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
;
58 struct in_addr ms_addr_ip4
;
59 struct in_addr peer_addr_ip4
;
62 struct net_device
*dev
;
65 struct rcu_head rcu_head
;
68 /* One instance of the GTP device. */
70 struct list_head list
;
75 struct net_device
*dev
;
78 unsigned int hash_size
;
79 struct hlist_head
*tid_hash
;
80 struct hlist_head
*addr_hash
;
83 static unsigned int gtp_net_id __read_mostly
;
86 struct list_head gtp_dev_list
;
89 static u32 gtp_h_initval
;
91 static void pdp_context_delete(struct pdp_ctx
*pctx
);
93 static inline u32
gtp0_hashfn(u64 tid
)
95 u32
*tid32
= (u32
*) &tid
;
96 return jhash_2words(tid32
[0], tid32
[1], gtp_h_initval
);
99 static inline u32
gtp1u_hashfn(u32 tid
)
101 return jhash_1word(tid
, gtp_h_initval
);
104 static inline u32
ipv4_hashfn(__be32 ip
)
106 return jhash_1word((__force u32
)ip
, gtp_h_initval
);
109 /* Resolve a PDP context structure based on the 64bit TID. */
110 static struct pdp_ctx
*gtp0_pdp_find(struct gtp_dev
*gtp
, u64 tid
)
112 struct hlist_head
*head
;
115 head
= >p
->tid_hash
[gtp0_hashfn(tid
) % gtp
->hash_size
];
117 hlist_for_each_entry_rcu(pdp
, head
, hlist_tid
) {
118 if (pdp
->gtp_version
== GTP_V0
&&
119 pdp
->u
.v0
.tid
== tid
)
125 /* Resolve a PDP context structure based on the 32bit TEI. */
126 static struct pdp_ctx
*gtp1_pdp_find(struct gtp_dev
*gtp
, u32 tid
)
128 struct hlist_head
*head
;
131 head
= >p
->tid_hash
[gtp1u_hashfn(tid
) % gtp
->hash_size
];
133 hlist_for_each_entry_rcu(pdp
, head
, hlist_tid
) {
134 if (pdp
->gtp_version
== GTP_V1
&&
135 pdp
->u
.v1
.i_tei
== tid
)
141 /* Resolve a PDP context based on IPv4 address of MS. */
142 static struct pdp_ctx
*ipv4_pdp_find(struct gtp_dev
*gtp
, __be32 ms_addr
)
144 struct hlist_head
*head
;
147 head
= >p
->addr_hash
[ipv4_hashfn(ms_addr
) % gtp
->hash_size
];
149 hlist_for_each_entry_rcu(pdp
, head
, hlist_addr
) {
150 if (pdp
->af
== AF_INET
&&
151 pdp
->ms_addr_ip4
.s_addr
== ms_addr
)
158 static bool gtp_check_ms_ipv4(struct sk_buff
*skb
, struct pdp_ctx
*pctx
,
159 unsigned int hdrlen
, unsigned int role
)
163 if (!pskb_may_pull(skb
, hdrlen
+ sizeof(struct iphdr
)))
166 iph
= (struct iphdr
*)(skb
->data
+ hdrlen
);
168 if (role
== GTP_ROLE_SGSN
)
169 return iph
->daddr
== pctx
->ms_addr_ip4
.s_addr
;
171 return iph
->saddr
== pctx
->ms_addr_ip4
.s_addr
;
174 /* Check if the inner IP address in this packet is assigned to any
175 * existing mobile subscriber.
177 static bool gtp_check_ms(struct sk_buff
*skb
, struct pdp_ctx
*pctx
,
178 unsigned int hdrlen
, unsigned int role
)
180 switch (ntohs(skb
->protocol
)) {
182 return gtp_check_ms_ipv4(skb
, pctx
, hdrlen
, role
);
187 static int gtp_rx(struct pdp_ctx
*pctx
, struct sk_buff
*skb
,
188 unsigned int hdrlen
, unsigned int role
)
190 struct pcpu_sw_netstats
*stats
;
192 if (!gtp_check_ms(skb
, pctx
, hdrlen
, role
)) {
193 netdev_dbg(pctx
->dev
, "No PDP ctx for this MS\n");
197 /* Get rid of the GTP + UDP headers. */
198 if (iptunnel_pull_header(skb
, hdrlen
, skb
->protocol
,
199 !net_eq(sock_net(pctx
->sk
), dev_net(pctx
->dev
))))
202 netdev_dbg(pctx
->dev
, "forwarding packet from GGSN to uplink\n");
204 /* Now that the UDP and the GTP header have been removed, set up the
205 * new network header. This is required by the upper layer to
206 * calculate the transport header.
