2 * Linux NET3: IP/IP protocol decoder modified to support
3 * virtual tunnel interface
6 * Saurabh Mohan (saurabh.mohan@vyatta.com) 05/07/2012
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * as published by the Free Software Foundation; either version
11 * 2 of the License, or (at your option) any later version.
16 This version of net/ipv4/ip_vti.c is cloned of net/ipv4/ipip.c
18 For comments look at net/ipv4/ip_gre.c --ANK
22 #include <linux/capability.h>
23 #include <linux/module.h>
24 #include <linux/types.h>
25 #include <linux/kernel.h>
26 #include <linux/uaccess.h>
27 #include <linux/skbuff.h>
28 #include <linux/netdevice.h>
30 #include <linux/tcp.h>
31 #include <linux/udp.h>
32 #include <linux/if_arp.h>
33 #include <linux/init.h>
34 #include <linux/netfilter_ipv4.h>
35 #include <linux/if_ether.h>
36 #include <linux/icmpv6.h>
41 #include <net/ip_tunnels.h>
42 #include <net/inet_ecn.h>
44 #include <net/net_namespace.h>
45 #include <net/netns/generic.h>
47 static struct rtnl_link_ops vti_link_ops __read_mostly
;
49 static unsigned int vti_net_id __read_mostly
;
50 static int vti_tunnel_init(struct net_device
*dev
);
52 static int vti_input(struct sk_buff
*skb
, int nexthdr
, __be32 spi
,
55 struct ip_tunnel
*tunnel
;
56 const struct iphdr
*iph
= ip_hdr(skb
);
57 struct net
*net
= dev_net(skb
->dev
);
58 struct ip_tunnel_net
*itn
= net_generic(net
, vti_net_id
);
60 tunnel
= ip_tunnel_lookup(itn
, skb
->dev
->ifindex
, TUNNEL_NO_KEY
,
61 iph
->saddr
, iph
->daddr
, 0);
63 if (!xfrm4_policy_check(NULL
, XFRM_POLICY_IN
, skb
))
66 XFRM_TUNNEL_SKB_CB(skb
)->tunnel
.ip4
= tunnel
;
68 return xfrm_input(skb
, nexthdr
, spi
, encap_type
);
77 static int vti_rcv(struct sk_buff
*skb
)
79 XFRM_SPI_SKB_CB(skb
)->family
= AF_INET
;
80 XFRM_SPI_SKB_CB(skb
)->daddroff
= offsetof(struct iphdr
, daddr
);
82 return vti_input(skb
, ip_hdr(skb
)->protocol
, 0, 0);
85 static int vti_rcv_cb(struct sk_buff
*skb
, int err
)
87 unsigned short family
;
88 struct net_device
*dev
;
89 struct pcpu_sw_netstats
*tstats
;
91 struct xfrm_mode
*inner_mode
;
92 struct ip_tunnel
*tunnel
= XFRM_TUNNEL_SKB_CB(skb
)->tunnel
.ip4
;
93 u32 orig_mark
= skb
->mark
;
102 dev
->stats
.rx_errors
++;
103 dev
->stats
.rx_dropped
++;
108 x
= xfrm_input_state(skb
);
110 inner_mode
= x
->inner_mode
;
112 if (x
->sel
.family
== AF_UNSPEC
) {
113 inner_mode
= xfrm_ip2inner_mode(x
, XFRM_MODE_SKB_CB(skb
)->protocol
);
114 if (inner_mode
== NULL
) {
115 XFRM_INC_STATS(dev_net(skb
->dev
),
116 LINUX_MIB_XFRMINSTATEMODEERROR
);
121 family
= inner_mode
->afinfo
->family
;
123 skb
->mark
= be32_to_cpu(tunnel
->parms
.i_key
);
124 ret
= xfrm_policy_check(NULL
, XFRM_POLICY_IN
, skb
, family
);
125 skb
->mark
= orig_mark
;
130 skb_scrub_packet(skb
, !net_eq(tunnel
->net
, dev_net(skb
->dev
)));
133 tstats
= this_cpu_ptr(dev
->tstats
);
135 u64_stats_update_begin(&tstats
->syncp
);
136 tstats
->rx_packets
++;
137 tstats
->rx_bytes
+= skb
->len
;
138 u64_stats_update_end(&tstats
->syncp
);
143 static bool vti_state_check(const struct xfrm_state
*x
, __be32 dst
, __be32 src
)
145 xfrm_address_t
*daddr
= (xfrm_address_t
*)&dst
;
146 xfrm_address_t
*saddr
= (xfrm_address_t
*)&src
;
148 /* if there is no transform then this tunnel is not functional.
