ia64/linux-2.6.18-xen.hg

view net/ipv6/ah6.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 * Copyright (C)2002 USAGI/WIDE Project
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17 *
18 * Authors
19 *
20 * Mitsuru KANDA @USAGI : IPv6 Support
21 * Kazunori MIYAZAWA @USAGI :
22 * Kunihiro Ishiguro <kunihiro@ipinfusion.com>
23 *
24 * This file is derived from net/ipv4/ah.c.
25 */
27 #include <linux/module.h>
28 #include <net/ip.h>
29 #include <net/ah.h>
30 #include <linux/crypto.h>
31 #include <linux/pfkeyv2.h>
32 #include <linux/string.h>
33 #include <net/icmp.h>
34 #include <net/ipv6.h>
35 #include <net/protocol.h>
36 #include <net/xfrm.h>
37 #include <asm/scatterlist.h>
39 static int zero_out_mutable_opts(struct ipv6_opt_hdr *opthdr)
40 {
41 u8 *opt = (u8 *)opthdr;
42 int len = ipv6_optlen(opthdr);
43 int off = 0;
44 int optlen = 0;
46 off += 2;
47 len -= 2;
49 while (len > 0) {
51 switch (opt[off]) {
53 case IPV6_TLV_PAD0:
54 optlen = 1;
55 break;
56 default:
57 if (len < 2)
58 goto bad;
59 optlen = opt[off+1]+2;
60 if (len < optlen)
61 goto bad;
62 if (opt[off] & 0x20)
63 memset(&opt[off+2], 0, opt[off+1]);
64 break;
65 }
67 off += optlen;
68 len -= optlen;
69 }
70 if (len == 0)
71 return 1;
73 bad:
74 return 0;
75 }
77 /**
78 * ipv6_rearrange_rthdr - rearrange IPv6 routing header
79 * @iph: IPv6 header
80 * @rthdr: routing header
81 *
82 * Rearrange the destination address in @iph and the addresses in @rthdr
83 * so that they appear in the order they will at the final destination.
84 * See Appendix A2 of RFC 2402 for details.
85 */
86 static void ipv6_rearrange_rthdr(struct ipv6hdr *iph, struct ipv6_rt_hdr *rthdr)
87 {
88 int segments, segments_left;
89 struct in6_addr *addrs;
90 struct in6_addr final_addr;
92 segments_left = rthdr->segments_left;
93 if (segments_left == 0)
94 return;
95 rthdr->segments_left = 0;
97 /* The value of rthdr->hdrlen has been verified either by the system
98 * call if it is locally generated, or by ipv6_rthdr_rcv() for incoming
99 * packets. So we can assume that it is even and that segments is
100 * greater than or equal to segments_left.
101 *
102 * For the same reason we can assume that this option is of type 0.
103 */
104 segments = rthdr->hdrlen >> 1;
106 addrs = ((struct rt0_hdr *)rthdr)->addr;
107 ipv6_addr_copy(&final_addr, addrs + segments - 1);
109 addrs += segments - segments_left;
110 memmove(addrs + 1, addrs, (segments_left - 1) * sizeof(*addrs));
112 ipv6_addr_copy(addrs, &iph->daddr);
113 ipv6_addr_copy(&iph->daddr, &final_addr);
114 }
116 static int ipv6_clear_mutable_options(struct ipv6hdr *iph, int len)
117 {
118 union {
119 struct ipv6hdr *iph;
120 struct ipv6_opt_hdr *opth;
121 struct ipv6_rt_hdr *rth;
122 char *raw;
123 } exthdr = { .iph = iph };
124 char *end = exthdr.raw + len;
125 int nexthdr = iph->nexthdr;
127 exthdr.iph++;
129 while (exthdr.raw < end) {
130 switch (nexthdr) {
131 case NEXTHDR_HOP:
132 case NEXTHDR_DEST:
133 if (!zero_out_mutable_opts(exthdr.opth)) {
134 LIMIT_NETDEBUG(
135 KERN_WARNING "overrun %sopts\n",
136 nexthdr == NEXTHDR_HOP ?
