Merge branch 'misc.namei' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
[linux-2.6-microblaze.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         struct net_device *ndev;
131
132         for_each_ip_tunnel_rcu(t, ign->tunnels_r_l[h0 ^ h1]) {
133                 if (!ipv6_addr_equal(local, &t->parms.laddr) ||
134                     !ipv6_addr_equal(remote, &t->parms.raddr) ||
135                     key != t->parms.i_key ||
136                     !(t->dev->flags & IFF_UP))
137                         continue;
138
139                 if (t->dev->type != ARPHRD_IP6GRE &&
140                     t->dev->type != dev_type)
141                         continue;
142
143                 score = 0;
144                 if (t->parms.link != link)
145                         score |= 1;
146                 if (t->dev->type != dev_type)
147                         score |= 2;
148                 if (score == 0)
149                         return t;
150
151                 if (score < cand_score) {
152                         cand = t;
153                         cand_score = score;
154                 }
155         }
156
157         for_each_ip_tunnel_rcu(t, ign->tunnels_r[h0 ^ h1]) {
158                 if (!ipv6_addr_equal(remote, &t->parms.raddr) ||
159                     key != t->parms.i_key ||
160                     !(t->dev->flags & IFF_UP))
161                         continue;
162
163                 if (t->dev->type != ARPHRD_IP6GRE &&
164                     t->dev->type != dev_type)
165                         continue;
166
167                 score = 0;
168                 if (t->parms.link != link)
169                         score |= 1;
170                 if (t->dev->type != dev_type)
171                         score |= 2;
172                 if (score == 0)
173                         return t;
174
175                 if (score < cand_score) {
176                         cand = t;
177                         cand_score = score;
178                 }
179         }
180
181         for_each_ip_tunnel_rcu(t, ign->tunnels_l[h1]) {
182                 if ((!ipv6_addr_equal(local, &t->parms.laddr) &&
183                           (!ipv6_addr_equal(local, &t->parms.raddr) ||
184                                  !ipv6_addr_is_multicast(local))) ||
185                     key != t->parms.i_key ||
186                     !(t->dev->flags & IFF_UP))
187                         continue;
188
189                 if (t->dev->type != ARPHRD_IP6GRE &&
190                     t->dev->type != dev_type)
191                         continue;
192
193                 score = 0;
194                 if (t->parms.link != link)
195                         score |= 1;
196                 if (t->dev->type != dev_type)
197                         score |= 2;
198                 if (score == 0)
199                         return t;
200
201                 if (score < cand_score) {
202                         cand = t;
203                         cand_score = score;
204                 }
205         }
206
207         for_each_ip_tunnel_rcu(t, ign->tunnels_wc[h1]) {
208                 if (t->parms.i_key != key ||
209                     !(t->dev->flags & IFF_UP))
210                         continue;
211
212                 if (t->dev->type != ARPHRD_IP6GRE &&
213                     t->dev->type != dev_type)
214                         continue;
215
216                 score = 0;
217                 if (t->parms.link != link)
218                         score |= 1;
219                 if (t->dev->type != dev_type)
220                         score |= 2;
221                 if (score == 0)
222                         return t;
223
224                 if (score < cand_score) {
225                         cand = t;
226                         cand_score = score;
227                 }
228         }
229
230         if (cand)
231                 return cand;
232
233         if (gre_proto == htons(ETH_P_ERSPAN) ||
234             gre_proto == htons(ETH_P_ERSPAN2))
235                 t = rcu_dereference(ign->collect_md_tun_erspan);
236         else
237                 t = rcu_dereference(ign->collect_md_tun);
238
239         if (t && t->dev->flags & IFF_UP)
240                 return t;
241
242         ndev = READ_ONCE(ign->fb_tunnel_dev);
243         if (ndev && ndev->flags & IFF_UP)
244                 return netdev_priv(ndev);
245
246         return NULL;
247 }
248
249 static struct ip6_tnl __rcu **__ip6gre_bucket(struct ip6gre_net *ign,
250                 const struct __ip6_tnl_parm *p)
251 {
252         const struct in6_addr *remote = &p->raddr;
253         const struct in6_addr *local = &p->laddr;
254         unsigned int h = HASH_KEY(p->i_key);
255         int prio = 0;
256
257         if (!ipv6_addr_any(local))
258                 prio |= 1;
259         if (!ipv6_addr_any(remote) && !ipv6_addr_is_multicast(remote)) {
260                 prio |= 2;
261                 h ^= HASH_ADDR(remote);
262         }
263
264         return &ign->tunnels[prio][h];
265 }
266
267 static void ip6gre_tunnel_link_md(struct ip6gre_net *ign, struct ip6_tnl *t)
268 {
269         if (t->parms.collect_md)
270                 rcu_assign_pointer(ign->collect_md_tun, t);
271 }
272
273 static void ip6erspan_tunnel_link_md(struct ip6gre_net *ign, struct ip6_tnl *t)
274 {
275         if (t->parms.collect_md)
276                 rcu_assign_pointer(ign->collect_md_tun_erspan, t);
277 }
278
279 static void ip6gre_tunnel_unlink_md(struct ip6gre_net *ign, struct ip6_tnl *t)
280 {
281         if (t->parms.collect_md)
282                 rcu_assign_pointer(ign->collect_md_tun, NULL);
283 }
284
285 static void ip6erspan_tunnel_unlink_md(struct ip6gre_net *ign,
286                                        struct ip6_tnl *t)
287 {
288         if (t->parms.collect_md)
289                 rcu_assign_pointer(ign->collect_md_tun_erspan, NULL);
290 }
291
292 static inline struct ip6_tnl __rcu **ip6gre_bucket(struct ip6gre_net *ign,
293                 const struct ip6_tnl *t)
294 {
295         return __ip6gre_bucket(ign, &t->parms);
296 }
297
298 static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t)
299 {
300         struct ip6_tnl __rcu **tp = ip6gre_bucket(ign, t);
301
302         rcu_assign_pointer(t->next, rtnl_dereference(*tp));
303         rcu_assign_pointer(*tp, t);
304 }
305
306 static void ip6gre_tunnel_unlink(struct ip6gre_net *ign, struct ip6_tnl *t)
307 {
308         struct ip6_tnl __rcu **tp;
309         struct ip6_tnl *iter;
310
311         for (tp = ip6gre_bucket(ign, t);
312              (iter = rtnl_dereference(*tp)) != NULL;
313              tp = &iter->next) {
314                 if (t == iter) {
315                         rcu_assign_pointer(*tp, t->next);
316                         break;
317                 }
318         }
319 }
320
321 static struct ip6_tnl *ip6gre_tunnel_find(struct net *net,
322                                            const struct __ip6_tnl_parm *parms,
323                                            int type)
324 {
325         const struct in6_addr *remote = &parms->raddr;
326         const struct in6_addr *local = &parms->laddr;
327         __be32 key = parms->i_key;
328         int link = parms->link;
329         struct ip6_tnl *t;
330         struct ip6_tnl __rcu **tp;
331         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
332
333         for (tp = __ip6gre_bucket(ign, parms);
334              (t = rtnl_dereference(*tp)) != NULL;
335              tp = &t->next)
336                 if (ipv6_addr_equal(local, &t->parms.laddr) &&
337                     ipv6_addr_equal(remote, &t->parms.raddr) &&
338                     key == t->parms.i_key &&
339                     link == t->parms.link &&
340                     type == t->dev->type)
341                         break;
342
343         return t;
344 }
345
346 static struct ip6_tnl *ip6gre_tunnel_locate(struct net *net,
347                 const struct __ip6_tnl_parm *parms, int create)
348 {
349         struct ip6_tnl *t, *nt;
350         struct net_device *dev;
351         char name[IFNAMSIZ];
352         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
353
354         t = ip6gre_tunnel_find(net, parms, ARPHRD_IP6GRE);
355         if (t && create)
356                 return NULL;
357         if (t || !create)
358                 return t;
359
360         if (parms->name[0]) {
361                 if (!dev_valid_name(parms->name))
362                         return NULL;
363                 strlcpy(name, parms->name, IFNAMSIZ);
364         } else {
365                 strcpy(name, "ip6gre%d");
366         }
367         dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN,
368                            ip6gre_tunnel_setup);
369         if (!dev)
370                 return NULL;
371
372         dev_net_set(dev, net);
373
374         nt = netdev_priv(dev);
375         nt->parms = *parms;
376         dev->rtnl_link_ops = &ip6gre_link_ops;
377
378         nt->dev = dev;
379         nt->net = dev_net(dev);
380
381         if (register_netdevice(dev) < 0)
382                 goto failed_free;
383
384         ip6gre_tnl_link_config(nt, 1);
385
386         /* Can use a lockless transmit, unless we generate output sequences */
387         if (!(nt->parms.o_flags & TUNNEL_SEQ))
388                 dev->features |= NETIF_F_LLTX;
389
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         if (ign->fb_tunnel_dev == dev)
417                 WRITE_ONCE(ign->fb_tunnel_dev, NULL);
418         dst_cache_reset(&t->dst_cache);
419         dev_put(dev);
420 }
421
422
423 static int ip6gre_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
424                        u8 type, u8 code, int offset, __be32 info)
425 {
426         struct net *net = dev_net(skb->dev);
427         const struct ipv6hdr *ipv6h;
428         struct tnl_ptk_info tpi;
429         struct ip6_tnl *t;
430
431         if (gre_parse_header(skb, &tpi, NULL, htons(ETH_P_IPV6),
432                              offset) < 0)
433                 return -EINVAL;
434
435         ipv6h = (const struct ipv6hdr *)skb->data;
436         t = ip6gre_tunnel_lookup(skb->dev, &ipv6h->daddr, &ipv6h->saddr,
437                                  tpi.key, tpi.proto);
438         if (!t)
439                 return -ENOENT;
440
441         switch (type) {
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                 struct ipv6_tlv_tnl_enc_lim *tel;
457                 __u32 teli;
458
459                 teli = 0;
460                 if (code == ICMPV6_HDR_FIELD)
461                         teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data);
462
463                 if (teli && teli == be32_to_cpu(info) - 2) {
464                         tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli];
465                         if (tel->encap_limit == 0) {
466                                 net_dbg_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n",
467                                                     t->parms.name);
468                         }
469                 } else {
470                         net_dbg_ratelimited("%s: Recipient unable to parse tunneled packet!\n",
471                                             t->parms.name);
472                 }
473                 return 0;
474         }
475         case ICMPV6_PKT_TOOBIG:
476                 ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL));
477                 return 0;
478         case NDISC_REDIRECT:
479                 ip6_redirect(skb, net, skb->dev->ifindex, 0,
480                              sock_net_uid(net, NULL));
481                 return 0;
482         }
483
484         if (time_before(jiffies, t->err_time + IP6TUNNEL_ERR_TIMEO))
485                 t->err_count++;
486         else
487                 t->err_count = 1;
488         t->err_time = jiffies;
489
490         return 0;
491 }
492
493 static int ip6gre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi)
494 {
495         const struct ipv6hdr *ipv6h;
496         struct ip6_tnl *tunnel;
497
498         ipv6h = ipv6_hdr(skb);
499         tunnel = ip6gre_tunnel_lookup(skb->dev,
500                                       &ipv6h->saddr, &ipv6h->daddr, tpi->key,
501                                       tpi->proto);
502         if (tunnel) {
503                 if (tunnel->parms.collect_md) {
504                         struct metadata_dst *tun_dst;
505                         __be64 tun_id;
506                         __be16 flags;
507
508                         flags = tpi->flags;
509                         tun_id = key32_to_tunnel_id(tpi->key);
510
511                         tun_dst = ipv6_tun_rx_dst(skb, flags, tun_id, 0);
512                         if (!tun_dst)
513                                 return PACKET_REJECT;
514
515                         ip6_tnl_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
516                 } else {
