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 */
171 int pkt_len = skb->len;
176 dev->stats.tx_carrier_errors++;
181 dst = xfrm_lookup(tunnel->net, dst, fl, NULL, 0);
183 dev->stats.tx_carrier_errors++;
187 if (!vti_state_check(dst->xfrm, parms->iph.daddr, parms->iph.saddr)) {
188 dev->stats.tx_carrier_errors++;
197 dev->stats.collisions++;
201 if (tunnel->err_count > 0) {
202 if (time_before(jiffies,
203 tunnel->err_time + IPTUNNEL_ERR_TIMEO)) {
205 dst_link_failure(skb);
207 tunnel->err_count = 0;
211 if (skb->len > mtu) {
212 skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu);
213 if (skb->protocol == htons(ETH_P_IP)) {
214 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
217 if (mtu < IPV6_MIN_MTU)
220 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
227 skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(dev)));
228 skb_dst_set(skb, dst);
229 skb->dev = skb_dst(skb)->dev;
231 err = dst_output(tunnel->net, skb->sk, skb);
232 if (net_xmit_eval(err) == 0)
234 iptunnel_xmit_stats(dev, err);
238 dst_link_failure(skb);
240 dev->stats.tx_errors++;
245 /* This function assumes it is being called from dev_queue_xmit()
246 * and that skb is filled properly by that function.
248 static netdev_tx_t vti_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
250 struct ip_tunnel *tunnel = netdev_priv(dev);
253 memset(&fl, 0, sizeof(fl));
255 switch (skb->protocol) {
256 case htons(ETH_P_IP):
257 xfrm_decode_session(skb, &fl, AF_INET);
258 memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
260 case htons(ETH_P_IPV6):
261 xfrm_decode_session(skb, &fl, AF_INET6);
262 memset(IP6CB(skb), 0, sizeof(*IP6CB(skb)));
265 dev->stats.tx_errors++;
270 /* override mark with tunnel output key */
271 fl.flowi_mark = be32_to_cpu(tunnel->parms.o_key);
273 return vti_xmit(skb, dev, &fl);
276 static int vti4_err(struct sk_buff *skb, u32 info)
280 struct xfrm_state *x;
281 struct ip_tunnel *tunnel;
282 struct ip_esp_hdr *esph;
283 struct ip_auth_hdr *ah ;
284 struct ip_comp_hdr *ipch;
285 struct net *net = dev_net(skb->dev);
286 const struct iphdr *iph = (const struct iphdr *)skb->data;
287 int protocol = iph->protocol;
288 struct ip_tunnel_net *itn = net_generic(net, vti_net_id);
290 tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, TUNNEL_NO_KEY,
291 iph->daddr, iph->saddr, 0);
295 mark = be32_to_cpu(tunnel->parms.o_key);
299 esph = (struct ip_esp_hdr *)(skb->data+(iph->ihl<<2));
303 ah = (struct ip_auth_hdr *)(skb->data+(iph->ihl<<2));
307 ipch = (struct ip_comp_hdr *)(skb->data+(iph->ihl<<2));
308 spi = htonl(ntohs(ipch->cpi));
314 switch (icmp_hdr(skb)->type) {
315 case ICMP_DEST_UNREACH:
316 if (icmp_hdr(skb)->code != ICMP_FRAG_NEEDED)
324 x = xfrm_state_lookup(net, mark, (const xfrm_address_t *)&iph->daddr,
325 spi, protocol, AF_INET);
329 if (icmp_hdr(skb)->type == ICMP_DEST_UNREACH)
330 ipv4_update_pmtu(skb, net, info, 0, 0, protocol, 0);
332 ipv4_redirect(skb, net, 0, 0, protocol, 0);
339 vti_tunnel_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
342 struct ip_tunnel_parm p;
344 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
347 if (cmd == SIOCADDTUNNEL || cmd == SIOCCHGTUNNEL) {
348 if (p.iph.version != 4 || p.iph.protocol != IPPROTO_IPIP ||
353 if (!(p.i_flags & GRE_KEY))
355 if (!(p.o_flags & GRE_KEY))
358 p.i_flags = VTI_ISVTI;
