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1 | /* | |
2 | * Linux NET3: GRE over IP protocol decoder. | |
3 | * | |
4 | * Authors: Alexey Kuznetsov (kuznet@ms2.inr.ac.ru) | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or | |
7 | * modify it under the terms of the GNU General Public License | |
8 | * as published by the Free Software Foundation; either version | |
9 | * 2 of the License, or (at your option) any later version. | |
10 | * | |
11 | */ | |
12 | ||
13 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt | |
14 | ||
15 | #include <linux/capability.h> | |
16 | #include <linux/module.h> | |
17 | #include <linux/types.h> | |
18 | #include <linux/kernel.h> | |
19 | #include <linux/slab.h> | |
20 | #include <asm/uaccess.h> | |
21 | #include <linux/skbuff.h> | |
22 | #include <linux/netdevice.h> | |
23 | #include <linux/in.h> | |
24 | #include <linux/tcp.h> | |
25 | #include <linux/udp.h> | |
26 | #include <linux/if_arp.h> | |
27 | #include <linux/if_vlan.h> | |
28 | #include <linux/init.h> | |
29 | #include <linux/in6.h> | |
30 | #include <linux/inetdevice.h> | |
31 | #include <linux/igmp.h> | |
32 | #include <linux/netfilter_ipv4.h> | |
33 | #include <linux/etherdevice.h> | |
34 | #include <linux/if_ether.h> | |
35 | ||
36 | #include <net/sock.h> | |
37 | #include <net/ip.h> | |
38 | #include <net/icmp.h> | |
39 | #include <net/protocol.h> | |
40 | #include <net/ip_tunnels.h> | |
41 | #include <net/arp.h> | |
42 | #include <net/checksum.h> | |
43 | #include <net/dsfield.h> | |
44 | #include <net/inet_ecn.h> | |
45 | #include <net/xfrm.h> | |
46 | #include <net/net_namespace.h> | |
47 | #include <net/netns/generic.h> | |
48 | #include <net/rtnetlink.h> | |
49 | #include <net/gre.h> | |
50 | #include <net/dst_metadata.h> | |
51 | ||
52 | #if IS_ENABLED(CONFIG_IPV6) | |
53 | #include <net/ipv6.h> | |
54 | #include <net/ip6_fib.h> | |
55 | #include <net/ip6_route.h> | |
56 | #endif | |
57 | ||
58 | /* | |
59 | Problems & solutions | |
60 | -------------------- | |
61 | ||
62 | 1. The most important issue is detecting local dead loops. | |
63 | They would cause complete host lockup in transmit, which | |
64 | would be "resolved" by stack overflow or, if queueing is enabled, | |
65 | with infinite looping in net_bh. | |
66 | ||
67 | We cannot track such dead loops during route installation, | |
68 | it is infeasible task. The most general solutions would be | |
69 | to keep skb->encapsulation counter (sort of local ttl), | |
70 | and silently drop packet when it expires. It is a good | |
71 | solution, but it supposes maintaining new variable in ALL | |
72 | skb, even if no tunneling is used. | |
73 | ||
74 | Current solution: xmit_recursion breaks dead loops. This is a percpu | |
75 | counter, since when we enter the first ndo_xmit(), cpu migration is | |
76 | forbidden. We force an exit if this counter reaches RECURSION_LIMIT | |
77 | ||
78 | 2. Networking dead loops would not kill routers, but would really | |
79 | kill network. IP hop limit plays role of "t->recursion" in this case, | |
80 | if we copy it from packet being encapsulated to upper header. | |
81 | It is very good solution, but it introduces two problems: | |
82 | ||
83 | - Routing protocols, using packets with ttl=1 (OSPF, RIP2), | |
84 | do not work over tunnels. | |
85 | - traceroute does not work. I planned to relay ICMP from tunnel, | |
86 | so that this problem would be solved and traceroute output | |
87 | would even more informative. This idea appeared to be wrong: | |
88 | only Linux complies to rfc1812 now (yes, guys, Linux is the only | |
89 | true router now :-)), all routers (at least, in neighbourhood of mine) | |
90 | return only 8 bytes of payload. It is the end. | |
91 | ||
92 | Hence, if we want that OSPF worked or traceroute said something reasonable, | |
93 | we should search for another solution. | |
94 | ||
95 | One of them is to parse packet trying to detect inner encapsulation | |
96 | made by our node. It is difficult or even impossible, especially, | |
97 | taking into account fragmentation. TO be short, ttl is not solution at all. | |
98 | ||
99 | Current solution: The solution was UNEXPECTEDLY SIMPLE. | |
100 | We force DF flag on tunnels with preconfigured hop limit, | |
101 | that is ALL. :-) Well, it does not remove the problem completely, | |
102 | but exponential growth of network traffic is changed to linear | |
103 | (branches, that exceed pmtu are pruned) and tunnel mtu | |
104 | rapidly degrades to value <68, where looping stops. | |
105 | Yes, it is not good if there exists a router in the loop, | |
106 | which does not force DF, even when encapsulating packets have DF set. | |
107 | But it is not our problem! Nobody could accuse us, we made | |
108 | all that we could make. Even if it is your gated who injected | |
109 | fatal route to network, even if it were you who configured | |
110 | fatal static route: you are innocent. :-) | |
111 | ||
112 | Alexey Kuznetsov. | |
113 | */ | |
114 | ||
115 | static bool log_ecn_error = true; | |
116 | module_param(log_ecn_error, bool, 0644); | |
117 | MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN"); | |
118 | ||
119 | static struct rtnl_link_ops ipgre_link_ops __read_mostly; | |
120 | static int ipgre_tunnel_init(struct net_device *dev); | |
121 | ||
122 | static int ipgre_net_id __read_mostly; | |
123 | static int gre_tap_net_id __read_mostly; | |
