Commit | Line | Data |
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1da177e4 | 1 | /* |
e905a9ed | 2 | * Linux NET3: GRE over IP protocol decoder. |
1da177e4 LT |
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 | ||
afd46503 JP |
13 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
14 | ||
4fc268d2 | 15 | #include <linux/capability.h> |
1da177e4 LT |
16 | #include <linux/module.h> |
17 | #include <linux/types.h> | |
1da177e4 | 18 | #include <linux/kernel.h> |
5a0e3ad6 | 19 | #include <linux/slab.h> |
1da177e4 LT |
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> | |
2e15ea39 | 27 | #include <linux/if_vlan.h> |
1da177e4 LT |
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> | |
e1a80002 | 33 | #include <linux/etherdevice.h> |
46f25dff | 34 | #include <linux/if_ether.h> |
1da177e4 LT |
35 | |
36 | #include <net/sock.h> | |
37 | #include <net/ip.h> | |
38 | #include <net/icmp.h> | |
39 | #include <net/protocol.h> | |
c5441932 | 40 | #include <net/ip_tunnels.h> |
1da177e4 LT |
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> | |
59a4c759 PE |
46 | #include <net/net_namespace.h> |
47 | #include <net/netns/generic.h> | |
c19e654d | 48 | #include <net/rtnetlink.h> |
00959ade | 49 | #include <net/gre.h> |
2e15ea39 | 50 | #include <net/dst_metadata.h> |
1da177e4 | 51 | |
dfd56b8b | 52 | #if IS_ENABLED(CONFIG_IPV6) |
1da177e4 LT |
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), | |
6d0722a2 | 70 | and silently drop packet when it expires. It is a good |
bff52857 | 71 | solution, but it supposes maintaining new variable in ALL |
1da177e4 LT |
72 | skb, even if no tunneling is used. |
73 | ||
6d0722a2 ED |
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 | |
1da177e4 LT |
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, | |
bff52857 | 97 | taking into account fragmentation. TO be short, ttl is not solution at all. |
1da177e4 LT |
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 | |
bff52857 | 104 | rapidly degrades to value <68, where looping stops. |
1da177e4 LT |
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 | ||
1da177e4 LT |
112 | Alexey Kuznetsov. |
113 | */ | |
114 | ||
eccc1bb8 | 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 | ||
c19e654d | 119 | static struct rtnl_link_ops ipgre_link_ops __read_mostly; |
1da177e4 | 120 | static int ipgre_tunnel_init(struct net_device *dev); |
eb8ce741 | 121 | |
f99189b1 | 122 | static int ipgre_net_id __read_mostly; |
c5441932 | 123 | static int gre_tap_net_id __read_mostly; |
1da177e4 | 124 | |
9f57c67c PS |
125 | static int ip_gre_calc_hlen(__be16 o_flags) |
126 | { | |
127 | int addend = 4; | |
128 | ||
129 | if (o_flags & TUNNEL_CSUM) | |
130 | addend += 4; | |
131 | if (o_flags & TUNNEL_KEY) | |
132 | addend += 4; | |
133 | if (o_flags & TUNNEL_SEQ) | |
134 | addend += 4; | |
135 | return addend; | |
136 | } | |
137 | ||
138 | static __be16 gre_flags_to_tnl_flags(__be16 flags) | |
139 | { | |
140 | __be16 tflags = 0; | |
141 | ||
142 | if (flags & GRE_CSUM) | |
143 | tflags |= TUNNEL_CSUM; | |
144 | if (flags & GRE_ROUTING) | |
145 | tflags |= TUNNEL_ROUTING; | |
146 | if (flags & GRE_KEY) | |
147 | tflags |= TUNNEL_KEY; | |
148 | if (flags & GRE_SEQ) | |
149 | tflags |= TUNNEL_SEQ; | |
150 | if (flags & GRE_STRICT) | |
151 | tflags |= TUNNEL_STRICT; | |
152 | if (flags & GRE_REC) | |
153 | tflags |= TUNNEL_REC; | |
154 | if (flags & GRE_VERSION) | |
155 | tflags |= TUNNEL_VERSION; | |
156 | ||
157 | return tflags; | |
158 | } | |
159 | ||
160 | static __be16 tnl_flags_to_gre_flags(__be16 tflags) | |
161 | { | |
162 | __be16 flags = 0; | |
163 | ||
164 | if (tflags & TUNNEL_CSUM) | |
165 | flags |= GRE_CSUM; | |
166 | if (tflags & TUNNEL_ROUTING) | |
167 | flags |= GRE_ROUTING; | |
168 | if (tflags & TUNNEL_KEY) | |
169 | flags |= GRE_KEY; | |
170 | if (tflags & TUNNEL_SEQ) | |
171 | flags |= GRE_SEQ; | |
172 | if (tflags & TUNNEL_STRICT) | |
173 | flags |= GRE_STRICT; | |
174 | if (tflags & TUNNEL_REC) | |
175 | flags |= GRE_REC; | |
176 | if (tflags & TUNNEL_VERSION) | |
177 | flags |= GRE_VERSION; | |
178 | ||
179 | return flags; | |
180 | } | |
181 | ||
b7f8fe25 | 182 | /* Fills in tpi and returns header length to be pulled. */ |
9f57c67c PS |
183 | static int parse_gre_header(struct sk_buff *skb, struct tnl_ptk_info *tpi, |
184 | bool *csum_err) | |
185 | { | |
186 | const struct gre_base_hdr *greh; | |
187 | __be32 *options; | |
188 | int hdr_len; | |
189 | ||
190 | if (unlikely(!pskb_may_pull(skb, sizeof(struct gre_base_hdr)))) | |
191 | return -EINVAL; | |
192 | ||
193 | greh = (struct gre_base_hdr *)skb_transport_header(skb); | |
194 | if (unlikely(greh->flags & (GRE_VERSION | GRE_ROUTING))) | |
195 | return -EINVAL; | |
196 | ||
197 | tpi->flags = gre_flags_to_tnl_flags(greh->flags); | |
198 | hdr_len = ip_gre_calc_hlen(tpi->flags); | |
199 | ||
200 | if (!pskb_may_pull(skb, hdr_len)) | |
201 | return -EINVAL; | |
202 | ||
203 | greh = (struct gre_base_hdr *)skb_transport_header(skb); | |
204 | tpi->proto = greh->protocol; | |
205 | ||
206 | options = (__be32 *)(greh + 1); | |
207 | if (greh->flags & GRE_CSUM) { | |
208 | if (skb_checksum_simple_validate(skb)) { | |
209 | *csum_err = true; | |
210 | return -EINVAL; | |
211 | } | |
212 | ||
213 | skb_checksum_try_convert(skb, IPPROTO_GRE, 0, | |
214 | null_compute_pseudo); | |
215 | options++; | |
216 | } | |
217 | ||
218 | if (greh->flags & GRE_KEY) { | |
219 | tpi->key = *options; | |
220 | options++; | |
221 | } else { | |
222 | tpi->key = 0; | |
223 | } | |
224 | if (unlikely(greh->flags & GRE_SEQ)) { | |
225 | tpi->seq = *options; | |
226 | options++; | |
227 | } else { | |
228 | tpi->seq = 0; | |
229 | } | |
230 | /* WCCP version 1 and 2 protocol decoding. | |
231 | * - Change protocol to IP | |
232 | * - When dealing with WCCPv2, Skip extra 4 bytes in GRE header | |
233 | */ | |
234 | if (greh->flags == 0 && tpi->proto == htons(ETH_P_WCCP)) { | |
235 | tpi->proto = htons(ETH_P_IP); | |
236 | if ((*(u8 *)options & 0xF0) != 0x40) { | |
237 | hdr_len += 4; | |
238 | if (!pskb_may_pull(skb, hdr_len)) | |
239 | return -EINVAL; | |
240 | } | |
