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);
309 static void gtp_encap_destroy(struct sock *sk)
312 __gtp_encap_destroy(sk);
316 static void gtp_encap_disable_sock(struct sock *sk)
321 __gtp_encap_destroy(sk);
324 static void gtp_encap_disable(struct gtp_dev *gtp)
326 gtp_encap_disable_sock(gtp->sk0);
327 gtp_encap_disable_sock(gtp->sk1u);
330 /* UDP encapsulation receive handler. See net/ipv4/udp.c.
331 * Return codes: 0: success, <0: error, >0: pass up to userspace UDP socket.
333 static int gtp_encap_recv(struct sock *sk, struct sk_buff *skb)
338 gtp = rcu_dereference_sk_user_data(sk);
342 netdev_dbg(gtp->dev, "encap_recv sk=%p\n", sk);
344 switch (udp_sk(sk)->encap_type) {
346 netdev_dbg(gtp->dev, "received GTP0 packet\n");
347 ret = gtp0_udp_encap_recv(gtp, skb);
349 case UDP_ENCAP_GTP1U:
350 netdev_dbg(gtp->dev, "received GTP1U packet\n");
351 ret = gtp1u_udp_encap_recv(gtp, skb);
354 ret = -1; /* Shouldn't happen. */
359 netdev_dbg(gtp->dev, "pass up to the process\n");
364 netdev_dbg(gtp->dev, "GTP packet has been dropped\n");
373 static int gtp_dev_init(struct net_device *dev)
375 struct gtp_dev *gtp = netdev_priv(dev);
379 dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
386 static void gtp_dev_uninit(struct net_device *dev)
388 struct gtp_dev *gtp = netdev_priv(dev);
390 gtp_encap_disable(gtp);
391 free_percpu(dev->tstats);
394 static struct rtable *ip4_route_output_gtp(struct flowi4 *fl4,
395 const struct sock *sk,
398 memset(fl4, 0, sizeof(*fl4));
399 fl4->flowi4_oif = sk->sk_bound_dev_if;
401 fl4->saddr = inet_sk(sk)->inet_saddr;
402 fl4->flowi4_tos = RT_CONN_FLAGS(sk);
403 fl4->flowi4_proto = sk->sk_protocol;
405 return ip_route_output_key(sock_net(sk), fl4);
408 static inline void gtp0_push_header(struct sk_buff *skb, struct pdp_ctx *pctx)
410 int payload_len = skb->len;
411 struct gtp0_header *gtp0;
413 gtp0 = skb_push(skb, sizeof(*gtp0));
415 gtp0->flags = 0x1e; /* v0, GTP-non-prime. */
416 gtp0->type = GTP_TPDU;
417 gtp0->length = htons(payload_len);
418 gtp0->seq = htons((atomic_inc_return(&pctx->tx_seq) - 1) % 0xffff);
419 gtp0->flow = htons(pctx->u.v0.flow);
421 gtp0->spare[0] = gtp0->spare[1] = gtp0->spare[2] = 0xff;
422 gtp0->tid = cpu_to_be64(pctx->u.v0.tid);
425 static inline void gtp1_push_header(struct sk_buff *skb, struct pdp_ctx *pctx)
427 int payload_len = skb->len;
428 struct gtp1_header *gtp1;
430 gtp1 = skb_push(skb, sizeof(*gtp1));
432 /* Bits 8 7 6 5 4 3 2 1
433 * +--+--+--+--+--+--+--+--+
434 * |version |PT| 0| E| S|PN|
435 * +--+--+--+--+--+--+--+--+
438 gtp1->flags = 0x30; /* v1, GTP-non-prime. */
439 gtp1->type = GTP_TPDU;
440 gtp1->length = htons(payload_len);
441 gtp1->tid = htonl(pctx->u.v1.o_tei);
443 /* TODO: Suppport for extension header, sequence number and N-PDU.
444 * Update the length field if any of them is available.