124 | ||
125 | static void ipgre_err(struct sk_buff *skb, u32 info, | |
126 | const struct tnl_ptk_info *tpi) | |
127 | { | |
128 | ||
129 | /* All the routers (except for Linux) return only | |
130 | 8 bytes of packet payload. It means, that precise relaying of | |
131 | ICMP in the real Internet is absolutely infeasible. | |
132 | ||
133 | Moreover, Cisco "wise men" put GRE key to the third word | |
134 | in GRE header. It makes impossible maintaining even soft | |
135 | state for keyed GRE tunnels with enabled checksum. Tell | |
136 | them "thank you". | |
137 | ||
138 | Well, I wonder, rfc1812 was written by Cisco employee, | |
139 | what the hell these idiots break standards established | |
140 | by themselves??? | |
141 | */ | |
142 | struct net *net = dev_net(skb->dev); | |
143 | struct ip_tunnel_net *itn; | |
144 | const struct iphdr *iph; | |
145 | const int type = icmp_hdr(skb)->type; | |
146 | const int code = icmp_hdr(skb)->code; | |
147 | struct ip_tunnel *t; | |
148 | ||
149 | switch (type) { | |
150 | default: | |
151 | case ICMP_PARAMETERPROB: | |
152 | return; | |
153 | ||
154 | case ICMP_DEST_UNREACH: | |
155 | switch (code) { | |
156 | case ICMP_SR_FAILED: | |
157 | case ICMP_PORT_UNREACH: | |
158 | /* Impossible event. */ | |
159 | return; | |
160 | default: | |
161 | /* All others are translated to HOST_UNREACH. | |
162 | rfc2003 contains "deep thoughts" about NET_UNREACH, | |
163 | I believe they are just ether pollution. --ANK | |
164 | */ | |
165 | break; | |
166 | } | |
167 | break; | |
168 | ||
169 | case ICMP_TIME_EXCEEDED: | |
170 | if (code != ICMP_EXC_TTL) | |
171 | return; | |
172 | break; | |
173 | ||
174 | case ICMP_REDIRECT: | |
175 | break; | |
176 | } | |
177 | ||
178 | if (tpi->proto == htons(ETH_P_TEB)) | |
179 | itn = net_generic(net, gre_tap_net_id); | |
180 | else | |
181 | itn = net_generic(net, ipgre_net_id); | |
182 | ||
183 | iph = (const struct iphdr *)(icmp_hdr(skb) + 1); | |
184 | t = ip_tunnel_lookup(itn, skb->dev->ifindex, tpi->flags, | |
185 | iph->daddr, iph->saddr, tpi->key); | |
186 | ||
187 | if (!t) | |
188 | return; | |
189 | ||
190 | if (t->parms.iph.daddr == 0 || | |
191 | ipv4_is_multicast(t->parms.iph.daddr)) | |
192 | return; | |
193 | ||
194 | if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED) | |
195 | return; | |
196 | ||
197 | if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO)) | |
198 | t->err_count++; | |
199 | else | |
200 | t->err_count = 1; | |
201 | t->err_time = jiffies; | |
202 | } | |
203 | ||
204 | static void gre_err(struct sk_buff *skb, u32 info) | |
205 | { | |
206 | /* All the routers (except for Linux) return only | |
207 | * 8 bytes of packet payload. It means, that precise relaying of | |
208 | * ICMP in the real Internet is absolutely infeasible. | |
209 | * | |
210 | * Moreover, Cisco "wise men" put GRE key to the third word | |
211 | * in GRE header. It makes impossible maintaining even soft | |
212 | * state for keyed | |
213 | * GRE tunnels with enabled checksum. Tell them "thank you". | |
214 | * | |
215 | * Well, I wonder, rfc1812 was written by Cisco employee, | |
216 | * what the hell these idiots break standards established | |
217 | * by themselves??? | |
218 | */ | |
219 | ||
220 | const int type = icmp_hdr(skb)->type; | |
221 | const int code = icmp_hdr(skb)->code; | |
222 | struct tnl_ptk_info tpi; | |
223 | bool csum_err = false; | |
224 | ||
225 | if (gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IP)) < 0) { | |
226 | if (!csum_err) /* ignore csum errors. */ | |
227 | return; | |
228 | } | |
229 | ||
230 | if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) { | |
231 | ipv4_update_pmtu(skb, dev_net(skb->dev), info, | |
232 | skb->dev->ifindex, 0, IPPROTO_GRE, 0); | |
233 | return; | |
234 | } | |
235 | if (type == ICMP_REDIRECT) { | |
236 | ipv4_redirect(skb, dev_net(skb->dev), skb->dev->ifindex, 0, | |
237 | IPPROTO_GRE, 0); | |
238 | return; | |
239 | } | |
240 | ||
241 | ipgre_err(skb, info, &tpi); | |
242 | } | |
243 | ||
244 | static __be64 key_to_tunnel_id(__be32 key) | |
245 | { | |
246 | #ifdef __BIG_ENDIAN | |
247 | return (__force __be64)((__force u32)key); | |
248 | #else | |
249 | return (__force __be64)((__force u64)key << 32); | |
250 | #endif | |
251 | } | |
252 | ||
253 | /* Returns the least-significant 32 bits of a __be64. */ | |
254 | static __be32 tunnel_id_to_key(__be64 x) | |
255 | { | |
256 | #ifdef __BIG_ENDIAN | |
257 | return (__force __be32)x; | |
258 | #else | |
259 | return (__force __be32)((__force u64)x >> 32); | |
260 | #endif | |
261 | } | |
262 | ||
263 | static int __ipgre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi, | |
264 | struct ip_tunnel_net *itn, int hdr_len, bool raw_proto) | |
265 | { | |
266 | struct metadata_dst *tun_dst = NULL; | |
267 | const struct iphdr *iph; | |
268 | struct ip_tunnel *tunnel; | |
269 | ||
270 | iph = ip_hdr(skb); | |
271 | tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, tpi->flags, | |
272 | iph->saddr, iph->daddr, tpi->key); | |
273 | ||
274 | if (tunnel) { | |
275 | if (__iptunnel_pull_header(skb, hdr_len, tpi->proto, | |
276 | raw_proto, false) < 0) | |
277 | goto drop; | |
278 | ||
279 | if (tunnel->dev->type != ARPHRD_NONE) | |
280 | skb_pop_mac_header(skb); | |
281 | else | |
282 | skb_reset_mac_header(skb); | |
283 | if (tunnel->collect_md) { | |
284 | __be16 flags; | |
285 | __be64 tun_id; | |
