Merge tag 'kvm-ppc-fixes-5.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git...
[platform/kernel/linux-starfive.git] / net / ipv6 / ip6_gre.c
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *      GRE over IPv6 protocol decoder.
4  *
5  *      Authors: Dmitry Kozlov (xeb@mail.ru)
6  */
7
8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9
10 #include <linux/capability.h>
11 #include <linux/module.h>
12 #include <linux/types.h>
13 #include <linux/kernel.h>
14 #include <linux/slab.h>
15 #include <linux/uaccess.h>
16 #include <linux/skbuff.h>
17 #include <linux/netdevice.h>
18 #include <linux/in.h>
19 #include <linux/tcp.h>
20 #include <linux/udp.h>
21 #include <linux/if_arp.h>
22 #include <linux/init.h>
23 #include <linux/in6.h>
24 #include <linux/inetdevice.h>
25 #include <linux/igmp.h>
26 #include <linux/netfilter_ipv4.h>
27 #include <linux/etherdevice.h>
28 #include <linux/if_ether.h>
29 #include <linux/hash.h>
30 #include <linux/if_tunnel.h>
31 #include <linux/ip6_tunnel.h>
32
33 #include <net/sock.h>
34 #include <net/ip.h>
35 #include <net/ip_tunnels.h>
36 #include <net/icmp.h>
37 #include <net/protocol.h>
38 #include <net/addrconf.h>
39 #include <net/arp.h>
40 #include <net/checksum.h>
41 #include <net/dsfield.h>
42 #include <net/inet_ecn.h>
43 #include <net/xfrm.h>
44 #include <net/net_namespace.h>
45 #include <net/netns/generic.h>
46 #include <net/rtnetlink.h>
47
48 #include <net/ipv6.h>
49 #include <net/ip6_fib.h>
50 #include <net/ip6_route.h>
51 #include <net/ip6_tunnel.h>
52 #include <net/gre.h>
53 #include <net/erspan.h>
54 #include <net/dst_metadata.h>
55
56
57 static bool log_ecn_error = true;
58 module_param(log_ecn_error, bool, 0644);
59 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
60
61 #define IP6_GRE_HASH_SIZE_SHIFT  5
62 #define IP6_GRE_HASH_SIZE (1 << IP6_GRE_HASH_SIZE_SHIFT)
63
64 static unsigned int ip6gre_net_id __read_mostly;
65 struct ip6gre_net {
66         struct ip6_tnl __rcu *tunnels[4][IP6_GRE_HASH_SIZE];
67
68         struct ip6_tnl __rcu *collect_md_tun;
69         struct ip6_tnl __rcu *collect_md_tun_erspan;
70         struct net_device *fb_tunnel_dev;
71 };
72
73 static struct rtnl_link_ops ip6gre_link_ops __read_mostly;
74 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly;
75 static struct rtnl_link_ops ip6erspan_tap_ops __read_mostly;
76 static int ip6gre_tunnel_init(struct net_device *dev);
77 static void ip6gre_tunnel_setup(struct net_device *dev);
78 static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t);
79 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu);
80 static void ip6erspan_tnl_link_config(struct ip6_tnl *t, int set_mtu);
81
82 /* Tunnel hash table */
83
84 /*
85    4 hash tables:
86
87    3: (remote,local)
88    2: (remote,*)
89    1: (*,local)
90    0: (*,*)
91
92    We require exact key match i.e. if a key is present in packet
93    it will match only tunnel with the same key; if it is not present,
94    it will match only keyless tunnel.
95
96    All keysless packets, if not matched configured keyless tunnels
97    will match fallback tunnel.
98  */
99
100 #define HASH_KEY(key) (((__force u32)key^((__force u32)key>>4))&(IP6_GRE_HASH_SIZE - 1))
101 static u32 HASH_ADDR(const struct in6_addr *addr)
102 {
103         u32 hash = ipv6_addr_hash(addr);
104
105         return hash_32(hash, IP6_GRE_HASH_SIZE_SHIFT);
106 }
107
108 #define tunnels_r_l     tunnels[3]
109 #define tunnels_r       tunnels[2]
110 #define tunnels_l       tunnels[1]
111 #define tunnels_wc      tunnels[0]
112
113 /* Given src, dst and key, find appropriate for input tunnel. */
114
115 static struct ip6_tnl *ip6gre_tunnel_lookup(struct net_device *dev,
116                 const struct in6_addr *remote, const struct in6_addr *local,
117                 __be32 key, __be16 gre_proto)
118 {
119         struct net *net = dev_net(dev);
120         int link = dev->ifindex;
121         unsigned int h0 = HASH_ADDR(remote);
122         unsigned int h1 = HASH_KEY(key);
123         struct ip6_tnl *t, *cand = NULL;
124         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
125         int dev_type = (gre_proto == htons(ETH_P_TEB) ||
126                         gre_proto == htons(ETH_P_ERSPAN) ||
127                         gre_proto == htons(ETH_P_ERSPAN2)) ?
128                        ARPHRD_ETHER : ARPHRD_IP6GRE;
129         int score, cand_score = 4;
130
131         for_each_ip_tunnel_rcu(t, ign->tunnels_r_l[h0 ^ h1]) {
132                 if (!ipv6_addr_equal(local, &t->parms.laddr) ||
133                     !ipv6_addr_equal(remote, &t->parms.raddr) ||
134                     key != t->parms.i_key ||
135                     !(t->dev->flags & IFF_UP))
136                         continue;
137
138                 if (t->dev->type != ARPHRD_IP6GRE &&
139                     t->dev->type != dev_type)
140                         continue;
141
142                 score = 0;
143                 if (t->parms.link != link)
144                         score |= 1;
145                 if (t->dev->type != dev_type)
146                         score |= 2;
147                 if (score == 0)
148                         return t;
149
150                 if (score < cand_score) {
151                         cand = t;
152                         cand_score = score;
153                 }
154         }
155
156         for_each_ip_tunnel_rcu(t, ign->tunnels_r[h0 ^ h1]) {
157                 if (!ipv6_addr_equal(remote, &t->parms.raddr) ||
158                     key != t->parms.i_key ||
159                     !(t->dev->flags & IFF_UP))
160                         continue;
161
162                 if (t->dev->type != ARPHRD_IP6GRE &&
163                     t->dev->type != dev_type)
164                         continue;
165
166                 score = 0;
167                 if (t->parms.link != link)
168                         score |= 1;
169                 if (t->dev->type != dev_type)
170                         score |= 2;
171                 if (score == 0)
172                         return t;
173
174                 if (score < cand_score) {
175                         cand = t;
176                         cand_score = score;
177                 }
178         }
179
180         for_each_ip_tunnel_rcu(t, ign->tunnels_l[h1]) {
181                 if ((!ipv6_addr_equal(local, &t->parms.laddr) &&
182                           (!ipv6_addr_equal(local, &t->parms.raddr) ||
183                                  !ipv6_addr_is_multicast(local))) ||
184                     key != t->parms.i_key ||
185                     !(t->dev->flags & IFF_UP))
186                         continue;
187
188                 if (t->dev->type != ARPHRD_IP6GRE &&
189                     t->dev->type != dev_type)
190                         continue;
191
192                 score = 0;
193                 if (t->parms.link != link)
194                         score |= 1;
195                 if (t->dev->type != dev_type)
196                         score |= 2;
197                 if (score == 0)
198                         return t;
199
200                 if (score < cand_score) {
201                         cand = t;
202                         cand_score = score;
203                 }
204         }
205
206         for_each_ip_tunnel_rcu(t, ign->tunnels_wc[h1]) {
207                 if (t->parms.i_key != key ||
208                     !(t->dev->flags & IFF_UP))
209                         continue;
210
211                 if (t->dev->type != ARPHRD_IP6GRE &&
212                     t->dev->type != dev_type)
213                         continue;
214
215                 score = 0;
216                 if (t->parms.link != link)
217                         score |= 1;
218                 if (t->dev->type != dev_type)
219                         score |= 2;
220                 if (score == 0)
221                         return t;
222
223                 if (score < cand_score) {
224                         cand = t;
225                         cand_score = score;
226                 }
227         }
228
229         if (cand)
230                 return cand;
231
232         if (gre_proto == htons(ETH_P_ERSPAN) ||
233             gre_proto == htons(ETH_P_ERSPAN2))
234                 t = rcu_dereference(ign->collect_md_tun_erspan);
235         else
236                 t = rcu_dereference(ign->collect_md_tun);
237
238         if (t && t->dev->flags & IFF_UP)
239                 return t;
240
241         dev = ign->fb_tunnel_dev;
242         if (dev && dev->flags & IFF_UP)
243                 return netdev_priv(dev);
244
245         return NULL;
246 }
247
248 static struct ip6_tnl __rcu **__ip6gre_bucket(struct ip6gre_net *ign,
249                 const struct __ip6_tnl_parm *p)
250 {
251         const struct in6_addr *remote = &p->raddr;
252         const struct in6_addr *local = &p->laddr;
253         unsigned int h = HASH_KEY(p->i_key);
254         int prio = 0;
255
256         if (!ipv6_addr_any(local))
257                 prio |= 1;
258         if (!ipv6_addr_any(remote) && !ipv6_addr_is_multicast(remote)) {
259                 prio |= 2;
260                 h ^= HASH_ADDR(remote);
261         }
262
263         return &ign->tunnels[prio][h];
264 }
265
266 static void ip6gre_tunnel_link_md(struct ip6gre_net *ign, struct ip6_tnl *t)
267 {
268         if (t->parms.collect_md)
269                 rcu_assign_pointer(ign->collect_md_tun, t);
270 }
271
272 static void ip6erspan_tunnel_link_md(struct ip6gre_net *ign, struct ip6_tnl *t)
273 {
274         if (t->parms.collect_md)
275                 rcu_assign_pointer(ign->collect_md_tun_erspan, t);
276 }
277
278 static void ip6gre_tunnel_unlink_md(struct ip6gre_net *ign, struct ip6_tnl *t)
279 {
280         if (t->parms.collect_md)
281                 rcu_assign_pointer(ign->collect_md_tun, NULL);
282 }
283
284 static void ip6erspan_tunnel_unlink_md(struct ip6gre_net *ign,
285                                        struct ip6_tnl *t)
286 {
287         if (t->parms.collect_md)
288                 rcu_assign_pointer(ign->collect_md_tun_erspan, NULL);
289 }
290
291 static inline struct ip6_tnl __rcu **ip6gre_bucket(struct ip6gre_net *ign,
292                 const struct ip6_tnl *t)
293 {
294         return __ip6gre_bucket(ign, &t->parms);
295 }
296
297 static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t)
298 {
299         struct ip6_tnl __rcu **tp = ip6gre_bucket(ign, t);
300
301         rcu_assign_pointer(t->next, rtnl_dereference(*tp));
302         rcu_assign_pointer(*tp, t);
303 }
304
305 static void ip6gre_tunnel_unlink(struct ip6gre_net *ign, struct ip6_tnl *t)
306 {
307         struct ip6_tnl __rcu **tp;
308         struct ip6_tnl *iter;
309
310         for (tp = ip6gre_bucket(ign, t);
311              (iter = rtnl_dereference(*tp)) != NULL;
312              tp = &iter->next) {
313                 if (t == iter) {
314                         rcu_assign_pointer(*tp, t->next);
315                         break;
316                 }
317         }
318 }
319
320 static struct ip6_tnl *ip6gre_tunnel_find(struct net *net,
321                                            const struct __ip6_tnl_parm *parms,
322                                            int type)
323 {
324         const struct in6_addr *remote = &parms->raddr;
325         const struct in6_addr *local = &parms->laddr;
326         __be32 key = parms->i_key;
327         int link = parms->link;
328         struct ip6_tnl *t;
329         struct ip6_tnl __rcu **tp;
330         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
331
332         for (tp = __ip6gre_bucket(ign, parms);
333              (t = rtnl_dereference(*tp)) != NULL;
