1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* GTP according to GSM TS 09.60 / 3GPP TS 29.060
4 * (C) 2012-2014 by sysmocom - s.f.m.c. GmbH
5 * (C) 2016 by Pablo Neira Ayuso <pablo@netfilter.org>
7 * Author: Harald Welte <hwelte@sysmocom.de>
8 * Pablo Neira Ayuso <pablo@netfilter.org>
9 * Andreas Schultz <aschultz@travelping.com>
12 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14 #include <linux/module.h>
15 #include <linux/skbuff.h>
16 #include <linux/udp.h>
17 #include <linux/rculist.h>
18 #include <linux/jhash.h>
19 #include <linux/if_tunnel.h>
20 #include <linux/net.h>
21 #include <linux/file.h>
22 #include <linux/gtp.h>
24 #include <net/net_namespace.h>
25 #include <net/protocol.h>
28 #include <net/udp_tunnel.h>
31 #include <net/genetlink.h>
32 #include <net/netns/generic.h>
35 /* An active session for the subscriber. */
37 struct hlist_node hlist_tid
;
38 struct hlist_node hlist_addr
;
53 struct in_addr ms_addr_ip4
;
54 struct in_addr peer_addr_ip4
;
57 struct net_device
*dev
;
60 struct rcu_head rcu_head
;
63 /* One instance of the GTP device. */
65 struct list_head list
;
70 struct net_device
*dev
;
73 unsigned int hash_size
;
74 struct hlist_head
*tid_hash
;
75 struct hlist_head
*addr_hash
;
78 static unsigned int gtp_net_id __read_mostly
;
81 struct list_head gtp_dev_list
;
84 static u32 gtp_h_initval
;
86 static void pdp_context_delete(struct pdp_ctx
*pctx
);
88 static inline u32
gtp0_hashfn(u64 tid
)
90 u32
*tid32
= (u32
*) &tid
;
91 return jhash_2words(tid32
[0], tid32
[1], gtp_h_initval
);
94 static inline u32
gtp1u_hashfn(u32 tid
)
96 return jhash_1word(tid
, gtp_h_initval
);
99 static inline u32
ipv4_hashfn(__be32 ip
)
101 return jhash_1word((__force u32
)ip
, gtp_h_initval
);
104 /* Resolve a PDP context structure based on the 64bit TID. */
105 static struct pdp_ctx
*gtp0_pdp_find(struct gtp_dev
*gtp
, u64 tid
)
107 struct hlist_head
*head
;
110 head
= >p
->tid_hash
[gtp0_hashfn(tid
) % gtp
->hash_size
];
112 hlist_for_each_entry_rcu(pdp
, head
, hlist_tid
) {
113 if (pdp
->gtp_version
== GTP_V0
&&
114 pdp
->u
.v0
.tid
== tid
)
120 /* Resolve a PDP context structure based on the 32bit TEI. */
121 static struct pdp_ctx
*gtp1_pdp_find(struct gtp_dev
*gtp
, u32 tid
)
123 struct hlist_head
*head
;
126 head
= >p
->tid_hash
[gtp1u_hashfn(tid
) % gtp
->hash_size
];
128 hlist_for_each_entry_rcu(pdp
, head
, hlist_tid
) {
129 if (pdp
->gtp_version
== GTP_V1
&&
130 pdp
->u
.v1
.i_tei
== tid
)
136 /* Resolve a PDP context based on IPv4 address of MS. */
137 static struct pdp_ctx
*ipv4_pdp_find(struct gtp_dev
*gtp
, __be32 ms_addr
)
139 struct hlist_head
*head
;
142 head
= >p
->addr_hash
[ipv4_hashfn(ms_addr
) % gtp
->hash_size
];
144 hlist_for_each_entry_rcu(pdp
, head
, hlist_addr
) {
145 if (pdp
->af
== AF_INET
&&
146 pdp
->ms_addr_ip4
.s_addr
== ms_addr
)
153 static bool gtp_check_ms_ipv4(struct sk_buff
*skb
, struct pdp_ctx
*pctx
,
154 unsigned int hdrlen
, unsigned int role
)
158 if (!pskb_may_pull(skb
, hdrlen
+ sizeof(struct iphdr
)))
161 iph
= (struct iphdr
*)(skb
->data
+ hdrlen
);
163 if (role
== GTP_ROLE_SGSN
)
164 return iph
->daddr
== pctx
->ms_addr_ip4
.s_addr
;
166 return iph
->saddr
== pctx
->ms_addr_ip4
.s_addr
;
169 /* Check if the inner IP address in this packet is assigned to any
170 * existing mobile subscriber.
172 static bool gtp_check_ms(struct sk_buff
*skb
, struct pdp_ctx
*pctx
,
173 unsigned int hdrlen
, unsigned int role
)
175 switch (ntohs(skb
->protocol
)) {
177 return gtp_check_ms_ipv4(skb
, pctx
, hdrlen
, role
);
182 static int gtp_rx(struct pdp_ctx
*pctx
, struct sk_buff
*skb
,
183 unsigned int hdrlen
, unsigned int role
)
185 struct pcpu_sw_netstats
*stats
;
187 if (!gtp_check_ms(skb
, pctx
, hdrlen
, role
)) {
188 netdev_dbg(pctx
->dev
, "No PDP ctx for this MS\n");
192 /* Get rid of the GTP + UDP headers. */
193 if (iptunnel_pull_header(skb
, hdrlen
, skb
->protocol
,
194 !net_eq(sock_net(pctx
->sk
), dev_net(pctx
->dev
))))
197 netdev_dbg(pctx
->dev
, "forwarding packet from GGSN to uplink\n");
199 /* Now that the UDP and the GTP header have been removed, set up the
200 * new network header. This is required by the upper layer to
201 * calculate the transport header.
