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24#include <linux/module.h>
25#include <linux/xfrm.h>
26#include <linux/slab.h>
27#include <linux/rculist.h>
28#include <net/ip.h>
29#include <net/xfrm.h>
30#include <net/ipv6.h>
31#include <linux/ipv6.h>
32#include <linux/icmpv6.h>
33#include <linux/mutex.h>
34#include <net/netns/generic.h>
35
36#define XFRM6_TUNNEL_SPI_BYADDR_HSIZE 256
37#define XFRM6_TUNNEL_SPI_BYSPI_HSIZE 256
38
39#define XFRM6_TUNNEL_SPI_MIN 1
40#define XFRM6_TUNNEL_SPI_MAX 0xffffffff
41
42struct xfrm6_tunnel_net {
43 struct hlist_head spi_byaddr[XFRM6_TUNNEL_SPI_BYADDR_HSIZE];
44 struct hlist_head spi_byspi[XFRM6_TUNNEL_SPI_BYSPI_HSIZE];
45 u32 spi;
46};
47
48static int xfrm6_tunnel_net_id __read_mostly;
49static inline struct xfrm6_tunnel_net *xfrm6_tunnel_pernet(struct net *net)
50{
51 return net_generic(net, xfrm6_tunnel_net_id);
52}
53
54
55
56
57
58struct xfrm6_tunnel_spi {
59 struct hlist_node list_byaddr;
60 struct hlist_node list_byspi;
61 xfrm_address_t addr;
62 u32 spi;
63 atomic_t refcnt;
64 struct rcu_head rcu_head;
65};
66
67static DEFINE_SPINLOCK(xfrm6_tunnel_spi_lock);
68
69static struct kmem_cache *xfrm6_tunnel_spi_kmem __read_mostly;
70
71static inline unsigned int xfrm6_tunnel_spi_hash_byaddr(const xfrm_address_t *addr)
72{
73 unsigned int h;
74
75 h = ipv6_addr_hash((const struct in6_addr *)addr);
76 h ^= h >> 16;
77 h ^= h >> 8;
78 h &= XFRM6_TUNNEL_SPI_BYADDR_HSIZE - 1;
79
80 return h;
81}
82
83static inline unsigned int xfrm6_tunnel_spi_hash_byspi(u32 spi)
84{
85 return spi % XFRM6_TUNNEL_SPI_BYSPI_HSIZE;
86}
87
88static struct xfrm6_tunnel_spi *__xfrm6_tunnel_spi_lookup(struct net *net, const xfrm_address_t *saddr)
89{
90 struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
91 struct xfrm6_tunnel_spi *x6spi;
92
93 hlist_for_each_entry_rcu(x6spi,
94 &xfrm6_tn->spi_byaddr[xfrm6_tunnel_spi_hash_byaddr(saddr)],
95 list_byaddr) {
96 if (xfrm6_addr_equal(&x6spi->addr, saddr))
97 return x6spi;
98 }
99
100 return NULL;
101}
102
103__be32 xfrm6_tunnel_spi_lookup(struct net *net, const xfrm_address_t *saddr)
104{
105 struct xfrm6_tunnel_spi *x6spi;
106 u32 spi;
107
108 rcu_read_lock_bh();
109 x6spi = __xfrm6_tunnel_spi_lookup(net, saddr);
110 spi = x6spi ? x6spi->spi : 0;
111 rcu_read_unlock_bh();
112 return htonl(spi);
113}
114
115EXPORT_SYMBOL(xfrm6_tunnel_spi_lookup);
116
117static int __xfrm6_tunnel_spi_check(struct net *net, u32 spi)
118{
119 struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
120 struct xfrm6_tunnel_spi *x6spi;
121 int index = xfrm6_tunnel_spi_hash_byspi(spi);
122
123 hlist_for_each_entry(x6spi,
124 &xfrm6_tn->spi_byspi[index],
125 list_byspi) {
126 if (x6spi->spi == spi)
127 return -1;
128 }
129 return index;
130}
131
132static u32 __xfrm6_tunnel_alloc_spi(struct net *net, xfrm_address_t *saddr)
133{
134 struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
135 u32 spi;
136 struct xfrm6_tunnel_spi *x6spi;
137 int index;
138
139 if (xfrm6_tn->spi < XFRM6_TUNNEL_SPI_MIN ||
140 xfrm6_tn->spi >= XFRM6_TUNNEL_SPI_MAX)
141 xfrm6_tn->spi = XFRM6_TUNNEL_SPI_MIN;
142 else
143 xfrm6_tn->spi++;
144
145 for (spi = xfrm6_tn->spi; spi <= XFRM6_TUNNEL_SPI_MAX; spi++) {
146 index = __xfrm6_tunnel_spi_check(net, spi);
147 if (index >= 0)
148 goto alloc_spi;
149 }
150 for (spi = XFRM6_TUNNEL_SPI_MIN; spi < xfrm6_tn->spi; spi++) {
