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 (iph->frag_off & htons(IP_DF) &&
552 ((!skb_is_gso(skb) && skb->len > mtu) ||
553 (skb_is_gso(skb) && !skb_gso_validate_network_len(skb, mtu)))) {
554 netdev_dbg(dev, "packet too big, fragmentation needed\n");
555 icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
560 gtp_set_pktinfo_ipv4(pktinfo, pctx->sk, iph, pctx, rt, &fl4, dev);
561 gtp_push_header(skb, pktinfo);
570 static netdev_tx_t gtp_dev_xmit(struct sk_buff *skb, struct net_device *dev)
572 unsigned int proto = ntohs(skb->protocol);
573 struct gtp_pktinfo pktinfo;
576 /* Ensure there is sufficient headroom. */
577 if (skb_cow_head(skb, dev->needed_headroom))
580 skb_reset_inner_headers(skb);
582 /* PDP context lookups in gtp_build_skb_*() need rcu read-side lock. */
586 err = gtp_build_skb_ip4(skb, dev, &pktinfo);
599 netdev_dbg(pktinfo.dev, "gtp -> IP src: %pI4 dst: %pI4\n",
600 &pktinfo.iph->saddr, &pktinfo.iph->daddr);
601 udp_tunnel_xmit_skb(pktinfo.rt, pktinfo.sk, skb,
602 pktinfo.fl4.saddr, pktinfo.fl4.daddr,
604 ip4_dst_hoplimit(&pktinfo.rt->dst),
606 pktinfo.gtph_port, pktinfo.gtph_port,
613 dev->stats.tx_errors++;
618 static const struct net_device_ops gtp_netdev_ops = {
619 .ndo_init = gtp_dev_init,
620 .ndo_uninit = gtp_dev_uninit,
621 .ndo_start_xmit = gtp_dev_xmit,
622 .ndo_get_stats64 = ip_tunnel_get_stats64,
625 static void gtp_link_setup(struct net_device *dev)
627 dev->netdev_ops = >p_netdev_ops;
628 dev->needs_free_netdev = true;
630 dev->hard_header_len = 0;
633 /* Zero header length. */
634 dev->type = ARPHRD_NONE;
635 dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
637 dev->priv_flags |= IFF_NO_QUEUE;
638 dev->features |= NETIF_F_LLTX;
641 /* Assume largest header, ie. GTPv0. */
642 dev->needed_headroom = LL_MAX_HEADER +
643 sizeof(struct iphdr) +
644 sizeof(struct udphdr) +
645 sizeof(struct gtp0_header);
648 static int gtp_hashtable_new(struct gtp_dev *gtp, int hsize);
649 static int gtp_encap_enable(struct gtp_dev *gtp, struct nlattr *data[]);
651 static void gtp_destructor(struct net_device *dev)
653 struct gtp_dev *gtp = netdev_priv(dev);
655 kfree(gtp->addr_hash);
656 kfree(gtp->tid_hash);
659 static int gtp_newlink(struct net *src_net, struct net_device *dev,
660 struct nlattr *tb[], struct nlattr *data[],
661 struct netlink_ext_ack *extack)
667 if (!data[IFLA_GTP_FD0] && !data[IFLA_GTP_FD1])
670 gtp = netdev_priv(dev);
672 if (!data[IFLA_GTP_PDP_HASHSIZE]) {
675 hashsize = nla_get_u32(data[IFLA_GTP_PDP_HASHSIZE]);
680 err = gtp_hashtable_new(gtp, hashsize);
684 err = gtp_encap_enable(gtp, data);
688 err = register_netdevice(dev);
690 netdev_dbg(dev, "failed to register new netdev %d\n", err);
694 gn = net_generic(dev_net(dev), gtp_net_id);
695 list_add_rcu(>p->list, &gn->gtp_dev_list);
696 dev->priv_destructor = gtp_destructor;
698 netdev_dbg(dev, "registered new GTP interface\n");
703 gtp_encap_disable(gtp);
705 kfree(gtp->addr_hash);
706 kfree(gtp->tid_hash);
710 static void gtp_dellink(struct net_device *dev, struct list_head *head)
712 struct gtp_dev *gtp = netdev_priv(dev);
713 struct hlist_node *next;
714 struct pdp_ctx *pctx;
717 for (i = 0; i < gtp->hash_size; i++)
718 hlist_for_each_entry_safe(pctx, next, >p->tid_hash[i], hlist_tid)
719 pdp_context_delete(pctx);