203 skb_reset_network_header(skb
);
205 skb
->dev
= pctx
->dev
;
207 stats
= this_cpu_ptr(pctx
->dev
->tstats
);
208 u64_stats_update_begin(&stats
->syncp
);
210 stats
->rx_bytes
+= skb
->len
;
211 u64_stats_update_end(&stats
->syncp
);
217 /* 1 means pass up to the stack, -1 means drop and 0 means decapsulated. */
218 static int gtp0_udp_encap_recv(struct gtp_dev
*gtp
, struct sk_buff
*skb
)
220 unsigned int hdrlen
= sizeof(struct udphdr
) +
221 sizeof(struct gtp0_header
);
222 struct gtp0_header
*gtp0
;
223 struct pdp_ctx
*pctx
;
225 if (!pskb_may_pull(skb
, hdrlen
))
228 gtp0
= (struct gtp0_header
*)(skb
->data
+ sizeof(struct udphdr
));
230 if ((gtp0
->flags
>> 5) != GTP_V0
)
233 if (gtp0
->type
!= GTP_TPDU
)
236 pctx
= gtp0_pdp_find(gtp
, be64_to_cpu(gtp0
->tid
));
238 netdev_dbg(gtp
->dev
, "No PDP ctx to decap skb=%p\n", skb
);
242 return gtp_rx(pctx
, skb
, hdrlen
, gtp
->role
);
245 static int gtp1u_udp_encap_recv(struct gtp_dev
*gtp
, struct sk_buff
*skb
)
247 unsigned int hdrlen
= sizeof(struct udphdr
) +
248 sizeof(struct gtp1_header
);
249 struct gtp1_header
*gtp1
;
250 struct pdp_ctx
*pctx
;
252 if (!pskb_may_pull(skb
, hdrlen
))
255 gtp1
= (struct gtp1_header
*)(skb
->data
+ sizeof(struct udphdr
));
257 if ((gtp1
->flags
>> 5) != GTP_V1
)
260 if (gtp1
->type
!= GTP_TPDU
)
263 /* From 29.060: "This field shall be present if and only if any one or
264 * more of the S, PN and E flags are set.".
266 * If any of the bit is set, then the remaining ones also have to be
269 if (gtp1
->flags
& GTP1_F_MASK
)
272 /* Make sure the header is larger enough, including extensions. */
273 if (!pskb_may_pull(skb
, hdrlen
))
276 gtp1
= (struct gtp1_header
*)(skb
->data
+ sizeof(struct udphdr
));
278 pctx
= gtp1_pdp_find(gtp
, ntohl(gtp1
->tid
));
280 netdev_dbg(gtp
->dev
, "No PDP ctx to decap skb=%p\n", skb
);
284 return gtp_rx(pctx
, skb
, hdrlen
, gtp
->role
);
287 static void __gtp_encap_destroy(struct sock
*sk
)
292 gtp
= sk
->sk_user_data
;
298 udp_sk(sk
)->encap_type
= 0;
299 rcu_assign_sk_user_data(sk
, NULL
);
305 static void gtp_encap_destroy(struct sock
*sk
)
308 __gtp_encap_destroy(sk
);
312 static void gtp_encap_disable_sock(struct sock
*sk
)
317 __gtp_encap_destroy(sk
);
320 static void gtp_encap_disable(struct gtp_dev
*gtp
)
322 gtp_encap_disable_sock(gtp
->sk0
);
323 gtp_encap_disable_sock(gtp
->sk1u
);
326 /* UDP encapsulation receive handler. See net/ipv4/udp.c.
327 * Return codes: 0: success, <0: error, >0: pass up to userspace UDP socket.