517                         ip6_tnl_rcv(tunnel, skb, tpi, NULL, log_ecn_error);
518                 }
519
520                 return PACKET_RCVD;
521         }
522
523         return PACKET_REJECT;
524 }
525
526 static int ip6erspan_rcv(struct sk_buff *skb,
527                          struct tnl_ptk_info *tpi,
528                          int gre_hdr_len)
529 {
530         struct erspan_base_hdr *ershdr;
531         const struct ipv6hdr *ipv6h;
532         struct erspan_md2 *md2;
533         struct ip6_tnl *tunnel;
534         u8 ver;
535
536         ipv6h = ipv6_hdr(skb);
537         ershdr = (struct erspan_base_hdr *)skb->data;
538         ver = ershdr->ver;
539
540         tunnel = ip6gre_tunnel_lookup(skb->dev,
541                                       &ipv6h->saddr, &ipv6h->daddr, tpi->key,
542                                       tpi->proto);
543         if (tunnel) {
544                 int len = erspan_hdr_len(ver);
545
546                 if (unlikely(!pskb_may_pull(skb, len)))
547                         return PACKET_REJECT;
548
549                 if (__iptunnel_pull_header(skb, len,
550                                            htons(ETH_P_TEB),
551                                            false, false) < 0)
552                         return PACKET_REJECT;
553
554                 if (tunnel->parms.collect_md) {
555                         struct erspan_metadata *pkt_md, *md;
556                         struct metadata_dst *tun_dst;
557                         struct ip_tunnel_info *info;
558                         unsigned char *gh;
559                         __be64 tun_id;
560                         __be16 flags;
561
562                         tpi->flags |= TUNNEL_KEY;
563                         flags = tpi->flags;
564                         tun_id = key32_to_tunnel_id(tpi->key);
565
566                         tun_dst = ipv6_tun_rx_dst(skb, flags, tun_id,
567                                                   sizeof(*md));
568                         if (!tun_dst)
569                                 return PACKET_REJECT;
570
571                         /* skb can be uncloned in __iptunnel_pull_header, so
572                          * old pkt_md is no longer valid and we need to reset
573                          * it
574                          */
575                         gh = skb_network_header(skb) +
576                              skb_network_header_len(skb);
577                         pkt_md = (struct erspan_metadata *)(gh + gre_hdr_len +
578                                                             sizeof(*ershdr));
579                         info = &tun_dst->u.tun_info;
580                         md = ip_tunnel_info_opts(info);
581                         md->version = ver;
582                         md2 = &md->u.md2;
583                         memcpy(md2, pkt_md, ver == 1 ? ERSPAN_V1_MDSIZE :
584                                                        ERSPAN_V2_MDSIZE);
585                         info->key.tun_flags |= TUNNEL_ERSPAN_OPT;
586                         info->options_len = sizeof(*md);
587
588                         ip6_tnl_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
589
590                 } else {
591                         ip6_tnl_rcv(tunnel, skb, tpi, NULL, log_ecn_error);
592                 }
593
594                 return PACKET_RCVD;
595         }
596
597         return PACKET_REJECT;
598 }
599
600 static int gre_rcv(struct sk_buff *skb)
601 {
602         struct tnl_ptk_info tpi;
603         bool csum_err = false;
604         int hdr_len;
605
606         hdr_len = gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IPV6), 0);
607         if (hdr_len < 0)
608                 goto drop;
609
610         if (iptunnel_pull_header(skb, hdr_len, tpi.proto, false))
611                 goto drop;
612
613         if (unlikely(tpi.proto == htons(ETH_P_ERSPAN) ||
614                      tpi.proto == htons(ETH_P_ERSPAN2))) {
615                 if (ip6erspan_rcv(skb, &tpi, hdr_len) == PACKET_RCVD)
616                         return 0;
617                 goto out;
618         }
619
620         if (ip6gre_rcv(skb, &tpi) == PACKET_RCVD)
621                 return 0;
622
623 out:
624         icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
625 drop:
626         kfree_skb(skb);
627         return 0;
628 }
629
630 static int gre_handle_offloads(struct sk_buff *skb, bool csum)
631 {
632         return iptunnel_handle_offloads(skb,
633                                         csum ? SKB_GSO_GRE_CSUM : SKB_GSO_GRE);
634 }
635
636 static void prepare_ip6gre_xmit_ipv4(struct sk_buff *skb,
637                                      struct net_device *dev,
638                                      struct flowi6 *fl6, __u8 *dsfield,
639                                      int *encap_limit)
640 {
641         const struct iphdr *iph = ip_hdr(skb);
642         struct ip6_tnl *t = netdev_priv(dev);
643
644         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
645                 *encap_limit = t->parms.encap_limit;
646
647         memcpy(fl6, &t->fl.u.ip6, sizeof(*fl6));
648
649         if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
650                 *dsfield = ipv4_get_dsfield(iph);
651         else
652                 *dsfield = ip6_tclass(t->parms.flowinfo);
653
654         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
655                 fl6->flowi6_mark = skb->mark;
656         else
657                 fl6->flowi6_mark = t->parms.fwmark;
658
659         fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
660 }
661
662 static int prepare_ip6gre_xmit_ipv6(struct sk_buff *skb,
663                                     struct net_device *dev,
664                                     struct flowi6 *fl6, __u8 *dsfield,
665                                     int *encap_limit)
666 {
667         struct ipv6hdr *ipv6h;
668         struct ip6_tnl *t = netdev_priv(dev);
669         __u16 offset;
670
671         offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb));
672         /* ip6_tnl_parse_tlv_enc_lim() might have reallocated skb->head */
673         ipv6h = ipv6_hdr(skb);
674
675         if (offset > 0) {
676                 struct ipv6_tlv_tnl_enc_lim *tel;
677
678                 tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset];
679                 if (tel->encap_limit == 0) {
680                         icmpv6_ndo_send(skb, ICMPV6_PARAMPROB,
681                                         ICMPV6_HDR_FIELD, offset + 2);
682                         return -1;
683                 }
684                 *encap_limit = tel->encap_limit - 1;
685         } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) {
686                 *encap_limit = t->parms.encap_limit;
687         }
688
689         memcpy(fl6, &t->fl.u.ip6, sizeof(*fl6));
690
691         if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
692                 *dsfield = ipv6_get_dsfield(ipv6h);
693         else
694                 *dsfield = ip6_tclass(t->parms.flowinfo);
695
696         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)
697                 fl6->flowlabel |= ip6_flowlabel(ipv6h);
698
699         if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
700                 fl6->flowi6_mark = skb->mark;
701         else
702                 fl6->flowi6_mark = t->parms.fwmark;
703
704         fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
705
706         return 0;
707 }
708
709 static struct ip_tunnel_info *skb_tunnel_info_txcheck(struct sk_buff *skb)
710 {
711         struct ip_tunnel_info *tun_info;
712
713         tun_info = skb_tunnel_info(skb);
714         if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX)))
715                 return ERR_PTR(-EINVAL);
716
717         return tun_info;
718 }
719
720 static netdev_tx_t __gre6_xmit(struct sk_buff *skb,
721                                struct net_device *dev, __u8 dsfield,
722                                struct flowi6 *fl6, int encap_limit,
723                                __u32 *pmtu, __be16 proto)
724 {
725         struct ip6_tnl *tunnel = netdev_priv(dev);
726         __be16 protocol;
727
728         if (dev->type == ARPHRD_ETHER)
729                 IPCB(skb)->flags = 0;
730
731         if (dev->header_ops && dev->type == ARPHRD_IP6GRE)
732                 fl6->daddr = ((struct ipv6hdr *)skb->data)->daddr;
733         else
734                 fl6->daddr = tunnel->parms.raddr;
735
736         if (skb_cow_head(skb, dev->needed_headroom ?: tunnel->hlen))
737                 return -ENOMEM;
738
739         /* Push GRE header. */
740         protocol = (dev->type == ARPHRD_ETHER) ? htons(ETH_P_TEB) : proto;
741
742         if (tunnel->parms.collect_md) {
743                 struct ip_tunnel_info *tun_info;
744                 const struct ip_tunnel_key *key;
745                 __be16 flags;
746
747                 tun_info = skb_tunnel_info_txcheck(skb);
748                 if (IS_ERR(tun_info) ||
749                     unlikely(ip_tunnel_info_af(tun_info) != AF_INET6))
750                         return -EINVAL;
751
752                 key = &tun_info->key;
753                 memset(fl6, 0, sizeof(*fl6));
754                 fl6->flowi6_proto = IPPROTO_GRE;
755                 fl6->daddr = key->u.ipv6.dst;
756                 fl6->flowlabel = key->label;
757                 fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
758
759                 dsfield = key->tos;
760                 flags = key->tun_flags &
761                         (TUNNEL_CSUM | TUNNEL_KEY | TUNNEL_SEQ);
762                 tunnel->tun_hlen = gre_calc_hlen(flags);
763
764                 gre_build_header(skb, tunnel->tun_hlen,
765                                  flags, protocol,
766                                  tunnel_id_to_key32(tun_info->key.tun_id),
767                                  (flags & TUNNEL_SEQ) ? htonl(tunnel->o_seqno++)
768                                                       : 0);
769
770         } else {
771                 if (tunnel->parms.o_flags & TUNNEL_SEQ)
772                         tunnel->o_seqno++;
773
774                 gre_build_header(skb, tunnel->tun_hlen, tunnel->parms.o_flags,
775                                  protocol, tunnel->parms.o_key,
776                                  htonl(tunnel->o_seqno));
777         }
778
779         return ip6_tnl_xmit(skb, dev, dsfield, fl6, encap_limit, pmtu,
780                             NEXTHDR_GRE);
781 }
782
783 static inline int ip6gre_xmit_ipv4(struct sk_buff *skb, struct net_device *dev)
784 {
785         struct ip6_tnl *t = netdev_priv(dev);
786         int encap_limit = -1;
787         struct flowi6 fl6;
788         __u8 dsfield = 0;
789         __u32 mtu;
790         int err;
791
792         memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
793
794         if (!t->parms.collect_md)
795                 prepare_ip6gre_xmit_ipv4(skb, dev, &fl6,
796                                          &dsfield, &encap_limit);
797
798         err = gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM));
799         if (err)
800                 return -1;
801
802         err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
803                           skb->protocol);
804         if (err != 0) {
805                 /* XXX: send ICMP error even if DF is not set. */
806                 if (err == -EMSGSIZE)
807                         icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
808                                       htonl(mtu));
809                 return -1;
810         }
811
812         return 0;
813 }
814
815 static inline int ip6gre_xmit_ipv6(struct sk_buff *skb, struct net_device *dev)
816 {
817         struct ip6_tnl *t = netdev_priv(dev);
818         struct ipv6hdr *ipv6h = ipv6_hdr(skb);
819         int encap_limit = -1;
820         struct flowi6 fl6;
821         __u8 dsfield = 0;
822         __u32 mtu;
823         int err;
824
825         if (ipv6_addr_equal(&t->parms.raddr, &ipv6h->saddr))
826                 return -1;
827
828         if (!t->parms.collect_md &&
829             prepare_ip6gre_xmit_ipv6(skb, dev, &fl6, &dsfield, &encap_limit))
830                 return -1;
831
832         if (gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM)))
833                 return -1;
834
835         err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit,
836                           &mtu, skb->protocol);
837         if (err != 0) {
838                 if (err == -EMSGSIZE)
839                         icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
840                 return -1;
841         }
842
843         return 0;
844 }
845
846 /**
847  * ip6gre_tnl_addr_conflict - compare packet addresses to tunnel's own
848  *   @t: the outgoing tunnel device
849  *   @hdr: IPv6 header from the incoming packet
850  *
851  * Description:
852  *   Avoid trivial tunneling loop by checking that tunnel exit-point
853  *   doesn't match source of incoming packet.
