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v5.14.15
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 *	Linux NET3:	IP/IP protocol decoder.
  4 *
  5 *	Authors:
  6 *		Sam Lantinga (slouken@cs.ucdavis.edu)  02/01/95
  7 *
  8 *	Fixes:
  9 *		Alan Cox	:	Merged and made usable non modular (its so tiny its silly as
 10 *					a module taking up 2 pages).
 11 *		Alan Cox	: 	Fixed bug with 1.3.18 and IPIP not working (now needs to set skb->h.iph)
 12 *					to keep ip_forward happy.
 13 *		Alan Cox	:	More fixes for 1.3.21, and firewall fix. Maybe this will work soon 8).
 14 *		Kai Schulte	:	Fixed #defines for IP_FIREWALL->FIREWALL
 15 *              David Woodhouse :       Perform some basic ICMP handling.
 16 *                                      IPIP Routing without decapsulation.
 17 *              Carlos Picoto   :       GRE over IP support
 18 *		Alexey Kuznetsov:	Reworked. Really, now it is truncated version of ipv4/ip_gre.c.
 19 *					I do not want to merge them together.
 20 */
 21
 22/* tunnel.c: an IP tunnel driver
 23
 24	The purpose of this driver is to provide an IP tunnel through
 25	which you can tunnel network traffic transparently across subnets.
 26
 27	This was written by looking at Nick Holloway's dummy driver
 28	Thanks for the great code!
 29
 30		-Sam Lantinga	(slouken@cs.ucdavis.edu)  02/01/95
 31
 32	Minor tweaks:
 33		Cleaned up the code a little and added some pre-1.3.0 tweaks.
 34		dev->hard_header/hard_header_len changed to use no headers.
 35		Comments/bracketing tweaked.
 36		Made the tunnels use dev->name not tunnel: when error reporting.
 37		Added tx_dropped stat
 38
 39		-Alan Cox	(alan@lxorguk.ukuu.org.uk) 21 March 95
 40
 41	Reworked:
 42		Changed to tunnel to destination gateway in addition to the
 43			tunnel's pointopoint address
 44		Almost completely rewritten
 45		Note:  There is currently no firewall or ICMP handling done.
 46
 47		-Sam Lantinga	(slouken@cs.ucdavis.edu) 02/13/96
 48
 49*/
 50
 51/* Things I wish I had known when writing the tunnel driver:
 52
 53	When the tunnel_xmit() function is called, the skb contains the
 54	packet to be sent (plus a great deal of extra info), and dev
 55	contains the tunnel device that _we_ are.
 56
 57	When we are passed a packet, we are expected to fill in the
 58	source address with our source IP address.
 59
 60	What is the proper way to allocate, copy and free a buffer?
 61	After you allocate it, it is a "0 length" chunk of memory
 62	starting at zero.  If you want to add headers to the buffer
 63	later, you'll have to call "skb_reserve(skb, amount)" with
 64	the amount of memory you want reserved.  Then, you call
 65	"skb_put(skb, amount)" with the amount of space you want in
 66	the buffer.  skb_put() returns a pointer to the top (#0) of
 67	that buffer.  skb->len is set to the amount of space you have
 68	"allocated" with skb_put().  You can then write up to skb->len
 69	bytes to that buffer.  If you need more, you can call skb_put()
 70	again with the additional amount of space you need.  You can
 71	find out how much more space you can allocate by calling
 72	"skb_tailroom(skb)".
 73	Now, to add header space, call "skb_push(skb, header_len)".
 74	This creates space at the beginning of the buffer and returns
 75	a pointer to this new space.  If later you need to strip a
 76	header from a buffer, call "skb_pull(skb, header_len)".
 77	skb_headroom() will return how much space is left at the top
 78	of the buffer (before the main data).  Remember, this headroom
 79	space must be reserved before the skb_put() function is called.
 80	*/
 81
 82/*
 83   This version of net/ipv4/ipip.c is cloned of net/ipv4/ip_gre.c
 84
 85   For comments look at net/ipv4/ip_gre.c --ANK
 86 */
 87
 88
 89#include <linux/capability.h>
 90#include <linux/module.h>
 91#include <linux/types.h>
 92#include <linux/kernel.h>
 93#include <linux/slab.h>
 94#include <linux/uaccess.h>
 95#include <linux/skbuff.h>
 96#include <linux/netdevice.h>
 97#include <linux/in.h>
 98#include <linux/tcp.h>
 99#include <linux/udp.h>
100#include <linux/if_arp.h>
101#include <linux/init.h>
102#include <linux/netfilter_ipv4.h>
103#include <linux/if_ether.h>
104
105#include <net/sock.h>
106#include <net/ip.h>
107#include <net/icmp.h>
108#include <net/ip_tunnels.h>
109#include <net/inet_ecn.h>
110#include <net/xfrm.h>
111#include <net/net_namespace.h>
112#include <net/netns/generic.h>
113#include <net/dst_metadata.h>
114
115static bool log_ecn_error = true;
116module_param(log_ecn_error, bool, 0644);
117MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
118
119static unsigned int ipip_net_id __read_mostly;
120
121static int ipip_tunnel_init(struct net_device *dev);
122static struct rtnl_link_ops ipip_link_ops __read_mostly;
123
124static int ipip_err(struct sk_buff *skb, u32 info)
125{
126	/* All the routers (except for Linux) return only
127	 * 8 bytes of packet payload. It means, that precise relaying of
128	 * ICMP in the real Internet is absolutely infeasible.
129	 */
130	struct net *net = dev_net(skb->dev);
131	struct ip_tunnel_net *itn = net_generic(net, ipip_net_id);
132	const struct iphdr *iph = (const struct iphdr *)skb->data;
 
133	const int type = icmp_hdr(skb)->type;
134	const int code = icmp_hdr(skb)->code;
135	struct ip_tunnel *t;
136	int err = 0;
137
138	t = ip_tunnel_lookup(itn, skb->dev->ifindex, TUNNEL_NO_KEY,
139			     iph->daddr, iph->saddr, 0);
 
 
140	if (!t) {
141		err = -ENOENT;
142		goto out;
143	}
144
145	switch (type) {
146	case ICMP_DEST_UNREACH:
147		switch (code) {
148		case ICMP_SR_FAILED:
149			/* Impossible event. */
150			goto out;
151		default:
152			/* All others are translated to HOST_UNREACH.