149 * Or if the xfrm is not mode tunnel.
151 if (!x
|| x
->props
.mode
!= XFRM_MODE_TUNNEL
||
152 x
->props
.family
!= AF_INET
)
156 return xfrm_addr_equal(saddr
, &x
->props
.saddr
, AF_INET
);
158 if (!xfrm_state_addr_check(x
, daddr
, saddr
, AF_INET
))
164 static netdev_tx_t
vti_xmit(struct sk_buff
*skb
, struct net_device
*dev
,
167 struct ip_tunnel
*tunnel
= netdev_priv(dev
);
168 struct ip_tunnel_parm
*parms
= &tunnel
->parms
;
169 struct dst_entry
*dst
= skb_dst(skb
);
170 struct net_device
*tdev
; /* Device to other host */
175 dev
->stats
.tx_carrier_errors
++;
180 dst
= xfrm_lookup(tunnel
->net
, dst
, fl
, NULL
, 0);
182 dev
->stats
.tx_carrier_errors
++;
186 if (!vti_state_check(dst
->xfrm
, parms
->iph
.daddr
, parms
->iph
.saddr
)) {
187 dev
->stats
.tx_carrier_errors
++;
196 dev
->stats
.collisions
++;
200 if (tunnel
->err_count
> 0) {
201 if (time_before(jiffies
,
202 tunnel
->err_time
+ IPTUNNEL_ERR_TIMEO
)) {
204 dst_link_failure(skb
);
206 tunnel
->err_count
= 0;
210 if (skb
->len
> mtu
) {
211 skb_dst(skb
)->ops
->update_pmtu(skb_dst(skb
), NULL
, skb
, mtu
);
212 if (skb
->protocol
== htons(ETH_P_IP
)) {
213 icmp_send(skb
, ICMP_DEST_UNREACH
, ICMP_FRAG_NEEDED
,
216 if (mtu
< IPV6_MIN_MTU
)
219 icmpv6_send(skb
, ICMPV6_PKT_TOOBIG
, 0, mtu
);
226 skb_scrub_packet(skb
, !net_eq(tunnel
->net
, dev_net(dev
)));
227 skb_dst_set(skb
, dst
);
228 skb
->dev
= skb_dst(skb
)->dev
;
230 err
= dst_output(tunnel
->net
, skb
->sk
, skb
);
231 if (net_xmit_eval(err
) == 0)
233 iptunnel_xmit_stats(dev
, err
);
237 dst_link_failure(skb
);
239 dev
->stats
.tx_errors
++;
244 /* This function assumes it is being called from dev_queue_xmit()
245 * and that skb is filled properly by that function.
247 static netdev_tx_t
vti_tunnel_xmit(struct sk_buff
*skb
, struct net_device
*dev
)
249 struct ip_tunnel
*tunnel
= netdev_priv(dev
);
252 memset(&fl
, 0, sizeof(fl
));
254 switch (skb
->protocol
) {
255 case htons(ETH_P_IP
):
256 xfrm_decode_session(skb
, &fl
, AF_INET
);
257 memset(IPCB(skb
), 0, sizeof(*IPCB(skb
)));
259 case htons(ETH_P_IPV6
):
260 xfrm_decode_session(skb
, &fl
, AF_INET6
);
261 memset(IP6CB(skb
), 0, sizeof(*IP6CB(skb
)));
264 dev
->stats
.tx_errors
++;
269 /* override mark with tunnel output key */
270 fl
.flowi_mark
= be32_to_cpu(tunnel
->parms
.o_key
);
272 return vti_xmit(skb
, dev
, &fl
);
275 static int vti4_err(struct sk_buff
*skb
, u32 info
)
279 struct xfrm_state
*x
;
280 struct ip_tunnel
*tunnel
;
281 struct ip_esp_hdr
*esph
;
282 struct ip_auth_hdr
*ah
;
283 struct ip_comp_hdr
*ipch
;
284 struct net
*net
= dev_net(skb
->dev
);
285 const struct iphdr
*iph
= (const struct iphdr
*)skb
->data
;
286 int protocol
= iph
->protocol
;
287 struct ip_tunnel_net
*itn
= net_generic(net
, vti_net_id
);
289 tunnel
