net: avoid false positives in untrusted gso validation
[muen/linux.git] / net / ipv6 / ip6_gre.c
1 /*
2  *      GRE over IPv6 protocol decoder.
3  *
4  *      Authors: Dmitry Kozlov (xeb@mail.ru)
5  *
6  *      This program is free software; you can redistribute it and/or
7  *      modify it under the terms of the GNU General Public License
8  *      as published by the Free Software Foundation; either version
9  *      2 of the License, or (at your option) any later version.
10  *
11  */
12
13 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14
15 #include <linux/capability.h>
16 #include <linux/module.h>
17 #include <linux/types.h>
18 #include <linux/kernel.h>
19 #include <linux/slab.h>
20 #include <linux/uaccess.h>
21 #include <linux/skbuff.h>
22 #include <linux/netdevice.h>
23 #include <linux/in.h>
24 #include <linux/tcp.h>
25 #include <linux/udp.h>
26 #include <linux/if_arp.h>
27 #include <linux/init.h>
28 #include <linux/in6.h>
29 #include <linux/inetdevice.h>
30 #include <linux/igmp.h>
31 #include <linux/netfilter_ipv4.h>
32 #include <linux/etherdevice.h>
33 #include <linux/if_ether.h>
34 #include <linux/hash.h>
35 #include <linux/if_tunnel.h>
36 #include <linux/ip6_tunnel.h>
37
38 #include <net/sock.h>
39 #include <net/ip.h>
40 #include <net/ip_tunnels.h>
41 #include <net/icmp.h>
42 #include <net/protocol.h>
43 #include <net/addrconf.h>
44 #include <net/arp.h>
45 #include <net/checksum.h>
46 #include <net/dsfield.h>
47 #include <net/inet_ecn.h>
48 #include <net/xfrm.h>
49 #include <net/net_namespace.h>
50 #include <net/netns/generic.h>
51 #include <net/rtnetlink.h>
52
53 #include <net/ipv6.h>
54 #include <net/ip6_fib.h>
55 #include <net/ip6_route.h>
56 #include <net/ip6_tunnel.h>
57 #include <net/gre.h>
58 #include <net/erspan.h>
59 #include <net/dst_metadata.h>
60
61
62 static bool log_ecn_error = true;
63 module_param(log_ecn_error, bool, 0644);
64 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
65
66 #define IP6_GRE_HASH_SIZE_SHIFT  5
67 #define IP6_GRE_HASH_SIZE (1 << IP6_GRE_HASH_SIZE_SHIFT)
68
69 static unsigned int ip6gre_net_id __read_mostly;
70 struct ip6gre_net {
71         struct ip6_tnl __rcu *tunnels[4][IP6_GRE_HASH_SIZE];
72
73         struct ip6_tnl __rcu *collect_md_tun;
74         struct ip6_tnl __rcu *collect_md_tun_erspan;
75         struct net_device *fb_tunnel_dev;
76 };
77
78 static struct rtnl_link_ops ip6gre_link_ops __read_mostly;
79 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly;
80 static struct rtnl_link_ops ip6erspan_tap_ops __read_mostly;
81 static int ip6gre_tunnel_init(struct net_device *dev);
82 static void ip6gre_tunnel_setup(struct net_device *dev);
83 static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t);
84 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu);
85 static void ip6erspan_tnl_link_config(struct ip6_tnl *t, int set_mtu);
86
87 /* Tunnel hash table */
88
89 /*
90    4 hash tables:
91
92    3: (remote,local)
93    2: (remote,*)
94    1: (*,local)
95    0: (*,*)
96
97    We require exact key match i.e. if a key is present in packet
98    it will match only tunnel with the same key; if it is not present,
99    it will match only keyless tunnel.
100
101    All keysless packets, if not matched configured keyless tunnels
102    will match fallback tunnel.
103  */
104
105 #define HASH_KEY(key) (((__force u32)key^((__force u32)key>>4))&(IP6_GRE_HASH_SIZE - 1))
106 static u32 HASH_ADDR(const struct in6_addr *addr)
107 {
108         u32 hash = ipv6_addr_hash(addr);
109
110         return hash_32(hash, IP6_GRE_HASH_SIZE_SHIFT);
111 }
112
113 #define tunnels_r_l     tunnels[3]
114 #define tunnels_r       tunnels[2]
115 #define tunnels_l       tunnels[1]
116 #define tunnels_wc      tunnels[0]
117
118 /* Given src, dst and key, find appropriate for input tunnel. */
119
120 static struct ip6_tnl *ip6gre_tunnel_lookup(struct net_device *dev,
121                 const struct in6_addr *remote, const struct in6_addr *local,
122                 __be32 key, __be16 gre_proto)
123 {
124         struct net *net = dev_net(dev);
125         int link = dev->ifindex;
126         unsigned int h0 = HASH_ADDR(remote);
127         unsigned int h1 = HASH_KEY(key);
128         struct ip6_tnl *t, *cand = NULL;
129         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
130         int dev_type = (gre_proto == htons(ETH_P_TEB) ||
131                         gre_proto == htons(ETH_P_ERSPAN) ||
132                         gre_proto == htons(ETH_P_ERSPAN2)) ?
133                        ARPHRD_ETHER : ARPHRD_IP6GRE;
134         int score, cand_score = 4;
135
136         for_each_ip_tunnel_rcu(t, ign->tunnels_r_l[h0 ^ h1]) {
137                 if (!ipv6_addr_equal(local, &t->parms.laddr) ||
138                     !ipv6_addr_equal(remote, &t->parms.raddr) ||
139                     key != t->parms.i_key ||
140                     !(t->dev->flags & IFF_UP))
141                         continue;
142
143                 if (t->dev->type != ARPHRD_IP6GRE &&
144                     t->dev->type != dev_type)
145                         continue;
146
147                 score = 0;
148                 if (t->parms.link != link)
149                         score |= 1;
150                 if (t->dev->type != dev_type)
151                         score |= 2;
152                 if (score == 0)
153                         return t;
154
155                 if (score < cand_score) {
156                         cand = t;
157                         cand_score = score;
158                 }
159         }
160
161         for_each_ip_tunnel_rcu(t, ign->tunnels_r[h0 ^ h1]) {
162                 if (!ipv6_addr_equal(remote, &t->parms.raddr) ||
163                     key != t->parms.i_key ||
164                     !(t->dev->flags & IFF_UP))
165                         continue;
166
167                 if (t->dev->type != ARPHRD_IP6GRE &&
168                     t->dev->type != dev_type)
169                         continue;
170
171                 score = 0;
172                 if (t->parms.link != link)
173                         score |= 1;
174                 if (t->dev->type != dev_type)
175                         score |= 2;
176                 if (score == 0)
177                         return t;
178
179                 if (score < cand_score) {
180                         cand = t;
181                         cand_score = score;
182                 }
183         }
184
185         for_each_ip_tunnel_rcu(t, ign->tunnels_l[h1]) {
186                 if ((!ipv6_addr_equal(local, &t->parms.laddr) &&
187                           (!ipv6_addr_equal(local, &t->parms.raddr) ||
188                                  !ipv6_addr_is_multicast(local))) ||
189                     key != t->parms.i_key ||
190                     !(t->dev->flags & IFF_UP))
191                         continue;
192
193                 if (t->dev->type != ARPHRD_IP6GRE &&
194                     t->dev->type != dev_type)
195                         continue;
196
197                 score = 0;
198                 if (t->parms.link != link)
199                         score |= 1;
200                 if (t->dev->type != dev_type)
201                         score |= 2;
202                 if (score == 0)
203                         return t;
204
205                 if (score < cand_score) {
206                         cand = t;
207                         cand_score = score;
208                 }
209         }
210
211         for_each_ip_tunnel_rcu(t, ign->tunnels_wc[h1]) {
212                 if (t->parms.i_key != key ||
213                     !(t->dev->flags & IFF_UP))
214                         continue;
215
216                 if (t->dev->type != ARPHRD_IP6GRE &&
217                     t->dev->type != dev_type)
218                         continue;
219
220                 score = 0;
221                 if (t->parms.link != link)
222                         score |= 1;
223                 if (t->dev->type != dev_type)
224                         score |= 2;
225                 if (score == 0)
226                         return t;
227
228                 if (score < cand_score) {
229                         cand = t;
230                         cand_score = score;
231                 }
232         }
233
234         if (cand)
235                 return cand;
236
237         if (gre_proto == htons(ETH_P_ERSPAN) ||
238             gre_proto == htons(ETH_P_ERSPAN2))
239                 t = rcu_dereference(ign->collect_md_tun_erspan);
240         else
241                 t = rcu_dereference(ign->collect_md_tun);
242
243         if (t && t->dev->flags & IFF_UP)
244                 return t;
245
246         dev = ign->fb_tunnel_dev;
247         if (dev && dev->flags & IFF_UP)
248                 return netdev_priv(dev);
249
250         return NULL;
251 }
252
253 static struct ip6_tnl __rcu **__ip6gre_bucket(struct ip6gre_net *ign,
254                 const struct __ip6_tnl_parm *p)
255 {
256         const struct in6_addr *remote = &p->raddr;
257         const struct in6_addr *local = &p->laddr;
258         unsigned int h = HASH_KEY(p->i_key);
259         int prio = 0;
260
261         if (!ipv6_addr_any(local))
262                 prio |= 1;
263         if (!ipv6_addr_any(remote) && !ipv6_addr_is_multicast(remote)) {
264                 prio |= 2;
265                 h ^= HASH_ADDR(remote);
266         }
267
268         return &ign->tunnels[prio][h];
269 }
270
271 static void ip6gre_tunnel_link_md(struct ip6gre_net *ign, struct ip6_tnl *t)
272 {
273         if (t->parms.collect_md)
274                 rcu_assign_pointer(ign->collect_md_tun, t);
275 }
276
277 static void ip6erspan_tunnel_link_md(struct ip6gre_net *ign, struct ip6_tnl *t)
278 {
279         if (t->parms.collect_md)
280                 rcu_assign_pointer(ign->collect_md_tun_erspan, t);
281 }
282
283 static void ip6gre_tunnel_unlink_md(struct ip6gre_net *ign, struct ip6_tnl *t)
284 {
285         if (t->parms.collect_md)
286                 rcu_assign_pointer(ign->collect_md_tun, NULL);
287 }
288
289 static void ip6erspan_tunnel_unlink_md(struct ip6gre_net *ign,
290                                        struct ip6_tnl *t)
291 {
292         if (t->parms.collect_md)
293                 rcu_assign_pointer(ign->collect_md_tun_erspan, NULL);
294 }
295
296 static inline struct ip6_tnl __rcu **ip6gre_bucket(struct ip6gre_net *ign,
297                 const struct ip6_tnl *t)
298 {
299         return __ip6gre_bucket(ign, &t->parms);
300 }
301
302 static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t)
303 {
304         struct ip6_tnl __rcu **tp = ip6gre_bucket(ign, t);
305
306         rcu_assign_pointer(t->next, rtnl_dereference(*tp));
307         rcu_assign_pointer(*tp, t);
308 }
309
310 static void ip6gre_tunnel_unlink(struct ip6gre_net *ign, struct ip6_tnl *t)
311 {
312         struct ip6_tnl __rcu **tp;
313         struct ip6_tnl *iter;
314
315         for (tp = ip6gre_bucket(ign, t);
316              (iter = rtnl_dereference(*tp)) != NULL;
317              tp = &iter->next) {
318                 if (t == iter) {
319                         rcu_assign_pointer(*tp, t->next);
320                         break;
321                 }
322         }
323 }
324
325 static struct ip6_tnl *ip6gre_tunnel_find(struct net *net,
326                                            const struct __ip6_tnl_parm *parms,
327                                            int type)
328 {
329         const struct in6_addr *remote = &parms->raddr;
330         const struct in6_addr *local = &parms->laddr;
331         __be32 key = parms->i_key;