208 skb_reset_network_header(skb
);
210 skb
->dev
= pctx
->dev
;
212 stats
= this_cpu_ptr(pctx
->dev
->tstats
);
213 u64_stats_update_begin(&stats
->syncp
);
215 stats
->rx_bytes
+= skb
->len
;
216 u64_stats_update_end(&stats
->syncp
);
222 /* 1 means pass up to the stack, -1 means drop and 0 means decapsulated. */
223 static int gtp0_udp_encap_recv(struct gtp_dev
*gtp
, struct sk_buff
*skb
)
225 unsigned int hdrlen
= sizeof(struct udphdr
) +
226 sizeof(struct gtp0_header
);
227 struct gtp0_header
*gtp0
;
228 struct pdp_ctx
*pctx
;
230 if (!pskb_may_pull(skb
, hdrlen
))
233 gtp0
= (struct gtp0_header
*)(skb
->data
+ sizeof(struct udphdr
));
235 if ((gtp0
->flags
>> 5) != GTP_V0
)
238 if (gtp0
->type
!= GTP_TPDU
)
241 pctx
= gtp0_pdp_find(gtp
, be64_to_cpu(gtp0
->tid
));
243 netdev_dbg(gtp
->dev
, "No PDP ctx to decap skb=%p\n", skb
);
247 return gtp_rx(pctx
, skb
, hdrlen
, gtp
->role
);
250 static int gtp1u_udp_encap_recv(struct gtp_dev
*gtp
, struct sk_buff
*skb
)
252 unsigned int hdrlen
= sizeof(struct udphdr
) +
253 sizeof(struct gtp1_header
);
254 struct gtp1_header
*gtp1
;
255 struct pdp_ctx
*pctx
;
257 if (!pskb_may_pull(skb
, hdrlen
))
260 gtp1
= (struct gtp1_header
*)(skb
->data
+ sizeof(struct udphdr
));
262 if ((gtp1
->flags
>> 5) != GTP_V1
)
265 if (gtp1
->type
!= GTP_TPDU
)
268 /* From 29.060: "This field shall be present if and only if any one or
269 * more of the S, PN and E flags are set.".
271 * If any of the bit is set, then the remaining ones also have to be
274 if (gtp1
->flags
& GTP1_F_MASK
)
277 /* Make sure the header is larger enough, including extensions. */
278 if (!pskb_may_pull(skb
, hdrlen
))
281 gtp1
= (struct gtp1_header
*)(skb
->data
+ sizeof(struct udphdr
));
283 pctx
= gtp1_pdp_find(gtp
, ntohl(gtp1
->tid
));
285 netdev_dbg(gtp
->dev
, "No PDP ctx to decap skb=%p\n", skb
);
289 return gtp_rx(pctx
, skb
, hdrlen
, gtp
->role
);
292 static void gtp_encap_destroy(struct sock
*sk
)
296 gtp
= rcu_dereference_sk_user_data(sk
);
298 udp_sk(sk
)->encap_type
= 0;
299 rcu_assign_sk_user_data(sk
, NULL
);
304 static void gtp_encap_disable_sock(struct sock
*sk
)
309 gtp_encap_destroy(sk
);
312 static void gtp_encap_disable(struct gtp_dev
*gtp
)
314 gtp_encap_disable_sock(gtp
->sk0
);
315 gtp_encap_disable_sock(gtp
->sk1u
);
318 /* UDP encapsulation receive handler. See net/ipv4/udp.c.
319 * Return codes: 0: success, <0: error, >0: pass up to userspace UDP socket.
321 static int gtp_encap_recv(struct sock
*sk
, struct sk_buff
*skb
)
326 gtp
= rcu_dereference_sk_user_data(sk
);
330 netdev_dbg(gtp
->dev
, "encap_recv sk=%p\n", sk
);
332 switch (udp_sk(sk
)->encap_type
) {
334 netdev_dbg(gtp
->dev
, "received GTP0 packet\n");
335 ret
= gtp0_udp_encap_recv(gtp
, skb
);
337 case UDP_ENCAP_GTP1U
:
338 netdev_dbg(gtp
->dev
, "received GTP1U packet\n");
339 ret
= gtp1u_udp_encap_recv(gtp
, skb
);
342 ret
= -1; /* Shouldn't happen. */
347 netdev_dbg(gtp
->dev
, "pass up to the process\n");
352 netdev_dbg(gtp
->dev
, "GTP packet has been dropped\n");
361 static int gtp_dev_init(struct net_device
*dev
)
363 struct gtp_dev
*gtp
= netdev_priv(dev
);
367 dev
->tstats
= netdev_alloc_pcpu_stats(struct pcpu_sw_netstats
);
374 static void gtp_dev_uninit(struct net_device
*dev
)
376 struct gtp_dev
*gtp
= netdev_priv(dev
);
378 gtp_encap_disable(gtp
);
379 free_percpu(dev
->tstats
);
382 static struct rtable
*ip4_route_output_gtp(struct flowi4
*fl4
,
383 const struct sock
*sk
,
386 memset(fl4
, 0, sizeof(*fl4
));
387 fl4
->flowi4_oif
= sk
->sk_bound_dev_if
;
389 fl4
->saddr
= inet_sk(sk
)->inet_saddr
;
390 fl4
->flowi4_tos
= RT_CONN_FLAGS(sk
);
391 fl4
->flowi4_proto
= sk
->sk_protocol
;
393 return ip_route_output_key(sock_net(sk
), fl4
);
396 static inline void gtp0_push_header(struct sk_buff
*skb
, struct pdp_ctx
*pctx
)
398 int payload_len
= skb
->len
;
399 struct gtp0_header
*gtp0
;
401 gtp0
= skb_push(skb
, sizeof(*gtp0
));
403 gtp0
->flags
= 0x1e; /* v0, GTP-non-prime. */
404 gtp0
->type
= GTP_TPDU
;
405 gtp0
->length
= htons(payload_len
);
406 gtp0
->seq
= htons((atomic_inc_return(&pctx
->tx_seq
) - 1) % 0xffff);
407 gtp0
->flow
= htons(pctx
->u
.v0
.flow
);
409 gtp0
->spare
[0] = gtp0
->spare
[1] = gtp0
->spare
[2] = 0xff;
410 gtp0
->tid
= cpu_to_be64(pctx
->u
.v0
.tid
);
413 static inline void gtp1_push_header(struct sk_buff
*skb
, struct pdp_ctx
*pctx
)
415 int payload_len
= skb
->len
;
416 struct gtp1_header
*gtp1
;
418 gtp1
= skb_push(skb
, sizeof(*gtp1
));
420 /* Bits 8 7 6 5 4 3 2 1
421 * +--+--+--+--+--+--+--+--+
422 * |version |PT| 0| E| S|PN|
423 * +--+--+--+--+--+--+--+--+
426 gtp1
->flags
= 0x30; /* v1, GTP-non-prime. */
427 gtp1
->type
= GTP_TPDU
;
428 gtp1
->length
= htons(payload_len
);
429 gtp1
->tid
= htonl(pctx
->u
.v1
.o_tei
);
431 /* TODO: Suppport for extension header, sequence number and N-PDU.