241 | } | |
b7f8fe25 | 242 | return hdr_len; |
9f57c67c PS |
243 | } |
244 | ||
245 | static void ipgre_err(struct sk_buff *skb, u32 info, | |
246 | const struct tnl_ptk_info *tpi) | |
1da177e4 | 247 | { |
1da177e4 | 248 | |
c5441932 PS |
249 | /* All the routers (except for Linux) return only |
250 | 8 bytes of packet payload. It means, that precise relaying of | |
251 | ICMP in the real Internet is absolutely infeasible. | |
1da177e4 | 252 | |
c5441932 PS |
253 | Moreover, Cisco "wise men" put GRE key to the third word |
254 | in GRE header. It makes impossible maintaining even soft | |
255 | state for keyed GRE tunnels with enabled checksum. Tell | |
256 | them "thank you". | |
1da177e4 | 257 | |
c5441932 PS |
258 | Well, I wonder, rfc1812 was written by Cisco employee, |
259 | what the hell these idiots break standards established | |
260 | by themselves??? | |
261 | */ | |
262 | struct net *net = dev_net(skb->dev); | |
263 | struct ip_tunnel_net *itn; | |
96f5a846 | 264 | const struct iphdr *iph; |
88c7664f ACM |
265 | const int type = icmp_hdr(skb)->type; |
266 | const int code = icmp_hdr(skb)->code; | |
1da177e4 | 267 | struct ip_tunnel *t; |
1da177e4 | 268 | |
1da177e4 LT |
269 | switch (type) { |
270 | default: | |
271 | case ICMP_PARAMETERPROB: | |
9f57c67c | 272 | return; |
1da177e4 LT |
273 | |
274 | case ICMP_DEST_UNREACH: | |
275 | switch (code) { | |
276 | case ICMP_SR_FAILED: | |
277 | case ICMP_PORT_UNREACH: | |
278 | /* Impossible event. */ | |
9f57c67c | 279 | return; |
1da177e4 LT |
280 | default: |
281 | /* All others are translated to HOST_UNREACH. | |
282 | rfc2003 contains "deep thoughts" about NET_UNREACH, | |
283 | I believe they are just ether pollution. --ANK | |
284 | */ | |
285 | break; | |
286 | } | |
287 | break; | |
9f57c67c | 288 | |
1da177e4 LT |
289 | case ICMP_TIME_EXCEEDED: |
290 | if (code != ICMP_EXC_TTL) | |
9f57c67c | 291 | return; |
1da177e4 | 292 | break; |
55be7a9c DM |
293 | |
294 | case ICMP_REDIRECT: | |
295 | break; | |
1da177e4 LT |
296 | } |
297 | ||
bda7bb46 | 298 | if (tpi->proto == htons(ETH_P_TEB)) |
c5441932 PS |
299 | itn = net_generic(net, gre_tap_net_id); |
300 | else | |
301 | itn = net_generic(net, ipgre_net_id); | |
302 | ||
c0c0c50f | 303 | iph = (const struct iphdr *)(icmp_hdr(skb) + 1); |
bda7bb46 PS |
304 | t = ip_tunnel_lookup(itn, skb->dev->ifindex, tpi->flags, |
305 | iph->daddr, iph->saddr, tpi->key); | |
d2083287 | 306 | |
51456b29 | 307 | if (!t) |
9f57c67c | 308 | return; |
36393395 | 309 | |
36393395 | 310 | if (t->parms.iph.daddr == 0 || |
f97c1e0c | 311 | ipv4_is_multicast(t->parms.iph.daddr)) |
9f57c67c | 312 | return; |
1da177e4 LT |
313 | |
314 | if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED) | |
9f57c67c | 315 | return; |
1da177e4 | 316 | |
da6185d8 | 317 | if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO)) |
1da177e4 LT |
318 | t->err_count++; |
319 | else | |
320 | t->err_count = 1; | |
321 | t->err_time = jiffies; | |
9f57c67c PS |
322 | } |
323 | ||
324 | static void gre_err(struct sk_buff *skb, u32 info) | |
325 | { | |
326 | /* All the routers (except for Linux) return only | |
327 | * 8 bytes of packet payload. It means, that precise relaying of | |
328 | * ICMP in the real Internet is absolutely infeasible. | |
329 | * | |
330 | * Moreover, Cisco "wise men" put GRE key to the third word | |
331 | * in GRE header. It makes impossible maintaining even soft | |
332 | * state for keyed | |
333 | * GRE tunnels with enabled checksum. Tell them "thank you". | |
334 | * | |
335 | * Well, I wonder, rfc1812 was written by Cisco employee, | |
336 | * what the hell these idiots break standards established | |
337 | * by themselves??? | |
338 | */ | |
339 | ||
340 | const int type = icmp_hdr(skb)->type; | |
341 | const int code = icmp_hdr(skb)->code; | |
342 | struct tnl_ptk_info tpi; | |
343 | bool csum_err = false; | |
344 | ||
b7f8fe25 | 345 | if (parse_gre_header(skb, &tpi, &csum_err) < 0) { |
9f57c67c PS |
346 | if (!csum_err) /* ignore csum errors. */ |
347 | return; | |
348 | } | |
349 | ||
350 | if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) { | |
351 | ipv4_update_pmtu(skb, dev_net(skb->dev), info, | |
352 | skb->dev->ifindex, 0, IPPROTO_GRE, 0); | |
353 | return; | |
354 | } | |
355 | if (type == ICMP_REDIRECT) { | |
356 | ipv4_redirect(skb, dev_net(skb->dev), skb->dev->ifindex, 0, | |
357 | IPPROTO_GRE, 0); | |
358 | return; | |
359 | } | |
360 | ||
361 | ipgre_err(skb, info, &tpi); | |
1da177e4 LT |
362 | } |
363 | ||
2e15ea39 PS |
364 | static __be64 key_to_tunnel_id(__be32 key) |
365 | { | |
366 | #ifdef __BIG_ENDIAN | |
367 | return (__force __be64)((__force u32)key); | |
368 | #else | |
369 | return (__force __be64)((__force u64)key << 32); | |
370 | #endif | |
371 | } | |
372 | ||
373 | /* Returns the least-significant 32 bits of a __be64. */ | |
374 | static __be32 tunnel_id_to_key(__be64 x) | |
375 | { | |
376 | #ifdef __BIG_ENDIAN | |
377 | return (__force __be32)x; | |
378 | #else | |
379 | return (__force __be32)((__force u64)x >> 32); | |
380 | #endif | |
381 | } | |
382 | ||
bda7bb46 | 383 | static int ipgre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi) |
1da177e4 | 384 | { |
c5441932 | 385 | struct net *net = dev_net(skb->dev); |
2e15ea39 | 386 | struct metadata_dst *tun_dst = NULL; |
c5441932 | 387 | struct ip_tunnel_net *itn; |
b71d1d42 | 388 | const struct iphdr *iph; |
1da177e4 | 389 | struct ip_tunnel *tunnel; |
1da177e4 | 390 | |
bda7bb46 | 391 | if (tpi->proto == htons(ETH_P_TEB)) |
c5441932 PS |
392 | itn = net_generic(net, gre_tap_net_id); |
393 | else | |
394 | itn = net_generic(net, ipgre_net_id); | |
1da177e4 | 395 | |
c5441932 | 396 | iph = ip_hdr(skb); |
bda7bb46 PS |
397 | tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, tpi->flags, |
398 | iph->saddr, iph->daddr, tpi->key); | |
e1a80002 | 399 | |
d2083287 | 400 | if (tunnel) { |
e271c7b4 JB |
401 | if (tunnel->dev->type != ARPHRD_NONE) |
402 | skb_pop_mac_header(skb); | |
403 | else | |
404 | skb_reset_mac_header(skb); | |
2e15ea39 | 405 | if (tunnel->collect_md) { |
c29a70d2 PS |
406 | __be16 flags; |