453 struct pdp_ctx *pctx;
454 struct net_device *dev;
458 static void gtp_push_header(struct sk_buff *skb, struct gtp_pktinfo *pktinfo)
460 switch (pktinfo->pctx->gtp_version) {
462 pktinfo->gtph_port = htons(GTP0_PORT);
463 gtp0_push_header(skb, pktinfo->pctx);
466 pktinfo->gtph_port = htons(GTP1U_PORT);
467 gtp1_push_header(skb, pktinfo->pctx);
472 static inline void gtp_set_pktinfo_ipv4(struct gtp_pktinfo *pktinfo,
473 struct sock *sk, struct iphdr *iph,
474 struct pdp_ctx *pctx, struct rtable *rt,
476 struct net_device *dev)
480 pktinfo->pctx = pctx;
486 static int gtp_build_skb_ip4(struct sk_buff *skb, struct net_device *dev,
487 struct gtp_pktinfo *pktinfo)
489 struct gtp_dev *gtp = netdev_priv(dev);
490 struct pdp_ctx *pctx;
497 /* Read the IP destination address and resolve the PDP context.
498 * Prepend PDP header with TEI/TID from PDP ctx.
501 if (gtp->role == GTP_ROLE_SGSN)
502 pctx = ipv4_pdp_find(gtp, iph->saddr);
504 pctx = ipv4_pdp_find(gtp, iph->daddr);
507 netdev_dbg(dev, "no PDP ctx found for %pI4, skip\n",
511 netdev_dbg(dev, "found PDP context %p\n", pctx);
513 rt = ip4_route_output_gtp(&fl4, pctx->sk, pctx->peer_addr_ip4.s_addr);
515 netdev_dbg(dev, "no route to SSGN %pI4\n",
516 &pctx->peer_addr_ip4.s_addr);
517 dev->stats.tx_carrier_errors++;
521 if (rt->dst.dev == dev) {
522 netdev_dbg(dev, "circular route to SSGN %pI4\n",
523 &pctx->peer_addr_ip4.s_addr);
524 dev->stats.collisions++;
530 /* This is similar to tnl_update_pmtu(). */
533 mtu = dst_mtu(&rt->dst) - dev->hard_header_len -
534 sizeof(struct iphdr) - sizeof(struct udphdr);
535 switch (pctx->gtp_version) {
537 mtu -= sizeof(struct gtp0_header);
540 mtu -= sizeof(struct gtp1_header);
544 mtu = dst_mtu(&rt->dst);
547 rt->dst.ops->update_pmtu(&rt->dst, NULL, skb, mtu, false);
549 if (!skb_is_gso(skb) && (iph->frag_off & htons(IP_DF)) &&
550 mtu < ntohs(iph->tot_len)) {
551 netdev_dbg(dev, "packet too big, fragmentation needed\n");
552 icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
557 gtp_set_pktinfo_ipv4(pktinfo, pctx->sk, iph, pctx, rt, &fl4, dev);
558 gtp_push_header(skb, pktinfo);
567 static netdev_tx_t gtp_dev_xmit(struct sk_buff *skb, struct net_device *dev)
569 unsigned int proto = ntohs(skb->protocol);
570 struct gtp_pktinfo pktinfo;
573 /* Ensure there is sufficient headroom. */
574 if (skb_cow_head(skb, dev->needed_headroom))
577 skb_reset_inner_headers(skb);
579 /* PDP context lookups in gtp_build_skb_*() need rcu read-side lock. */
583 err = gtp_build_skb_ip4(skb, dev, &pktinfo);
596 netdev_dbg(pktinfo.dev, "gtp -> IP src: %pI4 dst: %pI4\n",
597 &pktinfo.iph->saddr, &pktinfo.iph->daddr);
598 udp_tunnel_xmit_skb(pktinfo.rt, pktinfo.sk, skb,
599 pktinfo.fl4.saddr, pktinfo.fl4.daddr,