332         int link = parms->link;
333         struct ip6_tnl *t;
334         struct ip6_tnl __rcu **tp;
335         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
336
337         for (tp = __ip6gre_bucket(ign, parms);
338              (t = rtnl_dereference(*tp)) != NULL;
339              tp = &t->next)
340                 if (ipv6_addr_equal(local, &t->parms.laddr) &&
341                     ipv6_addr_equal(remote, &t->parms.raddr) &&
342                     key == t->parms.i_key &&
343                     link == t->parms.link &&
344                     type == t->dev->type)
345                         break;
346
347         return t;
348 }
349
350 static struct ip6_tnl *ip6gre_tunnel_locate(struct net *net,
351                 const struct __ip6_tnl_parm *parms, int create)
352 {
353         struct ip6_tnl *t, *nt;
354         struct net_device *dev;
355         char name[IFNAMSIZ];
356         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
357
358         t = ip6gre_tunnel_find(net, parms, ARPHRD_IP6GRE);
359         if (t && create)
360                 return NULL;
361         if (t || !create)
362                 return t;
363
364         if (parms->name[0]) {
365                 if (!dev_valid_name(parms->name))
366                         return NULL;
367                 strlcpy(name, parms->name, IFNAMSIZ);
368         } else {
369                 strcpy(name, "ip6gre%d");
370         }
371         dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN,
372                            ip6gre_tunnel_setup);
373         if (!dev)
374                 return NULL;
375
376         dev_net_set(dev, net);
377
378         nt = netdev_priv(dev);
379         nt->parms = *parms;
380         dev->rtnl_link_ops = &ip6gre_link_ops;
381
382         nt->dev = dev;
383         nt->net = dev_net(dev);
384
385         if (register_netdevice(dev) < 0)
386                 goto failed_free;
387
388         ip6gre_tnl_link_config(nt, 1);
389
390         /* Can use a lockless transmit, unless we generate output sequences */
391         if (!(nt->parms.o_flags & TUNNEL_SEQ))
392                 dev->features |= NETIF_F_LLTX;
393
394         dev_hold(dev);
395         ip6gre_tunnel_link(ign, nt);
396         return nt;
397
398 failed_free:
399         free_netdev(dev);
400         return NULL;
401 }
402
403 static void ip6erspan_tunnel_uninit(struct net_device *dev)
404 {
405         struct ip6_tnl *t = netdev_priv(dev);
406         struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
407
408         ip6erspan_tunnel_unlink_md(ign, t);
409         ip6gre_tunnel_unlink(ign, t);
410         dst_cache_reset(&t->dst_cache);
411         dev_put(dev);
412 }
413
414 static void ip6gre_tunnel_uninit(struct net_device *dev)
415 {
416         struct ip6_tnl *t = netdev_priv(dev);
417         struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
418
419         ip6gre_tunnel_unlink_md(ign, t);
420         ip6gre_tunnel_unlink(ign, t);
421         dst_cache_reset(&t->dst_cache);
422         dev_put(dev);
423 }
424
425
426 static int ip6gre_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
427                        u8 type, u8 code, int offset, __be32 info)
428 {
429         struct net *net = dev_net(skb->dev);
430         const struct ipv6hdr *ipv6h;
431         struct tnl_ptk_info tpi;
432         struct ip6_tnl *t;
433
434         if (gre_parse_header(skb, &tpi, NULL, htons(ETH_P_IPV6),
435                              offset) < 0)
436                 return -EINVAL;
437
438         ipv6h = (const struct ipv6hdr *)skb->data;
439         t = ip6gre_tunnel_lookup(skb->dev, &ipv6h->daddr, &ipv6h->saddr,
440                                  tpi.key, tpi.proto);
441         if (!t)
442                 return -ENOENT;
443
444         switch (type) {
445                 struct ipv6_tlv_tnl_enc_lim *tel;
446                 __u32 teli;
447         case ICMPV6_DEST_UNREACH:
448                 net_dbg_ratelimited("%s: Path to destination invalid or inactive!\n",
449                                     t->parms.name);
450                 if (code != ICMPV6_PORT_UNREACH)
451                         break;
452                 return 0;
453         case ICMPV6_TIME_EXCEED:
454                 if (code == ICMPV6_EXC_HOPLIMIT) {
455                         net_dbg_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n",
456                                             t->parms.name);
457                         break;
458                 }
459                 return 0;
460         case ICMPV6_PARAMPROB:
461                 teli = 0;
462                 if (code == ICMPV6_HDR_FIELD)
463                         teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data);
464
465                 if (teli && teli == be32_to_cpu(info) - 2) {
466                         tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli];
467                         if (tel->encap_limit == 0) {
468                                 net_dbg_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n",
469                                                     t->parms.name);
470                         }
471                 } else {
472                         net_dbg_ratelimited("%s: Recipient unable to parse tunneled packet!\n",
473                                             t->parms.name);
474                 }
475                 return 0;
476         case ICMPV6_PKT_TOOBIG:
477                 ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL));
478                 return 0;
479         case NDISC_REDIRECT:
480                 ip6_redirect(skb, net, skb->dev->ifindex, 0,
481                              sock_net_uid(net, NULL));
482                 return 0;
483         }
484
485         if (time_before(jiffies, t->err_time + IP6TUNNEL_ERR_TIMEO))
486                 t->err_count++;
487         else
488                 t->err_count = 1;
489         t->err_time = jiffies;
490
491         return 0;
492 }
493
494 static int ip6gre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi)
495 {
496         const struct ipv6hdr *ipv6h;
497         struct ip6_tnl *tunnel;
498
499         ipv6h = ipv6_hdr(skb);
500         tunnel = ip6gre_tunnel_lookup(skb->dev,
501                                       &ipv6h->saddr, &ipv6h->daddr, tpi->key,
502                                       tpi->proto);
503         if (tunnel) {
504                 if (tunnel->parms.collect_md) {
505                         struct metadata_dst *tun_dst;
506                         __be64 tun_id;
507                         __be16 flags;
508
509                         flags = tpi->flags;
510                         tun_id = key32_to_tunnel_id(tpi->key);
511
512                         tun_dst = ipv6_tun_rx_dst(skb, flags, tun_id, 0);
513                         if (!tun_dst)
514                                 return PACKET_REJECT;
515
516                         ip6_tnl_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
517                 } else {
518                         ip6_tnl_rcv(tunnel, skb, tpi, NULL, log_ecn_error);
519                 }
520
521                 return PACKET_RCVD;
522         }
523
524         return PACKET_REJECT;
525 }
526
527 static int ip6erspan_rcv(struct sk_buff *skb, int gre_hdr_len,
528                          struct tnl_ptk_info *tpi)
529 {
530         struct erspan_base_hdr *ershdr;
531         struct erspan_metadata *pkt_md;
532         const struct ipv6hdr *ipv6h;
533         struct erspan_md2 *md2;
534         struct ip6_tnl *tunnel;
535         u8 ver;
536
537         ipv6h = ipv6_hdr(skb);
538         ershdr = (struct erspan_base_hdr *)skb->data;
539         ver = ershdr->ver;
540
541         tunnel = ip6gre_tunnel_lookup(skb->dev,
542                                       &ipv6h->saddr, &ipv6h->daddr, tpi->key,
543                                       tpi->proto);
544         if (tunnel) {
545                 int len = erspan_hdr_len(ver);
546
547                 if (unlikely(!pskb_may_pull(skb, len)))
548                         return PACKET_REJECT;
549
550                 ershdr = (struct erspan_base_hdr *)skb->data;
551                 pkt_md = (struct erspan_metadata *)(ershdr + 1);
552
553                 if (__iptunnel_pull_header(skb, len,
554                                            htons(ETH_P_TEB),
555                                            false, false) < 0)
556                         return PACKET_REJECT;
557
558                 if (tunnel->parms.collect_md) {
559                         struct metadata_dst *tun_dst;
560                         struct ip_tunnel_info *info;
561                         struct erspan_metadata *md;
562                         __be64 tun_id;
563                         __be16 flags;
564
565                         tpi->flags |= TUNNEL_KEY;
566                         flags = tpi->flags;
567                         tun_id = key32_to_tunnel_id(tpi->key);
568
569                         tun_dst = ipv6_tun_rx_dst(skb, flags, tun_id,
570                                                   sizeof(*md));
571                         if (!tun_dst)
572                                 return PACKET_REJECT;
573
574                         info = &tun_dst->u.tun_info;
575                         md = ip_tunnel_info_opts(info);
576                         md->version = ver;
577                         md2 = &md->u.md2;
578                         memcpy(md2, pkt_md, ver == 1 ? ERSPAN_V1_MDSIZE :
579                                                        ERSPAN_V2_MDSIZE);
580                         info->key.tun_flags |= TUNNEL_ERSPAN_OPT;
581                         info->options_len = sizeof(*md);
582
583                         ip6_tnl_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
584
585                 } else {
586                         ip6_tnl_rcv(tunnel, skb, tpi, NULL, log_ecn_error);
587                 }
588
589                 return PACKET_RCVD;
590         }
591
592         return PACKET_REJECT;
593 }
594
595 static int gre_rcv(struct sk_buff *skb)
596 {
597         struct tnl_ptk_info tpi;
598         bool csum_err = false;
599         int hdr_len;
600
601         hdr_len = gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IPV6), 0);
602         if (hdr_len < 0)
603                 goto drop;
604
605         if (iptunnel_pull_header(skb, hdr_len, tpi.proto, false))
606                 goto drop;
607
608         if (unlikely(tpi.proto == htons(ETH_P_ERSPAN) ||
609                      tpi.proto == htons(ETH_P_ERSPAN2))) {
610                 if (ip6erspan_rcv(skb, hdr_len, &tpi) == PACKET_RCVD)
611                         return 0;
612                 goto out;
613         }
614
615         if (ip6gre_rcv(skb, &tpi) == PACKET_RCVD)
616                 return 0;
617
618 out:
619         icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
620 drop:
621         kfree_skb(skb);
622         return 0;
623 }
624
625 static int gre_handle_offloads(struct sk_buff *skb, bool csum)
626 {
627         return iptunnel_handle_offloads(skb,
628                                         csum ? SKB_GSO_GRE_CSUM : SKB_GSO_GRE);
629 }
630
631 static void prepare_ip6gre_xmit_ipv4(struct sk_buff *skb,
632                                      struct net_device *dev,
633                                      struct flowi6 *fl6, __u8 *dsfield,
634                                      int *encap_limit)
635 {
636         const struct iphdr *iph = ip_hdr(skb);
637         struct ip6_tnl *t = netdev_priv(dev);
638
639         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
