ia64/linux-2.6.18-xen.hg

view net/ipv6/anycast.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 * Anycast support for IPv6
3 * Linux INET6 implementation
4 *
5 * Authors:
6 * David L Stevens (dlstevens@us.ibm.com)
7 *
8 * based heavily on net/ipv6/mcast.c
9 *
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License
12 * as published by the Free Software Foundation; either version
13 * 2 of the License, or (at your option) any later version.
14 */
16 #include <linux/capability.h>
17 #include <linux/module.h>
18 #include <linux/errno.h>
19 #include <linux/types.h>
20 #include <linux/random.h>
21 #include <linux/string.h>
22 #include <linux/socket.h>
23 #include <linux/sockios.h>
24 #include <linux/sched.h>
25 #include <linux/net.h>
26 #include <linux/in6.h>
27 #include <linux/netdevice.h>
28 #include <linux/if_arp.h>
29 #include <linux/route.h>
30 #include <linux/init.h>
31 #include <linux/proc_fs.h>
32 #include <linux/seq_file.h>
34 #include <net/sock.h>
35 #include <net/snmp.h>
37 #include <net/ipv6.h>
38 #include <net/protocol.h>
39 #include <net/if_inet6.h>
40 #include <net/ndisc.h>
41 #include <net/addrconf.h>
42 #include <net/ip6_route.h>
44 #include <net/checksum.h>
46 static int ipv6_dev_ac_dec(struct net_device *dev, struct in6_addr *addr);
48 /* Big ac list lock for all the sockets */
49 static DEFINE_RWLOCK(ipv6_sk_ac_lock);
51 static int
52 ip6_onlink(struct in6_addr *addr, struct net_device *dev)
53 {
54 struct inet6_dev *idev;
55 struct inet6_ifaddr *ifa;
56 int onlink;
58 onlink = 0;
59 read_lock(&addrconf_lock);
60 idev = __in6_dev_get(dev);
61 if (idev) {
62 read_lock_bh(&idev->lock);
63 for (ifa=idev->addr_list; ifa; ifa=ifa->if_next) {
64 onlink = ipv6_prefix_equal(addr, &ifa->addr,
65 ifa->prefix_len);
66 if (onlink)
67 break;
68 }
69 read_unlock_bh(&idev->lock);
70 }
71 read_unlock(&addrconf_lock);
72 return onlink;
73 }
75 /*
76 * socket join an anycast group
77 */
79 int ipv6_sock_ac_join(struct sock *sk, int ifindex, struct in6_addr *addr)
80 {
81 struct ipv6_pinfo *np = inet6_sk(sk);
82 struct net_device *dev = NULL;
83 struct inet6_dev *idev;
84 struct ipv6_ac_socklist *pac;
85 int ishost = !ipv6_devconf.forwarding;
86 int err = 0;
88 if (!capable(CAP_NET_ADMIN))
89 return -EPERM;
90 if (ipv6_addr_is_multicast(addr))
91 return -EINVAL;
92 if (ipv6_chk_addr(addr, NULL, 0))
93 return -EINVAL;
95 pac = sock_kmalloc(sk, sizeof(struct ipv6_ac_socklist), GFP_KERNEL);
96 if (pac == NULL)
97 return -ENOMEM;
98 pac->acl_next = NULL;
99 ipv6_addr_copy(&pac->acl_addr, addr);
101 if (ifindex == 0) {
102 struct rt6_info *rt;
104 rt = rt6_lookup(addr, NULL, 0, 0);
105 if (rt) {
106 dev = rt->rt6i_dev;
107 dev_hold(dev);
108 dst_release(&rt->u.dst);
109 } else if (ishost) {
110 err = -EADDRNOTAVAIL;
111 goto out_free_pac;
112 } else {
113 /* router, no matching interface: just pick one */
115 dev = dev_get_by_flags(IFF_UP, IFF_UP|IFF_LOOPBACK);
116 }
117 } else
118 dev = dev_get_by_index(ifindex);
120 if (dev == NULL) {
121 err = -ENODEV;
122 goto out_free_pac;
123 }
125 idev = in6_dev_get(dev);
126 if (!idev) {
127 if (ifindex)
128 err = -ENODEV;
129 else
130 err = -EADDRNOTAVAIL;
131 goto out_dev_put;
132 }
133 /* reset ishost, now that we have a specific device */
134 ishost = !idev->cnf.forwarding;
135 in6_dev_put(idev);
137 pac->acl_ifindex = dev->ifindex;
139 /* XXX
140 * For hosts, allow link-local or matching prefix anycasts.
141 * This obviates the need for propagating anycast routes while
142 * still allowing some non-router anycast participation.