286 | ||
287 | flags = tpi->flags & (TUNNEL_CSUM | TUNNEL_KEY); | |
288 | tun_id = key_to_tunnel_id(tpi->key); | |
289 | tun_dst = ip_tun_rx_dst(skb, flags, tun_id, 0); | |
290 | if (!tun_dst) | |
291 | return PACKET_REJECT; | |
292 | } | |
293 | ||
294 | ip_tunnel_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error); | |
295 | return PACKET_RCVD; | |
296 | } | |
297 | return PACKET_NEXT; | |
298 | ||
299 | drop: | |
300 | kfree_skb(skb); | |
301 | return PACKET_RCVD; | |
302 | } | |
303 | ||
304 | static int ipgre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi, | |
305 | int hdr_len) | |
306 | { | |
307 | struct net *net = dev_net(skb->dev); | |
308 | struct ip_tunnel_net *itn; | |
309 | int res; | |
310 | ||
311 | if (tpi->proto == htons(ETH_P_TEB)) | |
312 | itn = net_generic(net, gre_tap_net_id); | |
313 | else | |
314 | itn = net_generic(net, ipgre_net_id); | |
315 | ||
316 | res = __ipgre_rcv(skb, tpi, itn, hdr_len, false); | |
317 | if (res == PACKET_NEXT && tpi->proto == htons(ETH_P_TEB)) { | |
318 | /* ipgre tunnels in collect metadata mode should receive | |
319 | * also ETH_P_TEB traffic. | |
320 | */ | |
321 | itn = net_generic(net, ipgre_net_id); | |
322 | res = __ipgre_rcv(skb, tpi, itn, hdr_len, true); | |
323 | } | |
324 | return res; | |
325 | } | |
326 | ||
327 | static int gre_rcv(struct sk_buff *skb) | |
328 | { | |
329 | struct tnl_ptk_info tpi; | |
330 | bool csum_err = false; | |
331 | int hdr_len; | |
332 | ||
333 | #ifdef CONFIG_NET_IPGRE_BROADCAST | |
334 | if (ipv4_is_multicast(ip_hdr(skb)->daddr)) { | |
335 | /* Looped back packet, drop it! */ | |
336 | if (rt_is_output_route(skb_rtable(skb))) | |
337 | goto drop; | |
338 | } | |
339 | #endif | |
340 | ||
341 | hdr_len = gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IP)); | |
342 | if (hdr_len < 0) | |
343 | goto drop; | |
344 | ||
345 | if (ipgre_rcv(skb, &tpi, hdr_len) == PACKET_RCVD) | |
346 | return 0; | |
347 | ||
348 | icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0); | |
349 | drop: | |
350 | kfree_skb(skb); | |
351 | return 0; | |
352 | } | |
353 | ||
354 | static void __gre_xmit(struct sk_buff *skb, struct net_device *dev, | |
355 | const struct iphdr *tnl_params, | |
356 | __be16 proto) | |
357 | { | |
358 | struct ip_tunnel *tunnel = netdev_priv(dev); | |
359 | ||
360 | if (tunnel->parms.o_flags & TUNNEL_SEQ) | |
361 | tunnel->o_seqno++; | |
362 | ||
363 | /* Push GRE header. */ | |
364 | gre_build_header(skb, tunnel->tun_hlen, | |
365 | tunnel->parms.o_flags, proto, tunnel->parms.o_key, | |
366 | htonl(tunnel->o_seqno)); | |
367 | ||
368 | skb_set_inner_protocol(skb, proto); | |
369 | ip_tunnel_xmit(skb, dev, tnl_params, tnl_params->protocol); | |
370 | } | |
371 | ||
372 | static int gre_handle_offloads(struct sk_buff *skb, bool csum) | |
373 | { | |
374 | return iptunnel_handle_offloads(skb, csum ? SKB_GSO_GRE_CSUM : SKB_GSO_GRE); | |
375 | } | |
376 | ||
377 | static struct rtable *gre_get_rt(struct sk_buff *skb, | |
378 | struct net_device *dev, | |
379 | struct flowi4 *fl, | |
380 | const struct ip_tunnel_key *key) | |
381 | { | |
382 | struct net *net = dev_net(dev); | |
383 | ||
384 | memset(fl, 0, sizeof(*fl)); | |
385 | fl->daddr = key->u.ipv4.dst; | |
386 | fl->saddr = key->u.ipv4.src; | |
387 | fl->flowi4_tos = RT_TOS(key->tos); | |
388 | fl->flowi4_mark = skb->mark; | |
389 | fl->flowi4_proto = IPPROTO_GRE; | |
390 | ||
391 | return ip_route_output_key(net, fl); | |
392 | } | |
393 | ||
394 | static void gre_fb_xmit(struct sk_buff *skb, struct net_device *dev, | |
395 | __be16 proto) | |
396 | { | |
397 | struct ip_tunnel_info *tun_info; | |
398 | const struct ip_tunnel_key *key; | |
399 | struct rtable *rt = NULL; | |
400 | struct flowi4 fl; | |
401 | int min_headroom; | |
402 | int tunnel_hlen; | |
403 | __be16 df, flags; | |
404 | bool use_cache; | |
405 | int err; | |
406 | ||
407 | tun_info = skb_tunnel_info(skb); | |
408 | if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) || | |
409 | ip_tunnel_info_af(tun_info) != AF_INET)) | |
410 | goto err_free_skb; | |
411 | ||
412 | key = &tun_info->key; | |
413 | use_cache = ip_tunnel_dst_cache_usable(skb, tun_info); | |
414 | if (use_cache) | |
415 | rt = dst_cache_get_ip4(&tun_info->dst_cache, &fl.saddr); | |
416 | if (!rt) { | |
417 | rt = gre_get_rt(skb, dev, &fl, key); | |
418 | if (IS_ERR(rt)) | |
419 | goto err_free_skb; | |
420 | if (use_cache) | |
421 | dst_cache_set_ip4(&tun_info->dst_cache, &rt->dst, | |
422 | fl.saddr); | |
423 | } | |
424 | ||
425 | tunnel_hlen = gre_calc_hlen(key->tun_flags); | |
426 | ||
427 | min_headroom = LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len | |
428 | + tunnel_hlen + sizeof(struct iphdr); | |
429 | if (skb_headroom(skb) < min_headroom || skb_header_cloned(skb)) { | |
430 | int head_delta = SKB_DATA_ALIGN(min_headroom - | |
431 | skb_headroom(skb) + | |
432 | 16); | |
433 | err = pskb_expand_head(skb, max_t(int, head_delta, 0), | |
434 | 0, GFP_ATOMIC); | |
435 | if (unlikely(err)) | |
436 | goto err_free_rt; | |
437 | } | |
438 | ||
439 | /* Push Tunnel header. */ | |
440 | if (gre_handle_offloads(skb, !!(tun_info->key.tun_flags & TUNNEL_CSUM))) | |
441 | goto err_free_rt; | |
442 | ||
443 | flags = tun_info->key.tun_flags & (TUNNEL_CSUM | TUNNEL_KEY); | |
444 | gre_build_header(skb, tunnel_hlen, flags, proto, | |
445 | tunnel_id_to_key(tun_info->key.tun_id), 0); | |
446 | ||