407 | __be64 tun_id; | |
2e15ea39 | 408 | |
c29a70d2 PS |
409 | flags = tpi->flags & (TUNNEL_CSUM | TUNNEL_KEY); |
410 | tun_id = key_to_tunnel_id(tpi->key); | |
411 | tun_dst = ip_tun_rx_dst(skb, flags, tun_id, 0); | |
2e15ea39 PS |
412 | if (!tun_dst) |
413 | return PACKET_REJECT; | |
2e15ea39 PS |
414 | } |
415 | ||
416 | ip_tunnel_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error); | |
bda7bb46 | 417 | return PACKET_RCVD; |
1da177e4 | 418 | } |
bda7bb46 | 419 | return PACKET_REJECT; |
1da177e4 LT |
420 | } |
421 | ||
9f57c67c PS |
422 | static int gre_rcv(struct sk_buff *skb) |
423 | { | |
424 | struct tnl_ptk_info tpi; | |
425 | bool csum_err = false; | |
b7f8fe25 | 426 | int hdr_len; |
9f57c67c PS |
427 | |
428 | #ifdef CONFIG_NET_IPGRE_BROADCAST | |
429 | if (ipv4_is_multicast(ip_hdr(skb)->daddr)) { | |
430 | /* Looped back packet, drop it! */ | |
431 | if (rt_is_output_route(skb_rtable(skb))) | |
432 | goto drop; | |
433 | } | |
434 | #endif | |
435 | ||
b7f8fe25 JB |
436 | hdr_len = parse_gre_header(skb, &tpi, &csum_err); |
437 | if (hdr_len < 0) | |
438 | goto drop; | |
439 | if (iptunnel_pull_header(skb, hdr_len, tpi.proto, false) < 0) | |
9f57c67c PS |
440 | goto drop; |
441 | ||
442 | if (ipgre_rcv(skb, &tpi) == PACKET_RCVD) | |
443 | return 0; | |
444 | ||
445 | icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0); | |
446 | drop: | |
447 | kfree_skb(skb); | |
448 | return 0; | |
449 | } | |
450 | ||
53936107 EC |
451 | static __sum16 gre_checksum(struct sk_buff *skb) |
452 | { | |
453 | __wsum csum; | |
454 | ||
455 | if (skb->ip_summed == CHECKSUM_PARTIAL) | |
456 | csum = lco_csum(skb); | |
457 | else | |
458 | csum = skb_checksum(skb, 0, skb->len, 0); | |
459 | return csum_fold(csum); | |
460 | } | |
461 | ||
2e15ea39 PS |
462 | static void build_header(struct sk_buff *skb, int hdr_len, __be16 flags, |
463 | __be16 proto, __be32 key, __be32 seq) | |
464 | { | |
465 | struct gre_base_hdr *greh; | |
466 | ||
467 | skb_push(skb, hdr_len); | |
468 | ||
469 | skb_reset_transport_header(skb); | |
470 | greh = (struct gre_base_hdr *)skb->data; | |
471 | greh->flags = tnl_flags_to_gre_flags(flags); | |
472 | greh->protocol = proto; | |
473 | ||
474 | if (flags & (TUNNEL_KEY | TUNNEL_CSUM | TUNNEL_SEQ)) { | |
475 | __be32 *ptr = (__be32 *)(((u8 *)greh) + hdr_len - 4); | |
476 | ||
477 | if (flags & TUNNEL_SEQ) { | |
478 | *ptr = seq; | |
479 | ptr--; | |
480 | } | |
481 | if (flags & TUNNEL_KEY) { | |
482 | *ptr = key; | |
483 | ptr--; | |
484 | } | |
485 | if (flags & TUNNEL_CSUM && | |
486 | !(skb_shinfo(skb)->gso_type & | |
487 | (SKB_GSO_GRE | SKB_GSO_GRE_CSUM))) { | |
488 | *ptr = 0; | |
53936107 | 489 | *(__sum16 *)ptr = gre_checksum(skb); |
2e15ea39 PS |
490 | } |
491 | } | |
492 | } | |
493 | ||
c5441932 PS |
494 | static void __gre_xmit(struct sk_buff *skb, struct net_device *dev, |
495 | const struct iphdr *tnl_params, | |
496 | __be16 proto) | |
497 | { | |
498 | struct ip_tunnel *tunnel = netdev_priv(dev); | |
1da177e4 | 499 | |
c5441932 PS |
500 | if (tunnel->parms.o_flags & TUNNEL_SEQ) |
501 | tunnel->o_seqno++; | |
1da177e4 | 502 | |
c5441932 | 503 | /* Push GRE header. */ |
2e15ea39 PS |
504 | build_header(skb, tunnel->tun_hlen, tunnel->parms.o_flags, |
505 | proto, tunnel->parms.o_key, htonl(tunnel->o_seqno)); | |
54bc9bac | 506 | |
2e15ea39 | 507 | skb_set_inner_protocol(skb, proto); |
bf3d6a8f | 508 | ip_tunnel_xmit(skb, dev, tnl_params, tnl_params->protocol); |
c5441932 | 509 | } |
1da177e4 | 510 | |
b2acd1dc PS |
511 | static struct sk_buff *gre_handle_offloads(struct sk_buff *skb, |
512 | bool csum) | |
513 | { | |
6fa79666 | 514 | return iptunnel_handle_offloads(skb, csum ? SKB_GSO_GRE_CSUM : SKB_GSO_GRE); |
b2acd1dc PS |
515 | } |
516 | ||
fc4099f1 PS |
517 | static struct rtable *gre_get_rt(struct sk_buff *skb, |
518 | struct net_device *dev, | |
519 | struct flowi4 *fl, | |
520 | const struct ip_tunnel_key *key) | |
521 | { | |
522 | struct net *net = dev_net(dev); | |
523 | ||
524 | memset(fl, 0, sizeof(*fl)); | |
525 | fl->daddr = key->u.ipv4.dst; | |
526 | fl->saddr = key->u.ipv4.src; | |
527 | fl->flowi4_tos = RT_TOS(key->tos); | |
528 | fl->flowi4_mark = skb->mark; | |
529 | fl->flowi4_proto = IPPROTO_GRE; | |
530 | ||
531 | return ip_route_output_key(net, fl); | |
532 | } | |
533 | ||
2090714e JB |
534 | static void gre_fb_xmit(struct sk_buff *skb, struct net_device *dev, |
535 | __be16 proto) | |
2e15ea39 PS |
536 | { |
537 | struct ip_tunnel_info *tun_info; | |
2e15ea39 | 538 | const struct ip_tunnel_key *key; |
db3c6139 | 539 | struct rtable *rt = NULL; |
2e15ea39 | 540 | struct flowi4 fl; |
2e15ea39 PS |
541 | int min_headroom; |
542 | int tunnel_hlen; | |
543 | __be16 df, flags; | |
db3c6139 | 544 | bool use_cache; |
2e15ea39 PS |
545 | int err; |
546 | ||
61adedf3 | 547 | tun_info = skb_tunnel_info(skb); |
7f9562a1 JB |
548 | if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) || |
549 | ip_tunnel_info_af(tun_info) != AF_INET)) | |
2e15ea39 PS |
550 | goto err_free_skb; |
551 | ||
552 | key = &tun_info->key; | |
db3c6139 DB |
553 | use_cache = ip_tunnel_dst_cache_usable(skb, tun_info); |
554 | if (use_cache) | |
555 | rt = dst_cache_get_ip4(&tun_info->dst_cache, &fl.saddr); | |
3c1cb4d2 PA |
556 | if (!rt) { |
557 | rt = gre_get_rt(skb, dev, &fl, key); | |
558 | if (IS_ERR(rt)) | |
559 | goto err_free_skb; | |
db3c6139 | 560 | if (use_cache) |
3c1cb4d2 PA |
561 | dst_cache_set_ip4(&tun_info->dst_cache, &rt->dst, |
562 | fl.saddr); | |
563 | } | |
2e15ea39 PS |
564 | |
565 | tunnel_hlen = ip_gre_calc_hlen(key->tun_flags); | |
566 | ||
567 | min_headroom = LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len | |
568 | + tunnel_hlen + sizeof(struct iphdr); | |
569 | if (skb_headroom(skb) < min_headroom || skb_header_cloned(skb)) { | |
570 | int head_delta = SKB_DATA_ALIGN(min_headroom - | |
571 | skb_headroom(skb) + | |
572 | 16); | |
573 | err = pskb_expand_head(skb, max_t(int, head_delta, 0), | |
574 | 0, GFP_ATOMIC); | |
575 | if (unlikely(err)) | |
576 | goto err_free_rt; | |
577 | } | |
578 | ||
579 | /* Push Tunnel header. */ | |