329 static int gtp_encap_recv(struct sock
*sk
, struct sk_buff
*skb
)
334 gtp
= rcu_dereference_sk_user_data(sk
);
338 netdev_dbg(gtp
->dev
, "encap_recv sk=%p\n", sk
);
340 switch (udp_sk(sk
)->encap_type
) {
342 netdev_dbg(gtp
->dev
, "received GTP0 packet\n");
343 ret
= gtp0_udp_encap_recv(gtp
, skb
);
345 case UDP_ENCAP_GTP1U
:
346 netdev_dbg(gtp
->dev
, "received GTP1U packet\n");
347 ret
= gtp1u_udp_encap_recv(gtp
, skb
);
350 ret
= -1; /* Shouldn't happen. */
355 netdev_dbg(gtp
->dev
, "pass up to the process\n");
360 netdev_dbg(gtp
->dev
, "GTP packet has been dropped\n");
369 static int gtp_dev_init(struct net_device
*dev
)
371 struct gtp_dev
*gtp
= netdev_priv(dev
);
375 dev
->tstats
= netdev_alloc_pcpu_stats(struct pcpu_sw_netstats
);
382 static void gtp_dev_uninit(struct net_device
*dev
)
384 struct gtp_dev
*gtp
= netdev_priv(dev
);
386 gtp_encap_disable(gtp
);
387 free_percpu(dev
->tstats
);
390 static struct rtable
*ip4_route_output_gtp(struct flowi4
*fl4
,
391 const struct sock
*sk
,
394 memset(fl4
, 0, sizeof(*fl4
));
395 fl4
->flowi4_oif
= sk
->sk_bound_dev_if
;
397 fl4
->saddr
= inet_sk(sk
)->inet_saddr
;
398 fl4
->flowi4_tos
= RT_CONN_FLAGS(sk
);
399 fl4
->flowi4_proto
= sk
->sk_protocol
;
401 return ip_route_output_key(sock_net(sk
), fl4
);
404 static inline void gtp0_push_header(struct sk_buff
*skb
, struct pdp_ctx
*pctx
)
406 int payload_len
= skb
->len
;
407 struct gtp0_header
*gtp0
;
409 gtp0
= skb_push(skb
, sizeof(*gtp0
));
411 gtp0
->flags
= 0x1e; /* v0, GTP-non-prime. */
412 gtp0
->type
= GTP_TPDU
;
413 gtp0
->length
= htons(payload_len
);
414 gtp0
->seq
= htons((atomic_inc_return(&pctx
->tx_seq
) - 1) % 0xffff);
415 gtp0
->flow
= htons(pctx
->u
.v0
.flow
);
417 gtp0
->spare
[0] = gtp0
->spare
[1] = gtp0
->spare
[2] = 0xff;
418 gtp0
->tid
= cpu_to_be64(pctx
->u
.v0
.tid
);
421 static inline void gtp1_push_header(struct sk_buff
*skb
, struct pdp_ctx
*pctx
)
423 int payload_len
= skb
->len
;
424 struct gtp1_header
*gtp1
;
426 gtp1
= skb_push(skb
, sizeof(*gtp1
));
428 /* Bits 8 7 6 5 4 3 2 1
429 * +--+--+--+--+--+--+--+--+
430 * |version |PT| 0| E| S|PN|
431 * +--+--+--+--+--+--+--+--+
434 gtp1
->flags
= 0x30; /* v1, GTP-non-prime. */
435 gtp1
->type
= GTP_TPDU
;
436 gtp1
->length
= htons(payload_len
);
437 gtp1
->tid
= htonl(pctx
->u
.v1
.o_tei
);
439 /* TODO: Suppport for extension header, sequence number and N-PDU.
440 * Update the length field if any of them is available.
449 struct pdp_ctx
*pctx
;
450 struct net_device
*dev
;
454 static void gtp_push_header(struct sk_buff
*skb
, struct gtp_pktinfo
*pktinfo
)
456 switch (pktinfo
->pctx
->gtp_version
) {
458 pktinfo
->gtph_port
= htons(GTP0_PORT
);
459 gtp0_push_header(skb
, pktinfo
->pctx
);
462 pktinfo
->gtph_port
= htons(GTP1U_PORT
);
463 gtp1_push_header(skb
, pktinfo
->pctx
);
468 static inline void gtp_set_pktinfo_ipv4(struct gtp_pktinfo
*pktinfo
,
469 struct sock
*sk
, struct iphdr
*iph
,
470 struct pdp_ctx
*pctx
, struct rtable
*rt
,
472 struct net_device
*dev
)
476 pktinfo
->pctx
= pctx
;
482 static int gtp_build_skb_ip4(struct sk_buff
*skb
, struct net_device
*dev
,
483 struct gtp_pktinfo
*pktinfo
)
485 struct gtp_dev
*gtp
= netdev_priv(dev
);
486 struct pdp_ctx
*pctx
;
493 /* Read the IP destination address and resolve the PDP context.
494 * Prepend PDP header with TEI/TID from PDP ctx.
497 if (gtp
->role
== GTP_ROLE_SGSN
)
498 pctx
= ipv4_pdp_find(gtp
, iph
->saddr
);
500 pctx
= ipv4_pdp_find(gtp
, iph
->daddr
);
503 netdev_dbg(dev
, "no PDP ctx found for %pI4, skip\n",
507 netdev_dbg(dev
, "found PDP context %p\n", pctx
);
509 rt
= ip4_route_output_gtp(&fl4
, pctx
->sk
, pctx
->peer_addr_ip4
.s_addr
);
511 netdev_dbg(dev
, "no route to SSGN %pI4\n",
512 &pctx
->peer_addr_ip4
.s_addr
);
513 dev
->stats
.tx_carrier_errors
++;
517 if (rt
->dst
.dev
== dev
) {
518 netdev_dbg(dev
, "circular route to SSGN %pI4\n",
519 &pctx
->peer_addr_ip4
.s_addr
);
520 dev
->stats
.collisions
++;
526 /* This is similar to tnl_update_pmtu(). */
