 netdev_dbg(dev, "packet too big, fragmentation needed\n");
554 icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
559 gtp_set_pktinfo_ipv4(pktinfo, pctx->sk, iph, pctx, rt, &fl4, dev);
560 gtp_push_header(skb, pktinfo);
569 static netdev_tx_t gtp_dev_xmit(struct sk_buff *skb, struct net_device *dev)
571 unsigned int proto = ntohs(skb->protocol);
572 struct gtp_pktinfo pktinfo;
575 /* Ensure there is sufficient headroom. */
576 if (skb_cow_head(skb, dev->needed_headroom))
579 skb_reset_inner_headers(skb);
581 /* PDP context lookups in gtp_build_skb_*() need rcu read-side lock. */
585 err = gtp_build_skb_ip4(skb, dev, &pktinfo);
598 netdev_dbg(pktinfo.dev, "gtp -> IP src: %pI4 dst: %pI4\n",
599 &pktinfo.iph->saddr, &pktinfo.iph->daddr);
600 udp_tunnel_xmit_skb(pktinfo.rt, pktinfo.sk, skb,
601 pktinfo.fl4.saddr, pktinfo.fl4.daddr,
603 ip4_dst_hoplimit(&pktinfo.rt->dst),
605 pktinfo.gtph_port, pktinfo.gtph_port,
612 dev->stats.tx_errors++;
617 static const struct net_device_ops gtp_netdev_ops = {
618 .ndo_init = gtp_dev_init,
619 .ndo_uninit = gtp_dev_uninit,
620 .ndo_start_xmit = gtp_dev_xmit,
621 .ndo_get_stats64 = ip_tunnel_get_stats64,
624 static void gtp_link_setup(struct net_device *dev)
626 dev->netdev_ops = >p_netdev_ops;
627 dev->needs_free_netdev = true;
629 dev->hard_header_len = 0;
632 /* Zero header length. */
633 dev->type = ARPHRD_NONE;
634 dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
636 dev->priv_flags |= IFF_NO_QUEUE;
637 dev->features |= NETIF_F_LLTX;
640 /* Assume largest header, ie. GTPv0. */
641 dev->needed_headroom = LL_MAX_HEADER +
642 sizeof(struct iphdr) +
643 sizeof(struct udphdr) +
644 sizeof(struct gtp0_header);
647 static int gtp_hashtable_new(struct gtp_dev *gtp, int hsize);
648 static int gtp_encap_enable(struct gtp_dev *gtp, struct nlattr *data[]);
650 static void gtp_destructor(struct net_device *dev)
652 struct gtp_dev *gtp = netdev_priv(dev);
654 kfree(gtp->addr_hash);
655 kfree(gtp->tid_hash);
658 static int gtp_newlink(struct net *src_net, struct net_device *dev,
659 struct nlattr *tb[], struct nlattr *data[],
660 struct netlink_ext_ack *extack)
666 if (!data[IFLA_GTP_FD0] && !data[IFLA_GTP_FD1])
669 gtp = netdev_priv(dev);
671 if (!data[IFLA_GTP_PDP_HASHSIZE]) {
674 hashsize = nla_get_u32(data[IFLA_GTP_PDP_HASHSIZE]);
679 err = gtp_hashtable_new(gtp, hashsize);
683 err = gtp_encap_enable(gtp, data);
687 err = register_netdevice(dev);
689 netdev_dbg(dev, "failed to register new netdev %d\n", err);
693 gn = net_generic(dev_net(dev), gtp_net_id);
694 list_add_rcu(>p->list, &gn->gtp_dev_list);
695 dev->priv_destructor = gtp_destructor;
697 netdev_dbg(dev, "registered new GTP interface\n");
702 gtp_encap_disable(gtp);
704 kfree(gtp->addr_hash);
705 kfree(gtp->tid_hash);
709 static void gtp_dellink(struct net_device *dev, struct list_head *head)
711 struct gtp_dev *gtp = netdev_priv(dev);
712 struct pdp_ctx *pctx;
715 for (i = 0; i < gtp->hash_size; i++)
716 hlist_for_each_entry_rcu(pctx, >p->tid_hash[i], hlist_tid)
717 pdp_context_delete(pctx);
719 gtp_encap_disable(gtp);
720 list_del_rcu(>p->list);
721 unregister_netdevice_queue(dev, head);
