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10#include <linux/module.h>
11#include <linux/xfrm.h>
12#include <linux/slab.h>
13#include <linux/rculist.h>
14#include <net/ip.h>
15#include <net/xfrm.h>
16#include <net/ipv6.h>
17#include <linux/ipv6.h>
18#include <linux/icmpv6.h>
19#include <linux/mutex.h>
20#include <net/netns/generic.h>
21
22#define XFRM6_TUNNEL_SPI_BYADDR_HSIZE 256
23#define XFRM6_TUNNEL_SPI_BYSPI_HSIZE 256
24
25#define XFRM6_TUNNEL_SPI_MIN 1
26#define XFRM6_TUNNEL_SPI_MAX 0xffffffff
27
28struct xfrm6_tunnel_net {
29 struct hlist_head spi_byaddr[XFRM6_TUNNEL_SPI_BYADDR_HSIZE];
30 struct hlist_head spi_byspi[XFRM6_TUNNEL_SPI_BYSPI_HSIZE];
31 u32 spi;
32};
33
34static unsigned int xfrm6_tunnel_net_id __read_mostly;
35static inline struct xfrm6_tunnel_net *xfrm6_tunnel_pernet(struct net *net)
36{
37 return net_generic(net, xfrm6_tunnel_net_id);
38}
39
40
41
42
43
44struct xfrm6_tunnel_spi {
45 struct hlist_node list_byaddr;
46 struct hlist_node list_byspi;
47 xfrm_address_t addr;
48 u32 spi;
49 refcount_t refcnt;
50 struct rcu_head rcu_head;
51};
52
53static DEFINE_SPINLOCK(xfrm6_tunnel_spi_lock);
54
55static struct kmem_cache *xfrm6_tunnel_spi_kmem __read_mostly;
56
57static inline unsigned int xfrm6_tunnel_spi_hash_byaddr(const xfrm_address_t *addr)
58{
59 unsigned int h;
60
61 h = ipv6_addr_hash((const struct in6_addr *)addr);
62 h ^= h >> 16;
63 h ^= h >> 8;
64 h &= XFRM6_TUNNEL_SPI_BYADDR_HSIZE - 1;
65
66 return h;
67}
68
69static inline unsigned int xfrm6_tunnel_spi_hash_byspi(u32 spi)
70{
71 return spi % XFRM6_TUNNEL_SPI_BYSPI_HSIZE;
72}
73
74static struct xfrm6_tunnel_spi *__xfrm6_tunnel_spi_lookup(struct net *net, const xfrm_address_t *saddr)
75{
76 struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
77 struct xfrm6_tunnel_spi *x6spi;
78
79 hlist_for_each_entry_rcu(x6spi,
80 &xfrm6_tn->spi_byaddr[xfrm6_tunnel_spi_hash_byaddr(saddr)],
81 list_byaddr) {
82 if (xfrm6_addr_equal(&x6spi->addr, saddr))
83 return x6spi;
84 }
85
86 return NULL;
87}
88
89__be32 xfrm6_tunnel_spi_lookup(struct net *net, const xfrm_address_t *saddr)
90{
91 struct xfrm6_tunnel_spi *x6spi;
92 u32 spi;
93
94 rcu_read_lock_bh();
95 x6spi = __xfrm6_tunnel_spi_lookup(net, saddr);
96 spi = x6spi ? x6spi->spi : 0;
97 rcu_read_unlock_bh();
98 return htonl(spi);
99}
100EXPORT_SYMBOL(xfrm6_tunnel_spi_lookup);
101
102static int __xfrm6_tunnel_spi_check(struct net *net, u32 spi)
103{
104 struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
105 struct xfrm6_tunnel_spi *x6spi;
106 int index = xfrm6_tunnel_spi_hash_byspi(spi);
107
108 hlist_for_each_entry(x6spi,
109 &xfrm6_tn->spi_byspi[index],
110 list_byspi) {
111 if (x6spi->spi == spi)
112 return -1;
113 }
114 return index;
115}
116
117static u32 __xfrm6_tunnel_alloc_spi(struct net *net, xfrm_address_t *saddr)
118{
119 struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
120 u32 spi;
121 struct xfrm6_tunnel_spi *x6spi;
122 int index;
123
124 if (xfrm6_tn->spi < XFRM6_TUNNEL_SPI_MIN ||
125 xfrm6_tn->spi >= XFRM6_TUNNEL_SPI_MAX)
126 xfrm6_tn->spi = XFRM6_TUNNEL_SPI_MIN;
127 else
128 xfrm6_tn->spi++;
129
130 for (spi = xfrm6_tn->spi; spi <= XFRM6_TUNNEL_SPI_MAX; spi++) {
131 index = __xfrm6_tunnel_spi_check(net, spi);
132 if (index >= 0)
133 goto alloc_spi;
134
135 if (spi == XFRM6_TUNNEL_SPI_MAX)
136 break;
137 }
138 for (spi = XFRM6_TUNNEL_SPI_MIN; spi < xfrm6_tn->spi; spi++) {
139 index = __xfrm6_tunnel_spi_check(net, spi);
140 if (index >= 0)
141 goto alloc_spi;
