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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 xfrm6_tunnel_spi_hash_byaddr(xfrm_address_t *addr)
72{
73 unsigned h;
74
75 h = (__force u32)(addr->a6[0] ^ addr->a6[1] ^ addr->a6[2] ^ addr->a6[3]);
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 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, xfrm_address_t *saddr)
89{
90 struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
91 struct xfrm6_tunnel_spi *x6spi;
92 struct hlist_node *pos;
93
94 hlist_for_each_entry_rcu(x6spi, pos,
95 &xfrm6_tn->spi_byaddr[xfrm6_tunnel_spi_hash_byaddr(saddr)],
96 list_byaddr) {
97 if (memcmp(&x6spi->addr, saddr, sizeof(x6spi->addr)) == 0)
98 return x6spi;
99 }
100
101 return NULL;
102}
103
104__be32 xfrm6_tunnel_spi_lookup(struct net *net, xfrm_address_t *saddr)
105{
106 struct xfrm6_tunnel_spi *x6spi;
107 u32 spi;
108
109 rcu_read_lock_bh();
110 x6spi = __xfrm6_tunnel_spi_lookup(net, saddr);
111 spi = x6spi ? x6spi->spi : 0;
112 rcu_read_unlock_bh();
113 return htonl(spi);
114}
115
116EXPORT_SYMBOL(xfrm6_tunnel_spi_lookup);
117
118static int __xfrm6_tunnel_spi_check(struct net *net, u32 spi)
119{
120 struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
121 struct xfrm6_tunnel_spi *x6spi;
122 int index = xfrm6_tunnel_spi_hash_byspi(spi);
123 struct hlist_node *pos;
124
125 hlist_for_each_entry(x6spi, pos,
126 &xfrm6_tn->spi_byspi[index],
127 list_byspi) {
128 if (x6spi->spi == spi)
129 return -1;
130 }
131 return index;
132}
133
134static u32 __xfrm6_tunnel_alloc_spi(struct net *net, xfrm_address_t *saddr)
135{
136 struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
137 u32 spi;
138 struct xfrm6_tunnel_spi *x6spi;
139 int index;
140
141 if (xfrm6_tn->spi < XFRM6_TUNNEL_SPI_MIN ||
142 xfrm6_tn->spi >= XFRM6_TUNNEL_SPI_MAX)
143 xfrm6_tn->spi = XFRM6_TUNNEL_SPI_MIN;
144 else
145 xfrm6_tn->spi++;
146
147 for (spi = xfrm6_tn->spi; spi <= XFRM6_TUNNEL_SPI_MAX; spi++) {
148 index = __xfrm6_tunnel_spi_check(net, spi);
149 if (index >= 0)
150 goto alloc_spi;
151 }
152 for (spi = XFRM6_TUNNEL_SPI_MIN; spi < xfrm6_tn->spi; spi++) {
153 index = __xfrm6_tunnel_spi_check(net, spi);
154 if (index >= 0)
155 goto alloc_spi;
156 }
157 spi = 0;
158 goto out;
159alloc_spi:
160 xfrm6_tn->spi = spi;
161 x6spi = kmem_cache_alloc(xfrm6_tunnel_spi_kmem, GFP_ATOMIC);
162 if (!x6spi)
163 goto out;
164
165 memcpy(&x6spi->addr, saddr, sizeof(x6spi->addr));
166 x6spi->spi = spi;
167 atomic_set(&x6spi->refcnt, 1);
168
169 hlist_add_head_rcu(&x6spi->list_byspi, &xfrm6_tn->spi_byspi[index]);
170
171 index = xfrm6_tunnel_spi_hash_byaddr(saddr);
172 hlist_add_head_rcu(&x6spi->list_byaddr, &xfrm6_tn->spi_byaddr[index]);
173out:
174 return spi;
175}
176
177__be32 xfrm6_tunnel_alloc_spi(struct net *net, xfrm_address_t *saddr)
178{
179 struct xfrm6_tunnel_spi *x6spi;
180 u32 spi;
181
182 spin_lock_bh(&xfrm6_tunnel_spi_lock);