721 gtp_encap_disable(gtp);
722 list_del_rcu(>p->list);
723 unregister_netdevice_queue(dev, head);
726 static const struct nla_policy gtp_policy[IFLA_GTP_MAX + 1] = {
727 [IFLA_GTP_FD0] = { .type = NLA_U32 },
728 [IFLA_GTP_FD1] = { .type = NLA_U32 },
729 [IFLA_GTP_PDP_HASHSIZE] = { .type = NLA_U32 },
730 [IFLA_GTP_ROLE] = { .type = NLA_U32 },
733 static int gtp_validate(struct nlattr *tb[], struct nlattr *data[],
734 struct netlink_ext_ack *extack)
742 static size_t gtp_get_size(const struct net_device *dev)
744 return nla_total_size(sizeof(__u32)); /* IFLA_GTP_PDP_HASHSIZE */
747 static int gtp_fill_info(struct sk_buff *skb, const struct net_device *dev)
749 struct gtp_dev *gtp = netdev_priv(dev);
751 if (nla_put_u32(skb, IFLA_GTP_PDP_HASHSIZE, gtp->hash_size))
752 goto nla_put_failure;
760 static struct rtnl_link_ops gtp_link_ops __read_mostly = {
762 .maxtype = IFLA_GTP_MAX,
763 .policy = gtp_policy,
764 .priv_size = sizeof(struct gtp_dev),
765 .setup = gtp_link_setup,
766 .validate = gtp_validate,
767 .newlink = gtp_newlink,
768 .dellink = gtp_dellink,
769 .get_size = gtp_get_size,
770 .fill_info = gtp_fill_info,
773 static int gtp_hashtable_new(struct gtp_dev *gtp, int hsize)
777 gtp->addr_hash = kmalloc_array(hsize, sizeof(struct hlist_head),
778 GFP_KERNEL | __GFP_NOWARN);
779 if (gtp->addr_hash == NULL)
782 gtp->tid_hash = kmalloc_array(hsize, sizeof(struct hlist_head),
783 GFP_KERNEL | __GFP_NOWARN);
784 if (gtp->tid_hash == NULL)
787 gtp->hash_size = hsize;
789 for (i = 0; i < hsize; i++) {
790 INIT_HLIST_HEAD(>p->addr_hash[i]);
791 INIT_HLIST_HEAD(>p->tid_hash[i]);
795 kfree(gtp->addr_hash);
799 static struct sock *gtp_encap_enable_socket(int fd, int type,
802 struct udp_tunnel_sock_cfg tuncfg = {NULL};
807 pr_debug("enable gtp on %d, %d\n", fd, type);
809 sock = sockfd_lookup(fd, &err);
811 pr_debug("gtp socket fd=%d not found\n", fd);
816 if (sk->sk_protocol != IPPROTO_UDP ||
817 sk->sk_type != SOCK_DGRAM ||
818 (sk->sk_family != AF_INET && sk->sk_family != AF_INET6)) {
819 pr_debug("socket fd=%d not UDP\n", fd);
820 sk = ERR_PTR(-EINVAL);
825 if (sk->sk_user_data) {
826 sk = ERR_PTR(-EBUSY);
832 tuncfg.sk_user_data = gtp;
833 tuncfg.encap_type = type;
834 tuncfg.encap_rcv = gtp_encap_recv;
835 tuncfg.encap_destroy = gtp_encap_destroy;
837 setup_udp_tunnel_sock(sock_net(sock->sk), sock, &tuncfg);
840 release_sock(sock->sk);
846 static int gtp_encap_enable(struct gtp_dev *gtp, struct nlattr *data[])
848 struct sock *sk1u = NULL;
849 struct sock *sk0 = NULL;
850 unsigned int role = GTP_ROLE_GGSN;
852 if (data[IFLA_GTP_FD0]) {
853 u32 fd0 = nla_get_u32(data[IFLA_GTP_FD0]);
855 sk0 = gtp_encap_enable_socket(fd0, UDP_ENCAP_GTP0, gtp);
860 if (data[IFLA_GTP_FD1]) {
861 u32 fd1 = nla_get_u32(data[IFLA_GTP_FD1]);
863 sk1u = gtp_encap_enable_socket(fd1, UDP_ENCAP_GTP1U, gtp);
866 gtp_encap_disable_sock(sk0);
867 return PTR_ERR(sk1u);
871 if (data[IFLA_GTP_ROLE]) {
872 role = nla_get_u32(data[IFLA_GTP_ROLE]);
873 if (role > GTP_ROLE_SGSN) {
875 gtp_encap_disable_sock(sk0);
877 gtp_encap_disable_sock(sk1u);
889 static struct gtp_dev *gtp_find_dev(struct net *src_net, struct nlattr *nla[])
891 struct gtp_dev *gtp = NULL;
892 struct net_device *dev;
895 /* Examine the link attributes and figure out which network namespace
896 * we are talking about.