640                 *encap_limit = t->parms.encap_limit;
641
642         memcpy(fl6, &t->fl.u.ip6, sizeof(*fl6));
643
644         if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
645                 *dsfield = ipv4_get_dsfield(iph);
646         else
647                 *dsfield = ip6_tclass(t->parms.flowinfo);
648
649         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
650                 fl6->flowi6_mark = skb->mark;
651         else
652                 fl6->flowi6_mark = t->parms.fwmark;
653
654         fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
655 }
656
657 static int prepare_ip6gre_xmit_ipv6(struct sk_buff *skb,
658                                     struct net_device *dev,
659                                     struct flowi6 *fl6, __u8 *dsfield,
660                                     int *encap_limit)
661 {
662         struct ipv6hdr *ipv6h = ipv6_hdr(skb);
663         struct ip6_tnl *t = netdev_priv(dev);
664         __u16 offset;
665
666         offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb));
667         /* ip6_tnl_parse_tlv_enc_lim() might have reallocated skb->head */
668
669         if (offset > 0) {
670                 struct ipv6_tlv_tnl_enc_lim *tel;
671
672                 tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset];
673                 if (tel->encap_limit == 0) {
674                         icmpv6_send(skb, ICMPV6_PARAMPROB,
675                                     ICMPV6_HDR_FIELD, offset + 2);
676                         return -1;
677                 }
678                 *encap_limit = tel->encap_limit - 1;
679         } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) {
680                 *encap_limit = t->parms.encap_limit;
681         }
682
683         memcpy(fl6, &t->fl.u.ip6, sizeof(*fl6));
684
685         if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
686                 *dsfield = ipv6_get_dsfield(ipv6h);
687         else
688                 *dsfield = ip6_tclass(t->parms.flowinfo);
689
690         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)
691                 fl6->flowlabel |= ip6_flowlabel(ipv6h);
692
693         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
694                 fl6->flowi6_mark = skb->mark;
695         else
696                 fl6->flowi6_mark = t->parms.fwmark;
697
698         fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
699
700         return 0;
701 }
702
703 static netdev_tx_t __gre6_xmit(struct sk_buff *skb,
704                                struct net_device *dev, __u8 dsfield,
705                                struct flowi6 *fl6, int encap_limit,
706                                __u32 *pmtu, __be16 proto)
707 {
708         struct ip6_tnl *tunnel = netdev_priv(dev);
709         __be16 protocol;
710
711         if (dev->type == ARPHRD_ETHER)
712                 IPCB(skb)->flags = 0;
713
714         if (dev->header_ops && dev->type == ARPHRD_IP6GRE)
715                 fl6->daddr = ((struct ipv6hdr *)skb->data)->daddr;
716         else
717                 fl6->daddr = tunnel->parms.raddr;
718
719         if (skb_cow_head(skb, dev->needed_headroom ?: tunnel->hlen))
720                 return -ENOMEM;
721
722         /* Push GRE header. */
723         protocol = (dev->type == ARPHRD_ETHER) ? htons(ETH_P_TEB) : proto;
724
725         if (tunnel->parms.collect_md) {
726                 struct ip_tunnel_info *tun_info;
727                 const struct ip_tunnel_key *key;
728                 __be16 flags;
729
730                 tun_info = skb_tunnel_info(skb);
731                 if (unlikely(!tun_info ||
732                              !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
733                              ip_tunnel_info_af(tun_info) != AF_INET6))
734                         return -EINVAL;
735
736                 key = &tun_info->key;
737                 memset(fl6, 0, sizeof(*fl6));
738                 fl6->flowi6_proto = IPPROTO_GRE;
739                 fl6->daddr = key->u.ipv6.dst;
740                 fl6->flowlabel = key->label;
741                 fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
742
743                 dsfield = key->tos;
744                 flags = key->tun_flags &
745                         (TUNNEL_CSUM | TUNNEL_KEY | TUNNEL_SEQ);
746                 tunnel->tun_hlen = gre_calc_hlen(flags);
747
748                 gre_build_header(skb, tunnel->tun_hlen,
749                                  flags, protocol,
750                                  tunnel_id_to_key32(tun_info->key.tun_id),
751                                  (flags & TUNNEL_SEQ) ? htonl(tunnel->o_seqno++)
752                                                       : 0);
753
754         } else {
755                 if (tunnel->parms.o_flags & TUNNEL_SEQ)
756                         tunnel->o_seqno++;
757
758                 gre_build_header(skb, tunnel->tun_hlen, tunnel->parms.o_flags,
759                                  protocol, tunnel->parms.o_key,
760                                  htonl(tunnel->o_seqno));
761         }
762
763         return ip6_tnl_xmit(skb, dev, dsfield, fl6, encap_limit, pmtu,
764                             NEXTHDR_GRE);
765 }
766
767 static inline int ip6gre_xmit_ipv4(struct sk_buff *skb, struct net_device *dev)
768 {
769         struct ip6_tnl *t = netdev_priv(dev);
770         int encap_limit = -1;
771         struct flowi6 fl6;
772         __u8 dsfield = 0;
773         __u32 mtu;
774         int err;
775
776         memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
777
778         if (!t->parms.collect_md)
779                 prepare_ip6gre_xmit_ipv4(skb, dev, &fl6,
780                                          &dsfield, &encap_limit);
781
782         err = gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM));
783         if (err)
784                 return -1;
785
786         err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
787                           skb->protocol);
788         if (err != 0) {
789                 /* XXX: send ICMP error even if DF is not set. */
790                 if (err == -EMSGSIZE)
791                         icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
792                                   htonl(mtu));
793                 return -1;
794         }
795
796         return 0;
797 }
798
799 static inline int ip6gre_xmit_ipv6(struct sk_buff *skb, struct net_device *dev)
800 {
801         struct ip6_tnl *t = netdev_priv(dev);
802         struct ipv6hdr *ipv6h = ipv6_hdr(skb);
803         int encap_limit = -1;
804         struct flowi6 fl6;
805         __u8 dsfield = 0;
806         __u32 mtu;
807         int err;
808
809         if (ipv6_addr_equal(&t->parms.raddr, &ipv6h->saddr))
810                 return -1;
811
812         if (!t->parms.collect_md &&
813             prepare_ip6gre_xmit_ipv6(skb, dev, &fl6, &dsfield, &encap_limit))
814                 return -1;
815
816         if (gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM)))
817                 return -1;
818
819         err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit,
820                           &mtu, skb->protocol);
821         if (err != 0) {
822                 if (err == -EMSGSIZE)
823                         icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
824                 return -1;
825         }
826
827         return 0;
828 }
829
830 /**
831  * ip6gre_tnl_addr_conflict - compare packet addresses to tunnel's own
832  *   @t: the outgoing tunnel device
833  *   @hdr: IPv6 header from the incoming packet
834  *
835  * Description:
836  *   Avoid trivial tunneling loop by checking that tunnel exit-point
837  *   doesn't match source of incoming packet.
838  *
839  * Return:
840  *   1 if conflict,
841  *   0 else
842  **/
843
844 static inline bool ip6gre_tnl_addr_conflict(const struct ip6_tnl *t,
845         const struct ipv6hdr *hdr)
846 {
847         return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
848 }
849
850 static int ip6gre_xmit_other(struct sk_buff *skb, struct net_device *dev)
851 {
852         struct ip6_tnl *t = netdev_priv(dev);
853         int encap_limit = -1;
854         struct flowi6 fl6;
855         __u32 mtu;
856         int err;
857
858         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
859                 encap_limit = t->parms.encap_limit;
860
861         if (!t->parms.collect_md)
862                 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
863
864         err = gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM));
865         if (err)
866                 return err;
867
868         err = __gre6_xmit(skb, dev, 0, &fl6, encap_limit, &mtu, skb->protocol);
869
870         return err;
871 }
872
873 static netdev_tx_t ip6gre_tunnel_xmit(struct sk_buff *skb,
874         struct net_device *dev)
875 {
876         struct ip6_tnl *t = netdev_priv(dev);
877         struct net_device_stats *stats = &t->dev->stats;
878         int ret;
879
880         if (!pskb_inet_may_pull(skb))
881                 goto tx_err;
882
883         if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr))
884                 goto tx_err;
885
886         switch (skb->protocol) {
887         case htons(ETH_P_IP):
888                 ret = ip6gre_xmit_ipv4(skb, dev);
889                 break;
890         case htons(ETH_P_IPV6):
891                 ret = ip6gre_xmit_ipv6(skb, dev);
892                 break;
893         default:
894                 ret = ip6gre_xmit_other(skb, dev);
895                 break;
896         }
897
898         if (ret < 0)
899                 goto tx_err;
900
901         return NETDEV_TX_OK;
902
903 tx_err:
904         stats->tx_errors++;
905         stats->tx_dropped++;
906         kfree_skb(skb);
907         return NETDEV_TX_OK;
908 }
909
910 static netdev_tx_t ip6erspan_tunnel_xmit(struct sk_buff *skb,
911                                          struct net_device *dev)
912 {
913         struct ip6_tnl *t = netdev_priv(dev);
914         struct dst_entry *dst = skb_dst(skb);
915         struct net_device_stats *stats;
916         bool truncate = false;
917         int encap_limit = -1;
918         __u8 dsfield = false;
919         struct flowi6 fl6;
920         int err = -EINVAL;
921         __be16 proto;
922         __u32 mtu;
923         int nhoff;
924         int thoff;
925
926         if (!pskb_inet_may_pull(skb))
927                 goto tx_err;
928
929         if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr))
930                 goto tx_err;
931
932         if (gre_handle_offloads(skb, false))
933                 goto tx_err;
934
935         if (skb->len > dev->mtu + dev->hard_header_len) {
936                 pskb_trim(skb, dev->mtu + dev->hard_header_len);
937                 truncate = true;
938         }
939
940         nhoff = skb_network_header(skb) - skb_mac_header(skb);
941         if (skb->protocol == htons(ETH_P_IP) &&
942             (ntohs(ip_hdr(skb)->tot_len) > skb->len - nhoff))
943                 truncate = true;
944
945         thoff = skb_transport_header(skb) - skb_mac_header(skb);
946         if (skb->protocol == htons(ETH_P_IPV6) &&
947             (ntohs(ipv6_hdr(skb)->payload_len) > skb->len - thoff))
948                 truncate = true;
949
950         if (skb_cow_head(skb, dev->needed_headroom ?: t->hlen))
951                 goto tx_err;
952
953         t->parms.o_flags &= ~TUNNEL_KEY;
954         IPCB(skb)->flags = 0;
955
956         /* For collect_md mode, derive fl6 from the tunnel key,
957          * for native mode, call prepare_ip6gre_xmit_{ipv4,ipv6}.