601 ip4_dst_hoplimit(&pktinfo.rt->dst),
603 pktinfo.gtph_port, pktinfo.gtph_port,
610 dev->stats.tx_errors++;
615 static const struct net_device_ops gtp_netdev_ops = {
616 .ndo_init = gtp_dev_init,
617 .ndo_uninit = gtp_dev_uninit,
618 .ndo_start_xmit = gtp_dev_xmit,
619 .ndo_get_stats64 = ip_tunnel_get_stats64,
622 static void gtp_link_setup(struct net_device *dev)
624 dev->netdev_ops = >p_netdev_ops;
625 dev->needs_free_netdev = true;
627 dev->hard_header_len = 0;
630 /* Zero header length. */
631 dev->type = ARPHRD_NONE;
632 dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
634 dev->priv_flags |= IFF_NO_QUEUE;
635 dev->features |= NETIF_F_LLTX;
638 /* Assume largest header, ie. GTPv0. */
639 dev->needed_headroom = LL_MAX_HEADER +
640 sizeof(struct iphdr) +
641 sizeof(struct udphdr) +
642 sizeof(struct gtp0_header);
645 static int gtp_hashtable_new(struct gtp_dev *gtp, int hsize);
646 static int gtp_encap_enable(struct gtp_dev *gtp, struct nlattr *data[]);
648 static void gtp_destructor(struct net_device *dev)
650 struct gtp_dev *gtp = netdev_priv(dev);
652 kfree(gtp->addr_hash);
653 kfree(gtp->tid_hash);
656 static int gtp_newlink(struct net *src_net, struct net_device *dev,
657 struct nlattr *tb[], struct nlattr *data[],
658 struct netlink_ext_ack *extack)
664 if (!data[IFLA_GTP_FD0] && !data[IFLA_GTP_FD1])
667 gtp = netdev_priv(dev);
669 if (!data[IFLA_GTP_PDP_HASHSIZE]) {
672 hashsize = nla_get_u32(data[IFLA_GTP_PDP_HASHSIZE]);
677 err = gtp_hashtable_new(gtp, hashsize);
681 err = gtp_encap_enable(gtp, data);
685 err = register_netdevice(dev);
687 netdev_dbg(dev, "failed to register new netdev %d\n", err);
691 gn = net_generic(dev_net(dev), gtp_net_id);
692 list_add_rcu(>p->list, &gn->gtp_dev_list);
693 dev->priv_destructor = gtp_destructor;
695 netdev_dbg(dev, "registered new GTP interface\n");
700 gtp_encap_disable(gtp);
702 kfree(gtp->addr_hash);
703 kfree(gtp->tid_hash);
707 static void gtp_dellink(struct net_device *dev, struct list_head *head)
709 struct gtp_dev *gtp = netdev_priv(dev);
710 struct pdp_ctx *pctx;
713 for (i = 0; i < gtp->hash_size; i++)
714 hlist_for_each_entry_rcu(pctx, >p->tid_hash[i], hlist_tid)
715 pdp_context_delete(pctx);
717 gtp_encap_disable(gtp);
718 list_del_rcu(>p->list);
719 unregister_netdevice_queue(dev, head);
722 static const struct nla_policy gtp_policy[IFLA_GTP_MAX + 1] = {
723 [IFLA_GTP_FD0] = { .type = NLA_U32 },
724 [IFLA_GTP_FD1] = { .type = NLA_U32 },
725 [IFLA_GTP_PDP_HASHSIZE] = { .type = NLA_U32 },
726 [IFLA_GTP_ROLE] = { .type = NLA_U32 },
729 static int gtp_validate(struct nlattr *tb[], struct nlattr *data[],
730 struct netlink_ext_ack *extack)
738 static size_t gtp_get_size(const struct net_device *dev)
740 return nla_total_size(sizeof(__u32)); /* IFLA_GTP_PDP_HASHSIZE */