153			 * rfc2003 contains "deep thoughts" about NET_UNREACH,
154			 * I believe they are just ether pollution. --ANK
155			 */
156			break;
157		}
158		break;
159
160	case ICMP_TIME_EXCEEDED:
161		if (code != ICMP_EXC_TTL)
162			goto out;
163		break;
164
165	case ICMP_REDIRECT:
166		break;
167
168	default:
169		goto out;
170	}
171
172	if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) {
173		ipv4_update_pmtu(skb, net, info, t->parms.link, iph->protocol);
174		goto out;
175	}
176
177	if (type == ICMP_REDIRECT) {
178		ipv4_redirect(skb, net, t->parms.link, iph->protocol);
179		goto out;
180	}
181
182	if (t->parms.iph.daddr == 0) {
183		err = -ENOENT;
184		goto out;
185	}
186
187	if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
188		goto out;
189
190	if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO))
191		t->err_count++;
192	else
193		t->err_count = 1;
194	t->err_time = jiffies;
195
196out:
197	return err;
198}
199
200static const struct tnl_ptk_info ipip_tpi = {
201	/* no tunnel info required for ipip. */
202	.proto = htons(ETH_P_IP),
203};
204
205#if IS_ENABLED(CONFIG_MPLS)
206static const struct tnl_ptk_info mplsip_tpi = {
207	/* no tunnel info required for mplsip. */
208	.proto = htons(ETH_P_MPLS_UC),
209};
210#endif
211
212static int ipip_tunnel_rcv(struct sk_buff *skb, u8 ipproto)
213{
214	struct net *net = dev_net(skb->dev);
215	struct ip_tunnel_net *itn = net_generic(net, ipip_net_id);
 
216	struct metadata_dst *tun_dst = NULL;
217	struct ip_tunnel *tunnel;
218	const struct iphdr *iph;
219
 
 
220	iph = ip_hdr(skb);
221	tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, TUNNEL_NO_KEY,
222			iph->saddr, iph->daddr, 0);
223	if (tunnel) {
224		const struct tnl_ptk_info *tpi;
225
226		if (tunnel->parms.iph.protocol != ipproto &&
227		    tunnel->parms.iph.protocol != 0)
228			goto drop;
229
230		if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb))
231			goto drop;
232#if IS_ENABLED(CONFIG_MPLS)
233		if (ipproto == IPPROTO_MPLS)
234			tpi = &mplsip_tpi;
235		else
236#endif
237			tpi = &ipip_tpi;
238		if (iptunnel_pull_header(skb, 0, tpi->proto, false))
239			goto drop;
240		if (tunnel->collect_md) {
241			tun_dst = ip_tun_rx_dst(skb, 0, 0, 0);
 
 
242			if (!tun_dst)
243				return 0;
 
244		}
245		skb_reset_mac_header(skb);
246
247		return ip_tunnel_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
248	}
249
250	return -1;
251
252drop:
253	kfree_skb(skb);
254	return 0;
255}
256
257static int ipip_rcv(struct sk_buff *skb)
258{
259	return ipip_tunnel_rcv(skb, IPPROTO_IPIP);
260}
261
262#if IS_ENABLED(CONFIG_MPLS)
263static int mplsip_rcv(struct sk_buff *skb)
264{
265	return ipip_tunnel_rcv(skb, IPPROTO_MPLS);
266}
267#endif
268
269/*
270 *	This function assumes it is being called from dev_queue_xmit()
271 *	and that skb is filled properly by that function.
272 */
273static netdev_tx_t ipip_tunnel_xmit(struct sk_buff *skb,
274				    struct net_device *dev)
275{
276	struct ip_tunnel *tunnel = netdev_priv(dev);
277	const struct iphdr  *tiph = &tunnel->parms.iph;
278	u8 ipproto;
279
280	if (!pskb_inet_may_pull(skb))
281		goto tx_error;
282
283	switch (skb->protocol) {
284	case htons(ETH_P_IP):
285		ipproto = IPPROTO_IPIP;
286		break;
287#if IS_ENABLED(CONFIG_MPLS)
288	case htons(ETH_P_MPLS_UC):
289		ipproto = IPPROTO_MPLS;
290		break;
291#endif
292	default:
293		goto tx_error;
294	}
295
296	if (tiph->protocol != ipproto && tiph->protocol != 0)
297		goto tx_error;
298
299	if (iptunnel_handle_offloads(skb, SKB_GSO_IPXIP4))
300		goto tx_error;
301
302	skb_set_inner_ipproto(skb, ipproto);
303
304	if (tunnel->collect_md)
305		ip_md_tunnel_xmit(skb, dev, ipproto, 0);
306	else
307		ip_tunnel_xmit(skb, dev, tiph, ipproto);
308	return NETDEV_TX_OK;
309
310tx_error:
311	kfree_skb(skb);
312
313	dev->stats.tx_errors++;
314	return NETDEV_TX_OK;
315}
316
317static bool ipip_tunnel_ioctl_verify_protocol(u8 ipproto)
318{
319	switch (ipproto) {
320	case 0:
321	case IPPROTO_IPIP:
322#if IS_ENABLED(CONFIG_MPLS)
323	case IPPROTO_MPLS:
324#endif
325		return true;
326	}
327
328	return false;
329}
330
331static int
332ipip_tunnel_ctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd)
333{
334	if (cmd == SIOCADDTUNNEL || cmd == SIOCCHGTUNNEL) {
335		if (p->iph.version != 4 ||
336		    !ipip_tunnel_ioctl_verify_protocol(p->iph.protocol) ||
337		    p->iph.ihl != 5 || (p->iph.frag_off & htons(~IP_DF)))
338			return -EINVAL;
339	}
340
341	p->i_key = p->o_key = 0;
342	p->i_flags = p->o_flags = 0;
 
343	return ip_tunnel_ctl(dev, p, cmd);
344}
345
346static const struct net_device_ops ipip_netdev_ops = {
347	.ndo_init       = ipip_tunnel_init,
348	.ndo_uninit     = ip_tunnel_uninit,
349	.ndo_start_xmit	= ipip_tunnel_xmit,
350	.ndo_do_ioctl	= ip_tunnel_ioctl,
351	.ndo_change_mtu = ip_tunnel_change_mtu,
352	.ndo_get_stats64 = dev_get_tstats64,
353	.ndo_get_iflink = ip_tunnel_get_iflink,
354	.ndo_tunnel_ctl	= ipip_tunnel_ctl,
355};
356
357#define IPIP_FEATURES (NETIF_F_SG |		\
358		       NETIF_F_FRAGLIST |	\
359		       NETIF_F_HIGHDMA |	\
360		       NETIF_F_GSO_SOFTWARE |	\
361		       NETIF_F_HW_CSUM)
362
363static void ipip_tunnel_setup(struct net_device *dev)
364{
365	dev->netdev_ops		= &ipip_netdev_ops;