= ip_tunnel_lookup(itn
, skb
->dev
->ifindex
, TUNNEL_NO_KEY
,
290 iph
->daddr
, iph
->saddr
, 0);
294 mark
= be32_to_cpu(tunnel
->parms
.o_key
);
298 esph
= (struct ip_esp_hdr
*)(skb
->data
+(iph
->ihl
<<2));
302 ah
= (struct ip_auth_hdr
*)(skb
->data
+(iph
->ihl
<<2));
306 ipch
= (struct ip_comp_hdr
*)(skb
->data
+(iph
->ihl
<<2));
307 spi
= htonl(ntohs(ipch
->cpi
));
313 switch (icmp_hdr(skb
)->type
) {
314 case ICMP_DEST_UNREACH
:
315 if (icmp_hdr(skb
)->code
!= ICMP_FRAG_NEEDED
)
323 x
= xfrm_state_lookup(net
, mark
, (const xfrm_address_t
*)&iph
->daddr
,
324 spi
, protocol
, AF_INET
);
328 if (icmp_hdr(skb
)->type
== ICMP_DEST_UNREACH
)
329 ipv4_update_pmtu(skb
, net
, info
, 0, 0, protocol
, 0);
331 ipv4_redirect(skb
, net
, 0, 0, protocol
, 0);
338 vti_tunnel_ioctl(struct net_device
*dev
, struct ifreq
*ifr
, int cmd
)
341 struct ip_tunnel_parm p
;
343 if (copy_from_user(&p
, ifr
->ifr_ifru
.ifru_data
, sizeof(p
)))
346 if (cmd
== SIOCADDTUNNEL
|| cmd
== SIOCCHGTUNNEL
) {
347 if (p
.iph
.version
!= 4 || p
.iph
.protocol
!= IPPROTO_IPIP
||
352 if (!(p
.i_flags
& GRE_KEY
))
354 if (!(p
.o_flags
& GRE_KEY
))
357 p
.i_flags
= VTI_ISVTI
;
359 err
= ip_tunnel_ioctl(dev
, &p
, cmd
);
363 if (cmd
!= SIOCDELTUNNEL
) {
364 p
.i_flags
|= GRE_KEY
;
365 p
.o_flags
|= GRE_KEY
;
368 if (copy_to_user(ifr
->ifr_ifru
.ifru_data
, &p
, sizeof(p
)))
373 static const struct net_device_ops vti_netdev_ops
= {
374 .ndo_init
= vti_tunnel_init
,
375 .ndo_uninit
= ip_tunnel_uninit
,
376 .ndo_start_xmit
= vti_tunnel_xmit
,
377 .ndo_do_ioctl
= vti_tunnel_ioctl
,
378 .ndo_change_mtu
= ip_tunnel_change_mtu
,
379 .ndo_get_stats64
= ip_tunnel_get_stats64
,
380 .ndo_get_iflink
= ip_tunnel_get_iflink
,
383 static void vti_tunnel_setup(struct net_device
*dev
)
385 dev
->netdev_ops
= &vti_netdev_ops
;
386 dev
->type
= ARPHRD_TUNNEL
;
387 ip_tunnel_setup(dev
, vti_net_id
);
390 static int vti_tunnel_init(struct net_device
*dev
)
392 struct ip_tunnel
*tunnel
= netdev_priv(dev
);
393 struct iphdr
*iph
= &tunnel
->parms
.iph
;
395 memcpy(dev
->dev_addr
, &iph
->saddr
, 4);
396 memcpy(dev
->broadcast
, &iph
->daddr
, 4);
398 dev
->hard_header_len
= LL_MAX_HEADER
+ sizeof(struct iphdr
);
399 dev
->mtu
= ETH_DATA_LEN
;
400 dev
->flags
= IFF_NOARP
;
402 dev
->features
|= NETIF_F_LLTX
;
405 return ip_tunnel_init(dev
);
408 static void __net_init
vti_fb_tunnel_init(struct net_device
*dev
)
410 struct ip_tunnel
*tunnel
= netdev_priv(dev
);
411 struct iphdr
*iph
= &tunnel
->parms
.iph
;
414 iph
->protocol
= IPPROTO_IPIP
;
418 static struct xfrm4_protocol vti_esp4_protocol __read_mostly
= {
420 .input_handler
= vti_input
,
421 .cb_handler
= vti_rcv_cb
,
422 .err_handler
= vti4_err
,
426 static struct xfrm4_protocol vti_ah4_protocol __read_mostly
= {
428 .input_handler
= vti_input