447 | df = key->tun_flags & TUNNEL_DONT_FRAGMENT ? htons(IP_DF) : 0; | |
448 | ||
449 | iptunnel_xmit(skb->sk, rt, skb, fl.saddr, key->u.ipv4.dst, IPPROTO_GRE, | |
450 | key->tos, key->ttl, df, false); | |
451 | return; | |
452 | ||
453 | err_free_rt: | |
454 | ip_rt_put(rt); | |
455 | err_free_skb: | |
456 | kfree_skb(skb); | |
457 | dev->stats.tx_dropped++; | |
458 | } | |
459 | ||
460 | static int gre_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb) | |
461 | { | |
462 | struct ip_tunnel_info *info = skb_tunnel_info(skb); | |
463 | struct rtable *rt; | |
464 | struct flowi4 fl4; | |
465 | ||
466 | if (ip_tunnel_info_af(info) != AF_INET) | |
467 | return -EINVAL; | |
468 | ||
469 | rt = gre_get_rt(skb, dev, &fl4, &info->key); | |
470 | if (IS_ERR(rt)) | |
471 | return PTR_ERR(rt); | |
472 | ||
473 | ip_rt_put(rt); | |
474 | info->key.u.ipv4.src = fl4.saddr; | |
475 | return 0; | |
476 | } | |
477 | ||
478 | static netdev_tx_t ipgre_xmit(struct sk_buff *skb, | |
479 | struct net_device *dev) | |
480 | { | |
481 | struct ip_tunnel *tunnel = netdev_priv(dev); | |
482 | const struct iphdr *tnl_params; | |
483 | ||
484 | if (tunnel->collect_md) { | |
485 | gre_fb_xmit(skb, dev, skb->protocol); | |
486 | return NETDEV_TX_OK; | |
487 | } | |
488 | ||
489 | if (dev->header_ops) { | |
490 | /* Need space for new headers */ | |
491 | if (skb_cow_head(skb, dev->needed_headroom - | |
492 | (tunnel->hlen + sizeof(struct iphdr)))) | |
493 | goto free_skb; | |
494 | ||
495 | tnl_params = (const struct iphdr *)skb->data; | |
496 | ||
497 | /* Pull skb since ip_tunnel_xmit() needs skb->data pointing | |
498 | * to gre header. | |
499 | */ | |
500 | skb_pull(skb, tunnel->hlen + sizeof(struct iphdr)); | |
501 | skb_reset_mac_header(skb); | |
502 | } else { | |
503 | if (skb_cow_head(skb, dev->needed_headroom)) | |
504 | goto free_skb; | |
505 | ||
506 | tnl_params = &tunnel->parms.iph; | |
507 | } | |
508 | ||
509 | if (gre_handle_offloads(skb, !!(tunnel->parms.o_flags & TUNNEL_CSUM))) | |
510 | goto free_skb; | |
511 | ||
512 | __gre_xmit(skb, dev, tnl_params, skb->protocol); | |
513 | return NETDEV_TX_OK; | |
514 | ||
515 | free_skb: | |
516 | kfree_skb(skb); | |
517 | dev->stats.tx_dropped++; | |
518 | return NETDEV_TX_OK; | |
519 | } | |
520 | ||
521 | static netdev_tx_t gre_tap_xmit(struct sk_buff *skb, | |
522 | struct net_device *dev) | |
523 | { | |
524 | struct ip_tunnel *tunnel = netdev_priv(dev); | |
525 | ||
526 | if (tunnel->collect_md) { | |
527 | gre_fb_xmit(skb, dev, htons(ETH_P_TEB)); | |
528 | return NETDEV_TX_OK; | |
529 | } | |
530 | ||
531 | if (gre_handle_offloads(skb, !!(tunnel->parms.o_flags & TUNNEL_CSUM))) | |
532 | goto free_skb; | |
533 | ||
534 | if (skb_cow_head(skb, dev->needed_headroom)) | |
535 | goto free_skb; | |
536 | ||
537 | __gre_xmit(skb, dev, &tunnel->parms.iph, htons(ETH_P_TEB)); | |
538 | return NETDEV_TX_OK; | |
539 | ||
540 | free_skb: | |
541 | kfree_skb(skb); | |
542 | dev->stats.tx_dropped++; | |
543 | return NETDEV_TX_OK; | |
544 | } | |
545 | ||
546 | static int ipgre_tunnel_ioctl(struct net_device *dev, | |
547 | struct ifreq *ifr, int cmd) | |
548 | { | |
549 | int err; | |
550 | struct ip_tunnel_parm p; | |
551 | ||
552 | if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) | |
553 | return -EFAULT; | |
554 | if (cmd == SIOCADDTUNNEL || cmd == SIOCCHGTUNNEL) { | |
555 | if (p.iph.version != 4 || p.iph.protocol != IPPROTO_GRE || | |
556 | p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF)) || | |
557 | ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING))) | |
558 | return -EINVAL; | |
559 | } | |
560 | p.i_flags = gre_flags_to_tnl_flags(p.i_flags); | |
561 | p.o_flags = gre_flags_to_tnl_flags(p.o_flags); | |
562 | ||
563 | err = ip_tunnel_ioctl(dev, &p, cmd); | |
564 | if (err) | |
565 | return err; | |
566 | ||
567 | p.i_flags = gre_tnl_flags_to_gre_flags(p.i_flags); | |
568 | p.o_flags = gre_tnl_flags_to_gre_flags(p.o_flags); | |
569 | ||
570 | if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) | |
571 | return -EFAULT; | |
572 | return 0; | |
573 | } | |
574 | ||
575 | /* Nice toy. Unfortunately, useless in real life :-) | |
576 | It allows to construct virtual multiprotocol broadcast "LAN" | |
577 | over the Internet, provided multicast routing is tuned. | |
578 | ||
579 | ||
580 | I have no idea was this bicycle invented before me, | |
581 | so that I had to set ARPHRD_IPGRE to a random value. | |
582 | I have an impression, that Cisco could make something similar, | |
583 | but this feature is apparently missing in IOS<=11.2(8). | |
584 | ||
585 | I set up 10.66.66/24 and fec0:6666:6666::0/96 as virtual networks | |
586 | with broadcast 224.66.66.66. If you have access to mbone, play with me :-) | |
587 | ||
588 | ping -t 255 224.66.66.66 | |
589 | ||
590 | If nobody answers, mbone does not work. | |
591 | ||
592 | ip tunnel add Universe mode gre remote 224.66.66.66 local <Your_real_addr> ttl 255 | |
593 | ip addr add 10.66.66.<somewhat>/24 dev Universe | |
594 | ifconfig Universe up | |
595 | ifconfig Universe add fe80::<Your_real_addr>/10 | |
596 | ifconfig Universe add fec0:6666:6666::<Your_real_addr>/96 | |
597 | ftp 10.66.66.66 | |
598 | ... | |
599 | ftp fec0:6666:6666::193.233.7.65 | |
600 | ... | |
601 | */ | |
602 | static int ipgre_header(struct sk_buff *skb, struct net_device *dev, | |
603 | unsigned short type, | |