360 err = ip_tunnel_ioctl(dev, &p, cmd);
364 if (cmd != SIOCDELTUNNEL) {
365 p.i_flags |= GRE_KEY;
366 p.o_flags |= GRE_KEY;
369 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
374 static const struct net_device_ops vti_netdev_ops = {
375 .ndo_init = vti_tunnel_init,
376 .ndo_uninit = ip_tunnel_uninit,
377 .ndo_start_xmit = vti_tunnel_xmit,
378 .ndo_do_ioctl = vti_tunnel_ioctl,
379 .ndo_change_mtu = ip_tunnel_change_mtu,
380 .ndo_get_stats64 = ip_tunnel_get_stats64,
381 .ndo_get_iflink = ip_tunnel_get_iflink,
384 static void vti_tunnel_setup(struct net_device *dev)
386 dev->netdev_ops = &vti_netdev_ops;
387 dev->type = ARPHRD_TUNNEL;
388 ip_tunnel_setup(dev, vti_net_id);
391 static int vti_tunnel_init(struct net_device *dev)
393 struct ip_tunnel *tunnel = netdev_priv(dev);
394 struct iphdr *iph = &tunnel->parms.iph;
396 memcpy(dev->dev_addr, &iph->saddr, 4);
397 memcpy(dev->broadcast, &iph->daddr, 4);
399 dev->hard_header_len = LL_MAX_HEADER + sizeof(struct iphdr);
400 dev->mtu = ETH_DATA_LEN;
401 dev->flags = IFF_NOARP;
403 dev->features |= NETIF_F_LLTX;
406 return ip_tunnel_init(dev);
409 static void __net_init vti_fb_tunnel_init(struct net_device *dev)
411 struct ip_tunnel *tunnel = netdev_priv(dev);
412 struct iphdr *iph = &tunnel->parms.iph;
415 iph->protocol = IPPROTO_IPIP;
419 static struct xfrm4_protocol vti_esp4_protocol __read_mostly = {
421 .input_handler = vti_input,
422 .cb_handler = vti_rcv_cb,
423 .err_handler = vti4_err,
427 static struct xfrm4_protocol vti_ah4_protocol __read_mostly = {
429 .input_handler = vti_input,
430 .cb_handler = vti_rcv_cb,
431 .err_handler = vti4_err,
435 static struct xfrm4_protocol vti_ipcomp4_protocol __read_mostly = {
437 .input_handler = vti_input,
438 .cb_handler = vti_rcv_cb,
439 .err_handler = vti4_err,
443 static int __net_init vti_init_net(struct net *net)
446 struct ip_tunnel_net *itn;
448 err = ip_tunnel_init_net(net, vti_net_id, &vti_link_ops, "ip_vti0");
451 itn = net_generic(net, vti_net_id);
452 vti_fb_tunnel_init(itn->fb_tunnel_dev);
456 static void __net_exit vti_exit_net(struct net *net)
458 struct ip_tunnel_net *itn = net_generic(net, vti_net_id);
459 ip_tunnel_delete_net(itn, &vti_link_ops);
462 static struct pernet_operations vti_net_ops = {
463 .init = vti_init_net,
464 .exit = vti_exit_net,
466 .size = sizeof(struct ip_tunnel_net),
469 static int vti_tunnel_validate(struct nlattr *tb[], struct nlattr *data[],
470 struct netlink_ext_ack *extack)
475 static void vti_netlink_parms(struct nlattr *data[],
476 struct ip_tunnel_parm *parms,
479 memset(parms, 0, sizeof(*parms));
481 parms->iph.protocol = IPPROTO_IPIP;
486 parms->i_flags = VTI_ISVTI;
488 if (data[IFLA_VTI_LINK])
489 parms->link = nla_get_u32(data[IFLA_VTI_LINK]);
491 if (data[IFLA_VTI_IKEY])
492 parms->i_key = nla_get_be32(data[IFLA_VTI_IKEY]);
494 if (data[IFLA_VTI_OKEY])
495 parms->o_key = nla_get_be32(data[IFLA_VTI_OKEY]);
497 if (data[IFLA_VTI_LOCAL])
498 parms->iph.saddr = nla_get_in_addr(data[IFLA_VTI_LOCAL]);
500 if (data[IFLA_VTI_REMOTE])
501 parms->iph.daddr = nla_get_in_addr(data[IFLA_VTI_REMOTE]);
503 if (data[IFLA_VTI_FWMARK])
504 *fwmark = nla_get_u32(data[IFLA_VTI_FWMARK]);
507 static int vti_newlink(struct net *src_net, struct net_device *dev,
508 struct nlattr *tb[], struct nlattr *data[],
509 struct netlink_ext_ack *extack)