183 x6spi = __xfrm6_tunnel_spi_lookup(net, saddr);
184 if (x6spi) {
185 atomic_inc(&x6spi->refcnt);
186 spi = x6spi->spi;
187 } else
188 spi = __xfrm6_tunnel_alloc_spi(net, saddr);
189 spin_unlock_bh(&xfrm6_tunnel_spi_lock);
190
191 return htonl(spi);
192}
193
194EXPORT_SYMBOL(xfrm6_tunnel_alloc_spi);
195
196static void x6spi_destroy_rcu(struct rcu_head *head)
197{
198 kmem_cache_free(xfrm6_tunnel_spi_kmem,
199 container_of(head, struct xfrm6_tunnel_spi, rcu_head));
200}
201
202void xfrm6_tunnel_free_spi(struct net *net, xfrm_address_t *saddr)
203{
204 struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
205 struct xfrm6_tunnel_spi *x6spi;
206 struct hlist_node *pos, *n;
207
208 spin_lock_bh(&xfrm6_tunnel_spi_lock);
209
210 hlist_for_each_entry_safe(x6spi, pos, n,
211 &xfrm6_tn->spi_byaddr[xfrm6_tunnel_spi_hash_byaddr(saddr)],
212 list_byaddr)
213 {
214 if (memcmp(&x6spi->addr, saddr, sizeof(x6spi->addr)) == 0) {
215 if (atomic_dec_and_test(&x6spi->refcnt)) {
216 hlist_del_rcu(&x6spi->list_byaddr);
217 hlist_del_rcu(&x6spi->list_byspi);
218 call_rcu(&x6spi->rcu_head, x6spi_destroy_rcu);
219 break;
220 }
221 }
222 }
223 spin_unlock_bh(&xfrm6_tunnel_spi_lock);
224}
225
226EXPORT_SYMBOL(xfrm6_tunnel_free_spi);
227
228static int xfrm6_tunnel_output(struct xfrm_state *x, struct sk_buff *skb)
229{
230 skb_push(skb, -skb_network_offset(skb));
231 return 0;
232}
233
234static int xfrm6_tunnel_input(struct xfrm_state *x, struct sk_buff *skb)
235{
236 return skb_network_header(skb)[IP6CB(skb)->nhoff];
237}
238
239static int xfrm6_tunnel_rcv(struct sk_buff *skb)
240{
241 struct net *net = dev_net(skb->dev);
242 struct ipv6hdr *iph = ipv6_hdr(skb);
243 __be32 spi;
244
245 spi = xfrm6_tunnel_spi_lookup(net, (xfrm_address_t *)&iph->saddr);
246 return xfrm6_rcv_spi(skb, IPPROTO_IPV6, spi) > 0 ? : 0;
247}
248
249static int xfrm6_tunnel_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
250 u8 type, u8 code, int offset, __be32 info)
251{
252
253 switch (type) {
254 case ICMPV6_DEST_UNREACH:
255 switch (code) {
256 case ICMPV6_NOROUTE:
257 case ICMPV6_ADM_PROHIBITED:
258 case ICMPV6_NOT_NEIGHBOUR:
259 case ICMPV6_ADDR_UNREACH:
260 case ICMPV6_PORT_UNREACH:
261 default:
262 break;
263 }
264 break;
265 case ICMPV6_PKT_TOOBIG:
266 break;
267 case ICMPV6_TIME_EXCEED:
268 switch (code) {
269 case ICMPV6_EXC_HOPLIMIT:
270 break;
271 case ICMPV6_EXC_FRAGTIME:
272 default:
273 break;
274 }
275 break;
276 case ICMPV6_PARAMPROB:
277 switch (code) {
278 case ICMPV6_HDR_FIELD: break;
279 case ICMPV6_UNK_NEXTHDR: break;
280 case ICMPV6_UNK_OPTION: break;
281 }
282 break;
283 default:
284 break;
285 }
286
287 return 0;
288}
289
290static int xfrm6_tunnel_init_state(struct xfrm_state *x)
291{
292 if (x->props.mode != XFRM_MODE_TUNNEL)
293 return -EINVAL;
294
295 if (x->encap)
296 return -EINVAL;
297
298 x->props.header_len = sizeof(struct ipv6hdr);
299
300 return 0;
301}
302
303static void xfrm6_tunnel_destroy(struct xfrm_state *x)