724 static const struct nla_policy gtp_policy[IFLA_GTP_MAX + 1] = {
725 [IFLA_GTP_FD0] = { .type = NLA_U32 },
726 [IFLA_GTP_FD1] = { .type = NLA_U32 },
727 [IFLA_GTP_PDP_HASHSIZE] = { .type = NLA_U32 },
728 [IFLA_GTP_ROLE] = { .type = NLA_U32 },
731 static int gtp_validate(struct nlattr *tb[], struct nlattr *data[],
732 struct netlink_ext_ack *extack)
740 static size_t gtp_get_size(const struct net_device *dev)
742 return nla_total_size(sizeof(__u32)); /* IFLA_GTP_PDP_HASHSIZE */
745 static int gtp_fill_info(struct sk_buff *skb, const struct net_device *dev)
747 struct gtp_dev *gtp = netdev_priv(dev);
749 if (nla_put_u32(skb, IFLA_GTP_PDP_HASHSIZE, gtp->hash_size))
750 goto nla_put_failure;
758 static struct rtnl_link_ops gtp_link_ops __read_mostly = {
760 .maxtype = IFLA_GTP_MAX,
761 .policy = gtp_policy,
762 .priv_size = sizeof(struct gtp_dev),
763 .setup = gtp_link_setup,
764 .validate = gtp_validate,
765 .newlink = gtp_newlink,
766 .dellink = gtp_dellink,
767 .get_size = gtp_get_size,
768 .fill_info = gtp_fill_info,
771 static int gtp_hashtable_new(struct gtp_dev *gtp, int hsize)
775 gtp->addr_hash = kmalloc(sizeof(struct hlist_head) * hsize,
776 GFP_KERNEL | __GFP_NOWARN);
777 if (gtp->addr_hash == NULL)
780 gtp->tid_hash = kmalloc(sizeof(struct hlist_head) * hsize,
781 GFP_KERNEL | __GFP_NOWARN);
782 if (gtp->tid_hash == NULL)
785 gtp->hash_size = hsize;
787 for (i = 0; i < hsize; i++) {
788 INIT_HLIST_HEAD(>p->addr_hash[i]);
789 INIT_HLIST_HEAD(>p->tid_hash[i]);
793 kfree(gtp->addr_hash);
797 static struct sock *gtp_encap_enable_socket(int fd, int type,
800 struct udp_tunnel_sock_cfg tuncfg = {NULL};
805 pr_debug("enable gtp on %d, %d\n", fd, type);
807 sock = sockfd_lookup(fd, &err);
809 pr_debug("gtp socket fd=%d not found\n", fd);
814 if (sk->sk_protocol != IPPROTO_UDP ||
815 sk->sk_type != SOCK_DGRAM ||
816 (sk->sk_family != AF_INET && sk->sk_family != AF_INET6)) {
817 pr_debug("socket fd=%d not UDP\n", fd);
818 sk = ERR_PTR(-EINVAL);
823 if (sk->sk_user_data) {
824 sk = ERR_PTR(-EBUSY);
830 tuncfg.sk_user_data = gtp;
831 tuncfg.encap_type = type;
832 tuncfg.encap_rcv = gtp_encap_recv;
833 tuncfg.encap_destroy = gtp_encap_destroy;
835 setup_udp_tunnel_sock(sock_net(sock->sk), sock, &tuncfg);
838 release_sock(sock->sk);
844 static int gtp_encap_enable(struct gtp_dev *gtp, struct nlattr *data[])
846 struct sock *sk1u = NULL;
847 struct sock *sk0 = NULL;
848 unsigned int role = GTP_ROLE_GGSN;
850 if (data[IFLA_GTP_FD0]) {
851 u32 fd0 = nla_get_u32(data[IFLA_GTP_FD0]);
853 sk0 = gtp_encap_enable_socket(fd0, UDP_ENCAP_GTP0, gtp);
858 if (data[IFLA_GTP_FD1]) {
859 u32 fd1 = nla_get_u32(data[IFLA_GTP_FD1]);
861 sk1u = gtp_encap_enable_socket(fd1, UDP_ENCAP_GTP1U, gtp);
864 gtp_encap_disable_sock(sk0);
865 return PTR_ERR(sk1u);
869 if (data[IFLA_GTP_ROLE]) {
870 role = nla_get_u32(data[IFLA_GTP_ROLE]);
871 if (role > GTP_ROLE_SGSN) {
873 gtp_encap_disable_sock(sk0);
875 gtp_encap_disable_sock(sk1u);
887 static struct gtp_dev *gtp_find_dev(struct net *src_net, struct nlattr *nla[])
889 struct gtp_dev *gtp = NULL;
890 struct net_device *dev;
893 /* Examine the link attributes and figure out which network namespace
894 * we are talking about.