529 mtu
= dst_mtu(&rt
->dst
) - dev
->hard_header_len
-
530 sizeof(struct iphdr
) - sizeof(struct udphdr
);
531 switch (pctx
->gtp_version
) {
533 mtu
-= sizeof(struct gtp0_header
);
536 mtu
-= sizeof(struct gtp1_header
);
540 mtu
= dst_mtu(&rt
->dst
);
543 rt
->dst
.ops
->update_pmtu(&rt
->dst
, NULL
, skb
, mtu
, false);
545 if (!skb_is_gso(skb
) && (iph
->frag_off
& htons(IP_DF
)) &&
546 mtu
< ntohs(iph
->tot_len
)) {
547 netdev_dbg(dev
, "packet too big, fragmentation needed\n");
548 memset(IPCB(skb
), 0, sizeof(*IPCB(skb
)));
549 icmp_send(skb
, ICMP_DEST_UNREACH
, ICMP_FRAG_NEEDED
,
554 gtp_set_pktinfo_ipv4(pktinfo
, pctx
->sk
, iph
, pctx
, rt
, &fl4
, dev
);
555 gtp_push_header(skb
, pktinfo
);
564 static netdev_tx_t
gtp_dev_xmit(struct sk_buff
*skb
, struct net_device
*dev
)
566 unsigned int proto
= ntohs(skb
->protocol
);
567 struct gtp_pktinfo pktinfo
;
570 /* Ensure there is sufficient headroom. */
571 if (skb_cow_head(skb
, dev
->needed_headroom
))
574 skb_reset_inner_headers(skb
);
576 /* PDP context lookups in gtp_build_skb_*() need rcu read-side lock. */
580 err
= gtp_build_skb_ip4(skb
, dev
, &pktinfo
);
593 netdev_dbg(pktinfo
.dev
, "gtp -> IP src: %pI4 dst: %pI4\n",
594 &pktinfo
.iph
->saddr
, &pktinfo
.iph
->daddr
);
595 udp_tunnel_xmit_skb(pktinfo
.rt
, pktinfo
.sk
, skb
,
596 pktinfo
.fl4
.saddr
, pktinfo
.fl4
.daddr
,
598 ip4_dst_hoplimit(&pktinfo
.rt
->dst
),
600 pktinfo
.gtph_port
, pktinfo
.gtph_port
,
607 dev
->stats
.tx_errors
++;
612 static const struct net_device_ops gtp_netdev_ops
= {
613 .ndo_init
= gtp_dev_init
,
614 .ndo_uninit
= gtp_dev_uninit
,
615 .ndo_start_xmit
= gtp_dev_xmit
,
616 .ndo_get_stats64
= ip_tunnel_get_stats64
,
619 static void gtp_link_setup(struct net_device
*dev
)
621 dev
->netdev_ops
= >p_netdev_ops
;
622 dev
->needs_free_netdev
= true;
624 dev
->hard_header_len
= 0;
627 /* Zero header length. */
628 dev
->type
= ARPHRD_NONE
;
629 dev
->flags
= IFF_POINTOPOINT
| IFF_NOARP
| IFF_MULTICAST
;
631 dev
->priv_flags
|= IFF_NO_QUEUE
;
632 dev
->features
|= NETIF_F_LLTX
;
635 /* Assume largest header, ie. GTPv0. */
636 dev
->needed_headroom
= LL_MAX_HEADER
+
637 sizeof(struct iphdr
) +
638 sizeof(struct udphdr
) +
639 sizeof(struct gtp0_header
);
642 static int gtp_hashtable_new(struct gtp_dev
*gtp
, int hsize
);
643 static int gtp_encap_enable(struct gtp_dev
*gtp
, struct nlattr
*data
[]);
645 static void gtp_destructor(struct net_device
*dev
)
647 struct gtp_dev
*gtp
= netdev_priv(dev
);
649 kfree(gtp
->addr_hash
);
650 kfree(gtp
->tid_hash
);
653 static int gtp_newlink(struct net
*src_net
, struct net_device
*dev
,
654 struct nlattr
*tb
[], struct nlattr
*data
[],
655 struct netlink_ext_ack
*extack
)
661 if (!data
[IFLA_GTP_FD0
] && !data
[IFLA_GTP_FD1
])
664 gtp
= netdev_priv(dev
);
666 err
= gtp_encap_enable(gtp
, data
);
670 if (!data
[IFLA_GTP_PDP_HASHSIZE
]) {
673 hashsize
= nla_get_u32(data
[IFLA_GTP_PDP_HASHSIZE
]);
678 err
= gtp_hashtable_new(gtp
, hashsize
);
682 err
= register_netdevice(dev
);
684 netdev_dbg(dev
, "failed to register new netdev %d\n", err
);
688 gn
= net_generic(dev_net(dev
), gtp_net_id
);
689 list_add_rcu(>p
->list
, &gn
->gtp_dev_list
);
690 dev
->priv_destructor
= gtp_destructor
;
692 netdev_dbg(dev
, "registered new GTP interface\n");
697 kfree(gtp
->addr_hash
);
698 kfree(gtp
->tid_hash
);
700 gtp_encap_disable(gtp
);
704 static void gtp_dellink(struct net_device
*dev
, struct list_head
*head
)
706 struct gtp_dev
*gtp
= netdev_priv(dev
);
707 struct pdp_ctx
*pctx
;
710 for (i
= 0; i
< gtp
->hash_size
; i
++)
711 hlist_for_each_entry_rcu(pctx
, >p
->tid_hash
[i
], hlist_tid
)
712 pdp_context_delete(pctx
);
714 list_del_rcu(>p
->list
);
715 unregister_netdevice_queue(dev
, head
);
718 static const struct nla_policy gtp_policy
[IFLA_GTP_MAX
+ 1] = {
719 [IFLA_GTP_FD0
] = { .type
= NLA_U32
},
720 [IFLA_GTP_FD1
] = { .type
= NLA_U32
},
721 [IFLA_GTP_PDP_HASHSIZE
] = { .type
= NLA_U32
},