304{
305 struct net *net = xs_net(x);
306
307 xfrm6_tunnel_free_spi(net, (xfrm_address_t *)&x->props.saddr);
308}
309
310static const struct xfrm_type xfrm6_tunnel_type = {
311 .description = "IP6IP6",
312 .owner = THIS_MODULE,
313 .proto = IPPROTO_IPV6,
314 .init_state = xfrm6_tunnel_init_state,
315 .destructor = xfrm6_tunnel_destroy,
316 .input = xfrm6_tunnel_input,
317 .output = xfrm6_tunnel_output,
318};
319
320static struct xfrm6_tunnel xfrm6_tunnel_handler = {
321 .handler = xfrm6_tunnel_rcv,
322 .err_handler = xfrm6_tunnel_err,
323 .priority = 2,
324};
325
326static struct xfrm6_tunnel xfrm46_tunnel_handler = {
327 .handler = xfrm6_tunnel_rcv,
328 .err_handler = xfrm6_tunnel_err,
329 .priority = 2,
330};
331
332static int __net_init xfrm6_tunnel_net_init(struct net *net)
333{
334 struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
335 unsigned int i;
336
337 for (i = 0; i < XFRM6_TUNNEL_SPI_BYADDR_HSIZE; i++)
338 INIT_HLIST_HEAD(&xfrm6_tn->spi_byaddr[i]);
339 for (i = 0; i < XFRM6_TUNNEL_SPI_BYSPI_HSIZE; i++)
340 INIT_HLIST_HEAD(&xfrm6_tn->spi_byspi[i]);
341 xfrm6_tn->spi = 0;
342
343 return 0;
344}
345
346static void __net_exit xfrm6_tunnel_net_exit(struct net *net)
347{
348}
349
350static struct pernet_operations xfrm6_tunnel_net_ops = {
351 .init = xfrm6_tunnel_net_init,
352 .exit = xfrm6_tunnel_net_exit,
353 .id = &xfrm6_tunnel_net_id,
354 .size = sizeof(struct xfrm6_tunnel_net),
355};
356
357static int __init xfrm6_tunnel_init(void)
358{
359 int rv;
360
361 xfrm6_tunnel_spi_kmem = kmem_cache_create("xfrm6_tunnel_spi",
362 sizeof(struct xfrm6_tunnel_spi),
363 0, SLAB_HWCACHE_ALIGN,
364 NULL);
365 if (!xfrm6_tunnel_spi_kmem)
366 return -ENOMEM;
367 rv = register_pernet_subsys(&xfrm6_tunnel_net_ops);
368 if (rv < 0)
369 goto out_pernet;
370 rv = xfrm_register_type(&xfrm6_tunnel_type, AF_INET6);
371 if (rv < 0)
372 goto out_type;
373 rv = xfrm6_tunnel_register(&xfrm6_tunnel_handler, AF_INET6);
374 if (rv < 0)
375 goto out_xfrm6;
376 rv = xfrm6_tunnel_register(&xfrm46_tunnel_handler, AF_INET);
377 if (rv < 0)
378 goto out_xfrm46;
379 return 0;
380
381out_xfrm46:
382 xfrm6_tunnel_deregister(&xfrm6_tunnel_handler, AF_INET6);
383out_xfrm6:
384 xfrm_unregister_type(&xfrm6_tunnel_type, AF_INET6);
385out_type:
386 unregister_pernet_subsys(&xfrm6_tunnel_net_ops);
387out_pernet:
388 kmem_cache_destroy(xfrm6_tunnel_spi_kmem);
389 return rv;
390}
391
392static void __exit xfrm6_tunnel_fini(void)
393{
394 xfrm6_tunnel_deregister(&xfrm46_tunnel_handler, AF_INET);
395 xfrm6_tunnel_deregister(&xfrm6_tunnel_handler, AF_INET6);
396 xfrm_unregister_type(&xfrm6_tunnel_type, AF_INET6);
397 unregister_pernet_subsys(&xfrm6_tunnel_net_ops);
398 kmem_cache_destroy(xfrm6_tunnel_spi_kmem);
399}
400
401module_init(xfrm6_tunnel_init);
402module_exit(xfrm6_tunnel_fini);
403MODULE_LICENSE("GPL");
404MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_IPV6);
405