743 static int gtp_fill_info(struct sk_buff *skb, const struct net_device *dev)
745 struct gtp_dev *gtp = netdev_priv(dev);
747 if (nla_put_u32(skb, IFLA_GTP_PDP_HASHSIZE, gtp->hash_size))
748 goto nla_put_failure;
756 static struct rtnl_link_ops gtp_link_ops __read_mostly = {
758 .maxtype = IFLA_GTP_MAX,
759 .policy = gtp_policy,
760 .priv_size = sizeof(struct gtp_dev),
761 .setup = gtp_link_setup,
762 .validate = gtp_validate,
763 .newlink = gtp_newlink,
764 .dellink = gtp_dellink,
765 .get_size = gtp_get_size,
766 .fill_info = gtp_fill_info,
769 static int gtp_hashtable_new(struct gtp_dev *gtp, int hsize)
773 gtp->addr_hash = kmalloc_array(hsize, sizeof(struct hlist_head),
774 GFP_KERNEL | __GFP_NOWARN);
775 if (gtp->addr_hash == NULL)
778 gtp->tid_hash = kmalloc_array(hsize, sizeof(struct hlist_head),
779 GFP_KERNEL | __GFP_NOWARN);
780 if (gtp->tid_hash == NULL)
783 gtp->hash_size = hsize;
785 for (i = 0; i < hsize; i++) {
786 INIT_HLIST_HEAD(>p->addr_hash[i]);
787 INIT_HLIST_HEAD(>p->tid_hash[i]);
791 kfree(gtp->addr_hash);
795 static struct sock *gtp_encap_enable_socket(int fd, int type,
798 struct udp_tunnel_sock_cfg tuncfg = {NULL};
803 pr_debug("enable gtp on %d, %d\n", fd, type);
805 sock = sockfd_lookup(fd, &err);
807 pr_debug("gtp socket fd=%d not found\n", fd);
812 if (sk->sk_protocol != IPPROTO_UDP ||
813 sk->sk_type != SOCK_DGRAM ||
814 (sk->sk_family != AF_INET && sk->sk_family != AF_INET6)) {
815 pr_debug("socket fd=%d not UDP\n", fd);
816 sk = ERR_PTR(-EINVAL);
821 if (sk->sk_user_data) {
822 sk = ERR_PTR(-EBUSY);
828 tuncfg.sk_user_data = gtp;
829 tuncfg.encap_type = type;
830 tuncfg.encap_rcv = gtp_encap_recv;
831 tuncfg.encap_destroy = gtp_encap_destroy;
833 setup_udp_tunnel_sock(sock_net(sock->sk), sock, &tuncfg);
836 release_sock(sock->sk);
842 static int gtp_encap_enable(struct gtp_dev *gtp, struct nlattr *data[])
844 struct sock *sk1u = NULL;
845 struct sock *sk0 = NULL;
846 unsigned int role = GTP_ROLE_GGSN;
848 if (data[IFLA_GTP_FD0]) {
849 u32 fd0 = nla_get_u32(data[IFLA_GTP_FD0]);
851 sk0 = gtp_encap_enable_socket(fd0, UDP_ENCAP_GTP0, gtp);
856 if (data[IFLA_GTP_FD1]) {
857 u32 fd1 = nla_get_u32(data[IFLA_GTP_FD1]);
859 sk1u = gtp_encap_enable_socket(fd1, UDP_ENCAP_GTP1U, gtp);
862 gtp_encap_disable_sock(sk0);
863 return PTR_ERR(sk1u);
867 if (data[IFLA_GTP_ROLE]) {
868 role = nla_get_u32(data[IFLA_GTP_ROLE]);
869 if (role > GTP_ROLE_SGSN) {
871 gtp_encap_disable_sock(sk0);
873 gtp_encap_disable_sock(sk1u);
885 static struct gtp_dev *gtp_find_dev(struct net *src_net, struct nlattr *nla[])
887 struct gtp_dev *gtp = NULL;
888 struct net_device *dev;
891 /* Examine the link attributes and figure out which network namespace
892 * we are talking about.