334              tp = &t->next)
335                 if (ipv6_addr_equal(local, &t->parms.laddr) &&
336                     ipv6_addr_equal(remote, &t->parms.raddr) &&
337                     key == t->parms.i_key &&
338                     link == t->parms.link &&
339                     type == t->dev->type)
340                         break;
341
342         return t;
343 }
344
345 static struct ip6_tnl *ip6gre_tunnel_locate(struct net *net,
346                 const struct __ip6_tnl_parm *parms, int create)
347 {
348         struct ip6_tnl *t, *nt;
349         struct net_device *dev;
350         char name[IFNAMSIZ];
351         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
352
353         t = ip6gre_tunnel_find(net, parms, ARPHRD_IP6GRE);
354         if (t && create)
355                 return NULL;
356         if (t || !create)
357                 return t;
358
359         if (parms->name[0]) {
360                 if (!dev_valid_name(parms->name))
361                         return NULL;
362                 strlcpy(name, parms->name, IFNAMSIZ);
363         } else {
364                 strcpy(name, "ip6gre%d");
365         }
366         dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN,
367                            ip6gre_tunnel_setup);
368         if (!dev)
369                 return NULL;
370
371         dev_net_set(dev, net);
372
373         nt = netdev_priv(dev);
374         nt->parms = *parms;
375         dev->rtnl_link_ops = &ip6gre_link_ops;
376
377         nt->dev = dev;
378         nt->net = dev_net(dev);
379
380         if (register_netdevice(dev) < 0)
381                 goto failed_free;
382
383         ip6gre_tnl_link_config(nt, 1);
384
385         /* Can use a lockless transmit, unless we generate output sequences */
386         if (!(nt->parms.o_flags & TUNNEL_SEQ))
387                 dev->features |= NETIF_F_LLTX;
388
389         dev_hold(dev);
390         ip6gre_tunnel_link(ign, nt);
391         return nt;
392
393 failed_free:
394         free_netdev(dev);
395         return NULL;
396 }
397
398 static void ip6erspan_tunnel_uninit(struct net_device *dev)
399 {
400         struct ip6_tnl *t = netdev_priv(dev);
401         struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
402
403         ip6erspan_tunnel_unlink_md(ign, t);
404         ip6gre_tunnel_unlink(ign, t);
405         dst_cache_reset(&t->dst_cache);
406         dev_put(dev);
407 }
408
409 static void ip6gre_tunnel_uninit(struct net_device *dev)
410 {
411         struct ip6_tnl *t = netdev_priv(dev);
412         struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
413
414         ip6gre_tunnel_unlink_md(ign, t);
415         ip6gre_tunnel_unlink(ign, t);
416         dst_cache_reset(&t->dst_cache);
417         dev_put(dev);
418 }
419
420
421 static int ip6gre_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
422                        u8 type, u8 code, int offset, __be32 info)
423 {
424         struct net *net = dev_net(skb->dev);
425         const struct ipv6hdr *ipv6h;
426         struct tnl_ptk_info tpi;
427         struct ip6_tnl *t;
428
429         if (gre_parse_header(skb, &tpi, NULL, htons(ETH_P_IPV6),
430                              offset) < 0)
431                 return -EINVAL;
432
433         ipv6h = (const struct ipv6hdr *)skb->data;
434         t = ip6gre_tunnel_lookup(skb->dev, &ipv6h->daddr, &ipv6h->saddr,
435                                  tpi.key, tpi.proto);
436         if (!t)
437                 return -ENOENT;
438
439         switch (type) {
440                 struct ipv6_tlv_tnl_enc_lim *tel;
441                 __u32 teli;
442         case ICMPV6_DEST_UNREACH:
443                 net_dbg_ratelimited("%s: Path to destination invalid or inactive!\n",
444                                     t->parms.name);
445                 if (code != ICMPV6_PORT_UNREACH)
446                         break;
447                 return 0;
448         case ICMPV6_TIME_EXCEED:
449                 if (code == ICMPV6_EXC_HOPLIMIT) {
450                         net_dbg_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n",
451                                             t->parms.name);
452                         break;
453                 }
454                 return 0;
455         case ICMPV6_PARAMPROB:
456                 teli = 0;
457                 if (code == ICMPV6_HDR_FIELD)
458                         teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data);
459
460                 if (teli && teli == be32_to_cpu(info) - 2) {
461                         tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli];
462                         if (tel->encap_limit == 0) {
463                                 net_dbg_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n",
464                                                     t->parms.name);
465                         }
466                 } else {
467                         net_dbg_ratelimited("%s: Recipient unable to parse tunneled packet!\n",
468                                             t->parms.name);
469                 }
470                 return 0;
471         case ICMPV6_PKT_TOOBIG:
472                 ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL));
473                 return 0;
474         case NDISC_REDIRECT:
475                 ip6_redirect(skb, net, skb->dev->ifindex, 0,
476                              sock_net_uid(net, NULL));
477                 return 0;
478         }
479
480         if (time_before(jiffies, t->err_time + IP6TUNNEL_ERR_TIMEO))
481                 t->err_count++;
482         else
483                 t->err_count = 1;
484         t->err_time = jiffies;
485
486         return 0;
487 }
488
489 static int ip6gre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi)
490 {
491         const struct ipv6hdr *ipv6h;
492         struct ip6_tnl *tunnel;
493
494         ipv6h = ipv6_hdr(skb);
495         tunnel = ip6gre_tunnel_lookup(skb->dev,
496                                       &ipv6h->saddr, &ipv6h->daddr, tpi->key,
497                                       tpi->proto);
498         if (tunnel) {
499                 if (tunnel->parms.collect_md) {
500                         struct metadata_dst *tun_dst;
501                         __be64 tun_id;
502                         __be16 flags;
503
504                         flags = tpi->flags;
505                         tun_id = key32_to_tunnel_id(tpi->key);
506
507                         tun_dst = ipv6_tun_rx_dst(skb, flags, tun_id, 0);
508                         if (!tun_dst)
509                                 return PACKET_REJECT;
510
511                         ip6_tnl_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
512                 } else {
513                         ip6_tnl_rcv(tunnel, skb, tpi, NULL, log_ecn_error);
514                 }
515
516                 return PACKET_RCVD;
517         }
518
519         return PACKET_REJECT;
520 }
521
522 static int ip6erspan_rcv(struct sk_buff *skb,
523                          struct tnl_ptk_info *tpi,
524                          int gre_hdr_len)
525 {
526         struct erspan_base_hdr *ershdr;
527         const struct ipv6hdr *ipv6h;
528         struct erspan_md2 *md2;
529         struct ip6_tnl *tunnel;
530         u8 ver;
531
532         ipv6h = ipv6_hdr(skb);
533         ershdr = (struct erspan_base_hdr *)skb->data;
534         ver = ershdr->ver;
535
536         tunnel = ip6gre_tunnel_lookup(skb->dev,
537                                       &ipv6h->saddr, &ipv6h->daddr, tpi->key,
538                                       tpi->proto);
539         if (tunnel) {
540                 int len = erspan_hdr_len(ver);
541
542                 if (unlikely(!pskb_may_pull(skb, len)))
543                         return PACKET_REJECT;
544
545                 if (__iptunnel_pull_header(skb, len,
546                                            htons(ETH_P_TEB),
547                                            false, false) < 0)
548                         return PACKET_REJECT;
549
550                 if (tunnel->parms.collect_md) {
551                         struct erspan_metadata *pkt_md, *md;
552                         struct metadata_dst *tun_dst;
553                         struct ip_tunnel_info *info;
554                         unsigned char *gh;
555                         __be64 tun_id;
556                         __be16 flags;
557
558                         tpi->flags |= TUNNEL_KEY;
559                         flags = tpi->flags;
560                         tun_id = key32_to_tunnel_id(tpi->key);
561
562                         tun_dst = ipv6_tun_rx_dst(skb, flags, tun_id,
563                                                   sizeof(*md));
564                         if (!tun_dst)
565                                 return PACKET_REJECT;
566
567                         /* skb can be uncloned in __iptunnel_pull_header, so
568                          * old pkt_md is no longer valid and we need to reset
569                          * it
570                          */
571                         gh = skb_network_header(skb) +
572                              skb_network_header_len(skb);
573                         pkt_md = (struct erspan_metadata *)(gh + gre_hdr_len +
574                                                             sizeof(*ershdr));
575                         info = &tun_dst->u.tun_info;
576                         md = ip_tunnel_info_opts(info);
577                         md->version = ver;
578                         md2 = &md->u.md2;
579                         memcpy(md2, pkt_md, ver == 1 ? ERSPAN_V1_MDSIZE :
580                                                        ERSPAN_V2_MDSIZE);
581                         info->key.tun_flags |= TUNNEL_ERSPAN_OPT;
582                         info->options_len = sizeof(*md);
583
584                         ip6_tnl_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
585
586                 } else {
587                         ip6_tnl_rcv(tunnel, skb, tpi, NULL, log_ecn_error);
588                 }
589
590                 return PACKET_RCVD;
591         }
592
593         return PACKET_REJECT;
594 }
595
596 static int gre_rcv(struct sk_buff *skb)
597 {
598         struct tnl_ptk_info tpi;
599         bool csum_err = false;
600         int hdr_len;
601
602         hdr_len = gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IPV6), 0);
603         if (hdr_len < 0)
604                 goto drop;
605
606         if (iptunnel_pull_header(skb, hdr_len, tpi.proto, false))
607                 goto drop;
608
609         if (unlikely(tpi.proto == htons(ETH_P_ERSPAN) ||
610                      tpi.proto == htons(ETH_P_ERSPAN2))) {
611                 if (ip6erspan_rcv(skb, &tpi, hdr_len) == PACKET_RCVD)
612                         return 0;
613                 goto out;
614         }
615
616         if (ip6gre_rcv(skb, &tpi) == PACKET_RCVD)
617                 return 0;
618
619 out:
620         icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
621 drop:
622         kfree_skb(skb);
623         return 0;
624 }
625
626 static int gre_handle_offloads(struct sk_buff *skb, bool csum)
627 {
628         return iptunnel_handle_offloads(skb,
629                                         csum ? SKB_GSO_GRE_CSUM : SKB_GSO_GRE);
630 }
631
632 static void prepare_ip6gre_xmit_ipv4(struct sk_buff *skb,
633                                      struct net_device *dev,
634                                      struct flowi6 *fl6, __u8 *dsfield,
635                                      int *encap_limit)
636 {
637         const struct iphdr *iph = ip_hdr(skb);
638         struct ip6_tnl *t = netdev_priv(dev);
639
