diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
---|---|---|
committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /net/ipv6/ipcomp6.c |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'net/ipv6/ipcomp6.c')
-rw-r--r-- | net/ipv6/ipcomp6.c | 524 |
1 files changed, 524 insertions, 0 deletions
diff --git a/net/ipv6/ipcomp6.c b/net/ipv6/ipcomp6.c new file mode 100644 index 000000000000..6cde5310cd76 --- /dev/null +++ b/net/ipv6/ipcomp6.c | |||
@@ -0,0 +1,524 @@ | |||
1 | /* | ||
2 | * IP Payload Compression Protocol (IPComp) for IPv6 - RFC3173 | ||
3 | * | ||
4 | * Copyright (C)2003 USAGI/WIDE Project | ||
5 | * | ||
6 | * Author Mitsuru KANDA <mk@linux-ipv6.org> | ||
7 | * | ||
8 | * This program is free software; you can redistribute it and/or modify | ||
9 | * it under the terms of the GNU General Public License as published by | ||
10 | * the Free Software Foundation; either version 2 of the License, or | ||
11 | * (at your option) any later version. | ||
12 | * | ||
13 | * This program is distributed in the hope that it will be useful, | ||
14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||
16 | * GNU General Public License for more details. | ||
17 | * | ||
18 | * You should have received a copy of the GNU General Public License | ||
19 | * along with this program; if not, write to the Free Software | ||
20 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | ||
21 | */ | ||
22 | /* | ||
23 | * [Memo] | ||
24 | * | ||
25 | * Outbound: | ||
26 | * The compression of IP datagram MUST be done before AH/ESP processing, | ||
27 | * fragmentation, and the addition of Hop-by-Hop/Routing header. | ||
28 | * | ||
29 | * Inbound: | ||
30 | * The decompression of IP datagram MUST be done after the reassembly, | ||
31 | * AH/ESP processing. | ||
32 | */ | ||
33 | #include <linux/config.h> | ||
34 | #include <linux/module.h> | ||
35 | #include <net/ip.h> | ||
36 | #include <net/xfrm.h> | ||
37 | #include <net/ipcomp.h> | ||
38 | #include <asm/scatterlist.h> | ||
39 | #include <asm/semaphore.h> | ||
40 | #include <linux/crypto.h> | ||
41 | #include <linux/pfkeyv2.h> | ||
42 | #include <linux/random.h> | ||
43 | #include <linux/percpu.h> | ||
44 | #include <linux/smp.h> | ||
45 | #include <linux/list.h> | ||
46 | #include <linux/vmalloc.h> | ||
47 | #include <linux/rtnetlink.h> | ||
48 | #include <net/icmp.h> | ||
49 | #include <net/ipv6.h> | ||
50 | #include <linux/ipv6.h> | ||
51 | #include <linux/icmpv6.h> | ||
52 | |||
53 | struct ipcomp6_tfms { | ||
54 | struct list_head list; | ||
55 | struct crypto_tfm **tfms; | ||
56 | int users; | ||
57 | }; | ||
58 | |||
59 | static DECLARE_MUTEX(ipcomp6_resource_sem); | ||
60 | static void **ipcomp6_scratches; | ||
61 | static int ipcomp6_scratch_users; | ||
62 | static LIST_HEAD(ipcomp6_tfms_list); | ||
63 | |||