898 if (nla[GTPA_NET_NS_FD])
899 net = get_net_ns_by_fd(nla_get_u32(nla[GTPA_NET_NS_FD]));
901 net = get_net(src_net);
906 /* Check if there's an existing gtpX device to configure */
907 dev = dev_get_by_index_rcu(net, nla_get_u32(nla[GTPA_LINK]));
908 if (dev && dev->netdev_ops == >p_netdev_ops)
909 gtp = netdev_priv(dev);
915 static void ipv4_pdp_fill(struct pdp_ctx *pctx, struct genl_info *info)
917 pctx->gtp_version = nla_get_u32(info->attrs[GTPA_VERSION]);
919 pctx->peer_addr_ip4.s_addr =
920 nla_get_be32(info->attrs[GTPA_PEER_ADDRESS]);
921 pctx->ms_addr_ip4.s_addr =
922 nla_get_be32(info->attrs[GTPA_MS_ADDRESS]);
924 switch (pctx->gtp_version) {
926 /* According to TS 09.60, sections 7.5.1 and 7.5.2, the flow
927 * label needs to be the same for uplink and downlink packets,
928 * so let's annotate this.
930 pctx->u.v0.tid = nla_get_u64(info->attrs[GTPA_TID]);
931 pctx->u.v0.flow = nla_get_u16(info->attrs[GTPA_FLOW]);
934 pctx->u.v1.i_tei = nla_get_u32(info->attrs[GTPA_I_TEI]);
935 pctx->u.v1.o_tei = nla_get_u32(info->attrs[GTPA_O_TEI]);
942 static int gtp_pdp_add(struct gtp_dev *gtp, struct sock *sk,
943 struct genl_info *info)
945 struct pdp_ctx *pctx, *pctx_tid = NULL;
946 struct net_device *dev = gtp->dev;
947 u32 hash_ms, hash_tid = 0;
948 unsigned int version;
952 ms_addr = nla_get_be32(info->attrs[GTPA_MS_ADDRESS]);
953 hash_ms = ipv4_hashfn(ms_addr) % gtp->hash_size;
954 version = nla_get_u32(info->attrs[GTPA_VERSION]);
956 pctx = ipv4_pdp_find(gtp, ms_addr);
959 if (version == GTP_V0)
960 pctx_tid = gtp0_pdp_find(gtp,
961 nla_get_u64(info->attrs[GTPA_TID]));
962 else if (version == GTP_V1)
963 pctx_tid = gtp1_pdp_find(gtp,
964 nla_get_u32(info->attrs[GTPA_I_TEI]));
969 if (info->nlhdr->nlmsg_flags & NLM_F_EXCL)
971 if (info->nlhdr->nlmsg_flags & NLM_F_REPLACE)
974 if (pctx && pctx_tid)
979 ipv4_pdp_fill(pctx, info);
981 if (pctx->gtp_version == GTP_V0)
982 netdev_dbg(dev, "GTPv0-U: update tunnel id = %llx (pdp %p)\n",
983 pctx->u.v0.tid, pctx);
984 else if (pctx->gtp_version == GTP_V1)
985 netdev_dbg(dev, "GTPv1-U: update tunnel id = %x/%x (pdp %p)\n",
986 pctx->u.v1.i_tei, pctx->u.v1.o_tei, pctx);
992 pctx = kmalloc(sizeof(*pctx), GFP_ATOMIC);
998 pctx->dev = gtp->dev;
999 ipv4_pdp_fill(pctx, info);
1000 atomic_set(&pctx->tx_seq, 0);
1002 switch (pctx->gtp_version) {
1004 /* TS 09.60: "The flow label identifies unambiguously a GTP
1005 * flow.". We use the tid for this instead, I cannot find a
1006 * situation in which this doesn't unambiguosly identify the
1009 hash_tid = gtp0_hashfn(pctx->u.v0.tid) % gtp->hash_size;
