14 Commits

Author SHA1 Message Date
Yoshiyuki Kurauchi
2e7f7b28c4 gtp: set NLM_F_MULTI flag in gtp_genl_dump_pdp()
[ Upstream commit 846c68f7f1ac82c797a2f1db3344a2966c0fe2e1 ]

In drivers/net/gtp.c, gtp_genl_dump_pdp() should set NLM_F_MULTI
flag since it returns multipart message.
This patch adds a new arg "flags" in gtp_genl_fill_info() so that
flags can be set by the callers.

Signed-off-by: Yoshiyuki Kurauchi <ahochauwaaaaa@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-27 16:41:47 +02:00
Taehee Yoo
16c0f9433b gtp: use __GFP_NOWARN to avoid memalloc warning
[ Upstream commit bd5cd35b782abf5437fbd01dfaee12437d20e832 ]

gtp hashtable size is received by user-space.
So, this hashtable size could be too large. If so, kmalloc will internally
print a warning message.
This warning message is actually not necessary for the gtp module.
So, this patch adds __GFP_NOWARN to avoid this message.

Splat looks like:
[ 2171.200049][ T1860] WARNING: CPU: 1 PID: 1860 at mm/page_alloc.c:4713 __alloc_pages_nodemask+0x2f3/0x740
[ 2171.238885][ T1860] Modules linked in: gtp veth openvswitch nsh nf_conncount nf_nat nf_conntrack nf_defrag_ipv]
[ 2171.262680][ T1860] CPU: 1 PID: 1860 Comm: gtp-link Not tainted 5.5.0+ #321
[ 2171.263567][ T1860] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[ 2171.264681][ T1860] RIP: 0010:__alloc_pages_nodemask+0x2f3/0x740
[ 2171.265332][ T1860] Code: 64 fe ff ff 65 48 8b 04 25 c0 0f 02 00 48 05 f0 12 00 00 41 be 01 00 00 00 49 89 47 0
[ 2171.267301][ T1860] RSP: 0018:ffff8880b51af1f0 EFLAGS: 00010246
[ 2171.268320][ T1860] RAX: ffffed1016a35e43 RBX: 0000000000000000 RCX: 0000000000000000
[ 2171.269517][ T1860] RDX: 0000000000000000 RSI: 000000000000000b RDI: 0000000000000000
[ 2171.270305][ T1860] RBP: 0000000000040cc0 R08: ffffed1018893109 R09: dffffc0000000000
[ 2171.275973][ T1860] R10: 0000000000000001 R11: ffffed1018893108 R12: 1ffff11016a35e43
[ 2171.291039][ T1860] R13: 000000000000000b R14: 000000000000000b R15: 00000000000f4240
[ 2171.292328][ T1860] FS:  00007f53cbc83740(0000) GS:ffff8880da000000(0000) knlGS:0000000000000000
[ 2171.293409][ T1860] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 2171.294586][ T1860] CR2: 000055f540014508 CR3: 00000000b49f2004 CR4: 00000000000606e0
[ 2171.295424][ T1860] Call Trace:
[ 2171.295756][ T1860]  ? mark_held_locks+0xa5/0xe0
[ 2171.296659][ T1860]  ? __alloc_pages_slowpath+0x21b0/0x21b0
[ 2171.298283][ T1860]  ? gtp_encap_enable_socket+0x13e/0x400 [gtp]
[ 2171.298962][ T1860]  ? alloc_pages_current+0xc1/0x1a0
[ 2171.299475][ T1860]  kmalloc_order+0x22/0x80
[ 2171.299936][ T1860]  kmalloc_order_trace+0x1d/0x140
[ 2171.300437][ T1860]  __kmalloc+0x302/0x3a0
[ 2171.300896][ T1860]  gtp_newlink+0x293/0xba0 [gtp]
[ ... ]

Fixes: 459aa660eb1d ("gtp: add initial driver for datapath of GPRS Tunneling Protocol (GTP-U)")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-14 16:30:58 -05:00
Eric Dumazet
3410eb22b6 gtp: make sure only SOCK_DGRAM UDP sockets are accepted
[ Upstream commit 940ba14986657a50c15f694efca1beba31fa568f ]

A malicious user could use RAW sockets and fool
GTP using them as standard SOCK_DGRAM UDP sockets.