366	dev->header_ops		= &ip_tunnel_header_ops;
367
368	dev->type		= ARPHRD_TUNNEL;
369	dev->flags		= IFF_NOARP;
370	dev->addr_len		= 4;
371	dev->features		|= NETIF_F_LLTX;
372	netif_keep_dst(dev);
373
374	dev->features		|= IPIP_FEATURES;
375	dev->hw_features	|= IPIP_FEATURES;
376	ip_tunnel_setup(dev, ipip_net_id);
377}
378
379static int ipip_tunnel_init(struct net_device *dev)
380{
381	struct ip_tunnel *tunnel = netdev_priv(dev);
382
383	memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4);
384	memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4);
385
386	tunnel->tun_hlen = 0;
387	tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen;
388	return ip_tunnel_init(dev);
389}
390
391static int ipip_tunnel_validate(struct nlattr *tb[], struct nlattr *data[],
392				struct netlink_ext_ack *extack)
393{
394	u8 proto;
395
396	if (!data || !data[IFLA_IPTUN_PROTO])
397		return 0;
398
399	proto = nla_get_u8(data[IFLA_IPTUN_PROTO]);
400	if (proto != IPPROTO_IPIP && proto != IPPROTO_MPLS && proto != 0)
401		return -EINVAL;
402
403	return 0;
404}
405
406static void ipip_netlink_parms(struct nlattr *data[],
407			       struct ip_tunnel_parm *parms, bool *collect_md,
408			       __u32 *fwmark)
409{
410	memset(parms, 0, sizeof(*parms));
411
412	parms->iph.version = 4;
413	parms->iph.protocol = IPPROTO_IPIP;
414	parms->iph.ihl = 5;
415	*collect_md = false;
416
417	if (!data)
418		return;
419
420	if (data[IFLA_IPTUN_LINK])
421		parms->link = nla_get_u32(data[IFLA_IPTUN_LINK]);
422
423	if (data[IFLA_IPTUN_LOCAL])
424		parms->iph.saddr = nla_get_in_addr(data[IFLA_IPTUN_LOCAL]);
425
426	if (data[IFLA_IPTUN_REMOTE])
427		parms->iph.daddr = nla_get_in_addr(data[IFLA_IPTUN_REMOTE]);
428
429	if (data[IFLA_IPTUN_TTL]) {
430		parms->iph.ttl = nla_get_u8(data[IFLA_IPTUN_TTL]);
431		if (parms->iph.ttl)
432			parms->iph.frag_off = htons(IP_DF);
433	}
434
435	if (data[IFLA_IPTUN_TOS])
436		parms->iph.tos = nla_get_u8(data[IFLA_IPTUN_TOS]);
437
438	if (data[IFLA_IPTUN_PROTO])
439		parms->iph.protocol = nla_get_u8(data[IFLA_IPTUN_PROTO]);
440
441	if (!data[IFLA_IPTUN_PMTUDISC] || nla_get_u8(data[IFLA_IPTUN_PMTUDISC]))
442		parms->iph.frag_off = htons(IP_DF);
443
444	if (data[IFLA_IPTUN_COLLECT_METADATA])
445		*collect_md = true;
446
447	if (data[IFLA_IPTUN_FWMARK])
448		*fwmark = nla_get_u32(data[IFLA_IPTUN_FWMARK]);
449}
450
451/* This function returns true when ENCAP attributes are present in the nl msg */
452static bool ipip_netlink_encap_parms(struct nlattr *data[],
453				     struct ip_tunnel_encap *ipencap)
454{
455	bool ret = false;
456
457	memset(ipencap, 0, sizeof(*ipencap));
458
459	if (!data)
460		return ret;
461
462	if (data[IFLA_IPTUN_ENCAP_TYPE]) {
463		ret = true;
464		ipencap->type = nla_get_u16(data[IFLA_IPTUN_ENCAP_TYPE]);
465	}
466
467	if (data[IFLA_IPTUN_ENCAP_FLAGS]) {
468		ret = true;
469		ipencap->flags = nla_get_u16(data[IFLA_IPTUN_ENCAP_FLAGS]);
470	}
471
472	if (data[IFLA_IPTUN_ENCAP_SPORT]) {
473		ret = true;
474		ipencap->sport = nla_get_be16(data[IFLA_IPTUN_ENCAP_SPORT]);
475	}
476
477	if (data[IFLA_IPTUN_ENCAP_DPORT]) {
478		ret = true;
479		ipencap->dport = nla_get_be16(data[IFLA_IPTUN_ENCAP_DPORT]);
480	}
481
482	return ret;
483}
484
485static int ipip_newlink(struct net *src_net, struct net_device *dev,
486			struct nlattr *tb[], struct nlattr *data[],
487			struct netlink_ext_ack *extack)
488{
489	struct ip_tunnel *t = netdev_priv(dev);
490	struct ip_tunnel_parm p;
491	struct ip_tunnel_encap ipencap;
 
492	__u32 fwmark = 0;
493
494	if (ipip_netlink_encap_parms(data, &ipencap)) {
495		int err = ip_tunnel_encap_setup(t, &ipencap);
496
497		if (err < 0)
498			return err;
499	}
500
501	ipip_netlink_parms(data, &p, &t->collect_md, &fwmark);
502	return ip_tunnel_newlink(dev, tb, &p, fwmark);
503}
504
505static int ipip_changelink(struct net_device *dev, struct nlattr *tb[],
506			   struct nlattr *data[],
507			   struct netlink_ext_ack *extack)
508{
509	struct ip_tunnel *t = netdev_priv(dev);
510	struct ip_tunnel_parm p;
511	struct ip_tunnel_encap ipencap;
 
512	bool collect_md;
513	__u32 fwmark = t->fwmark;
514
515	if (ipip_netlink_encap_parms(data, &ipencap)) {
516		int err = ip_tunnel_encap_setup(t, &ipencap);
517
518		if (err < 0)
519			return err;
520	}
521
522	ipip_netlink_parms(data, &p, &collect_md, &fwmark);
523	if (collect_md)
524		return -EINVAL;
525
526	if (((dev->flags & IFF_POINTOPOINT) && !p.iph.daddr) ||
527	    (!(dev->flags & IFF_POINTOPOINT) && p.iph.daddr))
528		return -EINVAL;
529
530	return ip_tunnel_changelink(dev, tb, &p, fwmark);
531}
532
533static size_t ipip_get_size(const struct net_device *dev)
534{
535	return
536		/* IFLA_IPTUN_LINK */
537		nla_total_size(4) +
538		/* IFLA_IPTUN_LOCAL */
539		nla_total_size(4) +
540		/* IFLA_IPTUN_REMOTE */
541		nla_total_size(4) +
542		/* IFLA_IPTUN_TTL */
543		nla_total_size(1) +
544		/* IFLA_IPTUN_TOS */
545		nla_total_size(1) +
546		/* IFLA_IPTUN_PROTO */
547		nla_total_size(1) +
548		/* IFLA_IPTUN_PMTUDISC */
549		nla_total_size(1) +
550		/* IFLA_IPTUN_ENCAP_TYPE */
551		nla_total_size(2) +
552		/* IFLA_IPTUN_ENCAP_FLAGS */
553		nla_total_size(2) +
554		/* IFLA_IPTUN_ENCAP_SPORT */
555		nla_total_size(2) +