143 */
144 if (!ip6_onlink(addr, dev)) {
145 if (ishost)
146 err = -EADDRNOTAVAIL;
147 if (err)
148 goto out_dev_put;
149 }
151 err = ipv6_dev_ac_inc(dev, addr);
152 if (err)
153 goto out_dev_put;
155 write_lock_bh(&ipv6_sk_ac_lock);
156 pac->acl_next = np->ipv6_ac_list;
157 np->ipv6_ac_list = pac;
158 write_unlock_bh(&ipv6_sk_ac_lock);
160 dev_put(dev);
162 return 0;
164 out_dev_put:
165 dev_put(dev);
166 out_free_pac:
167 sock_kfree_s(sk, pac, sizeof(*pac));
168 return err;
169 }
171 /*
172 * socket leave an anycast group
173 */
174 int ipv6_sock_ac_drop(struct sock *sk, int ifindex, struct in6_addr *addr)
175 {
176 struct ipv6_pinfo *np = inet6_sk(sk);
177 struct net_device *dev;
178 struct ipv6_ac_socklist *pac, *prev_pac;
180 write_lock_bh(&ipv6_sk_ac_lock);
181 prev_pac = NULL;
182 for (pac = np->ipv6_ac_list; pac; pac = pac->acl_next) {
183 if ((ifindex == 0 || pac->acl_ifindex == ifindex) &&
184 ipv6_addr_equal(&pac->acl_addr, addr))
185 break;
186 prev_pac = pac;
187 }
188 if (!pac) {
189 write_unlock_bh(&ipv6_sk_ac_lock);
190 return -ENOENT;
191 }
192 if (prev_pac)
193 prev_pac->acl_next = pac->acl_next;
194 else
195 np->ipv6_ac_list = pac->acl_next;
197 write_unlock_bh(&ipv6_sk_ac_lock);
199 dev = dev_get_by_index(pac->acl_ifindex);
200 if (dev) {
201 ipv6_dev_ac_dec(dev, &pac->acl_addr);
202 dev_put(dev);
203 }
204 sock_kfree_s(sk, pac, sizeof(*pac));
205 return 0;
206 }
208 void ipv6_sock_ac_close(struct sock *sk)
209 {
210 struct ipv6_pinfo *np = inet6_sk(sk);
211 struct net_device *dev = NULL;
212 struct ipv6_ac_socklist *pac;
213 int prev_index;
215 write_lock_bh(&ipv6_sk_ac_lock);
216 pac = np->ipv6_ac_list;
217 np->ipv6_ac_list = NULL;
218 write_unlock_bh(&ipv6_sk_ac_lock);
220 prev_index = 0;
221 while (pac) {
222 struct ipv6_ac_socklist *next = pac->acl_next;
224 if (pac->acl_ifindex != prev_index) {
225 if (dev)
226 dev_put(dev);
227 dev = dev_get_by_index(pac->acl_ifindex);
228 prev_index = pac->acl_ifindex;
229 }
230 if (dev)
231 ipv6_dev_ac_dec(dev, &pac->acl_addr);
232 sock_kfree_s(sk, pac, sizeof(*pac));
233 pac = next;
234 }
235 if (dev)
236 dev_put(dev);
237 }
239 #if 0
240 /* The function is not used, which is funny. Apparently, author
241 * supposed to use it to filter out datagrams inside udp/raw but forgot.
242 *
243 * It is OK, anycasts are not special comparing to delivery to unicasts.
244 */
246 int inet6_ac_check(struct sock *sk, struct in6_addr *addr, int ifindex)
247 {
248 struct ipv6_ac_socklist *pac;
249 struct ipv6_pinfo *np = inet6_sk(sk);
250 int found;
252 found = 0;
253 read_lock(&ipv6_sk_ac_lock);
254 for (pac=np->ipv6_ac_list; pac; pac=pac->acl_next) {
255 if (ifindex && pac->acl_ifindex != ifindex)
256 continue;
257 found = ipv6_addr_equal(&pac->acl_addr, addr);
258 if (found)
259 break;
260 }
261 read_unlock(&ipv6_sk_ac_lock);
263 return found;
264 }
266 #endif
268 static void aca_put(struct ifacaddr6 *ac)
269 {
270 if (atomic_dec_and_test(&ac->aca_refcnt)) {
271 in6_dev_put(ac->aca_idev);
272 dst_release(&ac->aca_rt->u.dst);
273 kfree(ac);
274 }
275 }
277 /*
278 * device anycast group inc (add if not found)
279 */
280 int ipv6_dev_ac_inc(struct net_device *dev, struct in6_addr *addr)
281 {
282 struct ifacaddr6 *aca;
283 struct inet6_dev *idev;
284 struct rt6_info *rt;
285 int err;
287 idev = in6_dev_get(dev);
289 if (idev == NULL)
290 return -EINVAL;
292 write_lock_bh(&idev->lock);
293 if (idev->dead) {
294 err = -ENODEV;
295 goto out;
296 }
298 for (aca = idev->ac_list; aca; aca = aca->aca_next) {
299 if (ipv6_addr_equal(&aca->aca_addr, addr)) {
300 aca->aca_users++;
301 err = 0;
302 goto out;
303 }
304 }
306 /*
307 * not found: create a new one.