894 if (nla[GTPA_NET_NS_FD])
895 net = get_net_ns_by_fd(nla_get_u32(nla[GTPA_NET_NS_FD]));
897 net = get_net(src_net);
902 /* Check if there's an existing gtpX device to configure */
903 dev = dev_get_by_index_rcu(net, nla_get_u32(nla[GTPA_LINK]));
904 if (dev && dev->netdev_ops == >p_netdev_ops)
905 gtp = netdev_priv(dev);
911 static void ipv4_pdp_fill(struct pdp_ctx *pctx, struct genl_info *info)
913 pctx->gtp_version = nla_get_u32(info->attrs[GTPA_VERSION]);
915 pctx->peer_addr_ip4.s_addr =
916 nla_get_be32(info->attrs[GTPA_PEER_ADDRESS]);
917 pctx->ms_addr_ip4.s_addr =
918 nla_get_be32(info->attrs[GTPA_MS_ADDRESS]);
920 switch (pctx->gtp_version) {
922 /* According to TS 09.60, sections 7.5.1 and 7.5.2, the flow
923 * label needs to be the same for uplink and downlink packets,
924 * so let's annotate this.
926 pctx->u.v0.tid = nla_get_u64(info->attrs[GTPA_TID]);
927 pctx->u.v0.flow = nla_get_u16(info->attrs[GTPA_FLOW]);
930 pctx->u.v1.i_tei = nla_get_u32(info->attrs[GTPA_I_TEI]);
931 pctx->u.v1.o_tei = nla_get_u32(info->attrs[GTPA_O_TEI]);
938 static int gtp_pdp_add(struct gtp_dev *gtp, struct sock *sk,
939 struct genl_info *info)
941 struct pdp_ctx *pctx, *pctx_tid = NULL;
942 struct net_device *dev = gtp->dev;
943 u32 hash_ms, hash_tid = 0;
944 unsigned int version;
948 ms_addr = nla_get_be32(info->attrs[GTPA_MS_ADDRESS]);
949 hash_ms = ipv4_hashfn(ms_addr) % gtp->hash_size;
950 version = nla_get_u32(info->attrs[GTPA_VERSION]);
952 pctx = ipv4_pdp_find(gtp, ms_addr);
955 if (version == GTP_V0)
956 pctx_tid = gtp0_pdp_find(gtp,
957 nla_get_u64(info->attrs[GTPA_TID]));
958 else if (version == GTP_V1)
959 pctx_tid = gtp1_pdp_find(gtp,
960 nla_get_u32(info->attrs[GTPA_I_TEI]));
965 if (info->nlhdr->nlmsg_flags & NLM_F_EXCL)
967 if (info->nlhdr->nlmsg_flags & NLM_F_REPLACE)
970 if (pctx && pctx_tid)
975 ipv4_pdp_fill(pctx, info);
977 if (pctx->gtp_version == GTP_V0)
978 netdev_dbg(dev, "GTPv0-U: update tunnel id = %llx (pdp %p)\n",
979 pctx->u.v0.tid, pctx);
980 else if (pctx->gtp_version == GTP_V1)
981 netdev_dbg(dev, "GTPv1-U: update tunnel id = %x/%x (pdp %p)\n",
982 pctx->u.v1.i_tei, pctx->u.v1.o_tei, pctx);
988 pctx = kmalloc(sizeof(*pctx), GFP_ATOMIC);
994 pctx->dev = gtp->dev;
995 ipv4_pdp_fill(pctx, info);
996 atomic_set(&pctx->tx_seq, 0);
998 switch (pctx->gtp_version) {
1000 /* TS 09.60: "The flow label identifies unambiguously a GTP
1001 * flow.". We use the tid for this instead, I cannot find a
1002 * situation in which this doesn't unambiguosly identify the
1005 hash_tid = gtp0_hashfn(pctx->u.v0.tid) % gtp->hash_size;