151 index = __xfrm6_tunnel_spi_check(net, spi);
152 if (index >= 0)
153 goto alloc_spi;
154 }
155 spi = 0;
156 goto out;
157alloc_spi:
158 xfrm6_tn->spi = spi;
159 x6spi = kmem_cache_alloc(xfrm6_tunnel_spi_kmem, GFP_ATOMIC);
160 if (!x6spi)
161 goto out;
162
163 memcpy(&x6spi->addr, saddr, sizeof(x6spi->addr));
164 x6spi->spi = spi;
165 atomic_set(&x6spi->refcnt, 1);
166
167 hlist_add_head_rcu(&x6spi->list_byspi, &xfrm6_tn->spi_byspi[index]);
168
169 index = xfrm6_tunnel_spi_hash_byaddr(saddr);
170 hlist_add_head_rcu(&x6spi->list_byaddr, &xfrm6_tn->spi_byaddr[index]);
171out:
172 return spi;
173}
174
175__be32 xfrm6_tunnel_alloc_spi(struct net *net, xfrm_address_t *saddr)
176{
177 struct xfrm6_tunnel_spi *x6spi;
178 u32 spi;
179
180 spin_lock_bh(&xfrm6_tunnel_spi_lock);
181 x6spi = __xfrm6_tunnel_spi_lookup(net, saddr);
182 if (x6spi) {
183 atomic_inc(&x6spi->refcnt);
184 spi = x6spi->spi;
185 } else
186 spi = __xfrm6_tunnel_alloc_spi(net, saddr);
187 spin_unlock_bh(&xfrm6_tunnel_spi_lock);
188
189 return htonl(spi);
190}
191
192EXPORT_SYMBOL(xfrm6_tunnel_alloc_spi);
193
194static void x6spi_destroy_rcu(struct rcu_head *head)
195{
196 kmem_cache_free(xfrm6_tunnel_spi_kmem,
197 container_of(head, struct xfrm6_tunnel_spi, rcu_head));
198}
199
200static void xfrm6_tunnel_free_spi(struct net *net, xfrm_address_t *saddr)
201{
202 struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
203 struct xfrm6_tunnel_spi *x6spi;
204 struct hlist_node *n;
205
206 spin_lock_bh(&xfrm6_tunnel_spi_lock);
207
208 hlist_for_each_entry_safe(x6spi, n,
209 &xfrm6_tn->spi_byaddr[xfrm6_tunnel_spi_hash_byaddr(saddr)],
210 list_byaddr)
211 {
212 if (xfrm6_addr_equal(&x6spi->addr, saddr)) {
213 if (atomic_dec_and_test(&x6spi->refcnt)) {
214 hlist_del_rcu(&x6spi->list_byaddr);
215 hlist_del_rcu(&x6spi->list_byspi);
216 call_rcu(&x6spi->rcu_head, x6spi_destroy_rcu);
217 break;
218 }
219 }
220 }
221 spin_unlock_bh(&xfrm6_tunnel_spi_lock);
222}
223
224static int xfrm6_tunnel_output(struct xfrm_state *x, struct sk_buff *skb)
225{
226 skb_push(skb, -skb_network_offset(skb));
227 return 0;
228}
229
230static int xfrm6_tunnel_input(struct xfrm_state *x, struct sk_buff *skb)
231{
232 return skb_network_header(skb)[IP6CB(skb)->nhoff];
233}
234
235static int xfrm6_tunnel_rcv(struct sk_buff *skb)
236{
237 struct net *net = dev_net(skb->dev);
238 const struct ipv6hdr *iph = ipv6_hdr(skb);
239 __be32 spi;
240
241 spi = xfrm6_tunnel_spi_lookup(net, (const xfrm_address_t *)&iph->saddr);
242 return xfrm6_rcv_spi(skb, IPPROTO_IPV6, spi);
243}
244
245static int xfrm6_tunnel_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
246 u8 type, u8 code, int offset, __be32 info)
247{
248
249 switch (type) {
250 case ICMPV6_DEST_UNREACH:
251 switch (code) {
252 case ICMPV6_NOROUTE:
253 case ICMPV6_ADM_PROHIBITED:
254 case ICMPV6_NOT_NEIGHBOUR:
255 case ICMPV6_ADDR_UNREACH:
256 case ICMPV6_PORT_UNREACH:
257 default:
258 break;
259 }
260 break;
261 case ICMPV6_PKT_TOOBIG:
262 break;
263 case ICMPV6_TIME_EXCEED:
264 switch (code) {
265 case ICMPV6_EXC_HOPLIMIT:
266 break;
267 case ICMPV6_EXC_FRAGTIME:
268 default:
269 break;
270 }
271 break;
272 case ICMPV6_PARAMPROB:
273 switch (code) {
274 case ICMPV6_HDR_FIELD: break;
275 case ICMPV6_UNK_NEXTHDR: break;
276 case ICMPV6_UNK_OPTION: break;