854  *
855  * Return:
856  *   1 if conflict,
857  *   0 else
858  **/
859
860 static inline bool ip6gre_tnl_addr_conflict(const struct ip6_tnl *t,
861         const struct ipv6hdr *hdr)
862 {
863         return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
864 }
865
866 static int ip6gre_xmit_other(struct sk_buff *skb, struct net_device *dev)
867 {
868         struct ip6_tnl *t = netdev_priv(dev);
869         int encap_limit = -1;
870         struct flowi6 fl6;
871         __u32 mtu;
872         int err;
873
874         if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
875                 encap_limit = t->parms.encap_limit;
876
877         if (!t->parms.collect_md)
878                 memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
879
880         err = gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM));
881         if (err)
882                 return err;
883
884         err = __gre6_xmit(skb, dev, 0, &fl6, encap_limit, &mtu, skb->protocol);
885
886         return err;
887 }
888
889 static netdev_tx_t ip6gre_tunnel_xmit(struct sk_buff *skb,
890         struct net_device *dev)
891 {
892         struct ip6_tnl *t = netdev_priv(dev);
893         struct net_device_stats *stats = &t->dev->stats;
894         int ret;
895
896         if (!pskb_inet_may_pull(skb))
897                 goto tx_err;
898
899         if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr))
900                 goto tx_err;
901
902         switch (skb->protocol) {
903         case htons(ETH_P_IP):
904                 ret = ip6gre_xmit_ipv4(skb, dev);
905                 break;
906         case htons(ETH_P_IPV6):
907                 ret = ip6gre_xmit_ipv6(skb, dev);
908                 break;
909         default:
910                 ret = ip6gre_xmit_other(skb, dev);
911                 break;
912         }
913
914         if (ret < 0)
915                 goto tx_err;
916
917         return NETDEV_TX_OK;
918
919 tx_err:
920         if (!t->parms.collect_md || !IS_ERR(skb_tunnel_info_txcheck(skb)))
921                 stats->tx_errors++;
922         stats->tx_dropped++;
923         kfree_skb(skb);
924         return NETDEV_TX_OK;
925 }
926
927 static netdev_tx_t ip6erspan_tunnel_xmit(struct sk_buff *skb,
928                                          struct net_device *dev)
929 {
930         struct ip_tunnel_info *tun_info = NULL;
931         struct ip6_tnl *t = netdev_priv(dev);
932         struct dst_entry *dst = skb_dst(skb);
933         struct net_device_stats *stats;
934         bool truncate = false;
935         int encap_limit = -1;
936         __u8 dsfield = false;
937         struct flowi6 fl6;
938         int err = -EINVAL;
939         __be16 proto;
940         __u32 mtu;
941         int nhoff;
942         int thoff;
943
944         if (!pskb_inet_may_pull(skb))
945                 goto tx_err;
946
947         if (!ip6_tnl_xmit_ctl(t, &t->parms.laddr, &t->parms.raddr))
948                 goto tx_err;
949
950         if (gre_handle_offloads(skb, false))
951                 goto tx_err;
952
953         if (skb->len > dev->mtu + dev->hard_header_len) {
954                 pskb_trim(skb, dev->mtu + dev->hard_header_len);
955                 truncate = true;
956         }
957
958         nhoff = skb_network_header(skb) - skb_mac_header(skb);
959         if (skb->protocol == htons(ETH_P_IP) &&
960             (ntohs(ip_hdr(skb)->tot_len) > skb->len - nhoff))
961                 truncate = true;
962
963         thoff = skb_transport_header(skb) - skb_mac_header(skb);
964         if (skb->protocol == htons(ETH_P_IPV6) &&
965             (ntohs(ipv6_hdr(skb)->payload_len) > skb->len - thoff))
966                 truncate = true;
967
968         if (skb_cow_head(skb, dev->needed_headroom ?: t->hlen))
969                 goto tx_err;
970
971         t->parms.o_flags &= ~TUNNEL_KEY;
972         IPCB(skb)->flags = 0;
973
974         /* For collect_md mode, derive fl6 from the tunnel key,
975          * for native mode, call prepare_ip6gre_xmit_{ipv4,ipv6}.
976          */
977         if (t->parms.collect_md) {
978                 const struct ip_tunnel_key *key;
979                 struct erspan_metadata *md;
980                 __be32 tun_id;
981
982                 tun_info = skb_tunnel_info_txcheck(skb);
983                 if (IS_ERR(tun_info) ||
984                     unlikely(ip_tunnel_info_af(tun_info) != AF_INET6))
985                         goto tx_err;
986
987                 key = &tun_info->key;
988                 memset(&fl6, 0, sizeof(fl6));
989                 fl6.flowi6_proto = IPPROTO_GRE;
990                 fl6.daddr = key->u.ipv6.dst;
991                 fl6.flowlabel = key->label;
992                 fl6.flowi6_uid = sock_net_uid(dev_net(dev), NULL);
993
994                 dsfield = key->tos;
995                 if (!(tun_info->key.tun_flags & TUNNEL_ERSPAN_OPT))
996                         goto tx_err;
997                 if (tun_info->options_len < sizeof(*md))
998                         goto tx_err;
999                 md = ip_tunnel_info_opts(tun_info);
1000
1001                 tun_id = tunnel_id_to_key32(key->tun_id);
1002                 if (md->version == 1) {
1003                         erspan_build_header(skb,
1004                                             ntohl(tun_id),
1005                                             ntohl(md->u.index), truncate,
1006                                             false);
1007                 } else if (md->version == 2) {
1008                         erspan_build_header_v2(skb,
1009                                                ntohl(tun_id),
1010                                                md->u.md2.dir,
1011                                                get_hwid(&md->u.md2),
1012                                                truncate, false);
1013                 } else {
1014                         goto tx_err;
1015                 }
1016         } else {
1017                 switch (skb->protocol) {
1018                 case htons(ETH_P_IP):
1019                         memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
1020                         prepare_ip6gre_xmit_ipv4(skb, dev, &fl6,
1021                                                  &dsfield, &encap_limit);
1022                         break;
1023                 case htons(ETH_P_IPV6):
1024                         if (ipv6_addr_equal(&t->parms.raddr, &ipv6_hdr(skb)->saddr))
1025                                 goto tx_err;
1026                         if (prepare_ip6gre_xmit_ipv6(skb, dev, &fl6,
1027                                                      &dsfield, &encap_limit))
1028                                 goto tx_err;
1029                         break;
1030                 default:
1031                         memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
1032                         break;
1033                 }
1034
1035                 if (t->parms.erspan_ver == 1)
1036                         erspan_build_header(skb, ntohl(t->parms.o_key),
1037                                             t->parms.index,
1038                                             truncate, false);
1039                 else if (t->parms.erspan_ver == 2)
1040                         erspan_build_header_v2(skb, ntohl(t->parms.o_key),
1041                                                t->parms.dir,
1042                                                t->parms.hwid,
1043                                                truncate, false);
1044                 else
1045                         goto tx_err;
1046
1047                 fl6.daddr = t->parms.raddr;
1048         }
1049
1050         /* Push GRE header. */
1051         proto = (t->parms.erspan_ver == 1) ? htons(ETH_P_ERSPAN)
1052                                            : htons(ETH_P_ERSPAN2);
1053         gre_build_header(skb, 8, TUNNEL_SEQ, proto, 0, htonl(t->o_seqno++));
1054
1055         /* TooBig packet may have updated dst->dev's mtu */
1056         if (!t->parms.collect_md && dst && dst_mtu(dst) > dst->dev->mtu)
1057                 dst->ops->update_pmtu(dst, NULL, skb, dst->dev->mtu, false);
1058
1059         err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
1060                            NEXTHDR_GRE);
1061         if (err != 0) {
1062                 /* XXX: send ICMP error even if DF is not set. */
1063                 if (err == -EMSGSIZE) {
1064                         if (skb->protocol == htons(ETH_P_IP))
1065                                 icmp_ndo_send(skb, ICMP_DEST_UNREACH,
1066                                               ICMP_FRAG_NEEDED, htonl(mtu));
1067                         else
1068                                 icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
1069                 }
1070
1071                 goto tx_err;
1072         }
1073         return NETDEV_TX_OK;
1074
1075 tx_err:
1076         stats = &t->dev->stats;
1077         if (!IS_ERR(tun_info))
1078                 stats->tx_errors++;
1079         stats->tx_dropped++;
1080         kfree_skb(skb);
1081         return NETDEV_TX_OK;
1082 }
1083
1084 static void ip6gre_tnl_link_config_common(struct ip6_tnl *t)
1085 {
1086         struct net_device *dev = t->dev;
1087         struct __ip6_tnl_parm *p = &t->parms;
1088         struct flowi6 *fl6 = &t->fl.u.ip6;
1089
1090         if (dev->type != ARPHRD_ETHER) {
1091                 memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr));
1092                 memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
1093         }
1094
1095         /* Set up flowi template */
1096         fl6->saddr = p->laddr;
1097         fl6->daddr = p->raddr;
1098         fl6->flowi6_oif = p->link;
1099         fl6->flowlabel = 0;
1100         fl6->flowi6_proto = IPPROTO_GRE;
1101
1102         if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS))
1103                 fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo;
1104         if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL))
1105                 fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo;
1106
1107         p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET);
1108         p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
1109
1110         if (p->flags&IP6_TNL_F_CAP_XMIT &&
1111                         p->flags&IP6_TNL_F_CAP_RCV && dev->type != ARPHRD_ETHER)
1112                 dev->flags |= IFF_POINTOPOINT;
1113         else
1114                 dev->flags &= ~IFF_POINTOPOINT;
1115 }
1116
1117 static void ip6gre_tnl_link_config_route(struct ip6_tnl *t, int set_mtu,
