Commit | Line | Data |
---|---|---|
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> | |
27 | #include <linux/mroute.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> | |
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> |
1da177e4 | 50 | |
dfd56b8b | 51 | #if IS_ENABLED(CONFIG_IPV6) |
1da177e4 LT |
52 | #include <net/ipv6.h> |
53 | #include <net/ip6_fib.h> | |
54 | #include <net/ip6_route.h> | |
55 | #endif | |
56 | ||
57 | /* | |
58 | Problems & solutions | |
59 | -------------------- | |
60 | ||
61 | 1. The most important issue is detecting local dead loops. | |
62 | They would cause complete host lockup in transmit, which | |
63 | would be "resolved" by stack overflow or, if queueing is enabled, | |
64 | with infinite looping in net_bh. | |
65 | ||
66 | We cannot track such dead loops during route installation, | |
67 | it is infeasible task. The most general solutions would be | |
68 | to keep skb->encapsulation counter (sort of local ttl), | |
6d0722a2 | 69 | and silently drop packet when it expires. It is a good |
bff52857 | 70 | solution, but it supposes maintaining new variable in ALL |
1da177e4 LT |
71 | skb, even if no tunneling is used. |
72 | ||
6d0722a2 ED |
73 | Current solution: xmit_recursion breaks dead loops. This is a percpu |
74 | counter, since when we enter the first ndo_xmit(), cpu migration is | |
75 | forbidden. We force an exit if this counter reaches RECURSION_LIMIT | |
1da177e4 LT |
76 | |
77 | 2. Networking dead loops would not kill routers, but would really | |
78 | kill network. IP hop limit plays role of "t->recursion" in this case, | |
79 | if we copy it from packet being encapsulated to upper header. | |
80 | It is very good solution, but it introduces two problems: | |
81 | ||
82 | - Routing protocols, using packets with ttl=1 (OSPF, RIP2), | |
83 | do not work over tunnels. | |
84 | - traceroute does not work. I planned to relay ICMP from tunnel, | |
85 | so that this problem would be solved and traceroute output | |
86 | would even more informative. This idea appeared to be wrong: | |
87 | only Linux complies to rfc1812 now (yes, guys, Linux is the only | |
88 | true router now :-)), all routers (at least, in neighbourhood of mine) | |
89 | return only 8 bytes of payload. It is the end. | |
90 | ||
91 | Hence, if we want that OSPF worked or traceroute said something reasonable, | |
92 | we should search for another solution. | |
93 | ||
94 | One of them is to parse packet trying to detect inner encapsulation | |
95 | made by our node. It is difficult or even impossible, especially, | |
bff52857 | 96 | taking into account fragmentation. TO be short, ttl is not solution at all. |
1da177e4 LT |
97 | |
98 | Current solution: The solution was UNEXPECTEDLY SIMPLE. | |
99 | We force DF flag on tunnels with preconfigured hop limit, | |
100 | that is ALL. :-) Well, it does not remove the problem completely, | |
101 | but exponential growth of network traffic is changed to linear | |
102 | (branches, that exceed pmtu are pruned) and tunnel mtu | |
bff52857 | 103 | rapidly degrades to value <68, where looping stops. |
1da177e4 LT |
104 | Yes, it is not good if there exists a router in the loop, |
105 | which does not force DF, even when encapsulating packets have DF set. | |
106 | But it is not our problem! Nobody could accuse us, we made | |
107 | all that we could make. Even if it is your gated who injected | |
108 | fatal route to network, even if it were you who configured | |
109 | fatal static route: you are innocent. :-) | |
110 | ||
1da177e4 LT |
111 | Alexey Kuznetsov. |
112 | */ | |
113 | ||
eccc1bb8 | 114 | static bool log_ecn_error = true; |
115 | module_param(log_ecn_error, bool, 0644); | |
116 | MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN"); | |
117 | ||
c19e654d | 118 | static struct rtnl_link_ops ipgre_link_ops __read_mostly; |
1da177e4 | 119 | static int ipgre_tunnel_init(struct net_device *dev); |