722 [IFLA_GTP_ROLE
] = { .type
= NLA_U32
},
725 static int gtp_validate(struct nlattr
*tb
[], struct nlattr
*data
[],
726 struct netlink_ext_ack
*extack
)
734 static size_t gtp_get_size(const struct net_device
*dev
)
736 return nla_total_size(sizeof(__u32
)); /* IFLA_GTP_PDP_HASHSIZE */
739 static int gtp_fill_info(struct sk_buff
*skb
, const struct net_device
*dev
)
741 struct gtp_dev
*gtp
= netdev_priv(dev
);
743 if (nla_put_u32(skb
, IFLA_GTP_PDP_HASHSIZE
, gtp
->hash_size
))
744 goto nla_put_failure
;
752 static struct rtnl_link_ops gtp_link_ops __read_mostly
= {
754 .maxtype
= IFLA_GTP_MAX
,
755 .policy
= gtp_policy
,
756 .priv_size
= sizeof(struct gtp_dev
),
757 .setup
= gtp_link_setup
,
758 .validate
= gtp_validate
,
759 .newlink
= gtp_newlink
,
760 .dellink
= gtp_dellink
,
761 .get_size
= gtp_get_size
,
762 .fill_info
= gtp_fill_info
,
765 static int gtp_hashtable_new(struct gtp_dev
*gtp
, int hsize
)
769 gtp
->addr_hash
= kmalloc_array(hsize
, sizeof(struct hlist_head
),
770 GFP_KERNEL
| __GFP_NOWARN
);
771 if (gtp
->addr_hash
== NULL
)
774 gtp
->tid_hash
= kmalloc_array(hsize
, sizeof(struct hlist_head
),
775 GFP_KERNEL
| __GFP_NOWARN
);
776 if (gtp
->tid_hash
== NULL
)
779 gtp
->hash_size
= hsize
;
781 for (i
= 0; i
< hsize
; i
++) {
782 INIT_HLIST_HEAD(>p
->addr_hash
[i
]);
783 INIT_HLIST_HEAD(>p
->tid_hash
[i
]);
787 kfree(gtp
->addr_hash
);
791 static struct sock
*gtp_encap_enable_socket(int fd
, int type
,
794 struct udp_tunnel_sock_cfg tuncfg
= {NULL
};
799 pr_debug("enable gtp on %d, %d\n", fd
, type
);
801 sock
= sockfd_lookup(fd
, &err
);
803 pr_debug("gtp socket fd=%d not found\n", fd
);
808 if (sk
->sk_protocol
!= IPPROTO_UDP
||
809 sk
->sk_type
!= SOCK_DGRAM
||
810 (sk
->sk_family
!= AF_INET
&& sk
->sk_family
!= AF_INET6
)) {
811 pr_debug("socket fd=%d not UDP\n", fd
);
812 sk
= ERR_PTR(-EINVAL
);
817 if (sk
->sk_user_data
) {
818 sk
= ERR_PTR(-EBUSY
);
824 tuncfg
.sk_user_data
= gtp
;
825 tuncfg
.encap_type
= type
;
826 tuncfg
.encap_rcv
= gtp_encap_recv
;
827 tuncfg
.encap_destroy
= gtp_encap_destroy
;
829 setup_udp_tunnel_sock(sock_net(sock
->sk
), sock
, &tuncfg
);
832 release_sock(sock
->sk
);
838 static int gtp_encap_enable(struct gtp_dev
*gtp
, struct nlattr
*data
[])
840 struct sock
*sk1u
= NULL
;
841 struct sock
*sk0
= NULL
;
842 unsigned int role
= GTP_ROLE_GGSN
;
844 if (data
[IFLA_GTP_FD0
]) {
845 u32 fd0
= nla_get_u32(data
[IFLA_GTP_FD0
]);
847 sk0
= gtp_encap_enable_socket(fd0
, UDP_ENCAP_GTP0
, gtp
);
852 if (data
[IFLA_GTP_FD1
]) {
853 u32 fd1
= nla_get_u32(data
[IFLA_GTP_FD1
]);
855 sk1u
= gtp_encap_enable_socket(fd1
, UDP_ENCAP_GTP1U
, gtp
);
857 gtp_encap_disable_sock(sk0
);
858 return PTR_ERR(sk1u
);
862 if (data
[IFLA_GTP_ROLE
]) {
863 role
= nla_get_u32(data
[IFLA_GTP_ROLE
]);
864 if (role
> GTP_ROLE_SGSN
) {
865 gtp_encap_disable_sock(sk0
);
866 gtp_encap_disable_sock(sk1u
);
878 static struct gtp_dev
*gtp_find_dev(struct net
*src_net
, struct nlattr
*nla
[])
880 struct gtp_dev
*gtp
= NULL
;
881 struct net_device
*dev
;
884 /* Examine the link attributes and figure out which network namespace
885 * we are talking about.
887 if (nla
[GTPA_NET_NS_FD
])
888 net
= get_net_ns_by_fd(nla_get_u32(nla
[GTPA_NET_NS_FD
]));
890 net
= get_net(src_net
);
895 /* Check if there's an existing gtpX device to configure */
896 dev
= dev_get_by_index_rcu(net
, nla_get_u32(nla
[GTPA_LINK
]));
897 if (dev
&& dev
->netdev_ops
== >p_netdev_ops
)
898 gtp
= netdev_priv(dev
);
904 static void ipv4_pdp_fill(struct pdp_ctx
*pctx
, struct genl_info
*info
)
906 pctx
->gtp_version
= nla_get_u32(info
->attrs
[GTPA_VERSION
]);
908 pctx
->peer_addr_ip4
.s_addr
=
909 nla_get_be32(info
->attrs
[GTPA_PEER_ADDRESS
]);
910 pctx
->ms_addr_ip4
.s_addr
=
911 nla_get_be32(info
->attrs
[GTPA_MS_ADDRESS
]);
913 switch (pctx
->gtp_version
) {
915 /* According to TS 09.60, sections 7.5.1 and 7.5.2, the flow
916 * label needs to be the same for uplink and downlink packets,
917 * so let's annotate this.