1008 hash_tid = gtp1u_hashfn(pctx->u.v1.i_tei) % gtp->hash_size;
1012 hlist_add_head_rcu(&pctx->hlist_addr, >p->addr_hash[hash_ms]);
1013 hlist_add_head_rcu(&pctx->hlist_tid, >p->tid_hash[hash_tid]);
1015 switch (pctx->gtp_version) {
1017 netdev_dbg(dev, "GTPv0-U: new PDP ctx id=%llx ssgn=%pI4 ms=%pI4 (pdp=%p)\n",
1018 pctx->u.v0.tid, &pctx->peer_addr_ip4,
1019 &pctx->ms_addr_ip4, pctx);
1022 netdev_dbg(dev, "GTPv1-U: new PDP ctx id=%x/%x ssgn=%pI4 ms=%pI4 (pdp=%p)\n",
1023 pctx->u.v1.i_tei, pctx->u.v1.o_tei,
1024 &pctx->peer_addr_ip4, &pctx->ms_addr_ip4, pctx);
1031 static void pdp_context_free(struct rcu_head *head)
1033 struct pdp_ctx *pctx = container_of(head, struct pdp_ctx, rcu_head);
1039 static void pdp_context_delete(struct pdp_ctx *pctx)
1041 hlist_del_rcu(&pctx->hlist_tid);
1042 hlist_del_rcu(&pctx->hlist_addr);
1043 call_rcu(&pctx->rcu_head, pdp_context_free);
1046 static int gtp_genl_new_pdp(struct sk_buff *skb, struct genl_info *info)
1048 unsigned int version;
1049 struct gtp_dev *gtp;
1053 if (!info->attrs[GTPA_VERSION] ||
1054 !info->attrs[GTPA_LINK] ||
1055 !info->attrs[GTPA_PEER_ADDRESS] ||
1056 !info->attrs[GTPA_MS_ADDRESS])
1059 version = nla_get_u32(info->attrs[GTPA_VERSION]);
1063 if (!info->attrs[GTPA_TID] ||
1064 !info->attrs[GTPA_FLOW])
1068 if (!info->attrs[GTPA_I_TEI] ||
1069 !info->attrs[GTPA_O_TEI])
1080 gtp = gtp_find_dev(sock_net(skb->sk), info->attrs);
1086 if (version == GTP_V0)
1088 else if (version == GTP_V1)
1098 err = gtp_pdp_add(gtp, sk, info);
1106 static struct pdp_ctx *gtp_find_pdp_by_link(struct net *net,
1107 struct nlattr *nla[])
1109 struct gtp_dev *gtp;
1111 gtp = gtp_find_dev(net, nla);
1113 return ERR_PTR(-ENODEV);
1115 if (nla[GTPA_MS_ADDRESS]) {
1116 __be32 ip = nla_get_be32(nla[GTPA_MS_ADDRESS]);
1118 return ipv4_pdp_find(gtp, ip);
1119 } else if (nla[GTPA_VERSION]) {
1120 u32 gtp_version = nla_get_u32(nla[GTPA_VERSION]);
1122 if (gtp_version == GTP_V0 && nla[GTPA_TID])
1123 return gtp0_pdp_find(gtp, nla_get_u64(nla[GTPA_TID]));
1124 else if (gtp_version == GTP_V1 && nla[GTPA_I_TEI])
1125 return gtp1_pdp_find(gtp, nla_get_u32(nla[GTPA_I_TEI]));
1128 return ERR_PTR(-EINVAL);
1131 static struct pdp_ctx *gtp_find_pdp(struct net *net, struct nlattr *nla[])
1133 struct pdp_ctx *pctx;
1136 pctx = gtp_find_pdp_by_link(net, nla);
1138 pctx = ERR_PTR(-EINVAL);
1141 pctx = ERR_PTR(-ENOENT);
1146 static int gtp_genl_del_pdp(struct sk_buff *skb, struct genl_info *info)
1148 struct pdp_ctx *pctx;
1151 if (!info->attrs[GTPA_VERSION])
1156 pctx = gtp_find_pdp(sock_net(skb->sk), info->attrs);
1158 err = PTR_ERR(pctx);