eb8ce741 | 120 | |
f99189b1 | 121 | static int ipgre_net_id __read_mostly; |
c5441932 | 122 | static int gre_tap_net_id __read_mostly; |
1da177e4 | 123 | |
bda7bb46 PS |
124 | static int ipgre_err(struct sk_buff *skb, u32 info, |
125 | const struct tnl_ptk_info *tpi) | |
1da177e4 | 126 | { |
1da177e4 | 127 | |
c5441932 PS |
128 | /* All the routers (except for Linux) return only |
129 | 8 bytes of packet payload. It means, that precise relaying of | |
130 | ICMP in the real Internet is absolutely infeasible. | |
1da177e4 | 131 | |
c5441932 PS |
132 | Moreover, Cisco "wise men" put GRE key to the third word |
133 | in GRE header. It makes impossible maintaining even soft | |
134 | state for keyed GRE tunnels with enabled checksum. Tell | |
135 | them "thank you". | |
1da177e4 | 136 | |
c5441932 PS |
137 | Well, I wonder, rfc1812 was written by Cisco employee, |
138 | what the hell these idiots break standards established | |
139 | by themselves??? | |
140 | */ | |
141 | struct net *net = dev_net(skb->dev); | |
142 | struct ip_tunnel_net *itn; | |
96f5a846 | 143 | const struct iphdr *iph; |
88c7664f ACM |
144 | const int type = icmp_hdr(skb)->type; |
145 | const int code = icmp_hdr(skb)->code; | |
1da177e4 | 146 | struct ip_tunnel *t; |
1da177e4 | 147 | |
1da177e4 LT |
148 | switch (type) { |
149 | default: | |
150 | case ICMP_PARAMETERPROB: | |
bda7bb46 | 151 | return PACKET_RCVD; |
1da177e4 LT |
152 | |
153 | case ICMP_DEST_UNREACH: | |
154 | switch (code) { | |
155 | case ICMP_SR_FAILED: | |
156 | case ICMP_PORT_UNREACH: | |
157 | /* Impossible event. */ | |
bda7bb46 | 158 | return PACKET_RCVD; |
1da177e4 LT |
159 | default: |
160 | /* All others are translated to HOST_UNREACH. | |
161 | rfc2003 contains "deep thoughts" about NET_UNREACH, | |
162 | I believe they are just ether pollution. --ANK | |
163 | */ | |
164 | break; | |
165 | } | |
166 | break; | |
167 | case ICMP_TIME_EXCEEDED: | |
168 | if (code != ICMP_EXC_TTL) | |
bda7bb46 | 169 | return PACKET_RCVD; |
1da177e4 | 170 | break; |
55be7a9c DM |
171 | |
172 | case ICMP_REDIRECT: | |
173 | break; | |
1da177e4 LT |
174 | } |
175 | ||
bda7bb46 | 176 | if (tpi->proto == htons(ETH_P_TEB)) |
c5441932 PS |
177 | itn = net_generic(net, gre_tap_net_id); |
178 | else | |
179 | itn = net_generic(net, ipgre_net_id); | |
180 | ||
96f5a846 | 181 | iph = (const struct iphdr *)skb->data; |
bda7bb46 PS |
182 | t = ip_tunnel_lookup(itn, skb->dev->ifindex, tpi->flags, |
183 | iph->daddr, iph->saddr, tpi->key); | |
d2083287 | 184 | |
36393395 | 185 | if (t == NULL) |
bda7bb46 | 186 | return PACKET_REJECT; |
36393395 | 187 | |
36393395 | 188 | if (t->parms.iph.daddr == 0 || |
f97c1e0c | 189 | ipv4_is_multicast(t->parms.iph.daddr)) |
bda7bb46 | 190 | return PACKET_RCVD; |
1da177e4 LT |
191 | |
192 | if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED) | |
bda7bb46 | 193 | return PACKET_RCVD; |
1da177e4 | 194 | |
da6185d8 | 195 | if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO)) |
1da177e4 LT |
196 | t->err_count++; |
197 | else | |
198 | t->err_count = 1; | |
199 | t->err_time = jiffies; | |
bda7bb46 | 200 | return PACKET_RCVD; |
1da177e4 LT |
201 | } |
202 | ||
bda7bb46 | 203 | static int ipgre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi) |
1da177e4 | 204 | { |
c5441932 PS |
205 | struct net *net = dev_net(skb->dev); |
206 | struct ip_tunnel_net *itn; | |
b71d1d42 | 207 | const struct iphdr *iph; |
1da177e4 | 208 | struct ip_tunnel *tunnel; |
1da177e4 | 209 | |
bda7bb46 | 210 | if (tpi->proto == htons(ETH_P_TEB)) |
c5441932 PS |
211 | itn = net_generic(net, gre_tap_net_id); |
212 | else | |
213 | itn = net_generic(net, ipgre_net_id); | |
1da177e4 | 214 | |
c5441932 | 215 | iph = ip_hdr(skb); |
bda7bb46 PS |
216 | tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, tpi->flags, |
217 | iph->saddr, iph->daddr, tpi->key); | |
e1a80002 | 218 | |
d2083287 | 219 | if (tunnel) { |
bda7bb46 PS |
220 | ip_tunnel_rcv(tunnel, skb, tpi, log_ecn_error); |