432 * Update the length field if any of them is available.
441 struct pdp_ctx
*pctx
;
442 struct net_device
*dev
;
446 static void gtp_push_header(struct sk_buff
*skb
, struct gtp_pktinfo
*pktinfo
)
448 switch (pktinfo
->pctx
->gtp_version
) {
450 pktinfo
->gtph_port
= htons(GTP0_PORT
);
451 gtp0_push_header(skb
, pktinfo
->pctx
);
454 pktinfo
->gtph_port
= htons(GTP1U_PORT
);
455 gtp1_push_header(skb
, pktinfo
->pctx
);
460 static inline void gtp_set_pktinfo_ipv4(struct gtp_pktinfo
*pktinfo
,
461 struct sock
*sk
, struct iphdr
*iph
,
462 struct pdp_ctx
*pctx
, struct rtable
*rt
,
464 struct net_device
*dev
)
468 pktinfo
->pctx
= pctx
;
474 static int gtp_build_skb_ip4(struct sk_buff
*skb
, struct net_device
*dev
,
475 struct gtp_pktinfo
*pktinfo
)
477 struct gtp_dev
*gtp
= netdev_priv(dev
);
478 struct pdp_ctx
*pctx
;
485 /* Read the IP destination address and resolve the PDP context.
486 * Prepend PDP header with TEI/TID from PDP ctx.
489 if (gtp
->role
== GTP_ROLE_SGSN
)
490 pctx
= ipv4_pdp_find(gtp
, iph
->saddr
);
492 pctx
= ipv4_pdp_find(gtp
, iph
->daddr
);
495 netdev_dbg(dev
, "no PDP ctx found for %pI4, skip\n",
499 netdev_dbg(dev
, "found PDP context %p\n", pctx
);
501 rt
= ip4_route_output_gtp(&fl4
, pctx
->sk
, pctx
->peer_addr_ip4
.s_addr
);
503 netdev_dbg(dev
, "no route to SSGN %pI4\n",
504 &pctx
->peer_addr_ip4
.s_addr
);
505 dev
->stats
.tx_carrier_errors
++;
509 if (rt
->dst
.dev
== dev
) {
510 netdev_dbg(dev
, "circular route to SSGN %pI4\n",
511 &pctx
->peer_addr_ip4
.s_addr
);
512 dev
->stats
.collisions
++;
518 /* This is similar to tnl_update_pmtu(). */
521 mtu
= dst_mtu(&rt
->dst
) - dev
->hard_header_len
-
522 sizeof(struct iphdr
) - sizeof(struct udphdr
);
523 switch (pctx
->gtp_version
) {
525 mtu
-= sizeof(struct gtp0_header
);
528 mtu
-= sizeof(struct gtp1_header
);
532 mtu
= dst_mtu(&rt
->dst
);
535 rt
->dst
.ops
->update_pmtu(&rt
->dst
, NULL
, skb
, mtu
);
537 if (!skb_is_gso(skb
) && (iph
->frag_off
& htons(IP_DF
)) &&
538 mtu
< ntohs(iph
->tot_len
)) {
539 netdev_dbg(dev
, "packet too big, fragmentation needed\n");
540 memset(IPCB(skb
), 0, sizeof(*IPCB(skb
)));
541 icmp_send(skb
, ICMP_DEST_UNREACH
, ICMP_FRAG_NEEDED
,
546 gtp_set_pktinfo_ipv4(pktinfo
, pctx
->sk
, iph
, pctx
, rt
, &fl4
, dev
);
547 gtp_push_header(skb
, pktinfo
);
556 static netdev_tx_t
gtp_dev_xmit(struct sk_buff
*skb
, struct net_device
*dev
)
558 unsigned int proto
= ntohs(skb
->protocol
);
559 struct gtp_pktinfo pktinfo
;
562 /* Ensure there is sufficient headroom. */
563 if (skb_cow_head(skb
, dev
->needed_headroom
))
566 skb_reset_inner_headers(skb
);
568 /* PDP context lookups in gtp_build_skb_*() need rcu read-side lock. */
572 err
= gtp_build_skb_ip4(skb
, dev
, &pktinfo
);
585 netdev_dbg(pktinfo
.dev
, "gtp -> IP src: %pI4 dst: %pI4\n",
586 &pktinfo
.iph
->saddr
, &pktinfo
.iph
->daddr
);
587 udp_tunnel_xmit_skb(pktinfo
.rt
, pktinfo
.sk
, skb
,
588 pktinfo
.fl4
.saddr
, pktinfo
.fl4
.daddr
,
590 ip4_dst_hoplimit(&pktinfo
.rt
->dst
),
592 pktinfo
.gtph_port
, pktinfo
.gtph_port
,
599 dev
->stats
.tx_errors
++;
