treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 13
[linux-2.6-block.git] / net / ipv6 / xfrm6_tunnel.c
CommitLineData
1ccea77e 1// SPDX-License-Identifier: GPL-2.0-or-later
1da177e4
LT
2/*
3 * Copyright (C)2003,2004 USAGI/WIDE Project
4 *
1da177e4 5 * Authors Mitsuru KANDA <mk@linux-ipv6.org>
67ba4152 6 * YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
1da177e4
LT
7 *
8 * Based on net/ipv4/xfrm4_tunnel.c
1da177e4 9 */
1da177e4
LT
10#include <linux/module.h>
11#include <linux/xfrm.h>
5a0e3ad6 12#include <linux/slab.h>
91cc3bb0 13#include <linux/rculist.h>
1da177e4
LT
14#include <net/ip.h>
15#include <net/xfrm.h>
16#include <net/ipv6.h>
1da177e4
LT
17#include <linux/ipv6.h>
18#include <linux/icmpv6.h>
4a3e2f71 19#include <linux/mutex.h>
a1664773
AD
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
c7d03a00 34static unsigned int xfrm6_tunnel_net_id __read_mostly;
a1664773
AD
35static inline struct xfrm6_tunnel_net *xfrm6_tunnel_pernet(struct net *net)
36{
37 return net_generic(net, xfrm6_tunnel_net_id);
38}
1da177e4 39
1da177e4 40/*
1ab1457c 41 * xfrm_tunnel_spi things are for allocating unique id ("spi")
1da177e4
LT
42 * per xfrm_address_t.
43 */
44struct xfrm6_tunnel_spi {
91cc3bb0
ED
45 struct hlist_node list_byaddr;
46 struct hlist_node list_byspi;
47 xfrm_address_t addr;
48 u32 spi;
d12f3827 49 refcount_t refcnt;
91cc3bb0 50 struct rcu_head rcu_head;
1da177e4
LT
51};
52
91cc3bb0 53static DEFINE_SPINLOCK(xfrm6_tunnel_spi_lock);
1da177e4 54
e18b890b 55static struct kmem_cache *xfrm6_tunnel_spi_kmem __read_mostly;
1da177e4 56
95c96174 57static inline unsigned int xfrm6_tunnel_spi_hash_byaddr(const xfrm_address_t *addr)
1da177e4 58{
95c96174 59 unsigned int h;
1da177e4 60
2b464f61 61 h = ipv6_addr_hash((const struct in6_addr *)addr);
1da177e4
LT
62 h ^= h >> 16;
63 h ^= h >> 8;
64 h &= XFRM6_TUNNEL_SPI_BYADDR_HSIZE - 1;
65
1da177e4
LT
66 return h;
67}
68
95c96174 69static inline unsigned int xfrm6_tunnel_spi_hash_byspi(u32 spi)
1da177e4
LT
70{
71 return spi % XFRM6_TUNNEL_SPI_BYSPI_HSIZE;
72}
73
b71d1d42 74static struct xfrm6_tunnel_spi *__xfrm6_tunnel_spi_lookup(struct net *net, const xfrm_address_t *saddr)
1da177e4 75{
a1664773 76 struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
1da177e4 77 struct xfrm6_tunnel_spi *x6spi;
1da177e4 78
b67bfe0d 79 hlist_for_each_entry_rcu(x6spi,
a1664773 80 &xfrm6_tn->spi_byaddr[xfrm6_tunnel_spi_hash_byaddr(saddr)],
1da177e4 81 list_byaddr) {
ff88b30c 82 if (xfrm6_addr_equal(&x6spi->addr, saddr))
1da177e4 83 return x6spi;
1da177e4
LT
84 }
85
1da177e4
LT
86 return NULL;
87}
88
b71d1d42 89__be32 xfrm6_tunnel_spi_lookup(struct net *net, const xfrm_address_t *saddr)
1da177e4
LT
90{
91 struct xfrm6_tunnel_spi *x6spi;
92 u32 spi;
93