221 | return PACKET_RCVD; | |
1da177e4 | 222 | } |
bda7bb46 | 223 | return PACKET_REJECT; |
1da177e4 LT |
224 | } |
225 | ||
c5441932 PS |
226 | static void __gre_xmit(struct sk_buff *skb, struct net_device *dev, |
227 | const struct iphdr *tnl_params, | |
228 | __be16 proto) | |
229 | { | |
230 | struct ip_tunnel *tunnel = netdev_priv(dev); | |
231 | struct tnl_ptk_info tpi; | |
1da177e4 | 232 | |
c5441932 PS |
233 | tpi.flags = tunnel->parms.o_flags; |
234 | tpi.proto = proto; | |
235 | tpi.key = tunnel->parms.o_key; | |
236 | if (tunnel->parms.o_flags & TUNNEL_SEQ) | |
237 | tunnel->o_seqno++; | |
238 | tpi.seq = htonl(tunnel->o_seqno); | |
1da177e4 | 239 | |
c5441932 | 240 | /* Push GRE header. */ |
752f36da | 241 | gre_build_header(skb, &tpi, tunnel->hlen); |
1da177e4 | 242 | |
bf3d6a8f | 243 | ip_tunnel_xmit(skb, dev, tnl_params, tnl_params->protocol); |
c5441932 | 244 | } |
1da177e4 | 245 | |
c5441932 PS |
246 | static netdev_tx_t ipgre_xmit(struct sk_buff *skb, |
247 | struct net_device *dev) | |
248 | { | |
249 | struct ip_tunnel *tunnel = netdev_priv(dev); | |
250 | const struct iphdr *tnl_params; | |
1da177e4 | 251 | |
45f2e997 | 252 | skb = gre_handle_offloads(skb, !!(tunnel->parms.o_flags&TUNNEL_CSUM)); |
c5441932 PS |
253 | if (IS_ERR(skb)) |
254 | goto out; | |
1da177e4 | 255 | |
c5441932 PS |
256 | if (dev->header_ops) { |
257 | /* Need space for new headers */ | |
258 | if (skb_cow_head(skb, dev->needed_headroom - | |
2bac7cb3 | 259 | (tunnel->hlen + sizeof(struct iphdr)))) |
c5441932 | 260 | goto free_skb; |
1da177e4 | 261 | |
c5441932 | 262 | tnl_params = (const struct iphdr *)skb->data; |
1da177e4 | 263 | |
c5441932 PS |
264 | /* Pull skb since ip_tunnel_xmit() needs skb->data pointing |
265 | * to gre header. | |
266 | */ | |
267 | skb_pull(skb, tunnel->hlen + sizeof(struct iphdr)); | |
268 | } else { | |
269 | if (skb_cow_head(skb, dev->needed_headroom)) | |
270 | goto free_skb; | |
1da177e4 | 271 | |
c5441932 | 272 | tnl_params = &tunnel->parms.iph; |
1da177e4 LT |
273 | } |
274 | ||
c5441932 PS |
275 | __gre_xmit(skb, dev, tnl_params, skb->protocol); |
276 | ||
6ed10654 | 277 | return NETDEV_TX_OK; |
1da177e4 | 278 | |
c5441932 | 279 | free_skb: |
1da177e4 | 280 | dev_kfree_skb(skb); |
c5441932 PS |
281 | out: |
282 | dev->stats.tx_dropped++; | |
6ed10654 | 283 | return NETDEV_TX_OK; |
1da177e4 LT |
284 | } |
285 | ||
c5441932 PS |
286 | static netdev_tx_t gre_tap_xmit(struct sk_buff *skb, |
287 | struct net_device *dev) | |
ee34c1eb | 288 | { |
c5441932 | 289 | struct ip_tunnel *tunnel = netdev_priv(dev); |
ee34c1eb | 290 | |
45f2e997 | 291 | skb = gre_handle_offloads(skb, !!(tunnel->parms.o_flags&TUNNEL_CSUM)); |
c5441932 PS |
292 | if (IS_ERR(skb)) |
293 | goto out; | |
ee34c1eb | 294 | |
c5441932 PS |
295 | if (skb_cow_head(skb, dev->needed_headroom)) |
296 | goto free_skb; | |
42aa9162 | 297 | |
c5441932 | 298 | __gre_xmit(skb, dev, &tunnel->parms.iph, htons(ETH_P_TEB)); |
42aa9162 | 299 | |
c5441932 | 300 | return NETDEV_TX_OK; |
ee34c1eb | 301 | |
c5441932 PS |
302 | free_skb: |
303 | dev_kfree_skb(skb); | |
304 | out: | |
305 | dev->stats.tx_dropped++; | |
306 | return NETDEV_TX_OK; | |
ee34c1eb MS |
307 | } |
308 | ||
c5441932 PS |
309 | static int ipgre_tunnel_ioctl(struct net_device *dev, |
310 | struct ifreq *ifr, int cmd) | |
1da177e4 LT |
311 | { |
312 | int err = 0; | |
313 | struct ip_tunnel_parm p; | |
1da177e4 | 314 | |
c5441932 PS |
315 | if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) |
316 | return -EFAULT; | |
6c734fb8 CW |
317 | if (cmd == SIOCADDTUNNEL || cmd == SIOCCHGTUNNEL) { |
318 | if (p.iph.version != 4 || p.iph.protocol != IPPROTO_GRE || | |
319 | p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF)) || | |
320 | ((p.i_flags|p.o_flags)&(GRE_VERSION|GRE_ROUTING))) | |
321 | return -EINVAL; | |
1da177e4 | 322 | } |
c5441932 PS |
323 | p.i_flags = gre_flags_to_tnl_flags(p.i_flags); |