896 if (nla[GTPA_NET_NS_FD])
897 net = get_net_ns_by_fd(nla_get_u32(nla[GTPA_NET_NS_FD]));
899 net = get_net(src_net);
904 /* Check if there's an existing gtpX device to configure */
905 dev = dev_get_by_index_rcu(net, nla_get_u32(nla[GTPA_LINK]));
906 if (dev && dev->netdev_ops == >p_netdev_ops)
907 gtp = netdev_priv(dev);
913 static void ipv4_pdp_fill(struct pdp_ctx *pctx, struct genl_info *info)
915 pctx->gtp_version = nla_get_u32(info->attrs[GTPA_VERSION]);
917 pctx->peer_addr_ip4.s_addr =
918 nla_get_be32(info->attrs[GTPA_PEER_ADDRESS]);
919 pctx->ms_addr_ip4.s_addr =
920 nla_get_be32(info->attrs[GTPA_MS_ADDRESS]);
922 switch (pctx->gtp_version) {
924 /* According to TS 09.60, sections 7.5.1 and 7.5.2, the flow
925 * label needs to be the same for uplink and downlink packets,
926 * so let's annotate this.
928 pctx->u.v0.tid = nla_get_u64(info->attrs[GTPA_TID]);
929 pctx->u.v0.flow = nla_get_u16(info->attrs[GTPA_FLOW]);
932 pctx->u.v1.i_tei = nla_get_u32(info->attrs[GTPA_I_TEI]);
933 pctx->u.v1.o_tei = nla_get_u32(info->attrs[GTPA_O_TEI]);
940 static int gtp_pdp_add(struct gtp_dev *gtp, struct sock *sk,
941 struct genl_info *info)
943 struct pdp_ctx *pctx, *pctx_tid = NULL;
944 struct net_device *dev = gtp->dev;
945 u32 hash_ms, hash_tid = 0;
946 unsigned int version;
950 ms_addr = nla_get_be32(info->attrs[GTPA_MS_ADDRESS]);
951 hash_ms = ipv4_hashfn(ms_addr) % gtp->hash_size;
952 version = nla_get_u32(info->attrs[GTPA_VERSION]);
954 pctx = ipv4_pdp_find(gtp, ms_addr);
957 if (version == GTP_V0)
958 pctx_tid = gtp0_pdp_find(gtp,
959 nla_get_u64(info->attrs[GTPA_TID]));
960 else if (version == GTP_V1)
961 pctx_tid = gtp1_pdp_find(gtp,
962 nla_get_u32(info->attrs[GTPA_I_TEI]));
967 if (info->nlhdr->nlmsg_flags & NLM_F_EXCL)
969 if (info->nlhdr->nlmsg_flags & NLM_F_REPLACE)
972 if (pctx && pctx_tid)
977 ipv4_pdp_fill(pctx, info);
979 if (pctx->gtp_version == GTP_V0)
980 netdev_dbg(dev, "GTPv0-U: update tunnel id = %llx (pdp %p)\n",
981 pctx->u.v0.tid, pctx);
982 else if (pctx->gtp_version == GTP_V1)
983 netdev_dbg(dev, "GTPv1-U: update tunnel id = %x/%x (pdp %p)\n",
984 pctx->u.v1.i_tei, pctx->u.v1.o_tei, pctx);
990 pctx = kmalloc(sizeof(*pctx), GFP_ATOMIC);
996 pctx->dev = gtp->dev;
997 ipv4_pdp_fill(pctx, info);
998 atomic_set(&pctx->tx_seq, 0);
1000 switch (pctx->gtp_version) {
1002 /* TS 09.60: "The flow label identifies unambiguously a GTP
1003 * flow.". We use the tid for this instead, I cannot find a
1004 * situation in which this doesn't unambiguosly identify the
1007 hash_tid = gtp0_hashfn(pctx->u.v0.tid) % gtp->hash_size;