277 }
278 break;
279 default:
280 break;
281 }
282
283 return 0;
284}
285
286static int xfrm6_tunnel_init_state(struct xfrm_state *x)
287{
288 if (x->props.mode != XFRM_MODE_TUNNEL)
289 return -EINVAL;
290
291 if (x->encap)
292 return -EINVAL;
293
294 x->props.header_len = sizeof(struct ipv6hdr);
295
296 return 0;
297}
298
299static void xfrm6_tunnel_destroy(struct xfrm_state *x)
300{
301 struct net *net = xs_net(x);
302
303 xfrm6_tunnel_free_spi(net, (xfrm_address_t *)&x->props.saddr);
304}
305
306static const struct xfrm_type xfrm6_tunnel_type = {
307 .description = "IP6IP6",
308 .owner = THIS_MODULE,
309 .proto = IPPROTO_IPV6,
310 .init_state = xfrm6_tunnel_init_state,
311 .destructor = xfrm6_tunnel_destroy,
312 .input = xfrm6_tunnel_input,
313 .output = xfrm6_tunnel_output,
314};
315
316static struct xfrm6_tunnel xfrm6_tunnel_handler __read_mostly = {
317 .handler = xfrm6_tunnel_rcv,
318 .err_handler = xfrm6_tunnel_err,
319 .priority = 2,
320};
321
322static struct xfrm6_tunnel xfrm46_tunnel_handler __read_mostly = {
323 .handler = xfrm6_tunnel_rcv,
324 .err_handler = xfrm6_tunnel_err,
325 .priority = 2,
326};
327
328static int __net_init xfrm6_tunnel_net_init(struct net *net)
329{
330 struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
331 unsigned int i;
332
333 for (i = 0; i < XFRM6_TUNNEL_SPI_BYADDR_HSIZE; i++)
334 INIT_HLIST_HEAD(&xfrm6_tn->spi_byaddr[i]);
335 for (i = 0; i < XFRM6_TUNNEL_SPI_BYSPI_HSIZE; i++)
336 INIT_HLIST_HEAD(&xfrm6_tn->spi_byspi[i]);
337 xfrm6_tn->spi = 0;
338
339 return 0;
340}
341
342static void __net_exit xfrm6_tunnel_net_exit(struct net *net)
343{
344}
345
346static struct pernet_operations xfrm6_tunnel_net_ops = {
347 .init = xfrm6_tunnel_net_init,
348 .exit = xfrm6_tunnel_net_exit,
349 .id = &xfrm6_tunnel_net_id,
350 .size = sizeof(struct xfrm6_tunnel_net),
351};
352
353static int __init xfrm6_tunnel_init(void)
354{
355 int rv;
356
357 xfrm6_tunnel_spi_kmem = kmem_cache_create("xfrm6_tunnel_spi",
358 sizeof(struct xfrm6_tunnel_spi),
359 0, SLAB_HWCACHE_ALIGN,
360 NULL);
361 if (!xfrm6_tunnel_spi_kmem)
362 return -ENOMEM;
363 rv = register_pernet_subsys(&xfrm6_tunnel_net_ops);
364 if (rv < 0)
365 goto out_pernet;
366 rv = xfrm_register_type(&xfrm6_tunnel_type, AF_INET6);
367 if (rv < 0)
368 goto out_type;
369 rv = xfrm6_tunnel_register(&xfrm6_tunnel_handler, AF_INET6);
370 if (rv < 0)
371 goto out_xfrm6;
372 rv = xfrm6_tunnel_register(&xfrm46_tunnel_handler, AF_INET);
373 if (rv < 0)
374 goto out_xfrm46;
375 return 0;
376
377out_xfrm46:
378 xfrm6_tunnel_deregister(&xfrm6_tunnel_handler, AF_INET6);
379out_xfrm6:
380 xfrm_unregister_type(&xfrm6_tunnel_type, AF_INET6);
381out_type:
382 unregister_pernet_subsys(&xfrm6_tunnel_net_ops);
383out_pernet:
384 kmem_cache_destroy(xfrm6_tunnel_spi_kmem);
385 return rv;
386}
387
388static void __exit xfrm6_tunnel_fini(void)
389{
390 xfrm6_tunnel_deregister(&xfrm46_tunnel_handler, AF_INET);
391 xfrm6_tunnel_deregister(&xfrm6_tunnel_handler, AF_INET6);
392 xfrm_unregister_type(&xfrm6_tunnel_type, AF_INET6);
393 unregister_pernet_subsys(&xfrm6_tunnel_net_ops);
394 kmem_cache_destroy(xfrm6_tunnel_spi_kmem);
395}
396
397module_init(xfrm6_tunnel_init);
398module_exit(xfrm6_tunnel_fini);
399MODULE_LICENSE("GPL");
400MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_IPV6);
401