324 | p.o_flags = gre_flags_to_tnl_flags(p.o_flags); | |
1da177e4 | 325 | |
c5441932 PS |
326 | err = ip_tunnel_ioctl(dev, &p, cmd); |
327 | if (err) | |
328 | return err; | |
1da177e4 | 329 | |
c5441932 PS |
330 | p.i_flags = tnl_flags_to_gre_flags(p.i_flags); |
331 | p.o_flags = tnl_flags_to_gre_flags(p.o_flags); | |
332 | ||
333 | if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) | |
334 | return -EFAULT; | |
1da177e4 LT |
335 | return 0; |
336 | } | |
337 | ||
1da177e4 LT |
338 | /* Nice toy. Unfortunately, useless in real life :-) |
339 | It allows to construct virtual multiprotocol broadcast "LAN" | |
340 | over the Internet, provided multicast routing is tuned. | |
341 | ||
342 | ||
343 | I have no idea was this bicycle invented before me, | |
344 | so that I had to set ARPHRD_IPGRE to a random value. | |
345 | I have an impression, that Cisco could make something similar, | |
346 | but this feature is apparently missing in IOS<=11.2(8). | |
e905a9ed | 347 | |
1da177e4 LT |
348 | I set up 10.66.66/24 and fec0:6666:6666::0/96 as virtual networks |
349 | with broadcast 224.66.66.66. If you have access to mbone, play with me :-) | |
350 | ||
351 | ping -t 255 224.66.66.66 | |
352 | ||
353 | If nobody answers, mbone does not work. | |
354 | ||
355 | ip tunnel add Universe mode gre remote 224.66.66.66 local <Your_real_addr> ttl 255 | |
356 | ip addr add 10.66.66.<somewhat>/24 dev Universe | |
357 | ifconfig Universe up | |
358 | ifconfig Universe add fe80::<Your_real_addr>/10 | |
359 | ifconfig Universe add fec0:6666:6666::<Your_real_addr>/96 | |
360 | ftp 10.66.66.66 | |
361 | ... | |
362 | ftp fec0:6666:6666::193.233.7.65 | |
363 | ... | |
1da177e4 | 364 | */ |
3b04ddde SH |
365 | static int ipgre_header(struct sk_buff *skb, struct net_device *dev, |
366 | unsigned short type, | |
1507850b | 367 | const void *daddr, const void *saddr, unsigned int len) |
1da177e4 | 368 | { |
2941a486 | 369 | struct ip_tunnel *t = netdev_priv(dev); |
c5441932 PS |
370 | struct iphdr *iph; |
371 | struct gre_base_hdr *greh; | |
1da177e4 | 372 | |
c5441932 PS |
373 | iph = (struct iphdr *)skb_push(skb, t->hlen + sizeof(*iph)); |
374 | greh = (struct gre_base_hdr *)(iph+1); | |
375 | greh->flags = tnl_flags_to_gre_flags(t->parms.o_flags); | |
376 | greh->protocol = htons(type); | |
1da177e4 | 377 | |
c5441932 | 378 | memcpy(iph, &t->parms.iph, sizeof(struct iphdr)); |
e905a9ed | 379 | |
c5441932 | 380 | /* Set the source hardware address. */ |
1da177e4 LT |
381 | if (saddr) |
382 | memcpy(&iph->saddr, saddr, 4); | |
6d55cb91 | 383 | if (daddr) |
1da177e4 | 384 | memcpy(&iph->daddr, daddr, 4); |
6d55cb91 | 385 | if (iph->daddr) |
77a482bd | 386 | return t->hlen + sizeof(*iph); |
e905a9ed | 387 | |
c5441932 | 388 | return -(t->hlen + sizeof(*iph)); |
1da177e4 LT |
389 | } |
390 | ||
6a5f44d7 TT |
391 | static int ipgre_header_parse(const struct sk_buff *skb, unsigned char *haddr) |
392 | { | |
b71d1d42 | 393 | const struct iphdr *iph = (const struct iphdr *) skb_mac_header(skb); |
6a5f44d7 TT |
394 | memcpy(haddr, &iph->saddr, 4); |
395 | return 4; | |
396 | } | |
397 | ||
3b04ddde SH |
398 | static const struct header_ops ipgre_header_ops = { |
399 | .create = ipgre_header, | |
6a5f44d7 | 400 | .parse = ipgre_header_parse, |
3b04ddde SH |
401 | }; |
402 | ||
6a5f44d7 | 403 | #ifdef CONFIG_NET_IPGRE_BROADCAST |
1da177e4 LT |
404 | static int ipgre_open(struct net_device *dev) |
405 | { | |
2941a486 | 406 | struct ip_tunnel *t = netdev_priv(dev); |
1da177e4 | 407 | |
f97c1e0c | 408 | if (ipv4_is_multicast(t->parms.iph.daddr)) { |
cbb1e85f DM |
409 | struct flowi4 fl4; |
410 | struct rtable *rt; | |
411 | ||
412 | rt = ip_route_output_gre(dev_net(dev), &fl4, | |
413 | t->parms.iph.daddr, | |
414 | t->parms.iph.saddr, | |
415 | t->parms.o_key, | |
416 | RT_TOS(t->parms.iph.tos), | |
417 | t->parms.link); | |
b23dd4fe | 418 | if (IS_ERR(rt)) |
1da177e4 | 419 | return -EADDRNOTAVAIL; |