1010 hash_tid = gtp1u_hashfn(pctx->u.v1.i_tei) % gtp->hash_size;
1014 hlist_add_head_rcu(&pctx->hlist_addr, >p->addr_hash[hash_ms]);
1015 hlist_add_head_rcu(&pctx->hlist_tid, >p->tid_hash[hash_tid]);
1017 switch (pctx->gtp_version) {
1019 netdev_dbg(dev, "GTPv0-U: new PDP ctx id=%llx ssgn=%pI4 ms=%pI4 (pdp=%p)\n",
1020 pctx->u.v0.tid, &pctx->peer_addr_ip4,
1021 &pctx->ms_addr_ip4, pctx);
1024 netdev_dbg(dev, "GTPv1-U: new PDP ctx id=%x/%x ssgn=%pI4 ms=%pI4 (pdp=%p)\n",
1025 pctx->u.v1.i_tei, pctx->u.v1.o_tei,
1026 &pctx->peer_addr_ip4, &pctx->ms_addr_ip4, pctx);
1033 static void pdp_context_free(struct rcu_head *head)
1035 struct pdp_ctx *pctx = container_of(head, struct pdp_ctx, rcu_head);
1041 static void pdp_context_delete(struct pdp_ctx *pctx)
1043 hlist_del_rcu(&pctx->hlist_tid);
1044 hlist_del_rcu(&pctx->hlist_addr);
1045 call_rcu(&pctx->rcu_head, pdp_context_free);
1048 static int gtp_genl_new_pdp(struct sk_buff *skb, struct genl_info *info)
1050 unsigned int version;
1051 struct gtp_dev *gtp;
1055 if (!info->attrs[GTPA_VERSION] ||
1056 !info->attrs[GTPA_LINK] ||
1057 !info->attrs[GTPA_PEER_ADDRESS] ||
1058 !info->attrs[GTPA_MS_ADDRESS])
1061 version = nla_get_u32(info->attrs[GTPA_VERSION]);
1065 if (!info->attrs[GTPA_TID] ||
1066 !info->attrs[GTPA_FLOW])
1070 if (!info->attrs[GTPA_I_TEI] ||
1071 !info->attrs[GTPA_O_TEI])
1082 gtp = gtp_find_dev(sock_net(skb->sk), info->attrs);
1088 if (version == GTP_V0)
1090 else if (version == GTP_V1)
1100 err = gtp_pdp_add(gtp, sk, info);
1108 static struct pdp_ctx *gtp_find_pdp_by_link(struct net *net,
1109 struct nlattr *nla[])
1111 struct gtp_dev *gtp;
1113 gtp = gtp_find_dev(net, nla);
1115 return ERR_PTR(-ENODEV);
1117 if (nla[GTPA_MS_ADDRESS]) {
1118 __be32 ip = nla_get_be32(nla[GTPA_MS_ADDRESS]);
1120 return ipv4_pdp_find(gtp, ip);
1121 } else if (nla[GTPA_VERSION]) {
1122 u32 gtp_version = nla_get_u32(nla[GTPA_VERSION]);
1124 if (gtp_version == GTP_V0 && nla[GTPA_TID])
1125 return gtp0_pdp_find(gtp, nla_get_u64(nla[GTPA_TID]));
1126 else if (gtp_version == GTP_V1 && nla[GTPA_I_TEI])
1127 return gtp1_pdp_find(gtp, nla_get_u32(nla[GTPA_I_TEI]));
1130 return ERR_PTR(-EINVAL);
1133 static struct pdp_ctx *gtp_find_pdp(struct net *net, struct nlattr *nla[])
1135 struct pdp_ctx *pctx;
1138 pctx = gtp_find_pdp_by_link(net, nla);
1140 pctx = ERR_PTR(-EINVAL);
1143 pctx = ERR_PTR(-ENOENT);
1148 static int gtp_genl_del_pdp(struct sk_buff *skb, struct genl_info *info)
1150 struct pdp_ctx *pctx;
1153 if (!info->attrs[GTPA_VERSION])
1158 pctx = gtp_find_pdp(sock_net(skb->sk), info->attrs);
1160 err = PTR_ERR(pctx);