604 | const void *daddr, const void *saddr, unsigned int len) | |
605 | { | |
606 | struct ip_tunnel *t = netdev_priv(dev); | |
607 | struct iphdr *iph; | |
608 | struct gre_base_hdr *greh; | |
609 | ||
610 | iph = (struct iphdr *)skb_push(skb, t->hlen + sizeof(*iph)); | |
611 | greh = (struct gre_base_hdr *)(iph+1); | |
612 | greh->flags = gre_tnl_flags_to_gre_flags(t->parms.o_flags); | |
613 | greh->protocol = htons(type); | |
614 | ||
615 | memcpy(iph, &t->parms.iph, sizeof(struct iphdr)); | |
616 | ||
617 | /* Set the source hardware address. */ | |
618 | if (saddr) | |
619 | memcpy(&iph->saddr, saddr, 4); | |
620 | if (daddr) | |
621 | memcpy(&iph->daddr, daddr, 4); | |
622 | if (iph->daddr) | |
623 | return t->hlen + sizeof(*iph); | |
624 | ||
625 | return -(t->hlen + sizeof(*iph)); | |
626 | } | |
627 | ||
628 | static int ipgre_header_parse(const struct sk_buff *skb, unsigned char *haddr) | |
629 | { | |
630 | const struct iphdr *iph = (const struct iphdr *) skb_mac_header(skb); | |
631 | memcpy(haddr, &iph->saddr, 4); | |
632 | return 4; | |
633 | } | |
634 | ||
635 | static const struct header_ops ipgre_header_ops = { | |
636 | .create = ipgre_header, | |
637 | .parse = ipgre_header_parse, | |
638 | }; | |
639 | ||
640 | #ifdef CONFIG_NET_IPGRE_BROADCAST | |
641 | static int ipgre_open(struct net_device *dev) | |
642 | { | |
643 | struct ip_tunnel *t = netdev_priv(dev); | |
644 | ||
645 | if (ipv4_is_multicast(t->parms.iph.daddr)) { | |
646 | struct flowi4 fl4; | |
647 | struct rtable *rt; | |
648 | ||
649 | rt = ip_route_output_gre(t->net, &fl4, | |
650 | t->parms.iph.daddr, | |
651 | t->parms.iph.saddr, | |
652 | t->parms.o_key, | |
653 | RT_TOS(t->parms.iph.tos), | |
654 | t->parms.link); | |
655 | if (IS_ERR(rt)) | |
656 | return -EADDRNOTAVAIL; | |
657 | dev = rt->dst.dev; | |
658 | ip_rt_put(rt); | |
659 | if (!__in_dev_get_rtnl(dev)) | |
660 | return -EADDRNOTAVAIL; | |
661 | t->mlink = dev->ifindex; | |
662 | ip_mc_inc_group(__in_dev_get_rtnl(dev), t->parms.iph.daddr); | |
663 | } | |
664 | return 0; | |
665 | } | |
666 | ||
667 | static int ipgre_close(struct net_device *dev) | |
668 | { | |
669 | struct ip_tunnel *t = netdev_priv(dev); | |
670 | ||
671 | if (ipv4_is_multicast(t->parms.iph.daddr) && t->mlink) { | |
672 | struct in_device *in_dev; | |
673 | in_dev = inetdev_by_index(t->net, t->mlink); | |
674 | if (in_dev) | |
675 | ip_mc_dec_group(in_dev, t->parms.iph.daddr); | |
676 | } | |
677 | return 0; | |
678 | } | |
679 | #endif | |
680 | ||
681 | static const struct net_device_ops ipgre_netdev_ops = { | |
682 | .ndo_init = ipgre_tunnel_init, | |
683 | .ndo_uninit = ip_tunnel_uninit, | |
684 | #ifdef CONFIG_NET_IPGRE_BROADCAST | |
685 | .ndo_open = ipgre_open, | |
686 | .ndo_stop = ipgre_close, | |
687 | #endif | |
688 | .ndo_start_xmit = ipgre_xmit, | |
689 | .ndo_do_ioctl = ipgre_tunnel_ioctl, | |
690 | .ndo_change_mtu = ip_tunnel_change_mtu, | |
691 | .ndo_get_stats64 = ip_tunnel_get_stats64, | |
692 | .ndo_get_iflink = ip_tunnel_get_iflink, | |
693 | }; | |
694 | ||
695 | #define GRE_FEATURES (NETIF_F_SG | \ | |
696 | NETIF_F_FRAGLIST | \ | |
697 | NETIF_F_HIGHDMA | \ | |
698 | NETIF_F_HW_CSUM) | |
699 | ||
700 | static void ipgre_tunnel_setup(struct net_device *dev) | |
701 | { | |
702 | dev->netdev_ops = &ipgre_netdev_ops; | |
703 | dev->type = ARPHRD_IPGRE; | |
704 | ip_tunnel_setup(dev, ipgre_net_id); | |
705 | } | |
706 | ||
707 | static void __gre_tunnel_init(struct net_device *dev) | |
708 | { | |
709 | struct ip_tunnel *tunnel; | |
710 | int t_hlen; | |
711 | ||
712 | tunnel = netdev_priv(dev); | |
713 | tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags); | |
714 | tunnel->parms.iph.protocol = IPPROTO_GRE; | |
715 | ||
716 | tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen; | |
717 | ||
718 | t_hlen = tunnel->hlen + sizeof(struct iphdr); | |
719 | ||
720 | dev->needed_headroom = LL_MAX_HEADER + t_hlen + 4; | |
721 | dev->mtu = ETH_DATA_LEN - t_hlen - 4; | |
722 | ||
723 | dev->features |= GRE_FEATURES; | |
724 | dev->hw_features |= GRE_FEATURES; | |
725 | ||
726 | if (!(tunnel->parms.o_flags & TUNNEL_SEQ)) { | |
727 | /* TCP offload with GRE SEQ is not supported, nor | |
728 | * can we support 2 levels of outer headers requiring | |
729 | * an update. | |
730 | */ | |
731 | if (!(tunnel->parms.o_flags & TUNNEL_CSUM) || | |
732 | (tunnel->encap.type == TUNNEL_ENCAP_NONE)) { | |
733 | dev->features |= NETIF_F_GSO_SOFTWARE; | |
734 | dev->hw_features |= NETIF_F_GSO_SOFTWARE; | |
735 | } | |
736 | ||
737 | /* Can use a lockless transmit, unless we generate | |
738 | * output sequences | |
739 | */ | |
740 | dev->features |= NETIF_F_LLTX; | |
741 | } | |
742 | } | |
743 | ||
744 | static int ipgre_tunnel_init(struct net_device *dev) | |
745 | { | |
746 | struct ip_tunnel *tunnel = netdev_priv(dev); | |
747 | struct iphdr *iph = &tunnel->parms.iph; | |
748 | ||
749 | __gre_tunnel_init(dev); | |
750 | ||
751 | memcpy(dev->dev_addr, &iph->saddr, 4); | |
752 | memcpy(dev->broadcast, &iph->daddr, 4); | |
753 | ||
754 | dev->flags = IFF_NOARP; | |
755 | netif_keep_dst(dev); | |
756 | dev->addr_len = 4; | |
757 | ||
758 | if (iph->daddr && !tunnel->collect_md) { | |
759 | #ifdef CONFIG_NET_IPGRE_BROADCAST | |
760 | if (ipv4_is_multicast(iph->daddr)) { | |
761 | if (!iph->saddr) | |
762 | return -EINVAL; | |
763 | dev->flags = IFF_BROADCAST; | |
764 | dev->header_ops = &ipgre_header_ops; | |
765 | } | |