958          */
959         if (t->parms.collect_md) {
960                 struct ip_tunnel_info *tun_info;
961                 const struct ip_tunnel_key *key;
962                 struct erspan_metadata *md;
963                 __be32 tun_id;
964
965                 tun_info = skb_tunnel_info(skb);
966                 if (unlikely(!tun_info ||
967                              !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
968                              ip_tunnel_info_af(tun_info) != AF_INET6))
969                         return -EINVAL;
970
971                 key = &tun_info->key;
972                 memset(&fl6, 0, sizeof(fl6));
973                 fl6.flowi6_proto = IPPROTO_GRE;
974                 fl6.daddr = key->u.ipv6.dst;
975                 fl6.flowlabel = key->label;
976                 fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL);
977
978                 dsfield = key->tos;
979                 if (!(tun_info->key.tun_flags & TUNNEL_ERSPAN_OPT))
980                         goto tx_err;
981                 md = ip_tunnel_info_opts(tun_info);
982                 if (!md)
983                         goto tx_err;
984
985                 tun_id = tunnel_id_to_key32(key->tun_id);
986                 if (md->version == 1) {
987                         erspan_build_header(skb,
988                                             ntohl(tun_id),
989                                             ntohl(md->u.index), truncate,
990                                             false);
991                 } else if (md->version == 2) {
992                         erspan_build_header_v2(skb,
993                                                ntohl(tun_id),
994                                                md->u.md2.dir,
995                                                get_hwid(&md->u.md2),
996                                                truncate, false);
997                 } else {
998                         goto tx_err;
999                 }
1000         } else {
1001                 switch (skb->protocol) {
1002                 case htons(ETH_P_IP):
1003                         memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
1004                         prepare_ip6gre_xmit_ipv4(skb, dev, &fl6,
1005                                                  &dsfield, &encap_limit);
1006                         break;
1007                 case htons(ETH_P_IPV6):
1008                         if (ipv6_addr_equal(&t->parms.raddr, &ipv6_hdr(skb)->saddr))
1009                                 goto tx_err;
1010                         if (prepare_ip6gre_xmit_ipv6(skb, dev, &fl6,
1011                                                      &dsfield, &encap_limit))
1012                                 goto tx_err;
1013                         break;
1014                 default:
1015                         memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
1016                         break;
1017                 }
1018
1019                 if (t->parms.erspan_ver == 1)
1020                         erspan_build_header(skb, ntohl(t->parms.o_key),
1021                                             t->parms.index,
1022                                             truncate, false);
1023                 else if (t->parms.erspan_ver == 2)
1024                         erspan_build_header_v2(skb, ntohl(t->parms.o_key),
1025                                                t->parms.dir,
1026                                                t->parms.hwid,
1027                                                truncate, false);
1028                 else
1029                         goto tx_err;
1030
1031                 fl6.daddr = t->parms.raddr;
1032         }
1033
1034         /* Push GRE header. */
1035         proto = (t->parms.erspan_ver == 1) ? htons(ETH_P_ERSPAN)
1036                                            : htons(ETH_P_ERSPAN2);
1037         gre_build_header(skb, 8, TUNNEL_SEQ, proto, 0, htonl(t->o_seqno++));
1038
1039         /* TooBig packet may have updated dst->dev's mtu */
1040         if (!t->parms.collect_md && dst && dst_mtu(dst) > dst->dev->mtu)
1041                 dst->ops->update_pmtu(dst, NULL, skb, dst->dev->mtu);
1042
1043         err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
1044                            NEXTHDR_GRE);
1045         if (err != 0) {
1046                 /* XXX: send ICMP error even if DF is not set. */
1047                 if (err == -EMSGSIZE) {
1048                         if (skb->protocol == htons(ETH_P_IP))
1049                                 icmp_send(skb, ICMP_DEST_UNREACH,
1050                                           ICMP_FRAG_NEEDED, htonl(mtu));
1051                         else
1052                                 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
1053                 }
1054
1055                 goto tx_err;
1056         }
1057         return NETDEV_TX_OK;
1058
1059 tx_err:
1060         stats = &t->dev->stats;
1061         stats->tx_errors++;
1062         stats->tx_dropped++;
1063         kfree_skb(skb);
1064         return NETDEV_TX_OK;
1065 }
1066
1067 static void ip6gre_tnl_link_config_common(struct ip6_tnl *t)
1068 {
1069         struct net_device *dev = t->dev;
1070         struct __ip6_tnl_parm *p = &t->parms;
1071         struct flowi6 *fl6 = &t->fl.u.ip6;
1072
1073         if (dev->type != ARPHRD_ETHER) {
1074                 memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr));
1075                 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
1076         }
1077
1078         /* Set up flowi template */
1079         fl6->saddr = p->laddr;
1080         fl6->daddr = p->raddr;
1081         fl6->flowi6_oif = p->link;
1082         fl6->flowlabel = 0;
1083         fl6->flowi6_proto = IPPROTO_GRE;
1084
1085         if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS))
1086                 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo;
1087         if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL))
1088                 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo;
1089
1090         p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET);
1091         p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
1092
1093         if (p->flags&IP6_TNL_F_CAP_XMIT &&
1094                         p->flags&IP6_TNL_F_CAP_RCV && dev->type != ARPHRD_ETHER)
1095                 dev->flags |= IFF_POINTOPOINT;
1096         else
1097                 dev->flags &= ~IFF_POINTOPOINT;
1098 }
1099
1100 static void ip6gre_tnl_link_config_route(struct ip6_tnl *t, int set_mtu,
1101                                          int t_hlen)
1102 {
1103         const struct __ip6_tnl_parm *p = &t->parms;
1104         struct net_device *dev = t->dev;
1105
1106         if (p->flags & IP6_TNL_F_CAP_XMIT) {
1107                 int strict = (ipv6_addr_type(&p->raddr) &
1108                               (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL));
1109
1110                 struct rt6_info *rt = rt6_lookup(t->net,
1111                                                  &p->raddr, &p->laddr,
1112                                                  p->link, NULL, strict);
1113
1114                 if (!rt)
1115                         return;
1116
1117                 if (rt->dst.dev) {
1118                         dev->needed_headroom = rt->dst.dev->hard_header_len +
1119                                                t_hlen;
1120
1121                         if (set_mtu) {
1122                                 dev->mtu = rt->dst.dev->mtu - t_hlen;
1123                                 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1124                                         dev->mtu -= 8;
1125                                 if (dev->type == ARPHRD_ETHER)
1126                                         dev->mtu -= ETH_HLEN;
1127
1128                                 if (dev->mtu < IPV6_MIN_MTU)
1129                                         dev->mtu = IPV6_MIN_MTU;
1130                         }
1131                 }
1132                 ip6_rt_put(rt);
1133         }
1134 }
1135
1136 static int ip6gre_calc_hlen(struct ip6_tnl *tunnel)
1137 {
1138         int t_hlen;
1139
1140         tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags);
1141         tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen;
1142
1143         t_hlen = tunnel->hlen + sizeof(struct ipv6hdr);
1144         tunnel->dev->needed_headroom = LL_MAX_HEADER + t_hlen;
1145         return t_hlen;
1146 }
1147
1148 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu)
1149 {
1150         ip6gre_tnl_link_config_common(t);
1151         ip6gre_tnl_link_config_route(t, set_mtu, ip6gre_calc_hlen(t));
1152 }
1153
1154 static void ip6gre_tnl_copy_tnl_parm(struct ip6_tnl *t,
1155                                      const struct __ip6_tnl_parm *p)
1156 {
1157         t->parms.laddr = p->laddr;
1158         t->parms.raddr = p->raddr;
1159         t->parms.flags = p->flags;
1160         t->parms.hop_limit = p->hop_limit;
1161         t->parms.encap_limit = p->encap_limit;
1162         t->parms.flowinfo = p->flowinfo;
1163         t->parms.link = p->link;
1164         t->parms.proto = p->proto;
1165         t->parms.i_key = p->i_key;
1166         t->parms.o_key = p->o_key;
1167         t->parms.i_flags = p->i_flags;
1168         t->parms.o_flags = p->o_flags;
1169         t->parms.fwmark = p->fwmark;
1170         t->parms.erspan_ver = p->erspan_ver;
1171         t->parms.index = p->index;
1172         t->parms.dir = p->dir;
1173         t->parms.hwid = p->hwid;
1174         dst_cache_reset(&t->dst_cache);
1175 }
1176
1177 static int ip6gre_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p,
1178                              int set_mtu)
1179 {
1180         ip6gre_tnl_copy_tnl_parm(t, p);
1181         ip6gre_tnl_link_config(t, set_mtu);
1182         return 0;
1183 }
1184
1185 static void ip6gre_tnl_parm_from_user(struct __ip6_tnl_parm *p,
1186         const struct ip6_tnl_parm2 *u)
1187 {
1188         p->laddr = u->laddr;
1189         p->raddr = u->raddr;
1190         p->flags = u->flags;
1191         p->hop_limit = u->hop_limit;
1192         p->encap_limit = u->encap_limit;
1193         p->flowinfo = u->flowinfo;
1194         p->link = u->link;
1195         p->i_key = u->i_key;
1196         p->o_key = u->o_key;
1197         p->i_flags = gre_flags_to_tnl_flags(u->i_flags);
1198         p->o_flags = gre_flags_to_tnl_flags(u->o_flags);
1199         memcpy(p->name, u->name, sizeof(u->name));
1200 }
1201
1202 static void ip6gre_tnl_parm_to_user(struct ip6_tnl_parm2 *u,
1203         const struct __ip6_tnl_parm *p)
1204 {
1205         u->proto = IPPROTO_GRE;
1206         u->laddr = p->laddr;
1207         u->raddr = p->raddr;
1208         u->flags = p->flags;
1209         u->hop_limit = p->hop_limit;
1210         u->encap_limit = p->encap_limit;
1211         u->flowinfo = p->flowinfo;
1212         u->link = p->link;
1213         u->i_key = p->i_key;
1214         u->o_key = p->o_key;
1215         u->i_flags = gre_tnl_flags_to_gre_flags(p->i_flags);
1216         u->o_flags = gre_tnl_flags_to_gre_flags(p->o_flags);
1217         memcpy(u->name, p->name, sizeof(u->name));
1218 }
1219
1220 static int ip6gre_tunnel_ioctl(struct net_device *dev,
1221         struct ifreq *ifr, int cmd)
1222 {
1223         int err = 0;
1224         struct ip6_tnl_parm2 p;
1225         struct __ip6_tnl_parm p1;
1226         struct ip6_tnl *t = netdev_priv(dev);
1227         struct net *net = t->net;
1228         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1229
1230         memset(&p1, 0, sizeof(p1));
1231
1232         switch (cmd) {
1233         case SIOCGETTUNNEL:
1234                 if (dev == ign->fb_tunnel_dev) {
1235                         if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
