ia64/linux-2.6.18-xen.hg

view net/ipv6/ipcomp6.c @ 673:3161879fdf22

[IA64] xencomm: support XENMEM_add_to_physmap and XENMEM_remove_from_phsymap

support XENMEM_add_to_physmap and XENMEM_remove_from_phsymap.

Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
author Isaku Yamahata <yamahata@valinux.co.jp>
date Tue Sep 16 21:26:15 2008 +0900 (2008-09-16)
parents 831230e53067
children
line source
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/module.h>
34 #include <net/ip.h>
35 #include <net/xfrm.h>
36 #include <net/ipcomp.h>
37 #include <asm/scatterlist.h>
38 #include <asm/semaphore.h>
39 #include <linux/crypto.h>
40 #include <linux/pfkeyv2.h>
41 #include <linux/random.h>
42 #include <linux/percpu.h>
43 #include <linux/smp.h>
44 #include <linux/list.h>
45 #include <linux/vmalloc.h>
46 #include <linux/rtnetlink.h>
47 #include <net/icmp.h>
48 #include <net/ipv6.h>
49 #include <net/protocol.h>
50 #include <linux/ipv6.h>
51 #include <linux/icmpv6.h>
52 #include <linux/mutex.h>
54 struct ipcomp6_tfms {
55 struct list_head list;
56 struct crypto_tfm **tfms;
57 int users;
58 };
60 static DEFINE_MUTEX(ipcomp6_resource_mutex);
61 static void **ipcomp6_scratches;
62 static int ipcomp6_scratch_users;
63 static LIST_HEAD(ipcomp6_tfms_list);
65 static int ipcomp6_input(struct xfrm_state *x, struct sk_buff *skb)
66 {
67 int err = -ENOMEM;
68 struct ipv6hdr *iph;
69 struct ipv6_comp_hdr *ipch;
70 int plen, dlen;
71 struct ipcomp_data *ipcd = x->data;
72 u8 *start, *scratch;
73 struct crypto_tfm *tfm;
74 int cpu;
76 if (skb_linearize_cow(skb))
77 goto out;
79 skb->ip_summed = CHECKSUM_NONE;
81 /* Remove ipcomp header and decompress original payload */
82 iph = skb->nh.ipv6h;
83 ipch = (void *)skb->data;
84 skb->h.raw = skb->nh.raw + sizeof(*ipch);
85 __skb_pull(skb, sizeof(*ipch));
87 /* decompression */
88 plen = skb->len;
89 dlen = IPCOMP_SCRATCH_SIZE;
90 start = skb->data;
92 cpu = get_cpu();
93 scratch = *per_cpu_ptr(ipcomp6_scratches, cpu);
94 tfm = *per_cpu_ptr(ipcd->tfms, cpu);
96 err = crypto_comp_decompress(tfm, start, plen, scratch, &dlen);
97 if (err) {
98 err = -EINVAL;
99 goto out_put_cpu;
100 }
102 if (dlen < (plen + sizeof(struct ipv6_comp_hdr))) {
103 err = -EINVAL;
104 goto out_put_cpu;
105 }
107 err = pskb_expand_head(skb, 0, dlen - plen, GFP_ATOMIC);
108 if (err) {
109 goto out_put_cpu;
110 }
112 skb->truesize += dlen - plen;
113 __skb_put(skb, dlen - plen);
114 memcpy(skb->data, scratch, dlen);
115 err = ipch->nexthdr;
117 out_put_cpu:
118 put_cpu();
119 out:
120 return err;
121 }
123 static int ipcomp6_output(struct xfrm_state *x, struct sk_buff *skb)
124 {
125 int err;
126 struct ipv6hdr *top_iph;
127 int hdr_len;
128 struct ipv6_comp_hdr *ipch;
129 struct ipcomp_data *ipcd = x->data;
130 int plen, dlen;
131 u8 *start, *scratch;