766 | #endif | |
767 | } else if (!tunnel->collect_md) { | |
768 | dev->header_ops = &ipgre_header_ops; | |
769 | } | |
770 | ||
771 | return ip_tunnel_init(dev); | |
772 | } | |
773 | ||
774 | static const struct gre_protocol ipgre_protocol = { | |
775 | .handler = gre_rcv, | |
776 | .err_handler = gre_err, | |
777 | }; | |
778 | ||
779 | static int __net_init ipgre_init_net(struct net *net) | |
780 | { | |
781 | return ip_tunnel_init_net(net, ipgre_net_id, &ipgre_link_ops, NULL); | |
782 | } | |
783 | ||
784 | static void __net_exit ipgre_exit_net(struct net *net) | |
785 | { | |
786 | struct ip_tunnel_net *itn = net_generic(net, ipgre_net_id); | |
787 | ip_tunnel_delete_net(itn, &ipgre_link_ops); | |
788 | } | |
789 | ||
790 | static struct pernet_operations ipgre_net_ops = { | |
791 | .init = ipgre_init_net, | |
792 | .exit = ipgre_exit_net, | |
793 | .id = &ipgre_net_id, | |
794 | .size = sizeof(struct ip_tunnel_net), | |
795 | }; | |
796 | ||
797 | static int ipgre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[]) | |
798 | { | |
799 | __be16 flags; | |
800 | ||
801 | if (!data) | |
802 | return 0; | |
803 | ||
804 | flags = 0; | |
805 | if (data[IFLA_GRE_IFLAGS]) | |
806 | flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]); | |
807 | if (data[IFLA_GRE_OFLAGS]) | |
808 | flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]); | |
809 | if (flags & (GRE_VERSION|GRE_ROUTING)) | |
810 | return -EINVAL; | |
811 | ||
812 | if (data[IFLA_GRE_COLLECT_METADATA] && | |
813 | data[IFLA_GRE_ENCAP_TYPE] && | |
814 | nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]) != TUNNEL_ENCAP_NONE) | |
815 | return -EINVAL; | |
816 | ||
817 | return 0; | |
818 | } | |
819 | ||
820 | static int ipgre_tap_validate(struct nlattr *tb[], struct nlattr *data[]) | |
821 | { | |
822 | __be32 daddr; | |
823 | ||
824 | if (tb[IFLA_ADDRESS]) { | |
825 | if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) | |
826 | return -EINVAL; | |
827 | if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) | |
828 | return -EADDRNOTAVAIL; | |
829 | } | |
830 | ||
831 | if (!data) | |
832 | goto out; | |
833 | ||
834 | if (data[IFLA_GRE_REMOTE]) { | |
835 | memcpy(&daddr, nla_data(data[IFLA_GRE_REMOTE]), 4); | |
836 | if (!daddr) | |
837 | return -EINVAL; | |
838 | } | |
839 | ||
840 | out: | |
841 | return ipgre_tunnel_validate(tb, data); | |
842 | } | |
843 | ||
844 | static void ipgre_netlink_parms(struct net_device *dev, | |
845 | struct nlattr *data[], | |
846 | struct nlattr *tb[], | |
847 | struct ip_tunnel_parm *parms) | |
848 | { | |
849 | memset(parms, 0, sizeof(*parms)); | |
850 | ||
851 | parms->iph.protocol = IPPROTO_GRE; | |
852 | ||
853 | if (!data) | |
854 | return; | |
855 | ||
856 | if (data[IFLA_GRE_LINK]) | |
857 | parms->link = nla_get_u32(data[IFLA_GRE_LINK]); | |
858 | ||
859 | if (data[IFLA_GRE_IFLAGS]) | |
860 | parms->i_flags = gre_flags_to_tnl_flags(nla_get_be16(data[IFLA_GRE_IFLAGS])); | |
861 | ||
862 | if (data[IFLA_GRE_OFLAGS]) | |
863 | parms->o_flags = gre_flags_to_tnl_flags(nla_get_be16(data[IFLA_GRE_OFLAGS])); | |
864 | ||
865 | if (data[IFLA_GRE_IKEY]) | |
866 | parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]); | |
867 | ||
868 | if (data[IFLA_GRE_OKEY]) | |
869 | parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]); | |
870 | ||
871 | if (data[IFLA_GRE_LOCAL]) | |
872 | parms->iph.saddr = nla_get_in_addr(data[IFLA_GRE_LOCAL]); | |
873 | ||
874 | if (data[IFLA_GRE_REMOTE]) | |
875 | parms->iph.daddr = nla_get_in_addr(data[IFLA_GRE_REMOTE]); | |
876 | ||
877 | if (data[IFLA_GRE_TTL]) | |
878 | parms->iph.ttl = nla_get_u8(data[IFLA_GRE_TTL]); | |
879 | ||
880 | if (data[IFLA_GRE_TOS]) | |
881 | parms->iph.tos = nla_get_u8(data[IFLA_GRE_TOS]); | |
882 | ||
883 | if (!data[IFLA_GRE_PMTUDISC] || nla_get_u8(data[IFLA_GRE_PMTUDISC])) | |
884 | parms->iph.frag_off = htons(IP_DF); | |
885 | ||
886 | if (data[IFLA_GRE_COLLECT_METADATA]) { | |
887 | struct ip_tunnel *t = netdev_priv(dev); | |
888 | ||
889 | t->collect_md = true; | |
890 | if (dev->type == ARPHRD_IPGRE) | |
891 | dev->type = ARPHRD_NONE; | |
892 | } | |
893 | } | |
894 | ||
895 | /* This function returns true when ENCAP attributes are present in the nl msg */ | |
896 | static bool ipgre_netlink_encap_parms(struct nlattr *data[], | |
897 | struct ip_tunnel_encap *ipencap) | |
898 | { | |
899 | bool ret = false; | |
900 | ||
901 | memset(ipencap, 0, sizeof(*ipencap)); | |
902 | ||
903 | if (!data) | |
904 | return ret; | |
905 | ||
906 | if (data[IFLA_GRE_ENCAP_TYPE]) { | |
907 | ret = true; | |
908 | ipencap->type = nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]); | |
909 | } | |
910 | ||
911 | if (data[IFLA_GRE_ENCAP_FLAGS]) { | |
912 | ret = true; | |
913 | ipencap->flags = nla_get_u16(data[IFLA_GRE_ENCAP_FLAGS]); | |
914 | } | |
915 | ||
916 | if (data[IFLA_GRE_ENCAP_SPORT]) { | |
917 | ret = true; | |
918 | ipencap->sport = nla_get_be16(data[IFLA_GRE_ENCAP_SPORT]); | |
919 | } | |
920 | ||
921 | if (data[IFLA_GRE_ENCAP_DPORT]) { | |
922 | ret = true; | |
923 | ipencap->dport = nla_get_be16(data[IFLA_GRE_ENCAP_DPORT]); | |
924 | } | |
925 | ||
926 | return ret; | |
927 | } | |
928 | ||
929 | static int gre_tap_init(struct net_device *dev) | |
930 | { | |
931 | __gre_tunnel_init(dev); | |
932 | dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; | |
933 | ||
934 | return ip_tunnel_init(dev); | |
935 | } | |
