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 memset(IPCB(skb
), 0, sizeof(*IPCB(skb
)));
553 icmp_send(skb
, ICMP_DEST_UNREACH
, ICMP_FRAG_NEEDED
,
558 gtp_set_pktinfo_ipv4(pktinfo
, pctx
->sk
, iph
, pctx
, rt
, &fl4
, dev
);
559 gtp_push_header(skb
, pktinfo
);
568 static netdev_tx_t
gtp_dev_xmit(struct sk_buff
*skb
, struct net_device
*dev
)
570 unsigned int proto
= ntohs(skb
->protocol
);
571 struct gtp_pktinfo pktinfo
;
574 /* Ensure there is sufficient headroom. */
575 if (skb_cow_head(skb
, dev
->needed_headroom
))
578 skb_reset_inner_headers(skb
);
580 /* PDP context lookups in gtp_build_skb_*() need rcu read-side lock. */
584 err
= gtp_build_skb_ip4(skb
, dev
, &pktinfo
);
597 netdev_dbg(pktinfo
.dev
, "gtp -> IP src: %pI4 dst: %pI4\n",
598 &pktinfo
.iph
->saddr
, &pktinfo
.iph
->daddr
);
599 udp_tunnel_xmit_skb(pktinfo
.rt
, pktinfo
.sk
, skb
,
600 pktinfo
.fl4
.saddr
, pktinfo
.fl4
.daddr
,
602 ip4_dst_hoplimit(&pktinfo
.rt
->dst
),
604 pktinfo
.gtph_port
, pktinfo
.gtph_port
,
611 dev
->stats
.tx_errors
++;
616 static const struct net_device_ops gtp_netdev_ops
= {
617 .ndo_init
= gtp_dev_init
,
618 .ndo_uninit
= gtp_dev_uninit
,
619 .ndo_start_xmit
= gtp_dev_xmit
,
620 .ndo_get_stats64
= ip_tunnel_get_stats64
,
623 static void gtp_link_setup(struct net_device
*dev
)
625 dev
->netdev_ops
= >p_netdev_ops
;
626 dev
->needs_free_netdev
= true;
628 dev
->hard_header_len
= 0;
631 /* Zero header length. */
632 dev
->type
= ARPHRD_NONE
;
633 dev
->flags
= IFF_POINTOPOINT
| IFF_NOARP
| IFF_MULTICAST
;
635 dev
->priv_flags
|= IFF_NO_QUEUE
;
636 dev
->features
|= NETIF_F_LLTX
;
639 /* Assume largest header, ie. GTPv0. */
640 dev
->needed_headroom
= LL_MAX_HEADER
+
641 sizeof(struct iphdr
) +
642 sizeof(struct udphdr
) +
643 sizeof(struct gtp0_header
);
646 static int gtp_hashtable_new(struct gtp_dev
*gtp
, int hsize
);
647 static int gtp_encap_enable(struct gtp_dev
*gtp
, struct nlattr
*data
[]);
649 static void gtp_destructor(struct net_device
*dev
)
651 struct gtp_dev
*gtp
= netdev_priv(dev
);
653 kfree(gtp
->addr_hash
);
654 kfree(gtp
->tid_hash
);
657 static int gtp_newlink(struct net
*src_net
, struct net_device
*dev
,
658 struct nlattr
*tb
[], struct nlattr
*data
[],
659 struct netlink_ext_ack
*extack
)
665 if (!data
[IFLA_GTP_FD0
] && !data
[IFLA_GTP_FD1
])
668 gtp
= netdev_priv(dev
);
670 err
= gtp_encap_enable(gtp
, data
);
674 if (!data
[IFLA_GTP_PDP_HASHSIZE
]) {
677 hashsize
= nla_get_u32(data
[IFLA_GTP_PDP_HASHSIZE
]);
682 err