132 struct crypto_tfm *tfm;
133 int cpu;
135 hdr_len = skb->h.raw - skb->data;
137 /* check whether datagram len is larger than threshold */
138 if ((skb->len - hdr_len) < ipcd->threshold) {
139 goto out_ok;
140 }
142 if (skb_linearize_cow(skb))
143 goto out_ok;
145 /* compression */
146 plen = skb->len - hdr_len;
147 dlen = IPCOMP_SCRATCH_SIZE;
148 start = skb->h.raw;
150 cpu = get_cpu();
151 scratch = *per_cpu_ptr(ipcomp6_scratches, cpu);
152 tfm = *per_cpu_ptr(ipcd->tfms, cpu);
154 err = crypto_comp_compress(tfm, start, plen, scratch, &dlen);
155 if (err || (dlen + sizeof(struct ipv6_comp_hdr)) >= plen) {
156 put_cpu();
157 goto out_ok;
158 }
159 memcpy(start + sizeof(struct ip_comp_hdr), scratch, dlen);
160 put_cpu();
161 pskb_trim(skb, hdr_len + dlen + sizeof(struct ip_comp_hdr));
163 /* insert ipcomp header and replace datagram */
164 top_iph = (struct ipv6hdr *)skb->data;
166 top_iph->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
168 ipch = (struct ipv6_comp_hdr *)start;
169 ipch->nexthdr = *skb->nh.raw;
170 ipch->flags = 0;
171 ipch->cpi = htons((u16 )ntohl(x->id.spi));
172 *skb->nh.raw = IPPROTO_COMP;
174 out_ok:
175 return 0;
176 }
178 static void ipcomp6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
179 int type, int code, int offset, __u32 info)
180 {
181 u32 spi;
182 struct ipv6hdr *iph = (struct ipv6hdr*)skb->data;
183 struct ipv6_comp_hdr *ipcomph = (struct ipv6_comp_hdr*)(skb->data+offset);
184 struct xfrm_state *x;
186 if (type != ICMPV6_DEST_UNREACH && type != ICMPV6_PKT_TOOBIG)
187 return;
189 spi = htonl(ntohs(ipcomph->cpi));
190 x = xfrm_state_lookup((xfrm_address_t *)&iph->daddr, spi, IPPROTO_COMP, AF_INET6);
191 if (!x)
192 return;
194 printk(KERN_DEBUG "pmtu discovery on SA IPCOMP/%08x/" NIP6_FMT "\n",
195 spi, NIP6(iph->daddr));
196 xfrm_state_put(x);
197 }
199 static struct xfrm_state *ipcomp6_tunnel_create(struct xfrm_state *x)
200 {
201 struct xfrm_state *t = NULL;
203 t = xfrm_state_alloc();
204 if (!t)
205 goto out;
207 t->id.proto = IPPROTO_IPV6;
208 t->id.spi = xfrm6_tunnel_alloc_spi((xfrm_address_t *)&x->props.saddr);
209 if (!t->id.spi)
210 goto error;
212 memcpy(t->id.daddr.a6, x->id.daddr.a6, sizeof(struct in6_addr));
213 memcpy(&t->sel, &x->sel, sizeof(t->sel));
214 t->props.family = AF_INET6;
215 t->props.mode = 1;
216 memcpy(t->props.saddr.a6, x->props.saddr.a6, sizeof(struct in6_addr));
218 if (xfrm_init_state(t))
219 goto error;
221 atomic_set(&t->tunnel_users, 1);
223 out:
224 return t;
226 error:
227 t->km.state = XFRM_STATE_DEAD;
228 xfrm_state_put(t);
229 t = NULL;
230 goto out;
231 }
233 static int ipcomp6_tunnel_attach(struct xfrm_state *x)
234 {
235 int err = 0;
236 struct xfrm_state *t = NULL;
237 u32 spi;
239 spi = xfrm6_tunnel_spi_lookup((xfrm_address_t *)&x->props.saddr);
240 if (spi)