936 | ||
937 | static const struct net_device_ops gre_tap_netdev_ops = { | |
938 | .ndo_init = gre_tap_init, | |
939 | .ndo_uninit = ip_tunnel_uninit, | |
940 | .ndo_start_xmit = gre_tap_xmit, | |
941 | .ndo_set_mac_address = eth_mac_addr, | |
942 | .ndo_validate_addr = eth_validate_addr, | |
943 | .ndo_change_mtu = ip_tunnel_change_mtu, | |
944 | .ndo_get_stats64 = ip_tunnel_get_stats64, | |
945 | .ndo_get_iflink = ip_tunnel_get_iflink, | |
946 | .ndo_fill_metadata_dst = gre_fill_metadata_dst, | |
947 | }; | |
948 | ||
949 | static void ipgre_tap_setup(struct net_device *dev) | |
950 | { | |
951 | ether_setup(dev); | |
952 | dev->netdev_ops = &gre_tap_netdev_ops; | |
953 | dev->priv_flags &= ~IFF_TX_SKB_SHARING; | |
954 | dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; | |
955 | ip_tunnel_setup(dev, gre_tap_net_id); | |
956 | } | |
957 | ||
958 | static int ipgre_newlink(struct net *src_net, struct net_device *dev, | |
959 | struct nlattr *tb[], struct nlattr *data[]) | |
960 | { | |
961 | struct ip_tunnel_parm p; | |
962 | struct ip_tunnel_encap ipencap; | |
963 | ||
964 | if (ipgre_netlink_encap_parms(data, &ipencap)) { | |
965 | struct ip_tunnel *t = netdev_priv(dev); | |
966 | int err = ip_tunnel_encap_setup(t, &ipencap); | |
967 | ||
968 | if (err < 0) | |
969 | return err; | |
970 | } | |
971 | ||
972 | ipgre_netlink_parms(dev, data, tb, &p); | |
973 | return ip_tunnel_newlink(dev, tb, &p); | |
974 | } | |
975 | ||
976 | static int ipgre_changelink(struct net_device *dev, struct nlattr *tb[], | |
977 | struct nlattr *data[]) | |
978 | { | |
979 | struct ip_tunnel_parm p; | |
980 | struct ip_tunnel_encap ipencap; | |
981 | ||
982 | if (ipgre_netlink_encap_parms(data, &ipencap)) { | |
983 | struct ip_tunnel *t = netdev_priv(dev); | |
984 | int err = ip_tunnel_encap_setup(t, &ipencap); | |
985 | ||
986 | if (err < 0) | |
987 | return err; | |
988 | } | |
989 | ||
990 | ipgre_netlink_parms(dev, data, tb, &p); | |
991 | return ip_tunnel_changelink(dev, tb, &p); | |
992 | } | |
993 | ||
994 | static size_t ipgre_get_size(const struct net_device *dev) | |
995 | { | |
996 | return | |
997 | /* IFLA_GRE_LINK */ | |
998 | nla_total_size(4) + | |
999 | /* IFLA_GRE_IFLAGS */ | |
1000 | nla_total_size(2) + | |
1001 | /* IFLA_GRE_OFLAGS */ | |
1002 | nla_total_size(2) + | |
1003 | /* IFLA_GRE_IKEY */ | |
1004 | nla_total_size(4) + | |
1005 | /* IFLA_GRE_OKEY */ | |
1006 | nla_total_size(4) + | |
1007 | /* IFLA_GRE_LOCAL */ | |
1008 | nla_total_size(4) + | |
1009 | /* IFLA_GRE_REMOTE */ | |
1010 | nla_total_size(4) + | |
1011 | /* IFLA_GRE_TTL */ | |
1012 | nla_total_size(1) + | |
1013 | /* IFLA_GRE_TOS */ | |
1014 | nla_total_size(1) + | |
1015 | /* IFLA_GRE_PMTUDISC */ | |
1016 | nla_total_size(1) + | |
1017 | /* IFLA_GRE_ENCAP_TYPE */ | |
1018 | nla_total_size(2) + | |
1019 | /* IFLA_GRE_ENCAP_FLAGS */ | |
1020 | nla_total_size(2) + | |
1021 | /* IFLA_GRE_ENCAP_SPORT */ | |
1022 | nla_total_size(2) + | |
1023 | /* IFLA_GRE_ENCAP_DPORT */ | |
1024 | nla_total_size(2) + | |
1025 | /* IFLA_GRE_COLLECT_METADATA */ | |
1026 | nla_total_size(0) + | |
1027 | 0; | |
1028 | } | |
1029 | ||
1030 | static int ipgre_fill_info(struct sk_buff *skb, const struct net_device *dev) | |
1031 | { | |
1032 | struct ip_tunnel *t = netdev_priv(dev); | |
1033 | struct ip_tunnel_parm *p = &t->parms; | |
1034 | ||
1035 | if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) || | |
1036 | nla_put_be16(skb, IFLA_GRE_IFLAGS, | |
1037 | gre_tnl_flags_to_gre_flags(p->i_flags)) || | |
1038 | nla_put_be16(skb, IFLA_GRE_OFLAGS, | |
1039 | gre_tnl_flags_to_gre_flags(p->o_flags)) || | |
1040 | nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) || | |
1041 | nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) || | |
1042 | nla_put_in_addr(skb, IFLA_GRE_LOCAL, p->iph.saddr) || | |
1043 | nla_put_in_addr(skb, IFLA_GRE_REMOTE, p->iph.daddr) || | |
1044 | nla_put_u8(skb, IFLA_GRE_TTL, p->iph.ttl) || | |
1045 | nla_put_u8(skb, IFLA_GRE_TOS, p->iph.tos) || | |
1046 | nla_put_u8(skb, IFLA_GRE_PMTUDISC, | |
1047 | !!(p->iph.frag_off & htons(IP_DF)))) | |
1048 | goto nla_put_failure; | |
1049 | ||
1050 | if (nla_put_u16(skb, IFLA_GRE_ENCAP_TYPE, | |
1051 | t->encap.type) || | |
1052 | nla_put_be16(skb, IFLA_GRE_ENCAP_SPORT, | |
1053 | t->encap.sport) || | |
1054 | nla_put_be16(skb, IFLA_GRE_ENCAP_DPORT, | |
1055 | t->encap.dport) || | |
1056 | nla_put_u16(skb, IFLA_GRE_ENCAP_FLAGS, | |
1057 | t->encap.flags)) | |
1058 | goto nla_put_failure; | |
1059 | ||
1060 | if (t->collect_md) { | |
1061 | if (nla_put_flag(skb, IFLA_GRE_COLLECT_METADATA)) | |
1062 | goto nla_put_failure; | |
1063 | } | |
1064 | ||
1065 | return 0; | |
1066 | ||
1067 | nla_put_failure: | |
1068 | return -EMSGSIZE; | |
1069 | } | |
1070 | ||
1071 | static const struct nla_policy ipgre_policy[IFLA_GRE_MAX + 1] = { | |
1072 | [IFLA_GRE_LINK] = { .type = NLA_U32 }, | |
1073 | [IFLA_GRE_IFLAGS] = { .type = NLA_U16 }, | |
1074 | [IFLA_GRE_OFLAGS] = { .type = NLA_U16 }, | |
1075 | [IFLA_GRE_IKEY] = { .type = NLA_U32 }, | |
1076 | [IFLA_GRE_OKEY] = { .type = NLA_U32 }, | |
1077 | [IFLA_GRE_LOCAL] = { .len = FIELD_SIZEOF(struct iphdr, saddr) }, | |
1078 | [IFLA_GRE_REMOTE] = { .len = FIELD_SIZEOF(struct iphdr, daddr) }, | |
1079 | [IFLA_GRE_TTL] = { .type = NLA_U8 }, | |
1080 | [IFLA_GRE_TOS] = { .type = NLA_U8 }, | |
1081 | [IFLA_GRE_PMTUDISC] = { .type = NLA_U8 }, | |