580 | skb = gre_handle_offloads(skb, !!(tun_info->key.tun_flags & TUNNEL_CSUM)); | |
581 | if (IS_ERR(skb)) { | |
582 | skb = NULL; | |
583 | goto err_free_rt; | |
584 | } | |
585 | ||
586 | flags = tun_info->key.tun_flags & (TUNNEL_CSUM | TUNNEL_KEY); | |
2090714e | 587 | build_header(skb, tunnel_hlen, flags, proto, |
2e15ea39 PS |
588 | tunnel_id_to_key(tun_info->key.tun_id), 0); |
589 | ||
590 | df = key->tun_flags & TUNNEL_DONT_FRAGMENT ? htons(IP_DF) : 0; | |
039f5062 PS |
591 | |
592 | iptunnel_xmit(skb->sk, rt, skb, fl.saddr, key->u.ipv4.dst, IPPROTO_GRE, | |
593 | key->tos, key->ttl, df, false); | |
2e15ea39 PS |
594 | return; |
595 | ||
596 | err_free_rt: | |
597 | ip_rt_put(rt); | |
598 | err_free_skb: | |
599 | kfree_skb(skb); | |
600 | dev->stats.tx_dropped++; | |
601 | } | |
602 | ||
fc4099f1 PS |
603 | static int gre_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb) |
604 | { | |
605 | struct ip_tunnel_info *info = skb_tunnel_info(skb); | |
606 | struct rtable *rt; | |
607 | struct flowi4 fl4; | |
608 | ||
609 | if (ip_tunnel_info_af(info) != AF_INET) | |
610 | return -EINVAL; | |
611 | ||
612 | rt = gre_get_rt(skb, dev, &fl4, &info->key); | |
613 | if (IS_ERR(rt)) | |
614 | return PTR_ERR(rt); | |
615 | ||
616 | ip_rt_put(rt); | |
617 | info->key.u.ipv4.src = fl4.saddr; | |
618 | return 0; | |
619 | } | |
620 | ||
c5441932 PS |
621 | static netdev_tx_t ipgre_xmit(struct sk_buff *skb, |
622 | struct net_device *dev) | |
623 | { | |
624 | struct ip_tunnel *tunnel = netdev_priv(dev); | |
625 | const struct iphdr *tnl_params; | |
1da177e4 | 626 | |
2e15ea39 | 627 | if (tunnel->collect_md) { |
2090714e | 628 | gre_fb_xmit(skb, dev, skb->protocol); |
2e15ea39 PS |
629 | return NETDEV_TX_OK; |
630 | } | |
631 | ||
c5441932 PS |
632 | if (dev->header_ops) { |
633 | /* Need space for new headers */ | |
634 | if (skb_cow_head(skb, dev->needed_headroom - | |
2bac7cb3 | 635 | (tunnel->hlen + sizeof(struct iphdr)))) |
c5441932 | 636 | goto free_skb; |
1da177e4 | 637 | |
c5441932 | 638 | tnl_params = (const struct iphdr *)skb->data; |
1da177e4 | 639 | |
c5441932 PS |
640 | /* Pull skb since ip_tunnel_xmit() needs skb->data pointing |
641 | * to gre header. | |
642 | */ | |
643 | skb_pull(skb, tunnel->hlen + sizeof(struct iphdr)); | |
8a0033a9 | 644 | skb_reset_mac_header(skb); |
c5441932 PS |
645 | } else { |
646 | if (skb_cow_head(skb, dev->needed_headroom)) | |
647 | goto free_skb; | |
1da177e4 | 648 | |
c5441932 | 649 | tnl_params = &tunnel->parms.iph; |
1da177e4 LT |
650 | } |
651 | ||
8a0033a9 TT |
652 | skb = gre_handle_offloads(skb, !!(tunnel->parms.o_flags&TUNNEL_CSUM)); |
653 | if (IS_ERR(skb)) | |
654 | goto out; | |
655 | ||
c5441932 | 656 | __gre_xmit(skb, dev, tnl_params, skb->protocol); |
6ed10654 | 657 | return NETDEV_TX_OK; |
1da177e4 | 658 | |
c5441932 | 659 | free_skb: |
3acfa1e7 | 660 | kfree_skb(skb); |
c5441932 PS |
661 | out: |
662 | dev->stats.tx_dropped++; | |
6ed10654 | 663 | return NETDEV_TX_OK; |
1da177e4 LT |
664 | } |
665 | ||
c5441932 PS |
666 | static netdev_tx_t gre_tap_xmit(struct sk_buff *skb, |
667 | struct net_device *dev) | |
ee34c1eb | 668 | { |
c5441932 | 669 | struct ip_tunnel *tunnel = netdev_priv(dev); |
ee34c1eb | 670 | |
2e15ea39 | 671 | if (tunnel->collect_md) { |
2090714e | 672 | gre_fb_xmit(skb, dev, htons(ETH_P_TEB)); |
2e15ea39 PS |
673 | return NETDEV_TX_OK; |
674 | } | |
675 | ||
45f2e997 | 676 | skb = gre_handle_offloads(skb, !!(tunnel->parms.o_flags&TUNNEL_CSUM)); |
c5441932 PS |
677 | if (IS_ERR(skb)) |
678 | goto out; | |
ee34c1eb | 679 | |
c5441932 PS |
680 | if (skb_cow_head(skb, dev->needed_headroom)) |
681 | goto free_skb; | |
42aa9162 | 682 | |
c5441932 | 683 | __gre_xmit(skb, dev, &tunnel->parms.iph, htons(ETH_P_TEB)); |
c5441932 | 684 | return NETDEV_TX_OK; |
ee34c1eb | 685 | |
c5441932 | 686 | free_skb: |
3acfa1e7 | 687 | kfree_skb(skb); |
c5441932 PS |
688 | out: |
689 | dev->stats.tx_dropped++; | |
690 | return NETDEV_TX_OK; | |
ee34c1eb MS |
691 | } |
692 | ||
c5441932 PS |
693 | static int ipgre_tunnel_ioctl(struct net_device *dev, |
694 | struct ifreq *ifr, int cmd) | |
1da177e4 | 695 | { |
4565e991 | 696 | int err; |
1da177e4 | 697 | struct ip_tunnel_parm p; |
1da177e4 | 698 | |
c5441932 PS |
699 | if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) |
700 | return -EFAULT; | |
6c734fb8 CW |
701 | if (cmd == SIOCADDTUNNEL || cmd == SIOCCHGTUNNEL) { |
702 | if (p.iph.version != 4 || p.iph.protocol != IPPROTO_GRE || | |
703 | p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF)) || | |
704 | ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING))) | |
705 | return -EINVAL; | |
1da177e4 | 706 | } |
c5441932 PS |
707 | p.i_flags = gre_flags_to_tnl_flags(p.i_flags); |
708 | p.o_flags = gre_flags_to_tnl_flags(p.o_flags); | |
1da177e4 | 709 | |
c5441932 PS |
710 | err = ip_tunnel_ioctl(dev, &p, cmd); |
711 | if (err) | |
712 | return err; | |
1da177e4 | 713 | |
c5441932 PS |
714 | p.i_flags = tnl_flags_to_gre_flags(p.i_flags); |
715 | p.o_flags = tnl_flags_to_gre_flags(p.o_flags); | |
716 | ||
717 | if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) | |
718 | return -EFAULT; | |
1da177e4 LT |
719 | return 0; |
720 | } | |
721 | ||
1da177e4 LT |
722 | /* Nice toy. Unfortunately, useless in real life :-) |
723 | It allows to construct virtual multiprotocol broadcast "LAN" | |
724 | over the Internet, provided multicast routing is tuned. | |
725 | ||
726 | ||
727 | I have no idea was this bicycle invented before me, | |
728 | so that I had to set ARPHRD_IPGRE to a random value. | |
729 | I have an impression, that Cisco could make something similar, | |
730 | but this feature is apparently missing in IOS<=11.2(8). | |
e905a9ed | 731 | |
1da177e4 LT |
732 | I set up 10.66.66/24 and fec0:6666:6666::0/96 as virtual networks |
733 | with broadcast 224.66.66.66. If you have access to mbone, play with me :-) | |
734 | ||
735 | ping -t 255 224.66.66.66 | |
736 | ||
737 | If nobody answers, mbone does not work. | |
738 | ||
739 | ip tunnel add Universe mode gre remote 224.66.66.66 local <Your_real_addr> ttl 255 | |
740 | ip addr add 10.66.66.<somewhat>/24 dev Universe | |