640         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
641                 *encap_limit = t->parms.encap_limit;
642
643         memcpy(fl6, &t->fl.u.ip6, sizeof(*fl6));
644
645         if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
646                 *dsfield = ipv4_get_dsfield(iph);
647         else
648                 *dsfield = ip6_tclass(t->parms.flowinfo);
649
650         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
651                 fl6->flowi6_mark = skb->mark;
652         else
653                 fl6->flowi6_mark = t->parms.fwmark;
654
655         fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
656 }
657
658 static int prepare_ip6gre_xmit_ipv6(struct sk_buff *skb,
659                                     struct net_device *dev,
660                                     struct flowi6 *fl6, __u8 *dsfield,
661                                     int *encap_limit)
662 {
663         struct ipv6hdr *ipv6h;
664         struct ip6_tnl *t = netdev_priv(dev);
665         __u16 offset;
666
667         offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb));
668         /* ip6_tnl_parse_tlv_enc_lim() might have reallocated skb->head */
669         ipv6h = ipv6_hdr(skb);
670
671         if (offset > 0) {
672                 struct ipv6_tlv_tnl_enc_lim *tel;
673
674                 tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset];
675                 if (tel->encap_limit == 0) {
676                         icmpv6_send(skb, ICMPV6_PARAMPROB,
677                                     ICMPV6_HDR_FIELD, offset + 2);
678                         return -1;
679                 }
680                 *encap_limit = tel->encap_limit - 1;
681         } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) {
682                 *encap_limit = t->parms.encap_limit;
683         }
684
685         memcpy(fl6, &t->fl.u.ip6, sizeof(*fl6));
686
687         if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
688                 *dsfield = ipv6_get_dsfield(ipv6h);
689         else
690                 *dsfield = ip6_tclass(t->parms.flowinfo);
691
692         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)
693                 fl6->flowlabel |= ip6_flowlabel(ipv6h);
694
695         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
696                 fl6->flowi6_mark = skb->mark;
697         else
698                 fl6->flowi6_mark = t->parms.fwmark;
699
700         fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
701
702         return 0;
703 }
704
705 static netdev_tx_t __gre6_xmit(struct sk_buff *skb,
706                                struct net_device *dev, __u8 dsfield,
707                                struct flowi6 *fl6, int encap_limit,
708                                __u32 *pmtu, __be16 proto)
709 {
710         struct ip6_tnl *tunnel = netdev_priv(dev);
711         __be16 protocol;
712
713         if (dev->type == ARPHRD_ETHER)
714                 IPCB(skb)->flags = 0;
715
716         if (dev->header_ops && dev->type == ARPHRD_IP6GRE)
717                 fl6->daddr = ((struct ipv6hdr *)skb->data)->daddr;
718         else
719                 fl6->daddr = tunnel->parms.raddr;
720
721         if (skb_cow_head(skb, dev->needed_headroom ?: tunnel->hlen))
722                 return -ENOMEM;
723
724         /* Push GRE header. */
725         protocol = (dev->type == ARPHRD_ETHER) ? htons(ETH_P_TEB) : proto;
726
727         if (tunnel->parms.collect_md) {
728                 struct ip_tunnel_info *tun_info;
729                 const struct ip_tunnel_key *key;
730                 __be16 flags;
731
732                 tun_info = skb_tunnel_info(skb);
733                 if (unlikely(!tun_info ||
734                              !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
735                              ip_tunnel_info_af(tun_info) != AF_INET6))
736                         return -EINVAL;
737
738                 key = &tun_info->key;
739                 memset(fl6, 0, sizeof(*fl6));
740                 fl6->flowi6_proto = IPPROTO_GRE;
741                 fl6->daddr = key->u.ipv6.dst;
742                 fl6->flowlabel = key->label;
743                 fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
744
745                 dsfield = key->tos;
746                 flags = key->tun_flags &
747                         (TUNNEL_CSUM | TUNNEL_KEY | TUNNEL_SEQ);
748                 tunnel->tun_hlen = gre_calc_hlen(flags);
749
750                 gre_build_header(skb, tunnel->tun_hlen,
751                                  flags, protocol,
752                                  tunnel_id_to_key32(tun_info->key.tun_id),
753                                  (flags & TUNNEL_SEQ) ? htonl(tunnel->o_seqno++)
754                                                       : 0);
755
756         } else {
757                 if (tunnel->parms.o_flags & TUNNEL_SEQ)
758                         tunnel->o_seqno++;
759
760                 gre_build_header(skb, tunnel->tun_hlen, tunnel->parms.o_flags,
761                                  protocol, tunnel->parms.o_key,
762                                  htonl(tunnel->o_seqno));
763         }
764
765         return ip6_tnl_xmit(skb, dev, dsfield, fl6, encap_limit, pmtu,
766                             NEXTHDR_GRE);
767 }
768
769 static inline int ip6gre_xmit_ipv4(struct sk_buff *skb, struct net_device *dev)
770 {
771         struct ip6_tnl *t = netdev_priv(dev);
772         int encap_limit = -1;
773         struct flowi6 fl6;
774         __u8 dsfield = 0;
775         __u32 mtu;
776         int err;
777
778         memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
779
780         if (!t->parms.collect_md)
781                 prepare_ip6gre_xmit_ipv4(skb, dev, &fl6,
782                                          &dsfield, &encap_limit);
783
784         err = gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM));
785         if (err)
786                 return -1;
787
788         err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
789                           skb->protocol);
790         if (err != 0) {
791                 /* XXX: send ICMP error even if DF is not set. */
792                 if (err == -EMSGSIZE)
793                         icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
794                                   htonl(mtu));
795                 return -1;
796         }
797
798         return 0;
799 }
800
801 static inline int ip6gre_xmit_ipv6(struct sk_buff *skb, struct net_device *dev)
802 {
803         struct ip6_tnl *t = netdev_priv(dev);
804         struct ipv6hdr *ipv6h = ipv6_hdr(skb);
805         int encap_limit = -1;
806         struct flowi6 fl6;
807         __u8 dsfield = 0;
808         __u32 mtu;
809         int err;
810
811         if (ipv6_addr_equal(&t->parms.raddr, &ipv6h->saddr))
812                 return -1;
813
814         if (!t->parms.collect_md &&
815             prepare_ip6gre_xmit_ipv6(skb, dev, &fl6, &dsfield, &encap_limit))
816                 return -1;
817
818         if (gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM)))
819                 return -1;
820
821         err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit,
822                           &mtu, skb->protocol);
823         if (err != 0) {
824                 if (err == -EMSGSIZE)
825                         icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
826                 return -1;
827         }
828
829         return 0;
830 }
831
832 /**
833  * ip6gre_tnl_addr_conflict - compare packet addresses to tunnel's own
834  *   @t: the outgoing tunnel device
835  *   @hdr: IPv6 header from the incoming packet
836  *
837  * Description:
838  *   Avoid trivial tunneling loop by checking that tunnel exit-point
839  *   doesn't match source of incoming packet.
840  *
841  * Return:
842  *   1 if conflict,
843  *   0 else
844  **/
845
846 static inline bool ip6gre_tnl_addr_conflict(const struct ip6_tnl *t,
847         const struct ipv6hdr *hdr)
848 {
849         return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
850 }
851
852 static int ip6gre_xmit_other(struct sk_buff *skb, struct net_device *dev)
853 {
854         struct ip6_tnl *t = netdev_priv(dev);
855         int encap_limit = -1;
856         struct flowi6 fl6;
857         __u32 mtu;
858         int err;
859
860         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
861                 encap_limit = t->parms.encap_limit;
862
863         if (!t->parms.collect_md)
864                 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
865
866         err = gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM));
867         if (err)
868                 return err;
869
870         err = __gre6_xmit(skb, dev, 0, &fl6, encap_limit, &mtu, skb->protocol);
871
872         return err;
873 }
874
875 static netdev_tx_t ip6gre_tunnel_xmit(struct sk_buff *skb,
876         struct net_device *dev)
877 {
878         struct ip6_tnl *t = netdev_priv(dev);
879         struct net_device_stats *stats = &t->dev->stats;
880         int ret;
881
882         if (!pskb_inet_may_pull(skb))
883                 goto tx_err;
884
885         if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr))
886                 goto tx_err;
887
888         switch (skb->protocol) {
889         case htons(ETH_P_IP):
890                 ret = ip6gre_xmit_ipv4(skb, dev);
891                 break;
892         case htons(ETH_P_IPV6):
893                 ret = ip6gre_xmit_ipv6(skb, dev);
894                 break;
895         default:
896                 ret = ip6gre_xmit_other(skb, dev);
897                 break;
898         }
899
900         if (ret < 0)
901                 goto tx_err;
902
903         return NETDEV_TX_OK;
904
905 tx_err:
906         stats->tx_errors++;
907         stats->tx_dropped++;
908         kfree_skb(skb);
909         return NETDEV_TX_OK;
910 }
911
912 static netdev_tx_t ip6erspan_tunnel_xmit(struct sk_buff *skb,
913                                          struct net_device *dev)
914 {
915         struct ip6_tnl *t = netdev_priv(dev);
916         struct dst_entry *dst = skb_dst(skb);
917         struct net_device_stats *stats;
918         bool truncate = false;
919         int encap_limit = -1;
920         __u8 dsfield = false;
921         struct flowi6 fl6;
922         int err = -EINVAL;
923         __be16 proto;
924         __u32 mtu;
925         int nhoff;
926         int thoff;
927
928         if (!pskb_inet_may_pull(skb))
929                 goto tx_err;
930
931         if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr))
932                 goto tx_err;
933
934         if (gre_handle_offloads(skb, false))
935                 goto tx_err;
936
937         if (skb->len > dev->mtu + dev->hard_header_len) {
938                 pskb_trim(skb, dev->mtu + dev->hard_header_len);
939                 truncate = true;
940         }
941
942         nhoff = skb_network_header(skb) - skb_mac_header(skb);
943         if (skb->protocol == htons(ETH_P_IP) &&
944             (ntohs(ip_hdr(skb)->tot_len) > skb->len - nhoff))
945                 truncate = true;
946
947         thoff = skb_transport_header(skb) - skb_mac_header(skb);
948         if (skb->protocol == htons(ETH_P_IPV6) &&
949             (ntohs(ipv6_hdr(skb)->payload_len) > skb->len - thoff))
950                 truncate = true;
951
952         if (skb_cow_head(skb, dev->needed_headroom ?: t->hlen))
953                 goto tx_err;
954
955         t->parms.o_flags &= ~TUNNEL_KEY;
956         IPCB(skb)->flags = 0;
957
958         /* For collect_md mode, derive fl6 from the tunnel key,
959          * for native mode, call prepare_ip6gre_xmit_{ipv4,ipv6}.