64 | static int ipcomp6_input(struct xfrm_state *x, struct xfrm_decap_state *decap, struct sk_buff *skb) | ||
65 | { | ||
66 | int err = 0; | ||
67 | u8 nexthdr = 0; | ||
68 | int hdr_len = skb->h.raw - skb->nh.raw; | ||
69 | unsigned char *tmp_hdr = NULL; | ||
70 | struct ipv6hdr *iph; | ||
71 | int plen, dlen; | ||
72 | struct ipcomp_data *ipcd = x->data; | ||
73 | u8 *start, *scratch; | ||
74 | struct crypto_tfm *tfm; | ||
75 | int cpu; | ||
76 | |||
77 | if ((skb_is_nonlinear(skb) || skb_cloned(skb)) && | ||
78 | skb_linearize(skb, GFP_ATOMIC) != 0) { | ||
79 | err = -ENOMEM; | ||
80 | goto out; | ||
81 | } | ||
82 | |||
83 | skb->ip_summed = CHECKSUM_NONE; | ||
84 | |||
85 | /* Remove ipcomp header and decompress original payload */ | ||
86 | iph = skb->nh.ipv6h; | ||
87 | tmp_hdr = kmalloc(hdr_len, GFP_ATOMIC); | ||
88 | if (!tmp_hdr) | ||
89 | goto out; | ||
90 | memcpy(tmp_hdr, iph, hdr_len); | ||
91 | nexthdr = *(u8 *)skb->data; | ||
92 | skb_pull(skb, sizeof(struct ipv6_comp_hdr)); | ||
93 | skb->nh.raw += sizeof(struct ipv6_comp_hdr); | ||
94 | memcpy(skb->nh.raw, tmp_hdr, hdr_len); | ||
95 | iph = skb->nh.ipv6h; | ||
96 | iph->payload_len = htons(ntohs(iph->payload_len) - sizeof(struct ipv6_comp_hdr)); | ||
97 | skb->h.raw = skb->data; | ||
98 | |||
99 | /* decompression */ | ||
100 | plen = skb->len; | ||
101 | dlen = IPCOMP_SCRATCH_SIZE; | ||
102 | start = skb->data; | ||
103 | |||
104 | cpu = get_cpu(); | ||
105 | scratch = *per_cpu_ptr(ipcomp6_scratches, cpu); | ||
106 | tfm = *per_cpu_ptr(ipcd->tfms, cpu); | ||
107 | |||
108 | err = crypto_comp_decompress(tfm, start, plen, scratch, &dlen); | ||
109 | if (err) { | ||
110 | err = -EINVAL; | ||
111 | goto out_put_cpu; | ||
112 | } | ||
113 | |||
114 | if (dlen < (plen + sizeof(struct ipv6_comp_hdr))) { | ||
115 | err = -EINVAL; | ||
116 | goto out_put_cpu; | ||
117 | } | ||
118 | |||
119 | err = pskb_expand_head(skb, 0, dlen - plen, GFP_ATOMIC); | ||
120 | if (err) { | ||
121 | goto out_put_cpu; | ||
122 | } | ||
123 | |||
124 | skb_put(skb, dlen - plen); | ||
125 | memcpy(skb->data, scratch, dlen); | ||
126 | |||
127 | iph = skb->nh.ipv6h; | ||
128 | iph->payload_len = htons(skb->len); | ||
129 | |||
130 | out_put_cpu: | ||
131 | put_cpu(); | ||
132 | out: | ||
133 | if (tmp_hdr) | ||
134 | kfree(tmp_hdr); | ||
135 | if (err) | ||
136 | goto error_out; | ||
137 | return nexthdr; | ||
138 | error_out: | ||
139 | return err; | ||
140 | } | ||
141 | |||
142 | static int ipcomp6_output(struct xfrm_state *x, struct sk_buff *skb) | ||
143 | { | ||
144 | int err; | ||
145 | struct ipv6hdr *top_iph; | ||
146 | int hdr_len; | ||
147 | struct ipv6_comp_hdr *ipch; | ||
148 | struct ipcomp_data *ipcd = x->data; | ||
149 | int plen, dlen; | ||
150 | u8 *start, *scratch; | ||
151 | struct crypto_tfm *tfm; | ||
152 | int cpu; | ||
153 | |||