1162 if (pctx->gtp_version == GTP_V0)
1163 netdev_dbg(pctx->dev, "GTPv0-U: deleting tunnel id = %llx (pdp %p)\n",
1164 pctx->u.v0.tid, pctx);
1165 else if (pctx->gtp_version == GTP_V1)
1166 netdev_dbg(pctx->dev, "GTPv1-U: deleting tunnel id = %x/%x (pdp %p)\n",
1167 pctx->u.v1.i_tei, pctx->u.v1.o_tei, pctx);
1169 pdp_context_delete(pctx);
1176 static struct genl_family gtp_genl_family;
1178 static int gtp_genl_fill_info(struct sk_buff *skb, u32 snd_portid, u32 snd_seq,
1179 int flags, u32 type, struct pdp_ctx *pctx)
1183 genlh = genlmsg_put(skb, snd_portid, snd_seq, >p_genl_family, flags,
1188 if (nla_put_u32(skb, GTPA_VERSION, pctx->gtp_version) ||
1189 nla_put_u32(skb, GTPA_LINK, pctx->dev->ifindex) ||
1190 nla_put_be32(skb, GTPA_PEER_ADDRESS, pctx->peer_addr_ip4.s_addr) ||
1191 nla_put_be32(skb, GTPA_MS_ADDRESS, pctx->ms_addr_ip4.s_addr))
1192 goto nla_put_failure;
1194 switch (pctx->gtp_version) {
1196 if (nla_put_u64_64bit(skb, GTPA_TID, pctx->u.v0.tid, GTPA_PAD) ||
1197 nla_put_u16(skb, GTPA_FLOW, pctx->u.v0.flow))
1198 goto nla_put_failure;
1201 if (nla_put_u32(skb, GTPA_I_TEI, pctx->u.v1.i_tei) ||
1202 nla_put_u32(skb, GTPA_O_TEI, pctx->u.v1.o_tei))
1203 goto nla_put_failure;
1206 genlmsg_end(skb, genlh);
1211 genlmsg_cancel(skb, genlh);
1215 static int gtp_genl_get_pdp(struct sk_buff *skb, struct genl_info *info)
1217 struct pdp_ctx *pctx = NULL;
1218 struct sk_buff *skb2;
1221 if (!info->attrs[GTPA_VERSION])
1226 pctx = gtp_find_pdp(sock_net(skb->sk), info->attrs);
1228 err = PTR_ERR(pctx);
1232 skb2 = genlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC);
1238 err = gtp_genl_fill_info(skb2, NETLINK_CB(skb).portid, info->snd_seq,
1239 0, info->nlhdr->nlmsg_type, pctx);
1241 goto err_unlock_free;
1244 return genlmsg_unicast(genl_info_net(info), skb2, info->snd_portid);
1253 static int gtp_genl_dump_pdp(struct sk_buff *skb,
1254 struct netlink_callback *cb)
1256 struct gtp_dev *last_gtp = (struct gtp_dev *)cb->args[2], *gtp;
1257 int i, j, bucket = cb->args[0], skip = cb->args[1];
1258 struct net *net = sock_net(skb->sk);
1259 struct pdp_ctx *pctx;
1262 gn = net_generic(net, gtp_net_id);
1268 list_for_each_entry_rcu(gtp, &gn->gtp_dev_list, list) {
1269 if (last_gtp && last_gtp != gtp)
1274 for (i = bucket; i < gtp->hash_size; i++) {
1276 hlist_for_each_entry_rcu(pctx, >p->tid_hash[i],
1279 gtp_genl_fill_info(skb,
1280 NETLINK_CB(cb->skb).portid,
1283 cb->nlh->nlmsg_type, pctx)) {
1286 cb->args[2] = (unsigned long)gtp;
1301 static const struct nla_policy gtp_genl_policy[GTPA_MAX + 1] = {
1302 [GTPA_LINK] = { .type = NLA_U32, },