1118                                          int t_hlen)
1119 {
1120         const struct __ip6_tnl_parm *p = &t->parms;
1121         struct net_device *dev = t->dev;
1122
1123         if (p->flags & IP6_TNL_F_CAP_XMIT) {
1124                 int strict = (ipv6_addr_type(&p->raddr) &
1125                               (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL));
1126
1127                 struct rt6_info *rt = rt6_lookup(t->net,
1128                                                  &p->raddr, &p->laddr,
1129                                                  p->link, NULL, strict);
1130
1131                 if (!rt)
1132                         return;
1133
1134                 if (rt->dst.dev) {
1135                         unsigned short dst_len = rt->dst.dev->hard_header_len +
1136                                                  t_hlen;
1137
1138                         if (t->dev->header_ops)
1139                                 dev->hard_header_len = dst_len;
1140                         else
1141                                 dev->needed_headroom = dst_len;
1142
1143                         if (set_mtu) {
1144                                 dev->mtu = rt->dst.dev->mtu - t_hlen;
1145                                 if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1146                                         dev->mtu -= 8;
1147                                 if (dev->type == ARPHRD_ETHER)
1148                                         dev->mtu -= ETH_HLEN;
1149
1150                                 if (dev->mtu < IPV6_MIN_MTU)
1151                                         dev->mtu = IPV6_MIN_MTU;
1152                         }
1153                 }
1154                 ip6_rt_put(rt);
1155         }
1156 }
1157
1158 static int ip6gre_calc_hlen(struct ip6_tnl *tunnel)
1159 {
1160         int t_hlen;
1161
1162         tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags);
1163         tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen;
1164
1165         t_hlen = tunnel->hlen + sizeof(struct ipv6hdr);
1166
1167         if (tunnel->dev->header_ops)
1168                 tunnel->dev->hard_header_len = LL_MAX_HEADER + t_hlen;
1169         else
1170                 tunnel->dev->needed_headroom = LL_MAX_HEADER + t_hlen;
1171
1172         return t_hlen;
1173 }
1174
1175 static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu)
1176 {
1177         ip6gre_tnl_link_config_common(t);
1178         ip6gre_tnl_link_config_route(t, set_mtu, ip6gre_calc_hlen(t));
1179 }
1180
1181 static void ip6gre_tnl_copy_tnl_parm(struct ip6_tnl *t,
1182                                      const struct __ip6_tnl_parm *p)
1183 {
1184         t->parms.laddr = p->laddr;
1185         t->parms.raddr = p->raddr;
1186         t->parms.flags = p->flags;
1187         t->parms.hop_limit = p->hop_limit;
1188         t->parms.encap_limit = p->encap_limit;
1189         t->parms.flowinfo = p->flowinfo;
1190         t->parms.link = p->link;
1191         t->parms.proto = p->proto;
1192         t->parms.i_key = p->i_key;
1193         t->parms.o_key = p->o_key;
1194         t->parms.i_flags = p->i_flags;
1195         t->parms.o_flags = p->o_flags;
1196         t->parms.fwmark = p->fwmark;
1197         t->parms.erspan_ver = p->erspan_ver;
1198         t->parms.index = p->index;
1199         t->parms.dir = p->dir;
1200         t->parms.hwid = p->hwid;
1201         dst_cache_reset(&t->dst_cache);
1202 }
1203
1204 static int ip6gre_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p,
1205                              int set_mtu)
1206 {
1207         ip6gre_tnl_copy_tnl_parm(t, p);
1208         ip6gre_tnl_link_config(t, set_mtu);
1209         return 0;
1210 }
1211
1212 static void ip6gre_tnl_parm_from_user(struct __ip6_tnl_parm *p,
1213         const struct ip6_tnl_parm2 *u)
1214 {
1215         p->laddr = u->laddr;
1216         p->raddr = u->raddr;
1217         p->flags = u->flags;
1218         p->hop_limit = u->hop_limit;
1219         p->encap_limit = u->encap_limit;
1220         p->flowinfo = u->flowinfo;
1221         p->link = u->link;
1222         p->i_key = u->i_key;
1223         p->o_key = u->o_key;
1224         p->i_flags = gre_flags_to_tnl_flags(u->i_flags);
1225         p->o_flags = gre_flags_to_tnl_flags(u->o_flags);
1226         memcpy(p->name, u->name, sizeof(u->name));
1227 }
1228
1229 static void ip6gre_tnl_parm_to_user(struct ip6_tnl_parm2 *u,
1230         const struct __ip6_tnl_parm *p)
1231 {
1232         u->proto = IPPROTO_GRE;
1233         u->laddr = p->laddr;
1234         u->raddr = p->raddr;
1235         u->flags = p->flags;
1236         u->hop_limit = p->hop_limit;
1237         u->encap_limit = p->encap_limit;
1238         u->flowinfo = p->flowinfo;
1239         u->link = p->link;
1240         u->i_key = p->i_key;
1241         u->o_key = p->o_key;
1242         u->i_flags = gre_tnl_flags_to_gre_flags(p->i_flags);
1243         u->o_flags = gre_tnl_flags_to_gre_flags(p->o_flags);
1244         memcpy(u->name, p->name, sizeof(u->name));
1245 }
1246
1247 static int ip6gre_tunnel_siocdevprivate(struct net_device *dev,
1248                                         struct ifreq *ifr, void __user *data,
1249                                         int cmd)
1250 {
1251         int err = 0;
1252         struct ip6_tnl_parm2 p;
1253         struct __ip6_tnl_parm p1;
1254         struct ip6_tnl *t = netdev_priv(dev);
1255         struct net *net = t->net;
1256         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1257
1258         memset(&p1, 0, sizeof(p1));
1259
1260         switch (cmd) {
1261         case SIOCGETTUNNEL:
1262                 if (dev == ign->fb_tunnel_dev) {
1263                         if (copy_from_user(&p, data, sizeof(p))) {
1264                                 err = -EFAULT;
1265                                 break;
1266                         }
1267                         ip6gre_tnl_parm_from_user(&p1, &p);
1268                         t = ip6gre_tunnel_locate(net, &p1, 0);
1269                         if (!t)
1270                                 t = netdev_priv(dev);
1271                 }
1272                 memset(&p, 0, sizeof(p));
1273                 ip6gre_tnl_parm_to_user(&p, &t->parms);
1274                 if (copy_to_user(data, &p, sizeof(p)))
1275                         err = -EFAULT;
1276                 break;
1277
1278         case SIOCADDTUNNEL:
1279         case SIOCCHGTUNNEL:
1280                 err = -EPERM;
1281                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1282                         goto done;
1283
1284                 err = -EFAULT;
1285                 if (copy_from_user(&p, data, sizeof(p)))
1286                         goto done;
1287
1288                 err = -EINVAL;
1289                 if ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING))
1290                         goto done;
1291
1292                 if (!(p.i_flags&GRE_KEY))
1293                         p.i_key = 0;
1294                 if (!(p.o_flags&GRE_KEY))
1295                         p.o_key = 0;
1296
1297                 ip6gre_tnl_parm_from_user(&p1, &p);
1298                 t = ip6gre_tunnel_locate(net, &p1, cmd == SIOCADDTUNNEL);
1299
1300                 if (dev != ign->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
1301                         if (t) {
1302                                 if (t->dev != dev) {
1303                                         err = -EEXIST;
1304                                         break;
1305                                 }
1306                         } else {
1307                                 t = netdev_priv(dev);
1308
1309                                 ip6gre_tunnel_unlink(ign, t);
1310                                 synchronize_net();
1311                                 ip6gre_tnl_change(t, &p1, 1);
1312                                 ip6gre_tunnel_link(ign, t);
1313                                 netdev_state_change(dev);
1314                         }
1315                 }
1316
1317                 if (t) {
1318                         err = 0;
1319
1320                         memset(&p, 0, sizeof(p));
1321                         ip6gre_tnl_parm_to_user(&p, &t->parms);
1322                         if (copy_to_user(data, &p, sizeof(p)))
1323                                 err = -EFAULT;
1324                 } else
1325                         err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
1326                 break;
1327
1328         case SIOCDELTUNNEL:
1329                 err = -EPERM;
1330                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1331                         goto done;
1332
1333                 if (dev == ign->fb_tunnel_dev) {
1334                         err = -EFAULT;
1335                         if (copy_from_user(&p, data, sizeof(p)))
1336                                 goto done;
1337                         err = -ENOENT;
1338                         ip6gre_tnl_parm_from_user(&p1, &p);
1339                         t = ip6gre_tunnel_locate(net, &p1, 0);
1340                         if (!t)
1341                                 goto done;
1342                         err = -EPERM;
1343                         if (t == netdev_priv(ign->fb_tunnel_dev))
1344                                 goto done;
1345                         dev = t->dev;
1346                 }
1347                 unregister_netdevice(dev);
1348                 err = 0;
1349                 break;
1350
1351         default:
1352                 err = -EINVAL;
1353         }
1354
1355 done:
1356         return err;
1357 }
1358
1359 static int ip6gre_header(struct sk_buff *skb, struct net_device *dev,
1360                          unsigned short type, const void *daddr,
1361                          const void *saddr, unsigned int len)
1362 {
1363         struct ip6_tnl *t = netdev_priv(dev);
1364         struct ipv6hdr *ipv6h;
1365         __be16 *p;
1366
1367         ipv6h = skb_push(skb, t->hlen + sizeof(*ipv6h));
1368         ip6_flow_hdr(ipv6h, 0, ip6_make_flowlabel(dev_net(dev), skb,
1369                                                   t->fl.u.ip6.flowlabel,
1370                                                   true, &t->fl.u.ip6));
1371         ipv6h->hop_limit = t->parms.hop_limit;
1372         ipv6h->nexthdr = NEXTHDR_GRE;
1373         ipv6h->saddr = t->parms.laddr;
1374         ipv6h->daddr = t->parms.raddr;
1375
1376         p = (__be16 *)(ipv6h + 1);
1377         p[0] = t->parms.o_flags;
1378         p[1] = htons(type);
1379
1380         /*
1381          *      Set the source hardware address.