d8d1f30b | 420 | dev = rt->dst.dev; |
1da177e4 | 421 | ip_rt_put(rt); |
e5ed6399 | 422 | if (__in_dev_get_rtnl(dev) == NULL) |
1da177e4 LT |
423 | return -EADDRNOTAVAIL; |
424 | t->mlink = dev->ifindex; | |
e5ed6399 | 425 | ip_mc_inc_group(__in_dev_get_rtnl(dev), t->parms.iph.daddr); |
1da177e4 LT |
426 | } |
427 | return 0; | |
428 | } | |
429 | ||
430 | static int ipgre_close(struct net_device *dev) | |
431 | { | |
2941a486 | 432 | struct ip_tunnel *t = netdev_priv(dev); |
b8c26a33 | 433 | |
f97c1e0c | 434 | if (ipv4_is_multicast(t->parms.iph.daddr) && t->mlink) { |
7fee0ca2 | 435 | struct in_device *in_dev; |
c346dca1 | 436 | in_dev = inetdev_by_index(dev_net(dev), t->mlink); |
8723e1b4 | 437 | if (in_dev) |
1da177e4 | 438 | ip_mc_dec_group(in_dev, t->parms.iph.daddr); |
1da177e4 LT |
439 | } |
440 | return 0; | |
441 | } | |
1da177e4 LT |
442 | #endif |
443 | ||
b8c26a33 SH |
444 | static const struct net_device_ops ipgre_netdev_ops = { |
445 | .ndo_init = ipgre_tunnel_init, | |
c5441932 | 446 | .ndo_uninit = ip_tunnel_uninit, |
b8c26a33 SH |
447 | #ifdef CONFIG_NET_IPGRE_BROADCAST |
448 | .ndo_open = ipgre_open, | |
449 | .ndo_stop = ipgre_close, | |
450 | #endif | |
c5441932 | 451 | .ndo_start_xmit = ipgre_xmit, |
b8c26a33 | 452 | .ndo_do_ioctl = ipgre_tunnel_ioctl, |
c5441932 PS |
453 | .ndo_change_mtu = ip_tunnel_change_mtu, |
454 | .ndo_get_stats64 = ip_tunnel_get_stats64, | |
b8c26a33 SH |
455 | }; |
456 | ||
6b78f16e ED |
457 | #define GRE_FEATURES (NETIF_F_SG | \ |
458 | NETIF_F_FRAGLIST | \ | |
459 | NETIF_F_HIGHDMA | \ | |
460 | NETIF_F_HW_CSUM) | |
461 | ||
1da177e4 LT |
462 | static void ipgre_tunnel_setup(struct net_device *dev) |
463 | { | |
b8c26a33 | 464 | dev->netdev_ops = &ipgre_netdev_ops; |
c5441932 PS |
465 | ip_tunnel_setup(dev, ipgre_net_id); |
466 | } | |
1da177e4 | 467 | |
c5441932 PS |
468 | static void __gre_tunnel_init(struct net_device *dev) |
469 | { | |
470 | struct ip_tunnel *tunnel; | |
471 | ||
472 | tunnel = netdev_priv(dev); | |
473 | tunnel->hlen = ip_gre_calc_hlen(tunnel->parms.o_flags); | |
474 | tunnel->parms.iph.protocol = IPPROTO_GRE; | |
475 | ||
476 | dev->needed_headroom = LL_MAX_HEADER + sizeof(struct iphdr) + 4; | |
46f25dff | 477 | dev->mtu = ETH_DATA_LEN - sizeof(struct iphdr) - 4; |
6b78f16e | 478 | |
c5441932 | 479 | dev->features |= NETIF_F_NETNS_LOCAL | GRE_FEATURES; |
6b78f16e | 480 | dev->hw_features |= GRE_FEATURES; |
c5441932 PS |
481 | |
482 | if (!(tunnel->parms.o_flags & TUNNEL_SEQ)) { | |
483 | /* TCP offload with GRE SEQ is not supported. */ | |
484 | dev->features |= NETIF_F_GSO_SOFTWARE; | |
485 | dev->hw_features |= NETIF_F_GSO_SOFTWARE; | |
486 | /* Can use a lockless transmit, unless we generate | |
487 | * output sequences | |
488 | */ | |
489 | dev->features |= NETIF_F_LLTX; | |
490 | } | |
1da177e4 LT |
491 | } |
492 | ||
493 | static int ipgre_tunnel_init(struct net_device *dev) | |
494 | { | |
c5441932 PS |
495 | struct ip_tunnel *tunnel = netdev_priv(dev); |
496 | struct iphdr *iph = &tunnel->parms.iph; | |
1da177e4 | 497 | |
c5441932 | 498 | __gre_tunnel_init(dev); |
1da177e4 | 499 | |
c5441932 PS |
500 | memcpy(dev->dev_addr, &iph->saddr, 4); |
501 | memcpy(dev->broadcast, &iph->daddr, 4); | |
1da177e4 | 502 | |
c5441932 PS |
503 | dev->type = ARPHRD_IPGRE; |
504 | dev->flags = IFF_NOARP; | |
505 | dev->priv_flags &= ~IFF_XMIT_DST_RELEASE; | |
506 | dev->addr_len = 4; | |
1da177e4 | 507 | |
1da177e4 | 508 | if (iph->daddr) { |
1da177e4 | 509 | #ifdef CONFIG_NET_IPGRE_BROADCAST |
f97c1e0c | 510 | if (ipv4_is_multicast(iph->daddr)) { |
1da177e4 LT |
511 | if (!iph->saddr) |
512 | return -EINVAL; | |
513 | dev->flags = IFF_BROADCAST; | |
3b04ddde | 514 | dev->header_ops = &ipgre_header_ops; |
1da177e4 LT |
515 | } |
516 | #endif | |
ee34c1eb | 517 | } else |
6a5f44d7 | 518 | dev->header_ops = &ipgre_header_ops; |
1da177e4 | 519 | |
c5441932 | 520 | return ip_tunnel_init(dev); |
1da177e4 LT |
521 | } |
522 | ||