91cc3bb0 94 rcu_read_lock_bh();
a1664773 95 x6spi = __xfrm6_tunnel_spi_lookup(net, saddr);
1da177e4 96 spi = x6spi ? x6spi->spi : 0;
91cc3bb0 97 rcu_read_unlock_bh();
5b122545 98 return htonl(spi);
1da177e4 99}
1da177e4
LT
100EXPORT_SYMBOL(xfrm6_tunnel_spi_lookup);
101
a1664773 102static int __xfrm6_tunnel_spi_check(struct net *net, u32 spi)
df8ea19b 103{
a1664773 104 struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
df8ea19b
YH
105 struct xfrm6_tunnel_spi *x6spi;
106 int index = xfrm6_tunnel_spi_hash_byspi(spi);
df8ea19b 107
b67bfe0d 108 hlist_for_each_entry(x6spi,
a1664773 109 &xfrm6_tn->spi_byspi[index],
df8ea19b
YH
110 list_byspi) {
111 if (x6spi->spi == spi)
112 return -1;
113 }
114 return index;
115}
116
a1664773 117static u32 __xfrm6_tunnel_alloc_spi(struct net *net, xfrm_address_t *saddr)
1da177e4 118{
a1664773 119 struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
1da177e4
LT
120 u32 spi;
121 struct xfrm6_tunnel_spi *x6spi;
df8ea19b 122 int index;
1da177e4 123
a1664773
AD
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;
1da177e4 127 else
a1664773 128 xfrm6_tn->spi++;
1da177e4 129
a1664773
AD
130 for (spi = xfrm6_tn->spi; spi <= XFRM6_TUNNEL_SPI_MAX; spi++) {
131 index = __xfrm6_tunnel_spi_check(net, spi);
df8ea19b
YH
132 if (index >= 0)
133 goto alloc_spi;
fa89a459
Y
134
135 if (spi == XFRM6_TUNNEL_SPI_MAX)
136 break;
1da177e4 137 }
a1664773
AD
138 for (spi = XFRM6_TUNNEL_SPI_MIN; spi < xfrm6_tn->spi; spi++) {
139 index = __xfrm6_tunnel_spi_check(net, spi);
df8ea19b
YH
140 if (index >= 0)
141 goto alloc_spi;
1da177e4
LT
142 }
143 spi = 0;
144 goto out;
145alloc_spi:
a1664773 146 xfrm6_tn->spi = spi;
54e6ecb2 147 x6spi = kmem_cache_alloc(xfrm6_tunnel_spi_kmem, GFP_ATOMIC);
a922ba55 148 if (!x6spi)
1da177e4 149 goto out;
a922ba55 150
1da177e4
LT
151 memcpy(&x6spi->addr, saddr, sizeof(x6spi->addr));
152 x6spi->spi = spi;
d12f3827 153 refcount_set(&x6spi->refcnt, 1);
1da177e4 154
a1664773 155 hlist_add_head_rcu(&x6spi->list_byspi, &xfrm6_tn->spi_byspi[index]);
1da177e4
LT
156
157 index = xfrm6_tunnel_spi_hash_byaddr(saddr);
a1664773 158 hlist_add_head_rcu(&x6spi->list_byaddr, &xfrm6_tn->spi_byaddr[index]);
1da177e4 159out:
1da177e4
LT
160 return spi;
161}
162
a1664773 163__be32 xfrm6_tunnel_alloc_spi(struct net *net, xfrm_address_t *saddr)
1da177e4
LT
164{
165 struct xfrm6_tunnel_spi *x6spi;
166 u32 spi;
167
91cc3bb0 168 spin_lock_bh(&xfrm6_tunnel_spi_lock);
a1664773 169 x6spi = __xfrm6_tunnel_spi_lookup(net, saddr);
1da177e4 170 if (x6spi) {
d12f3827 171 refcount_inc(&x6spi->refcnt);
1da177e4
LT
172 spi = x6spi->spi;
173 } else
a1664773 174 spi = __xfrm6_tunnel_alloc_spi(net, saddr);
91cc3bb0 175 spin_unlock_bh(&xfrm6_tunnel_spi_lock);
1da177e4 176
5b122545 177 return htonl(spi);