308 */
310 aca = kzalloc(sizeof(struct ifacaddr6), GFP_ATOMIC);
312 if (aca == NULL) {
313 err = -ENOMEM;
314 goto out;
315 }
317 rt = addrconf_dst_alloc(idev, addr, 1);
318 if (IS_ERR(rt)) {
319 kfree(aca);
320 err = PTR_ERR(rt);
321 goto out;
322 }
324 ipv6_addr_copy(&aca->aca_addr, addr);
325 aca->aca_idev = idev;
326 aca->aca_rt = rt;
327 aca->aca_users = 1;
328 /* aca_tstamp should be updated upon changes */
329 aca->aca_cstamp = aca->aca_tstamp = jiffies;
330 atomic_set(&aca->aca_refcnt, 2);
331 spin_lock_init(&aca->aca_lock);
333 aca->aca_next = idev->ac_list;
334 idev->ac_list = aca;
335 write_unlock_bh(&idev->lock);
337 dst_hold(&rt->u.dst);
338 if (ip6_ins_rt(rt, NULL, NULL, NULL))
339 dst_release(&rt->u.dst);
341 addrconf_join_solict(dev, &aca->aca_addr);
343 aca_put(aca);
344 return 0;
345 out:
346 write_unlock_bh(&idev->lock);
347 in6_dev_put(idev);
348 return err;
349 }
351 /*
352 * device anycast group decrement
353 */
354 int __ipv6_dev_ac_dec(struct inet6_dev *idev, struct in6_addr *addr)
355 {
356 struct ifacaddr6 *aca, *prev_aca;
358 write_lock_bh(&idev->lock);
359 prev_aca = NULL;
360 for (aca = idev->ac_list; aca; aca = aca->aca_next) {
361 if (ipv6_addr_equal(&aca->aca_addr, addr))
362 break;
363 prev_aca = aca;
364 }
365 if (!aca) {
366 write_unlock_bh(&idev->lock);
367 return -ENOENT;
368 }
369 if (--aca->aca_users > 0) {
370 write_unlock_bh(&idev->lock);
371 return 0;
372 }
373 if (prev_aca)
374 prev_aca->aca_next = aca->aca_next;
375 else
376 idev->ac_list = aca->aca_next;
377 write_unlock_bh(&idev->lock);
378 addrconf_leave_solict(idev, &aca->aca_addr);
380 dst_hold(&aca->aca_rt->u.dst);
381 if (ip6_del_rt(aca->aca_rt, NULL, NULL, NULL))
382 dst_free(&aca->aca_rt->u.dst);
383 else
384 dst_release(&aca->aca_rt->u.dst);
386 aca_put(aca);
387 return 0;
388 }
390 static int ipv6_dev_ac_dec(struct net_device *dev, struct in6_addr *addr)
391 {
392 int ret;
393 struct inet6_dev *idev = in6_dev_get(dev);
394 if (idev == NULL)
395 return -ENODEV;
396 ret = __ipv6_dev_ac_dec(idev, addr);
397 in6_dev_put(idev);
398 return ret;
399 }
401 /*
402 * check if the interface has this anycast address
403 */
404 static int ipv6_chk_acast_dev(struct net_device *dev, struct in6_addr *addr)
405 {
406 struct inet6_dev *idev;
407 struct ifacaddr6 *aca;
409 idev = in6_dev_get(dev);
410 if (idev) {
411 read_lock_bh(&idev->lock);
412 for (aca = idev->ac_list; aca; aca = aca->aca_next)
413 if (ipv6_addr_equal(&aca->aca_addr, addr))
414 break;
415 read_unlock_bh(&idev->lock);
416 in6_dev_put(idev);
417 return aca != 0;
418 }
419 return 0;
420 }
422 /*
423 * check if given interface (or any, if dev==0) has this anycast address
424 */
425 int ipv6_chk_acast_addr(struct net_device *dev, struct in6_addr *addr)
426 {
427 if (dev)
428 return ipv6_chk_acast_dev(dev, addr);
429 read_lock(&dev_base_lock);
430 for (dev=dev_base; dev; dev=dev->next)
431 if (ipv6_chk_acast_dev(dev, addr))
432 break;
433 read_unlock(&dev_base_lock);
434 return dev != 0;
435 }
438 #ifdef CONFIG_PROC_FS
439 struct ac6_iter_state {
440 struct net_device *dev;
441 struct inet6_dev *idev;
442 };
444 #define ac6_seq_private(seq) ((struct ac6_iter_state *)(seq)->private)
446 static inline struct ifacaddr6 *ac6_get_first(struct seq_file *seq)