511 struct ip_tunnel_parm parms;
514 vti_netlink_parms(data, &parms, &fwmark);
515 return ip_tunnel_newlink(dev, tb, &parms, fwmark);
518 static int vti_changelink(struct net_device *dev, struct nlattr *tb[],
519 struct nlattr *data[],
520 struct netlink_ext_ack *extack)
522 struct ip_tunnel *t = netdev_priv(dev);
523 __u32 fwmark = t->fwmark;
524 struct ip_tunnel_parm p;
526 vti_netlink_parms(data, &p, &fwmark);
527 return ip_tunnel_changelink(dev, tb, &p, fwmark);
530 static size_t vti_get_size(const struct net_device *dev)
541 /* IFLA_VTI_REMOTE */
543 /* IFLA_VTI_FWMARK */
548 static int vti_fill_info(struct sk_buff *skb, const struct net_device *dev)
550 struct ip_tunnel *t = netdev_priv(dev);
551 struct ip_tunnel_parm *p = &t->parms;
553 if (nla_put_u32(skb, IFLA_VTI_LINK, p->link) ||
554 nla_put_be32(skb, IFLA_VTI_IKEY, p->i_key) ||
555 nla_put_be32(skb, IFLA_VTI_OKEY, p->o_key) ||
556 nla_put_in_addr(skb, IFLA_VTI_LOCAL, p->iph.saddr) ||
557 nla_put_in_addr(skb, IFLA_VTI_REMOTE, p->iph.daddr) ||
558 nla_put_u32(skb, IFLA_VTI_FWMARK, t->fwmark))
564 static const struct nla_policy vti_policy[IFLA_VTI_MAX + 1] = {
565 [IFLA_VTI_LINK] = { .type = NLA_U32 },
566 [IFLA_VTI_IKEY] = { .type = NLA_U32 },
567 [IFLA_VTI_OKEY] = { .type = NLA_U32 },
568 [IFLA_VTI_LOCAL] = { .len = FIELD_SIZEOF(struct iphdr, saddr) },
569 [IFLA_VTI_REMOTE] = { .len = FIELD_SIZEOF(struct iphdr, daddr) },
570 [IFLA_VTI_FWMARK] = { .type = NLA_U32 },
573 static struct rtnl_link_ops vti_link_ops __read_mostly = {
575 .maxtype = IFLA_VTI_MAX,
576 .policy = vti_policy,
577 .priv_size = sizeof(struct ip_tunnel),
578 .setup = vti_tunnel_setup,
579 .validate = vti_tunnel_validate,
580 .newlink = vti_newlink,
581 .changelink = vti_changelink,
582 .dellink = ip_tunnel_dellink,
583 .get_size = vti_get_size,
584 .fill_info = vti_fill_info,
585 .get_link_net = ip_tunnel_get_link_net,
588 static int __init vti_init(void)
593 pr_info("IPv4 over IPsec tunneling driver\n");
595 msg = "tunnel device";
596 err = register_pernet_device(&vti_net_ops);
598 goto pernet_dev_failed;
600 msg = "tunnel protocols";
601 err = xfrm4_protocol_register(&vti_esp4_protocol, IPPROTO_ESP);
603 goto xfrm_proto_esp_failed;
604 err = xfrm4_protocol_register(&vti_ah4_protocol, IPPROTO_AH);
606 goto xfrm_proto_ah_failed;
607 err = xfrm4_protocol_register(&vti_ipcomp4_protocol, IPPROTO_COMP);
609 goto xfrm_proto_comp_failed;
611 msg = "netlink interface";
612 err = rtnl_link_register(&vti_link_ops);
614 goto rtnl_link_failed;
619 xfrm4_protocol_deregister(&vti_ipcomp4_protocol, IPPROTO_COMP);
620 xfrm_proto_comp_failed:
621 xfrm4_protocol_deregister(&vti_ah4_protocol, IPPROTO_AH);
622 xfrm_proto_ah_failed:
623 xfrm4_protocol_deregister(&vti_esp4_protocol, IPPROTO_ESP);
624 xfrm_proto_esp_failed:
625 unregister_pernet_device(&vti_net_ops);
627 pr_err("vti init: failed to register %s\n", msg);
631 static void __exit vti_fini(void)
633 rtnl_link_unregister(&vti_link_ops);
634 xfrm4_protocol_deregister(&vti_ipcomp4_protocol, IPPROTO_COMP);
635 xfrm4_protocol_deregister(&vti_ah4_protocol, IPPROTO_AH);
636 xfrm4_protocol_deregister(&vti_esp4_protocol, IPPROTO_ESP);
637 unregister_pernet_device(&vti_net_ops);
640 module_init(vti_init);
641 module_exit(vti_fini);
642 MODULE_LICENSE("GPL");
643 MODULE_ALIAS_RTNL_LINK("vti");
644 MODULE_ALIAS_NETDEV("ip_vti0");