154 | hdr_len = skb->h.raw - skb->data; | ||
155 | |||
156 | /* check whether datagram len is larger than threshold */ | ||
157 | if ((skb->len - hdr_len) < ipcd->threshold) { | ||
158 | goto out_ok; | ||
159 | } | ||
160 | |||
161 | if ((skb_is_nonlinear(skb) || skb_cloned(skb)) && | ||
162 | skb_linearize(skb, GFP_ATOMIC) != 0) { | ||
163 | goto out_ok; | ||
164 | } | ||
165 | |||
166 | /* compression */ | ||
167 | plen = skb->len - hdr_len; | ||
168 | dlen = IPCOMP_SCRATCH_SIZE; | ||
169 | start = skb->h.raw; | ||
170 | |||
171 | cpu = get_cpu(); | ||
172 | scratch = *per_cpu_ptr(ipcomp6_scratches, cpu); | ||
173 | tfm = *per_cpu_ptr(ipcd->tfms, cpu); | ||
174 | |||
175 | err = crypto_comp_compress(tfm, start, plen, scratch, &dlen); | ||
176 | if (err || (dlen + sizeof(struct ipv6_comp_hdr)) >= plen) { | ||
177 | put_cpu(); | ||
178 | goto out_ok; | ||
179 | } | ||
180 | memcpy(start + sizeof(struct ip_comp_hdr), scratch, dlen); | ||
181 | put_cpu(); | ||
182 | pskb_trim(skb, hdr_len + dlen + sizeof(struct ip_comp_hdr)); | ||
183 | |||
184 | /* insert ipcomp header and replace datagram */ | ||
185 | top_iph = (struct ipv6hdr *)skb->data; | ||
186 | |||
187 | top_iph->payload_len = htons(skb->len - sizeof(struct ipv6hdr)); | ||
188 | |||
189 | ipch = (struct ipv6_comp_hdr *)start; | ||
190 | ipch->nexthdr = *skb->nh.raw; | ||
191 | ipch->flags = 0; | ||
192 | ipch->cpi = htons((u16 )ntohl(x->id.spi)); | ||
193 | *skb->nh.raw = IPPROTO_COMP; | ||
194 | |||
195 | out_ok: | ||
196 | return 0; | ||
197 | } | ||
198 | |||
199 | static void ipcomp6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, | ||
200 | int type, int code, int offset, __u32 info) | ||
201 | { | ||
202 | u32 spi; | ||
203 | struct ipv6hdr *iph = (struct ipv6hdr*)skb->data; | ||
204 | struct ipv6_comp_hdr *ipcomph = (struct ipv6_comp_hdr*)(skb->data+offset); | ||
205 | struct xfrm_state *x; | ||
206 | |||
207 | if (type != ICMPV6_DEST_UNREACH && type != ICMPV6_PKT_TOOBIG) | ||
208 | return; | ||
209 | |||
210 | spi = ntohl(ntohs(ipcomph->cpi)); | ||
211 | x = xfrm_state_lookup((xfrm_address_t *)&iph->daddr, spi, IPPROTO_COMP, AF_INET6); | ||
212 | if (!x) | ||
213 | return; | ||
214 | |||
215 | printk(KERN_DEBUG "pmtu discovery on SA IPCOMP/%08x/" | ||
216 | "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n", | ||
217 | spi, NIP6(iph->daddr)); | ||
218 | xfrm_state_put(x); | ||
219 | } | ||
220 | |||
221 | static struct xfrm_state *ipcomp6_tunnel_create(struct xfrm_state *x) | ||
222 | { | ||
223 | struct xfrm_state *t = NULL; | ||
224 | |||
225 | t = xfrm_state_alloc(); | ||
226 | if (!t) | ||
227 | goto out; | ||
228 | |||
229 | t->id.proto = IPPROTO_IPV6; | ||
230 | t->id.spi = xfrm6_tunnel_alloc_spi((xfrm_address_t *)&x->props.saddr); | ||
231 | memcpy(t->id.daddr.a6, x->id.daddr.a6, sizeof(struct in6_addr)); | ||