137 "hop" : "dest");
138 return -EINVAL;
139 }
140 break;
142 case NEXTHDR_ROUTING:
143 ipv6_rearrange_rthdr(iph, exthdr.rth);
144 break;
146 default :
147 return 0;
148 }
150 nexthdr = exthdr.opth->nexthdr;
151 exthdr.raw += ipv6_optlen(exthdr.opth);
152 }
154 return 0;
155 }
157 static int ah6_output(struct xfrm_state *x, struct sk_buff *skb)
158 {
159 int err;
160 int extlen;
161 struct ipv6hdr *top_iph;
162 struct ip_auth_hdr *ah;
163 struct ah_data *ahp;
164 u8 nexthdr;
165 char tmp_base[8];
166 struct {
167 struct in6_addr daddr;
168 char hdrs[0];
169 } *tmp_ext;
171 top_iph = (struct ipv6hdr *)skb->data;
172 top_iph->payload_len = htons(skb->len - sizeof(*top_iph));
174 nexthdr = *skb->nh.raw;
175 *skb->nh.raw = IPPROTO_AH;
177 /* When there are no extension headers, we only need to save the first
178 * 8 bytes of the base IP header.
179 */
180 memcpy(tmp_base, top_iph, sizeof(tmp_base));
182 tmp_ext = NULL;
183 extlen = skb->h.raw - (unsigned char *)(top_iph + 1);
184 if (extlen) {
185 extlen += sizeof(*tmp_ext);
186 tmp_ext = kmalloc(extlen, GFP_ATOMIC);
187 if (!tmp_ext) {
188 err = -ENOMEM;
189 goto error;
190 }
191 memcpy(tmp_ext, &top_iph->daddr, extlen);
192 err = ipv6_clear_mutable_options(top_iph,
193 extlen - sizeof(*tmp_ext) +
194 sizeof(*top_iph));
195 if (err)
196 goto error_free_iph;
197 }
199 ah = (struct ip_auth_hdr *)skb->h.raw;
200 ah->nexthdr = nexthdr;
202 top_iph->priority = 0;
203 top_iph->flow_lbl[0] = 0;
204 top_iph->flow_lbl[1] = 0;
205 top_iph->flow_lbl[2] = 0;
206 top_iph->hop_limit = 0;
208 ahp = x->data;
209 ah->hdrlen = (XFRM_ALIGN8(sizeof(struct ipv6_auth_hdr) +
210 ahp->icv_trunc_len) >> 2) - 2;
212 ah->reserved = 0;
213 ah->spi = x->id.spi;
214 ah->seq_no = htonl(++x->replay.oseq);
215 xfrm_aevent_doreplay(x);
216 ahp->icv(ahp, skb, ah->auth_data);
218 err = 0;
220 memcpy(top_iph, tmp_base, sizeof(tmp_base));
221 if (tmp_ext) {
222 memcpy(&top_iph->daddr, tmp_ext, extlen);
223 error_free_iph:
224 kfree(tmp_ext);
225 }
227 error:
228 return err;
229 }
231 static int ah6_input(struct xfrm_state *x, struct sk_buff *skb)
232 {
233 /*
234 * Before process AH
235 * [IPv6][Ext1][Ext2][AH][Dest][Payload]
236 * |<-------------->| hdr_len
237 *
238 * To erase AH:
239 * Keeping copy of cleared headers. After AH processing,
240 * Moving the pointer of skb->nh.raw by using skb_pull as long as AH
241 * header length. Then copy back the copy as long as hdr_len
242 * If destination header following AH exists, copy it into after [Ext2].
243 *
244 * |<>|[IPv6][Ext1][Ext2][Dest][Payload]
245 * There is offset of AH before IPv6 header after the process.