604 static const struct net_device_ops gtp_netdev_ops
= {
605 .ndo_init
= gtp_dev_init
,
606 .ndo_uninit
= gtp_dev_uninit
,
607 .ndo_start_xmit
= gtp_dev_xmit
,
608 .ndo_get_stats64
= ip_tunnel_get_stats64
,
611 static void gtp_link_setup(struct net_device
*dev
)
613 dev
->netdev_ops
= >p_netdev_ops
;
614 dev
->needs_free_netdev
= true;
616 dev
->hard_header_len
= 0;
619 /* Zero header length. */
620 dev
->type
= ARPHRD_NONE
;
621 dev
->flags
= IFF_POINTOPOINT
| IFF_NOARP
| IFF_MULTICAST
;
623 dev
->priv_flags
|= IFF_NO_QUEUE
;
624 dev
->features
|= NETIF_F_LLTX
;
627 /* Assume largest header, ie. GTPv0. */
628 dev
->needed_headroom
= LL_MAX_HEADER
+
629 sizeof(struct iphdr
) +
630 sizeof(struct udphdr
) +
631 sizeof(struct gtp0_header
);
634 static int gtp_hashtable_new(struct gtp_dev
*gtp
, int hsize
);
635 static void gtp_hashtable_free(struct gtp_dev
*gtp
);
636 static int gtp_encap_enable(struct gtp_dev
*gtp
, struct nlattr
*data
[]);
638 static int gtp_newlink(struct net
*src_net
, struct net_device
*dev
,
639 struct nlattr
*tb
[], struct nlattr
*data
[],
640 struct netlink_ext_ack
*extack
)
646 if (!data
[IFLA_GTP_FD0
] && !data
[IFLA_GTP_FD1
])
649 gtp
= netdev_priv(dev
);
651 err
= gtp_encap_enable(gtp
, data
);
655 if (!data
[IFLA_GTP_PDP_HASHSIZE
])
658 hashsize
= nla_get_u32(data
[IFLA_GTP_PDP_HASHSIZE
]);
660 err
= gtp_hashtable_new(gtp
, hashsize
);
664 err
= register_netdevice(dev
);
666 netdev_dbg(dev
, "failed to register new netdev %d\n", err
);
670 gn
= net_generic(dev_net(dev
), gtp_net_id
);
671 list_add_rcu(>p
->list
, &gn
->gtp_dev_list
);
673 netdev_dbg(dev
, "registered new GTP interface\n");
678 gtp_hashtable_free(gtp
);
680 gtp_encap_disable(gtp
);
684 static void gtp_dellink(struct net_device
*dev
, struct list_head
*head
)
686 struct gtp_dev
*gtp
= netdev_priv(dev
);
688 gtp_encap_disable(gtp
);
689 gtp_hashtable_free(gtp
);
690 list_del_rcu(>p
->list
);
691 unregister_netdevice_queue(dev
, head
);
694 static const struct nla_policy gtp_policy
[IFLA_GTP_MAX
+ 1] = {
695 [IFLA_GTP_FD0
] = { .type
= NLA_U32
},
696 [IFLA_GTP_FD1
] = { .type
= NLA_U32
},
697 [IFLA_GTP_PDP_HASHSIZE
] = { .type
= NLA_U32
},
698 [IFLA_GTP_ROLE
] = { .type
= NLA_U32
},
701 static int gtp_validate(struct nlattr
*tb
[], struct nlattr
*data
[],
702 struct netlink_ext_ack
*extack
)
710 static size_t gtp_get_size(const struct net_device
*dev
)
712 return nla_total_size(sizeof(__u32
)); /* IFLA_GTP_PDP_HASHSIZE */
715 static int gtp_fill_info(struct sk_buff
*skb
, const struct net_device
*dev
)
717 struct gtp_dev
*gtp
= netdev_priv(dev
);
719 if (nla_put_u32(skb
, IFLA_GTP_PDP_HASHSIZE
, gtp
->hash_size
))
720 goto nla_put_failure
;
728 static struct rtnl_link_ops gtp_link_ops __read_mostly
= {
730 .maxtype
= IFLA_GTP_MAX
,
731 .policy
= gtp_policy
,
732 .priv_size
= sizeof(struct gtp_dev
),
733 .setup
= gtp_link_setup
,
734 .validate
= gtp_validate
,
735 .newlink
= gtp_newlink
,
736 .dellink
= gtp_dellink
,
737 .get_size
= gtp_get_size
,
738 .fill_info
= gtp_fill_info
,
741 static int gtp_hashtable_new(struct gtp_dev
*gtp
, int hsize
)
745 gtp
->addr_hash