= gtp_hashtable_new(gtp
, hashsize
);
686 err
= register_netdevice(dev
);
688 netdev_dbg(dev
, "failed to register new netdev %d\n", err
);
692 gn
= net_generic(dev_net(dev
), gtp_net_id
);
693 list_add_rcu(>p
->list
, &gn
->gtp_dev_list
);
694 dev
->priv_destructor
= gtp_destructor
;
696 netdev_dbg(dev
, "registered new GTP interface\n");
701 kfree(gtp
->addr_hash
);
702 kfree(gtp
->tid_hash
);
704 gtp_encap_disable(gtp
);
708 static void gtp_dellink(struct net_device
*dev
, struct list_head
*head
)
710 struct gtp_dev
*gtp
= netdev_priv(dev
);
711 struct pdp_ctx
*pctx
;
714 for (i
= 0; i
< gtp
->hash_size
; i
++)
715 hlist_for_each_entry_rcu(pctx
, >p
->tid_hash
[i
], hlist_tid
)
716 pdp_context_delete(pctx
);
718 gtp_encap_disable(gtp
);
719 list_del_rcu(>p
->list
);
720 unregister_netdevice_queue(dev
, head
);
723 static const struct nla_policy gtp_policy
[IFLA_GTP_MAX
+ 1] = {
724 [IFLA_GTP_FD0
] = { .type
= NLA_U32
},
725 [IFLA_GTP_FD1
] = { .type
= NLA_U32
},
726 [IFLA_GTP_PDP_HASHSIZE
] = { .type
= NLA_U32
},
727 [IFLA_GTP_ROLE
] = { .type
= NLA_U32
},
730 static int gtp_validate(struct nlattr
*tb
[], struct nlattr
*data
[],
731 struct netlink_ext_ack
*extack
)
739 static size_t gtp_get_size(const struct net_device
*dev
)
741 return nla_total_size(sizeof(__u32
)); /* IFLA_GTP_PDP_HASHSIZE */
744 static int gtp_fill_info(struct sk_buff
*skb
, const struct net_device
*dev
)
746 struct gtp_dev
*gtp
= netdev_priv(dev
);
748 if (nla_put_u32(skb
, IFLA_GTP_PDP_HASHSIZE
, gtp
->hash_size
))
749 goto nla_put_failure
;
757 static struct rtnl_link_ops gtp_link_ops __read_mostly
= {
759 .maxtype
= IFLA_GTP_MAX
,
760 .policy
= gtp_policy
,
761 .priv_size
= sizeof(struct gtp_dev
),
762 .setup
= gtp_link_setup
,
763 .validate
= gtp_validate
,
764 .newlink
= gtp_newlink
,
765 .dellink
= gtp_dellink
,
766 .get_size
= gtp_get_size
,
767 .fill_info
= gtp_fill_info
,
770 static int gtp_hashtable_new(struct gtp_dev
*gtp
, int hsize
)
774 gtp
->addr_hash
= kmalloc_array(hsize
, sizeof(struct hlist_head
),
775 GFP_KERNEL
| __GFP_NOWARN
);
776 if (gtp
->addr_hash
== NULL
)
779 gtp
->tid_hash
= kmalloc_array(hsize
, sizeof(struct hlist_head
),
780 GFP_KERNEL
| __GFP_NOWARN
);
781 if (gtp
->tid_hash
== NULL
)
784 gtp
->hash_size
= hsize
;
786 for (i
= 0; i
< hsize
; i
++) {
787 INIT_HLIST_HEAD(>p
->addr_hash
[i
]);
788 INIT_HLIST_HEAD(>p
->tid_hash
[i
]);
792 kfree(gtp
->addr_hash
);
796 static struct sock
*gtp_encap_enable_socket(int fd
, int type
,
799 struct udp_tunnel_sock_cfg tuncfg