556		/* IFLA_IPTUN_ENCAP_DPORT */
557		nla_total_size(2) +
558		/* IFLA_IPTUN_COLLECT_METADATA */
559		nla_total_size(0) +
560		/* IFLA_IPTUN_FWMARK */
561		nla_total_size(4) +
562		0;
563}
564
565static int ipip_fill_info(struct sk_buff *skb, const struct net_device *dev)
566{
567	struct ip_tunnel *tunnel = netdev_priv(dev);
568	struct ip_tunnel_parm *parm = &tunnel->parms;
569
570	if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) ||
571	    nla_put_in_addr(skb, IFLA_IPTUN_LOCAL, parm->iph.saddr) ||
572	    nla_put_in_addr(skb, IFLA_IPTUN_REMOTE, parm->iph.daddr) ||
573	    nla_put_u8(skb, IFLA_IPTUN_TTL, parm->iph.ttl) ||
574	    nla_put_u8(skb, IFLA_IPTUN_TOS, parm->iph.tos) ||
575	    nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->iph.protocol) ||
576	    nla_put_u8(skb, IFLA_IPTUN_PMTUDISC,
577		       !!(parm->iph.frag_off & htons(IP_DF))) ||
578	    nla_put_u32(skb, IFLA_IPTUN_FWMARK, tunnel->fwmark))
579		goto nla_put_failure;
580
581	if (nla_put_u16(skb, IFLA_IPTUN_ENCAP_TYPE,
582			tunnel->encap.type) ||
583	    nla_put_be16(skb, IFLA_IPTUN_ENCAP_SPORT,
584			 tunnel->encap.sport) ||
585	    nla_put_be16(skb, IFLA_IPTUN_ENCAP_DPORT,
586			 tunnel->encap.dport) ||
587	    nla_put_u16(skb, IFLA_IPTUN_ENCAP_FLAGS,
588			tunnel->encap.flags))
589		goto nla_put_failure;
590
591	if (tunnel->collect_md)
592		if (nla_put_flag(skb, IFLA_IPTUN_COLLECT_METADATA))
593			goto nla_put_failure;
594	return 0;
595
596nla_put_failure:
597	return -EMSGSIZE;
598}
599
600static const struct nla_policy ipip_policy[IFLA_IPTUN_MAX + 1] = {
601	[IFLA_IPTUN_LINK]		= { .type = NLA_U32 },
602	[IFLA_IPTUN_LOCAL]		= { .type = NLA_U32 },
603	[IFLA_IPTUN_REMOTE]		= { .type = NLA_U32 },
604	[IFLA_IPTUN_TTL]		= { .type = NLA_U8 },
605	[IFLA_IPTUN_TOS]		= { .type = NLA_U8 },
606	[IFLA_IPTUN_PROTO]		= { .type = NLA_U8 },
607	[IFLA_IPTUN_PMTUDISC]		= { .type = NLA_U8 },
608	[IFLA_IPTUN_ENCAP_TYPE]		= { .type = NLA_U16 },
609	[IFLA_IPTUN_ENCAP_FLAGS]	= { .type = NLA_U16 },
610	[IFLA_IPTUN_ENCAP_SPORT]	= { .type = NLA_U16 },
611	[IFLA_IPTUN_ENCAP_DPORT]	= { .type = NLA_U16 },
612	[IFLA_IPTUN_COLLECT_METADATA]	= { .type = NLA_FLAG },
613	[IFLA_IPTUN_FWMARK]		= { .type = NLA_U32 },
614};
615
616static struct rtnl_link_ops ipip_link_ops __read_mostly = {
617	.kind		= "ipip",
618	.maxtype	= IFLA_IPTUN_MAX,
619	.policy		= ipip_policy,
620	.priv_size	= sizeof(struct ip_tunnel),
621	.setup		= ipip_tunnel_setup,
622	.validate	= ipip_tunnel_validate,
623	.newlink	= ipip_newlink,
624	.changelink	= ipip_changelink,
625	.dellink	= ip_tunnel_dellink,
626	.get_size	= ipip_get_size,
627	.fill_info	= ipip_fill_info,
628	.get_link_net	= ip_tunnel_get_link_net,
629};
630
631static struct xfrm_tunnel ipip_handler __read_mostly = {
632	.handler	=	ipip_rcv,
633	.err_handler	=	ipip_err,
634	.priority	=	1,
635};
636
637#if IS_ENABLED(CONFIG_MPLS)
638static struct xfrm_tunnel mplsip_handler __read_mostly = {
639	.handler	=	mplsip_rcv,
640	.err_handler	=	ipip_err,
641	.priority	=	1,
642};
643#endif
644
645static int __net_init ipip_init_net(struct net *net)
646{
647	return ip_tunnel_init_net(net, ipip_net_id, &ipip_link_ops, "tunl0");
648}
649
650static void __net_exit ipip_exit_batch_net(struct list_head *list_net)
 
651{
652	ip_tunnel_delete_nets(list_net, ipip_net_id, &ipip_link_ops);
 
653}
654
655static struct pernet_operations ipip_net_ops = {
656	.init = ipip_init_net,
657	.exit_batch = ipip_exit_batch_net,
658	.id   = &ipip_net_id,
659	.size = sizeof(struct ip_tunnel_net),
660};
661
662static int __init ipip_init(void)
663{
664	int err;
665
666	pr_info("ipip: IPv4 and MPLS over IPv4 tunneling driver\n");
667
668	err = register_pernet_device(&ipip_net_ops);
669	if (err < 0)
670		return err;
671	err = xfrm4_tunnel_register(&ipip_handler, AF_INET);
672	if (err < 0) {
673		pr_info("%s: can't register tunnel\n", __func__);
674		goto xfrm_tunnel_ipip_failed;
675	}
676#if IS_ENABLED(CONFIG_MPLS)
677	err = xfrm4_tunnel_register(&mplsip_handler, AF_MPLS);
678	if (err < 0) {
679		pr_info("%s: can't register tunnel\n", __func__);
680		goto xfrm_tunnel_mplsip_failed;
681	}
682#endif
683	err = rtnl_link_register(&ipip_link_ops);
684	if (err < 0)
685		goto rtnl_link_failed;
686
687out:
688	return err;
689
690rtnl_link_failed:
691#if IS_ENABLED(CONFIG_MPLS)
692	xfrm4_tunnel_deregister(&mplsip_handler, AF_MPLS);
693xfrm_tunnel_mplsip_failed:
694
695#endif
696	xfrm4_tunnel_deregister(&ipip_handler, AF_INET);
697xfrm_tunnel_ipip_failed:
698	unregister_pernet_device(&ipip_net_ops);
699	goto out;
700}
701
702static void __exit ipip_fini(void)
703{
704	rtnl_link_unregister(&ipip_link_ops);
705	if (xfrm4_tunnel_deregister(&ipip_handler, AF_INET))
706		pr_info("%s: can't deregister tunnel\n", __func__);
707#if IS_ENABLED(CONFIG_MPLS)
708	if (xfrm4_tunnel_deregister(&mplsip_handler, AF_MPLS))
709		pr_info("%s: can't deregister tunnel\n", __func__);
710#endif
711	unregister_pernet_device(&ipip_net_ops);
712}
713
714module_init(ipip_init);
715module_exit(ipip_fini);
 
716MODULE_LICENSE("GPL");
717MODULE_ALIAS_RTNL_LINK("ipip");
718MODULE_ALIAS_NETDEV("tunl0");
v6.13.7
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 *	Linux NET3:	IP/IP protocol decoder.