1382          */
1383
1384         if (saddr)
1385                 memcpy(&ipv6h->saddr, saddr, sizeof(struct in6_addr));
1386         if (daddr)
1387                 memcpy(&ipv6h->daddr, daddr, sizeof(struct in6_addr));
1388         if (!ipv6_addr_any(&ipv6h->daddr))
1389                 return t->hlen;
1390
1391         return -t->hlen;
1392 }
1393
1394 static const struct header_ops ip6gre_header_ops = {
1395         .create = ip6gre_header,
1396 };
1397
1398 static const struct net_device_ops ip6gre_netdev_ops = {
1399         .ndo_init               = ip6gre_tunnel_init,
1400         .ndo_uninit             = ip6gre_tunnel_uninit,
1401         .ndo_start_xmit         = ip6gre_tunnel_xmit,
1402         .ndo_siocdevprivate     = ip6gre_tunnel_siocdevprivate,
1403         .ndo_change_mtu         = ip6_tnl_change_mtu,
1404         .ndo_get_stats64        = dev_get_tstats64,
1405         .ndo_get_iflink         = ip6_tnl_get_iflink,
1406 };
1407
1408 static void ip6gre_dev_free(struct net_device *dev)
1409 {
1410         struct ip6_tnl *t = netdev_priv(dev);
1411
1412         gro_cells_destroy(&t->gro_cells);
1413         dst_cache_destroy(&t->dst_cache);
1414         free_percpu(dev->tstats);
1415 }
1416
1417 static void ip6gre_tunnel_setup(struct net_device *dev)
1418 {
1419         dev->netdev_ops = &ip6gre_netdev_ops;
1420         dev->needs_free_netdev = true;
1421         dev->priv_destructor = ip6gre_dev_free;
1422
1423         dev->type = ARPHRD_IP6GRE;
1424
1425         dev->flags |= IFF_NOARP;
1426         dev->addr_len = sizeof(struct in6_addr);
1427         netif_keep_dst(dev);
1428         /* This perm addr will be used as interface identifier by IPv6 */
1429         dev->addr_assign_type = NET_ADDR_RANDOM;
1430         eth_random_addr(dev->perm_addr);
1431 }
1432
1433 #define GRE6_FEATURES (NETIF_F_SG |             \
1434                        NETIF_F_FRAGLIST |       \
1435                        NETIF_F_HIGHDMA |        \
1436                        NETIF_F_HW_CSUM)
1437
1438 static void ip6gre_tnl_init_features(struct net_device *dev)
1439 {
1440         struct ip6_tnl *nt = netdev_priv(dev);
1441
1442         dev->features           |= GRE6_FEATURES;
1443         dev->hw_features        |= GRE6_FEATURES;
1444
1445         if (!(nt->parms.o_flags & TUNNEL_SEQ)) {
1446                 /* TCP offload with GRE SEQ is not supported, nor
1447                  * can we support 2 levels of outer headers requiring
1448                  * an update.
1449                  */
1450                 if (!(nt->parms.o_flags & TUNNEL_CSUM) ||
1451                     nt->encap.type == TUNNEL_ENCAP_NONE) {
1452                         dev->features    |= NETIF_F_GSO_SOFTWARE;
1453                         dev->hw_features |= NETIF_F_GSO_SOFTWARE;
1454                 }
1455
1456                 /* Can use a lockless transmit, unless we generate
1457                  * output sequences
1458                  */
1459                 dev->features |= NETIF_F_LLTX;
1460         }
1461 }
1462
1463 static int ip6gre_tunnel_init_common(struct net_device *dev)
1464 {
1465         struct ip6_tnl *tunnel;
1466         int ret;
1467         int t_hlen;
1468
1469         tunnel = netdev_priv(dev);
1470
1471         tunnel->dev = dev;
1472         tunnel->net = dev_net(dev);
1473         strcpy(tunnel->parms.name, dev->name);
1474
1475         dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1476         if (!dev->tstats)
1477                 return -ENOMEM;
1478
1479         ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1480         if (ret)
1481                 goto cleanup_alloc_pcpu_stats;
1482
1483         ret = gro_cells_init(&tunnel->gro_cells, dev);
1484         if (ret)
1485                 goto cleanup_dst_cache_init;
1486
1487         t_hlen = ip6gre_calc_hlen(tunnel);
1488         dev->mtu = ETH_DATA_LEN - t_hlen;
1489         if (dev->type == ARPHRD_ETHER)
1490                 dev->mtu -= ETH_HLEN;
1491         if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1492                 dev->mtu -= 8;
1493
1494         if (tunnel->parms.collect_md) {
1495                 netif_keep_dst(dev);
1496         }
1497         ip6gre_tnl_init_features(dev);
1498
1499         dev_hold(dev);
1500         return 0;
1501
1502 cleanup_dst_cache_init:
1503         dst_cache_destroy(&tunnel->dst_cache);
1504 cleanup_alloc_pcpu_stats:
1505         free_percpu(dev->tstats);
1506         dev->tstats = NULL;
1507         return ret;
1508 }
1509
1510 static int ip6gre_tunnel_init(struct net_device *dev)
1511 {
1512         struct ip6_tnl *tunnel;
1513         int ret;
1514
1515         ret = ip6gre_tunnel_init_common(dev);
1516         if (ret)
1517                 return ret;
1518
1519         tunnel = netdev_priv(dev);
1520
1521         if (tunnel->parms.collect_md)
1522                 return 0;
1523
1524         memcpy(dev->dev_addr, &tunnel->parms.laddr, sizeof(struct in6_addr));
1525         memcpy(dev->broadcast, &tunnel->parms.raddr, sizeof(struct in6_addr));
1526
1527         if (ipv6_addr_any(&tunnel->parms.raddr))
1528                 dev->header_ops = &ip6gre_header_ops;
1529
1530         return 0;
1531 }
1532
1533 static void ip6gre_fb_tunnel_init(struct net_device *dev)
1534 {
1535         struct ip6_tnl *tunnel = netdev_priv(dev);
1536
1537         tunnel->dev = dev;
1538         tunnel->net = dev_net(dev);
1539         strcpy(tunnel->parms.name, dev->name);
1540
1541         tunnel->hlen            = sizeof(struct ipv6hdr) + 4;
1542 }
1543
1544 static struct inet6_protocol ip6gre_protocol __read_mostly = {
1545         .handler     = gre_rcv,
1546         .err_handler = ip6gre_err,
1547         .flags       = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
1548 };
1549
1550 static void ip6gre_destroy_tunnels(struct net *net, struct list_head *head)
1551 {
1552         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1553         struct net_device *dev, *aux;
1554         int prio;
1555
1556         for_each_netdev_safe(net, dev, aux)
1557                 if (dev->rtnl_link_ops == &ip6gre_link_ops ||
1558                     dev->rtnl_link_ops == &ip6gre_tap_ops ||
1559                     dev->rtnl_link_ops == &ip6erspan_tap_ops)
1560                         unregister_netdevice_queue(dev, head);
1561
1562         for (prio = 0; prio < 4; prio++) {
1563                 int h;
1564                 for (h = 0; h < IP6_GRE_HASH_SIZE; h++) {
1565                         struct ip6_tnl *t;
1566
1567                         t = rtnl_dereference(ign->tunnels[prio][h]);
1568
1569                         while (t) {
1570                                 /* If dev is in the same netns, it has already
1571                                  * been added to the list by the previous loop.
1572                                  */
1573                                 if (!net_eq(dev_net(t->dev), net))
1574                                         unregister_netdevice_queue(t->dev,
1575                                                                    head);
1576                                 t = rtnl_dereference(t->next);
1577                         }
1578                 }
1579         }
1580 }
1581
1582 static int __net_init ip6gre_init_net(struct net *net)
1583 {
1584         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
1585         struct net_device *ndev;
1586         int err;
1587
1588         if (!net_has_fallback_tunnels(net))
1589                 return 0;
1590         ndev = alloc_netdev(sizeof(struct ip6_tnl), "ip6gre0",
1591                             NET_NAME_UNKNOWN, ip6gre_tunnel_setup);
1592         if (!ndev) {
1593                 err = -ENOMEM;
1594                 goto err_alloc_dev;
1595         }
1596         ign->fb_tunnel_dev = ndev;
1597         dev_net_set(ign->fb_tunnel_dev, net);
1598         /* FB netdevice is special: we have one, and only one per netns.
1599          * Allowing to move it to another netns is clearly unsafe.