1da177e4 178}
1da177e4
LT
179EXPORT_SYMBOL(xfrm6_tunnel_alloc_spi);
180
91cc3bb0
ED
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
6f747aca 187static void xfrm6_tunnel_free_spi(struct net *net, xfrm_address_t *saddr)
1da177e4 188{
a1664773 189 struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
1da177e4 190 struct xfrm6_tunnel_spi *x6spi;
b67bfe0d 191 struct hlist_node *n;
1da177e4 192
91cc3bb0 193 spin_lock_bh(&xfrm6_tunnel_spi_lock);
1da177e4 194
b67bfe0d 195 hlist_for_each_entry_safe(x6spi, n,
a1664773 196 &xfrm6_tn->spi_byaddr[xfrm6_tunnel_spi_hash_byaddr(saddr)],
1da177e4
LT
197 list_byaddr)
198 {
ff88b30c 199 if (xfrm6_addr_equal(&x6spi->addr, saddr)) {
d12f3827 200 if (refcount_dec_and_test(&x6spi->refcnt)) {
91cc3bb0
ED
201 hlist_del_rcu(&x6spi->list_byaddr);
202 hlist_del_rcu(&x6spi->list_byspi);
203 call_rcu(&x6spi->rcu_head, x6spi_destroy_rcu);
1da177e4
LT
204 break;
205 }
206 }
207 }
91cc3bb0 208 spin_unlock_bh(&xfrm6_tunnel_spi_lock);
1da177e4
LT
209}
210
1da177e4
LT
211static int xfrm6_tunnel_output(struct xfrm_state *x, struct sk_buff *skb)
212{
7b277b1a 213 skb_push(skb, -skb_network_offset(skb));
1da177e4
LT
214 return 0;
215}
216
e695633e 217static int xfrm6_tunnel_input(struct xfrm_state *x, struct sk_buff *skb)
1da177e4 218{
04663d0b 219 return skb_network_header(skb)[IP6CB(skb)->nhoff];
1da177e4
LT
220}
221
d2acc347 222static int xfrm6_tunnel_rcv(struct sk_buff *skb)
1da177e4 223{
a1664773 224 struct net *net = dev_net(skb->dev);
b71d1d42 225 const struct ipv6hdr *iph = ipv6_hdr(skb);
a252cc23 226 __be32 spi;
1da177e4 227
b71d1d42 228 spi = xfrm6_tunnel_spi_lookup(net, (const xfrm_address_t *)&iph->saddr);
63c43787 229 return xfrm6_rcv_spi(skb, IPPROTO_IPV6, spi, NULL);
1da177e4
LT
230}
231
d2acc347 232static int xfrm6_tunnel_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
d5fdd6ba 233 u8 type, u8 code, int offset, __be32 info)
1da177e4 234{
1da177e4
LT
235 /* xfrm6_tunnel native err handling */
236 switch (type) {
1ab1457c 237 case ICMPV6_DEST_UNREACH:
1da177e4 238 switch (code) {
1ab1457c 239 case ICMPV6_NOROUTE:
1da177e4
LT
240 case ICMPV6_ADM_PROHIBITED:
241 case ICMPV6_NOT_NEIGHBOUR:
242 case ICMPV6_ADDR_UNREACH:
243 case ICMPV6_PORT_UNREACH:
244 default:
1da177e4
LT
245 break;
246 }
247 break;
248 case ICMPV6_PKT_TOOBIG:
1da177e4
LT
249 break;
250 case ICMPV6_TIME_EXCEED:
251 switch (code) {
252 case ICMPV6_EXC_HOPLIMIT:
1da177e4
LT
253 break;
254 case ICMPV6_EXC_FRAGTIME:
1ab1457c 255 default:
1da177e4
LT
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 }
d2acc347
HX
269
270 return 0;
1da177e4
LT
271}
272
72cb6962 273static int xfrm6_tunnel_init_state(struct xfrm_state *x)
1da177e4 274{
7e49e6de 275 if (x->props.mode != XFRM_MODE_TUNNEL)