241 t = xfrm_state_lookup((xfrm_address_t *)&x->id.daddr,
242 spi, IPPROTO_IPV6, AF_INET6);
243 if (!t) {
244 t = ipcomp6_tunnel_create(x);
245 if (!t) {
246 err = -EINVAL;
247 goto out;
248 }
249 xfrm_state_insert(t);
250 xfrm_state_hold(t);
251 }
252 x->tunnel = t;
253 atomic_inc(&t->tunnel_users);
255 out:
256 return err;
257 }
259 static void ipcomp6_free_scratches(void)
260 {
261 int i;
262 void **scratches;
264 if (--ipcomp6_scratch_users)
265 return;
267 scratches = ipcomp6_scratches;
268 if (!scratches)
269 return;
271 for_each_possible_cpu(i) {
272 void *scratch = *per_cpu_ptr(scratches, i);
274 vfree(scratch);
275 }
277 free_percpu(scratches);
278 }
280 static void **ipcomp6_alloc_scratches(void)
281 {
282 int i;
283 void **scratches;
285 if (ipcomp6_scratch_users++)
286 return ipcomp6_scratches;
288 scratches = alloc_percpu(void *);
289 if (!scratches)
290 return NULL;
292 ipcomp6_scratches = scratches;
294 for_each_possible_cpu(i) {
295 void *scratch = vmalloc(IPCOMP_SCRATCH_SIZE);
296 if (!scratch)
297 return NULL;
298 *per_cpu_ptr(scratches, i) = scratch;
299 }
301 return scratches;
302 }
304 static void ipcomp6_free_tfms(struct crypto_tfm **tfms)
305 {
306 struct ipcomp6_tfms *pos;
307 int cpu;
309 list_for_each_entry(pos, &ipcomp6_tfms_list, list) {
310 if (pos->tfms == tfms)
311 break;
312 }
314 BUG_TRAP(pos);
316 if (--pos->users)
317 return;
319 list_del(&pos->list);
320 kfree(pos);
322 if (!tfms)
323 return;
325 for_each_possible_cpu(cpu) {
326 struct crypto_tfm *tfm = *per_cpu_ptr(tfms, cpu);
327 crypto_free_tfm(tfm);
328 }
329 free_percpu(tfms);
330 }
332 static struct crypto_tfm **ipcomp6_alloc_tfms(const char *alg_name)
333 {
334 struct ipcomp6_tfms *pos;
335 struct crypto_tfm **tfms;
336 int cpu;
338 /* This can be any valid CPU ID so we don't need locking. */
339 cpu = raw_smp_processor_id();
341 list_for_each_entry(pos, &ipcomp6_tfms_list, list) {
342 struct crypto_tfm *tfm;
344 tfms = pos->tfms;
345 tfm = *per_cpu_ptr(tfms, cpu);
347 if (!strcmp(crypto_tfm_alg_name(tfm), alg_name)) {
348 pos->users++;
349 return tfms;
350 }
351 }
353 pos = kmalloc(sizeof(*pos), GFP_KERNEL);
354 if (!pos)
355 return NULL;
357 pos->users = 1;
358 INIT_LIST_HEAD(&pos->list);
359 list_add(&pos->list, &ipcomp6_tfms_list);
361 pos->tfms = tfms = alloc_percpu(struct crypto_tfm *);
362 if (!tfms)
363 goto error;
365 for_each_possible_cpu(cpu) {
366 struct crypto_tfm *tfm = crypto_alloc_tfm(alg_name, 0);
367 if (!tfm)
368 goto error;
369 *per_cpu_ptr(tfms, cpu) = tfm;
370 }
372 return tfms;
374 error:
375 ipcomp6_free_tfms(tfms);
376 return NULL;
377 }
379 static void ipcomp6_free_data(struct ipcomp_data *ipcd)
380 {
381 if (ipcd->tfms)
382 ipcomp6_free_tfms(ipcd->tfms);
383 ipcomp6_free_scratches();
384 }
386 static void ipcomp6_destroy(struct xfrm_state *x)
387 {