,
429 .cb_handler
= vti_rcv_cb
,
430 .err_handler
= vti4_err
,
434 static struct xfrm4_protocol vti_ipcomp4_protocol __read_mostly
= {
436 .input_handler
= vti_input
,
437 .cb_handler
= vti_rcv_cb
,
438 .err_handler
= vti4_err
,
442 static int __net_init
vti_init_net(struct net
*net
)
445 struct ip_tunnel_net
*itn
;
447 err
= ip_tunnel_init_net(net
, vti_net_id
, &vti_link_ops
, "ip_vti0");
450 itn
= net_generic(net
, vti_net_id
);
451 vti_fb_tunnel_init(itn
->fb_tunnel_dev
);
455 static void __net_exit
vti_exit_net(struct net
*net
)
457 struct ip_tunnel_net
*itn
= net_generic(net
, vti_net_id
);
458 ip_tunnel_delete_net(itn
, &vti_link_ops
);
461 static struct pernet_operations vti_net_ops
= {
462 .init
= vti_init_net
,
463 .exit
= vti_exit_net
,
465 .size
= sizeof(struct ip_tunnel_net
),
468 static int vti_tunnel_validate(struct nlattr
*tb
[], struct nlattr
*data
[])
473 static void vti_netlink_parms(struct nlattr
*data
[],
474 struct ip_tunnel_parm
*parms
)
476 memset(parms
, 0, sizeof(*parms
));
478 parms
->iph
.protocol
= IPPROTO_IPIP
;
483 parms
->i_flags
= VTI_ISVTI
;
485 if (data
[IFLA_VTI_LINK
])
486 parms
->link
= nla_get_u32(data
[IFLA_VTI_LINK
]);
488 if (data
[IFLA_VTI_IKEY
])
489 parms
->i_key
= nla_get_be32(data
[IFLA_VTI_IKEY
]);
491 if (data
[IFLA_VTI_OKEY
])
492 parms
->o_key
= nla_get_be32(data
[IFLA_VTI_OKEY
]);
494 if (data
[IFLA_VTI_LOCAL
])
495 parms
->iph
.saddr
= nla_get_in_addr(data
[IFLA_VTI_LOCAL
]);
497 if (data
[IFLA_VTI_REMOTE
])
498 parms
->iph
.daddr
= nla_get_in_addr(data
[IFLA_VTI_REMOTE
]);
502 static int vti_newlink(struct net
*src_net
, struct net_device
*dev
,
503 struct nlattr
*tb
[], struct nlattr
*data
[])
505 struct ip_tunnel_parm parms
;
507 vti_netlink_parms(data
, &parms
);
508 return ip_tunnel_newlink(dev
, tb
, &parms
);
511 static int vti_changelink(struct net_device
*dev
, struct nlattr
*tb
[],
512 struct nlattr
*data
[])
514 struct ip_tunnel_parm p
;
516 vti_netlink_parms(data
, &p
);
517 return ip_tunnel_changelink(dev
, tb
, &p
);
520 static size_t vti_get_size(const struct net_device
*dev
)
531 /* IFLA_VTI_REMOTE */
536 static int vti_fill_info(struct sk_buff
*skb
, const struct net_device
*dev
)
538 struct ip_tunnel
*t
= netdev_priv(dev
);
539 struct ip_tunnel_parm
*p
= &t
->parms
;
541 nla_put_u32(skb
, IFLA_VTI_LINK
, p
->link
);
542 nla_put_be32(skb
, IFLA_VTI_IKEY
, p
->i_key
);
543 nla_put_be32(skb
, IFLA_VTI_OKEY
, p
->o_key
);
544 nla_put_in_addr(skb
, IFLA_VTI_LOCAL
, p
->iph
.saddr
);
545 nla_put_in_addr(skb
, IFLA_VTI_REMOTE
, p
->iph
.daddr
);
550 static const struct nla_policy vti_policy
[IFLA_VTI_MAX
+ 1] = {
551 [IFLA_VTI_LINK
] = { .type
= NLA_U32
},
552 [IFLA_VTI_IKEY
] = { .type
= NLA_U32
},
553 [IFLA_VTI_OKEY
] = { .type
= NLA_U32
},
554 [IFLA_VTI_LOCAL
] = { .len