741 | ifconfig Universe up | |
742 | ifconfig Universe add fe80::<Your_real_addr>/10 | |
743 | ifconfig Universe add fec0:6666:6666::<Your_real_addr>/96 | |
744 | ftp 10.66.66.66 | |
745 | ... | |
746 | ftp fec0:6666:6666::193.233.7.65 | |
747 | ... | |
1da177e4 | 748 | */ |
3b04ddde SH |
749 | static int ipgre_header(struct sk_buff *skb, struct net_device *dev, |
750 | unsigned short type, | |
1507850b | 751 | const void *daddr, const void *saddr, unsigned int len) |
1da177e4 | 752 | { |
2941a486 | 753 | struct ip_tunnel *t = netdev_priv(dev); |
c5441932 PS |
754 | struct iphdr *iph; |
755 | struct gre_base_hdr *greh; | |
1da177e4 | 756 | |
c5441932 PS |
757 | iph = (struct iphdr *)skb_push(skb, t->hlen + sizeof(*iph)); |
758 | greh = (struct gre_base_hdr *)(iph+1); | |
759 | greh->flags = tnl_flags_to_gre_flags(t->parms.o_flags); | |
760 | greh->protocol = htons(type); | |
1da177e4 | 761 | |
c5441932 | 762 | memcpy(iph, &t->parms.iph, sizeof(struct iphdr)); |
e905a9ed | 763 | |
c5441932 | 764 | /* Set the source hardware address. */ |
1da177e4 LT |
765 | if (saddr) |
766 | memcpy(&iph->saddr, saddr, 4); | |
6d55cb91 | 767 | if (daddr) |
1da177e4 | 768 | memcpy(&iph->daddr, daddr, 4); |
6d55cb91 | 769 | if (iph->daddr) |
77a482bd | 770 | return t->hlen + sizeof(*iph); |
e905a9ed | 771 | |
c5441932 | 772 | return -(t->hlen + sizeof(*iph)); |
1da177e4 LT |
773 | } |
774 | ||
6a5f44d7 TT |
775 | static int ipgre_header_parse(const struct sk_buff *skb, unsigned char *haddr) |
776 | { | |
b71d1d42 | 777 | const struct iphdr *iph = (const struct iphdr *) skb_mac_header(skb); |
6a5f44d7 TT |
778 | memcpy(haddr, &iph->saddr, 4); |
779 | return 4; | |
780 | } | |
781 | ||
3b04ddde SH |
782 | static const struct header_ops ipgre_header_ops = { |
783 | .create = ipgre_header, | |
6a5f44d7 | 784 | .parse = ipgre_header_parse, |
3b04ddde SH |
785 | }; |
786 | ||
6a5f44d7 | 787 | #ifdef CONFIG_NET_IPGRE_BROADCAST |
1da177e4 LT |
788 | static int ipgre_open(struct net_device *dev) |
789 | { | |
2941a486 | 790 | struct ip_tunnel *t = netdev_priv(dev); |
1da177e4 | 791 | |
f97c1e0c | 792 | if (ipv4_is_multicast(t->parms.iph.daddr)) { |
cbb1e85f DM |
793 | struct flowi4 fl4; |
794 | struct rtable *rt; | |
795 | ||
b57708ad | 796 | rt = ip_route_output_gre(t->net, &fl4, |
cbb1e85f DM |
797 | t->parms.iph.daddr, |
798 | t->parms.iph.saddr, | |
799 | t->parms.o_key, | |
800 | RT_TOS(t->parms.iph.tos), | |
801 | t->parms.link); | |
b23dd4fe | 802 | if (IS_ERR(rt)) |
1da177e4 | 803 | return -EADDRNOTAVAIL; |
d8d1f30b | 804 | dev = rt->dst.dev; |
1da177e4 | 805 | ip_rt_put(rt); |
51456b29 | 806 | if (!__in_dev_get_rtnl(dev)) |
1da177e4 LT |
807 | return -EADDRNOTAVAIL; |
808 | t->mlink = dev->ifindex; | |
e5ed6399 | 809 | ip_mc_inc_group(__in_dev_get_rtnl(dev), t->parms.iph.daddr); |
1da177e4 LT |
810 | } |
811 | return 0; | |
812 | } | |
813 | ||
814 | static int ipgre_close(struct net_device *dev) | |
815 | { | |
2941a486 | 816 | struct ip_tunnel *t = netdev_priv(dev); |
b8c26a33 | 817 | |
f97c1e0c | 818 | if (ipv4_is_multicast(t->parms.iph.daddr) && t->mlink) { |
7fee0ca2 | 819 | struct in_device *in_dev; |
b57708ad | 820 | in_dev = inetdev_by_index(t->net, t->mlink); |
8723e1b4 | 821 | if (in_dev) |
1da177e4 | 822 | ip_mc_dec_group(in_dev, t->parms.iph.daddr); |
1da177e4 LT |
823 | } |
824 | return 0; | |
825 | } | |
1da177e4 LT |
826 | #endif |
827 | ||
b8c26a33 SH |
828 | static const struct net_device_ops ipgre_netdev_ops = { |
829 | .ndo_init = ipgre_tunnel_init, | |
c5441932 | 830 | .ndo_uninit = ip_tunnel_uninit, |
b8c26a33 SH |
831 | #ifdef CONFIG_NET_IPGRE_BROADCAST |
832 | .ndo_open = ipgre_open, | |
833 | .ndo_stop = ipgre_close, | |
834 | #endif | |
c5441932 | 835 | .ndo_start_xmit = ipgre_xmit, |
b8c26a33 | 836 | .ndo_do_ioctl = ipgre_tunnel_ioctl, |
c5441932 PS |
837 | .ndo_change_mtu = ip_tunnel_change_mtu, |
838 | .ndo_get_stats64 = ip_tunnel_get_stats64, | |
1e99584b | 839 | .ndo_get_iflink = ip_tunnel_get_iflink, |
b8c26a33 SH |
840 | }; |
841 | ||
6b78f16e ED |
842 | #define GRE_FEATURES (NETIF_F_SG | \ |
843 | NETIF_F_FRAGLIST | \ | |
844 | NETIF_F_HIGHDMA | \ | |
845 | NETIF_F_HW_CSUM) | |
846 | ||
1da177e4 LT |
847 | static void ipgre_tunnel_setup(struct net_device *dev) |
848 | { | |
b8c26a33 | 849 | dev->netdev_ops = &ipgre_netdev_ops; |
5a455275 | 850 | dev->type = ARPHRD_IPGRE; |
c5441932 PS |
851 | ip_tunnel_setup(dev, ipgre_net_id); |
852 | } | |
1da177e4 | 853 | |
c5441932 PS |
854 | static void __gre_tunnel_init(struct net_device *dev) |
855 | { | |
856 | struct ip_tunnel *tunnel; | |
4565e991 | 857 | int t_hlen; |
c5441932 PS |
858 | |
859 | tunnel = netdev_priv(dev); | |
4565e991 | 860 | tunnel->tun_hlen = ip_gre_calc_hlen(tunnel->parms.o_flags); |
c5441932 PS |
861 | tunnel->parms.iph.protocol = IPPROTO_GRE; |
862 | ||
4565e991 TH |
863 | tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen; |
864 | ||
865 | t_hlen = tunnel->hlen + sizeof(struct iphdr); | |
866 | ||
867 | dev->needed_headroom = LL_MAX_HEADER + t_hlen + 4; | |
868 | dev->mtu = ETH_DATA_LEN - t_hlen - 4; | |
6b78f16e | 869 | |
b57708ad | 870 | dev->features |= GRE_FEATURES; |
6b78f16e | 871 | dev->hw_features |= GRE_FEATURES; |
c5441932 PS |
872 | |
873 | if (!(tunnel->parms.o_flags & TUNNEL_SEQ)) { | |
a0ca153f AD |
874 | /* TCP offload with GRE SEQ is not supported, nor |
875 | * can we support 2 levels of outer headers requiring | |
876 | * an update. | |
877 | */ | |
878 | if (!(tunnel->parms.o_flags & TUNNEL_CSUM) || | |
879 | (tunnel->encap.type == TUNNEL_ENCAP_NONE)) { | |
880 | dev->features |= NETIF_F_GSO_SOFTWARE; | |
881 | dev->hw_features |= NETIF_F_GSO_SOFTWARE; | |
882 | } | |
883 | ||
c5441932 PS |
884 | /* Can use a lockless transmit, unless we generate |
885 | * output sequences | |
886 | */ | |
887 | dev->features |= NETIF_F_LLTX; | |
888 | } | |
1da177e4 LT |
889 | } |
890 | ||
891 | static int ipgre_tunnel_init(struct net_device *dev) | |
892 | { | |
c5441932 PS |
893 | struct ip_tunnel *tunnel = netdev_priv(dev); |
894 | struct iphdr *iph = &tunnel->parms.iph; | |
1da177e4 | 895 | |