bda7bb46 PS |
523 | static struct gre_cisco_protocol ipgre_protocol = { |
524 | .handler = ipgre_rcv, | |
525 | .err_handler = ipgre_err, | |
526 | .priority = 0, | |
1da177e4 LT |
527 | }; |
528 | ||
2c8c1e72 | 529 | static int __net_init ipgre_init_net(struct net *net) |
59a4c759 | 530 | { |
c5441932 | 531 | return ip_tunnel_init_net(net, ipgre_net_id, &ipgre_link_ops, NULL); |
59a4c759 PE |
532 | } |
533 | ||
2c8c1e72 | 534 | static void __net_exit ipgre_exit_net(struct net *net) |
59a4c759 | 535 | { |
c5441932 | 536 | struct ip_tunnel_net *itn = net_generic(net, ipgre_net_id); |
6c742e71 | 537 | ip_tunnel_delete_net(itn, &ipgre_link_ops); |
59a4c759 PE |
538 | } |
539 | ||
540 | static struct pernet_operations ipgre_net_ops = { | |
541 | .init = ipgre_init_net, | |
542 | .exit = ipgre_exit_net, | |
cfb8fbf2 | 543 | .id = &ipgre_net_id, |
c5441932 | 544 | .size = sizeof(struct ip_tunnel_net), |
59a4c759 | 545 | }; |
1da177e4 | 546 | |
c19e654d HX |
547 | static int ipgre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[]) |
548 | { | |
549 | __be16 flags; | |
550 | ||
551 | if (!data) | |
552 | return 0; | |
553 | ||
554 | flags = 0; | |
555 | if (data[IFLA_GRE_IFLAGS]) | |
556 | flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]); | |
557 | if (data[IFLA_GRE_OFLAGS]) | |
558 | flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]); | |
559 | if (flags & (GRE_VERSION|GRE_ROUTING)) | |
560 | return -EINVAL; | |
561 | ||
562 | return 0; | |
563 | } | |
564 | ||
e1a80002 HX |
565 | static int ipgre_tap_validate(struct nlattr *tb[], struct nlattr *data[]) |
566 | { | |
567 | __be32 daddr; | |
568 | ||
569 | if (tb[IFLA_ADDRESS]) { | |
570 | if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) | |
571 | return -EINVAL; | |
572 | if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) | |
573 | return -EADDRNOTAVAIL; | |
574 | } | |
575 | ||
576 | if (!data) | |
577 | goto out; | |
578 | ||
579 | if (data[IFLA_GRE_REMOTE]) { | |
580 | memcpy(&daddr, nla_data(data[IFLA_GRE_REMOTE]), 4); | |
581 | if (!daddr) | |
582 | return -EINVAL; | |
583 | } | |
584 | ||
585 | out: | |
586 | return ipgre_tunnel_validate(tb, data); | |
587 | } | |
588 | ||
c5441932 PS |
589 | static void ipgre_netlink_parms(struct nlattr *data[], struct nlattr *tb[], |
590 | struct ip_tunnel_parm *parms) | |
c19e654d | 591 | { |
7bb82d92 | 592 | memset(parms, 0, sizeof(*parms)); |
c19e654d HX |
593 | |
594 | parms->iph.protocol = IPPROTO_GRE; | |
595 | ||
596 | if (!data) | |
597 | return; | |
598 | ||
599 | if (data[IFLA_GRE_LINK]) | |
600 | parms->link = nla_get_u32(data[IFLA_GRE_LINK]); | |
601 | ||
602 | if (data[IFLA_GRE_IFLAGS]) | |
c5441932 | 603 | parms->i_flags = gre_flags_to_tnl_flags(nla_get_be16(data[IFLA_GRE_IFLAGS])); |
c19e654d HX |
604 | |
605 | if (data[IFLA_GRE_OFLAGS]) | |
c5441932 | 606 | parms->o_flags = gre_flags_to_tnl_flags(nla_get_be16(data[IFLA_GRE_OFLAGS])); |
c19e654d HX |
607 | |
608 | if (data[IFLA_GRE_IKEY]) | |
609 | parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]); | |
610 | ||
611 | if (data[IFLA_GRE_OKEY]) | |
612 | parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]); | |
613 | ||
614 | if (data[IFLA_GRE_LOCAL]) | |
4d74f8ba | 615 | parms->iph.saddr = nla_get_be32(data[IFLA_GRE_LOCAL]); |
c19e654d HX |
616 | |
617 | if (data[IFLA_GRE_REMOTE]) | |
4d74f8ba | 618 | parms->iph.daddr = nla_get_be32(data[IFLA_GRE_REMOTE]); |
c19e654d HX |
619 | |
620 | if (data[IFLA_GRE_TTL]) | |
621 | parms->iph.ttl = nla_get_u8(data[IFLA_GRE_TTL]); | |
622 | ||
623 | if (data[IFLA_GRE_TOS]) | |
624 | parms->iph.tos = nla_get_u8(data[IFLA_GRE_TOS]); | |
625 | ||
626 | if (!data[IFLA_GRE_PMTUDISC] || nla_get_u8(data[IFLA_GRE_PMTUDISC])) | |
627 | parms->iph.frag_off = htons(IP_DF); | |
628 | } | |
629 | ||
c5441932 | 630 | static int gre_tap_init(struct net_device *dev) |
e1a80002 | 631 | { |
c5441932 | 632 | __gre_tunnel_init(dev); |
e1a80002 | 633 | |