1164 if (pctx->gtp_version == GTP_V0)
1165 netdev_dbg(pctx->dev, "GTPv0-U: deleting tunnel id = %llx (pdp %p)\n",
1166 pctx->u.v0.tid, pctx);
1167 else if (pctx->gtp_version == GTP_V1)
1168 netdev_dbg(pctx->dev, "GTPv1-U: deleting tunnel id = %x/%x (pdp %p)\n",
1169 pctx->u.v1.i_tei, pctx->u.v1.o_tei, pctx);
1171 pdp_context_delete(pctx);
1178 static struct genl_family gtp_genl_family;
1180 static int gtp_genl_fill_info(struct sk_buff *skb, u32 snd_portid, u32 snd_seq,
1181 int flags, u32 type, struct pdp_ctx *pctx)
1185 genlh = genlmsg_put(skb, snd_portid, snd_seq, >p_genl_family, flags,
1190 if (nla_put_u32(skb, GTPA_VERSION, pctx->gtp_version) ||
1191 nla_put_u32(skb, GTPA_LINK, pctx->dev->ifindex) ||
1192 nla_put_be32(skb, GTPA_PEER_ADDRESS, pctx->peer_addr_ip4.s_addr) ||
1193 nla_put_be32(skb, GTPA_MS_ADDRESS, pctx->ms_addr_ip4.s_addr))
1194 goto nla_put_failure;
1196 switch (pctx->gtp_version) {
1198 if (nla_put_u64_64bit(skb, GTPA_TID, pctx->u.v0.tid, GTPA_PAD) ||
1199 nla_put_u16(skb, GTPA_FLOW, pctx->u.v0.flow))
1200 goto nla_put_failure;
1203 if (nla_put_u32(skb, GTPA_I_TEI, pctx->u.v1.i_tei) ||
1204 nla_put_u32(skb, GTPA_O_TEI, pctx->u.v1.o_tei))
1205 goto nla_put_failure;
1208 genlmsg_end(skb, genlh);
1213 genlmsg_cancel(skb, genlh);
1217 static int gtp_genl_get_pdp(struct sk_buff *skb, struct genl_info *info)
1219 struct pdp_ctx *pctx = NULL;
1220 struct sk_buff *skb2;
1223 if (!info->attrs[GTPA_VERSION])
1228 pctx = gtp_find_pdp(sock_net(skb->sk), info->attrs);
1230 err = PTR_ERR(pctx);
1234 skb2 = genlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC);
1240 err = gtp_genl_fill_info(skb2, NETLINK_CB(skb).portid, info->snd_seq,
1241 0, info->nlhdr->nlmsg_type, pctx);
1243 goto err_unlock_free;
1246 return genlmsg_unicast(genl_info_net(info), skb2, info->snd_portid);
1255 static int gtp_genl_dump_pdp(struct sk_buff *skb,
1256 struct netlink_callback *cb)
1258 struct gtp_dev *last_gtp = (struct gtp_dev *)cb->args[2], *gtp;
1259 int i, j, bucket = cb->args[0], skip = cb->args[1];
1260 struct net *net = sock_net(skb->sk);
1261 struct pdp_ctx *pctx;
1264 gn = net_generic(net, gtp_net_id);
1270 list_for_each_entry_rcu(gtp, &gn->gtp_dev_list, list) {
1271 if (last_gtp && last_gtp != gtp)
1276 for (i = bucket; i < gtp->hash_size; i++) {
1278 hlist_for_each_entry_rcu(pctx, >p->tid_hash[i],
1281 gtp_genl_fill_info(skb,
1282 NETLINK_CB(cb->skb).portid,
1285 cb->nlh->nlmsg_type, pctx)) {
1288 cb->args[2] = (unsigned long)gtp;
1303 static struct nla_policy gtp_genl_policy[GTPA_MAX + 1] = {
1304 [GTPA_LINK] = { .type = NLA_U32, },