142 }
143 spi = 0;
144 goto out;
145alloc_spi:
146 xfrm6_tn->spi = spi;
147 x6spi = kmem_cache_alloc(xfrm6_tunnel_spi_kmem, GFP_ATOMIC);
148 if (!x6spi)
149 goto out;
150
151 memcpy(&x6spi->addr, saddr, sizeof(x6spi->addr));
152 x6spi->spi = spi;
153 refcount_set(&x6spi->refcnt, 1);
154
155 hlist_add_head_rcu(&x6spi->list_byspi, &xfrm6_tn->spi_byspi[index]);
156
157 index = xfrm6_tunnel_spi_hash_byaddr(saddr);
158 hlist_add_head_rcu(&x6spi->list_byaddr, &xfrm6_tn->spi_byaddr[index]);
159out:
160 return spi;
161}
162
163__be32 xfrm6_tunnel_alloc_spi(struct net *net, xfrm_address_t *saddr)
164{
165 struct xfrm6_tunnel_spi *x6spi;
166 u32 spi;
167
168 spin_lock_bh(&xfrm6_tunnel_spi_lock);
169 x6spi = __xfrm6_tunnel_spi_lookup(net, saddr);
170 if (x6spi) {
171 refcount_inc(&x6spi->refcnt);
172 spi = x6spi->spi;
173 } else
174 spi = __xfrm6_tunnel_alloc_spi(net, saddr);
175 spin_unlock_bh(&xfrm6_tunnel_spi_lock);
176
177 return htonl(spi);
178}
179EXPORT_SYMBOL(xfrm6_tunnel_alloc_spi);
180
181static void x6spi_destroy_rcu(struct rcu_head *head)
182{
183 kmem_cache_free(xfrm6_tunnel_spi_kmem,
184 container_of(head, struct xfrm6_tunnel_spi, rcu_head));
185}
186
187static void xfrm6_tunnel_free_spi(struct net *net, xfrm_address_t *saddr)
188{
189 struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
190 struct xfrm6_tunnel_spi *x6spi;
191 struct hlist_node *n;
192
193 spin_lock_bh(&xfrm6_tunnel_spi_lock);
194
195 hlist_for_each_entry_safe(x6spi, n,
196 &xfrm6_tn->spi_byaddr[xfrm6_tunnel_spi_hash_byaddr(saddr)],
197 list_byaddr)
198 {
199 if (xfrm6_addr_equal(&x6spi->addr, saddr)) {
200 if (refcount_dec_and_test(&x6spi->refcnt)) {
201 hlist_del_rcu(&x6spi->list_byaddr);
202 hlist_del_rcu(&x6spi->list_byspi);
203 call_rcu(&x6spi->rcu_head, x6spi_destroy_rcu);
204 break;
205 }
206 }
207 }
208 spin_unlock_bh(&xfrm6_tunnel_spi_lock);
209}
210
211static int xfrm6_tunnel_output(struct xfrm_state *x, struct sk_buff *skb)
212{
213 skb_push(skb, -skb_network_offset(skb));
214 return 0;
215}
216
217static int xfrm6_tunnel_input(struct xfrm_state *x, struct sk_buff *skb)
218{
219 return skb_network_header(skb)[IP6CB(skb)->nhoff];
220}
221
222static int xfrm6_tunnel_rcv(struct sk_buff *skb)
223{
224 struct net *net = dev_net(skb->dev);
225 const struct ipv6hdr *iph = ipv6_hdr(skb);
226 __be32 spi;
227
228 spi = xfrm6_tunnel_spi_lookup(net, (const xfrm_address_t *)&iph->saddr);
229 return xfrm6_rcv_spi(skb, IPPROTO_IPV6, spi, NULL);
230}
231
232static int xfrm6_tunnel_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
233 u8 type, u8 code, int offset, __be32 info)
234{
235
236 switch (type) {
237 case ICMPV6_DEST_UNREACH:
238 switch (code) {
239 case ICMPV6_NOROUTE:
240 case ICMPV6_ADM_PROHIBITED:
241 case ICMPV6_NOT_NEIGHBOUR:
242 case ICMPV6_ADDR_UNREACH:
243 case ICMPV6_PORT_UNREACH:
244 default:
245 break;
246 }
247 break;
248 case ICMPV6_PKT_TOOBIG:
249 break;
250 case ICMPV6_TIME_EXCEED:
251 switch (code) {
252 case ICMPV6_EXC_HOPLIMIT:
253 break;
254 case ICMPV6_EXC_FRAGTIME:
255 default:
256 break;
257 }
258 break;
259 case ICMPV6_PARAMPROB:
260 switch (code) {
261 case ICMPV6_HDR_FIELD: break;
262 case ICMPV6_UNK_NEXTHDR: break;
263 case ICMPV6_UNK_OPTION: break;
264 }
265 break;
266 default:
267 break;
268 }
269
270 return 0;
271}
272
273static int xfrm6_tunnel_init_state(struct xfrm_state *x)
274{
275 if (x->props.mode != XFRM_MODE_TUNNEL)
276 return -EINVAL;
277
278 if (x->encap)
279 return -EINVAL;
280