1082 | [IFLA_GRE_ENCAP_TYPE] = { .type = NLA_U16 }, | |
1083 | [IFLA_GRE_ENCAP_FLAGS] = { .type = NLA_U16 }, | |
1084 | [IFLA_GRE_ENCAP_SPORT] = { .type = NLA_U16 }, | |
1085 | [IFLA_GRE_ENCAP_DPORT] = { .type = NLA_U16 }, | |
1086 | [IFLA_GRE_COLLECT_METADATA] = { .type = NLA_FLAG }, | |
1087 | }; | |
1088 | ||
1089 | static struct rtnl_link_ops ipgre_link_ops __read_mostly = { | |
1090 | .kind = "gre", | |
1091 | .maxtype = IFLA_GRE_MAX, | |
1092 | .policy = ipgre_policy, | |
1093 | .priv_size = sizeof(struct ip_tunnel), | |
1094 | .setup = ipgre_tunnel_setup, | |
1095 | .validate = ipgre_tunnel_validate, | |
1096 | .newlink = ipgre_newlink, | |
1097 | .changelink = ipgre_changelink, | |
1098 | .dellink = ip_tunnel_dellink, | |
1099 | .get_size = ipgre_get_size, | |
1100 | .fill_info = ipgre_fill_info, | |
1101 | .get_link_net = ip_tunnel_get_link_net, | |
1102 | }; | |
1103 | ||
1104 | static struct rtnl_link_ops ipgre_tap_ops __read_mostly = { | |
1105 | .kind = "gretap", | |
1106 | .maxtype = IFLA_GRE_MAX, | |
1107 | .policy = ipgre_policy, | |
1108 | .priv_size = sizeof(struct ip_tunnel), | |
1109 | .setup = ipgre_tap_setup, | |
1110 | .validate = ipgre_tap_validate, | |
1111 | .newlink = ipgre_newlink, | |
1112 | .changelink = ipgre_changelink, | |
1113 | .dellink = ip_tunnel_dellink, | |
1114 | .get_size = ipgre_get_size, | |
1115 | .fill_info = ipgre_fill_info, | |
1116 | .get_link_net = ip_tunnel_get_link_net, | |
1117 | }; | |
1118 | ||
1119 | struct net_device *gretap_fb_dev_create(struct net *net, const char *name, | |
1120 | u8 name_assign_type) | |
1121 | { | |
1122 | struct nlattr *tb[IFLA_MAX + 1]; | |
1123 | struct net_device *dev; | |
1124 | LIST_HEAD(list_kill); | |
1125 | struct ip_tunnel *t; | |
1126 | int err; | |
1127 | ||
1128 | memset(&tb, 0, sizeof(tb)); | |
1129 | ||
1130 | dev = rtnl_create_link(net, name, name_assign_type, | |
1131 | &ipgre_tap_ops, tb); | |
1132 | if (IS_ERR(dev)) | |
1133 | return dev; | |
1134 | ||
1135 | /* Configure flow based GRE device. */ | |
1136 | t = netdev_priv(dev); | |
1137 | t->collect_md = true; | |
1138 | ||
1139 | err = ipgre_newlink(net, dev, tb, NULL); | |
1140 | if (err < 0) { | |
1141 | free_netdev(dev); | |
1142 | return ERR_PTR(err); | |
1143 | } | |
1144 | ||
1145 | /* openvswitch users expect packet sizes to be unrestricted, | |
1146 | * so set the largest MTU we can. | |
1147 | */ | |
1148 | err = __ip_tunnel_change_mtu(dev, IP_MAX_MTU, false); | |
1149 | if (err) | |
1150 | goto out; | |
1151 | ||
1152 | err = rtnl_configure_link(dev, NULL); | |
1153 | if (err < 0) | |
1154 | goto out; | |
1155 | ||
1156 | return dev; | |
1157 | out: | |
1158 | ip_tunnel_dellink(dev, &list_kill); | |
1159 | unregister_netdevice_many(&list_kill); | |
1160 | return ERR_PTR(err); | |
1161 | } | |
1162 | EXPORT_SYMBOL_GPL(gretap_fb_dev_create); | |
1163 | ||
1164 | static int __net_init ipgre_tap_init_net(struct net *net) | |
1165 | { | |
1166 | return ip_tunnel_init_net(net, gre_tap_net_id, &ipgre_tap_ops, "gretap0"); | |
1167 | } | |
1168 | ||
1169 | static void __net_exit ipgre_tap_exit_net(struct net *net) | |
1170 | { | |
1171 | struct ip_tunnel_net *itn = net_generic(net, gre_tap_net_id); | |
1172 | ip_tunnel_delete_net(itn, &ipgre_tap_ops); | |
1173 | } | |
1174 | ||
1175 | static struct pernet_operations ipgre_tap_net_ops = { | |
1176 | .init = ipgre_tap_init_net, | |
1177 | .exit = ipgre_tap_exit_net, | |
1178 | .id = &gre_tap_net_id, | |
1179 | .size = sizeof(struct ip_tunnel_net), | |
1180 | }; | |
1181 | ||
1182 | static int __init ipgre_init(void) | |
1183 | { | |
1184 | int err; | |
1185 | ||
1186 | pr_info("GRE over IPv4 tunneling driver\n"); | |
1187 | ||
1188 | err = register_pernet_device(&ipgre_net_ops); | |
1189 | if (err < 0) | |
1190 | return err; | |
1191 | ||
1192 | err = register_pernet_device(&ipgre_tap_net_ops); | |
1193 | if (err < 0) | |
1194 | goto pnet_tap_faied; | |
1195 | ||
1196 | err = gre_add_protocol(&ipgre_protocol, GREPROTO_CISCO); | |
1197 | if (err < 0) { | |
1198 | pr_info("%s: can't add protocol\n", __func__); | |
1199 | goto add_proto_failed; | |
1200 | } | |
1201 | ||
1202 | err = rtnl_link_register(&ipgre_link_ops); | |
1203 | if (err < 0) | |
1204 | goto rtnl_link_failed; | |
1205 | ||
1206 | err = rtnl_link_register(&ipgre_tap_ops); | |
1207 | if (err < 0) | |
1208 | goto tap_ops_failed; | |
1209 | ||
1210 | return 0; | |
1211 | ||
1212 | tap_ops_failed: | |
1213 | rtnl_link_unregister(&ipgre_link_ops); | |
1214 | rtnl_link_failed: | |
1215 | gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO); | |
1216 | add_proto_failed: | |
1217 | unregister_pernet_device(&ipgre_tap_net_ops); | |
1218 | pnet_tap_faied: | |
1219 | unregister_pernet_device(&ipgre_net_ops); | |
1220 | return err; | |
1221 | } | |
1222 | ||
1223 | static void __exit ipgre_fini(void) | |
1224 | { | |
1225 | rtnl_link_unregister(&ipgre_tap_ops); | |
1226 | rtnl_link_unregister(&ipgre_link_ops); | |
1227 | gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO); | |
1228 | unregister_pernet_device(&ipgre_tap_net_ops); | |
1229 | unregister_pernet_device(&ipgre_net_ops); | |
1230 | } | |
1231 | ||
1232 | module_init(ipgre_init); | |
1233 | module_exit(ipgre_fini); | |
1234 | MODULE_LICENSE("GPL"); | |
1235 | MODULE_ALIAS_RTNL_LINK("gre"); | |
1236 | MODULE_ALIAS_RTNL_LINK("gretap"); | |
1237 | MODULE_ALIAS_NETDEV("gre0"); | |
1238 | MODULE_ALIAS_NETDEV("gretap0"); |