c5441932 | 896 | __gre_tunnel_init(dev); |
1da177e4 | 897 | |
c5441932 PS |
898 | memcpy(dev->dev_addr, &iph->saddr, 4); |
899 | memcpy(dev->broadcast, &iph->daddr, 4); | |
1da177e4 | 900 | |
c5441932 | 901 | dev->flags = IFF_NOARP; |
02875878 | 902 | netif_keep_dst(dev); |
c5441932 | 903 | dev->addr_len = 4; |
1da177e4 | 904 | |
a64b04d8 | 905 | if (iph->daddr && !tunnel->collect_md) { |
1da177e4 | 906 | #ifdef CONFIG_NET_IPGRE_BROADCAST |
f97c1e0c | 907 | if (ipv4_is_multicast(iph->daddr)) { |
1da177e4 LT |
908 | if (!iph->saddr) |
909 | return -EINVAL; | |
910 | dev->flags = IFF_BROADCAST; | |
3b04ddde | 911 | dev->header_ops = &ipgre_header_ops; |
1da177e4 LT |
912 | } |
913 | #endif | |
a64b04d8 | 914 | } else if (!tunnel->collect_md) { |
6a5f44d7 | 915 | dev->header_ops = &ipgre_header_ops; |
a64b04d8 | 916 | } |
1da177e4 | 917 | |
c5441932 | 918 | return ip_tunnel_init(dev); |
1da177e4 LT |
919 | } |
920 | ||
9f57c67c PS |
921 | static const struct gre_protocol ipgre_protocol = { |
922 | .handler = gre_rcv, | |
923 | .err_handler = gre_err, | |
1da177e4 LT |
924 | }; |
925 | ||
2c8c1e72 | 926 | static int __net_init ipgre_init_net(struct net *net) |
59a4c759 | 927 | { |
c5441932 | 928 | return ip_tunnel_init_net(net, ipgre_net_id, &ipgre_link_ops, NULL); |
59a4c759 PE |
929 | } |
930 | ||
2c8c1e72 | 931 | static void __net_exit ipgre_exit_net(struct net *net) |
59a4c759 | 932 | { |
c5441932 | 933 | struct ip_tunnel_net *itn = net_generic(net, ipgre_net_id); |
6c742e71 | 934 | ip_tunnel_delete_net(itn, &ipgre_link_ops); |
59a4c759 PE |
935 | } |
936 | ||
937 | static struct pernet_operations ipgre_net_ops = { | |
938 | .init = ipgre_init_net, | |
939 | .exit = ipgre_exit_net, | |
cfb8fbf2 | 940 | .id = &ipgre_net_id, |
c5441932 | 941 | .size = sizeof(struct ip_tunnel_net), |
59a4c759 | 942 | }; |
1da177e4 | 943 | |
c19e654d HX |
944 | static int ipgre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[]) |
945 | { | |
946 | __be16 flags; | |
947 | ||
948 | if (!data) | |
949 | return 0; | |
950 | ||
951 | flags = 0; | |
952 | if (data[IFLA_GRE_IFLAGS]) | |
953 | flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]); | |
954 | if (data[IFLA_GRE_OFLAGS]) | |
955 | flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]); | |
956 | if (flags & (GRE_VERSION|GRE_ROUTING)) | |
957 | return -EINVAL; | |
958 | ||
946b636f JB |
959 | if (data[IFLA_GRE_COLLECT_METADATA] && |
960 | data[IFLA_GRE_ENCAP_TYPE] && | |
961 | nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]) != TUNNEL_ENCAP_NONE) | |
962 | return -EINVAL; | |
963 | ||
c19e654d HX |
964 | return 0; |
965 | } | |
966 | ||
e1a80002 HX |
967 | static int ipgre_tap_validate(struct nlattr *tb[], struct nlattr *data[]) |
968 | { | |
969 | __be32 daddr; | |
970 | ||
971 | if (tb[IFLA_ADDRESS]) { | |
972 | if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) | |
973 | return -EINVAL; | |
974 | if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) | |
975 | return -EADDRNOTAVAIL; | |
976 | } | |
977 | ||
978 | if (!data) | |
979 | goto out; | |
980 | ||
981 | if (data[IFLA_GRE_REMOTE]) { | |
982 | memcpy(&daddr, nla_data(data[IFLA_GRE_REMOTE]), 4); | |
983 | if (!daddr) | |
984 | return -EINVAL; | |
985 | } | |
986 | ||
987 | out: | |
988 | return ipgre_tunnel_validate(tb, data); | |
989 | } | |
990 | ||
2e15ea39 PS |
991 | static void ipgre_netlink_parms(struct net_device *dev, |
992 | struct nlattr *data[], | |
993 | struct nlattr *tb[], | |
994 | struct ip_tunnel_parm *parms) | |
c19e654d | 995 | { |
7bb82d92 | 996 | memset(parms, 0, sizeof(*parms)); |
c19e654d HX |
997 | |
998 | parms->iph.protocol = IPPROTO_GRE; | |
999 | ||
1000 | if (!data) | |
1001 | return; | |
1002 | ||
1003 | if (data[IFLA_GRE_LINK]) | |
1004 | parms->link = nla_get_u32(data[IFLA_GRE_LINK]); | |
1005 | ||
1006 | if (data[IFLA_GRE_IFLAGS]) | |
c5441932 | 1007 | parms->i_flags = gre_flags_to_tnl_flags(nla_get_be16(data[IFLA_GRE_IFLAGS])); |
c19e654d HX |
1008 | |
1009 | if (data[IFLA_GRE_OFLAGS]) | |
c5441932 | 1010 | parms->o_flags = gre_flags_to_tnl_flags(nla_get_be16(data[IFLA_GRE_OFLAGS])); |
c19e654d HX |
1011 | |
1012 | if (data[IFLA_GRE_IKEY]) | |
1013 | parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]); | |
1014 | ||
1015 | if (data[IFLA_GRE_OKEY]) | |
1016 | parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]); | |
1017 | ||
1018 | if (data[IFLA_GRE_LOCAL]) | |
67b61f6c | 1019 | parms->iph.saddr = nla_get_in_addr(data[IFLA_GRE_LOCAL]); |
c19e654d HX |
1020 | |
1021 | if (data[IFLA_GRE_REMOTE]) | |
67b61f6c | 1022 | parms->iph.daddr = nla_get_in_addr(data[IFLA_GRE_REMOTE]); |
c19e654d HX |
1023 | |
1024 | if (data[IFLA_GRE_TTL]) | |
1025 | parms->iph.ttl = nla_get_u8(data[IFLA_GRE_TTL]); | |
1026 | ||
1027 | if (data[IFLA_GRE_TOS]) | |
1028 | parms->iph.tos = nla_get_u8(data[IFLA_GRE_TOS]); | |
1029 | ||
1030 | if (!data[IFLA_GRE_PMTUDISC] || nla_get_u8(data[IFLA_GRE_PMTUDISC])) | |
1031 | parms->iph.frag_off = htons(IP_DF); | |
2e15ea39 PS |
1032 | |
1033 | if (data[IFLA_GRE_COLLECT_METADATA]) { | |
1034 | struct ip_tunnel *t = netdev_priv(dev); | |
1035 | ||
1036 | t->collect_md = true; | |
e271c7b4 JB |
1037 | if (dev->type == ARPHRD_IPGRE) |
1038 | dev->type = ARPHRD_NONE; | |
2e15ea39 | 1039 | } |
c19e654d HX |
1040 | } |
1041 | ||
4565e991 TH |
1042 | /* This function returns true when ENCAP attributes are present in the nl msg */ |
1043 | static bool ipgre_netlink_encap_parms(struct nlattr *data[], | |
1044 | struct ip_tunnel_encap *ipencap) | |
1045 | { | |
1046 | bool ret = false; | |
1047 | ||
1048 | memset(ipencap, 0, sizeof(*ipencap)); | |
1049 | ||
1050 | if (!data) | |
1051 | return ret; | |
1052 | ||
1053 | if (data[IFLA_GRE_ENCAP_TYPE]) { | |
1054 | ret = true; | |
1055 | ipencap->type = nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]); | |
1056 | } | |
1057 | ||
1058 | if (data[IFLA_GRE_ENCAP_FLAGS]) { | |
1059 | ret = true; | |
1060 | ipencap->flags = nla_get_u16(data[IFLA_GRE_ENCAP_FLAGS]); | |
1061 | } | |
1062 | ||
1063 | if (data[IFLA_GRE_ENCAP_SPORT]) { | |
1064 | ret = true; | |