1236                                 err = -EFAULT;
1237                                 break;
1238                         }
1239                         ip6gre_tnl_parm_from_user(&p1, &p);
1240                         t = ip6gre_tunnel_locate(net, &p1, 0);
1241                         if (!t)
1242                                 t = netdev_priv(dev);
1243                 }
1244                 memset(&p, 0, sizeof(p));
1245                 ip6gre_tnl_parm_to_user(&p, &t->parms);
1246                 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
1247                         err = -EFAULT;
1248                 break;
1249
1250         case SIOCADDTUNNEL:
1251         case SIOCCHGTUNNEL:
1252                 err = -EPERM;
1253                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1254                         goto done;
1255
1256                 err = -EFAULT;
1257                 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1258                         goto done;
1259
1260                 err = -EINVAL;
1261                 if ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING))
1262                         goto done;
1263
1264                 if (!(p.i_flags&GRE_KEY))
1265                         p.i_key = 0;
1266                 if (!(p.o_flags&GRE_KEY))
1267                         p.o_key = 0;
1268
1269                 ip6gre_tnl_parm_from_user(&p1, &p);
1270                 t = ip6gre_tunnel_locate(net, &p1, cmd == SIOCADDTUNNEL);
1271
1272                 if (dev != ign->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
1273                         if (t) {
1274                                 if (t->dev != dev) {
1275                                         err = -EEXIST;
1276                                         break;
1277                                 }
1278                         } else {
1279                                 t = netdev_priv(dev);
1280
1281                                 ip6gre_tunnel_unlink(ign, t);
1282                                 synchronize_net();
1283                                 ip6gre_tnl_change(t, &p1, 1);
1284                                 ip6gre_tunnel_link(ign, t);
1285                                 netdev_state_change(dev);
1286                         }
1287                 }
1288
1289                 if (t) {
1290                         err = 0;
1291
1292                         memset(&p, 0, sizeof(p));
1293                         ip6gre_tnl_parm_to_user(&p, &t->parms);
1294                         if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
1295                                 err = -EFAULT;
1296                 } else
1297                         err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
1298                 break;
1299
1300         case SIOCDELTUNNEL:
1301                 err = -EPERM;
1302                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1303                         goto done;
1304
1305                 if (dev == ign->fb_tunnel_dev) {
1306                         err = -EFAULT;
1307                         if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1308                                 goto done;
1309                         err = -ENOENT;
1310                         ip6gre_tnl_parm_from_user(&p1, &p);
1311                         t = ip6gre_tunnel_locate(net, &p1, 0);
1312                         if (!t)
1313                                 goto done;
1314                         err = -EPERM;
1315                         if (t == netdev_priv(ign->fb_tunnel_dev))
1316                                 goto done;
1317                         dev = t->dev;
1318                 }
1319                 unregister_netdevice(dev);
1320                 err = 0;
1321                 break;
1322
1323         default:
1324                 err = -EINVAL;
1325         }
1326
1327 done:
1328         return err;
1329 }
1330
1331 static int ip6gre_header(struct sk_buff *skb, struct net_device *dev,
1332                          unsigned short type, const void *daddr,
1333                          const void *saddr, unsigned int len)
1334 {
1335         struct ip6_tnl *t = netdev_priv(dev);
1336         struct ipv6hdr *ipv6h;
1337         __be16 *p;
1338
1339         ipv6h = skb_push(skb, t->hlen + sizeof(*ipv6h));
1340         ip6_flow_hdr(ipv6h, 0, ip6_make_flowlabel(dev_net(dev), skb,
1341                                                   t->fl.u.ip6.flowlabel,
1342                                                   true, &t->fl.u.ip6));
1343         ipv6h->hop_limit = t->parms.hop_limit;
1344         ipv6h->nexthdr = NEXTHDR_GRE;
1345         ipv6h->saddr = t->parms.laddr;
1346         ipv6h->daddr = t->parms.raddr;
1347
1348         p = (__be16 *)(ipv6h + 1);
1349         p[0] = t->parms.o_flags;
1350         p[1] = htons(type);
1351
1352         /*
1353          *      Set the source hardware address.
1354          */
1355
1356         if (saddr)
1357                 memcpy(&ipv6h->saddr, saddr, sizeof(struct in6_addr));
1358         if (daddr)
1359                 memcpy(&ipv6h->daddr, daddr, sizeof(struct in6_addr));
1360         if (!ipv6_addr_any(&ipv6h->daddr))
1361                 return t->hlen;
1362
1363         return -t->hlen;
1364 }
1365
1366 static const struct header_ops ip6gre_header_ops = {
1367         .create = ip6gre_header,
1368 };
1369
1370 static const struct net_device_ops ip6gre_netdev_ops = {
1371         .ndo_init               = ip6gre_tunnel_init,
1372         .ndo_uninit             = ip6gre_tunnel_uninit,
1373         .ndo_start_xmit         = ip6gre_tunnel_xmit,
1374         .ndo_do_ioctl           = ip6gre_tunnel_ioctl,
1375         .ndo_change_mtu         = ip6_tnl_change_mtu,
1376         .ndo_get_stats64        = ip_tunnel_get_stats64,
1377         .ndo_get_iflink         = ip6_tnl_get_iflink,
1378 };
1379
1380 static void ip6gre_dev_free(struct net_device *dev)
1381 {
1382         struct ip6_tnl *t = netdev_priv(dev);
1383
1384         gro_cells_destroy(&t->gro_cells);
1385         dst_cache_destroy(&t->dst_cache);
1386         free_percpu(dev->tstats);
1387 }
1388
1389 static void ip6gre_tunnel_setup(struct net_device *dev)
1390 {
1391         dev->netdev_ops = &ip6gre_netdev_ops;
1392         dev->needs_free_netdev = true;
1393         dev->priv_destructor = ip6gre_dev_free;
1394
1395         dev->type = ARPHRD_IP6GRE;
1396
1397         dev->flags |= IFF_NOARP;
1398         dev->addr_len = sizeof(struct in6_addr);
1399         netif_keep_dst(dev);
1400         /* This perm addr will be used as interface identifier by IPv6 */
1401         dev->addr_assign_type = NET_ADDR_RANDOM;
1402         eth_random_addr(dev->perm_addr);
1403 }
1404
1405 #define GRE6_FEATURES (NETIF_F_SG |             \
1406                        NETIF_F_FRAGLIST |       \
1407                        NETIF_F_HIGHDMA |        \
1408                        NETIF_F_HW_CSUM)
1409
1410 static void ip6gre_tnl_init_features(struct net_device *dev)
1411 {
1412         struct ip6_tnl *nt = netdev_priv(dev);
1413
1414         dev->features           |= GRE6_FEATURES;
1415         dev->hw_features        |= GRE6_FEATURES;
1416
1417         if (!(nt->parms.o_flags & TUNNEL_SEQ)) {
1418                 /* TCP offload with GRE SEQ is not supported, nor
1419                  * can we support 2 levels of outer headers requiring
1420                  * an update.
1421                  */
1422                 if (!(nt->parms.o_flags & TUNNEL_CSUM) ||
1423                     nt->encap.type == TUNNEL_ENCAP_NONE) {
1424                         dev->features    |= NETIF_F_GSO_SOFTWARE;
1425                         dev->hw_features |= NETIF_F_GSO_SOFTWARE;
1426                 }
1427
1428                 /* Can use a lockless transmit, unless we generate
1429                  * output sequences
1430                  */
1431                 dev->features |= NETIF_F_LLTX;
1432         }
1433 }
1434
1435 static int ip6gre_tunnel_init_common(struct net_device *dev)
1436 {
1437         struct ip6_tnl *tunnel;
1438         int ret;
1439         int t_hlen;
1440
1441         tunnel = netdev_priv(dev);
1442
1443         tunnel->dev = dev;
1444         tunnel->net = dev_net(dev);
1445         strcpy(tunnel->parms.name, dev->name);
1446
1447         dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1448         if (!dev->tstats)
1449                 return -ENOMEM;
1450
1451         ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1452         if (ret)
1453                 goto cleanup_alloc_pcpu_stats;
1454
1455         ret = gro_cells_init(&tunnel->gro_cells, dev);
1456         if (ret)
1457                 goto cleanup_dst_cache_init;
1458
1459         t_hlen = ip6gre_calc_hlen(tunnel);
1460         dev->mtu = ETH_DATA_LEN - t_hlen;
1461         if (dev->type == ARPHRD_ETHER)
1462                 dev->mtu -= ETH_HLEN;
1463         if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1464                 dev->mtu -= 8;
1465
1466         if (tunnel->parms.collect_md) {
1467                 dev->features |= NETIF_F_NETNS_LOCAL;
1468                 netif_keep_dst(dev);
1469         }
1470         ip6gre_tnl_init_features(dev);
1471
1472         return 0;
1473
1474 cleanup_dst_cache_init:
1475         dst_cache_destroy(&tunnel->dst_cache);
1476 cleanup_alloc_pcpu_stats:
1477         free_percpu(dev->tstats);
1478         dev->tstats = NULL;
1479         return ret;
1480 }
1481
1482 static int ip6gre_tunnel_init(struct net_device *dev)
1483 {
1484         struct ip6_tnl *tunnel;
1485         int ret;
1486
1487         ret = ip6gre_tunnel_init_common(dev);
1488         if (ret)
1489                 return ret;
1490
1491         tunnel = netdev_priv(dev);
1492
1493         if (tunnel->parms.collect_md)
1494                 return 0;
1495
1496         memcpy(dev->dev_addr, &tunnel->parms.laddr, sizeof(struct in6_addr));
1497         memcpy(dev->broadcast, &tunnel->parms.raddr, sizeof(struct in6_addr));
1498
1499         if (ipv6_addr_any(&tunnel->parms.raddr))
1500                 dev->header_ops = &ip6gre_header_ops;
1501
1502         return 0;
1503 }
1504
1505 static void ip6gre_fb_tunnel_init(struct net_device *dev)
1506 {
1507         struct ip6_tnl *tunnel = netdev_priv(dev);
1508
1509         tunnel->dev = dev;
1510         tunnel->net = dev_net(dev);
1511         strcpy(tunnel->parms.name, dev->name);
1512
1513         tunnel->hlen            = sizeof(struct ipv6hdr) + 4;
1514
1515         dev_hold(dev);
1516 }
1517
1518 static struct inet6_protocol ip6gre_protocol __read_mostly = {
1519         .handler     = gre_rcv,
1520         .err_handler = ip6gre_err,
1521         .flags       = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1522 };
1523
1524 static void ip6gre_destroy_tunnels(struct net *net, struct list_head *head)
1525 {
1526         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1527         struct net_device *dev, *aux;
1528         int prio;
1529
1530         for_each_netdev_safe(net, dev, aux)
1531                 if (dev->rtnl_link_ops == &ip6gre_link_ops ||
1532                     dev->rtnl_link_ops == &ip6gre_tap_ops ||
1533                     dev->rtnl_link_ops == &ip6erspan_tap_ops)
1534                         unregister_netdevice_queue(dev, head);
1535
1536         for (prio = 0; prio < 4; prio++) {
1537                 int h;
1538                 for (h = 0; h < IP6_GRE_HASH_SIZE; h++) {
1539                         struct ip6_tnl *t;
1540
1541                         t = rtnl_dereference(ign->tunnels[prio][h]);
1542
1543                         while (t) {
1544                                 /* If dev is in the same netns, it has already
1545                                  * been added to the list by the previous loop.