1303 [GTPA_VERSION] = { .type = NLA_U32, },
1304 [GTPA_TID] = { .type = NLA_U64, },
1305 [GTPA_PEER_ADDRESS] = { .type = NLA_U32, },
1306 [GTPA_MS_ADDRESS] = { .type = NLA_U32, },
1307 [GTPA_FLOW] = { .type = NLA_U16, },
1308 [GTPA_NET_NS_FD] = { .type = NLA_U32, },
1309 [GTPA_I_TEI] = { .type = NLA_U32, },
1310 [GTPA_O_TEI] = { .type = NLA_U32, },
1313 static const struct genl_ops gtp_genl_ops[] = {
1315 .cmd = GTP_CMD_NEWPDP,
1316 .doit = gtp_genl_new_pdp,
1317 .policy = gtp_genl_policy,
1318 .flags = GENL_ADMIN_PERM,
1321 .cmd = GTP_CMD_DELPDP,
1322 .doit = gtp_genl_del_pdp,
1323 .policy = gtp_genl_policy,
1324 .flags = GENL_ADMIN_PERM,
1327 .cmd = GTP_CMD_GETPDP,
1328 .doit = gtp_genl_get_pdp,
1329 .dumpit = gtp_genl_dump_pdp,
1330 .policy = gtp_genl_policy,
1331 .flags = GENL_ADMIN_PERM,
1335 static struct genl_family gtp_genl_family __ro_after_init = {
1339 .maxattr = GTPA_MAX,
1341 .module = THIS_MODULE,
1342 .ops = gtp_genl_ops,
1343 .n_ops = ARRAY_SIZE(gtp_genl_ops),
1346 static int __net_init gtp_net_init(struct net *net)
1348 struct gtp_net *gn = net_generic(net, gtp_net_id);
1350 INIT_LIST_HEAD(&gn->gtp_dev_list);
1354 static void __net_exit gtp_net_exit(struct net *net)
1356 struct gtp_net *gn = net_generic(net, gtp_net_id);
1357 struct gtp_dev *gtp;
1361 list_for_each_entry(gtp, &gn->gtp_dev_list, list)
1362 gtp_dellink(gtp->dev, &list);
1364 unregister_netdevice_many(&list);
1368 static struct pernet_operations gtp_net_ops = {
1369 .init = gtp_net_init,
1370 .exit = gtp_net_exit,
1372 .size = sizeof(struct gtp_net),
1375 static int __init gtp_init(void)
1379 get_random_bytes(>p_h_initval, sizeof(gtp_h_initval));
1381 err = rtnl_link_register(>p_link_ops);
1385 err = genl_register_family(>p_genl_family);
1387 goto unreg_rtnl_link;
1389 err = register_pernet_subsys(>p_net_ops);
1391 goto unreg_genl_family;
1393 pr_info("GTP module loaded (pdp ctx size %zd bytes)\n",
1394 sizeof(struct pdp_ctx));
1398 genl_unregister_family(>p_genl_family);
1400 rtnl_link_unregister(>p_link_ops);
1402 pr_err("error loading GTP module loaded\n");
1405 late_initcall(gtp_init);
1407 static void __exit gtp_fini(void)
1409 genl_unregister_family(>p_genl_family);
1410 rtnl_link_unregister(>p_link_ops);
1411 unregister_pernet_subsys(>p_net_ops);
1413 pr_info("GTP module unloaded\n");
1415 module_exit(gtp_fini);
1417 MODULE_LICENSE("GPL");
1418 MODULE_AUTHOR("Harald Welte <hwelte@sysmocom.de>");
1419 MODULE_DESCRIPTION("Interface driver for GTP encapsulated traffic");
1420 MODULE_ALIAS_RTNL_LINK("gtp");
1421 MODULE_ALIAS_GENL_FAMILY("gtp");