1305 [GTPA_VERSION] = { .type = NLA_U32, },
1306 [GTPA_TID] = { .type = NLA_U64, },
1307 [GTPA_PEER_ADDRESS] = { .type = NLA_U32, },
1308 [GTPA_MS_ADDRESS] = { .type = NLA_U32, },
1309 [GTPA_FLOW] = { .type = NLA_U16, },
1310 [GTPA_NET_NS_FD] = { .type = NLA_U32, },
1311 [GTPA_I_TEI] = { .type = NLA_U32, },
1312 [GTPA_O_TEI] = { .type = NLA_U32, },
1315 static const struct genl_ops gtp_genl_ops[] = {
1317 .cmd = GTP_CMD_NEWPDP,
1318 .doit = gtp_genl_new_pdp,
1319 .policy = gtp_genl_policy,
1320 .flags = GENL_ADMIN_PERM,
1323 .cmd = GTP_CMD_DELPDP,
1324 .doit = gtp_genl_del_pdp,
1325 .policy = gtp_genl_policy,
1326 .flags = GENL_ADMIN_PERM,
1329 .cmd = GTP_CMD_GETPDP,
1330 .doit = gtp_genl_get_pdp,
1331 .dumpit = gtp_genl_dump_pdp,
1332 .policy = gtp_genl_policy,
1333 .flags = GENL_ADMIN_PERM,
1337 static struct genl_family gtp_genl_family __ro_after_init = {
1341 .maxattr = GTPA_MAX,
1343 .module = THIS_MODULE,
1344 .ops = gtp_genl_ops,
1345 .n_ops = ARRAY_SIZE(gtp_genl_ops),
1348 static int __net_init gtp_net_init(struct net *net)
1350 struct gtp_net *gn = net_generic(net, gtp_net_id);
1352 INIT_LIST_HEAD(&gn->gtp_dev_list);
1356 static void __net_exit gtp_net_exit(struct net *net)
1358 struct gtp_net *gn = net_generic(net, gtp_net_id);
1359 struct gtp_dev *gtp;
1363 list_for_each_entry(gtp, &gn->gtp_dev_list, list)
1364 gtp_dellink(gtp->dev, &list);
1366 unregister_netdevice_many(&list);
1370 static struct pernet_operations gtp_net_ops = {
1371 .init = gtp_net_init,
1372 .exit = gtp_net_exit,
1374 .size = sizeof(struct gtp_net),
1377 static int __init gtp_init(void)
1381 get_random_bytes(>p_h_initval, sizeof(gtp_h_initval));
1383 err = rtnl_link_register(>p_link_ops);
1387 err = genl_register_family(>p_genl_family);
1389 goto unreg_rtnl_link;
1391 err = register_pernet_subsys(>p_net_ops);
1393 goto unreg_genl_family;
1395 pr_info("GTP module loaded (pdp ctx size %zd bytes)\n",
1396 sizeof(struct pdp_ctx));
1400 genl_unregister_family(>p_genl_family);
1402 rtnl_link_unregister(>p_link_ops);
1404 pr_err("error loading GTP module loaded\n");
1407 late_initcall(gtp_init);
1409 static void __exit gtp_fini(void)
1411 genl_unregister_family(>p_genl_family);
1412 rtnl_link_unregister(>p_link_ops);
1413 unregister_pernet_subsys(>p_net_ops);
1415 pr_info("GTP module unloaded\n");
1417 module_exit(gtp_fini);
1419 MODULE_LICENSE("GPL");
1420 MODULE_AUTHOR("Harald Welte <hwelte@sysmocom.de>");
1421 MODULE_DESCRIPTION("Interface driver for GTP encapsulated traffic");
1422 MODULE_ALIAS_RTNL_LINK("gtp");
1423 MODULE_ALIAS_GENL_FAMILY("gtp");