= kmalloc(sizeof(struct hlist_head
) * hsize
, GFP_KERNEL
);
746 if (gtp
->addr_hash
== NULL
)
749 gtp
->tid_hash
= kmalloc(sizeof(struct hlist_head
) * hsize
, GFP_KERNEL
);
750 if (gtp
->tid_hash
== NULL
)
753 gtp
->hash_size
= hsize
;
755 for (i
= 0; i
< hsize
; i
++) {
756 INIT_HLIST_HEAD(>p
->addr_hash
[i
]);
757 INIT_HLIST_HEAD(>p
->tid_hash
[i
]);
761 kfree(gtp
->addr_hash
);
765 static void gtp_hashtable_free(struct gtp_dev
*gtp
)
767 struct pdp_ctx
*pctx
;
770 for (i
= 0; i
< gtp
->hash_size
; i
++)
771 hlist_for_each_entry_rcu(pctx
, >p
->tid_hash
[i
], hlist_tid
)
772 pdp_context_delete(pctx
);
775 kfree(gtp
->addr_hash
);
776 kfree(gtp
->tid_hash
);
779 static struct sock
*gtp_encap_enable_socket(int fd
, int type
,
782 struct udp_tunnel_sock_cfg tuncfg
= {NULL
};
787 pr_debug("enable gtp on %d, %d\n", fd
, type
);
789 sock
= sockfd_lookup(fd
, &err
);
791 pr_debug("gtp socket fd=%d not found\n", fd
);
795 if (sock
->sk
->sk_protocol
!= IPPROTO_UDP
) {
796 pr_debug("socket fd=%d not UDP\n", fd
);
797 sk
= ERR_PTR(-EINVAL
);
801 if (rcu_dereference_sk_user_data(sock
->sk
)) {
802 sk
= ERR_PTR(-EBUSY
);
809 tuncfg
.sk_user_data
= gtp
;
810 tuncfg
.encap_type
= type
;
811 tuncfg
.encap_rcv
= gtp_encap_recv
;
812 tuncfg
.encap_destroy
= gtp_encap_destroy
;
814 setup_udp_tunnel_sock(sock_net(sock
->sk
), sock
, &tuncfg
);
821 static int gtp_encap_enable(struct gtp_dev
*gtp
, struct nlattr
*data
[])
823 struct sock
*sk1u
= NULL
;
824 struct sock
*sk0
= NULL
;
825 unsigned int role
= GTP_ROLE_GGSN
;
827 if (data
[IFLA_GTP_FD0
]) {
828 u32 fd0
= nla_get_u32(data
[IFLA_GTP_FD0
]);
830 sk0
= gtp_encap_enable_socket(fd0
, UDP_ENCAP_GTP0
, gtp
);
835 if (data
[IFLA_GTP_FD1
]) {
836 u32 fd1
= nla_get_u32(data
[IFLA_GTP_FD1
]);
838 sk1u
= gtp_encap_enable_socket(fd1
, UDP_ENCAP_GTP1U
, gtp
);
841 gtp_encap_disable_sock(sk0
);
842 return PTR_ERR(sk1u
);
846 if (data
[IFLA_GTP_ROLE
]) {
847 role
= nla_get_u32(data
[IFLA_GTP_ROLE
]);
848 if (role
> GTP_ROLE_SGSN
)
859 static struct gtp_dev
*gtp_find_dev(struct net
*src_net
, struct nlattr
*nla
[])
861 struct gtp_dev
*gtp
= NULL
;
862 struct net_device
*dev
;
865 /* Examine the link attributes and figure out which network namespace
866 * we are talking about.
868 if (nla
[GTPA_NET_NS_FD
])
869 net
= get_net_ns_by_fd(nla_get_u32(nla
[GTPA_NET_NS_FD
]));
871 net
= get_net(src_net
);
876 /* Check if there's an existing gtpX device to configure */
877 dev
= dev_get_by_index_rcu(net
, nla_get_u32(nla
[GTPA_LINK
]));
878 if (dev
&& dev
->netdev_ops
== >p_netdev_ops
)
879 gtp
= netdev_priv(dev
);
885 static void ipv4_pdp_fill(struct pdp_ctx
*pctx
, struct genl_info
*info
)
887 pctx
->gtp_version
= nla_get_u32(info
->attrs
[GTPA_VERSION
]);
889 pctx
->peer_addr_ip4
.s_addr
=
890 nla_get_be32(info
->attrs
[GTPA_PEER_ADDRESS
]);
891 pctx
->ms_addr_ip4
.s_addr
=
892 nla_get_be32(info
->attrs
[GTPA_MS_ADDRESS
]);
894 switch (pctx
->gtp_version
) {
896 /* According to TS 09.60, sections 7.5.1 and 7.5.2, the flow
897 * label needs to be the same for uplink and downlink packets,
898 * so let's annotate this.