960          */
961         if (t->parms.collect_md) {
962                 struct ip_tunnel_info *tun_info;
963                 const struct ip_tunnel_key *key;
964                 struct erspan_metadata *md;
965                 __be32 tun_id;
966
967                 tun_info = skb_tunnel_info(skb);
968                 if (unlikely(!tun_info ||
969                              !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
970                              ip_tunnel_info_af(tun_info) != AF_INET6))
971                         goto tx_err;
972
973                 key = &tun_info->key;
974                 memset(&fl6, 0, sizeof(fl6));
975                 fl6.flowi6_proto = IPPROTO_GRE;
976                 fl6.daddr = key->u.ipv6.dst;
977                 fl6.flowlabel = key->label;
978                 fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL);
979
980                 dsfield = key->tos;
981                 if (!(tun_info->key.tun_flags & TUNNEL_ERSPAN_OPT))
982                         goto tx_err;
983                 md = ip_tunnel_info_opts(tun_info);
984                 if (!md)
985                         goto tx_err;
986
987                 tun_id = tunnel_id_to_key32(key->tun_id);
988                 if (md->version == 1) {
989                         erspan_build_header(skb,
990                                             ntohl(tun_id),
991                                             ntohl(md->u.index), truncate,
992                                             false);
993                 } else if (md->version == 2) {
994                         erspan_build_header_v2(skb,
995                                                ntohl(tun_id),
996                                                md->u.md2.dir,
997                                                get_hwid(&md->u.md2),
998                                                truncate, false);
999                 } else {
1000                         goto tx_err;
1001                 }
1002         } else {
1003                 switch (skb->protocol) {
1004                 case htons(ETH_P_IP):
1005                         memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
1006                         prepare_ip6gre_xmit_ipv4(skb, dev, &fl6,
1007                                                  &dsfield, &encap_limit);
1008                         break;
1009                 case htons(ETH_P_IPV6):
1010                         if (ipv6_addr_equal(&t->parms.raddr, &ipv6_hdr(skb)->saddr))
1011                                 goto tx_err;
1012                         if (prepare_ip6gre_xmit_ipv6(skb, dev, &fl6,
1013                                                      &dsfield, &encap_limit))
1014                                 goto tx_err;
1015                         break;
1016                 default:
1017                         memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
1018                         break;
1019                 }
1020
1021                 if (t->parms.erspan_ver == 1)
1022                         erspan_build_header(skb, ntohl(t->parms.o_key),
1023                                             t->parms.index,
1024                                             truncate, false);
1025                 else if (t->parms.erspan_ver == 2)
1026                         erspan_build_header_v2(skb, ntohl(t->parms.o_key),
1027                                                t->parms.dir,
1028                                                t->parms.hwid,
1029                                                truncate, false);
1030                 else
1031                         goto tx_err;
1032
1033                 fl6.daddr = t->parms.raddr;
1034         }
1035
1036         /* Push GRE header. */
1037         proto = (t->parms.erspan_ver == 1) ? htons(ETH_P_ERSPAN)
1038                                            : htons(ETH_P_ERSPAN2);
1039         gre_build_header(skb, 8, TUNNEL_SEQ, proto, 0, htonl(t->o_seqno++));
1040
1041         /* TooBig packet may have updated dst->dev's mtu */
1042         if (!t->parms.collect_md && dst && dst_mtu(dst) > dst->dev->mtu)
1043                 dst->ops->update_pmtu(dst, NULL, skb, dst->dev->mtu);
1044
1045         err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
1046                            NEXTHDR_GRE);
1047         if (err != 0) {
1048                 /* XXX: send ICMP error even if DF is not set. */
1049                 if (err == -EMSGSIZE) {
1050                         if (skb->protocol == htons(ETH_P_IP))
1051                                 icmp_send(skb, ICMP_DEST_UNREACH,
1052                                           ICMP_FRAG_NEEDED, htonl(mtu));
1053                         else
1054                                 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
1055                 }
1056
1057                 goto tx_err;
1058         }
1059         return NETDEV_TX_OK;
1060
1061 tx_err:
1062         stats = &t->dev->stats;
1063         stats->tx_errors++;
1064         stats->tx_dropped++;
1065         kfree_skb(skb);
1066         return NETDEV_TX_OK;
1067 }
1068
1069 static void ip6gre_tnl_link_config_common(struct ip6_tnl *t)
1070 {
1071         struct net_device *dev = t->dev;
1072         struct __ip6_tnl_parm *p = &t->parms;
1073         struct flowi6 *fl6 = &t->fl.u.ip6;
1074
1075         if (dev->type != ARPHRD_ETHER) {
1076                 memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr));
1077                 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
1078         }
1079
1080         /* Set up flowi template */
1081         fl6->saddr = p->laddr;
1082         fl6->daddr = p->raddr;
1083         fl6->flowi6_oif = p->link;
1084         fl6->flowlabel = 0;
1085         fl6->flowi6_proto = IPPROTO_GRE;
1086
1087         if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS))
1088                 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo;
1089         if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL))
1090                 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo;
1091
1092         p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET);
1093         p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
1094
1095         if (p->flags&IP6_TNL_F_CAP_XMIT &&
1096                         p->flags&IP6_TNL_F_CAP_RCV && dev->type != ARPHRD_ETHER)
1097                 dev->flags |= IFF_POINTOPOINT;
1098         else
1099                 dev->flags &= ~IFF_POINTOPOINT;
1100 }
1101
1102 static void ip6gre_tnl_link_config_route(struct ip6_tnl *t, int set_mtu,
1103                                          int t_hlen)
1104 {
1105         const struct __ip6_tnl_parm *p = &t->parms;
1106         struct net_device *dev = t->dev;
1107
1108         if (p->flags & IP6_TNL_F_CAP_XMIT) {
1109                 int strict = (ipv6_addr_type(&p->raddr) &
1110                               (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL));
1111
1112                 struct rt6_info *rt = rt6_lookup(t->net,
1113                                                  &p->raddr, &p->laddr,
1114                                                  p->link, NULL, strict);
1115
1116                 if (!rt)
1117                         return;
1118
1119                 if (rt->dst.dev) {
1120                         dev->needed_headroom = rt->dst.dev->hard_header_len +
1121                                                t_hlen;
1122
1123                         if (set_mtu) {
1124                                 dev->mtu = rt->dst.dev->mtu - t_hlen;
1125                                 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1126                                         dev->mtu -= 8;
1127                                 if (dev->type == ARPHRD_ETHER)
1128                                         dev->mtu -= ETH_HLEN;
1129
1130                                 if (dev->mtu < IPV6_MIN_MTU)
1131                                         dev->mtu = IPV6_MIN_MTU;
1132                         }
1133                 }
1134                 ip6_rt_put(rt);
1135         }
1136 }
1137
1138 static int ip6gre_calc_hlen(struct ip6_tnl *tunnel)
1139 {
1140         int t_hlen;
1141
1142         tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags);
1143         tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen;
1144
1145         t_hlen = tunnel->hlen + sizeof(struct ipv6hdr);
1146         tunnel->dev->needed_headroom = LL_MAX_HEADER + t_hlen;
1147         return t_hlen;
1148 }
1149
1150 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu)
1151 {
1152         ip6gre_tnl_link_config_common(t);
1153         ip6gre_tnl_link_config_route(t, set_mtu, ip6gre_calc_hlen(t));
1154 }
1155
1156 static void ip6gre_tnl_copy_tnl_parm(struct ip6_tnl *t,
1157                                      const struct __ip6_tnl_parm *p)
1158 {
1159         t->parms.laddr = p->laddr;
1160         t->parms.raddr = p->raddr;
1161         t->parms.flags = p->flags;
1162         t->parms.hop_limit = p->hop_limit;
1163         t->parms.encap_limit = p->encap_limit;
1164         t->parms.flowinfo = p->flowinfo;
1165         t->parms.link = p->link;
1166         t->parms.proto = p->proto;
1167         t->parms.i_key = p->i_key;
1168         t->parms.o_key = p->o_key;
1169         t->parms.i_flags = p->i_flags;
1170         t->parms.o_flags = p->o_flags;
1171         t->parms.fwmark = p->fwmark;
1172         t->parms.erspan_ver = p->erspan_ver;
1173         t->parms.index = p->index;
1174         t->parms.dir = p->dir;
1175         t->parms.hwid = p->hwid;
1176         dst_cache_reset(&t->dst_cache);
1177 }
1178
1179 static int ip6gre_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p,
1180                              int set_mtu)
1181 {
1182         ip6gre_tnl_copy_tnl_parm(t, p);
1183         ip6gre_tnl_link_config(t, set_mtu);
1184         return 0;
1185 }
1186
1187 static void ip6gre_tnl_parm_from_user(struct __ip6_tnl_parm *p,
1188         const struct ip6_tnl_parm2 *u)
1189 {
1190         p->laddr = u->laddr;
1191         p->raddr = u->raddr;
1192         p->flags = u->flags;
1193         p->hop_limit = u->hop_limit;
1194         p->encap_limit = u->encap_limit;
1195         p->flowinfo = u->flowinfo;
1196         p->link = u->link;
1197         p->i_key = u->i_key;
1198         p->o_key = u->o_key;
1199         p->i_flags = gre_flags_to_tnl_flags(u->i_flags);
1200         p->o_flags = gre_flags_to_tnl_flags(u->o_flags);
1201         memcpy(p->name, u->name, sizeof(u->name));
1202 }
1203
1204 static void ip6gre_tnl_parm_to_user(struct ip6_tnl_parm2 *u,
1205         const struct __ip6_tnl_parm *p)
1206 {
1207         u->proto = IPPROTO_GRE;
1208         u->laddr = p->laddr;
1209         u->raddr = p->raddr;
1210         u->flags = p->flags;
1211         u->hop_limit = p->hop_limit;
1212         u->encap_limit = p->encap_limit;
1213         u->flowinfo = p->flowinfo;
1214         u->link = p->link;
1215         u->i_key = p->i_key;
1216         u->o_key = p->o_key;
1217         u->i_flags = gre_tnl_flags_to_gre_flags(p->i_flags);
1218         u->o_flags = gre_tnl_flags_to_gre_flags(p->o_flags);
1219         memcpy(u->name, p->name, sizeof(u->name));
1220 }
1221
1222 static int ip6gre_tunnel_ioctl(struct net_device *dev,
1223         struct ifreq *ifr, int cmd)
1224 {
1225         int err = 0;
1226         struct ip6_tnl_parm2 p;
1227         struct __ip6_tnl_parm p1;
1228         struct ip6_tnl *t = netdev_priv(dev);
1229         struct net *net = t->net;
1230         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1231
1232         memset(&p1, 0, sizeof(p1));
1233
1234         switch (cmd) {
1235         case SIOCGETTUNNEL:
1236                 if (dev == ign->fb_tunnel_dev) {
1237                         if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