BUG: KMSAN: uninit-value in udp_tunnel_encap_enable include/net/udp_tunnel.h:174 [inline]
BUG: KMSAN: uninit-value in setup_udp_tunnel_sock+0x45e/0x6f0 net/ipv4/udp_tunnel.c:85
CPU: 0 PID: 11262 Comm: syz-executor613 Not tainted 5.5.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1c9/0x220 lib/dump_stack.c:118
 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:118
 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215
 udp_tunnel_encap_enable include/net/udp_tunnel.h:174 [inline]
 setup_udp_tunnel_sock+0x45e/0x6f0 net/ipv4/udp_tunnel.c:85
 gtp_encap_enable_socket+0x37f/0x5a0 drivers/net/gtp.c:827
 gtp_encap_enable drivers/net/gtp.c:844 [inline]
 gtp_newlink+0xfb/0x1e50 drivers/net/gtp.c:666
 __rtnl_newlink net/core/rtnetlink.c:3305 [inline]
 rtnl_newlink+0x2973/0x3920 net/core/rtnetlink.c:3363
 rtnetlink_rcv_msg+0x1153/0x1570 net/core/rtnetlink.c:5424
 netlink_rcv_skb+0x451/0x650 net/netlink/af_netlink.c:2477
 rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:5442
 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline]
 netlink_unicast+0xf9e/0x1100 net/netlink/af_netlink.c:1328
 netlink_sendmsg+0x1248/0x14d0 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:639 [inline]
 sock_sendmsg net/socket.c:659 [inline]
 ____sys_sendmsg+0x12b6/0x1350 net/socket.c:2330
 ___sys_sendmsg net/socket.c:2384 [inline]
 __sys_sendmsg+0x451/0x5f0 net/socket.c:2417
 __do_sys_sendmsg net/socket.c:2426 [inline]
 __se_sys_sendmsg+0x97/0xb0 net/socket.c:2424
 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2424
 do_syscall_64+0xb8/0x160 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x441359
Code: e8 ac e8 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 eb 08 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fff1cd0ac28 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441359
RDX: 0000000000000000 RSI: 0000000020000100 RDI: 0000000000000003
RBP: 00000000006cb018 R08: 00000000004002c8 R09: 00000000004002c8
R10: 00000000004002c8 R11: 0000000000000246 R12: 00000000004020d0
R13: 0000000000402160 R14: 0000000000000000 R15: 0000000000000000

Uninit was created at:
 kmsan_save_stack_with_flags+0x3c/0x90 mm/kmsan/kmsan.c:144
 kmsan_internal_alloc_meta_for_pages mm/kmsan/kmsan_shadow.c:307 [inline]
 kmsan_alloc_page+0x12a/0x310 mm/kmsan/kmsan_shadow.c:336
 __alloc_pages_nodemask+0x57f2/0x5f60 mm/page_alloc.c:4800
 alloc_pages_current+0x67d/0x990 mm/mempolicy.c:2207
 alloc_pages include/linux/gfp.h:534 [inline]
 alloc_slab_page+0x111/0x12f0 mm/slub.c:1511
 allocate_slab mm/slub.c:1656 [inline]
 new_slab+0x2bc/0x1130 mm/slub.c:1722
 new_slab_objects mm/slub.c:2473 [inline]
 ___slab_alloc+0x1533/0x1f30 mm/slub.c:2624
 __slab_alloc mm/slub.c:2664 [inline]
 slab_alloc_node mm/slub.c:2738 [inline]
 slab_alloc mm/slub.c:2783 [inline]
 kmem_cache_alloc+0xb23/0xd70 mm/slub.c:2788
 sk_prot_alloc+0xf2/0x620 net/core/sock.c:1597
 sk_alloc+0xf0/0xbe0 net/core/sock.c:1657
 inet_create+0x7c7/0x1370 net/ipv4/af_inet.c:321
 __sock_create+0x8eb/0xf00 net/socket.c:1420
 sock_create net/socket.c:1471 [inline]
 __sys_socket+0x1a1/0x600 net/socket.c:1513
 __do_sys_socket net/socket.c:1522 [inline]
 __se_sys_socket+0x8d/0xb0 net/socket.c:1520
 __x64_sys_socket+0x4a/0x70 net/socket.c:1520
 do_syscall_64+0xb8/0x160 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fixes: 459aa660eb1d ("gtp: add initial driver for datapath of GPRS Tunneling Protocol (GTP-U)")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Pablo Neira <pablo@netfilter.org>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-29 10:24:37 +01:00
Taehee Yoo
3db5dee970 gtp: avoid zero size hashtable
[ Upstream commit 6a902c0f31993ab02e1b6ea7085002b9c9083b6a ]

GTP default hashtable size is 1024 and userspace could set specific
hashtable size with IFLA_GTP_PDP_HASHSIZE. If hashtable size is set to 0
from userspace,  hashtable will not work and panic will occur.