1012 hash_tid = gtp1u_hashfn(pctx->u.v1.i_tei) % gtp->hash_size;
1016 hlist_add_head_rcu(&pctx->hlist_addr, >p->addr_hash[hash_ms]);
1017 hlist_add_head_rcu(&pctx->hlist_tid, >p->tid_hash[hash_tid]);
1019 switch (pctx->gtp_version) {
1021 netdev_dbg(dev, "GTPv0-U: new PDP ctx id=%llx ssgn=%pI4 ms=%pI4 (pdp=%p)\n",
1022 pctx->u.v0.tid, &pctx->peer_addr_ip4,
1023 &pctx->ms_addr_ip4, pctx);
1026 netdev_dbg(dev, "GTPv1-U: new PDP ctx id=%x/%x ssgn=%pI4 ms=%pI4 (pdp=%p)\n",
1027 pctx->u.v1.i_tei, pctx->u.v1.o_tei,
1028 &pctx->peer_addr_ip4, &pctx->ms_addr_ip4, pctx);
1035 static void pdp_context_free(struct rcu_head *head)
1037 struct pdp_ctx *pctx = container_of(head, struct pdp_ctx, rcu_head);
1043 static void pdp_context_delete(struct pdp_ctx *pctx)
1045 hlist_del_rcu(&pctx->hlist_tid);
1046 hlist_del_rcu(&pctx->hlist_addr);
1047 call_rcu(&pctx->rcu_head, pdp_context_free);
1050 static int gtp_genl_new_pdp(struct sk_buff *skb, struct genl_info *info)
1052 unsigned int version;
1053 struct gtp_dev *gtp;
1057 if (!info->attrs[GTPA_VERSION] ||
1058 !info->attrs[GTPA_LINK] ||
1059 !info->attrs[GTPA_PEER_ADDRESS] ||
1060 !info->attrs[GTPA_MS_ADDRESS])
1063 version = nla_get_u32(info->attrs[GTPA_VERSION]);
1067 if (!info->attrs[GTPA_TID] ||
1068 !info->attrs[GTPA_FLOW])
1072 if (!info->attrs[GTPA_I_TEI] ||
1073 !info->attrs[GTPA_O_TEI])
1084 gtp = gtp_find_dev(sock_net(skb->sk), info->attrs);
1090 if (version == GTP_V0)
1092 else if (version == GTP_V1)
1102 err = gtp_pdp_add(gtp, sk, info);
1110 static struct pdp_ctx *gtp_find_pdp_by_link(struct net *net,
1111 struct nlattr *nla[])
1113 struct gtp_dev *gtp;
1115 gtp = gtp_find_dev(net, nla);
1117 return ERR_PTR(-ENODEV);
1119 if (nla[GTPA_MS_ADDRESS]) {
1120 __be32 ip = nla_get_be32(nla[GTPA_MS_ADDRESS]);
1122 return ipv4_pdp_find(gtp, ip);
1123 } else if (nla[GTPA_VERSION]) {
1124 u32 gtp_version = nla_get_u32(nla[GTPA_VERSION]);
1126 if (gtp_version == GTP_V0 && nla[GTPA_TID])
1127 return gtp0_pdp_find(gtp, nla_get_u64(nla[GTPA_TID]));
1128 else if (gtp_version == GTP_V1 && nla[GTPA_I_TEI])
1129 return gtp1_pdp_find(gtp, nla_get_u32(nla[GTPA_I_TEI]));
1132 return ERR_PTR(-EINVAL);
1135 static struct pdp_ctx *gtp_find_pdp(struct net *net, struct nlattr *nla[])
1137 struct pdp_ctx *pctx;
1140 pctx = gtp_find_pdp_by_link(net, nla);
1142 pctx = ERR_PTR(-EINVAL);
1145 pctx = ERR_PTR(-ENOENT);
1150 static int gtp_genl_del_pdp(struct sk_buff *skb, struct genl_info *info)
1152 struct pdp_ctx *pctx;
1155 if (!info->attrs[GTPA_VERSION])
1160 pctx = gtp_find_pdp(sock_net(skb->sk), info->attrs);
1162 err = PTR_ERR(pctx);