  4 *
  5 *	Authors:
  6 *		Sam Lantinga (slouken@cs.ucdavis.edu)  02/01/95
  7 *
  8 *	Fixes:
  9 *		Alan Cox	:	Merged and made usable non modular (its so tiny its silly as
 10 *					a module taking up 2 pages).
 11 *		Alan Cox	: 	Fixed bug with 1.3.18 and IPIP not working (now needs to set skb->h.iph)
 12 *					to keep ip_forward happy.
 13 *		Alan Cox	:	More fixes for 1.3.21, and firewall fix. Maybe this will work soon 8).
 14 *		Kai Schulte	:	Fixed #defines for IP_FIREWALL->FIREWALL
 15 *              David Woodhouse :       Perform some basic ICMP handling.
 16 *                                      IPIP Routing without decapsulation.
 17 *              Carlos Picoto   :       GRE over IP support
 18 *		Alexey Kuznetsov:	Reworked. Really, now it is truncated version of ipv4/ip_gre.c.
 19 *					I do not want to merge them together.
 20 */
 21
 22/* tunnel.c: an IP tunnel driver
 23
 24	The purpose of this driver is to provide an IP tunnel through
 25	which you can tunnel network traffic transparently across subnets.
 26
 27	This was written by looking at Nick Holloway's dummy driver
 28	Thanks for the great code!
 29
 30		-Sam Lantinga	(slouken@cs.ucdavis.edu)  02/01/95
 31
 32	Minor tweaks:
 33		Cleaned up the code a little and added some pre-1.3.0 tweaks.
 34		dev->hard_header/hard_header_len changed to use no headers.
 35		Comments/bracketing tweaked.
 36		Made the tunnels use dev->name not tunnel: when error reporting.
 37		Added tx_dropped stat
 38
 39		-Alan Cox	(alan@lxorguk.ukuu.org.uk) 21 March 95
 40
 41	Reworked:
 42		Changed to tunnel to destination gateway in addition to the
 43			tunnel's pointopoint address
 44		Almost completely rewritten
 45		Note:  There is currently no firewall or ICMP handling done.
 46
 47		-Sam Lantinga	(slouken@cs.ucdavis.edu) 02/13/96
 48
 49*/
 50
 51/* Things I wish I had known when writing the tunnel driver:
 52
 53	When the tunnel_xmit() function is called, the skb contains the
 54	packet to be sent (plus a great deal of extra info), and dev
 55	contains the tunnel device that _we_ are.
 56
 57	When we are passed a packet, we are expected to fill in the
 58	source address with our source IP address.
 59
 60	What is the proper way to allocate, copy and free a buffer?
 61	After you allocate it, it is a "0 length" chunk of memory
 62	starting at zero.  If you want to add headers to the buffer
 63	later, you'll have to call "skb_reserve(skb, amount)" with
 64	the amount of memory you want reserved.  Then, you call
 65	"skb_put(skb, amount)" with the amount of space you want in
 66	the buffer.  skb_put() returns a pointer to the top (#0) of
 67	that buffer.  skb->len is set to the amount of space you have
 68	"allocated" with skb_put().  You can then write up to skb->len
 69	bytes to that buffer.  If you need more, you can call skb_put()
 70	again with the additional amount of space you need.  You can
 71	find out how much more space you can allocate by calling
 72	"skb_tailroom(skb)".
 73	Now, to add header space, call "skb_push(skb, header_len)".
 74	This creates space at the beginning of the buffer and returns
 75	a pointer to this new space.  If later you need to strip a
 76	header from a buffer, call "skb_pull(skb, header_len)".
 77	skb_headroom() will return how much space is left at the top
 78	of the buffer (before the main data).  Remember, this headroom
 79	space must be reserved before the skb_put() function is called.
 80	*/
 81
 82/*
 83   This version of net/ipv4/ipip.c is cloned of net/ipv4/ip_gre.c
 84
 85   For comments look at net/ipv4/ip_gre.c --ANK
 86 */
 87
 88
 89#include <linux/capability.h>
 90#include <linux/module.h>
 91#include <linux/types.h>
 92#include <linux/kernel.h>
 93#include <linux/slab.h>
 94#include <linux/uaccess.h>
 95#include <linux/skbuff.h>
 96#include <linux/netdevice.h>
 97#include <linux/in.h>
 98#include <linux/tcp.h>
 99#include <linux/udp.h>
100#include <linux/if_arp.h>
101#include <linux/init.h>
102#include <linux/netfilter_ipv4.h>
103#include <linux/if_ether.h>
104
105#include <net/sock.h>
106#include <net/ip.h>
107#include <net/icmp.h>
108#include <net/ip_tunnels.h>
109#include <net/inet_ecn.h>
110#include <net/xfrm.h>
111#include <net/net_namespace.h>
112#include <net/netns/generic.h>
113#include <net/dst_metadata.h>
114
115static bool log_ecn_error = true;
116module_param(log_ecn_error, bool, 0644);
117MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
118
119static unsigned int ipip_net_id __read_mostly;
120
121static int ipip_tunnel_init(struct net_device *dev);
122static struct rtnl_link_ops ipip_link_ops __read_mostly;
123
124static int ipip_err(struct sk_buff *skb, u32 info)
125{
126	/* All the routers (except for Linux) return only
127	 * 8 bytes of packet payload. It means, that precise relaying of
128	 * ICMP in the real Internet is absolutely infeasible.