3e97fa70 | 1065 | ipencap->sport = nla_get_be16(data[IFLA_GRE_ENCAP_SPORT]); |
4565e991 TH |
1066 | } |
1067 | ||
1068 | if (data[IFLA_GRE_ENCAP_DPORT]) { | |
1069 | ret = true; | |
3e97fa70 | 1070 | ipencap->dport = nla_get_be16(data[IFLA_GRE_ENCAP_DPORT]); |
4565e991 TH |
1071 | } |
1072 | ||
1073 | return ret; | |
1074 | } | |
1075 | ||
c5441932 | 1076 | static int gre_tap_init(struct net_device *dev) |
e1a80002 | 1077 | { |
c5441932 | 1078 | __gre_tunnel_init(dev); |
bec94d43 | 1079 | dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; |
e1a80002 | 1080 | |
c5441932 | 1081 | return ip_tunnel_init(dev); |
e1a80002 HX |
1082 | } |
1083 | ||
c5441932 PS |
1084 | static const struct net_device_ops gre_tap_netdev_ops = { |
1085 | .ndo_init = gre_tap_init, | |
1086 | .ndo_uninit = ip_tunnel_uninit, | |
1087 | .ndo_start_xmit = gre_tap_xmit, | |
b8c26a33 SH |
1088 | .ndo_set_mac_address = eth_mac_addr, |
1089 | .ndo_validate_addr = eth_validate_addr, | |
c5441932 PS |
1090 | .ndo_change_mtu = ip_tunnel_change_mtu, |
1091 | .ndo_get_stats64 = ip_tunnel_get_stats64, | |
1e99584b | 1092 | .ndo_get_iflink = ip_tunnel_get_iflink, |
fc4099f1 | 1093 | .ndo_fill_metadata_dst = gre_fill_metadata_dst, |
b8c26a33 SH |
1094 | }; |
1095 | ||
e1a80002 HX |
1096 | static void ipgre_tap_setup(struct net_device *dev) |
1097 | { | |
e1a80002 | 1098 | ether_setup(dev); |
d13b161c JB |
1099 | dev->netdev_ops = &gre_tap_netdev_ops; |
1100 | dev->priv_flags &= ~IFF_TX_SKB_SHARING; | |
1101 | dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; | |
c5441932 | 1102 | ip_tunnel_setup(dev, gre_tap_net_id); |
e1a80002 HX |
1103 | } |
1104 | ||
c5441932 PS |
1105 | static int ipgre_newlink(struct net *src_net, struct net_device *dev, |
1106 | struct nlattr *tb[], struct nlattr *data[]) | |
c19e654d | 1107 | { |
c5441932 | 1108 | struct ip_tunnel_parm p; |
4565e991 TH |
1109 | struct ip_tunnel_encap ipencap; |
1110 | ||
1111 | if (ipgre_netlink_encap_parms(data, &ipencap)) { | |
1112 | struct ip_tunnel *t = netdev_priv(dev); | |
1113 | int err = ip_tunnel_encap_setup(t, &ipencap); | |
1114 | ||
1115 | if (err < 0) | |
1116 | return err; | |
1117 | } | |
c19e654d | 1118 | |
2e15ea39 | 1119 | ipgre_netlink_parms(dev, data, tb, &p); |
c5441932 | 1120 | return ip_tunnel_newlink(dev, tb, &p); |
c19e654d HX |
1121 | } |
1122 | ||
1123 | static int ipgre_changelink(struct net_device *dev, struct nlattr *tb[], | |
1124 | struct nlattr *data[]) | |
1125 | { | |
c19e654d | 1126 | struct ip_tunnel_parm p; |
4565e991 TH |
1127 | struct ip_tunnel_encap ipencap; |
1128 | ||
1129 | if (ipgre_netlink_encap_parms(data, &ipencap)) { | |
1130 | struct ip_tunnel *t = netdev_priv(dev); | |
1131 | int err = ip_tunnel_encap_setup(t, &ipencap); | |
1132 | ||
1133 | if (err < 0) | |
1134 | return err; | |
1135 | } | |
c19e654d | 1136 | |
2e15ea39 | 1137 | ipgre_netlink_parms(dev, data, tb, &p); |
c5441932 | 1138 | return ip_tunnel_changelink(dev, tb, &p); |
c19e654d HX |
1139 | } |
1140 | ||
1141 | static size_t ipgre_get_size(const struct net_device *dev) | |
1142 | { | |
1143 | return | |
1144 | /* IFLA_GRE_LINK */ | |
1145 | nla_total_size(4) + | |
1146 | /* IFLA_GRE_IFLAGS */ | |
1147 | nla_total_size(2) + | |
1148 | /* IFLA_GRE_OFLAGS */ | |
1149 | nla_total_size(2) + | |
1150 | /* IFLA_GRE_IKEY */ | |
1151 | nla_total_size(4) + | |
1152 | /* IFLA_GRE_OKEY */ | |
1153 | nla_total_size(4) + | |
1154 | /* IFLA_GRE_LOCAL */ | |
1155 | nla_total_size(4) + | |
1156 | /* IFLA_GRE_REMOTE */ | |
1157 | nla_total_size(4) + | |
1158 | /* IFLA_GRE_TTL */ | |
1159 | nla_total_size(1) + | |
1160 | /* IFLA_GRE_TOS */ | |
1161 | nla_total_size(1) + | |
1162 | /* IFLA_GRE_PMTUDISC */ | |
1163 | nla_total_size(1) + | |
4565e991 TH |
1164 | /* IFLA_GRE_ENCAP_TYPE */ |
1165 | nla_total_size(2) + | |
1166 | /* IFLA_GRE_ENCAP_FLAGS */ | |
1167 | nla_total_size(2) + | |
1168 | /* IFLA_GRE_ENCAP_SPORT */ | |
1169 | nla_total_size(2) + | |
1170 | /* IFLA_GRE_ENCAP_DPORT */ | |
1171 | nla_total_size(2) + | |
2e15ea39 PS |
1172 | /* IFLA_GRE_COLLECT_METADATA */ |
1173 | nla_total_size(0) + | |
c19e654d HX |
1174 | 0; |
1175 | } | |
1176 | ||
1177 | static int ipgre_fill_info(struct sk_buff *skb, const struct net_device *dev) | |
1178 | { | |
1179 | struct ip_tunnel *t = netdev_priv(dev); | |
1180 | struct ip_tunnel_parm *p = &t->parms; | |
1181 | ||
f3756b79 | 1182 | if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) || |
c5441932 PS |
1183 | nla_put_be16(skb, IFLA_GRE_IFLAGS, tnl_flags_to_gre_flags(p->i_flags)) || |
1184 | nla_put_be16(skb, IFLA_GRE_OFLAGS, tnl_flags_to_gre_flags(p->o_flags)) || | |
f3756b79 DM |
1185 | nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) || |
1186 | nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) || | |
930345ea JB |
1187 | nla_put_in_addr(skb, IFLA_GRE_LOCAL, p->iph.saddr) || |
1188 | nla_put_in_addr(skb, IFLA_GRE_REMOTE, p->iph.daddr) || | |
f3756b79 DM |
1189 | nla_put_u8(skb, IFLA_GRE_TTL, p->iph.ttl) || |
1190 | nla_put_u8(skb, IFLA_GRE_TOS, p->iph.tos) || | |
1191 | nla_put_u8(skb, IFLA_GRE_PMTUDISC, | |
1192 | !!(p->iph.frag_off & htons(IP_DF)))) | |
1193 | goto nla_put_failure; | |
4565e991 TH |
1194 | |
1195 | if (nla_put_u16(skb, IFLA_GRE_ENCAP_TYPE, | |
1196 | t->encap.type) || | |
3e97fa70 SD |
1197 | nla_put_be16(skb, IFLA_GRE_ENCAP_SPORT, |
1198 | t->encap.sport) || | |
1199 | nla_put_be16(skb, IFLA_GRE_ENCAP_DPORT, | |
1200 | t->encap.dport) || | |
4565e991 | 1201 | nla_put_u16(skb, IFLA_GRE_ENCAP_FLAGS, |
e1b2cb65 | 1202 | t->encap.flags)) |
4565e991 TH |
1203 | goto nla_put_failure; |
1204 | ||
2e15ea39 PS |
1205 | if (t->collect_md) { |
1206 | if (nla_put_flag(skb, IFLA_GRE_COLLECT_METADATA)) | |
1207 | goto nla_put_failure; | |
1208 | } | |
1209 | ||
c19e654d HX |
1210 | return 0; |
1211 | ||
1212 | nla_put_failure: | |
1213 | return -EMSGSIZE; | |
1214 | } | |
1215 | ||
1216 | static const struct nla_policy ipgre_policy[IFLA_GRE_MAX + 1] = { | |
1217 | [IFLA_GRE_LINK] = { .type = NLA_U32 }, | |
1218 | [IFLA_GRE_IFLAGS] = { .type = NLA_U16 }, | |
1219 | [IFLA_GRE_OFLAGS] = { .type = NLA_U16 }, | |
1220 | [IFLA_GRE_IKEY] = { .type = NLA_U32 }, | |