246 */
248 struct ipv6_auth_hdr *ah;
249 struct ah_data *ahp;
250 unsigned char *tmp_hdr = NULL;
251 u16 hdr_len;
252 u16 ah_hlen;
253 int nexthdr;
255 if (!pskb_may_pull(skb, sizeof(struct ip_auth_hdr)))
256 goto out;
258 /* We are going to _remove_ AH header to keep sockets happy,
259 * so... Later this can change. */
260 if (skb_cloned(skb) &&
261 pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
262 goto out;
264 hdr_len = skb->data - skb->nh.raw;
265 ah = (struct ipv6_auth_hdr*)skb->data;
266 ahp = x->data;
267 nexthdr = ah->nexthdr;
268 ah_hlen = (ah->hdrlen + 2) << 2;
270 if (ah_hlen != XFRM_ALIGN8(sizeof(struct ipv6_auth_hdr) + ahp->icv_full_len) &&
271 ah_hlen != XFRM_ALIGN8(sizeof(struct ipv6_auth_hdr) + ahp->icv_trunc_len))
272 goto out;
274 if (!pskb_may_pull(skb, ah_hlen))
275 goto out;
277 tmp_hdr = kmalloc(hdr_len, GFP_ATOMIC);
278 if (!tmp_hdr)
279 goto out;
280 memcpy(tmp_hdr, skb->nh.raw, hdr_len);
281 if (ipv6_clear_mutable_options(skb->nh.ipv6h, hdr_len))
282 goto free_out;
283 skb->nh.ipv6h->priority = 0;
284 skb->nh.ipv6h->flow_lbl[0] = 0;
285 skb->nh.ipv6h->flow_lbl[1] = 0;
286 skb->nh.ipv6h->flow_lbl[2] = 0;
287 skb->nh.ipv6h->hop_limit = 0;
289 {
290 u8 auth_data[MAX_AH_AUTH_LEN];
292 memcpy(auth_data, ah->auth_data, ahp->icv_trunc_len);
293 memset(ah->auth_data, 0, ahp->icv_trunc_len);
294 skb_push(skb, hdr_len);
295 ahp->icv(ahp, skb, ah->auth_data);
296 if (memcmp(ah->auth_data, auth_data, ahp->icv_trunc_len)) {
297 LIMIT_NETDEBUG(KERN_WARNING "ipsec ah authentication error\n");
298 x->stats.integrity_failed++;
299 goto free_out;
300 }
301 }
303 skb->h.raw = memcpy(skb->nh.raw += ah_hlen, tmp_hdr, hdr_len);
304 __skb_pull(skb, ah_hlen + hdr_len);
306 kfree(tmp_hdr);
308 return nexthdr;
310 free_out:
311 kfree(tmp_hdr);
312 out:
313 return -EINVAL;
314 }
316 static void ah6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
317 int type, int code, int offset, __u32 info)
318 {
319 struct ipv6hdr *iph = (struct ipv6hdr*)skb->data;
320 struct ip_auth_hdr *ah = (struct ip_auth_hdr*)(skb->data+offset);
321 struct xfrm_state *x;
323 if (type != ICMPV6_DEST_UNREACH &&
324 type != ICMPV6_PKT_TOOBIG)
325 return;
327 x = xfrm_state_lookup((xfrm_address_t *)&iph->daddr, ah->spi, IPPROTO_AH, AF_INET6);
328 if (!x)
329 return;
331 NETDEBUG(KERN_DEBUG "pmtu discovery on SA AH/%08x/" NIP6_FMT "\n",
332 ntohl(ah->spi), NIP6(iph->daddr));
334 xfrm_state_put(x);
335 }
337 static int ah6_init_state(struct xfrm_state *x)
338 {
339 struct ah_data *ahp = NULL;
340 struct xfrm_algo_desc *aalg_desc;
342 if (!x->aalg)
343 goto error;
345 /* null auth can use a zero length key */
346 if (x->aalg->alg_key_len > 512)
347 goto error;
349 if (x->encap)
350 goto error;
352 ahp = kzalloc(sizeof(*ahp), GFP_KERNEL);
353 if (ahp == NULL)
354 return -ENOMEM;
356 ahp->key = x->aalg->alg_key;
357 ahp->key_len = (x->aalg->alg_key_len+7)/8;
358 ahp->tfm = crypto_alloc_tfm(x->aalg->alg_name, 0);
359 if (!ahp->tfm)
360 goto error;
361 ahp->icv = ah_hmac_digest;
363 /*
364 * Lookup the algorithm description maintained by xfrm_algo,
365 * verify crypto transform properties, and store information
366 * we need for AH processing. This lookup cannot fail here
367 * after a successful crypto_alloc_tfm().