1238                                 err = -EFAULT;
1239                                 break;
1240                         }
1241                         ip6gre_tnl_parm_from_user(&p1, &p);
1242                         t = ip6gre_tunnel_locate(net, &p1, 0);
1243                         if (!t)
1244                                 t = netdev_priv(dev);
1245                 }
1246                 memset(&p, 0, sizeof(p));
1247                 ip6gre_tnl_parm_to_user(&p, &t->parms);
1248                 if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
1249                         err = -EFAULT;
1250                 break;
1251
1252         case SIOCADDTUNNEL:
1253         case SIOCCHGTUNNEL:
1254                 err = -EPERM;
1255                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1256                         goto done;
1257
1258                 err = -EFAULT;
1259                 if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1260                         goto done;
1261
1262                 err = -EINVAL;
1263                 if ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING))
1264                         goto done;
1265
1266                 if (!(p.i_flags&GRE_KEY))
1267                         p.i_key = 0;
1268                 if (!(p.o_flags&GRE_KEY))
1269                         p.o_key = 0;
1270
1271                 ip6gre_tnl_parm_from_user(&p1, &p);
1272                 t = ip6gre_tunnel_locate(net, &p1, cmd == SIOCADDTUNNEL);
1273
1274                 if (dev != ign->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
1275                         if (t) {
1276                                 if (t->dev != dev) {
1277                                         err = -EEXIST;
1278                                         break;
1279                                 }
1280                         } else {
1281                                 t = netdev_priv(dev);
1282
1283                                 ip6gre_tunnel_unlink(ign, t);
1284                                 synchronize_net();
1285                                 ip6gre_tnl_change(t, &p1, 1);
1286                                 ip6gre_tunnel_link(ign, t);
1287                                 netdev_state_change(dev);
1288                         }
1289                 }
1290
1291                 if (t) {
1292                         err = 0;
1293
1294                         memset(&p, 0, sizeof(p));
1295                         ip6gre_tnl_parm_to_user(&p, &t->parms);
1296                         if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
1297                                 err = -EFAULT;
1298                 } else
1299                         err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
1300                 break;
1301
1302         case SIOCDELTUNNEL:
1303                 err = -EPERM;
1304                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1305                         goto done;
1306
1307                 if (dev == ign->fb_tunnel_dev) {
1308                         err = -EFAULT;
1309                         if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
1310                                 goto done;
1311                         err = -ENOENT;
1312                         ip6gre_tnl_parm_from_user(&p1, &p);
1313                         t = ip6gre_tunnel_locate(net, &p1, 0);
1314                         if (!t)
1315                                 goto done;
1316                         err = -EPERM;
1317                         if (t == netdev_priv(ign->fb_tunnel_dev))
1318                                 goto done;
1319                         dev = t->dev;
1320                 }
1321                 unregister_netdevice(dev);
1322                 err = 0;
1323                 break;
1324
1325         default:
1326                 err = -EINVAL;
1327         }
1328
1329 done:
1330         return err;
1331 }
1332
1333 static int ip6gre_header(struct sk_buff *skb, struct net_device *dev,
1334                          unsigned short type, const void *daddr,
1335                          const void *saddr, unsigned int len)
1336 {
1337         struct ip6_tnl *t = netdev_priv(dev);
1338         struct ipv6hdr *ipv6h;
1339         __be16 *p;
1340
1341         ipv6h = skb_push(skb, t->hlen + sizeof(*ipv6h));
1342         ip6_flow_hdr(ipv6h, 0, ip6_make_flowlabel(dev_net(dev), skb,
1343                                                   t->fl.u.ip6.flowlabel,
1344                                                   true, &t->fl.u.ip6));
1345         ipv6h->hop_limit = t->parms.hop_limit;
1346         ipv6h->nexthdr = NEXTHDR_GRE;
1347         ipv6h->saddr = t->parms.laddr;
1348         ipv6h->daddr = t->parms.raddr;
1349
1350         p = (__be16 *)(ipv6h + 1);
1351         p[0] = t->parms.o_flags;
1352         p[1] = htons(type);
1353
1354         /*
1355          *      Set the source hardware address.
1356          */
1357
1358         if (saddr)
1359                 memcpy(&ipv6h->saddr, saddr, sizeof(struct in6_addr));
1360         if (daddr)
1361                 memcpy(&ipv6h->daddr, daddr, sizeof(struct in6_addr));
1362         if (!ipv6_addr_any(&ipv6h->daddr))
1363                 return t->hlen;
1364
1365         return -t->hlen;
1366 }
1367
1368 static const struct header_ops ip6gre_header_ops = {
1369         .create = ip6gre_header,
1370 };
1371
1372 static const struct net_device_ops ip6gre_netdev_ops = {
1373         .ndo_init               = ip6gre_tunnel_init,
1374         .ndo_uninit             = ip6gre_tunnel_uninit,
1375         .ndo_start_xmit         = ip6gre_tunnel_xmit,
1376         .ndo_do_ioctl           = ip6gre_tunnel_ioctl,
1377         .ndo_change_mtu         = ip6_tnl_change_mtu,
1378         .ndo_get_stats64        = ip_tunnel_get_stats64,
1379         .ndo_get_iflink         = ip6_tnl_get_iflink,
1380 };
1381
1382 static void ip6gre_dev_free(struct net_device *dev)
1383 {
1384         struct ip6_tnl *t = netdev_priv(dev);
1385
1386         gro_cells_destroy(&t->gro_cells);
1387         dst_cache_destroy(&t->dst_cache);
1388         free_percpu(dev->tstats);
1389 }
1390
1391 static void ip6gre_tunnel_setup(struct net_device *dev)
1392 {
1393         dev->netdev_ops = &ip6gre_netdev_ops;
1394         dev->needs_free_netdev = true;
1395         dev->priv_destructor = ip6gre_dev_free;
1396
1397         dev->type = ARPHRD_IP6GRE;
1398
1399         dev->flags |= IFF_NOARP;
1400         dev->addr_len = sizeof(struct in6_addr);
1401         netif_keep_dst(dev);
1402         /* This perm addr will be used as interface identifier by IPv6 */
1403         dev->addr_assign_type = NET_ADDR_RANDOM;
1404         eth_random_addr(dev->perm_addr);
1405 }
1406
1407 #define GRE6_FEATURES (NETIF_F_SG |             \
1408                        NETIF_F_FRAGLIST |       \
1409                        NETIF_F_HIGHDMA |        \
1410                        NETIF_F_HW_CSUM)
1411
1412 static void ip6gre_tnl_init_features(struct net_device *dev)
1413 {
1414         struct ip6_tnl *nt = netdev_priv(dev);
1415
1416         dev->features           |= GRE6_FEATURES;
1417         dev->hw_features        |= GRE6_FEATURES;
1418
1419         if (!(nt->parms.o_flags & TUNNEL_SEQ)) {
1420                 /* TCP offload with GRE SEQ is not supported, nor
1421                  * can we support 2 levels of outer headers requiring
1422                  * an update.
1423                  */
1424                 if (!(nt->parms.o_flags & TUNNEL_CSUM) ||
1425                     nt->encap.type == TUNNEL_ENCAP_NONE) {
1426                         dev->features    |= NETIF_F_GSO_SOFTWARE;
1427                         dev->hw_features |= NETIF_F_GSO_SOFTWARE;
1428                 }
1429
1430                 /* Can use a lockless transmit, unless we generate
1431                  * output sequences
1432                  */
1433                 dev->features |= NETIF_F_LLTX;
1434         }
1435 }
1436
1437 static int ip6gre_tunnel_init_common(struct net_device *dev)
1438 {
1439         struct ip6_tnl *tunnel;
1440         int ret;
1441         int t_hlen;
1442
1443         tunnel = netdev_priv(dev);
1444
1445         tunnel->dev = dev;
1446         tunnel->net = dev_net(dev);
1447         strcpy(tunnel->parms.name, dev->name);
1448
1449         dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1450         if (!dev->tstats)
1451                 return -ENOMEM;
1452
1453         ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1454         if (ret)
1455                 goto cleanup_alloc_pcpu_stats;
1456
1457         ret = gro_cells_init(&tunnel->gro_cells, dev);
1458         if (ret)
1459                 goto cleanup_dst_cache_init;
1460
1461         t_hlen = ip6gre_calc_hlen(tunnel);
1462         dev->mtu = ETH_DATA_LEN - t_hlen;
1463         if (dev->type == ARPHRD_ETHER)
1464                 dev->mtu -= ETH_HLEN;
1465         if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1466                 dev->mtu -= 8;
1467
1468         if (tunnel->parms.collect_md) {
1469                 dev->features |= NETIF_F_NETNS_LOCAL;
1470                 netif_keep_dst(dev);
1471         }
1472         ip6gre_tnl_init_features(dev);
1473
1474         return 0;
1475
1476 cleanup_dst_cache_init:
1477         dst_cache_destroy(&tunnel->dst_cache);
1478 cleanup_alloc_pcpu_stats:
1479         free_percpu(dev->tstats);
1480         dev->tstats = NULL;
1481         return ret;
1482 }
1483
1484 static int ip6gre_tunnel_init(struct net_device *dev)
1485 {
1486         struct ip6_tnl *tunnel;
1487         int ret;
1488
1489         ret = ip6gre_tunnel_init_common(dev);
1490         if (ret)
1491                 return ret;
1492
1493         tunnel = netdev_priv(dev);
1494
1495         if (tunnel->parms.collect_md)
1496                 return 0;
1497
1498         memcpy(dev->dev_addr, &tunnel->parms.laddr, sizeof(struct in6_addr));
1499         memcpy(dev->broadcast, &tunnel->parms.raddr, sizeof(struct in6_addr));
1500
1501         if (ipv6_addr_any(&tunnel->parms.raddr))
1502                 dev->header_ops = &ip6gre_header_ops;
1503
1504         return 0;
1505 }
1506
1507 static void ip6gre_fb_tunnel_init(struct net_device *dev)
1508 {
1509         struct ip6_tnl *tunnel = netdev_priv(dev);
1510
1511         tunnel->dev = dev;
1512         tunnel->net = dev_net(dev);
1513         strcpy(tunnel->parms.name, dev->name);
1514
1515         tunnel->hlen            = sizeof(struct ipv6hdr) + 4;
1516
1517         dev_hold(dev);
1518 }
1519
1520 static struct inet6_protocol ip6gre_protocol __read_mostly = {
1521         .handler     = gre_rcv,
1522         .err_handler = ip6gre_err,
1523         .flags       = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1524 };
1525
1526 static void ip6gre_destroy_tunnels(struct net *net, struct list_head *head)
1527 {
1528         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1529         struct net_device *dev, *aux;
1530         int prio;
1531
1532         for_each_netdev_safe(net, dev, aux)
1533                 if (dev->rtnl_link_ops == &ip6gre_link_ops ||
1534                     dev->rtnl_link_ops == &ip6gre_tap_ops ||
1535                     dev->rtnl_link_ops == &ip6erspan_tap_ops)
1536                         unregister_netdevice_queue(dev, head);
1537
1538         for (prio = 0; prio < 4; prio++) {
1539                 int h;
1540                 for (h = 0; h < IP6_GRE_HASH_SIZE; h++) {
1541                         struct ip6_tnl *t;
1542
1543                         t = rtnl_dereference(ign->tunnels[prio][h]);
1544
1545                         while (t) {
1546                                 /* If dev is in the same netns, it has already
1547                                  * been added to the list by the previous loop.