= FIELD_SIZEOF(struct iphdr
, saddr
) },
555 [IFLA_VTI_REMOTE
] = { .len
= FIELD_SIZEOF(struct iphdr
, daddr
) },
558 static struct rtnl_link_ops vti_link_ops __read_mostly
= {
560 .maxtype
= IFLA_VTI_MAX
,
561 .policy
= vti_policy
,
562 .priv_size
= sizeof(struct ip_tunnel
),
563 .setup
= vti_tunnel_setup
,
564 .validate
= vti_tunnel_validate
,
565 .newlink
= vti_newlink
,
566 .changelink
= vti_changelink
,
567 .dellink
= ip_tunnel_dellink
,
568 .get_size
= vti_get_size
,
569 .fill_info
= vti_fill_info
,
570 .get_link_net
= ip_tunnel_get_link_net
,
573 static bool is_vti_tunnel(const struct net_device
*dev
)
575 return dev
->netdev_ops
== &vti_netdev_ops
;
578 static int vti_device_event(struct notifier_block
*unused
,
579 unsigned long event
, void *ptr
)
581 struct net_device
*dev
= netdev_notifier_info_to_dev(ptr
);
582 struct ip_tunnel
*tunnel
= netdev_priv(dev
);
584 if (!is_vti_tunnel(dev
))
589 if (!net_eq(tunnel
->net
, dev_net(dev
)))
590 xfrm_garbage_collect(tunnel
->net
);
596 static struct notifier_block vti_notifier_block __read_mostly
= {
597 .notifier_call
= vti_device_event
,
600 static int __init
vti_init(void)
605 pr_info("IPv4 over IPsec tunneling driver\n");
607 register_netdevice_notifier(&vti_notifier_block
);
609 msg
= "tunnel device";
610 err
= register_pernet_device(&vti_net_ops
);
612 goto pernet_dev_failed
;
614 msg
= "tunnel protocols";
615 err
= xfrm4_protocol_register(&vti_esp4_protocol
, IPPROTO_ESP
);
617 goto xfrm_proto_esp_failed
;
618 err
= xfrm4_protocol_register(&vti_ah4_protocol
, IPPROTO_AH
);
620 goto xfrm_proto_ah_failed
;
621 err
= xfrm4_protocol_register(&vti_ipcomp4_protocol
, IPPROTO_COMP
);
623 goto xfrm_proto_comp_failed
;
625 msg
= "netlink interface";
626 err
= rtnl_link_register(&vti_link_ops
);
628 goto rtnl_link_failed
;
633 xfrm4_protocol_deregister(&vti_ipcomp4_protocol
, IPPROTO_COMP
);
634 xfrm_proto_comp_failed
:
635 xfrm4_protocol_deregister(&vti_ah4_protocol
, IPPROTO_AH
);
636 xfrm_proto_ah_failed
:
637 xfrm4_protocol_deregister(&vti_esp4_protocol
, IPPROTO_ESP
);
638 xfrm_proto_esp_failed
:
639 unregister_pernet_device(&vti_net_ops
);
641 unregister_netdevice_notifier(&vti_notifier_block
);
642 pr_err("vti init: failed to register %s\n", msg
);
646 static void __exit
vti_fini(void)
648 rtnl_link_unregister(&vti_link_ops
);
649 xfrm4_protocol_deregister(&vti_ipcomp4_protocol
, IPPROTO_COMP
);
650 xfrm4_protocol_deregister(&vti_ah4_protocol
, IPPROTO_AH
);
651 xfrm4_protocol_deregister(&vti_esp4_protocol
, IPPROTO_ESP
);
652 unregister_pernet_device(&vti_net_ops
);
653 unregister_netdevice_notifier(&vti_notifier_block
);
656 module_init(vti_init
);
657 module_exit(vti_fini
);
658 MODULE_LICENSE("GPL");
659 MODULE_ALIAS_RTNL_LINK("vti");
660 MODULE_ALIAS_NETDEV("ip_vti0");