232 | memcpy(&t->sel, &x->sel, sizeof(t->sel)); | ||
233 | t->props.family = AF_INET6; | ||
234 | t->props.mode = 1; | ||
235 | memcpy(t->props.saddr.a6, x->props.saddr.a6, sizeof(struct in6_addr)); | ||
236 | |||
237 | t->type = xfrm_get_type(IPPROTO_IPV6, t->props.family); | ||
238 | if (t->type == NULL) | ||
239 | goto error; | ||
240 | |||
241 | if (t->type->init_state(t, NULL)) | ||
242 | goto error; | ||
243 | |||
244 | t->km.state = XFRM_STATE_VALID; | ||
245 | atomic_set(&t->tunnel_users, 1); | ||
246 | |||
247 | out: | ||
248 | return t; | ||
249 | |||
250 | error: | ||
251 | xfrm_state_put(t); | ||
252 | goto out; | ||
253 | } | ||
254 | |||
255 | static int ipcomp6_tunnel_attach(struct xfrm_state *x) | ||
256 | { | ||
257 | int err = 0; | ||
258 | struct xfrm_state *t = NULL; | ||
259 | u32 spi; | ||
260 | |||
261 | spi = xfrm6_tunnel_spi_lookup((xfrm_address_t *)&x->props.saddr); | ||
262 | if (spi) | ||
263 | t = xfrm_state_lookup((xfrm_address_t *)&x->id.daddr, | ||
264 | spi, IPPROTO_IPV6, AF_INET6); | ||
265 | if (!t) { | ||
266 | t = ipcomp6_tunnel_create(x); | ||
267 | if (!t) { | ||
268 | err = -EINVAL; | ||
269 | goto out; | ||
270 | } | ||
271 | xfrm_state_insert(t); | ||
272 | xfrm_state_hold(t); | ||
273 | } | ||
274 | x->tunnel = t; | ||
275 | atomic_inc(&t->tunnel_users); | ||
276 | |||
277 | out: | ||
278 | return err; | ||
279 | } | ||
280 | |||
281 | static void ipcomp6_free_scratches(void) | ||
282 | { | ||
283 | int i; | ||
284 | void **scratches; | ||
285 | |||
286 | if (--ipcomp6_scratch_users) | ||
287 | return; | ||
288 | |||
289 | scratches = ipcomp6_scratches; | ||
290 | if (!scratches) | ||
291 | return; | ||
292 | |||
293 | for_each_cpu(i) { | ||
294 | void *scratch = *per_cpu_ptr(scratches, i); | ||
295 | if (scratch) | ||
296 | vfree(scratch); | ||
297 | } | ||
298 | |||
299 | free_percpu(scratches); | ||
300 | } | ||
301 | |||
302 | static void **ipcomp6_alloc_scratches(void) | ||
303 | { | ||
304 | int i; | ||
305 | void **scratches; | ||
306 | |||
307 | if (ipcomp6_scratch_users++) | ||
308 | return ipcomp6_scratches; | ||
309 | |||
310 | scratches = alloc_percpu(void *); | ||
311 | if (!scratches) | ||
312 | return NULL; | ||
313 | |||
314 | ipcomp6_scratches = scratches; | ||
315 | |||
316 | for_each_cpu(i) { | ||
317 | void *scratch = vmalloc(IPCOMP_SCRATCH_SIZE); | ||
318 | if (!scratch) | ||
319 | return NULL; | ||
320 | *per_cpu_ptr(scratches, i) = scratch; | ||
321 | } | ||
322 | |||
323 | return scratches; | ||
324 | } | ||
325 | |||
326 | static void ipcomp6_free_tfms(struct crypto_tfm **tfms) | ||
327 | { | ||
328 | struct ipcomp6_tfms *pos; | ||
329 | int cpu; | ||
330 | |||
331 | list_for_each_entry(pos, &ipcomp6_tfms_list, list) { | ||
332 | if (pos->tfms == tfms) | ||
333 | break; | ||
334 | } | ||
335 | |||
336 | BUG_TRAP(pos); | ||
337 | |||