1548                                  */
1549                                 if (!net_eq(dev_net(t->dev), net))
1550                                         unregister_netdevice_queue(t->dev,
1551                                                                    head);
1552                                 t = rtnl_dereference(t->next);
1553                         }
1554                 }
1555         }
1556 }
1557
1558 static int __net_init ip6gre_init_net(struct net *net)
1559 {
1560         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1561         int err;
1562
1563         if (!net_has_fallback_tunnels(net))
1564                 return 0;
1565         ign->fb_tunnel_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6gre0",
1566                                           NET_NAME_UNKNOWN,
1567                                           ip6gre_tunnel_setup);
1568         if (!ign->fb_tunnel_dev) {
1569                 err = -ENOMEM;
1570                 goto err_alloc_dev;
1571         }
1572         dev_net_set(ign->fb_tunnel_dev, net);
1573         /* FB netdevice is special: we have one, and only one per netns.
1574          * Allowing to move it to another netns is clearly unsafe.
1575          */
1576         ign->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL;
1577
1578
1579         ip6gre_fb_tunnel_init(ign->fb_tunnel_dev);
1580         ign->fb_tunnel_dev->rtnl_link_ops = &ip6gre_link_ops;
1581
1582         err = register_netdev(ign->fb_tunnel_dev);
1583         if (err)
1584                 goto err_reg_dev;
1585
1586         rcu_assign_pointer(ign->tunnels_wc[0],
1587                            netdev_priv(ign->fb_tunnel_dev));
1588         return 0;
1589
1590 err_reg_dev:
1591         free_netdev(ign->fb_tunnel_dev);
1592 err_alloc_dev:
1593         return err;
1594 }
1595
1596 static void __net_exit ip6gre_exit_batch_net(struct list_head *net_list)
1597 {
1598         struct net *net;
1599         LIST_HEAD(list);
1600
1601         rtnl_lock();
1602         list_for_each_entry(net, net_list, exit_list)
1603                 ip6gre_destroy_tunnels(net, &list);
1604         unregister_netdevice_many(&list);
1605         rtnl_unlock();
1606 }
1607
1608 static struct pernet_operations ip6gre_net_ops = {
1609         .init = ip6gre_init_net,
1610         .exit_batch = ip6gre_exit_batch_net,
1611         .id   = &ip6gre_net_id,
1612         .size = sizeof(struct ip6gre_net),
1613 };
1614
1615 static int ip6gre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[],
1616                                   struct netlink_ext_ack *extack)
1617 {
1618         __be16 flags;
1619
1620         if (!data)
1621                 return 0;
1622
1623         flags = 0;
1624         if (data[IFLA_GRE_IFLAGS])
1625                 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1626         if (data[IFLA_GRE_OFLAGS])
1627                 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1628         if (flags & (GRE_VERSION|GRE_ROUTING))
1629                 return -EINVAL;
1630
1631         return 0;
1632 }
1633
1634 static int ip6gre_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1635                                struct netlink_ext_ack *extack)
1636 {
1637         struct in6_addr daddr;
1638
1639         if (tb[IFLA_ADDRESS]) {
1640                 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
1641                         return -EINVAL;
1642                 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
1643                         return -EADDRNOTAVAIL;
1644         }
1645
1646         if (!data)
1647                 goto out;
1648
1649         if (data[IFLA_GRE_REMOTE]) {
1650                 daddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]);
1651                 if (ipv6_addr_any(&daddr))
1652                         return -EINVAL;
1653         }
1654
1655 out:
1656         return ip6gre_tunnel_validate(tb, data, extack);
1657 }
1658
1659 static int ip6erspan_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1660                                   struct netlink_ext_ack *extack)
1661 {
1662         __be16 flags = 0;
1663         int ret, ver = 0;
1664
1665         if (!data)
1666                 return 0;
1667
1668         ret = ip6gre_tap_validate(tb, data, extack);
1669         if (ret)
1670                 return ret;
1671
1672         /* ERSPAN should only have GRE sequence and key flag */
1673         if (data[IFLA_GRE_OFLAGS])
1674                 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1675         if (data[IFLA_GRE_IFLAGS])
1676                 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1677         if (!data[IFLA_GRE_COLLECT_METADATA] &&
1678             flags != (GRE_SEQ | GRE_KEY))
1679                 return -EINVAL;
1680
1681         /* ERSPAN Session ID only has 10-bit. Since we reuse
1682          * 32-bit key field as ID, check it's range.
1683          */
1684         if (data[IFLA_GRE_IKEY] &&
1685             (ntohl(nla_get_be32(data[IFLA_GRE_IKEY])) & ~ID_MASK))
1686                 return -EINVAL;
1687
1688         if (data[IFLA_GRE_OKEY] &&
1689             (ntohl(nla_get_be32(data[IFLA_GRE_OKEY])) & ~ID_MASK))
1690                 return -EINVAL;
1691
1692         if (data[IFLA_GRE_ERSPAN_VER]) {
1693                 ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1694                 if (ver != 1 && ver != 2)
1695                         return -EINVAL;
1696         }
1697
1698         if (ver == 1) {
1699                 if (data[IFLA_GRE_ERSPAN_INDEX]) {
1700                         u32 index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1701
1702                         if (index & ~INDEX_MASK)
1703                                 return -EINVAL;
1704                 }
1705         } else if (ver == 2) {
1706                 if (data[IFLA_GRE_ERSPAN_DIR]) {
1707                         u16 dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1708
1709                         if (dir & ~(DIR_MASK >> DIR_OFFSET))
1710                                 return -EINVAL;
1711                 }
1712
1713                 if (data[IFLA_GRE_ERSPAN_HWID]) {
1714                         u16 hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1715
1716                         if (hwid & ~(HWID_MASK >> HWID_OFFSET))
1717                                 return -EINVAL;
1718                 }
1719         }
1720
1721         return 0;
1722 }
1723
1724 static void ip6erspan_set_version(struct nlattr *data[],
1725                                   struct __ip6_tnl_parm *parms)
1726 {
1727         if (!data)
1728                 return;
1729
1730         parms->erspan_ver = 1;
1731         if (data[IFLA_GRE_ERSPAN_VER])
1732                 parms->erspan_ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1733
1734         if (parms->erspan_ver == 1) {
1735                 if (data[IFLA_GRE_ERSPAN_INDEX])
1736                         parms->index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1737         } else if (parms->erspan_ver == 2) {
1738                 if (data[IFLA_GRE_ERSPAN_DIR])
1739                         parms->dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1740                 if (data[IFLA_GRE_ERSPAN_HWID])
1741                         parms->hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1742         }
1743 }
1744
1745 static void ip6gre_netlink_parms(struct nlattr *data[],
1746                                 struct __ip6_tnl_parm *parms)
1747 {
1748         memset(parms, 0, sizeof(*parms));
1749
1750         if (!data)
1751                 return;
1752
1753         if (data[IFLA_GRE_LINK])
1754                 parms->link = nla_get_u32(data[IFLA_GRE_LINK]);
1755
1756         if (data[IFLA_GRE_IFLAGS])
1757                 parms->i_flags = gre_flags_to_tnl_flags(
1758                                 nla_get_be16(data[IFLA_GRE_IFLAGS]));
1759
1760         if (data[IFLA_GRE_OFLAGS])
1761                 parms->o_flags = gre_flags_to_tnl_flags(
1762                                 nla_get_be16(data[IFLA_GRE_OFLAGS]));
1763
1764         if (data[IFLA_GRE_IKEY])
1765                 parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]);
1766
1767         if (data[IFLA_GRE_OKEY])
1768                 parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]);
1769
1770         if (data[IFLA_GRE_LOCAL])
1771                 parms->laddr = nla_get_in6_addr(data[IFLA_GRE_LOCAL]);
1772
1773         if (data[IFLA_GRE_REMOTE])
1774                 parms->raddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]);
1775
1776         if (data[IFLA_GRE_TTL])
1777                 parms->hop_limit = nla_get_u8(data[IFLA_GRE_TTL]);
1778
1779         if (data[IFLA_GRE_ENCAP_LIMIT])
1780                 parms->encap_limit = nla_get_u8(data[IFLA_GRE_ENCAP_LIMIT]);
1781
1782         if (data[IFLA_GRE_FLOWINFO])
1783                 parms->flowinfo = nla_get_be32(data[IFLA_GRE_FLOWINFO]);
1784
1785         if (data[IFLA_GRE_FLAGS])
1786                 parms->flags = nla_get_u32(data[IFLA_GRE_FLAGS]);
1787
1788         if (data[IFLA_GRE_FWMARK])
1789                 parms->fwmark = nla_get_u32(data[IFLA_GRE_FWMARK]);
1790
1791         if (data[IFLA_GRE_COLLECT_METADATA])
1792                 parms->collect_md = true;
1793 }
1794
1795 static int ip6gre_tap_init(struct net_device *dev)
1796 {
1797         int ret;
1798
1799         ret = ip6gre_tunnel_init_common(dev);
1800         if (ret)
1801                 return ret;
1802
1803         dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1804
1805         return 0;
1806 }
1807
1808 static const struct net_device_ops ip6gre_tap_netdev_ops = {
1809         .ndo_init = ip6gre_tap_init,
1810         .ndo_uninit = ip6gre_tunnel_uninit,
1811         .ndo_start_xmit = ip6gre_tunnel_xmit,
1812         .ndo_set_mac_address = eth_mac_addr,
1813         .ndo_validate_addr = eth_validate_addr,
1814         .ndo_change_mtu = ip6_tnl_change_mtu,
1815         .ndo_get_stats64 = ip_tunnel_get_stats64,
1816         .ndo_get_iflink = ip6_tnl_get_iflink,
1817 };
1818
1819 static int ip6erspan_calc_hlen(struct ip6_tnl *tunnel)
1820 {
1821         int t_hlen;
1822
1823         tunnel->tun_hlen = 8;
1824         tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen +
1825                        erspan_hdr_len(tunnel->parms.erspan_ver);
1826
1827         t_hlen = tunnel->hlen + sizeof(struct ipv6hdr);
1828         tunnel->dev->needed_headroom = LL_MAX_HEADER + t_hlen;