1da177e4
LT
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{
a1664773
AD
288 struct net *net = xs_net(x);
289
290 xfrm6_tunnel_free_spi(net, (xfrm_address_t *)&x->props.saddr);
1da177e4
LT
291}
292
533cb5b0 293static const struct xfrm_type xfrm6_tunnel_type = {
1da177e4
LT
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
3ff2cfa5 303static struct xfrm6_tunnel xfrm6_tunnel_handler __read_mostly = {
1da177e4 304 .handler = xfrm6_tunnel_rcv,
d2acc347
HX
305 .err_handler = xfrm6_tunnel_err,
306 .priority = 2,
1da177e4
LT
307};
308
3ff2cfa5 309static struct xfrm6_tunnel xfrm46_tunnel_handler __read_mostly = {
73d605d1
KM
310 .handler = xfrm6_tunnel_rcv,
311 .err_handler = xfrm6_tunnel_err,
312 .priority = 2,
313};
314
a1664773
AD
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{
baeb0dbb
VA
331 struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
332 unsigned int i;
333
b48c05ab 334 xfrm_flush_gc();
dbb2483b 335 xfrm_state_flush(net, 0, false, true);
b48c05ab 336
baeb0dbb
VA
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]));
a1664773
AD
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
1da177e4
LT
351static int __init xfrm6_tunnel_init(void)
352{
e924960d
AD
353 int rv;
354
d5aa407f
AD
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;
e924960d
AD
364 rv = xfrm_register_type(&xfrm6_tunnel_type, AF_INET6);
365 if (rv < 0)
d5aa407f 366 goto out_type;
e924960d
AD
367 rv = xfrm6_tunnel_register(&xfrm6_tunnel_handler, AF_INET6);
368 if (rv < 0)
d5aa407f 369 goto out_xfrm6;
e924960d
AD
370 rv = xfrm6_tunnel_register(&xfrm46_tunnel_handler, AF_INET);
371 if (rv < 0)
d5aa407f 372 goto out_xfrm46;
1da177e4 373 return 0;
5ce1bbb9 374
d5aa407f 375out_xfrm46:
5ce1bbb9 376 xfrm6_tunnel_deregister(&xfrm6_tunnel_handler, AF_INET6);
d5aa407f 377out_xfrm6:
5ce1bbb9 378 xfrm_unregister_type(&xfrm6_tunnel_type, AF_INET6);
d5aa407f
AD
379out_type:
380 unregister_pernet_subsys(&xfrm6_tunnel_net_ops);
381out_pernet:
382 kmem_cache_destroy(xfrm6_tunnel_spi_kmem);
e924960d 383 return rv;
1da177e4
LT
384}
385
386static void __exit xfrm6_tunnel_fini(void)
387{
73d605d1
KM
388 xfrm6_tunnel_deregister(&xfrm46_tunnel_handler, AF_INET);
389 xfrm6_tunnel_deregister(&xfrm6_tunnel_handler, AF_INET6);
a922ba55 390 xfrm_unregister_type(&xfrm6_tunnel_type, AF_INET6);
d5aa407f 391 unregister_pernet_subsys(&xfrm6_tunnel_net_ops);
6ee02a54
SY
392 /* Someone maybe has gotten the xfrm6_tunnel_spi.
393 * So need to wait it.
394 */
395 rcu_barrier();
d5aa407f 396 kmem_cache_destroy(xfrm6_tunnel_spi_kmem);
1da177e4
LT
397}
398
399module_init(xfrm6_tunnel_init);
400module_exit(xfrm6_tunnel_fini);
401MODULE_LICENSE("GPL");
d3d6dd3a 402MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_IPV6);