1166 if (pctx->gtp_version == GTP_V0)
1167 netdev_dbg(pctx->dev, "GTPv0-U: deleting tunnel id = %llx (pdp %p)\n",
1168 pctx->u.v0.tid, pctx);
1169 else if (pctx->gtp_version == GTP_V1)
1170 netdev_dbg(pctx->dev, "GTPv1-U: deleting tunnel id = %x/%x (pdp %p)\n",
1171 pctx->u.v1.i_tei, pctx->u.v1.o_tei, pctx);
1173 pdp_context_delete(pctx);
1180 static struct genl_family gtp_genl_family;
1182 static int gtp_genl_fill_info(struct sk_buff *skb, u32 snd_portid, u32 snd_seq,
1183 int flags, u32 type, struct pdp_ctx *pctx)
1187 genlh = genlmsg_put(skb, snd_portid, snd_seq, >p_genl_family, flags,
1192 if (nla_put_u32(skb, GTPA_VERSION, pctx->gtp_version) ||
1193 nla_put_u32(skb, GTPA_LINK, pctx->dev->ifindex) ||
1194 nla_put_be32(skb, GTPA_PEER_ADDRESS, pctx->peer_addr_ip4.s_addr) ||
1195 nla_put_be32(skb, GTPA_MS_ADDRESS, pctx->ms_addr_ip4.s_addr))
1196 goto nla_put_failure;
1198 switch (pctx->gtp_version) {
1200 if (nla_put_u64_64bit(skb, GTPA_TID, pctx->u.v0.tid, GTPA_PAD) ||
1201 nla_put_u16(skb, GTPA_FLOW, pctx->u.v0.flow))
1202 goto nla_put_failure;
1205 if (nla_put_u32(skb, GTPA_I_TEI, pctx->u.v1.i_tei) ||
1206 nla_put_u32(skb, GTPA_O_TEI, pctx->u.v1.o_tei))
1207 goto nla_put_failure;
1210 genlmsg_end(skb, genlh);
1215 genlmsg_cancel(skb, genlh);
1219 static int gtp_genl_get_pdp(struct sk_buff *skb, struct genl_info *info)
1221 struct pdp_ctx *pctx = NULL;
1222 struct sk_buff *skb2;
1225 if (!info->attrs[GTPA_VERSION])
1230 pctx = gtp_find_pdp(sock_net(skb->sk), info->attrs);
1232 err = PTR_ERR(pctx);
1236 skb2 = genlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC);
1242 err = gtp_genl_fill_info(skb2, NETLINK_CB(skb).portid, info->snd_seq,
1243 0, info->nlhdr->nlmsg_type, pctx);
1245 goto err_unlock_free;
1248 return genlmsg_unicast(genl_info_net(info), skb2, info->snd_portid);
1257 static int gtp_genl_dump_pdp(struct sk_buff *skb,
1258 struct netlink_callback *cb)
1260 struct gtp_dev *last_gtp = (struct gtp_dev *)cb->args[2], *gtp;
1261 int i, j, bucket = cb->args[0], skip = cb->args[1];
1262 struct net *net = sock_net(skb->sk);
1263 struct pdp_ctx *pctx;
1266 gn = net_generic(net, gtp_net_id);
1272 list_for_each_entry_rcu(gtp, &gn->gtp_dev_list, list) {
1273 if (last_gtp && last_gtp != gtp)
1278 for (i = bucket; i < gtp->hash_size; i++) {
1280 hlist_for_each_entry_rcu(pctx, >p->tid_hash[i],
1283 gtp_genl_fill_info(skb,
1284 NETLINK_CB(cb->skb).portid,
1287 cb->nlh->nlmsg_type, pctx)) {
1290 cb->args[2] = (unsigned long)gtp;
1305 static const struct nla_policy gtp_genl_policy[GTPA_MAX + 1] = {
1306 [GTPA_LINK] = { .type = NLA_U32, },