338 | if (--pos->users) | ||
339 | return; | ||
340 | |||
341 | list_del(&pos->list); | ||
342 | kfree(pos); | ||
343 | |||
344 | if (!tfms) | ||
345 | return; | ||
346 | |||
347 | for_each_cpu(cpu) { | ||
348 | struct crypto_tfm *tfm = *per_cpu_ptr(tfms, cpu); | ||
349 | if (tfm) | ||
350 | crypto_free_tfm(tfm); | ||
351 | } | ||
352 | free_percpu(tfms); | ||
353 | } | ||
354 | |||
355 | static struct crypto_tfm **ipcomp6_alloc_tfms(const char *alg_name) | ||
356 | { | ||
357 | struct ipcomp6_tfms *pos; | ||
358 | struct crypto_tfm **tfms; | ||
359 | int cpu; | ||
360 | |||
361 | /* This can be any valid CPU ID so we don't need locking. */ | ||
362 | cpu = smp_processor_id(); | ||
363 | |||
364 | list_for_each_entry(pos, &ipcomp6_tfms_list, list) { | ||
365 | struct crypto_tfm *tfm; | ||
366 | |||
367 | tfms = pos->tfms; | ||
368 | tfm = *per_cpu_ptr(tfms, cpu); | ||
369 | |||
370 | if (!strcmp(crypto_tfm_alg_name(tfm), alg_name)) { | ||
371 | pos->users++; | ||
372 | return tfms; | ||
373 | } | ||
374 | } | ||
375 | |||
376 | pos = kmalloc(sizeof(*pos), GFP_KERNEL); | ||
377 | if (!pos) | ||
378 | return NULL; | ||
379 | |||
380 | pos->users = 1; | ||
381 | INIT_LIST_HEAD(&pos->list); | ||
382 | list_add(&pos->list, &ipcomp6_tfms_list); | ||
383 | |||
384 | pos->tfms = tfms = alloc_percpu(struct crypto_tfm *); | ||
385 | if (!tfms) | ||
386 | goto error; | ||
387 | |||
388 | for_each_cpu(cpu) { | ||
389 | struct crypto_tfm *tfm = crypto_alloc_tfm(alg_name, 0); | ||
390 | if (!tfm) | ||
391 | goto error; | ||
392 | *per_cpu_ptr(tfms, cpu) = tfm; | ||
393 | } | ||
394 | |||
395 | return tfms; | ||
396 | |||
397 | error: | ||
398 | ipcomp6_free_tfms(tfms); | ||
399 | return NULL; | ||
400 | } | ||
401 | |||
402 | static void ipcomp6_free_data(struct ipcomp_data *ipcd) | ||
403 | { | ||
404 | if (ipcd->tfms) | ||
405 | ipcomp6_free_tfms(ipcd->tfms); | ||
406 | ipcomp6_free_scratches(); | ||
407 | } | ||
408 | |||
409 | static void ipcomp6_destroy(struct xfrm_state *x) | ||
410 | { | ||
411 | struct ipcomp_data *ipcd = x->data; | ||
412 | if (!ipcd) | ||
413 | return; | ||
414 | xfrm_state_delete_tunnel(x); | ||
415 | down(&ipcomp6_resource_sem); | ||
416 | ipcomp6_free_data(ipcd); | ||
417 | up(&ipcomp6_resource_sem); | ||
418 | kfree(ipcd); | ||
419 | |||
420 | xfrm6_tunnel_free_spi((xfrm_address_t *)&x->props.saddr); | ||
421 | } | ||
422 | |||
423 | static int ipcomp6_init_state(struct xfrm_state *x, void *args) | ||
424 | { | ||
425 | int err; | ||
426 | struct ipcomp_data *ipcd; | ||
427 | struct xfrm_algo_desc *calg_desc; | ||
428 | |||
429 | err = -EINVAL; | ||
430 | if (!x->calg) | ||
431 | goto out; | ||
432 | |||
433 | if (x->encap) | ||
434 | goto out; | ||
435 | |||
436 | err = -ENOMEM; | ||
437 | ipcd = kmalloc(sizeof(*ipcd), GFP_KERNEL); | ||
438 | if (!ipcd) | ||
439 | goto out; | ||