1829         return t_hlen;
1830 }
1831
1832 static int ip6erspan_tap_init(struct net_device *dev)
1833 {
1834         struct ip6_tnl *tunnel;
1835         int t_hlen;
1836         int ret;
1837
1838         tunnel = netdev_priv(dev);
1839
1840         tunnel->dev = dev;
1841         tunnel->net = dev_net(dev);
1842         strcpy(tunnel->parms.name, dev->name);
1843
1844         dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1845         if (!dev->tstats)
1846                 return -ENOMEM;
1847
1848         ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1849         if (ret)
1850                 goto cleanup_alloc_pcpu_stats;
1851
1852         ret = gro_cells_init(&tunnel->gro_cells, dev);
1853         if (ret)
1854                 goto cleanup_dst_cache_init;
1855
1856         t_hlen = ip6erspan_calc_hlen(tunnel);
1857         dev->mtu = ETH_DATA_LEN - t_hlen;
1858         if (dev->type == ARPHRD_ETHER)
1859                 dev->mtu -= ETH_HLEN;
1860         if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1861                 dev->mtu -= 8;
1862
1863         dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1864         ip6erspan_tnl_link_config(tunnel, 1);
1865
1866         return 0;
1867
1868 cleanup_dst_cache_init:
1869         dst_cache_destroy(&tunnel->dst_cache);
1870 cleanup_alloc_pcpu_stats:
1871         free_percpu(dev->tstats);
1872         dev->tstats = NULL;
1873         return ret;
1874 }
1875
1876 static const struct net_device_ops ip6erspan_netdev_ops = {
1877         .ndo_init =             ip6erspan_tap_init,
1878         .ndo_uninit =           ip6erspan_tunnel_uninit,
1879         .ndo_start_xmit =       ip6erspan_tunnel_xmit,
1880         .ndo_set_mac_address =  eth_mac_addr,
1881         .ndo_validate_addr =    eth_validate_addr,
1882         .ndo_change_mtu =       ip6_tnl_change_mtu,
1883         .ndo_get_stats64 =      ip_tunnel_get_stats64,
1884         .ndo_get_iflink =       ip6_tnl_get_iflink,
1885 };
1886
1887 static void ip6gre_tap_setup(struct net_device *dev)
1888 {
1889
1890         ether_setup(dev);
1891
1892         dev->max_mtu = 0;
1893         dev->netdev_ops = &ip6gre_tap_netdev_ops;
1894         dev->needs_free_netdev = true;
1895         dev->priv_destructor = ip6gre_dev_free;
1896
1897         dev->features |= NETIF_F_NETNS_LOCAL;
1898         dev->priv_flags &= ~IFF_TX_SKB_SHARING;
1899         dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1900         netif_keep_dst(dev);
1901 }
1902
1903 static bool ip6gre_netlink_encap_parms(struct nlattr *data[],
1904                                        struct ip_tunnel_encap *ipencap)
1905 {
1906         bool ret = false;
1907
1908         memset(ipencap, 0, sizeof(*ipencap));
1909
1910         if (!data)
1911                 return ret;
1912
1913         if (data[IFLA_GRE_ENCAP_TYPE]) {
1914                 ret = true;
1915                 ipencap->type = nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]);
1916         }
1917
1918         if (data[IFLA_GRE_ENCAP_FLAGS]) {
1919                 ret = true;
1920                 ipencap->flags = nla_get_u16(data[IFLA_GRE_ENCAP_FLAGS]);
1921         }
1922
1923         if (data[IFLA_GRE_ENCAP_SPORT]) {
1924                 ret = true;
1925                 ipencap->sport = nla_get_be16(data[IFLA_GRE_ENCAP_SPORT]);
1926         }
1927
1928         if (data[IFLA_GRE_ENCAP_DPORT]) {
1929                 ret = true;
1930                 ipencap->dport = nla_get_be16(data[IFLA_GRE_ENCAP_DPORT]);
1931         }
1932
1933         return ret;
1934 }
1935
1936 static int ip6gre_newlink_common(struct net *src_net, struct net_device *dev,
1937                                  struct nlattr *tb[], struct nlattr *data[],
1938                                  struct netlink_ext_ack *extack)
1939 {
1940         struct ip6_tnl *nt;
1941         struct ip_tunnel_encap ipencap;
1942         int err;
1943
1944         nt = netdev_priv(dev);
1945
1946         if (ip6gre_netlink_encap_parms(data, &ipencap)) {
1947                 int err = ip6_tnl_encap_setup(nt, &ipencap);
1948
1949                 if (err < 0)
1950                         return err;
1951         }
1952
1953         if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS])
1954                 eth_hw_addr_random(dev);
1955
1956         nt->dev = dev;
1957         nt->net = dev_net(dev);
1958
1959         err = register_netdevice(dev);
1960         if (err)
1961                 goto out;
1962
1963         if (tb[IFLA_MTU])
1964                 ip6_tnl_change_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
1965
1966         dev_hold(dev);
1967
1968 out:
1969         return err;
1970 }
1971
1972 static int ip6gre_newlink(struct net *src_net, struct net_device *dev,
1973                           struct nlattr *tb[], struct nlattr *data[],
1974                           struct netlink_ext_ack *extack)
1975 {
1976         struct ip6_tnl *nt = netdev_priv(dev);
1977         struct net *net = dev_net(dev);
1978         struct ip6gre_net *ign;
1979         int err;
1980
1981         ip6gre_netlink_parms(data, &nt->parms);
1982         ign = net_generic(net, ip6gre_net_id);
1983
1984         if (nt->parms.collect_md) {
1985                 if (rtnl_dereference(ign->collect_md_tun))
1986                         return -EEXIST;
1987         } else {
1988                 if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
1989                         return -EEXIST;
1990         }
1991
1992         err = ip6gre_newlink_common(src_net, dev, tb, data, extack);
1993         if (!err) {
1994                 ip6gre_tnl_link_config(nt, !tb[IFLA_MTU]);
1995                 ip6gre_tunnel_link_md(ign, nt);
1996                 ip6gre_tunnel_link(net_generic(net, ip6gre_net_id), nt);
1997         }
1998         return err;
1999 }
2000
2001 static struct ip6_tnl *
2002 ip6gre_changelink_common(struct net_device *dev, struct nlattr *tb[],
2003                          struct nlattr *data[], struct __ip6_tnl_parm *p_p,
2004                          struct netlink_ext_ack *extack)
2005 {
2006         struct ip6_tnl *t, *nt = netdev_priv(dev);
2007         struct net *net = nt->net;
2008         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
2009         struct ip_tunnel_encap ipencap;
2010
2011         if (dev == ign->fb_tunnel_dev)
2012                 return ERR_PTR(-EINVAL);
2013
2014         if (ip6gre_netlink_encap_parms(data, &ipencap)) {
2015                 int err = ip6_tnl_encap_setup(nt, &ipencap);
2016
2017                 if (err < 0)
2018                         return ERR_PTR(err);
2019         }
2020
2021         ip6gre_netlink_parms(data, p_p);
2022
2023         t = ip6gre_tunnel_locate(net, p_p, 0);
2024
2025         if (t) {
2026                 if (t->dev != dev)
2027                         return ERR_PTR(-EEXIST);
2028         } else {
2029                 t = nt;
2030         }
2031
2032         return t;
2033 }
2034
2035 static int ip6gre_changelink(struct net_device *dev, struct nlattr *tb[],
2036                              struct nlattr *data[],
2037                              struct netlink_ext_ack *extack)
2038 {
2039         struct ip6_tnl *t = netdev_priv(dev);
2040         struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
2041         struct __ip6_tnl_parm p;
2042
2043         t = ip6gre_changelink_common(dev, tb, data, &p, extack);
2044         if (IS_ERR(t))
2045                 return PTR_ERR(t);
2046
2047         ip6gre_tunnel_unlink_md(ign, t);
2048         ip6gre_tunnel_unlink(ign, t);
2049         ip6gre_tnl_change(t, &p, !tb[IFLA_MTU]);
2050         ip6gre_tunnel_link_md(ign, t);
2051         ip6gre_tunnel_link(ign, t);
2052         return 0;
2053 }
2054
2055 static void ip6gre_dellink(struct net_device *dev, struct list_head *head)
2056 {
2057         struct net *net = dev_net(dev);
2058         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
2059
2060         if (dev != ign->fb_tunnel_dev)
2061                 unregister_netdevice_queue(dev, head);
2062 }
2063
2064 static size_t ip6gre_get_size(const struct net_device *dev)
2065 {
2066         return
2067                 /* IFLA_GRE_LINK */
2068                 nla_total_size(4) +
2069                 /* IFLA_GRE_IFLAGS */
2070                 nla_total_size(2) +
2071                 /* IFLA_GRE_OFLAGS */
2072                 nla_total_size(2) +
2073                 /* IFLA_GRE_IKEY */
2074                 nla_total_size(4) +
2075                 /* IFLA_GRE_OKEY */
2076                 nla_total_size(4) +
2077                 /* IFLA_GRE_LOCAL */
2078                 nla_total_size(sizeof(struct in6_addr)) +
2079                 /* IFLA_GRE_REMOTE */
2080                 nla_total_size(sizeof(struct in6_addr)) +
2081                 /* IFLA_GRE_TTL */
2082                 nla_total_size(1) +
2083                 /* IFLA_GRE_ENCAP_LIMIT */
2084                 nla_total_size(1) +
2085                 /* IFLA_GRE_FLOWINFO */
2086                 nla_total_size(4) +
2087                 /* IFLA_GRE_FLAGS */
2088                 nla_total_size(4) +
2089                 /* IFLA_GRE_ENCAP_TYPE */
2090                 nla_total_size(2) +
2091                 /* IFLA_GRE_ENCAP_FLAGS */
2092                 nla_total_size(2) +
2093                 /* IFLA_GRE_ENCAP_SPORT */
2094                 nla_total_size(2) +
2095                 /* IFLA_GRE_ENCAP_DPORT */
2096                 nla_total_size(2) +
2097                 /* IFLA_GRE_COLLECT_METADATA */
2098                 nla_total_size(0) +
2099                 /* IFLA_GRE_FWMARK */
2100                 nla_total_size(4) +
2101                 /* IFLA_GRE_ERSPAN_INDEX */
2102                 nla_total_size(4) +
2103                 0;
2104 }
2105
2106 static int ip6gre_fill_info(struct sk_buff *skb, const struct net_device *dev)
2107 {
2108         struct ip6_tnl *t = netdev_priv(dev);
2109         struct __ip6_tnl_parm *p = &t->parms;
2110         __be16 o_flags = p->o_flags;
2111
2112         if (p->erspan_ver == 1 || p->erspan_ver == 2) {
2113                 if (!p->collect_md)
2114                         o_flags |= TUNNEL_KEY;
2115
2116                 if (nla_put_u8(skb, IFLA_GRE_ERSPAN_VER, p->erspan_ver))
2117                         goto nla_put_failure;
2118
2119                 if (p->erspan_ver == 1) {
2120                         if (nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, p->index))
2121                                 goto nla_put_failure;