900 pctx
->u
.v0
.tid
= nla_get_u64(info
->attrs
[GTPA_TID
]);
901 pctx
->u
.v0
.flow
= nla_get_u16(info
->attrs
[GTPA_FLOW
]);
904 pctx
->u
.v1
.i_tei
= nla_get_u32(info
->attrs
[GTPA_I_TEI
]);
905 pctx
->u
.v1
.o_tei
= nla_get_u32(info
->attrs
[GTPA_O_TEI
]);
912 static int ipv4_pdp_add(struct gtp_dev
*gtp
, struct sock
*sk
,
913 struct genl_info
*info
)
915 struct net_device
*dev
= gtp
->dev
;
916 u32 hash_ms
, hash_tid
= 0;
917 struct pdp_ctx
*pctx
;
921 ms_addr
= nla_get_be32(info
->attrs
[GTPA_MS_ADDRESS
]);
922 hash_ms
= ipv4_hashfn(ms_addr
) % gtp
->hash_size
;
924 hlist_for_each_entry_rcu(pctx
, >p
->addr_hash
[hash_ms
], hlist_addr
) {
925 if (pctx
->ms_addr_ip4
.s_addr
== ms_addr
) {
932 if (info
->nlhdr
->nlmsg_flags
& NLM_F_EXCL
)
934 if (info
->nlhdr
->nlmsg_flags
& NLM_F_REPLACE
)
937 ipv4_pdp_fill(pctx
, info
);
939 if (pctx
->gtp_version
== GTP_V0
)
940 netdev_dbg(dev
, "GTPv0-U: update tunnel id = %llx (pdp %p)\n",
941 pctx
->u
.v0
.tid
, pctx
);
942 else if (pctx
->gtp_version
== GTP_V1
)
943 netdev_dbg(dev
, "GTPv1-U: update tunnel id = %x/%x (pdp %p)\n",
944 pctx
->u
.v1
.i_tei
, pctx
->u
.v1
.o_tei
, pctx
);
950 pctx
= kmalloc(sizeof(struct pdp_ctx
), GFP_KERNEL
);
956 pctx
->dev
= gtp
->dev
;
957 ipv4_pdp_fill(pctx
, info
);
958 atomic_set(&pctx
->tx_seq
, 0);
960 switch (pctx
->gtp_version
) {
962 /* TS 09.60: "The flow label identifies unambiguously a GTP
963 * flow.". We use the tid for this instead, I cannot find a
964 * situation in which this doesn't unambiguosly identify the
967 hash_tid
= gtp0_hashfn(pctx
->u
.v0
.tid
) % gtp
->hash_size
;
970 hash_tid
= gtp1u_hashfn(pctx
->u
.v1
.i_tei
) % gtp
->hash_size
;
974 hlist_add_head_rcu(&pctx
->hlist_addr
, >p
->addr_hash
[hash_ms
]);
975 hlist_add_head_rcu(&pctx
->hlist_tid
, >p
->tid_hash
[hash_tid
]);
977 switch (pctx
->gtp_version
) {
979 netdev_dbg(dev
, "GTPv0-U: new PDP ctx id=%llx ssgn=%pI4 ms=%pI4 (pdp=%p)\n",
980 pctx
->u
.v0
.tid
, &pctx
->peer_addr_ip4
,
981 &pctx
->ms_addr_ip4
, pctx
);
984 netdev_dbg(dev
, "GTPv1-U: new PDP ctx id=%x/%x ssgn=%pI4 ms=%pI4 (pdp=%p)\n",
985 pctx
->u
.v1
.i_tei
, pctx
->u
.v1
.o_tei
,
986 &pctx
->peer_addr_ip4
, &pctx
->ms_addr_ip4
, pctx
);
993 static void pdp_context_free(struct rcu_head
*head
)
995 struct pdp_ctx
*pctx
= container_of(head
, struct pdp_ctx
, rcu_head
);
1001 static void pdp_context_delete(struct pdp_ctx
*pctx
)
1003 hlist_del_rcu(&pctx
->hlist_tid
);
1004 hlist_del_rcu(&pctx
->hlist_addr
);
1005 call_rcu(&pctx
->rcu_head
, pdp_context_free
);
1008 static int gtp_genl_new_pdp(struct sk_buff
*skb
, struct genl_info
*info
)
1010 unsigned int version
;
1011 struct gtp_dev
*gtp
;
1015 if (!info
->attrs
[GTPA_VERSION
] ||
1016 !info
->attrs
[GTPA_LINK
] ||
1017 !info
->attrs
[GTPA_PEER_ADDRESS
] ||
1018 !info
->attrs
[GTPA_MS_ADDRESS
])
1021 version
= nla_get_u32(info
->attrs
[GTPA_VERSION
]);
1025 if (!info
->attrs
[GTPA_TID
] ||
1026 !info
->attrs
[GTPA_FLOW
])
1030 if (!info
->attrs
[GTPA_I_TEI
] ||
1031 !info
->attrs
[GTPA_O_TEI
])
1041 gtp
= gtp_find_dev(sock_net(skb
->sk
), info
->attrs
);
1047 if (version
== GTP_V0
)
1049 else if (version
== GTP_V1
)
1059 err
= ipv4_pdp_add(gtp
, sk
, info
);
1066 static struct pdp_ctx
*gtp_find_pdp_by_link(struct net