= {NULL
};
804 pr_debug("enable gtp on %d, %d\n", fd
, type
);
806 sock
= sockfd_lookup(fd
, &err
);
808 pr_debug("gtp socket fd=%d not found\n", fd
);
813 if (sk
->sk_protocol
!= IPPROTO_UDP
||
814 sk
->sk_type
!= SOCK_DGRAM
||
815 (sk
->sk_family
!= AF_INET
&& sk
->sk_family
!= AF_INET6
)) {
816 pr_debug("socket fd=%d not UDP\n", fd
);
817 sk
= ERR_PTR(-EINVAL
);
822 if (sk
->sk_user_data
) {
823 sk
= ERR_PTR(-EBUSY
);
829 tuncfg
.sk_user_data
= gtp
;
830 tuncfg
.encap_type
= type
;
831 tuncfg
.encap_rcv
= gtp_encap_recv
;
832 tuncfg
.encap_destroy
= gtp_encap_destroy
;
834 setup_udp_tunnel_sock(sock_net(sock
->sk
), sock
, &tuncfg
);
837 release_sock(sock
->sk
);
843 static int gtp_encap_enable(struct gtp_dev
*gtp
, struct nlattr
*data
[])
845 struct sock
*sk1u
= NULL
;
846 struct sock
*sk0
= NULL
;
847 unsigned int role
= GTP_ROLE_GGSN
;
849 if (data
[IFLA_GTP_FD0
]) {
850 u32 fd0
= nla_get_u32(data
[IFLA_GTP_FD0
]);
852 sk0
= gtp_encap_enable_socket(fd0
, UDP_ENCAP_GTP0
, gtp
);
857 if (data
[IFLA_GTP_FD1
]) {
858 u32 fd1
= nla_get_u32(data
[IFLA_GTP_FD1
]);
860 sk1u
= gtp_encap_enable_socket(fd1
, UDP_ENCAP_GTP1U
, gtp
);
863 gtp_encap_disable_sock(sk0
);
864 return PTR_ERR(sk1u
);
868 if (data
[IFLA_GTP_ROLE
]) {
869 role
= nla_get_u32(data
[IFLA_GTP_ROLE
]);
870 if (role
> GTP_ROLE_SGSN
) {
872 gtp_encap_disable_sock(sk0
);
874 gtp_encap_disable_sock(sk1u
);
886 static struct gtp_dev
*gtp_find_dev(struct net
*src_net
, struct nlattr
*nla
[])
888 struct gtp_dev
*gtp
= NULL
;
889 struct net_device
*dev
;
892 /* Examine the link attributes and figure out which network namespace
893 * we are talking about.
895 if (nla
[GTPA_NET_NS_FD
])
896 net
= get_net_ns_by_fd(nla_get_u32(nla
[GTPA_NET_NS_FD
]));
898 net
= get_net(src_net
);
903 /* Check if there's an existing gtpX device to configure */
904 dev
= dev_get_by_index_rcu(net
, nla_get_u32(nla
[GTPA_LINK
]));
905 if (dev
&& dev
->netdev_ops
== >p_netdev_ops
)
906 gtp
= netdev_priv(dev
);
912 static void ipv4_pdp_fill(struct pdp_ctx
*pctx
, struct genl_info
*info
)
914 pctx
->gtp_version
= nla_get_u32(info
->attrs
[GTPA_VERSION
]);
916 pctx
->peer_addr_ip4
.s_addr
=
917 nla_get_be32(info
->attrs
[GTPA_PEER_ADDRESS
]);
918 pctx
->ms_addr_ip4
.s_addr
=
919 nla_get_be32(info
->attrs
[GTPA_MS_ADDRESS
]);
921 switch (pctx
->gtp_version
) {
923 /* According to TS 09.60, sections 7.5.1 and 7.5.2, the flow
924 * label needs to be the same for uplink and downlink packets,
925 * so let's annotate this.