281 x->props.header_len = sizeof(struct ipv6hdr);
282
283 return 0;
284}
285
286static void xfrm6_tunnel_destroy(struct xfrm_state *x)
287{
288 struct net *net = xs_net(x);
289
290 xfrm6_tunnel_free_spi(net, (xfrm_address_t *)&x->props.saddr);
291}
292
293static const struct xfrm_type xfrm6_tunnel_type = {
294 .description = "IP6IP6",
295 .owner = THIS_MODULE,
296 .proto = IPPROTO_IPV6,
297 .init_state = xfrm6_tunnel_init_state,
298 .destructor = xfrm6_tunnel_destroy,
299 .input = xfrm6_tunnel_input,
300 .output = xfrm6_tunnel_output,
301};
302
303static struct xfrm6_tunnel xfrm6_tunnel_handler __read_mostly = {
304 .handler = xfrm6_tunnel_rcv,
305 .err_handler = xfrm6_tunnel_err,
306 .priority = 2,
307};
308
309static struct xfrm6_tunnel xfrm46_tunnel_handler __read_mostly = {
310 .handler = xfrm6_tunnel_rcv,
311 .err_handler = xfrm6_tunnel_err,
312 .priority = 2,
313};
314
315static int __net_init xfrm6_tunnel_net_init(struct net *net)
316{
317 struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
318 unsigned int i;
319
320 for (i = 0; i < XFRM6_TUNNEL_SPI_BYADDR_HSIZE; i++)
321 INIT_HLIST_HEAD(&xfrm6_tn->spi_byaddr[i]);
322 for (i = 0; i < XFRM6_TUNNEL_SPI_BYSPI_HSIZE; i++)
323 INIT_HLIST_HEAD(&xfrm6_tn->spi_byspi[i]);
324 xfrm6_tn->spi = 0;
325
326 return 0;
327}
328
329static void __net_exit xfrm6_tunnel_net_exit(struct net *net)
330{
331 struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
332 unsigned int i;
333
334 xfrm_flush_gc();
335 xfrm_state_flush(net, 0, false, true);
336
337 for (i = 0; i < XFRM6_TUNNEL_SPI_BYADDR_HSIZE; i++)
338 WARN_ON_ONCE(!hlist_empty(&xfrm6_tn->spi_byaddr[i]));
339
340 for (i = 0; i < XFRM6_TUNNEL_SPI_BYSPI_HSIZE; i++)
341 WARN_ON_ONCE(!hlist_empty(&xfrm6_tn->spi_byspi[i]));
342}
343
344static struct pernet_operations xfrm6_tunnel_net_ops = {
345 .init = xfrm6_tunnel_net_init,
346 .exit = xfrm6_tunnel_net_exit,
347 .id = &xfrm6_tunnel_net_id,
348 .size = sizeof(struct xfrm6_tunnel_net),
349};
350
351static int __init xfrm6_tunnel_init(void)
352{
353 int rv;
354
355 xfrm6_tunnel_spi_kmem = kmem_cache_create("xfrm6_tunnel_spi",
356 sizeof(struct xfrm6_tunnel_spi),
357 0, SLAB_HWCACHE_ALIGN,
358 NULL);
359 if (!xfrm6_tunnel_spi_kmem)
360 return -ENOMEM;
361 rv = register_pernet_subsys(&xfrm6_tunnel_net_ops);
362 if (rv < 0)
363 goto out_pernet;
364 rv = xfrm_register_type(&xfrm6_tunnel_type, AF_INET6);
365 if (rv < 0)
366 goto out_type;
367 rv = xfrm6_tunnel_register(&xfrm6_tunnel_handler, AF_INET6);
368 if (rv < 0)
369 goto out_xfrm6;
370 rv = xfrm6_tunnel_register(&xfrm46_tunnel_handler, AF_INET);
371 if (rv < 0)
372 goto out_xfrm46;
373 return 0;
374
375out_xfrm46:
376 xfrm6_tunnel_deregister(&xfrm6_tunnel_handler, AF_INET6);
377out_xfrm6:
378 xfrm_unregister_type(&xfrm6_tunnel_type, AF_INET6);
379out_type:
380 unregister_pernet_subsys(&xfrm6_tunnel_net_ops);
381out_pernet:
382 kmem_cache_destroy(xfrm6_tunnel_spi_kmem);
383 return rv;
384}
385
386static void __exit xfrm6_tunnel_fini(void)
387{
388 xfrm6_tunnel_deregister(&xfrm46_tunnel_handler, AF_INET);
389 xfrm6_tunnel_deregister(&xfrm6_tunnel_handler, AF_INET6);
390 xfrm_unregister_type(&xfrm6_tunnel_type, AF_INET6);
391 unregister_pernet_subsys(&xfrm6_tunnel_net_ops);
392
393
394
395 rcu_barrier();
396 kmem_cache_destroy(xfrm6_tunnel_spi_kmem);
397}
398
399module_init(xfrm6_tunnel_init);
400module_exit(xfrm6_tunnel_fini);
401MODULE_LICENSE("GPL");
402MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_IPV6);
403