1600          */
1601         ign->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL;
1602
1603
1604         ip6gre_fb_tunnel_init(ign->fb_tunnel_dev);
1605         ign->fb_tunnel_dev->rtnl_link_ops = &ip6gre_link_ops;
1606
1607         err = register_netdev(ign->fb_tunnel_dev);
1608         if (err)
1609                 goto err_reg_dev;
1610
1611         rcu_assign_pointer(ign->tunnels_wc[0],
1612                            netdev_priv(ign->fb_tunnel_dev));
1613         return 0;
1614
1615 err_reg_dev:
1616         free_netdev(ndev);
1617 err_alloc_dev:
1618         return err;
1619 }
1620
1621 static void __net_exit ip6gre_exit_batch_net(struct list_head *net_list)
1622 {
1623         struct net *net;
1624         LIST_HEAD(list);
1625
1626         rtnl_lock();
1627         list_for_each_entry(net, net_list, exit_list)
1628                 ip6gre_destroy_tunnels(net, &list);
1629         unregister_netdevice_many(&list);
1630         rtnl_unlock();
1631 }
1632
1633 static struct pernet_operations ip6gre_net_ops = {
1634         .init = ip6gre_init_net,
1635         .exit_batch = ip6gre_exit_batch_net,
1636         .id   = &ip6gre_net_id,
1637         .size = sizeof(struct ip6gre_net),
1638 };
1639
1640 static int ip6gre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[],
1641                                   struct netlink_ext_ack *extack)
1642 {
1643         __be16 flags;
1644
1645         if (!data)
1646                 return 0;
1647
1648         flags = 0;
1649         if (data[IFLA_GRE_IFLAGS])
1650                 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1651         if (data[IFLA_GRE_OFLAGS])
1652                 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1653         if (flags & (GRE_VERSION|GRE_ROUTING))
1654                 return -EINVAL;
1655
1656         return 0;
1657 }
1658
1659 static int ip6gre_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1660                                struct netlink_ext_ack *extack)
1661 {
1662         struct in6_addr daddr;
1663
1664         if (tb[IFLA_ADDRESS]) {
1665                 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
1666                         return -EINVAL;
1667                 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
1668                         return -EADDRNOTAVAIL;
1669         }
1670
1671         if (!data)
1672                 goto out;
1673
1674         if (data[IFLA_GRE_REMOTE]) {
1675                 daddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]);
1676                 if (ipv6_addr_any(&daddr))
1677                         return -EINVAL;
1678         }
1679
1680 out:
1681         return ip6gre_tunnel_validate(tb, data, extack);
1682 }
1683
1684 static int ip6erspan_tap_validate(struct nlattr *tb[], struct nlattr *data[],
1685                                   struct netlink_ext_ack *extack)
1686 {
1687         __be16 flags = 0;
1688         int ret, ver = 0;
1689
1690         if (!data)
1691                 return 0;
1692
1693         ret = ip6gre_tap_validate(tb, data, extack);
1694         if (ret)
1695                 return ret;
1696
1697         /* ERSPAN should only have GRE sequence and key flag */
1698         if (data[IFLA_GRE_OFLAGS])
1699                 flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
1700         if (data[IFLA_GRE_IFLAGS])
1701                 flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
1702         if (!data[IFLA_GRE_COLLECT_METADATA] &&
1703             flags != (GRE_SEQ | GRE_KEY))
1704                 return -EINVAL;
1705
1706         /* ERSPAN Session ID only has 10-bit. Since we reuse
1707          * 32-bit key field as ID, check it's range.
1708          */
1709         if (data[IFLA_GRE_IKEY] &&
1710             (ntohl(nla_get_be32(data[IFLA_GRE_IKEY])) & ~ID_MASK))
1711                 return -EINVAL;
1712
1713         if (data[IFLA_GRE_OKEY] &&
1714             (ntohl(nla_get_be32(data[IFLA_GRE_OKEY])) & ~ID_MASK))
1715                 return -EINVAL;
1716
1717         if (data[IFLA_GRE_ERSPAN_VER]) {
1718                 ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1719                 if (ver != 1 && ver != 2)
1720                         return -EINVAL;
1721         }
1722
1723         if (ver == 1) {
1724                 if (data[IFLA_GRE_ERSPAN_INDEX]) {
1725                         u32 index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1726
1727                         if (index & ~INDEX_MASK)
1728                                 return -EINVAL;
1729                 }
1730         } else if (ver == 2) {
1731                 if (data[IFLA_GRE_ERSPAN_DIR]) {
1732                         u16 dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1733
1734                         if (dir & ~(DIR_MASK >> DIR_OFFSET))
1735                                 return -EINVAL;
1736                 }
1737
1738                 if (data[IFLA_GRE_ERSPAN_HWID]) {
1739                         u16 hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1740
1741                         if (hwid & ~(HWID_MASK >> HWID_OFFSET))
1742                                 return -EINVAL;
1743                 }
1744         }
1745
1746         return 0;
1747 }
1748
1749 static void ip6erspan_set_version(struct nlattr *data[],
1750                                   struct __ip6_tnl_parm *parms)
1751 {
1752         if (!data)
1753                 return;
1754
1755         parms->erspan_ver = 1;
1756         if (data[IFLA_GRE_ERSPAN_VER])
1757                 parms->erspan_ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
1758
1759         if (parms->erspan_ver == 1) {
1760                 if (data[IFLA_GRE_ERSPAN_INDEX])
1761                         parms->index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
1762         } else if (parms->erspan_ver == 2) {
1763                 if (data[IFLA_GRE_ERSPAN_DIR])
1764                         parms->dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]);
1765                 if (data[IFLA_GRE_ERSPAN_HWID])
1766                         parms->hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]);
1767         }
1768 }
1769
1770 static void ip6gre_netlink_parms(struct nlattr *data[],
1771                                 struct __ip6_tnl_parm *parms)
1772 {
1773         memset(parms, 0, sizeof(*parms));
1774
1775         if (!data)
1776                 return;
1777
1778         if (data[IFLA_GRE_LINK])
1779                 parms->link = nla_get_u32(data[IFLA_GRE_LINK]);
1780
1781         if (data[IFLA_GRE_IFLAGS])
1782                 parms->i_flags = gre_flags_to_tnl_flags(
1783                                 nla_get_be16(data[IFLA_GRE_IFLAGS]));
1784
1785         if (data[IFLA_GRE_OFLAGS])
1786                 parms->o_flags = gre_flags_to_tnl_flags(
1787                                 nla_get_be16(data[IFLA_GRE_OFLAGS]));
1788
1789         if (data[IFLA_GRE_IKEY])
1790                 parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]);
1791
1792         if (data[IFLA_GRE_OKEY])
1793                 parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]);
1794
1795         if (data[IFLA_GRE_LOCAL])
1796                 parms->laddr = nla_get_in6_addr(data[IFLA_GRE_LOCAL]);
1797
1798         if (data[IFLA_GRE_REMOTE])
1799                 parms->raddr = nla_get_in6_addr(data[IFLA_GRE_REMOTE]);
1800
1801         if (data[IFLA_GRE_TTL])
1802                 parms->hop_limit = nla_get_u8(data[IFLA_GRE_TTL]);
1803
1804         if (data[IFLA_GRE_ENCAP_LIMIT])
1805                 parms->encap_limit = nla_get_u8(data[IFLA_GRE_ENCAP_LIMIT]);
1806
1807         if (data[IFLA_GRE_FLOWINFO])
1808                 parms->flowinfo = nla_get_be32(data[IFLA_GRE_FLOWINFO]);
1809
1810         if (data[IFLA_GRE_FLAGS])
1811                 parms->flags = nla_get_u32(data[IFLA_GRE_FLAGS]);
1812
1813         if (data[IFLA_GRE_FWMARK])
1814                 parms->fwmark = nla_get_u32(data[IFLA_GRE_FWMARK]);
1815
1816         if (data[IFLA_GRE_COLLECT_METADATA])
1817                 parms->collect_md = true;
1818 }
1819
1820 static int ip6gre_tap_init(struct net_device *dev)
1821 {
1822         int ret;
1823
1824         ret = ip6gre_tunnel_init_common(dev);
1825         if (ret)
1826                 return ret;
1827
1828         dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1829
1830         return 0;
1831 }
1832
1833 static const struct net_device_ops ip6gre_tap_netdev_ops = {
1834         .ndo_init = ip6gre_tap_init,
1835         .ndo_uninit = ip6gre_tunnel_uninit,
1836         .ndo_start_xmit = ip6gre_tunnel_xmit,
1837         .ndo_set_mac_address = eth_mac_addr,
1838         .ndo_validate_addr = eth_validate_addr,
1839         .ndo_change_mtu = ip6_tnl_change_mtu,
1840         .ndo_get_stats64 = dev_get_tstats64,
1841         .ndo_get_iflink = ip6_tnl_get_iflink,
1842 };
1843
1844 static int ip6erspan_calc_hlen(struct ip6_tnl *tunnel)
1845 {
1846         int t_hlen;
1847
1848         tunnel->tun_hlen = 8;
1849         tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen +
1850                        erspan_hdr_len(tunnel->parms.erspan_ver);
1851
1852         t_hlen = tunnel->hlen + sizeof(struct ipv6hdr);
1853         tunnel->dev->needed_headroom = LL_MAX_HEADER + t_hlen;
1854         return t_hlen;
1855 }
1856
1857 static int ip6erspan_tap_init(struct net_device *dev)
1858 {
1859         struct ip6_tnl *tunnel;
1860         int t_hlen;
1861         int ret;
1862
1863         tunnel = netdev_priv(dev);
1864
1865         tunnel->dev = dev;
1866         tunnel->net = dev_net(dev);
1867         strcpy(tunnel->parms.name, dev->name);
1868
1869         dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1870         if (!dev->tstats)
1871                 return -ENOMEM;
1872
1873         ret = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
1874         if (ret)
1875                 goto cleanup_alloc_pcpu_stats;
1876
1877         ret = gro_cells_init(&tunnel->gro_cells, dev);
1878         if (ret)
1879                 goto cleanup_dst_cache_init;