927 pctx
->u
.v0
.tid
= nla_get_u64(info
->attrs
[GTPA_TID
]);
928 pctx
->u
.v0
.flow
= nla_get_u16(info
->attrs
[GTPA_FLOW
]);
931 pctx
->u
.v1
.i_tei
= nla_get_u32(info
->attrs
[GTPA_I_TEI
]);
932 pctx
->u
.v1
.o_tei
= nla_get_u32(info
->attrs
[GTPA_O_TEI
]);
939 static int gtp_pdp_add(struct gtp_dev
*gtp
, struct sock
*sk
,
940 struct genl_info
*info
)
942 struct pdp_ctx
*pctx
, *pctx_tid
= NULL
;
943 struct net_device
*dev
= gtp
->dev
;
944 u32 hash_ms
, hash_tid
= 0;
945 unsigned int version
;
949 ms_addr
= nla_get_be32(info
->attrs
[GTPA_MS_ADDRESS
]);
950 hash_ms
= ipv4_hashfn(ms_addr
) % gtp
->hash_size
;
951 version
= nla_get_u32(info
->attrs
[GTPA_VERSION
]);
953 pctx
= ipv4_pdp_find(gtp
, ms_addr
);
956 if (version
== GTP_V0
)
957 pctx_tid
= gtp0_pdp_find(gtp
,
958 nla_get_u64(info
->attrs
[GTPA_TID
]));
959 else if (version
== GTP_V1
)
960 pctx_tid
= gtp1_pdp_find(gtp
,
961 nla_get_u32(info
->attrs
[GTPA_I_TEI
]));
966 if (info
->nlhdr
->nlmsg_flags
& NLM_F_EXCL
)
968 if (info
->nlhdr
->nlmsg_flags
& NLM_F_REPLACE
)
971 if (pctx
&& pctx_tid
)
976 ipv4_pdp_fill(pctx
, info
);
978 if (pctx
->gtp_version
== GTP_V0
)
979 netdev_dbg(dev
, "GTPv0-U: update tunnel id = %llx (pdp %p)\n",
980 pctx
->u
.v0
.tid
, pctx
);
981 else if (pctx
->gtp_version
== GTP_V1
)
982 netdev_dbg(dev
, "GTPv1-U: update tunnel id = %x/%x (pdp %p)\n",
983 pctx
->u
.v1
.i_tei
, pctx
->u
.v1
.o_tei
, pctx
);
989 pctx
= kmalloc(sizeof(*pctx
), GFP_ATOMIC
);
995 pctx
->dev
= gtp
->dev
;
996 ipv4_pdp_fill(pctx
, info
);
997 atomic_set(&pctx
->tx_seq
, 0);
999 switch (pctx
->gtp_version
) {
1001 /* TS 09.60: "The flow label identifies unambiguously a GTP
1002 * flow.". We use the tid for this instead, I cannot find a
1003 * situation in which this doesn't unambiguosly identify the
1006 hash_tid
= gtp0_hashfn(pctx
->u
.v0
.tid
) % gtp
->hash_size
;
1009 hash_tid
= gtp1u_hashfn(pctx
->u
.v1
.i_tei
) % gtp
->hash_size
;
1013 hlist_add_head_rcu(&pctx
->hlist_addr
, >p
->addr_hash
[hash_ms
]);
1014 hlist_add_head_rcu(&pctx
->hlist_tid
, >p
->tid_hash
[hash_tid
]);
1016 switch (pctx
->gtp_version
) {
1018 netdev_dbg(dev
, "GTPv0-U: new PDP ctx id=%llx ssgn=%pI4 ms=%pI4 (pdp=%p)\n",
1019 pctx
->u
.v0
.tid
, &pctx
->peer_addr_ip4
,
1020 &pctx
->ms_addr_ip4
, pctx
);
1023 netdev_dbg(dev
, "GTPv1-U: new PDP ctx id=%x/%x ssgn=%pI4 ms=%pI4 (pdp=%p)\n",
1024 pctx
->u
.v1
.i_tei
, pctx
->u
.v1
.o_tei
,
1025 &pctx
->peer_addr_ip4
, &pctx
->ms_addr_ip4
, pctx
);
1032 static void pdp_context_free(struct rcu_head
*head
)
1034 struct pdp_ctx
*pctx
= container_of(head
, struct pdp_ctx
, rcu_head
);
1040 static void pdp_context_delete(struct pdp_ctx
*pctx
)
1042 hlist_del_rcu(&pctx