Fixes: 459aa660eb1d ("gtp: add initial driver for datapath of GPRS Tunneling Protocol (GTP-U)")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-04 13:41:15 +01:00
Taehee Yoo
75f08d9211 gtp: fix wrong condition in gtp_genl_dump_pdp()
[ Upstream commit 94a6d9fb88df43f92d943c32b84ce398d50bf49f ]

gtp_genl_dump_pdp() is ->dumpit() callback of GTP module and it is used
to dump pdp contexts. it would be re-executed because of dump packet size.

If dump packet size is too big, it saves current dump pointer
(gtp interface pointer, bucket, TID value) then it restarts dump from
last pointer.
Current GTP code allows adding zero TID pdp context but dump code
ignores zero TID value. So, last dump pointer will not be found.

In addition, this patch adds missing rcu_read_lock() in
gtp_genl_dump_pdp().

Fixes: 459aa660eb1d ("gtp: add initial driver for datapath of GPRS Tunneling Protocol (GTP-U)")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-04 13:41:14 +01:00
Taehee Yoo
0d1e561fc3 gtp: fix use-after-free in gtp_newlink()
[ Upstream commit a2bed90704c68d3763bf24decb1b781a45395de8 ]

Current gtp_newlink() could be called after unregister_pernet_subsys().
gtp_newlink() uses gtp_net but it can be destroyed by
unregister_pernet_subsys().
So unregister_pernet_subsys() should be called after
rtnl_link_unregister().

Test commands:
   #SHELL 1
   while :
   do
	   for i in {1..5}
	   do
		./gtp-link add gtp$i &
	   done
	   killall gtp-link
   done