1221 | [IFLA_GRE_OKEY] = { .type = NLA_U32 }, | |
4d74f8ba PM |
1222 | [IFLA_GRE_LOCAL] = { .len = FIELD_SIZEOF(struct iphdr, saddr) }, |
1223 | [IFLA_GRE_REMOTE] = { .len = FIELD_SIZEOF(struct iphdr, daddr) }, | |
c19e654d HX |
1224 | [IFLA_GRE_TTL] = { .type = NLA_U8 }, |
1225 | [IFLA_GRE_TOS] = { .type = NLA_U8 }, | |
1226 | [IFLA_GRE_PMTUDISC] = { .type = NLA_U8 }, | |
4565e991 TH |
1227 | [IFLA_GRE_ENCAP_TYPE] = { .type = NLA_U16 }, |
1228 | [IFLA_GRE_ENCAP_FLAGS] = { .type = NLA_U16 }, | |
1229 | [IFLA_GRE_ENCAP_SPORT] = { .type = NLA_U16 }, | |
1230 | [IFLA_GRE_ENCAP_DPORT] = { .type = NLA_U16 }, | |
2e15ea39 | 1231 | [IFLA_GRE_COLLECT_METADATA] = { .type = NLA_FLAG }, |
c19e654d HX |
1232 | }; |
1233 | ||
1234 | static struct rtnl_link_ops ipgre_link_ops __read_mostly = { | |
1235 | .kind = "gre", | |
1236 | .maxtype = IFLA_GRE_MAX, | |
1237 | .policy = ipgre_policy, | |
1238 | .priv_size = sizeof(struct ip_tunnel), | |
1239 | .setup = ipgre_tunnel_setup, | |
1240 | .validate = ipgre_tunnel_validate, | |
1241 | .newlink = ipgre_newlink, | |
1242 | .changelink = ipgre_changelink, | |
c5441932 | 1243 | .dellink = ip_tunnel_dellink, |
c19e654d HX |
1244 | .get_size = ipgre_get_size, |
1245 | .fill_info = ipgre_fill_info, | |
1728d4fa | 1246 | .get_link_net = ip_tunnel_get_link_net, |
c19e654d HX |
1247 | }; |
1248 | ||
e1a80002 HX |
1249 | static struct rtnl_link_ops ipgre_tap_ops __read_mostly = { |
1250 | .kind = "gretap", | |
1251 | .maxtype = IFLA_GRE_MAX, | |
1252 | .policy = ipgre_policy, | |
1253 | .priv_size = sizeof(struct ip_tunnel), | |
1254 | .setup = ipgre_tap_setup, | |
1255 | .validate = ipgre_tap_validate, | |
1256 | .newlink = ipgre_newlink, | |
1257 | .changelink = ipgre_changelink, | |
c5441932 | 1258 | .dellink = ip_tunnel_dellink, |
e1a80002 HX |
1259 | .get_size = ipgre_get_size, |
1260 | .fill_info = ipgre_fill_info, | |
1728d4fa | 1261 | .get_link_net = ip_tunnel_get_link_net, |
e1a80002 HX |
1262 | }; |
1263 | ||
b2acd1dc PS |
1264 | struct net_device *gretap_fb_dev_create(struct net *net, const char *name, |
1265 | u8 name_assign_type) | |
1266 | { | |
1267 | struct nlattr *tb[IFLA_MAX + 1]; | |
1268 | struct net_device *dev; | |
1269 | struct ip_tunnel *t; | |
1270 | int err; | |
1271 | ||
1272 | memset(&tb, 0, sizeof(tb)); | |
1273 | ||
1274 | dev = rtnl_create_link(net, name, name_assign_type, | |
1275 | &ipgre_tap_ops, tb); | |
1276 | if (IS_ERR(dev)) | |
1277 | return dev; | |
1278 | ||
1279 | /* Configure flow based GRE device. */ | |
1280 | t = netdev_priv(dev); | |
1281 | t->collect_md = true; | |
1282 | ||
1283 | err = ipgre_newlink(net, dev, tb, NULL); | |
1284 | if (err < 0) | |
1285 | goto out; | |
7e059158 DW |
1286 | |
1287 | /* openvswitch users expect packet sizes to be unrestricted, | |
1288 | * so set the largest MTU we can. | |
1289 | */ | |
1290 | err = __ip_tunnel_change_mtu(dev, IP_MAX_MTU, false); | |
1291 | if (err) | |
1292 | goto out; | |
1293 | ||
b2acd1dc PS |
1294 | return dev; |
1295 | out: | |
1296 | free_netdev(dev); | |
1297 | return ERR_PTR(err); | |
1298 | } | |
1299 | EXPORT_SYMBOL_GPL(gretap_fb_dev_create); | |
1300 | ||
c5441932 PS |
1301 | static int __net_init ipgre_tap_init_net(struct net *net) |
1302 | { | |
2e15ea39 | 1303 | return ip_tunnel_init_net(net, gre_tap_net_id, &ipgre_tap_ops, "gretap0"); |
c5441932 PS |
1304 | } |
1305 | ||
1306 | static void __net_exit ipgre_tap_exit_net(struct net *net) | |
1307 | { | |
1308 | struct ip_tunnel_net *itn = net_generic(net, gre_tap_net_id); | |
6c742e71 | 1309 | ip_tunnel_delete_net(itn, &ipgre_tap_ops); |
c5441932 PS |
1310 | } |
1311 | ||
1312 | static struct pernet_operations ipgre_tap_net_ops = { | |
1313 | .init = ipgre_tap_init_net, | |
1314 | .exit = ipgre_tap_exit_net, | |
1315 | .id = &gre_tap_net_id, | |
1316 | .size = sizeof(struct ip_tunnel_net), | |
1317 | }; | |
1da177e4 LT |
1318 | |
1319 | static int __init ipgre_init(void) | |
1320 | { | |
1321 | int err; | |
1322 | ||
058bd4d2 | 1323 | pr_info("GRE over IPv4 tunneling driver\n"); |
1da177e4 | 1324 | |
cfb8fbf2 | 1325 | err = register_pernet_device(&ipgre_net_ops); |
59a4c759 | 1326 | if (err < 0) |
c2892f02 AD |
1327 | return err; |
1328 | ||
c5441932 PS |
1329 | err = register_pernet_device(&ipgre_tap_net_ops); |
1330 | if (err < 0) | |
1331 | goto pnet_tap_faied; | |
1332 | ||
9f57c67c | 1333 | err = gre_add_protocol(&ipgre_protocol, GREPROTO_CISCO); |
c2892f02 | 1334 | if (err < 0) { |
058bd4d2 | 1335 | pr_info("%s: can't add protocol\n", __func__); |
c2892f02 AD |
1336 | goto add_proto_failed; |
1337 | } | |
7daa0004 | 1338 | |
c19e654d HX |
1339 | err = rtnl_link_register(&ipgre_link_ops); |
1340 | if (err < 0) | |
1341 | goto rtnl_link_failed; | |
1342 | ||
e1a80002 HX |
1343 | err = rtnl_link_register(&ipgre_tap_ops); |
1344 | if (err < 0) | |
1345 | goto tap_ops_failed; | |
1346 | ||
c5441932 | 1347 | return 0; |
c19e654d | 1348 | |
e1a80002 HX |
1349 | tap_ops_failed: |
1350 | rtnl_link_unregister(&ipgre_link_ops); | |
c19e654d | 1351 | rtnl_link_failed: |
9f57c67c | 1352 | gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO); |
c2892f02 | 1353 | add_proto_failed: |
c5441932 PS |
1354 | unregister_pernet_device(&ipgre_tap_net_ops); |
1355 | pnet_tap_faied: | |
c2892f02 | 1356 | unregister_pernet_device(&ipgre_net_ops); |
c5441932 | 1357 | return err; |
1da177e4 LT |
1358 | } |
1359 | ||
db44575f | 1360 | static void __exit ipgre_fini(void) |
1da177e4 | 1361 | { |
e1a80002 | 1362 | rtnl_link_unregister(&ipgre_tap_ops); |
c19e654d | 1363 | rtnl_link_unregister(&ipgre_link_ops); |
9f57c67c | 1364 | gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO); |
c5441932 | 1365 | unregister_pernet_device(&ipgre_tap_net_ops); |
c2892f02 | 1366 | unregister_pernet_device(&ipgre_net_ops); |
1da177e4 LT |
1367 | } |
1368 | ||
1369 | module_init(ipgre_init); | |
1370 | module_exit(ipgre_fini); | |
1371 | MODULE_LICENSE("GPL"); | |
4d74f8ba PM |
1372 | MODULE_ALIAS_RTNL_LINK("gre"); |
1373 | MODULE_ALIAS_RTNL_LINK("gretap"); | |
8909c9ad | 1374 | MODULE_ALIAS_NETDEV("gre0"); |
c5441932 | 1375 | MODULE_ALIAS_NETDEV("gretap0"); |