->hlist_tid
);
1043 hlist_del_rcu(&pctx
->hlist_addr
);
1044 call_rcu(&pctx
->rcu_head
, pdp_context_free
);
1047 static int gtp_genl_new_pdp(struct sk_buff
*skb
, struct genl_info
*info
)
1049 unsigned int version
;
1050 struct gtp_dev
*gtp
;
1054 if (!info
->attrs
[GTPA_VERSION
] ||
1055 !info
->attrs
[GTPA_LINK
] ||
1056 !info
->attrs
[GTPA_PEER_ADDRESS
] ||
1057 !info
->attrs
[GTPA_MS_ADDRESS
])
1060 version
= nla_get_u32(info
->attrs
[GTPA_VERSION
]);
1064 if (!info
->attrs
[GTPA_TID
] ||
1065 !info
->attrs
[GTPA_FLOW
])
1069 if (!info
->attrs
[GTPA_I_TEI
] ||
1070 !info
->attrs
[GTPA_O_TEI
])
1081 gtp
= gtp_find_dev(sock_net(skb
->sk
), info
->attrs
);
1087 if (version
== GTP_V0
)
1089 else if (version
== GTP_V1
)
1099 err
= gtp_pdp_add(gtp
, sk
, info
);
1107 static struct pdp_ctx
*gtp_find_pdp_by_link(struct net
*net
,
1108 struct nlattr
*nla
[])
1110 struct gtp_dev
*gtp
;
1112 gtp
= gtp_find_dev(net
, nla
);
1114 return ERR_PTR(-ENODEV
);
1116 if (nla
[GTPA_MS_ADDRESS
]) {
1117 __be32 ip
= nla_get_be32(nla
[GTPA_MS_ADDRESS
]);
1119 return ipv4_pdp_find(gtp
, ip
);
1120 } else if (nla
[GTPA_VERSION
]) {
1121 u32 gtp_version
= nla_get_u32(nla
[GTPA_VERSION
]);
1123 if (gtp_version
== GTP_V0
&& nla
[GTPA_TID
])
1124 return gtp0_pdp_find(gtp
, nla_get_u64(nla
[GTPA_TID
]));
1125 else if (gtp_version
== GTP_V1
&& nla
[GTPA_I_TEI
])
1126 return gtp1_pdp_find(gtp
, nla_get_u32(nla
[GTPA_I_TEI
]));
1129 return ERR_PTR(-EINVAL
);
1132 static struct pdp_ctx
*gtp_find_pdp(struct net
*net
, struct nlattr
*nla
[])
1134 struct pdp_ctx
*pctx
;
1137 pctx
= gtp_find_pdp_by_link(net
, nla
);
1139 pctx
= ERR_PTR(-EINVAL
);
1142 pctx
= ERR_PTR(-ENOENT
);
1147 static int gtp_genl_del_pdp(struct sk_buff
*skb
, struct genl_info
*info
)
1149 struct pdp_ctx
*pctx
;
1152 if (!info
->attrs
[GTPA_VERSION
])
1157 pctx
= gtp_find_pdp(sock_net(skb
->sk
), info
->attrs
);
1159 err
= PTR_ERR(pctx
);
1163 if (pctx
->gtp_version
== GTP_V0
)
1164 netdev_dbg(pctx
->dev
, "GTPv0-U: deleting tunnel id = %llx (pdp %p)\n",
1165 pctx
->u
.v0
.tid
, pctx
);
1166 else if (pctx
->gtp_version
== GTP_V1
)
1167 netdev_dbg(pctx
->dev
, "GTPv1-U: deleting tunnel id = %x/%x (pdp %p)\n",
1168 pctx
->u
.v1
.i_tei
, pctx
->u
.v1
.o_tei
, pctx
);
1170 pdp_context_delete(pctx
);
1177 static struct genl_family gtp_genl_family
;
1179 static int gtp_genl_fill_info(struct sk_buff
*skb
, u32 snd_portid
, u32 snd_seq
,
1180 int flags
, u32 type
, struct pdp_ctx
*pctx
)
1184 genlh
= genlmsg_put(skb
, snd_portid
, snd_seq
, >p_genl_family
, flags
,
1189 if (nla_put_u32(skb
, GTPA_VERSION
, pctx
->gtp_version
) ||
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");