   #SHELL 2
   while :
   do
	modprobe -rv gtp
   done

Splat looks like:
[  753.176631] BUG: KASAN: use-after-free in gtp_newlink+0x9b4/0xa5c [gtp]
[  753.177722] Read of size 8 at addr ffff8880d48f2458 by task gtp-link/7126
[  753.179082] CPU: 0 PID: 7126 Comm: gtp-link Tainted: G        W         5.2.0-rc6+ #50
[  753.185801] Call Trace:
[  753.186264]  dump_stack+0x7c/0xbb
[  753.186863]  ? gtp_newlink+0x9b4/0xa5c [gtp]
[  753.187583]  print_address_description+0xc7/0x240
[  753.188382]  ? gtp_newlink+0x9b4/0xa5c [gtp]
[  753.189097]  ? gtp_newlink+0x9b4/0xa5c [gtp]
[  753.189846]  __kasan_report+0x12a/0x16f
[  753.190542]  ? gtp_newlink+0x9b4/0xa5c [gtp]
[  753.191298]  kasan_report+0xe/0x20
[  753.191893]  gtp_newlink+0x9b4/0xa5c [gtp]
[  753.192580]  ? __netlink_ns_capable+0xc3/0xf0
[  753.193370]  __rtnl_newlink+0xb9f/0x11b0
[ ... ]
[  753.241201] Allocated by task 7186:
[  753.241844]  save_stack+0x19/0x80
[  753.242399]  __kasan_kmalloc.constprop.3+0xa0/0xd0
[  753.243192]  __kmalloc+0x13e/0x300
[  753.243764]  ops_init+0xd6/0x350
[  753.244314]  register_pernet_operations+0x249/0x6f0
[ ... ]
[  753.251770] Freed by task 7178:
[  753.252288]  save_stack+0x19/0x80
[  753.252833]  __kasan_slab_free+0x111/0x150
[  753.253962]  kfree+0xc7/0x280
[  753.254509]  ops_free_list.part.11+0x1c4/0x2d0
[  753.255241]  unregister_pernet_operations+0x262/0x390
[ ... ]
[  753.285883] list_add corruption. next->prev should be prev (ffff8880d48f2458), but was ffff8880d497d878. (next.
[  753.287241] ------------[ cut here ]------------
[  753.287794] kernel BUG at lib/list_debug.c:25!
[  753.288364] invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI
[  753.289099] CPU: 0 PID: 7126 Comm: gtp-link Tainted: G    B   W         5.2.0-rc6+ #50
[  753.291036] RIP: 0010:__list_add_valid+0x74/0xd0
[  753.291589] Code: 48 39 da 75 27 48 39 f5 74 36 48 39 dd 74 31 48 83 c4 08 b8 01 00 00 00 5b 5d c3 48 89 d9 48b
[  753.293779] RSP: 0018:ffff8880cae8f398 EFLAGS: 00010286
[  753.294401] RAX: 0000000000000075 RBX: ffff8880d497d878 RCX: 0000000000000000
[  753.296260] RDX: 0000000000000075 RSI: 0000000000000008 RDI: ffffed10195d1e69
[  753.297070] RBP: ffff8880cd250ae0 R08: ffffed101b4bff21 R09: ffffed101b4bff21
[  753.297899] R10: 0000000000000001 R11: ffffed101b4bff20 R12: ffff8880d497d878
[  753.298703] R13: 0000000000000000 R14: ffff8880cd250ae0 R15: ffff8880d48f2458
[  753.299564] FS:  00007f5f79805740(0000) GS:ffff8880da400000(0000) knlGS:0000000000000000
[  753.300533] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  753.301231] CR2: 00007fe8c7ef4f10 CR3: 00000000b71a6006 CR4: 00000000000606f0
[  753.302183] Call Trace:
[  753.302530]  gtp_newlink+0x5f6/0xa5c [gtp]
[  753.303037]  ? __netlink_ns_capable+0xc3/0xf0
[  753.303576]  __rtnl_newlink+0xb9f/0x11b0
[  753.304092]  ? rtnl_link_unregister+0x230/0x230

Fixes: 459aa660eb1d ("gtp: add initial driver for datapath of GPRS Tunneling Protocol (GTP-U)")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-08-04 09:33:25 +02:00
Taehee Yoo
1f9ec64e92 gtp: fix Illegal context switch in RCU read-side critical section.
[ Upstream commit 3f167e1921865b379a9becf03828e7202c7b4917 ]

ipv4_pdp_add() is called in RCU read-side critical section.
So GFP_KERNEL should not be used in the function.
This patch make ipv4_pdp_add() to use GFP_ATOMIC instead of GFP_KERNEL.

Test commands:
gtp-link add gtp1 &
gtp-tunnel add gtp1 v1 100 200 1.1.1.1 2.2.2.2

Splat looks like:
[  130.618881] =============================
[  130.626382] WARNING: suspicious RCU usage
[  130.626994] 5.2.0-rc6+ #50 Not tainted
[  130.627622] -----------------------------
[  130.628223] ./include/linux/rcupdate.h:266 Illegal context switch in RCU read-side critical section!
[  130.629684]
[  130.629684] other info that might help us debug this:
[  130.629684]
[  130.631022]
[  130.631022] rcu_scheduler_active = 2, debug_locks = 1
[  130.632136] 4 locks held by gtp-tunnel/1025:
[  130.632925]  #0: 000000002b93c8b7 (cb_lock){++++}, at: genl_rcv+0x15/0x40
[  130.634159]  #1: 00000000f17bc999 (genl_mutex){+.+.}, at: genl_rcv_msg+0xfb/0x130
[  130.635487]  #2: 00000000c644ed8e (rtnl_mutex){+.+.}, at: gtp_genl_new_pdp+0x18c/0x1150 [gtp]
[  130.636936]  #3: 0000000007a1cde7 (rcu_read_lock){....}, at: gtp_genl_new_pdp+0x187/0x1150 [gtp]
[  130.638348]
[  130.638348] stack backtrace:
[  130.639062] CPU: 1 PID: 1025 Comm: gtp-tunnel Not tainted 5.2.0-rc6+ #50
[  130.641318] Call Trace:
[  130.641707]  dump_stack+0x7c/0xbb
[  130.642252]  ___might_sleep+0x2c0/0x3b0
[  130.642862]  kmem_cache_alloc_trace+0x1cd/0x2b0
[  130.643591]  gtp_genl_new_pdp+0x6c5/0x1150 [gtp]
[  130.644371]  genl_family_rcv_msg+0x63a/0x1030
[  130.645074]  ? mutex_lock_io_nested+0x1090/0x1090
[  130.645845]  ? genl_unregister_family+0x630/0x630
[  130.646592]  ? debug_show_all_locks+0x2d0/0x2d0
[  130.647293]  ? check_flags.part.40+0x440/0x440
[  130.648099]  genl_rcv_msg+0xa3/0x130
[ ... ]