447 {
448 struct ifacaddr6 *im = NULL;
449 struct ac6_iter_state *state = ac6_seq_private(seq);
451 for (state->dev = dev_base, state->idev = NULL;
452 state->dev;
453 state->dev = state->dev->next) {
454 struct inet6_dev *idev;
455 idev = in6_dev_get(state->dev);
456 if (!idev)
457 continue;
458 read_lock_bh(&idev->lock);
459 im = idev->ac_list;
460 if (im) {
461 state->idev = idev;
462 break;
463 }
464 read_unlock_bh(&idev->lock);
465 }
466 return im;
467 }
469 static struct ifacaddr6 *ac6_get_next(struct seq_file *seq, struct ifacaddr6 *im)
470 {
471 struct ac6_iter_state *state = ac6_seq_private(seq);
473 im = im->aca_next;
474 while (!im) {
475 if (likely(state->idev != NULL)) {
476 read_unlock_bh(&state->idev->lock);
477 in6_dev_put(state->idev);
478 }
479 state->dev = state->dev->next;
480 if (!state->dev) {
481 state->idev = NULL;
482 break;
483 }
484 state->idev = in6_dev_get(state->dev);
485 if (!state->idev)
486 continue;
487 read_lock_bh(&state->idev->lock);
488 im = state->idev->ac_list;
489 }
490 return im;
491 }
493 static struct ifacaddr6 *ac6_get_idx(struct seq_file *seq, loff_t pos)
494 {
495 struct ifacaddr6 *im = ac6_get_first(seq);
496 if (im)
497 while (pos && (im = ac6_get_next(seq, im)) != NULL)
498 --pos;
499 return pos ? NULL : im;
500 }
502 static void *ac6_seq_start(struct seq_file *seq, loff_t *pos)
503 {
504 read_lock(&dev_base_lock);
505 return ac6_get_idx(seq, *pos);
506 }
508 static void *ac6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
509 {
510 struct ifacaddr6 *im;
511 im = ac6_get_next(seq, v);
512 ++*pos;
513 return im;
514 }
516 static void ac6_seq_stop(struct seq_file *seq, void *v)
517 {
518 struct ac6_iter_state *state = ac6_seq_private(seq);
519 if (likely(state->idev != NULL)) {
520 read_unlock_bh(&state->idev->lock);
521 in6_dev_put(state->idev);
522 }
523 read_unlock(&dev_base_lock);
524 }
526 static int ac6_seq_show(struct seq_file *seq, void *v)
527 {
528 struct ifacaddr6 *im = (struct ifacaddr6 *)v;
529 struct ac6_iter_state *state = ac6_seq_private(seq);
531 seq_printf(seq,
532 "%-4d %-15s " NIP6_SEQFMT " %5d\n",
533 state->dev->ifindex, state->dev->name,
534 NIP6(im->aca_addr),
535 im->aca_users);
536 return 0;
537 }
539 static struct seq_operations ac6_seq_ops = {
540 .start = ac6_seq_start,
541 .next = ac6_seq_next,
542 .stop = ac6_seq_stop,
543 .show = ac6_seq_show,
544 };
546 static int ac6_seq_open(struct inode *inode, struct file *file)
547 {
548 struct seq_file *seq;
549 int rc = -ENOMEM;
550 struct ac6_iter_state *s = kzalloc(sizeof(*s), GFP_KERNEL);
552 if (!s)
553 goto out;
555 rc = seq_open(file, &ac6_seq_ops);
556 if (rc)
557 goto out_kfree;
559 seq = file->private_data;
560 seq->private = s;
561 out:
562 return rc;
563 out_kfree:
564 kfree(s);
565 goto out;
566 }
568 static struct file_operations ac6_seq_fops = {
569 .owner = THIS_MODULE,
570 .open = ac6_seq_open,
571 .read = seq_read,
572 .llseek = seq_lseek,
573 .release = seq_release_private,
574 };
576 int __init ac6_proc_init(void)
577 {
578 if (!proc_net_fops_create("anycast6", S_IRUGO, &ac6_seq_fops))
579 return -ENOMEM;
581 return 0;
582 }
584 void ac6_proc_exit(void)
585 {
586 proc_net_remove("anycast6");
587 }
588 #endif