129	 */
130	struct net *net = dev_net(skb->dev);
131	struct ip_tunnel_net *itn = net_generic(net, ipip_net_id);
132	const struct iphdr *iph = (const struct iphdr *)skb->data;
133	IP_TUNNEL_DECLARE_FLAGS(flags) = { };
134	const int type = icmp_hdr(skb)->type;
135	const int code = icmp_hdr(skb)->code;
136	struct ip_tunnel *t;
137	int err = 0;
138
139	__set_bit(IP_TUNNEL_NO_KEY_BIT, flags);
140
141	t = ip_tunnel_lookup(itn, skb->dev->ifindex, flags, iph->daddr,
142			     iph->saddr, 0);
143	if (!t) {
144		err = -ENOENT;
145		goto out;
146	}
147
148	switch (type) {
149	case ICMP_DEST_UNREACH:
150		switch (code) {
151		case ICMP_SR_FAILED:
152			/* Impossible event. */
153			goto out;
154		default:
155			/* All others are translated to HOST_UNREACH.
156			 * rfc2003 contains "deep thoughts" about NET_UNREACH,
157			 * I believe they are just ether pollution. --ANK
158			 */
159			break;
160		}
161		break;
162
163	case ICMP_TIME_EXCEEDED:
164		if (code != ICMP_EXC_TTL)
165			goto out;
166		break;
167
168	case ICMP_REDIRECT:
169		break;
170
171	default:
172		goto out;
173	}
174
175	if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) {
176		ipv4_update_pmtu(skb, net, info, t->parms.link, iph->protocol);
177		goto out;
178	}
179
180	if (type == ICMP_REDIRECT) {
181		ipv4_redirect(skb, net, t->parms.link, iph->protocol);
182		goto out;
183	}
184
185	if (t->parms.iph.daddr == 0) {
186		err = -ENOENT;
187		goto out;
188	}
189
190	if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
191		goto out;
192
193	if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO))
194		t->err_count++;
195	else
196		t->err_count = 1;
197	t->err_time = jiffies;
198
199out:
200	return err;
201}
202
203static const struct tnl_ptk_info ipip_tpi = {
204	/* no tunnel info required for ipip. */
205	.proto = htons(ETH_P_IP),
206};
207
208#if IS_ENABLED(CONFIG_MPLS)
209static const struct tnl_ptk_info mplsip_tpi = {
210	/* no tunnel info required for mplsip. */
211	.proto = htons(ETH_P_MPLS_UC),
212};
213#endif
214
215static int ipip_tunnel_rcv(struct sk_buff *skb, u8 ipproto)
216{
217	struct net *net = dev_net(skb->dev);
218	struct ip_tunnel_net *itn = net_generic(net, ipip_net_id);
219	IP_TUNNEL_DECLARE_FLAGS(flags) = { };
220	struct metadata_dst *tun_dst = NULL;
221	struct ip_tunnel *tunnel;
222	const struct iphdr *iph;
223
224	__set_bit(IP_TUNNEL_NO_KEY_BIT, flags);
225
226	iph = ip_hdr(skb);
227	tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, flags, iph->saddr,
228				  iph->daddr, 0);
229	if (tunnel) {
230		const struct tnl_ptk_info *tpi;
231
232		if (tunnel->parms.iph.protocol != ipproto &&
233		    tunnel->parms.iph.protocol != 0)
234			goto drop;
235
236		if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb))
237			goto drop;
238#if IS_ENABLED(CONFIG_MPLS)
239		if (ipproto == IPPROTO_MPLS)
240			tpi = &mplsip_tpi;
241		else
242#endif
243			tpi = &ipip_tpi;
244		if (iptunnel_pull_header(skb, 0, tpi->proto, false))
245			goto drop;
246		if (tunnel->collect_md) {
247			ip_tunnel_flags_zero(flags);
248
249			tun_dst = ip_tun_rx_dst(skb, flags, 0, 0);
250			if (!tun_dst)
251				return 0;
252			ip_tunnel_md_udp_encap(skb, &tun_dst->u.tun_info);
253		}
254		skb_reset_mac_header(skb);
255
256		return ip_tunnel_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
257	}
258
259	return -1;
260
261drop:
262	kfree_skb(skb);
263	return 0;
264}
265
266static int ipip_rcv(struct sk_buff *skb)
267{
268	return ipip_tunnel_rcv(skb, IPPROTO_IPIP);
269}
270
271#if IS_ENABLED(CONFIG_MPLS)
272static int mplsip_rcv(struct sk_buff *skb)
273{
274	return ipip_tunnel_rcv(skb, IPPROTO_MPLS);
275}
276#endif
277
278/*
279 *	This function assumes it is being called from dev_queue_xmit()
280 *	and that skb is filled properly by that function.
281 */
282static netdev_tx_t ipip_tunnel_xmit(struct sk_buff *skb,
283				    struct net_device *dev)
284{
285	struct ip_tunnel *tunnel = netdev_priv(dev);
286	const struct iphdr  *tiph = &tunnel->parms.iph;
287	u8 ipproto;
288
289	if (!pskb_inet_may_pull(skb))
290		goto tx_error;
291
292	switch (skb->protocol) {
293	case htons(ETH_P_IP):
294		ipproto = IPPROTO_IPIP;
295		break;
296#if IS_ENABLED(CONFIG_MPLS)
297	case htons(ETH_P_MPLS_UC):
298		ipproto = IPPROTO_MPLS;
299		break;
300#endif
301	default:
302		goto tx_error;
303	}
304
305	if (tiph->protocol != ipproto && tiph->protocol != 0)
306		goto tx_error;
307
308	if (iptunnel_handle_offloads(skb, SKB_GSO_IPXIP4))
309		goto tx_error;
310
311	skb_set_inner_ipproto(skb, ipproto);
312
313	if (tunnel->collect_md)
314		ip_md_tunnel_xmit(skb, dev, ipproto, 0);
315	else
316		ip_tunnel_xmit(skb, dev, tiph, ipproto);
317	return NETDEV_TX_OK;
318
319tx_error:
320	kfree_skb(skb);
321
322	DEV_STATS_INC(dev, tx_errors);
323	return NETDEV_TX_OK;
324}
325
326static bool ipip_tunnel_ioctl_verify_protocol(u8 ipproto)
327{
328	switch (ipproto) {
329	case 0:
330	case IPPROTO_IPIP:
331#if IS_ENABLED(CONFIG_MPLS)
332	case IPPROTO_MPLS:
333#endif
334		return true;
335	}
336
337	return false;
338}
339
340static int