1880
1881         t_hlen = ip6erspan_calc_hlen(tunnel);
1882         dev->mtu = ETH_DATA_LEN - t_hlen;
1883         if (dev->type == ARPHRD_ETHER)
1884                 dev->mtu -= ETH_HLEN;
1885         if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
1886                 dev->mtu -= 8;
1887
1888         dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1889         ip6erspan_tnl_link_config(tunnel, 1);
1890
1891         dev_hold(dev);
1892         return 0;
1893
1894 cleanup_dst_cache_init:
1895         dst_cache_destroy(&tunnel->dst_cache);
1896 cleanup_alloc_pcpu_stats:
1897         free_percpu(dev->tstats);
1898         dev->tstats = NULL;
1899         return ret;
1900 }
1901
1902 static const struct net_device_ops ip6erspan_netdev_ops = {
1903         .ndo_init =             ip6erspan_tap_init,
1904         .ndo_uninit =           ip6erspan_tunnel_uninit,
1905         .ndo_start_xmit =       ip6erspan_tunnel_xmit,
1906         .ndo_set_mac_address =  eth_mac_addr,
1907         .ndo_validate_addr =    eth_validate_addr,
1908         .ndo_change_mtu =       ip6_tnl_change_mtu,
1909         .ndo_get_stats64 =      dev_get_tstats64,
1910         .ndo_get_iflink =       ip6_tnl_get_iflink,
1911 };
1912
1913 static void ip6gre_tap_setup(struct net_device *dev)
1914 {
1915
1916         ether_setup(dev);
1917
1918         dev->max_mtu = 0;
1919         dev->netdev_ops = &ip6gre_tap_netdev_ops;
1920         dev->needs_free_netdev = true;
1921         dev->priv_destructor = ip6gre_dev_free;
1922
1923         dev->priv_flags &= ~IFF_TX_SKB_SHARING;
1924         dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
1925         netif_keep_dst(dev);
1926 }
1927
1928 static bool ip6gre_netlink_encap_parms(struct nlattr *data[],
1929                                        struct ip_tunnel_encap *ipencap)
1930 {
1931         bool ret = false;
1932
1933         memset(ipencap, 0, sizeof(*ipencap));
1934
1935         if (!data)
1936                 return ret;
1937
1938         if (data[IFLA_GRE_ENCAP_TYPE]) {
1939                 ret = true;
1940                 ipencap->type = nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]);
1941         }
1942
1943         if (data[IFLA_GRE_ENCAP_FLAGS]) {
1944                 ret = true;
1945                 ipencap->flags = nla_get_u16(data[IFLA_GRE_ENCAP_FLAGS]);
1946         }
1947
1948         if (data[IFLA_GRE_ENCAP_SPORT]) {
1949                 ret = true;
1950                 ipencap->sport = nla_get_be16(data[IFLA_GRE_ENCAP_SPORT]);
1951         }
1952
1953         if (data[IFLA_GRE_ENCAP_DPORT]) {
1954                 ret = true;
1955                 ipencap->dport = nla_get_be16(data[IFLA_GRE_ENCAP_DPORT]);
1956         }
1957
1958         return ret;
1959 }
1960
1961 static int ip6gre_newlink_common(struct net *src_net, struct net_device *dev,
1962                                  struct nlattr *tb[], struct nlattr *data[],
1963                                  struct netlink_ext_ack *extack)
1964 {
1965         struct ip6_tnl *nt;
1966         struct ip_tunnel_encap ipencap;
1967         int err;
1968
1969         nt = netdev_priv(dev);
1970
1971         if (ip6gre_netlink_encap_parms(data, &ipencap)) {
1972                 int err = ip6_tnl_encap_setup(nt, &ipencap);
1973
1974                 if (err < 0)
1975                         return err;
1976         }
1977
1978         if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS])
1979                 eth_hw_addr_random(dev);
1980
1981         nt->dev = dev;
1982         nt->net = dev_net(dev);
1983
1984         err = register_netdevice(dev);
1985         if (err)
1986                 goto out;
1987
1988         if (tb[IFLA_MTU])
1989                 ip6_tnl_change_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
1990
1991 out:
1992         return err;
1993 }
1994
1995 static int ip6gre_newlink(struct net *src_net, struct net_device *dev,
1996                           struct nlattr *tb[], struct nlattr *data[],
1997                           struct netlink_ext_ack *extack)
1998 {
1999         struct ip6_tnl *nt = netdev_priv(dev);
2000         struct net *net = dev_net(dev);
2001         struct ip6gre_net *ign;
2002         int err;
2003
2004         ip6gre_netlink_parms(data, &nt->parms);
2005         ign = net_generic(net, ip6gre_net_id);
2006
2007         if (nt->parms.collect_md) {
2008                 if (rtnl_dereference(ign->collect_md_tun))
2009                         return -EEXIST;
2010         } else {
2011                 if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
2012                         return -EEXIST;
2013         }
2014
2015         err = ip6gre_newlink_common(src_net, dev, tb, data, extack);
2016         if (!err) {
2017                 ip6gre_tnl_link_config(nt, !tb[IFLA_MTU]);
2018                 ip6gre_tunnel_link_md(ign, nt);
2019                 ip6gre_tunnel_link(net_generic(net, ip6gre_net_id), nt);
2020         }
2021         return err;
2022 }
2023
2024 static struct ip6_tnl *
2025 ip6gre_changelink_common(struct net_device *dev, struct nlattr *tb[],
2026                          struct nlattr *data[], struct __ip6_tnl_parm *p_p,
2027                          struct netlink_ext_ack *extack)
2028 {
2029         struct ip6_tnl *t, *nt = netdev_priv(dev);
2030         struct net *net = nt->net;
2031         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
2032         struct ip_tunnel_encap ipencap;
2033
2034         if (dev == ign->fb_tunnel_dev)
2035                 return ERR_PTR(-EINVAL);
2036
2037         if (ip6gre_netlink_encap_parms(data, &ipencap)) {
2038                 int err = ip6_tnl_encap_setup(nt, &ipencap);
2039
2040                 if (err < 0)
2041                         return ERR_PTR(err);
2042         }
2043
2044         ip6gre_netlink_parms(data, p_p);
2045
2046         t = ip6gre_tunnel_locate(net, p_p, 0);
2047
2048         if (t) {
2049                 if (t->dev != dev)
2050                         return ERR_PTR(-EEXIST);
2051         } else {
2052                 t = nt;
2053         }
2054
2055         return t;
2056 }
2057
2058 static int ip6gre_changelink(struct net_device *dev, struct nlattr *tb[],
2059                              struct nlattr *data[],
2060                              struct netlink_ext_ack *extack)
2061 {
2062         struct ip6_tnl *t = netdev_priv(dev);
2063         struct ip6gre_net *ign = net_generic(t->net, ip6gre_net_id);
2064         struct __ip6_tnl_parm p;
2065
2066         t = ip6gre_changelink_common(dev, tb, data, &p, extack);
2067         if (IS_ERR(t))
2068                 return PTR_ERR(t);
2069
2070         ip6gre_tunnel_unlink_md(ign, t);
2071         ip6gre_tunnel_unlink(ign, t);
2072         ip6gre_tnl_change(t, &p, !tb[IFLA_MTU]);
2073         ip6gre_tunnel_link_md(ign, t);
2074         ip6gre_tunnel_link(ign, t);
2075         return 0;
2076 }
2077
2078 static void ip6gre_dellink(struct net_device *dev, struct list_head *head)
2079 {
2080         struct net *net = dev_net(dev);
2081         struct ip6gre_net *ign = net_generic(net, ip6gre_net_id);
2082
2083         if (dev != ign->fb_tunnel_dev)
2084                 unregister_netdevice_queue(dev, head);
2085 }
2086
2087 static size_t ip6gre_get_size(const struct net_device *dev)
2088 {
2089         return
2090                 /* IFLA_GRE_LINK */
2091                 nla_total_size(4) +
2092                 /* IFLA_GRE_IFLAGS */
2093                 nla_total_size(2) +
2094                 /* IFLA_GRE_OFLAGS */
2095                 nla_total_size(2) +
2096                 /* IFLA_GRE_IKEY */
2097                 nla_total_size(4) +
2098                 /* IFLA_GRE_OKEY */
2099                 nla_total_size(4) +
2100                 /* IFLA_GRE_LOCAL */
2101                 nla_total_size(sizeof(struct in6_addr)) +
2102                 /* IFLA_GRE_REMOTE */
2103                 nla_total_size(sizeof(struct in6_addr)) +
2104                 /* IFLA_GRE_TTL */
2105                 nla_total_size(1) +
2106                 /* IFLA_GRE_ENCAP_LIMIT */
2107                 nla_total_size(1) +
2108                 /* IFLA_GRE_FLOWINFO */
2109                 nla_total_size(4) +
2110                 /* IFLA_GRE_FLAGS */
2111                 nla_total_size(4) +
2112                 /* IFLA_GRE_ENCAP_TYPE */
2113                 nla_total_size(2) +
2114                 /* IFLA_GRE_ENCAP_FLAGS */
2115                 nla_total_size(2) +
2116                 /* IFLA_GRE_ENCAP_SPORT */
2117                 nla_total_size(2) +
2118                 /* IFLA_GRE_ENCAP_DPORT */
2119                 nla_total_size(2) +
2120                 /* IFLA_GRE_COLLECT_METADATA */
2121                 nla_total_size(0) +
2122                 /* IFLA_GRE_FWMARK */
2123                 nla_total_size(4) +
2124                 /* IFLA_GRE_ERSPAN_INDEX */
2125                 nla_total_size(4) +
2126                 0;
2127 }
2128
2129 static int ip6gre_fill_info(struct sk_buff *skb, const struct net_device *dev)
2130 {
2131         struct ip6_tnl *t = netdev_priv(dev);
2132         struct __ip6_tnl_parm *p = &t->parms;
2133         __be16 o_flags = p->o_flags;
2134
2135         if (p->erspan_ver == 1 || p->erspan_ver == 2) {
2136                 if (!p->collect_md)
2137                         o_flags |= TUNNEL_KEY;
2138
2139                 if (nla_put_u8(skb, IFLA_GRE_ERSPAN_VER, p->erspan_ver))
2140                         goto nla_put_failure;
2141
2142                 if (p->erspan_ver == 1) {
2143                         if (nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, p->index))
2144                                 goto nla_put_failure;
2145                 } else {
2146                         if (nla_put_u8(skb, IFLA_GRE_ERSPAN_DIR, p->dir))
2147                                 goto nla_put_failure;
2148                         if (nla_put_u16(skb, IFLA_GRE_ERSPAN_HWID, p->hwid))
2149                                 goto nla_put_failure;
2150                 }
2151         }
2152
2153         if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) ||