c5441932 | 634 | return ip_tunnel_init(dev); |
e1a80002 HX |
635 | } |
636 | ||
c5441932 PS |
637 | static const struct net_device_ops gre_tap_netdev_ops = { |
638 | .ndo_init = gre_tap_init, | |
639 | .ndo_uninit = ip_tunnel_uninit, | |
640 | .ndo_start_xmit = gre_tap_xmit, | |
b8c26a33 SH |
641 | .ndo_set_mac_address = eth_mac_addr, |
642 | .ndo_validate_addr = eth_validate_addr, | |
c5441932 PS |
643 | .ndo_change_mtu = ip_tunnel_change_mtu, |
644 | .ndo_get_stats64 = ip_tunnel_get_stats64, | |
b8c26a33 SH |
645 | }; |
646 | ||
e1a80002 HX |
647 | static void ipgre_tap_setup(struct net_device *dev) |
648 | { | |
e1a80002 | 649 | ether_setup(dev); |
c5441932 PS |
650 | dev->netdev_ops = &gre_tap_netdev_ops; |
651 | ip_tunnel_setup(dev, gre_tap_net_id); | |
e1a80002 HX |
652 | } |
653 | ||
c5441932 PS |
654 | static int ipgre_newlink(struct net *src_net, struct net_device *dev, |
655 | struct nlattr *tb[], struct nlattr *data[]) | |
c19e654d | 656 | { |
c5441932 | 657 | struct ip_tunnel_parm p; |
c19e654d | 658 | |
c5441932 PS |
659 | ipgre_netlink_parms(data, tb, &p); |
660 | return ip_tunnel_newlink(dev, tb, &p); | |
c19e654d HX |
661 | } |
662 | ||
663 | static int ipgre_changelink(struct net_device *dev, struct nlattr *tb[], | |
664 | struct nlattr *data[]) | |
665 | { | |
c19e654d | 666 | struct ip_tunnel_parm p; |
c19e654d | 667 | |
c5441932 PS |
668 | ipgre_netlink_parms(data, tb, &p); |
669 | return ip_tunnel_changelink(dev, tb, &p); | |
c19e654d HX |
670 | } |
671 | ||
672 | static size_t ipgre_get_size(const struct net_device *dev) | |
673 | { | |
674 | return | |
675 | /* IFLA_GRE_LINK */ | |
676 | nla_total_size(4) + | |
677 | /* IFLA_GRE_IFLAGS */ | |
678 | nla_total_size(2) + | |
679 | /* IFLA_GRE_OFLAGS */ | |
680 | nla_total_size(2) + | |
681 | /* IFLA_GRE_IKEY */ | |
682 | nla_total_size(4) + | |
683 | /* IFLA_GRE_OKEY */ | |
684 | nla_total_size(4) + | |
685 | /* IFLA_GRE_LOCAL */ | |
686 | nla_total_size(4) + | |
687 | /* IFLA_GRE_REMOTE */ | |
688 | nla_total_size(4) + | |
689 | /* IFLA_GRE_TTL */ | |
690 | nla_total_size(1) + | |
691 | /* IFLA_GRE_TOS */ | |
692 | nla_total_size(1) + | |
693 | /* IFLA_GRE_PMTUDISC */ | |
694 | nla_total_size(1) + | |
695 | 0; | |
696 | } | |
697 | ||
698 | static int ipgre_fill_info(struct sk_buff *skb, const struct net_device *dev) | |
699 | { | |
700 | struct ip_tunnel *t = netdev_priv(dev); | |
701 | struct ip_tunnel_parm *p = &t->parms; | |
702 | ||
f3756b79 | 703 | if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) || |
c5441932 PS |
704 | nla_put_be16(skb, IFLA_GRE_IFLAGS, tnl_flags_to_gre_flags(p->i_flags)) || |
705 | nla_put_be16(skb, IFLA_GRE_OFLAGS, tnl_flags_to_gre_flags(p->o_flags)) || | |
f3756b79 DM |
706 | nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) || |
707 | nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) || | |
708 | nla_put_be32(skb, IFLA_GRE_LOCAL, p->iph.saddr) || | |
709 | nla_put_be32(skb, IFLA_GRE_REMOTE, p->iph.daddr) || | |
710 | nla_put_u8(skb, IFLA_GRE_TTL, p->iph.ttl) || | |
711 | nla_put_u8(skb, IFLA_GRE_TOS, p->iph.tos) || | |
712 | nla_put_u8(skb, IFLA_GRE_PMTUDISC, | |
713 | !!(p->iph.frag_off & htons(IP_DF)))) | |
714 | goto nla_put_failure; | |
c19e654d HX |
715 | return 0; |
716 | ||
717 | nla_put_failure: | |
718 | return -EMSGSIZE; | |
719 | } | |
720 | ||
721 | static const struct nla_policy ipgre_policy[IFLA_GRE_MAX + 1] = { | |
722 | [IFLA_GRE_LINK] = { .type = NLA_U32 }, | |
723 | [IFLA_GRE_IFLAGS] = { .type = NLA_U16 }, | |
724 | [IFLA_GRE_OFLAGS] = { .type = NLA_U16 }, | |
725 | [IFLA_GRE_IKEY] = { .type = NLA_U32 }, | |
726 | [IFLA_GRE_OKEY] = { .type = NLA_U32 }, | |
4d74f8ba PM |
727 | [IFLA_GRE_LOCAL] = { .len = FIELD_SIZEOF(struct iphdr, saddr) }, |
728 | [IFLA_GRE_REMOTE] = { .len = FIELD_SIZEOF(struct iphdr, daddr) }, | |
c19e654d HX |
729 | [IFLA_GRE_TTL] = { .type = NLA_U8 }, |
730 | [IFLA_GRE_TOS] = { .type = NLA_U8 }, | |
731 | [IFLA_GRE_PMTUDISC] = { .type = NLA_U8 }, | |