1546                                  */
1547                                 if (!net_eq(dev_net(t->dev), net))
1548                                         unregister_netdevice_queue(t->dev,
1549                                                                    head);
1550                                 t = rtnl_dereference(t->next);
1551                         }
1552                 }
1553         }
1554 }
1555
1556 static int __net_init ip6gre_init_net(struct net *net)
1557 {
1558         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1559         int err;
1560
1561         if (!net_has_fallback_tunnels(net))
1562                 return 0;
1563         ign->fb_tunnel_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6gre0",
1564                                           NET_NAME_UNKNOWN,
1565                                           ip6gre_tunnel_setup);
1566         if (!ign->fb_tunnel_dev) {
1567                 err = -ENOMEM;
1568                 goto err_alloc_dev;
1569         }
1570         dev_net_set(ign->fb_tunnel_dev, net);
1571         /* FB netdevice is special: we have one, and only one per netns.
1572          * Allowing to move it to another netns is clearly unsafe.
1573          */
1574         ign->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL;
1575
1576
1577         ip6gre_fb_tunnel_init(ign->fb_tunnel_dev);
1578         ign->fb_tunnel_dev->rtnl_link_ops = &ip6gre_link_ops;
1579
1580         err = register_netdev(ign->fb_tunnel_dev);
1581         if (err)
1582                 goto err_reg_dev;
1583
1584         rcu_assign_pointer(ign->tunnels_wc[0],
1585                            netdev_priv(ign->fb_tunnel_dev));
1586         return 0;
1587
1588 err_reg_dev:
1589         free_netdev(ign->fb_tunnel_dev);
1590 err_alloc_dev:
1591         return err;
1592 }
1593
1594 static void __net_exit ip6gre_exit_batch_net(struct list_head *net_list)
1595 {
1596         struct net *net;
1597         LIST_HEAD(list);
1598
1599         rtnl_lock();
1600         list_for_each_entry(net, net_list, exit_list)
1601                 ip6gre_destroy_tunnels(net, &list);
1602         unregister_netdevice_many(&list);
1603         rtnl_unlock();
1604 }
1605
1606 static struct pernet_operations ip6gre_net_ops = {
1607         .init = ip6gre_init_net,
1608         .exit_batch = ip6gre_exit_batch_net,
1609         .id   = &ip6gre_net_id,
1610         .size = sizeof(struct ip6gre_net),
1611 };
1612
1613 static int ip6gre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[],
1614                                   struct netlink_ext_ack *extack)
1615 {
1616         __be16 flags;
1617
1618         if (!data)
1619                 return 0;
1620
1621         flags = 0;
1622         if (data[IFLA_GRE_IFLAGS])
1623                 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1624         if (data[IFLA_GRE_OFLAGS])
1625                 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1626         if (flags & (GRE_VERSION|GRE_ROUTING))
1627                 return -EINVAL;
1628
1629         return 0;
1630 }
1631
1632 static int ip6gre_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1633                                struct netlink_ext_ack *extack)
1634 {
1635         struct in6_addr daddr;
1636
1637         if (tb[IFLA_ADDRESS]) {
1638                 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
1639                         return -EINVAL;
1640                 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
1641                         return -EADDRNOTAVAIL;
1642         }
1643
1644         if (!data)
1645                 goto out;
1646
1647         if (data[IFLA_GRE_REMOTE]) {
1648                 daddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]);
1649                 if (ipv6_addr_any(&daddr))
1650                         return -EINVAL;
1651         }
1652
1653 out:
1654         return ip6gre_tunnel_validate(tb, data, extack);
1655 }
1656
1657 static int ip6erspan_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1658                                   struct netlink_ext_ack *extack)
1659 {
1660         __be16 flags = 0;
1661         int ret, ver = 0;
1662
1663         if (!data)
1664                 return 0;
1665
1666         ret = ip6gre_tap_validate(tb, data, extack);
1667         if (ret)
1668                 return ret;
1669
1670         /* ERSPAN should only have GRE sequence and key flag */
1671         if (data[IFLA_GRE_OFLAGS])
1672                 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1673         if (data[IFLA_GRE_IFLAGS])
1674                 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1675         if (!data[IFLA_GRE_COLLECT_METADATA] &&
1676             flags != (GRE_SEQ | GRE_KEY))
1677                 return -EINVAL;
1678
1679         /* ERSPAN Session ID only has 10-bit. Since we reuse
1680          * 32-bit key field as ID, check it's range.
1681          */
1682         if (data[IFLA_GRE_IKEY] &&
1683             (ntohl(nla_get_be32(data[IFLA_GRE_IKEY])) & ~ID_MASK))
1684                 return -EINVAL;
1685
1686         if (data[IFLA_GRE_OKEY] &&
1687             (ntohl(nla_get_be32(data[IFLA_GRE_OKEY])) & ~ID_MASK))
1688                 return -EINVAL;
1689
1690         if (data[IFLA_GRE_ERSPAN_VER]) {
1691                 ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1692                 if (ver != 1 && ver != 2)
1693                         return -EINVAL;
1694         }
1695
1696         if (ver == 1) {
1697                 if (data[IFLA_GRE_ERSPAN_INDEX]) {
1698                         u32 index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1699
1700                         if (index & ~INDEX_MASK)
1701                                 return -EINVAL;
1702                 }
1703         } else if (ver == 2) {
1704                 if (data[IFLA_GRE_ERSPAN_DIR]) {
1705                         u16 dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1706
1707                         if (dir & ~(DIR_MASK >> DIR_OFFSET))
1708                                 return -EINVAL;
1709                 }
1710
1711                 if (data[IFLA_GRE_ERSPAN_HWID]) {
1712                         u16 hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1713
1714                         if (hwid & ~(HWID_MASK >> HWID_OFFSET))
1715                                 return -EINVAL;
1716                 }
1717         }
1718
1719         return 0;
1720 }
1721
1722 static void ip6erspan_set_version(struct nlattr *data[],
1723                                   struct __ip6_tnl_parm *parms)
1724 {
1725         parms->erspan_ver = 1;
1726         if (data[IFLA_GRE_ERSPAN_VER])
1727                 parms->erspan_ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1728
1729         if (parms->erspan_ver == 1) {
1730                 if (data[IFLA_GRE_ERSPAN_INDEX])
1731                         parms->index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1732         } else if (parms->erspan_ver == 2) {
1733                 if (data[IFLA_GRE_ERSPAN_DIR])
1734                         parms->dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1735                 if (data[IFLA_GRE_ERSPAN_HWID])
1736                         parms->hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1737         }
1738 }
1739
1740 static void ip6gre_netlink_parms(struct nlattr *data[],
1741                                 struct __ip6_tnl_parm *parms)
1742 {
1743         memset(parms, 0, sizeof(*parms));
1744
1745         if (!data)
1746                 return;
1747
1748         if (data[IFLA_GRE_LINK])
1749                 parms->link = nla_get_u32(data[IFLA_GRE_LINK]);
1750
1751         if (data[IFLA_GRE_IFLAGS])
1752                 parms->i_flags = gre_flags_to_tnl_flags(
1753                                 nla_get_be16(data[IFLA_GRE_IFLAGS]));
1754
1755         if (data[IFLA_GRE_OFLAGS])
1756                 parms->o_flags = gre_flags_to_tnl_flags(
1757                                 nla_get_be16(data[IFLA_GRE_OFLAGS]));
1758
1759         if (data[IFLA_GRE_IKEY])
1760                 parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]);
1761
1762         if (data[IFLA_GRE_OKEY])
1763                 parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]);
1764
1765         if (data[IFLA_GRE_LOCAL])
1766                 parms->laddr = nla_get_in6_addr(data[IFLA_GRE_LOCAL]);
1767
1768         if (data[IFLA_GRE_REMOTE])
1769                 parms->raddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]);
1770
1771         if (data[IFLA_GRE_TTL])
1772                 parms->hop_limit = nla_get_u8(data[IFLA_GRE_TTL]);
1773
1774         if (data[IFLA_GRE_ENCAP_LIMIT])
1775                 parms->encap_limit = nla_get_u8(data[IFLA_GRE_ENCAP_LIMIT]);
1776
1777         if (data[IFLA_GRE_FLOWINFO])
1778                 parms->flowinfo = nla_get_be32(data[IFLA_GRE_FLOWINFO]);
1779
1780         if (data[IFLA_GRE_FLAGS])
1781                 parms->flags = nla_get_u32(data[IFLA_GRE_FLAGS]);
1782
1783         if (data[IFLA_GRE_FWMARK])
1784                 parms->fwmark = nla_get_u32(data[IFLA_GRE_FWMARK]);
1785
1786         if (data[IFLA_GRE_COLLECT_METADATA])
1787                 parms->collect_md = true;
1788 }
1789
1790 static int ip6gre_tap_init(struct net_device *dev)
1791 {
1792         int ret;
1793
1794         ret = ip6gre_tunnel_init_common(dev);
1795         if (ret)
1796                 return ret;
1797
1798         dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1799
1800         return 0;
1801 }
1802
1803 static const struct net_device_ops ip6gre_tap_netdev_ops = {
1804         .ndo_init = ip6gre_tap_init,
1805         .ndo_uninit = ip6gre_tunnel_uninit,
1806         .ndo_start_xmit = ip6gre_tunnel_xmit,
1807         .ndo_set_mac_address = eth_mac_addr,
1808         .ndo_validate_addr = eth_validate_addr,
1809         .ndo_change_mtu = ip6_tnl_change_mtu,
1810         .ndo_get_stats64 = ip_tunnel_get_stats64,
1811         .ndo_get_iflink = ip6_tnl_get_iflink,
1812 };
1813
1814 static int ip6erspan_calc_hlen(struct ip6_tnl *tunnel)
1815 {
1816         int t_hlen;
1817
1818         tunnel->tun_hlen = 8;
1819         tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen +
1820                        erspan_hdr_len(tunnel->parms.erspan_ver);
1821
1822         t_hlen = tunnel->hlen + sizeof(struct ipv6hdr);
1823         tunnel->dev->needed_headroom = LL_MAX_HEADER + t_hlen;
1824         return t_hlen;