*net
,
1067 struct nlattr
*nla
[])
1069 struct gtp_dev
*gtp
;
1071 gtp
= gtp_find_dev(net
, nla
);
1073 return ERR_PTR(-ENODEV
);
1075 if (nla
[GTPA_MS_ADDRESS
]) {
1076 __be32 ip
= nla_get_be32(nla
[GTPA_MS_ADDRESS
]);
1078 return ipv4_pdp_find(gtp
, ip
);
1079 } else if (nla
[GTPA_VERSION
]) {
1080 u32 gtp_version
= nla_get_u32(nla
[GTPA_VERSION
]);
1082 if (gtp_version
== GTP_V0
&& nla
[GTPA_TID
])
1083 return gtp0_pdp_find(gtp
, nla_get_u64(nla
[GTPA_TID
]));
1084 else if (gtp_version
== GTP_V1
&& nla
[GTPA_I_TEI
])
1085 return gtp1_pdp_find(gtp
, nla_get_u32(nla
[GTPA_I_TEI
]));
1088 return ERR_PTR(-EINVAL
);
1091 static struct pdp_ctx
*gtp_find_pdp(struct net
*net
, struct nlattr
*nla
[])
1093 struct pdp_ctx
*pctx
;
1096 pctx
= gtp_find_pdp_by_link(net
, nla
);
1098 pctx
= ERR_PTR(-EINVAL
);
1101 pctx
= ERR_PTR(-ENOENT
);
1106 static int gtp_genl_del_pdp(struct sk_buff
*skb
, struct genl_info
*info
)
1108 struct pdp_ctx
*pctx
;
1111 if (!info
->attrs
[GTPA_VERSION
])
1116 pctx
= gtp_find_pdp(sock_net(skb
->sk
), info
->attrs
);
1118 err
= PTR_ERR(pctx
);
1122 if (pctx
->gtp_version
== GTP_V0
)
1123 netdev_dbg(pctx
->dev
, "GTPv0-U: deleting tunnel id = %llx (pdp %p)\n",
1124 pctx
->u
.v0
.tid
, pctx
);
1125 else if (pctx
->gtp_version
== GTP_V1
)
1126 netdev_dbg(pctx
->dev
, "GTPv1-U: deleting tunnel id = %x/%x (pdp %p)\n",
1127 pctx
->u
.v1
.i_tei
, pctx
->u
.v1
.o_tei
, pctx
);
1129 pdp_context_delete(pctx
);
1136 static struct genl_family gtp_genl_family
;
1138 static int gtp_genl_fill_info(struct sk_buff
*skb
, u32 snd_portid
, u32 snd_seq
,
1139 u32 type
, struct pdp_ctx
*pctx
)
1143 genlh
= genlmsg_put(skb
, snd_portid
, snd_seq
, >p_genl_family
, 0,
1148 if (nla_put_u32(skb
, GTPA_VERSION
, pctx
->gtp_version
) ||
1149 nla_put_be32(skb
, GTPA_PEER_ADDRESS
, pctx
->peer_addr_ip4
.s_addr
) ||
1150 nla_put_be32(skb
, GTPA_MS_ADDRESS
, pctx
->ms_addr_ip4
.s_addr
))
1151 goto nla_put_failure
;
1153 switch (pctx
->gtp_version
) {
1155 if (nla_put_u64_64bit(skb
, GTPA_TID
, pctx
->u
.v0
.tid
, GTPA_PAD
) ||
1156 nla_put_u16(skb
, GTPA_FLOW
, pctx
->u
.v0
.flow
))
1157 goto nla_put_failure
;
1160 if (nla_put_u32(skb
, GTPA_I_TEI
, pctx
->u
.v1
.i_tei
) ||
1161 nla_put_u32(skb
, GTPA_O_TEI
, pctx
->u
.v1
.o_tei
))
1162 goto nla_put_failure
;
1165 genlmsg_end(skb
, genlh
);
1170 genlmsg_cancel(skb
, genlh
);
1174 static int gtp_genl_get_pdp(struct sk_buff
*skb
, struct genl_info
*info
)
1176 struct pdp_ctx
*pctx
= NULL
;
1177 struct sk_buff
*skb2
;
1180 if (!info
->attrs
[GTPA_VERSION
])
1185 pctx
= gtp_find_pdp(sock_net(skb
->sk
), info
->attrs
);
1187 err
= PTR_ERR(pctx
);
1191 skb2
= genlmsg_new(NLMSG_GOODSIZE
, GFP_ATOMIC
);
1197 err
= gtp_genl_fill_info(skb2
, NETLINK_CB(skb
).portid
,
1198 info
->snd_seq
, info
->nlhdr
->nlmsg_type
, pctx
);
1200 goto err_unlock_free
;
1203 return genlmsg_unicast(genl_info_net(info
), skb2
, info
->snd_portid
);
1212 static int gtp_genl_dump_pdp(struct sk_buff
*skb
,
1213 struct netlink_callback
*cb
)
1215 struct gtp_dev
*last_gtp
= (struct gtp_dev
*)cb
->args
[2], *gtp
;
1216 struct net
*net
= sock_net(skb
->sk
);
1217 struct gtp_net
*gn
= net_generic(net
, gtp_net_id
);
1218 unsigned long tid
= cb
->args
[1];
1219 int i
, k
= cb
->args