732 | }; | |
733 | ||
734 | static struct rtnl_link_ops ipgre_link_ops __read_mostly = { | |
735 | .kind = "gre", | |
736 | .maxtype = IFLA_GRE_MAX, | |
737 | .policy = ipgre_policy, | |
738 | .priv_size = sizeof(struct ip_tunnel), | |
739 | .setup = ipgre_tunnel_setup, | |
740 | .validate = ipgre_tunnel_validate, | |
741 | .newlink = ipgre_newlink, | |
742 | .changelink = ipgre_changelink, | |
c5441932 | 743 | .dellink = ip_tunnel_dellink, |
c19e654d HX |
744 | .get_size = ipgre_get_size, |
745 | .fill_info = ipgre_fill_info, | |
746 | }; | |
747 | ||
e1a80002 HX |
748 | static struct rtnl_link_ops ipgre_tap_ops __read_mostly = { |
749 | .kind = "gretap", | |
750 | .maxtype = IFLA_GRE_MAX, | |
751 | .policy = ipgre_policy, | |
752 | .priv_size = sizeof(struct ip_tunnel), | |
753 | .setup = ipgre_tap_setup, | |
754 | .validate = ipgre_tap_validate, | |
755 | .newlink = ipgre_newlink, | |
756 | .changelink = ipgre_changelink, | |
c5441932 | 757 | .dellink = ip_tunnel_dellink, |
e1a80002 HX |
758 | .get_size = ipgre_get_size, |
759 | .fill_info = ipgre_fill_info, | |
760 | }; | |
761 | ||
c5441932 PS |
762 | static int __net_init ipgre_tap_init_net(struct net *net) |
763 | { | |
764 | return ip_tunnel_init_net(net, gre_tap_net_id, &ipgre_tap_ops, NULL); | |
765 | } | |
766 | ||
767 | static void __net_exit ipgre_tap_exit_net(struct net *net) | |
768 | { | |
769 | struct ip_tunnel_net *itn = net_generic(net, gre_tap_net_id); | |
6c742e71 | 770 | ip_tunnel_delete_net(itn, &ipgre_tap_ops); |
c5441932 PS |
771 | } |
772 | ||
773 | static struct pernet_operations ipgre_tap_net_ops = { | |
774 | .init = ipgre_tap_init_net, | |
775 | .exit = ipgre_tap_exit_net, | |
776 | .id = &gre_tap_net_id, | |
777 | .size = sizeof(struct ip_tunnel_net), | |
778 | }; | |
1da177e4 LT |
779 | |
780 | static int __init ipgre_init(void) | |
781 | { | |
782 | int err; | |
783 | ||
058bd4d2 | 784 | pr_info("GRE over IPv4 tunneling driver\n"); |
1da177e4 | 785 | |
cfb8fbf2 | 786 | err = register_pernet_device(&ipgre_net_ops); |
59a4c759 | 787 | if (err < 0) |
c2892f02 AD |
788 | return err; |
789 | ||
c5441932 PS |
790 | err = register_pernet_device(&ipgre_tap_net_ops); |
791 | if (err < 0) | |
792 | goto pnet_tap_faied; | |
793 | ||
bda7bb46 | 794 | err = gre_cisco_register(&ipgre_protocol); |
c2892f02 | 795 | if (err < 0) { |
058bd4d2 | 796 | pr_info("%s: can't add protocol\n", __func__); |
c2892f02 AD |
797 | goto add_proto_failed; |
798 | } | |
7daa0004 | 799 | |
c19e654d HX |
800 | err = rtnl_link_register(&ipgre_link_ops); |
801 | if (err < 0) | |
802 | goto rtnl_link_failed; | |
803 | ||
e1a80002 HX |
804 | err = rtnl_link_register(&ipgre_tap_ops); |
805 | if (err < 0) | |
806 | goto tap_ops_failed; | |
807 | ||
c5441932 | 808 | return 0; |
c19e654d | 809 | |
e1a80002 HX |
810 | tap_ops_failed: |
811 | rtnl_link_unregister(&ipgre_link_ops); | |
c19e654d | 812 | rtnl_link_failed: |
bda7bb46 | 813 | gre_cisco_unregister(&ipgre_protocol); |
c2892f02 | 814 | add_proto_failed: |
c5441932 PS |
815 | unregister_pernet_device(&ipgre_tap_net_ops); |
816 | pnet_tap_faied: | |
c2892f02 | 817 | unregister_pernet_device(&ipgre_net_ops); |
c5441932 | 818 | return err; |
1da177e4 LT |
819 | } |
820 | ||
db44575f | 821 | static void __exit ipgre_fini(void) |
1da177e4 | 822 | { |
e1a80002 | 823 | rtnl_link_unregister(&ipgre_tap_ops); |
c19e654d | 824 | rtnl_link_unregister(&ipgre_link_ops); |
bda7bb46 | 825 | gre_cisco_unregister(&ipgre_protocol); |
c5441932 | 826 | unregister_pernet_device(&ipgre_tap_net_ops); |
c2892f02 | 827 | unregister_pernet_device(&ipgre_net_ops); |
1da177e4 LT |
828 | } |
829 | ||
830 | module_init(ipgre_init); | |
831 | module_exit(ipgre_fini); | |
832 | MODULE_LICENSE("GPL"); | |
4d74f8ba PM |
833 | MODULE_ALIAS_RTNL_LINK("gre"); |
834 | MODULE_ALIAS_RTNL_LINK("gretap"); | |
8909c9ad | 835 | MODULE_ALIAS_NETDEV("gre0"); |
c5441932 | 836 | MODULE_ALIAS_NETDEV("gretap0"); |