1825 }
1826
1827 static int ip6erspan_tap_init(struct net_device *dev)
1828 {
1829         struct ip6_tnl *tunnel;
1830         int t_hlen;
1831         int ret;
1832
1833         tunnel = netdev_priv(dev);
1834
1835         tunnel->dev = dev;
1836         tunnel->net = dev_net(dev);
1837         strcpy(tunnel->parms.name, dev->name);
1838
1839         dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1840         if (!dev->tstats)
1841                 return -ENOMEM;
1842
1843         ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1844         if (ret)
1845                 goto cleanup_alloc_pcpu_stats;
1846
1847         ret = gro_cells_init(&tunnel->gro_cells, dev);
1848         if (ret)
1849                 goto cleanup_dst_cache_init;
1850
1851         t_hlen = ip6erspan_calc_hlen(tunnel);
1852         dev->mtu = ETH_DATA_LEN - t_hlen;
1853         if (dev->type == ARPHRD_ETHER)
1854                 dev->mtu -= ETH_HLEN;
1855         if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1856                 dev->mtu -= 8;
1857
1858         dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1859         ip6erspan_tnl_link_config(tunnel, 1);
1860
1861         return 0;
1862
1863 cleanup_dst_cache_init:
1864         dst_cache_destroy(&tunnel->dst_cache);
1865 cleanup_alloc_pcpu_stats:
1866         free_percpu(dev->tstats);
1867         dev->tstats = NULL;
1868         return ret;
1869 }
1870
1871 static const struct net_device_ops ip6erspan_netdev_ops = {
1872         .ndo_init =             ip6erspan_tap_init,
1873         .ndo_uninit =           ip6erspan_tunnel_uninit,
1874         .ndo_start_xmit =       ip6erspan_tunnel_xmit,
1875         .ndo_set_mac_address =  eth_mac_addr,
1876         .ndo_validate_addr =    eth_validate_addr,
1877         .ndo_change_mtu =       ip6_tnl_change_mtu,
1878         .ndo_get_stats64 =      ip_tunnel_get_stats64,
1879         .ndo_get_iflink =       ip6_tnl_get_iflink,
1880 };
1881
1882 static void ip6gre_tap_setup(struct net_device *dev)
1883 {
1884
1885         ether_setup(dev);
1886
1887         dev->max_mtu = 0;
1888         dev->netdev_ops = &ip6gre_tap_netdev_ops;
1889         dev->needs_free_netdev = true;
1890         dev->priv_destructor = ip6gre_dev_free;
1891
1892         dev->features |= NETIF_F_NETNS_LOCAL;
1893         dev->priv_flags &= ~IFF_TX_SKB_SHARING;
1894         dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1895         netif_keep_dst(dev);
1896 }
1897
1898 static bool ip6gre_netlink_encap_parms(struct nlattr *data[],
1899                                        struct ip_tunnel_encap *ipencap)
1900 {
1901         bool ret = false;
1902
1903         memset(ipencap, 0, sizeof(*ipencap));
1904
1905         if (!data)
1906                 return ret;
1907
1908         if (data[IFLA_GRE_ENCAP_TYPE]) {
1909                 ret = true;
1910                 ipencap->type = nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]);
1911         }
1912
1913         if (data[IFLA_GRE_ENCAP_FLAGS]) {
1914                 ret = true;
1915                 ipencap->flags = nla_get_u16(data[IFLA_GRE_ENCAP_FLAGS]);
1916         }
1917
1918         if (data[IFLA_GRE_ENCAP_SPORT]) {
1919                 ret = true;
1920                 ipencap->sport = nla_get_be16(data[IFLA_GRE_ENCAP_SPORT]);
1921         }
1922
1923         if (data[IFLA_GRE_ENCAP_DPORT]) {
1924                 ret = true;
1925                 ipencap->dport = nla_get_be16(data[IFLA_GRE_ENCAP_DPORT]);
1926         }
1927
1928         return ret;
1929 }
1930
1931 static int ip6gre_newlink_common(struct net *src_net, struct net_device *dev,
1932                                  struct nlattr *tb[], struct nlattr *data[],
1933                                  struct netlink_ext_ack *extack)
1934 {
1935         struct ip6_tnl *nt;
1936         struct ip_tunnel_encap ipencap;
1937         int err;
1938
1939         nt = netdev_priv(dev);
1940
1941         if (ip6gre_netlink_encap_parms(data, &ipencap)) {
1942                 int err = ip6_tnl_encap_setup(nt, &ipencap);
1943
1944                 if (err < 0)
1945                         return err;
1946         }
1947
1948         if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS])
1949                 eth_hw_addr_random(dev);
1950
1951         nt->dev = dev;
1952         nt->net = dev_net(dev);
1953
1954         err = register_netdevice(dev);
1955         if (err)
1956                 goto out;
1957
1958         if (tb[IFLA_MTU])
1959                 ip6_tnl_change_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
1960
1961         dev_hold(dev);
1962
1963 out:
1964         return err;
1965 }
1966
1967 static int ip6gre_newlink(struct net *src_net, struct net_device *dev,
1968                           struct nlattr *tb[], struct nlattr *data[],
1969                           struct netlink_ext_ack *extack)
1970 {
1971         struct ip6_tnl *nt = netdev_priv(dev);
1972         struct net *net = dev_net(dev);
1973         struct ip6gre_net *ign;
1974         int err;
1975
1976         ip6gre_netlink_parms(data, &nt->parms);
1977         ign = net_generic(net, ip6gre_net_id);
1978
1979         if (nt->parms.collect_md) {
1980                 if (rtnl_dereference(ign->collect_md_tun))
1981                         return -EEXIST;
1982         } else {
1983                 if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
1984                         return -EEXIST;
1985         }
1986
1987         err = ip6gre_newlink_common(src_net, dev, tb, data, extack);
1988         if (!err) {
1989                 ip6gre_tnl_link_config(nt, !tb[IFLA_MTU]);
1990                 ip6gre_tunnel_link_md(ign, nt);
1991                 ip6gre_tunnel_link(net_generic(net, ip6gre_net_id), nt);
1992         }
1993         return err;
1994 }
1995
1996 static struct ip6_tnl *
1997 ip6gre_changelink_common(struct net_device *dev, struct nlattr *tb[],
1998                          struct nlattr *data[], struct __ip6_tnl_parm *p_p,
1999                          struct netlink_ext_ack *extack)
2000 {
2001         struct ip6_tnl *t, *nt = netdev_priv(dev);
2002         struct net *net = nt->net;
2003         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
2004         struct ip_tunnel_encap ipencap;
2005
2006         if (dev == ign->fb_tunnel_dev)
2007                 return ERR_PTR(-EINVAL);
2008
2009         if (ip6gre_netlink_encap_parms(data, &ipencap)) {
2010                 int err = ip6_tnl_encap_setup(nt, &ipencap);
2011
2012                 if (err < 0)
2013                         return ERR_PTR(err);
2014         }
2015
2016         ip6gre_netlink_parms(data, p_p);
2017
2018         t = ip6gre_tunnel_locate(net, p_p, 0);
2019
2020         if (t) {
2021                 if (t->dev != dev)
2022                         return ERR_PTR(-EEXIST);
2023         } else {
2024                 t = nt;
2025         }
2026
2027         return t;
2028 }
2029
2030 static int ip6gre_changelink(struct net_device *dev, struct nlattr *tb[],
2031                              struct nlattr *data[],
2032                              struct netlink_ext_ack *extack)
2033 {
2034         struct ip6_tnl *t = netdev_priv(dev);
2035         struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
2036         struct __ip6_tnl_parm p;
2037
2038         t = ip6gre_changelink_common(dev, tb, data, &p, extack);
2039         if (IS_ERR(t))
2040                 return PTR_ERR(t);
2041
2042         ip6gre_tunnel_unlink_md(ign, t);
2043         ip6gre_tunnel_unlink(ign, t);
2044         ip6gre_tnl_change(t, &p, !tb[IFLA_MTU]);
2045         ip6gre_tunnel_link_md(ign, t);
2046         ip6gre_tunnel_link(ign, t);
2047         return 0;
2048 }
2049
2050 static void ip6gre_dellink(struct net_device *dev, struct list_head *head)
2051 {
2052         struct net *net = dev_net(dev);
2053         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
2054
2055         if (dev != ign->fb_tunnel_dev)
2056                 unregister_netdevice_queue(dev, head);
2057 }
2058
2059 static size_t ip6gre_get_size(const struct net_device *dev)
2060 {
2061         return
2062                 /* IFLA_GRE_LINK */
2063                 nla_total_size(4) +
2064                 /* IFLA_GRE_IFLAGS */
2065                 nla_total_size(2) +
2066                 /* IFLA_GRE_OFLAGS */
2067                 nla_total_size(2) +
2068                 /* IFLA_GRE_IKEY */
2069                 nla_total_size(4) +
2070                 /* IFLA_GRE_OKEY */
2071                 nla_total_size(4) +
2072                 /* IFLA_GRE_LOCAL */
2073                 nla_total_size(sizeof(struct in6_addr)) +
2074                 /* IFLA_GRE_REMOTE */
2075                 nla_total_size(sizeof(struct in6_addr)) +
2076                 /* IFLA_GRE_TTL */
2077                 nla_total_size(1) +
2078                 /* IFLA_GRE_ENCAP_LIMIT */
2079                 nla_total_size(1) +
2080                 /* IFLA_GRE_FLOWINFO */
2081                 nla_total_size(4) +
2082                 /* IFLA_GRE_FLAGS */
2083                 nla_total_size(4) +
2084                 /* IFLA_GRE_ENCAP_TYPE */
2085                 nla_total_size(2) +
2086                 /* IFLA_GRE_ENCAP_FLAGS */
2087                 nla_total_size(2) +
2088                 /* IFLA_GRE_ENCAP_SPORT */
2089                 nla_total_size(2) +
2090                 /* IFLA_GRE_ENCAP_DPORT */
2091                 nla_total_size(2) +
2092                 /* IFLA_GRE_COLLECT_METADATA */
2093                 nla_total_size(0) +
2094                 /* IFLA_GRE_FWMARK */
2095                 nla_total_size(4) +
2096                 /* IFLA_GRE_ERSPAN_INDEX */
2097                 nla_total_size(4) +
2098                 0;
2099 }
2100
2101 static int ip6gre_fill_info(struct sk_buff *skb, const struct net_device *dev)
2102 {
2103         struct ip6_tnl *t = netdev_priv(dev);
2104         struct __ip6_tnl_parm *p = &t->parms;
2105         __be16 o_flags = p->o_flags;
2106
2107         if ((p->erspan_ver == 1 || p->erspan_ver == 2) &&
2108             !p->collect_md)
2109                 o_flags |= TUNNEL_KEY;
2110
2111         if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) ||
2112             nla_put_be16(skb, IFLA_GRE_IFLAGS,
2113                          gre_tnl_flags_to_gre_flags(p->i_flags)) ||
2114             nla_put_be16(skb, IFLA_GRE_OFLAGS,
2115                          gre_tnl_flags_to_gre_flags(o_flags)) ||