341ipip_tunnel_ctl(struct net_device *dev, struct ip_tunnel_parm_kern *p, int cmd)
342{
343	if (cmd == SIOCADDTUNNEL || cmd == SIOCCHGTUNNEL) {
344		if (p->iph.version != 4 ||
345		    !ipip_tunnel_ioctl_verify_protocol(p->iph.protocol) ||
346		    p->iph.ihl != 5 || (p->iph.frag_off & htons(~IP_DF)))
347			return -EINVAL;
348	}
349
350	p->i_key = p->o_key = 0;
351	ip_tunnel_flags_zero(p->i_flags);
352	ip_tunnel_flags_zero(p->o_flags);
353	return ip_tunnel_ctl(dev, p, cmd);
354}
355
356static const struct net_device_ops ipip_netdev_ops = {
357	.ndo_init       = ipip_tunnel_init,
358	.ndo_uninit     = ip_tunnel_uninit,
359	.ndo_start_xmit	= ipip_tunnel_xmit,
360	.ndo_siocdevprivate = ip_tunnel_siocdevprivate,
361	.ndo_change_mtu = ip_tunnel_change_mtu,
362	.ndo_get_stats64 = dev_get_tstats64,
363	.ndo_get_iflink = ip_tunnel_get_iflink,
364	.ndo_tunnel_ctl	= ipip_tunnel_ctl,
365};
366
367#define IPIP_FEATURES (NETIF_F_SG |		\
368		       NETIF_F_FRAGLIST |	\
369		       NETIF_F_HIGHDMA |	\
370		       NETIF_F_GSO_SOFTWARE |	\
371		       NETIF_F_HW_CSUM)
372
373static void ipip_tunnel_setup(struct net_device *dev)
374{
375	dev->netdev_ops		= &ipip_netdev_ops;
376	dev->header_ops		= &ip_tunnel_header_ops;
377
378	dev->type		= ARPHRD_TUNNEL;
379	dev->flags		= IFF_NOARP;
380	dev->addr_len		= 4;
381	dev->lltx		= true;
382	netif_keep_dst(dev);
383
384	dev->features		|= IPIP_FEATURES;
385	dev->hw_features	|= IPIP_FEATURES;
386	ip_tunnel_setup(dev, ipip_net_id);
387}
388
389static int ipip_tunnel_init(struct net_device *dev)
390{
391	struct ip_tunnel *tunnel = netdev_priv(dev);
392
393	__dev_addr_set(dev, &tunnel->parms.iph.saddr, 4);
394	memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4);
395
396	tunnel->tun_hlen = 0;
397	tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen;
398	return ip_tunnel_init(dev);
399}
400
401static int ipip_tunnel_validate(struct nlattr *tb[], struct nlattr *data[],
402				struct netlink_ext_ack *extack)
403{
404	u8 proto;
405
406	if (!data || !data[IFLA_IPTUN_PROTO])
407		return 0;
408
409	proto = nla_get_u8(data[IFLA_IPTUN_PROTO]);
410	if (proto != IPPROTO_IPIP && proto != IPPROTO_MPLS && proto != 0)
411		return -EINVAL;
412
413	return 0;
414}
415
416static void ipip_netlink_parms(struct nlattr *data[],
417			       struct ip_tunnel_parm_kern *parms,
418			       bool *collect_md, __u32 *fwmark)
419{
420	memset(parms, 0, sizeof(*parms));
421
422	parms->iph.version = 4;
423	parms->iph.protocol = IPPROTO_IPIP;
424	parms->iph.ihl = 5;
425	*collect_md = false;
426
427	if (!data)
428		return;
429
430	ip_tunnel_netlink_parms(data, parms);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
431
432	if (data[IFLA_IPTUN_COLLECT_METADATA])
433		*collect_md = true;
434
435	if (data[IFLA_IPTUN_FWMARK])
436		*fwmark = nla_get_u32(data[IFLA_IPTUN_FWMARK]);
437}
438
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
439static int ipip_newlink(struct net *src_net, struct net_device *dev,
440			struct nlattr *tb[], struct nlattr *data[],
441			struct netlink_ext_ack *extack)
442{
443	struct ip_tunnel *t = netdev_priv(dev);
 
444	struct ip_tunnel_encap ipencap;
445	struct ip_tunnel_parm_kern p;
446	__u32 fwmark = 0;
447
448	if (ip_tunnel_netlink_encap_parms(data, &ipencap)) {
449		int err = ip_tunnel_encap_setup(t, &ipencap);
450
451		if (err < 0)
452			return err;
453	}
454
455	ipip_netlink_parms(data, &p, &t->collect_md, &fwmark);
456	return ip_tunnel_newlink(dev, tb, &p, fwmark);
457}
458
459static int ipip_changelink(struct net_device *dev, struct nlattr *tb[],
460			   struct nlattr *data[],
461			   struct netlink_ext_ack *extack)
462{
463	struct ip_tunnel *t = netdev_priv(dev);
 
464	struct ip_tunnel_encap ipencap;
465	struct ip_tunnel_parm_kern p;
466	bool collect_md;
467	__u32 fwmark = t->fwmark;
468
469	if (ip_tunnel_netlink_encap_parms(data, &ipencap)) {
470		int err = ip_tunnel_encap_setup(t, &ipencap);
471
472		if (err < 0)
473			return err;
474	}
475
476	ipip_netlink_parms(data, &p, &collect_md, &fwmark);
477	if (collect_md)
478		return -EINVAL;
479
480	if (((dev->flags & IFF_POINTOPOINT) && !p.iph.daddr) ||
481	    (!(dev->flags & IFF_POINTOPOINT) && p.iph.daddr))
482		return -EINVAL;
483
484	return ip_tunnel_changelink(dev, tb, &p, fwmark);
485}
486
487static size_t ipip_get_size(const struct net_device *dev)
488{
489	return
490		/* IFLA_IPTUN_LINK */
491		nla_total_size(4) +
492		/* IFLA_IPTUN_LOCAL */
493		nla_total_size(4) +
494		/* IFLA_IPTUN_REMOTE */
495		nla_total_size(4) +
496		/* IFLA_IPTUN_TTL */
497		nla_total_size(1) +
498		/* IFLA_IPTUN_TOS */
499		nla_total_size(1) +
500		/* IFLA_IPTUN_PROTO */
501		nla_total_size(1) +
502		/* IFLA_IPTUN_PMTUDISC */
503		nla_total_size(1) +
504		/* IFLA_IPTUN_ENCAP_TYPE */
505		nla_total_size(2) +
506		/* IFLA_IPTUN_ENCAP_FLAGS */
507		nla_total_size(2) +
508		/* IFLA_IPTUN_ENCAP_SPORT */
509		nla_total_size(2) +
510		/* IFLA_IPTUN_ENCAP_DPORT */
511		nla_total_size(2) +
512		/* IFLA_IPTUN_COLLECT_METADATA */
513		nla_total_size(0) +
514		/* IFLA_IPTUN_FWMARK */
515		nla_total_size(4) +