388 struct ipcomp_data *ipcd = x->data;
389 if (!ipcd)
390 return;
391 xfrm_state_delete_tunnel(x);
392 mutex_lock(&ipcomp6_resource_mutex);
393 ipcomp6_free_data(ipcd);
394 mutex_unlock(&ipcomp6_resource_mutex);
395 kfree(ipcd);
397 xfrm6_tunnel_free_spi((xfrm_address_t *)&x->props.saddr);
398 }
400 static int ipcomp6_init_state(struct xfrm_state *x)
401 {
402 int err;
403 struct ipcomp_data *ipcd;
404 struct xfrm_algo_desc *calg_desc;
406 err = -EINVAL;
407 if (!x->calg)
408 goto out;
410 if (x->encap)
411 goto out;
413 err = -ENOMEM;
414 ipcd = kzalloc(sizeof(*ipcd), GFP_KERNEL);
415 if (!ipcd)
416 goto out;
418 x->props.header_len = 0;
419 if (x->props.mode)
420 x->props.header_len += sizeof(struct ipv6hdr);
422 mutex_lock(&ipcomp6_resource_mutex);
423 if (!ipcomp6_alloc_scratches())
424 goto error;
426 ipcd->tfms = ipcomp6_alloc_tfms(x->calg->alg_name);
427 if (!ipcd->tfms)
428 goto error;
429 mutex_unlock(&ipcomp6_resource_mutex);
431 if (x->props.mode) {
432 err = ipcomp6_tunnel_attach(x);
433 if (err)
434 goto error_tunnel;
435 }
437 calg_desc = xfrm_calg_get_byname(x->calg->alg_name, 0);
438 BUG_ON(!calg_desc);
439 ipcd->threshold = calg_desc->uinfo.comp.threshold;
440 x->data = ipcd;
441 err = 0;
442 out:
443 return err;
444 error_tunnel:
445 mutex_lock(&ipcomp6_resource_mutex);
446 error:
447 ipcomp6_free_data(ipcd);
448 mutex_unlock(&ipcomp6_resource_mutex);
449 kfree(ipcd);
451 goto out;
452 }
454 static struct xfrm_type ipcomp6_type =
455 {
456 .description = "IPCOMP6",
457 .owner = THIS_MODULE,
458 .proto = IPPROTO_COMP,
459 .init_state = ipcomp6_init_state,
460 .destructor = ipcomp6_destroy,
461 .input = ipcomp6_input,
462 .output = ipcomp6_output,
463 };
465 static struct inet6_protocol ipcomp6_protocol =
466 {
467 .handler = xfrm6_rcv,
468 .err_handler = ipcomp6_err,
469 .flags = INET6_PROTO_NOPOLICY,
470 };
472 static int __init ipcomp6_init(void)
473 {
474 if (xfrm_register_type(&ipcomp6_type, AF_INET6) < 0) {
475 printk(KERN_INFO "ipcomp6 init: can't add xfrm type\n");
476 return -EAGAIN;
477 }
478 if (inet6_add_protocol(&ipcomp6_protocol, IPPROTO_COMP) < 0) {
479 printk(KERN_INFO "ipcomp6 init: can't add protocol\n");
480 xfrm_unregister_type(&ipcomp6_type, AF_INET6);
481 return -EAGAIN;
482 }
483 return 0;
484 }
486 static void __exit ipcomp6_fini(void)
487 {
488 if (inet6_del_protocol(&ipcomp6_protocol, IPPROTO_COMP) < 0)
489 printk(KERN_INFO "ipv6 ipcomp close: can't remove protocol\n");
490 if (xfrm_unregister_type(&ipcomp6_type, AF_INET6) < 0)
491 printk(KERN_INFO "ipv6 ipcomp close: can't remove xfrm type\n");
492 }
494 module_init(ipcomp6_init);
495 module_exit(ipcomp6_fini);
496 MODULE_LICENSE("GPL");
497 MODULE_DESCRIPTION("IP Payload Compression Protocol (IPComp) for IPv6 - RFC3173");
498 MODULE_AUTHOR("Mitsuru KANDA <mk@linux-ipv6.org>");