368 */
369 aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0);
370 BUG_ON(!aalg_desc);
372 if (aalg_desc->uinfo.auth.icv_fullbits/8 !=
373 crypto_tfm_alg_digestsize(ahp->tfm)) {
374 printk(KERN_INFO "AH: %s digestsize %u != %hu\n",
375 x->aalg->alg_name, crypto_tfm_alg_digestsize(ahp->tfm),
376 aalg_desc->uinfo.auth.icv_fullbits/8);
377 goto error;
378 }
380 ahp->icv_full_len = aalg_desc->uinfo.auth.icv_fullbits/8;
381 ahp->icv_trunc_len = aalg_desc->uinfo.auth.icv_truncbits/8;
383 BUG_ON(ahp->icv_trunc_len > MAX_AH_AUTH_LEN);
385 ahp->work_icv = kmalloc(ahp->icv_full_len, GFP_KERNEL);
386 if (!ahp->work_icv)
387 goto error;
389 x->props.header_len = XFRM_ALIGN8(sizeof(struct ipv6_auth_hdr) + ahp->icv_trunc_len);
390 if (x->props.mode)
391 x->props.header_len += sizeof(struct ipv6hdr);
392 x->data = ahp;
394 return 0;
396 error:
397 if (ahp) {
398 kfree(ahp->work_icv);
399 crypto_free_tfm(ahp->tfm);
400 kfree(ahp);
401 }
402 return -EINVAL;
403 }
405 static void ah6_destroy(struct xfrm_state *x)
406 {
407 struct ah_data *ahp = x->data;
409 if (!ahp)
410 return;
412 kfree(ahp->work_icv);
413 ahp->work_icv = NULL;
414 crypto_free_tfm(ahp->tfm);
415 ahp->tfm = NULL;
416 kfree(ahp);
417 }
419 static struct xfrm_type ah6_type =
420 {
421 .description = "AH6",
422 .owner = THIS_MODULE,
423 .proto = IPPROTO_AH,
424 .init_state = ah6_init_state,
425 .destructor = ah6_destroy,
426 .input = ah6_input,
427 .output = ah6_output
428 };
430 static struct inet6_protocol ah6_protocol = {
431 .handler = xfrm6_rcv,
432 .err_handler = ah6_err,
433 .flags = INET6_PROTO_NOPOLICY,
434 };
436 static int __init ah6_init(void)
437 {
438 if (xfrm_register_type(&ah6_type, AF_INET6) < 0) {
439 printk(KERN_INFO "ipv6 ah init: can't add xfrm type\n");
440 return -EAGAIN;
441 }
443 if (inet6_add_protocol(&ah6_protocol, IPPROTO_AH) < 0) {
444 printk(KERN_INFO "ipv6 ah init: can't add protocol\n");
445 xfrm_unregister_type(&ah6_type, AF_INET6);
446 return -EAGAIN;
447 }
449 return 0;
450 }
452 static void __exit ah6_fini(void)
453 {
454 if (inet6_del_protocol(&ah6_protocol, IPPROTO_AH) < 0)
455 printk(KERN_INFO "ipv6 ah close: can't remove protocol\n");
457 if (xfrm_unregister_type(&ah6_type, AF_INET6) < 0)
458 printk(KERN_INFO "ipv6 ah close: can't remove xfrm type\n");
460 }
462 module_init(ah6_init);
463 module_exit(ah6_fini);
465 MODULE_LICENSE("GPL");