919 pctx
->u
.v0
.tid
= nla_get_u64(info
->attrs
[GTPA_TID
]);
920 pctx
->u
.v0
.flow
= nla_get_u16(info
->attrs
[GTPA_FLOW
]);
923 pctx
->u
.v1
.i_tei
= nla_get_u32(info
->attrs
[GTPA_I_TEI
]);
924 pctx
->u
.v1
.o_tei
= nla_get_u32(info
->attrs
[GTPA_O_TEI
]);
931 static int gtp_pdp_add(struct gtp_dev
*gtp
, struct sock
*sk
,
932 struct genl_info
*info
)
934 struct pdp_ctx
*pctx
, *pctx_tid
= NULL
;
935 struct net_device
*dev
= gtp
->dev
;
936 u32 hash_ms
, hash_tid
= 0;
937 unsigned int version
;
941 ms_addr
= nla_get_be32(info
->attrs
[GTPA_MS_ADDRESS
]);
942 hash_ms
= ipv4_hashfn(ms_addr
) % gtp
->hash_size
;
943 version
= nla_get_u32(info
->attrs
[GTPA_VERSION
]);
945 pctx
= ipv4_pdp_find(gtp
, ms_addr
);
948 if (version
== GTP_V0
)
949 pctx_tid
= gtp0_pdp_find(gtp
,
950 nla_get_u64(info
->attrs
[GTPA_TID
]));
951 else if (version
== GTP_V1
)
952 pctx_tid
= gtp1_pdp_find(gtp
,
953 nla_get_u32(info
->attrs
[GTPA_I_TEI
]));
958 if (info
->nlhdr
->nlmsg_flags
& NLM_F_EXCL
)
960 if (info
->nlhdr
->nlmsg_flags
& NLM_F_REPLACE
)
963 if (pctx
&& pctx_tid
)
968 ipv4_pdp_fill(pctx
, info
);
970 if (pctx
->gtp_version
== GTP_V0
)
971 netdev_dbg(dev
, "GTPv0-U: update tunnel id = %llx (pdp %p)\n",
972 pctx
->u
.v0
.tid
, pctx
);
973 else if (pctx
->gtp_version
== GTP_V1
)
974 netdev_dbg(dev
, "GTPv1-U: update tunnel id = %x/%x (pdp %p)\n",
975 pctx
->u
.v1
.i_tei
, pctx
->u
.v1
.o_tei
, pctx
);
981 pctx
= kmalloc(sizeof(*pctx
), GFP_ATOMIC
);
987 pctx
->dev
= gtp
->dev
;
988 ipv4_pdp_fill(pctx
, info
);
989 atomic_set(&pctx
->tx_seq
, 0);
991 switch (pctx
->gtp_version
) {
993 /* TS 09.60: "The flow label identifies unambiguously a GTP
994 * flow.". We use the tid for this instead, I cannot find a
995 * situation in which this doesn't unambiguosly identify the
998 hash_tid
= gtp0_hashfn(pctx
->u
.v0
.tid
) % gtp
->hash_size
;
1001 hash_tid
= gtp1u_hashfn(pctx
->u
.v1
.i_tei
) % gtp
->hash_size
;
1005 hlist_add_head_rcu(&pctx
->hlist_addr
, >p
->addr_hash
[hash_ms
]);
1006 hlist_add_head_rcu(&pctx
->hlist_tid
, >p
->tid_hash
[hash_tid
]);
1008 switch (pctx
->gtp_version
) {
1010 netdev_dbg(dev
, "GTPv0-U: new PDP ctx id=%llx ssgn=%pI4 ms=%pI4 (pdp=%p)\n",
1011 pctx
->u
.v0
.tid
, &pctx
->peer_addr_ip4
,
1012 &pctx
->ms_addr_ip4
, pctx
);
1015 netdev_dbg(dev
, "GTPv1-U: new PDP ctx id=%x/%x ssgn=%pI4 ms=%pI4 (pdp=%p)\n",
1016 pctx
->u
.v1
.i_tei
, pctx
->u
.v1
.o_tei
,
1017 &pctx
->peer_addr_ip4
, &pctx
->ms_addr_ip4
, pctx
);
1024 static void pdp_context_free(struct rcu_head
*head
)
1026 struct pdp_ctx
*pctx
= container_of(head
, struct pdp_ctx
, rcu_head
);
1032 static void pdp_context_delete(struct pdp_ctx
*pctx
)
1034 hlist_del_rcu(&pctx
->hlist_tid
);
1035 hlist_del_rcu(&pctx
->hlist_addr
);
1036 call_rcu(&pctx
->rcu_head
, pdp_context_free
);
1039 static int gtp_genl_new_pdp(struct sk_buff
*skb
, struct genl_info
*info
)
1041 unsigned int version
;
1042 struct gtp_dev
*gtp
;
1046 if (!info
->attrs
[GTPA_VERSION
] ||
1047 !info
->attrs
[GTPA_LINK
] ||
1048 !info
->attrs
[GTPA_PEER_ADDRESS
] ||
1049 !info
->attrs
[GTPA_MS_ADDRESS
])
1052 version
= nla_get_u32(info
->attrs
[GTPA_VERSION
]);
1056 if (!info
->attrs
[GTPA_TID
] ||
1057 !info
->attrs
[GTPA_FLOW
])
1061 if (!info
->attrs
[GTPA_I_TEI
] ||
1062 !info
->attrs
[GTPA_O_TEI
])
1073 gtp
= gtp_find_dev(sock_net(skb
->sk
), info