2116             nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) ||
2117             nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) ||
2118             nla_put_in6_addr(skb, IFLA_GRE_LOCAL, &p->laddr) ||
2119             nla_put_in6_addr(skb, IFLA_GRE_REMOTE, &p->raddr) ||
2120             nla_put_u8(skb, IFLA_GRE_TTL, p->hop_limit) ||
2121             nla_put_u8(skb, IFLA_GRE_ENCAP_LIMIT, p->encap_limit) ||
2122             nla_put_be32(skb, IFLA_GRE_FLOWINFO, p->flowinfo) ||
2123             nla_put_u32(skb, IFLA_GRE_FLAGS, p->flags) ||
2124             nla_put_u32(skb, IFLA_GRE_FWMARK, p->fwmark) ||
2125             nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, p->index))
2126                 goto nla_put_failure;
2127
2128         if (nla_put_u16(skb, IFLA_GRE_ENCAP_TYPE,
2129                         t->encap.type) ||
2130             nla_put_be16(skb, IFLA_GRE_ENCAP_SPORT,
2131                          t->encap.sport) ||
2132             nla_put_be16(skb, IFLA_GRE_ENCAP_DPORT,
2133                          t->encap.dport) ||
2134             nla_put_u16(skb, IFLA_GRE_ENCAP_FLAGS,
2135                         t->encap.flags))
2136                 goto nla_put_failure;
2137
2138         if (p->collect_md) {
2139                 if (nla_put_flag(skb, IFLA_GRE_COLLECT_METADATA))
2140                         goto nla_put_failure;
2141         }
2142
2143         if (nla_put_u8(skb, IFLA_GRE_ERSPAN_VER, p->erspan_ver))
2144                 goto nla_put_failure;
2145
2146         if (p->erspan_ver == 1) {
2147                 if (nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, p->index))
2148                         goto nla_put_failure;
2149         } else if (p->erspan_ver == 2) {
2150                 if (nla_put_u8(skb, IFLA_GRE_ERSPAN_DIR, p->dir))
2151                         goto nla_put_failure;
2152                 if (nla_put_u16(skb, IFLA_GRE_ERSPAN_HWID, p->hwid))
2153                         goto nla_put_failure;
2154         }
2155
2156         return 0;
2157
2158 nla_put_failure:
2159         return -EMSGSIZE;
2160 }
2161
2162 static const struct nla_policy ip6gre_policy[IFLA_GRE_MAX + 1] = {
2163         [IFLA_GRE_LINK]        = { .type = NLA_U32 },
2164         [IFLA_GRE_IFLAGS]      = { .type = NLA_U16 },
2165         [IFLA_GRE_OFLAGS]      = { .type = NLA_U16 },
2166         [IFLA_GRE_IKEY]        = { .type = NLA_U32 },
2167         [IFLA_GRE_OKEY]        = { .type = NLA_U32 },
2168         [IFLA_GRE_LOCAL]       = { .len = FIELD_SIZEOF(struct ipv6hdr, saddr) },
2169         [IFLA_GRE_REMOTE]      = { .len = FIELD_SIZEOF(struct ipv6hdr, daddr) },
2170         [IFLA_GRE_TTL]         = { .type = NLA_U8 },
2171         [IFLA_GRE_ENCAP_LIMIT] = { .type = NLA_U8 },
2172         [IFLA_GRE_FLOWINFO]    = { .type = NLA_U32 },
2173         [IFLA_GRE_FLAGS]       = { .type = NLA_U32 },
2174         [IFLA_GRE_ENCAP_TYPE]   = { .type = NLA_U16 },
2175         [IFLA_GRE_ENCAP_FLAGS]  = { .type = NLA_U16 },
2176         [IFLA_GRE_ENCAP_SPORT]  = { .type = NLA_U16 },
2177         [IFLA_GRE_ENCAP_DPORT]  = { .type = NLA_U16 },
2178         [IFLA_GRE_COLLECT_METADATA] = { .type = NLA_FLAG },
2179         [IFLA_GRE_FWMARK]       = { .type = NLA_U32 },
2180         [IFLA_GRE_ERSPAN_INDEX] = { .type = NLA_U32 },
2181         [IFLA_GRE_ERSPAN_VER]   = { .type = NLA_U8 },
2182         [IFLA_GRE_ERSPAN_DIR]   = { .type = NLA_U8 },
2183         [IFLA_GRE_ERSPAN_HWID]  = { .type = NLA_U16 },
2184 };
2185
2186 static void ip6erspan_tap_setup(struct net_device *dev)
2187 {
2188         ether_setup(dev);
2189
2190         dev->netdev_ops = &ip6erspan_netdev_ops;
2191         dev->needs_free_netdev = true;
2192         dev->priv_destructor = ip6gre_dev_free;
2193
2194         dev->features |= NETIF_F_NETNS_LOCAL;
2195         dev->priv_flags &= ~IFF_TX_SKB_SHARING;
2196         dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
2197         netif_keep_dst(dev);
2198 }
2199
2200 static int ip6erspan_newlink(struct net *src_net, struct net_device *dev,
2201                              struct nlattr *tb[], struct nlattr *data[],
2202                              struct netlink_ext_ack *extack)
2203 {
2204         struct ip6_tnl *nt = netdev_priv(dev);
2205         struct net *net = dev_net(dev);
2206         struct ip6gre_net *ign;
2207         int err;
2208
2209         ip6gre_netlink_parms(data, &nt->parms);
2210         ip6erspan_set_version(data, &nt->parms);
2211         ign = net_generic(net, ip6gre_net_id);
2212
2213         if (nt->parms.collect_md) {
2214                 if (rtnl_dereference(ign->collect_md_tun_erspan))
2215                         return -EEXIST;
2216         } else {
2217                 if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
2218                         return -EEXIST;
2219         }
2220
2221         err = ip6gre_newlink_common(src_net, dev, tb, data, extack);
2222         if (!err) {
2223                 ip6erspan_tnl_link_config(nt, !tb[IFLA_MTU]);
2224                 ip6erspan_tunnel_link_md(ign, nt);
2225                 ip6gre_tunnel_link(net_generic(net, ip6gre_net_id), nt);
2226         }
2227         return err;
2228 }
2229
2230 static void ip6erspan_tnl_link_config(struct ip6_tnl *t, int set_mtu)
2231 {
2232         ip6gre_tnl_link_config_common(t);
2233         ip6gre_tnl_link_config_route(t, set_mtu, ip6erspan_calc_hlen(t));
2234 }
2235
2236 static int ip6erspan_tnl_change(struct ip6_tnl *t,
2237                                 const struct __ip6_tnl_parm *p, int set_mtu)
2238 {
2239         ip6gre_tnl_copy_tnl_parm(t, p);
2240         ip6erspan_tnl_link_config(t, set_mtu);
2241         return 0;
2242 }
2243
2244 static int ip6erspan_changelink(struct net_device *dev, struct nlattr *tb[],
2245                                 struct nlattr *data[],
2246                                 struct netlink_ext_ack *extack)
2247 {
2248         struct ip6gre_net *ign = net_generic(dev_net(dev), ip6gre_net_id);
2249         struct __ip6_tnl_parm p;
2250         struct ip6_tnl *t;
2251
2252         t = ip6gre_changelink_common(dev, tb, data, &p, extack);
2253         if (IS_ERR(t))
2254                 return PTR_ERR(t);
2255
2256         ip6erspan_set_version(data, &p);
2257         ip6gre_tunnel_unlink_md(ign, t);
2258         ip6gre_tunnel_unlink(ign, t);
2259         ip6erspan_tnl_change(t, &p, !tb[IFLA_MTU]);
2260         ip6erspan_tunnel_link_md(ign, t);
2261         ip6gre_tunnel_link(ign, t);
2262         return 0;
2263 }
2264
2265 static struct rtnl_link_ops ip6gre_link_ops __read_mostly = {
2266         .kind           = "ip6gre",
2267         .maxtype        = IFLA_GRE_MAX,
2268         .policy         = ip6gre_policy,
2269         .priv_size      = sizeof(struct ip6_tnl),
2270         .setup          = ip6gre_tunnel_setup,
2271         .validate       = ip6gre_tunnel_validate,
2272         .newlink        = ip6gre_newlink,
2273         .changelink     = ip6gre_changelink,
2274         .dellink        = ip6gre_dellink,
2275         .get_size       = ip6gre_get_size,
2276         .fill_info      = ip6gre_fill_info,
2277         .get_link_net   = ip6_tnl_get_link_net,
2278 };
2279
2280 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly = {
2281         .kind           = "ip6gretap",
2282         .maxtype        = IFLA_GRE_MAX,
2283         .policy         = ip6gre_policy,
2284         .priv_size      = sizeof(struct ip6_tnl),
2285         .setup          = ip6gre_tap_setup,
2286         .validate       = ip6gre_tap_validate,
2287         .newlink        = ip6gre_newlink,
2288         .changelink     = ip6gre_changelink,
2289         .get_size       = ip6gre_get_size,
2290         .fill_info      = ip6gre_fill_info,
2291         .get_link_net   = ip6_tnl_get_link_net,
2292 };
2293
2294 static struct rtnl_link_ops ip6erspan_tap_ops __read_mostly = {
2295         .kind           = "ip6erspan",
2296         .maxtype        = IFLA_GRE_MAX,
2297         .policy         = ip6gre_policy,
2298         .priv_size      = sizeof(struct ip6_tnl),
2299         .setup          = ip6erspan_tap_setup,
2300         .validate       = ip6erspan_tap_validate,
2301         .newlink        = ip6erspan_newlink,
2302         .changelink     = ip6erspan_changelink,
2303         .get_size       = ip6gre_get_size,
2304         .fill_info      = ip6gre_fill_info,
2305         .get_link_net   = ip6_tnl_get_link_net,
2306 };
2307
2308 /*
2309  *      And now the modules code and kernel interface.
2310  */
2311
2312 static int __init ip6gre_init(void)
2313 {
2314         int err;
2315
2316         pr_info("GRE over IPv6 tunneling driver\n");
2317
2318         err = register_pernet_device(&ip6gre_net_ops);
2319         if (err < 0)
2320                 return err;
2321
2322         err = inet6_add_protocol(&ip6gre_protocol, IPPROTO_GRE);
2323         if (err < 0) {
2324                 pr_info("%s: can't add protocol\n", __func__);
2325                 goto add_proto_failed;
2326         }
2327
2328         err = rtnl_link_register(&ip6gre_link_ops);
2329         if (err < 0)
2330                 goto rtnl_link_failed;
2331
2332         err = rtnl_link_register(&ip6gre_tap_ops);
2333         if (err < 0)
2334                 goto tap_ops_failed;
2335
2336         err = rtnl_link_register(&ip6erspan_tap_ops);
2337         if (err < 0)
2338                 goto erspan_link_failed;
2339
2340 out:
2341         return err;
2342
2343 erspan_link_failed:
2344         rtnl_link_unregister(&ip6gre_tap_ops);
2345 tap_ops_failed:
2346         rtnl_link_unregister(&ip6gre_link_ops);
2347 rtnl_link_failed:
2348         inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
2349 add_proto_failed:
2350         unregister_pernet_device(&ip6gre_net_ops);
2351         goto out;
2352 }
2353
2354 static void __exit ip6gre_fini(void)
2355 {
2356         rtnl_link_unregister(&ip6gre_tap_ops);
2357         rtnl_link_unregister(&ip6gre_link_ops);
2358         rtnl_link_unregister(&ip6erspan_tap_ops);
2359         inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
2360         unregister_pernet_device(&ip6gre_net_ops);
2361 }
2362
2363 module_init(ip6gre_init);
2364 module_exit(ip6gre_fini);
2365 MODULE_LICENSE("GPL");
2366 MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)");
2367 MODULE_DESCRIPTION("GRE over IPv6 tunneling device");
2368 MODULE_ALIAS_RTNL_LINK("ip6gre");
2369 MODULE_ALIAS_RTNL_LINK("ip6gretap");
2370 MODULE_ALIAS_RTNL_LINK("ip6erspan");
2371 MODULE_ALIAS_NETDEV("ip6gre0");