2122                 } else {
2123                         if (nla_put_u8(skb, IFLA_GRE_ERSPAN_DIR, p->dir))
2124                                 goto nla_put_failure;
2125                         if (nla_put_u16(skb, IFLA_GRE_ERSPAN_HWID, p->hwid))
2126                                 goto nla_put_failure;
2127                 }
2128         }
2129
2130         if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) ||
2131             nla_put_be16(skb, IFLA_GRE_IFLAGS,
2132                          gre_tnl_flags_to_gre_flags(p->i_flags)) ||
2133             nla_put_be16(skb, IFLA_GRE_OFLAGS,
2134                          gre_tnl_flags_to_gre_flags(o_flags)) ||
2135             nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) ||
2136             nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) ||
2137             nla_put_in6_addr(skb, IFLA_GRE_LOCAL, &p->laddr) ||
2138             nla_put_in6_addr(skb, IFLA_GRE_REMOTE, &p->raddr) ||
2139             nla_put_u8(skb, IFLA_GRE_TTL, p->hop_limit) ||
2140             nla_put_u8(skb, IFLA_GRE_ENCAP_LIMIT, p->encap_limit) ||
2141             nla_put_be32(skb, IFLA_GRE_FLOWINFO, p->flowinfo) ||
2142             nla_put_u32(skb, IFLA_GRE_FLAGS, p->flags) ||
2143             nla_put_u32(skb, IFLA_GRE_FWMARK, p->fwmark))
2144                 goto nla_put_failure;
2145
2146         if (nla_put_u16(skb, IFLA_GRE_ENCAP_TYPE,
2147                         t->encap.type) ||
2148             nla_put_be16(skb, IFLA_GRE_ENCAP_SPORT,
2149                          t->encap.sport) ||
2150             nla_put_be16(skb, IFLA_GRE_ENCAP_DPORT,
2151                          t->encap.dport) ||
2152             nla_put_u16(skb, IFLA_GRE_ENCAP_FLAGS,
2153                         t->encap.flags))
2154                 goto nla_put_failure;
2155
2156         if (p->collect_md) {
2157                 if (nla_put_flag(skb, IFLA_GRE_COLLECT_METADATA))
2158                         goto nla_put_failure;
2159         }
2160
2161         return 0;
2162
2163 nla_put_failure:
2164         return -EMSGSIZE;
2165 }
2166
2167 static const struct nla_policy ip6gre_policy[IFLA_GRE_MAX + 1] = {
2168         [IFLA_GRE_LINK]        = { .type = NLA_U32 },
2169         [IFLA_GRE_IFLAGS]      = { .type = NLA_U16 },
2170         [IFLA_GRE_OFLAGS]      = { .type = NLA_U16 },
2171         [IFLA_GRE_IKEY]        = { .type = NLA_U32 },
2172         [IFLA_GRE_OKEY]        = { .type = NLA_U32 },
2173         [IFLA_GRE_LOCAL]       = { .len = FIELD_SIZEOF(struct ipv6hdr, saddr) },
2174         [IFLA_GRE_REMOTE]      = { .len = FIELD_SIZEOF(struct ipv6hdr, daddr) },
2175         [IFLA_GRE_TTL]         = { .type = NLA_U8 },
2176         [IFLA_GRE_ENCAP_LIMIT] = { .type = NLA_U8 },
2177         [IFLA_GRE_FLOWINFO]    = { .type = NLA_U32 },
2178         [IFLA_GRE_FLAGS]       = { .type = NLA_U32 },
2179         [IFLA_GRE_ENCAP_TYPE]   = { .type = NLA_U16 },
2180         [IFLA_GRE_ENCAP_FLAGS]  = { .type = NLA_U16 },
2181         [IFLA_GRE_ENCAP_SPORT]  = { .type = NLA_U16 },
2182         [IFLA_GRE_ENCAP_DPORT]  = { .type = NLA_U16 },
2183         [IFLA_GRE_COLLECT_METADATA] = { .type = NLA_FLAG },
2184         [IFLA_GRE_FWMARK]       = { .type = NLA_U32 },
2185         [IFLA_GRE_ERSPAN_INDEX] = { .type = NLA_U32 },
2186         [IFLA_GRE_ERSPAN_VER]   = { .type = NLA_U8 },
2187         [IFLA_GRE_ERSPAN_DIR]   = { .type = NLA_U8 },
2188         [IFLA_GRE_ERSPAN_HWID]  = { .type = NLA_U16 },
2189 };
2190
2191 static void ip6erspan_tap_setup(struct net_device *dev)
2192 {
2193         ether_setup(dev);
2194
2195         dev->max_mtu = 0;
2196         dev->netdev_ops = &ip6erspan_netdev_ops;
2197         dev->needs_free_netdev = true;
2198         dev->priv_destructor = ip6gre_dev_free;
2199
2200         dev->features |= NETIF_F_NETNS_LOCAL;
2201         dev->priv_flags &= ~IFF_TX_SKB_SHARING;
2202         dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
2203         netif_keep_dst(dev);
2204 }
2205
2206 static int ip6erspan_newlink(struct net *src_net, struct net_device *dev,
2207                              struct nlattr *tb[], struct nlattr *data[],
2208                              struct netlink_ext_ack *extack)
2209 {
2210         struct ip6_tnl *nt = netdev_priv(dev);
2211         struct net *net = dev_net(dev);
2212         struct ip6gre_net *ign;
2213         int err;
2214
2215         ip6gre_netlink_parms(data, &nt->parms);
2216         ip6erspan_set_version(data, &nt->parms);
2217         ign = net_generic(net, ip6gre_net_id);
2218
2219         if (nt->parms.collect_md) {
2220                 if (rtnl_dereference(ign->collect_md_tun_erspan))
2221                         return -EEXIST;
2222         } else {
2223                 if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
2224                         return -EEXIST;
2225         }
2226
2227         err = ip6gre_newlink_common(src_net, dev, tb, data, extack);
2228         if (!err) {
2229                 ip6erspan_tnl_link_config(nt, !tb[IFLA_MTU]);
2230                 ip6erspan_tunnel_link_md(ign, nt);
2231                 ip6gre_tunnel_link(net_generic(net, ip6gre_net_id), nt);
2232         }
2233         return err;
2234 }
2235
2236 static void ip6erspan_tnl_link_config(struct ip6_tnl *t, int set_mtu)
2237 {
2238         ip6gre_tnl_link_config_common(t);
2239         ip6gre_tnl_link_config_route(t, set_mtu, ip6erspan_calc_hlen(t));
2240 }
2241
2242 static int ip6erspan_tnl_change(struct ip6_tnl *t,
2243                                 const struct __ip6_tnl_parm *p, int set_mtu)
2244 {
2245         ip6gre_tnl_copy_tnl_parm(t, p);
2246         ip6erspan_tnl_link_config(t, set_mtu);
2247         return 0;
2248 }
2249
2250 static int ip6erspan_changelink(struct net_device *dev, struct nlattr *tb[],
2251                                 struct nlattr *data[],
2252                                 struct netlink_ext_ack *extack)
2253 {
2254         struct ip6gre_net *ign = net_generic(dev_net(dev), ip6gre_net_id);
2255         struct __ip6_tnl_parm p;
2256         struct ip6_tnl *t;
2257
2258         t = ip6gre_changelink_common(dev, tb, data, &p, extack);
2259         if (IS_ERR(t))
2260                 return PTR_ERR(t);
2261
2262         ip6erspan_set_version(data, &p);
2263         ip6gre_tunnel_unlink_md(ign, t);
2264         ip6gre_tunnel_unlink(ign, t);
2265         ip6erspan_tnl_change(t, &p, !tb[IFLA_MTU]);
2266         ip6erspan_tunnel_link_md(ign, t);
2267         ip6gre_tunnel_link(ign, t);
2268         return 0;
2269 }
2270
2271 static struct rtnl_link_ops ip6gre_link_ops __read_mostly = {
2272         .kind           = "ip6gre",
2273         .maxtype        = IFLA_GRE_MAX,
2274         .policy         = ip6gre_policy,
2275         .priv_size      = sizeof(struct ip6_tnl),
2276         .setup          = ip6gre_tunnel_setup,
2277         .validate       = ip6gre_tunnel_validate,
2278         .newlink        = ip6gre_newlink,
2279         .changelink     = ip6gre_changelink,
2280         .dellink        = ip6gre_dellink,
2281         .get_size       = ip6gre_get_size,
2282         .fill_info      = ip6gre_fill_info,
2283         .get_link_net   = ip6_tnl_get_link_net,
2284 };
2285
2286 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly = {
2287         .kind           = "ip6gretap",
2288         .maxtype        = IFLA_GRE_MAX,
2289         .policy         = ip6gre_policy,
2290         .priv_size      = sizeof(struct ip6_tnl),
2291         .setup          = ip6gre_tap_setup,
2292         .validate       = ip6gre_tap_validate,
2293         .newlink        = ip6gre_newlink,
2294         .changelink     = ip6gre_changelink,
2295         .get_size       = ip6gre_get_size,
2296         .fill_info      = ip6gre_fill_info,
2297         .get_link_net   = ip6_tnl_get_link_net,
2298 };
2299
2300 static struct rtnl_link_ops ip6erspan_tap_ops __read_mostly = {
2301         .kind           = "ip6erspan",
2302         .maxtype        = IFLA_GRE_MAX,
2303         .policy         = ip6gre_policy,
2304         .priv_size      = sizeof(struct ip6_tnl),
2305         .setup          = ip6erspan_tap_setup,
2306         .validate       = ip6erspan_tap_validate,
2307         .newlink        = ip6erspan_newlink,
2308         .changelink     = ip6erspan_changelink,
2309         .get_size       = ip6gre_get_size,
2310         .fill_info      = ip6gre_fill_info,
2311         .get_link_net   = ip6_tnl_get_link_net,
2312 };
2313
2314 /*
2315  *      And now the modules code and kernel interface.
2316  */
2317
2318 static int __init ip6gre_init(void)
2319 {
2320         int err;
2321
2322         pr_info("GRE over IPv6 tunneling driver\n");
2323
2324         err = register_pernet_device(&ip6gre_net_ops);
2325         if (err < 0)
2326                 return err;
2327
2328         err = inet6_add_protocol(&ip6gre_protocol, IPPROTO_GRE);
2329         if (err < 0) {
2330                 pr_info("%s: can't add protocol\n", __func__);
2331                 goto add_proto_failed;
2332         }
2333
2334         err = rtnl_link_register(&ip6gre_link_ops);
2335         if (err < 0)
2336                 goto rtnl_link_failed;
2337
2338         err = rtnl_link_register(&ip6gre_tap_ops);
2339         if (err < 0)
2340                 goto tap_ops_failed;
2341
2342         err = rtnl_link_register(&ip6erspan_tap_ops);
2343         if (err < 0)
2344                 goto erspan_link_failed;
2345
2346 out:
2347         return err;
2348
2349 erspan_link_failed:
2350         rtnl_link_unregister(&ip6gre_tap_ops);
2351 tap_ops_failed:
2352         rtnl_link_unregister(&ip6gre_link_ops);
2353 rtnl_link_failed:
2354         inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
2355 add_proto_failed:
2356         unregister_pernet_device(&ip6gre_net_ops);
2357         goto out;
2358 }
2359
2360 static void __exit ip6gre_fini(void)
2361 {
2362         rtnl_link_unregister(&ip6gre_tap_ops);
2363         rtnl_link_unregister(&ip6gre_link_ops);
2364         rtnl_link_unregister(&ip6erspan_tap_ops);
2365         inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
2366         unregister_pernet_device(&ip6gre_net_ops);
2367 }
2368
2369 module_init(ip6gre_init);
2370 module_exit(ip6gre_fini);
2371 MODULE_LICENSE("GPL");
2372 MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)");
2373 MODULE_DESCRIPTION("GRE over IPv6 tunneling device");
2374 MODULE_ALIAS_RTNL_LINK("ip6gre");
2375 MODULE_ALIAS_RTNL_LINK("ip6gretap");
2376 MODULE_ALIAS_RTNL_LINK("ip6erspan");
2377 MODULE_ALIAS_NETDEV("ip6gre0");