Fixes: 459aa660eb1d ("gtp: add initial driver for datapath of GPRS Tunneling Protocol (GTP-U)")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-08-04 09:33:24 +02:00
Andreas Schultz
c8d6f83d3b gtp: fix cross netns recv on gtp socket
[ Upstream commit 3ab1b469e847ba425af3c5ad5068cc94b55b38d0 ]

The use of the passed through netlink src_net to check for a
cross netns operation was wrong. Using the GTP socket and the
GTP netdevice is always correct (even if the netdev has been
moved to new netns after link creation).

Remove the now obsolete net field from gtp_dev.

Signed-off-by: Andreas Schultz <aschultz@tpip.net>
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-09 22:01:54 +01:00
Andreas Schultz
d812be8288 gtp: clear DF bit on GTP packet tx
[ Upstream commit c6ce1d08eede4c2968ed08aafa3165e8e183c5a1 ]

3GPP TS 29.281 and 3GPP TS 29.060 imply that GTP-U packets should be
sent with the DF bit cleared. For example 3GPP TS 29.060, Release 8,
Section 13.2.2:

> Backbone router: Any router in the backbone may fragment the GTP
> packet if needed, according to IPv4.

Signed-off-by: Andreas Schultz <aschultz@tpip.net>
Acked-by: Harald Welte <laforge@netfilter.org>
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-09 22:01:54 +01:00
Andreas Schultz
eb84641467 gtp: add genl family modules alias
[ Upstream commit ab729823ec16aef384f09fd2cffe0b3d3f6e6cba ]

Auto-load the module when userspace asks for the gtp netlink
family.

Signed-off-by: Andreas Schultz <aschultz@tpip.net>
Acked-by: Harald Welte <laforge@netfilter.org>
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-17 06:41:54 +02:00
Wei Yongjun
c3f3cbfbf3 gtp: remove unused including <linux/version.h>
Remove including <linux/version.h> that don't need it.

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-17 22:28:49 -07:00
Pablo Neira
27ee441a43 gtp: put back reference to netns when not required anymore
This patch fixes a netns leak.

Fixes: 93edb8c7f94f ("gtp: reload GTPv1 header after pskb_may_pull()")
Reported-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-12 12:27:15 -04:00
Pablo Neira
93edb8c7f9 gtp: reload GTPv1 header after pskb_may_pull()
The GTPv1 header flags indicate the presence of optional extensions
after this header. Refresh the pointer to the GTPv1 header as skb->head
might have be reallocated via pskb_may_pull().

Fixes: 459aa660eb1d ("gtp: add initial driver for datapath of GPRS Tunneling Protocol (GTP-U)")
Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-10 15:56:23 -04:00
Pablo Neira
459aa660eb gtp: add initial driver for datapath of GPRS Tunneling Protocol (GTP-U)
This is an initial implementation of a netdev driver for GTP datapath
(GTP-U) v0 and v1, according to the GSM TS 09.60 and 3GPP TS 29.060
standards. This tunneling protocol is used to prevent subscribers from
accessing mobile carrier core network infrastructure.

This implementation requires a GGSN userspace daemon that implements the
signaling protocol (GTP-C), such as OpenGGSN [1]. This userspace daemon
updates the PDP context database that represents active subscriber
sessions through a genetlink interface.

For more context on this tunneling protocol, you can check the slides
that were presented during the NetDev 1.1 [2].

Only IPv4 is supported at this time.

[1] http://git.osmocom.org/openggsn/
[2] http://www.netdevconf.org/1.1/proceedings/slides/schultz-welte-osmocom-gtp.pdf

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-10 12:25:04 -04:00