2154             nla_put_be16(skb, IFLA_GRE_IFLAGS,
2155                          gre_tnl_flags_to_gre_flags(p->i_flags)) ||
2156             nla_put_be16(skb, IFLA_GRE_OFLAGS,
2157                          gre_tnl_flags_to_gre_flags(o_flags)) ||
2158             nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) ||
2159             nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) ||
2160             nla_put_in6_addr(skb, IFLA_GRE_LOCAL, &p->laddr) ||
2161             nla_put_in6_addr(skb, IFLA_GRE_REMOTE, &p->raddr) ||
2162             nla_put_u8(skb, IFLA_GRE_TTL, p->hop_limit) ||
2163             nla_put_u8(skb, IFLA_GRE_ENCAP_LIMIT, p->encap_limit) ||
2164             nla_put_be32(skb, IFLA_GRE_FLOWINFO, p->flowinfo) ||
2165             nla_put_u32(skb, IFLA_GRE_FLAGS, p->flags) ||
2166             nla_put_u32(skb, IFLA_GRE_FWMARK, p->fwmark))
2167                 goto nla_put_failure;
2168
2169         if (nla_put_u16(skb, IFLA_GRE_ENCAP_TYPE,
2170                         t->encap.type) ||
2171             nla_put_be16(skb, IFLA_GRE_ENCAP_SPORT,
2172                          t->encap.sport) ||
2173             nla_put_be16(skb, IFLA_GRE_ENCAP_DPORT,
2174                          t->encap.dport) ||
2175             nla_put_u16(skb, IFLA_GRE_ENCAP_FLAGS,
2176                         t->encap.flags))
2177                 goto nla_put_failure;
2178
2179         if (p->collect_md) {
2180                 if (nla_put_flag(skb, IFLA_GRE_COLLECT_METADATA))
2181                         goto nla_put_failure;
2182         }
2183
2184         return 0;
2185
2186 nla_put_failure:
2187         return -EMSGSIZE;
2188 }
2189
2190 static const struct nla_policy ip6gre_policy[IFLA_GRE_MAX + 1] = {
2191         [IFLA_GRE_LINK]        = { .type = NLA_U32 },
2192         [IFLA_GRE_IFLAGS]      = { .type = NLA_U16 },
2193         [IFLA_GRE_OFLAGS]      = { .type = NLA_U16 },
2194         [IFLA_GRE_IKEY]        = { .type = NLA_U32 },
2195         [IFLA_GRE_OKEY]        = { .type = NLA_U32 },
2196         [IFLA_GRE_LOCAL]       = { .len = sizeof_field(struct ipv6hdr, saddr) },
2197         [IFLA_GRE_REMOTE]      = { .len = sizeof_field(struct ipv6hdr, daddr) },
2198         [IFLA_GRE_TTL]         = { .type = NLA_U8 },
2199         [IFLA_GRE_ENCAP_LIMIT] = { .type = NLA_U8 },
2200         [IFLA_GRE_FLOWINFO]    = { .type = NLA_U32 },
2201         [IFLA_GRE_FLAGS]       = { .type = NLA_U32 },
2202         [IFLA_GRE_ENCAP_TYPE]   = { .type = NLA_U16 },
2203         [IFLA_GRE_ENCAP_FLAGS]  = { .type = NLA_U16 },
2204         [IFLA_GRE_ENCAP_SPORT]  = { .type = NLA_U16 },
2205         [IFLA_GRE_ENCAP_DPORT]  = { .type = NLA_U16 },
2206         [IFLA_GRE_COLLECT_METADATA] = { .type = NLA_FLAG },
2207         [IFLA_GRE_FWMARK]       = { .type = NLA_U32 },
2208         [IFLA_GRE_ERSPAN_INDEX] = { .type = NLA_U32 },
2209         [IFLA_GRE_ERSPAN_VER]   = { .type = NLA_U8 },
2210         [IFLA_GRE_ERSPAN_DIR]   = { .type = NLA_U8 },
2211         [IFLA_GRE_ERSPAN_HWID]  = { .type = NLA_U16 },
2212 };
2213
2214 static void ip6erspan_tap_setup(struct net_device *dev)
2215 {
2216         ether_setup(dev);
2217
2218         dev->max_mtu = 0;
2219         dev->netdev_ops = &ip6erspan_netdev_ops;
2220         dev->needs_free_netdev = true;
2221         dev->priv_destructor = ip6gre_dev_free;
2222
2223         dev->priv_flags &= ~IFF_TX_SKB_SHARING;
2224         dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
2225         netif_keep_dst(dev);
2226 }
2227
2228 static int ip6erspan_newlink(struct net *src_net, struct net_device *dev,
2229                              struct nlattr *tb[], struct nlattr *data[],
2230                              struct netlink_ext_ack *extack)
2231 {
2232         struct ip6_tnl *nt = netdev_priv(dev);
2233         struct net *net = dev_net(dev);
2234         struct ip6gre_net *ign;
2235         int err;
2236
2237         ip6gre_netlink_parms(data, &nt->parms);
2238         ip6erspan_set_version(data, &nt->parms);
2239         ign = net_generic(net, ip6gre_net_id);
2240
2241         if (nt->parms.collect_md) {
2242                 if (rtnl_dereference(ign->collect_md_tun_erspan))
2243                         return -EEXIST;
2244         } else {
2245                 if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
2246                         return -EEXIST;
2247         }
2248
2249         err = ip6gre_newlink_common(src_net, dev, tb, data, extack);
2250         if (!err) {
2251                 ip6erspan_tnl_link_config(nt, !tb[IFLA_MTU]);
2252                 ip6erspan_tunnel_link_md(ign, nt);
2253                 ip6gre_tunnel_link(net_generic(net, ip6gre_net_id), nt);
2254         }
2255         return err;
2256 }
2257
2258 static void ip6erspan_tnl_link_config(struct ip6_tnl *t, int set_mtu)
2259 {
2260         ip6gre_tnl_link_config_common(t);
2261         ip6gre_tnl_link_config_route(t, set_mtu, ip6erspan_calc_hlen(t));
2262 }
2263
2264 static int ip6erspan_tnl_change(struct ip6_tnl *t,
2265                                 const struct __ip6_tnl_parm *p, int set_mtu)
2266 {
2267         ip6gre_tnl_copy_tnl_parm(t, p);
2268         ip6erspan_tnl_link_config(t, set_mtu);
2269         return 0;
2270 }
2271
2272 static int ip6erspan_changelink(struct net_device *dev, struct nlattr *tb[],
2273                                 struct nlattr *data[],
2274                                 struct netlink_ext_ack *extack)
2275 {
2276         struct ip6gre_net *ign = net_generic(dev_net(dev), ip6gre_net_id);
2277         struct __ip6_tnl_parm p;
2278         struct ip6_tnl *t;
2279
2280         t = ip6gre_changelink_common(dev, tb, data, &p, extack);
2281         if (IS_ERR(t))
2282                 return PTR_ERR(t);
2283
2284         ip6erspan_set_version(data, &p);
2285         ip6gre_tunnel_unlink_md(ign, t);
2286         ip6gre_tunnel_unlink(ign, t);
2287         ip6erspan_tnl_change(t, &p, !tb[IFLA_MTU]);
2288         ip6erspan_tunnel_link_md(ign, t);
2289         ip6gre_tunnel_link(ign, t);
2290         return 0;
2291 }
2292
2293 static struct rtnl_link_ops ip6gre_link_ops __read_mostly = {
2294         .kind           = "ip6gre",
2295         .maxtype        = IFLA_GRE_MAX,
2296         .policy         = ip6gre_policy,
2297         .priv_size      = sizeof(struct ip6_tnl),
2298         .setup          = ip6gre_tunnel_setup,
2299         .validate       = ip6gre_tunnel_validate,
2300         .newlink        = ip6gre_newlink,
2301         .changelink     = ip6gre_changelink,
2302         .dellink        = ip6gre_dellink,
2303         .get_size       = ip6gre_get_size,
2304         .fill_info      = ip6gre_fill_info,
2305         .get_link_net   = ip6_tnl_get_link_net,
2306 };
2307
2308 static struct rtnl_link_ops ip6gre_tap_ops __read_mostly = {
2309         .kind           = "ip6gretap",
2310         .maxtype        = IFLA_GRE_MAX,
2311         .policy         = ip6gre_policy,
2312         .priv_size      = sizeof(struct ip6_tnl),
2313         .setup          = ip6gre_tap_setup,
2314         .validate       = ip6gre_tap_validate,
2315         .newlink        = ip6gre_newlink,
2316         .changelink     = ip6gre_changelink,
2317         .get_size       = ip6gre_get_size,
2318         .fill_info      = ip6gre_fill_info,
2319         .get_link_net   = ip6_tnl_get_link_net,
2320 };
2321
2322 static struct rtnl_link_ops ip6erspan_tap_ops __read_mostly = {
2323         .kind           = "ip6erspan",
2324         .maxtype        = IFLA_GRE_MAX,
2325         .policy         = ip6gre_policy,
2326         .priv_size      = sizeof(struct ip6_tnl),
2327         .setup          = ip6erspan_tap_setup,
2328         .validate       = ip6erspan_tap_validate,
2329         .newlink        = ip6erspan_newlink,
2330         .changelink     = ip6erspan_changelink,
2331         .get_size       = ip6gre_get_size,
2332         .fill_info      = ip6gre_fill_info,
2333         .get_link_net   = ip6_tnl_get_link_net,
2334 };
2335
2336 /*
2337  *      And now the modules code and kernel interface.
2338  */
2339
2340 static int __init ip6gre_init(void)
2341 {
2342         int err;
2343
2344         pr_info("GRE over IPv6 tunneling driver\n");
2345
2346         err = register_pernet_device(&ip6gre_net_ops);
2347         if (err < 0)
2348                 return err;
2349
2350         err = inet6_add_protocol(&ip6gre_protocol, IPPROTO_GRE);
2351         if (err < 0) {
2352                 pr_info("%s: can't add protocol\n", __func__);
2353                 goto add_proto_failed;
2354         }
2355
2356         err = rtnl_link_register(&ip6gre_link_ops);
2357         if (err < 0)
2358                 goto rtnl_link_failed;
2359
2360         err = rtnl_link_register(&ip6gre_tap_ops);
2361         if (err < 0)
2362                 goto tap_ops_failed;
2363
2364         err = rtnl_link_register(&ip6erspan_tap_ops);
2365         if (err < 0)
2366                 goto erspan_link_failed;
2367
2368 out:
2369         return err;
2370
2371 erspan_link_failed:
2372         rtnl_link_unregister(&ip6gre_tap_ops);
2373 tap_ops_failed:
2374         rtnl_link_unregister(&ip6gre_link_ops);
2375 rtnl_link_failed:
2376         inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
2377 add_proto_failed:
2378         unregister_pernet_device(&ip6gre_net_ops);
2379         goto out;
2380 }
2381
2382 static void __exit ip6gre_fini(void)
2383 {
2384         rtnl_link_unregister(&ip6gre_tap_ops);
2385         rtnl_link_unregister(&ip6gre_link_ops);
2386         rtnl_link_unregister(&ip6erspan_tap_ops);
2387         inet6_del_protocol(&ip6gre_protocol, IPPROTO_GRE);
2388         unregister_pernet_device(&ip6gre_net_ops);
2389 }
2390
2391 module_init(ip6gre_init);
2392 module_exit(ip6gre_fini);
2393 MODULE_LICENSE("GPL");
2394 MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)");
2395 MODULE_DESCRIPTION("GRE over IPv6 tunneling device");
2396 MODULE_ALIAS_RTNL_LINK("ip6gre");
2397 MODULE_ALIAS_RTNL_LINK("ip6gretap");
2398 MODULE_ALIAS_RTNL_LINK("ip6erspan");
2399 MODULE_ALIAS_NETDEV("ip6gre0");