1307 [GTPA_VERSION] = { .type = NLA_U32, },
1308 [GTPA_TID] = { .type = NLA_U64, },
1309 [GTPA_PEER_ADDRESS] = { .type = NLA_U32, },
1310 [GTPA_MS_ADDRESS] = { .type = NLA_U32, },
1311 [GTPA_FLOW] = { .type = NLA_U16, },
1312 [GTPA_NET_NS_FD] = { .type = NLA_U32, },
1313 [GTPA_I_TEI] = { .type = NLA_U32, },
1314 [GTPA_O_TEI] = { .type = NLA_U32, },
1317 static const struct genl_ops gtp_genl_ops[] = {
1319 .cmd = GTP_CMD_NEWPDP,
1320 .doit = gtp_genl_new_pdp,
1321 .policy = gtp_genl_policy,
1322 .flags = GENL_ADMIN_PERM,
1325 .cmd = GTP_CMD_DELPDP,
1326 .doit = gtp_genl_del_pdp,
1327 .policy = gtp_genl_policy,
1328 .flags = GENL_ADMIN_PERM,
1331 .cmd = GTP_CMD_GETPDP,
1332 .doit = gtp_genl_get_pdp,
1333 .dumpit = gtp_genl_dump_pdp,
1334 .policy = gtp_genl_policy,
1335 .flags = GENL_ADMIN_PERM,
1339 static struct genl_family gtp_genl_family __ro_after_init = {
1343 .maxattr = GTPA_MAX,
1345 .module = THIS_MODULE,
1346 .ops = gtp_genl_ops,
1347 .n_ops = ARRAY_SIZE(gtp_genl_ops),
1350 static int __net_init gtp_net_init(struct net *net)
1352 struct gtp_net *gn = net_generic(net, gtp_net_id);
1354 INIT_LIST_HEAD(&gn->gtp_dev_list);
1358 static void __net_exit gtp_net_exit(struct net *net)
1360 struct gtp_net *gn = net_generic(net, gtp_net_id);
1361 struct gtp_dev *gtp;
1365 list_for_each_entry(gtp, &gn->gtp_dev_list, list)
1366 gtp_dellink(gtp->dev, &list);
1368 unregister_netdevice_many(&list);
1372 static struct pernet_operations gtp_net_ops = {
1373 .init = gtp_net_init,
1374 .exit = gtp_net_exit,
1376 .size = sizeof(struct gtp_net),
1379 static int __init gtp_init(void)
1383 get_random_bytes(>p_h_initval, sizeof(gtp_h_initval));
1385 err = register_pernet_subsys(>p_net_ops);
1389 err = rtnl_link_register(>p_link_ops);
1391 goto unreg_pernet_subsys;
1393 err = genl_register_family(>p_genl_family);
1395 goto unreg_rtnl_link;
1397 pr_info("GTP module loaded (pdp ctx size %zd bytes)\n",
1398 sizeof(struct pdp_ctx));
1402 rtnl_link_unregister(>p_link_ops);
1403 unreg_pernet_subsys:
1404 unregister_pernet_subsys(>p_net_ops);
1406 pr_err("error loading GTP module loaded\n");
1409 late_initcall(gtp_init);
1411 static void __exit gtp_fini(void)
1413 genl_unregister_family(>p_genl_family);
1414 rtnl_link_unregister(>p_link_ops);
1415 unregister_pernet_subsys(>p_net_ops);
1417 pr_info("GTP module unloaded\n");
1419 module_exit(gtp_fini);
1421 MODULE_LICENSE("GPL");
1422 MODULE_AUTHOR("Harald Welte <hwelte@sysmocom.de>");
1423 MODULE_DESCRIPTION("Interface driver for GTP encapsulated traffic");
1424 MODULE_ALIAS_RTNL_LINK("gtp");
1425 MODULE_ALIAS_GENL_FAMILY("gtp");