[0], ret
;
1220 struct pdp_ctx
*pctx
;
1225 list_for_each_entry_rcu(gtp
, &gn
->gtp_dev_list
, list
) {
1226 if (last_gtp
&& last_gtp
!= gtp
)
1231 for (i
= k
; i
< gtp
->hash_size
; i
++) {
1232 hlist_for_each_entry_rcu(pctx
, >p
->tid_hash
[i
], hlist_tid
) {
1233 if (tid
&& tid
!= pctx
->u
.tid
)
1238 ret
= gtp_genl_fill_info(skb
,
1239 NETLINK_CB(cb
->skb
).portid
,
1241 cb
->nlh
->nlmsg_type
, pctx
);
1244 cb
->args
[1] = pctx
->u
.tid
;
1245 cb
->args
[2] = (unsigned long)gtp
;
1256 static struct nla_policy gtp_genl_policy
[GTPA_MAX
+ 1] = {
1257 [GTPA_LINK
] = { .type
= NLA_U32
, },
1258 [GTPA_VERSION
] = { .type
= NLA_U32
, },
1259 [GTPA_TID
] = { .type
= NLA_U64
, },
1260 [GTPA_PEER_ADDRESS
] = { .type
= NLA_U32
, },
1261 [GTPA_MS_ADDRESS
] = { .type
= NLA_U32
, },
1262 [GTPA_FLOW
] = { .type
= NLA_U16
, },
1263 [GTPA_NET_NS_FD
] = { .type
= NLA_U32
, },
1264 [GTPA_I_TEI
] = { .type
= NLA_U32
, },
1265 [GTPA_O_TEI
] = { .type
= NLA_U32
, },
1268 static const struct genl_ops gtp_genl_ops
[] = {
1270 .cmd
= GTP_CMD_NEWPDP
,
1271 .doit
= gtp_genl_new_pdp
,
1272 .policy
= gtp_genl_policy
,
1273 .flags
= GENL_ADMIN_PERM
,
1276 .cmd
= GTP_CMD_DELPDP
,
1277 .doit
= gtp_genl_del_pdp
,
1278 .policy
= gtp_genl_policy
,
1279 .flags
= GENL_ADMIN_PERM
,
1282 .cmd
= GTP_CMD_GETPDP
,
1283 .doit
= gtp_genl_get_pdp
,
1284 .dumpit
= gtp_genl_dump_pdp
,
1285 .policy
= gtp_genl_policy
,
1286 .flags
= GENL_ADMIN_PERM
,
1290 static struct genl_family gtp_genl_family __ro_after_init
= {
1294 .maxattr
= GTPA_MAX
,
1296 .module
= THIS_MODULE
,
1297 .ops
= gtp_genl_ops
,
1298 .n_ops
= ARRAY_SIZE(gtp_genl_ops
),
1301 static int __net_init
gtp_net_init(struct net
*net
)
1303 struct gtp_net
*gn
= net_generic(net
, gtp_net_id
);
1305 INIT_LIST_HEAD(&gn
->gtp_dev_list
);
1309 static void __net_exit
gtp_net_exit(struct net
*net
)
1311 struct gtp_net
*gn
= net_generic(net
, gtp_net_id
);
1312 struct gtp_dev
*gtp
;
1316 list_for_each_entry(gtp
, &gn
->gtp_dev_list
, list
)
1317 gtp_dellink(gtp
->dev
, &list
);
1319 unregister_netdevice_many(&list
);
1323 static struct pernet_operations gtp_net_ops
= {
1324 .init
= gtp_net_init
,
1325 .exit
= gtp_net_exit
,
1327 .size
= sizeof(struct gtp_net
),
1330 static int __init
gtp_init(void)
1334 get_random_bytes(>p_h_initval
, sizeof(gtp_h_initval
));
1336 err
= rtnl_link_register(>p_link_ops
);
1340 err
= genl_register_family(>p_genl_family
);
1342 goto unreg_rtnl_link
;
1344 err
= register_pernet_subsys(>p_net_ops
);
1346 goto unreg_genl_family
;
1348 pr_info("GTP module loaded (pdp ctx size %zd bytes)\n",
1349 sizeof(struct pdp_ctx
));
1353 genl_unregister_family(>p_genl_family
);
1355 rtnl_link_unregister(>p_link_ops
);
1357 pr_err("error loading GTP module loaded\n");
1360 late_initcall(gtp_init
);
1362 static void __exit
gtp_fini(void)
1364 unregister_pernet_subsys(>p_net_ops
);
1365 genl_unregister_family(>p_genl_family
);
1366 rtnl_link_unregister(>p_link_ops
);
1368 pr_info("GTP module unloaded\n");
1370 module_exit(gtp_fini
);
1372 MODULE_LICENSE("GPL");
1373 MODULE_AUTHOR("Harald Welte <hwelte@sysmocom.de>");
1374 MODULE_DESCRIPTION("Interface driver for GTP encapsulated traffic");
1375 MODULE_ALIAS_RTNL_LINK("gtp");
1376 MODULE_ALIAS_GENL_FAMILY("gtp");