->attrs
);
1079 if (version
== GTP_V0
)
1081 else if (version
== GTP_V1
)
1091 err
= gtp_pdp_add(gtp
, sk
, info
);
1099 static struct pdp_ctx
*gtp_find_pdp_by_link(struct net
*net
,
1100 struct nlattr
*nla
[])
1102 struct gtp_dev
*gtp
;
1104 gtp
= gtp_find_dev(net
, nla
);
1106 return ERR_PTR(-ENODEV
);
1108 if (nla
[GTPA_MS_ADDRESS
]) {
1109 __be32 ip
= nla_get_be32(nla
[GTPA_MS_ADDRESS
]);
1111 return ipv4_pdp_find(gtp
, ip
);
1112 } else if (nla
[GTPA_VERSION
]) {
1113 u32 gtp_version
= nla_get_u32(nla
[GTPA_VERSION
]);
1115 if (gtp_version
== GTP_V0
&& nla
[GTPA_TID
])
1116 return gtp0_pdp_find(gtp
, nla_get_u64(nla
[GTPA_TID
]));
1117 else if (gtp_version
== GTP_V1
&& nla
[GTPA_I_TEI
])
1118 return gtp1_pdp_find(gtp
, nla_get_u32(nla
[GTPA_I_TEI
]));
1121 return ERR_PTR(-EINVAL
);
1124 static struct pdp_ctx
*gtp_find_pdp(struct net
*net
, struct nlattr
*nla
[])
1126 struct pdp_ctx
*pctx
;
1129 pctx
= gtp_find_pdp_by_link(net
, nla
);
1131 pctx
= ERR_PTR(-EINVAL
);
1134 pctx
= ERR_PTR(-ENOENT
);
1139 static int gtp_genl_del_pdp(struct sk_buff
*skb
, struct genl_info
*info
)
1141 struct pdp_ctx
*pctx
;
1144 if (!info
->attrs
[GTPA_VERSION
])
1149 pctx
= gtp_find_pdp(sock_net(skb
->sk
), info
->attrs
);
1151 err
= PTR_ERR(pctx
);
1155 if (pctx
->gtp_version
== GTP_V0
)
1156 netdev_dbg(pctx
->dev
, "GTPv0-U: deleting tunnel id = %llx (pdp %p)\n",
1157 pctx
->u
.v0
.tid
, pctx
);
1158 else if (pctx
->gtp_version
== GTP_V1
)
1159 netdev_dbg(pctx
->dev
, "GTPv1-U: deleting tunnel id = %x/%x (pdp %p)\n",
1160 pctx
->u
.v1
.i_tei
, pctx
->u
.v1
.o_tei
, pctx
);
1162 pdp_context_delete(pctx
);
1169 static struct genl_family gtp_genl_family
;
1171 static int gtp_genl_fill_info(struct sk_buff
*skb
, u32 snd_portid
, u32 snd_seq
,
1172 u32 type
, struct pdp_ctx
*pctx
)
1176 genlh
= genlmsg_put(skb
, snd_portid
, snd_seq
, >p_genl_family
, 0,
1181 if (nla_put_u32(skb
, GTPA_VERSION
, pctx
->gtp_version
) ||
1182 nla_put_be32(skb
, GTPA_PEER_ADDRESS
, pctx
->peer_addr_ip4
.s_addr
) ||
1183 nla_put_be32(skb
, GTPA_MS_ADDRESS
, pctx
->ms_addr_ip4
.s_addr
))
1184 goto nla_put_failure
;
1186 switch (pctx
->gtp_version
) {
1188 if (nla_put_u64_64bit(skb
, GTPA_TID
, pctx
->u
.v0
.tid
, GTPA_PAD
) ||
1189 nla_put_u16(skb
, GTPA_FLOW
, pctx
->u
.v0
.flow
))
1190 goto nla_put_failure
;
1193 if (nla_put_u32(skb
, GTPA_I_TEI
, pctx
->u
.v1
.i_tei
) ||
1194 nla_put_u32(skb
, GTPA_O_TEI
, pctx
->u
.v1
.o_tei
))
1195 goto nla_put_failure
;
1198 genlmsg_end(skb
, genlh
);
1203 genlmsg_cancel(skb
, genlh
);
1207 static int gtp_genl_get_pdp(struct sk_buff
*skb
, struct genl_info
*info
)
1209 struct pdp_ctx
*pctx
= NULL
;
1210 struct sk_buff
*skb2
;
1213 if (!info
->attrs
[GTPA_VERSION
])
1218 pctx
= gtp_find_pdp(sock_net(skb
->sk
), info
->attrs
);
1220 err
= PTR_ERR(pctx
);
1224 skb2
= genlmsg_new(NLMSG_GOODSIZE
, GFP_ATOMIC
);
1230 err
= gtp_genl_fill_info(skb2
, NETLINK_CB(skb
).portid
,
1231 info
->snd_seq
, info
->nlhdr
->nlmsg_type
, pctx
);
1233 goto err_unlock_free
;
1236 return genlmsg_unicast(genl_info_net(info
), skb2
, info
->snd_portid
);
1245 static int gtp_genl_dump_pdp(struct sk_buff
*skb
,
1246 struct netlink_callback
*cb
)
1248 struct gtp_dev
*last_gtp
= (struct gtp_dev
*)cb
->args
[2], *gtp
;
1249 int i
, j
, bucket
= cb
->args
[0], skip
= cb
->args
[1];
1250 struct net
*net
= sock_net(skb