440 | |||
441 | memset(ipcd, 0, sizeof(*ipcd)); | ||
442 | x->props.header_len = 0; | ||
443 | if (x->props.mode) | ||
444 | x->props.header_len += sizeof(struct ipv6hdr); | ||
445 | |||
446 | down(&ipcomp6_resource_sem); | ||
447 | if (!ipcomp6_alloc_scratches()) | ||
448 | goto error; | ||
449 | |||
450 | ipcd->tfms = ipcomp6_alloc_tfms(x->calg->alg_name); | ||
451 | if (!ipcd->tfms) | ||
452 | goto error; | ||
453 | up(&ipcomp6_resource_sem); | ||
454 | |||
455 | if (x->props.mode) { | ||
456 | err = ipcomp6_tunnel_attach(x); | ||
457 | if (err) | ||
458 | goto error_tunnel; | ||
459 | } | ||
460 | |||
461 | calg_desc = xfrm_calg_get_byname(x->calg->alg_name, 0); | ||
462 | BUG_ON(!calg_desc); | ||
463 | ipcd->threshold = calg_desc->uinfo.comp.threshold; | ||
464 | x->data = ipcd; | ||
465 | err = 0; | ||
466 | out: | ||
467 | return err; | ||
468 | error_tunnel: | ||
469 | down(&ipcomp6_resource_sem); | ||
470 | error: | ||
471 | ipcomp6_free_data(ipcd); | ||
472 | up(&ipcomp6_resource_sem); | ||
473 | kfree(ipcd); | ||
474 | |||
475 | goto out; | ||
476 | } | ||
477 | |||
478 | static struct xfrm_type ipcomp6_type = | ||
479 | { | ||
480 | .description = "IPCOMP6", | ||
481 | .owner = THIS_MODULE, | ||
482 | .proto = IPPROTO_COMP, | ||
483 | .init_state = ipcomp6_init_state, | ||
484 | .destructor = ipcomp6_destroy, | ||
485 | .input = ipcomp6_input, | ||
486 | .output = ipcomp6_output, | ||
487 | }; | ||
488 | |||
489 | static struct inet6_protocol ipcomp6_protocol = | ||
490 | { | ||
491 | .handler = xfrm6_rcv, | ||
492 | .err_handler = ipcomp6_err, | ||
493 | .flags = INET6_PROTO_NOPOLICY, | ||
494 | }; | ||
495 | |||
496 | static int __init ipcomp6_init(void) | ||
497 | { | ||
498 | if (xfrm_register_type(&ipcomp6_type, AF_INET6) < 0) { | ||
499 | printk(KERN_INFO "ipcomp6 init: can't add xfrm type\n"); | ||
500 | return -EAGAIN; | ||
501 | } | ||
502 | if (inet6_add_protocol(&ipcomp6_protocol, IPPROTO_COMP) < 0) { | ||
503 | printk(KERN_INFO "ipcomp6 init: can't add protocol\n"); | ||
504 | xfrm_unregister_type(&ipcomp6_type, AF_INET6); | ||
505 | return -EAGAIN; | ||
506 | } | ||
507 | return 0; | ||
508 | } | ||
509 | |||
510 | static void __exit ipcomp6_fini(void) | ||
511 | { | ||
512 | if (inet6_del_protocol(&ipcomp6_protocol, IPPROTO_COMP) < 0) | ||
513 | printk(KERN_INFO "ipv6 ipcomp close: can't remove protocol\n"); | ||
514 | if (xfrm_unregister_type(&ipcomp6_type, AF_INET6) < 0) | ||
515 | printk(KERN_INFO "ipv6 ipcomp close: can't remove xfrm type\n"); | ||
516 | } | ||
517 | |||
518 | module_init(ipcomp6_init); | ||
519 | module_exit(ipcomp6_fini); | ||
520 | MODULE_LICENSE("GPL"); | ||
521 | MODULE_DESCRIPTION("IP Payload Compression Protocol (IPComp) for IPv6 - RFC3173"); | ||
522 | MODULE_AUTHOR("Mitsuru KANDA <mk@linux-ipv6.org>"); | ||
523 | |||
524 | |||