516		0;
517}
518
519static int ipip_fill_info(struct sk_buff *skb, const struct net_device *dev)
520{
521	struct ip_tunnel *tunnel = netdev_priv(dev);
522	struct ip_tunnel_parm_kern *parm = &tunnel->parms;
523
524	if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) ||
525	    nla_put_in_addr(skb, IFLA_IPTUN_LOCAL, parm->iph.saddr) ||
526	    nla_put_in_addr(skb, IFLA_IPTUN_REMOTE, parm->iph.daddr) ||
527	    nla_put_u8(skb, IFLA_IPTUN_TTL, parm->iph.ttl) ||
528	    nla_put_u8(skb, IFLA_IPTUN_TOS, parm->iph.tos) ||
529	    nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->iph.protocol) ||
530	    nla_put_u8(skb, IFLA_IPTUN_PMTUDISC,
531		       !!(parm->iph.frag_off & htons(IP_DF))) ||
532	    nla_put_u32(skb, IFLA_IPTUN_FWMARK, tunnel->fwmark))
533		goto nla_put_failure;
534
535	if (nla_put_u16(skb, IFLA_IPTUN_ENCAP_TYPE,
536			tunnel->encap.type) ||
537	    nla_put_be16(skb, IFLA_IPTUN_ENCAP_SPORT,
538			 tunnel->encap.sport) ||
539	    nla_put_be16(skb, IFLA_IPTUN_ENCAP_DPORT,
540			 tunnel->encap.dport) ||
541	    nla_put_u16(skb, IFLA_IPTUN_ENCAP_FLAGS,
542			tunnel->encap.flags))
543		goto nla_put_failure;
544
545	if (tunnel->collect_md)
546		if (nla_put_flag(skb, IFLA_IPTUN_COLLECT_METADATA))
547			goto nla_put_failure;
548	return 0;
549
550nla_put_failure:
551	return -EMSGSIZE;
552}
553
554static const struct nla_policy ipip_policy[IFLA_IPTUN_MAX + 1] = {
555	[IFLA_IPTUN_LINK]		= { .type = NLA_U32 },
556	[IFLA_IPTUN_LOCAL]		= { .type = NLA_U32 },
557	[IFLA_IPTUN_REMOTE]		= { .type = NLA_U32 },
558	[IFLA_IPTUN_TTL]		= { .type = NLA_U8 },
559	[IFLA_IPTUN_TOS]		= { .type = NLA_U8 },
560	[IFLA_IPTUN_PROTO]		= { .type = NLA_U8 },
561	[IFLA_IPTUN_PMTUDISC]		= { .type = NLA_U8 },
562	[IFLA_IPTUN_ENCAP_TYPE]		= { .type = NLA_U16 },
563	[IFLA_IPTUN_ENCAP_FLAGS]	= { .type = NLA_U16 },
564	[IFLA_IPTUN_ENCAP_SPORT]	= { .type = NLA_U16 },
565	[IFLA_IPTUN_ENCAP_DPORT]	= { .type = NLA_U16 },
566	[IFLA_IPTUN_COLLECT_METADATA]	= { .type = NLA_FLAG },
567	[IFLA_IPTUN_FWMARK]		= { .type = NLA_U32 },
568};
569
570static struct rtnl_link_ops ipip_link_ops __read_mostly = {
571	.kind		= "ipip",
572	.maxtype	= IFLA_IPTUN_MAX,
573	.policy		= ipip_policy,
574	.priv_size	= sizeof(struct ip_tunnel),
575	.setup		= ipip_tunnel_setup,
576	.validate	= ipip_tunnel_validate,
577	.newlink	= ipip_newlink,
578	.changelink	= ipip_changelink,
579	.dellink	= ip_tunnel_dellink,
580	.get_size	= ipip_get_size,
581	.fill_info	= ipip_fill_info,
582	.get_link_net	= ip_tunnel_get_link_net,
583};
584
585static struct xfrm_tunnel ipip_handler __read_mostly = {
586	.handler	=	ipip_rcv,
587	.err_handler	=	ipip_err,
588	.priority	=	1,
589};
590
591#if IS_ENABLED(CONFIG_MPLS)
592static struct xfrm_tunnel mplsip_handler __read_mostly = {
593	.handler	=	mplsip_rcv,
594	.err_handler	=	ipip_err,
595	.priority	=	1,
596};
597#endif
598
599static int __net_init ipip_init_net(struct net *net)
600{
601	return ip_tunnel_init_net(net, ipip_net_id, &ipip_link_ops, "tunl0");
602}
603
604static void __net_exit ipip_exit_batch_rtnl(struct list_head *list_net,
605					    struct list_head *dev_to_kill)
606{
607	ip_tunnel_delete_nets(list_net, ipip_net_id, &ipip_link_ops,
608			      dev_to_kill);
609}
610
611static struct pernet_operations ipip_net_ops = {
612	.init = ipip_init_net,
613	.exit_batch_rtnl = ipip_exit_batch_rtnl,
614	.id   = &ipip_net_id,
615	.size = sizeof(struct ip_tunnel_net),
616};
617
618static int __init ipip_init(void)
619{
620	int err;
621
622	pr_info("ipip: IPv4 and MPLS over IPv4 tunneling driver\n");
623
624	err = register_pernet_device(&ipip_net_ops);
625	if (err < 0)
626		return err;
627	err = xfrm4_tunnel_register(&ipip_handler, AF_INET);
628	if (err < 0) {
629		pr_info("%s: can't register tunnel\n", __func__);
630		goto xfrm_tunnel_ipip_failed;
631	}
632#if IS_ENABLED(CONFIG_MPLS)
633	err = xfrm4_tunnel_register(&mplsip_handler, AF_MPLS);
634	if (err < 0) {
635		pr_info("%s: can't register tunnel\n", __func__);
636		goto xfrm_tunnel_mplsip_failed;
637	}
638#endif
639	err = rtnl_link_register(&ipip_link_ops);
640	if (err < 0)
641		goto rtnl_link_failed;
642
643out:
644	return err;
645
646rtnl_link_failed:
647#if IS_ENABLED(CONFIG_MPLS)
648	xfrm4_tunnel_deregister(&mplsip_handler, AF_MPLS);
649xfrm_tunnel_mplsip_failed:
650
651#endif
652	xfrm4_tunnel_deregister(&ipip_handler, AF_INET);
653xfrm_tunnel_ipip_failed:
654	unregister_pernet_device(&ipip_net_ops);
655	goto out;
656}
657
658static void __exit ipip_fini(void)
659{
660	rtnl_link_unregister(&ipip_link_ops);
661	if (xfrm4_tunnel_deregister(&ipip_handler, AF_INET))
662		pr_info("%s: can't deregister tunnel\n", __func__);
663#if IS_ENABLED(CONFIG_MPLS)
664	if (xfrm4_tunnel_deregister(&mplsip_handler, AF_MPLS))
665		pr_info("%s: can't deregister tunnel\n", __func__);
666#endif
667	unregister_pernet_device(&ipip_net_ops);
668}
669
670module_init(ipip_init);
671module_exit(ipip_fini);
672MODULE_DESCRIPTION("IP/IP protocol decoder library");
673MODULE_LICENSE("GPL");
674MODULE_ALIAS_RTNL_LINK("ipip");
675MODULE_ALIAS_NETDEV("tunl0");