->sk
);
1251 struct pdp_ctx
*pctx
;
1254 gn
= net_generic(net
, gtp_net_id
);
1260 list_for_each_entry_rcu(gtp
, &gn
->gtp_dev_list
, list
) {
1261 if (last_gtp
&& last_gtp
!= gtp
)
1266 for (i
= bucket
; i
< gtp
->hash_size
; i
++) {
1268 hlist_for_each_entry_rcu(pctx
, >p
->tid_hash
[i
],
1271 gtp_genl_fill_info(skb
,
1272 NETLINK_CB(cb
->skb
).portid
,
1274 cb
->nlh
->nlmsg_type
, pctx
)) {
1277 cb
->args
[2] = (unsigned long)gtp
;
1292 static const struct nla_policy gtp_genl_policy
[GTPA_MAX
+ 1] = {
1293 [GTPA_LINK
] = { .type
= NLA_U32
, },
1294 [GTPA_VERSION
] = { .type
= NLA_U32
, },
1295 [GTPA_TID
] = { .type
= NLA_U64
, },
1296 [GTPA_PEER_ADDRESS
] = { .type
= NLA_U32
, },
1297 [GTPA_MS_ADDRESS
] = { .type
= NLA_U32
, },
1298 [GTPA_FLOW
] = { .type
= NLA_U16
, },
1299 [GTPA_NET_NS_FD
] = { .type
= NLA_U32
, },
1300 [GTPA_I_TEI
] = { .type
= NLA_U32
, },
1301 [GTPA_O_TEI
] = { .type
= NLA_U32
, },
1304 static const struct genl_ops gtp_genl_ops
[] = {
1306 .cmd
= GTP_CMD_NEWPDP
,
1307 .validate
= GENL_DONT_VALIDATE_STRICT
| GENL_DONT_VALIDATE_DUMP
,
1308 .doit
= gtp_genl_new_pdp
,
1309 .flags
= GENL_ADMIN_PERM
,
1312 .cmd
= GTP_CMD_DELPDP
,
1313 .validate
= GENL_DONT_VALIDATE_STRICT
| GENL_DONT_VALIDATE_DUMP
,
1314 .doit
= gtp_genl_del_pdp
,
1315 .flags
= GENL_ADMIN_PERM
,
1318 .cmd
= GTP_CMD_GETPDP
,
1319 .validate
= GENL_DONT_VALIDATE_STRICT
| GENL_DONT_VALIDATE_DUMP
,
1320 .doit
= gtp_genl_get_pdp
,
1321 .dumpit
= gtp_genl_dump_pdp
,
1322 .flags
= GENL_ADMIN_PERM
,
1326 static struct genl_family gtp_genl_family __ro_after_init
= {
1330 .maxattr
= GTPA_MAX
,
1331 .policy
= gtp_genl_policy
,
1333 .module
= THIS_MODULE
,
1334 .ops
= gtp_genl_ops
,
1335 .n_ops
= ARRAY_SIZE(gtp_genl_ops
),
1338 static int __net_init
gtp_net_init(struct net
*net
)
1340 struct gtp_net
*gn
= net_generic(net
, gtp_net_id
);
1342 INIT_LIST_HEAD(&gn
->gtp_dev_list
);
1346 static void __net_exit
gtp_net_exit(struct net
*net
)
1348 struct gtp_net
*gn
= net_generic(net
, gtp_net_id
);
1349 struct gtp_dev
*gtp
;
1353 list_for_each_entry(gtp
, &gn
->gtp_dev_list
, list
)
1354 gtp_dellink(gtp
->dev
, &list
);
1356 unregister_netdevice_many(&list
);
1360 static struct pernet_operations gtp_net_ops
= {
1361 .init
= gtp_net_init
,
1362 .exit
= gtp_net_exit
,
1364 .size
= sizeof(struct gtp_net
),
1367 static int __init
gtp_init(void)
1371 get_random_bytes(>p_h_initval
, sizeof(gtp_h_initval
));
1373 err
= rtnl_link_register(>p_link_ops
);
1377 err
= genl_register_family(>p_genl_family
);
1379 goto unreg_rtnl_link
;
1381 err
= register_pernet_subsys(>p_net_ops
);
1383 goto unreg_genl_family
;
1385 pr_info("GTP module loaded (pdp ctx size %zd bytes)\n",
1386 sizeof(struct pdp_ctx
));
1390 genl_unregister_family(>p_genl_family
);
1392 rtnl_link_unregister(>p_link_ops
);
1394 pr_err("error loading GTP module loaded\n");
1397 late_initcall(gtp_init
);
1399 static void __exit
gtp_fini(void)
1401 genl_unregister_family(>p_genl_family
);
1402 rtnl_link_unregister(>p_link_ops
);
1403 unregister_pernet_subsys(>p_net_ops
);
1405 pr_info("GTP module unloaded\n");
1407 module_exit(gtp_fini
);
1409 MODULE_LICENSE("GPL");
1410 MODULE_AUTHOR("Harald Welte <hwelte@sysmocom.de>");
1411 MODULE_DESCRIPTION("Interface driver for GTP encapsulated traffic");
1412 MODULE_ALIAS_RTNL_LINK("gtp");
1413 MODULE_ALIAS_GENL_FAMILY("gtp");