Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Anycast support for IPv6 |
YOSHIFUJI Hideaki | 1ab1457 | 2007-02-09 23:24:49 +0900 | [diff] [blame] | 3 | * Linux INET6 implementation |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | */ |
| 15 | |
Randy Dunlap | 4fc268d | 2006-01-11 12:17:47 -0800 | [diff] [blame] | 16 | #include <linux/capability.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 24 | #include <linux/net.h> |
| 25 | #include <linux/in6.h> |
| 26 | #include <linux/netdevice.h> |
| 27 | #include <linux/if_arp.h> |
| 28 | #include <linux/route.h> |
| 29 | #include <linux/init.h> |
| 30 | #include <linux/proc_fs.h> |
| 31 | #include <linux/seq_file.h> |
| 32 | |
| 33 | #include <net/sock.h> |
| 34 | #include <net/snmp.h> |
| 35 | |
| 36 | #include <net/ipv6.h> |
| 37 | #include <net/protocol.h> |
| 38 | #include <net/if_inet6.h> |
| 39 | #include <net/ndisc.h> |
| 40 | #include <net/addrconf.h> |
| 41 | #include <net/ip6_route.h> |
| 42 | |
| 43 | #include <net/checksum.h> |
| 44 | |
| 45 | static int ipv6_dev_ac_dec(struct net_device *dev, struct in6_addr *addr); |
| 46 | |
| 47 | /* Big ac list lock for all the sockets */ |
| 48 | static DEFINE_RWLOCK(ipv6_sk_ac_lock); |
| 49 | |
| 50 | static int |
| 51 | ip6_onlink(struct in6_addr *addr, struct net_device *dev) |
| 52 | { |
| 53 | struct inet6_dev *idev; |
| 54 | struct inet6_ifaddr *ifa; |
| 55 | int onlink; |
| 56 | |
| 57 | onlink = 0; |
YOSHIFUJI Hideaki | 8814c4b | 2006-09-22 14:44:24 -0700 | [diff] [blame] | 58 | rcu_read_lock(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 59 | idev = __in6_dev_get(dev); |
| 60 | if (idev) { |
| 61 | read_lock_bh(&idev->lock); |
| 62 | for (ifa=idev->addr_list; ifa; ifa=ifa->if_next) { |
| 63 | onlink = ipv6_prefix_equal(addr, &ifa->addr, |
| 64 | ifa->prefix_len); |
| 65 | if (onlink) |
| 66 | break; |
| 67 | } |
| 68 | read_unlock_bh(&idev->lock); |
| 69 | } |
YOSHIFUJI Hideaki | 8814c4b | 2006-09-22 14:44:24 -0700 | [diff] [blame] | 70 | rcu_read_unlock(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 71 | return onlink; |
| 72 | } |
| 73 | |
| 74 | /* |
| 75 | * socket join an anycast group |
| 76 | */ |
| 77 | |
| 78 | int ipv6_sock_ac_join(struct sock *sk, int ifindex, struct in6_addr *addr) |
| 79 | { |
| 80 | struct ipv6_pinfo *np = inet6_sk(sk); |
| 81 | struct net_device *dev = NULL; |
| 82 | struct inet6_dev *idev; |
| 83 | struct ipv6_ac_socklist *pac; |
| 84 | int ishost = !ipv6_devconf.forwarding; |
| 85 | int err = 0; |
| 86 | |
| 87 | if (!capable(CAP_NET_ADMIN)) |
| 88 | return -EPERM; |
| 89 | if (ipv6_addr_is_multicast(addr)) |
| 90 | return -EINVAL; |
| 91 | if (ipv6_chk_addr(addr, NULL, 0)) |
| 92 | return -EINVAL; |
| 93 | |
| 94 | pac = sock_kmalloc(sk, sizeof(struct ipv6_ac_socklist), GFP_KERNEL); |
| 95 | if (pac == NULL) |
| 96 | return -ENOMEM; |
| 97 | pac->acl_next = NULL; |
| 98 | ipv6_addr_copy(&pac->acl_addr, addr); |
| 99 | |
| 100 | if (ifindex == 0) { |
| 101 | struct rt6_info *rt; |
| 102 | |
| 103 | rt = rt6_lookup(addr, NULL, 0, 0); |
| 104 | if (rt) { |
| 105 | dev = rt->rt6i_dev; |
| 106 | dev_hold(dev); |
| 107 | dst_release(&rt->u.dst); |
| 108 | } else if (ishost) { |
| 109 | err = -EADDRNOTAVAIL; |
| 110 | goto out_free_pac; |
| 111 | } else { |
| 112 | /* router, no matching interface: just pick one */ |
| 113 | |
| 114 | dev = dev_get_by_flags(IFF_UP, IFF_UP|IFF_LOOPBACK); |
| 115 | } |
| 116 | } else |
| 117 | dev = dev_get_by_index(ifindex); |
| 118 | |
| 119 | if (dev == NULL) { |
| 120 | err = -ENODEV; |
| 121 | goto out_free_pac; |
| 122 | } |
| 123 | |
| 124 | idev = in6_dev_get(dev); |
| 125 | if (!idev) { |
| 126 | if (ifindex) |
| 127 | err = -ENODEV; |
| 128 | else |
| 129 | err = -EADDRNOTAVAIL; |
| 130 | goto out_dev_put; |
| 131 | } |
| 132 | /* reset ishost, now that we have a specific device */ |
| 133 | ishost = !idev->cnf.forwarding; |
| 134 | in6_dev_put(idev); |
| 135 | |
| 136 | pac->acl_ifindex = dev->ifindex; |
| 137 | |
| 138 | /* XXX |
| 139 | * For hosts, allow link-local or matching prefix anycasts. |
| 140 | * This obviates the need for propagating anycast routes while |
| 141 | * still allowing some non-router anycast participation. |
| 142 | */ |
| 143 | if (!ip6_onlink(addr, dev)) { |
| 144 | if (ishost) |
| 145 | err = -EADDRNOTAVAIL; |
| 146 | if (err) |
| 147 | goto out_dev_put; |
| 148 | } |
| 149 | |
| 150 | err = ipv6_dev_ac_inc(dev, addr); |
| 151 | if (err) |
| 152 | goto out_dev_put; |
| 153 | |
| 154 | write_lock_bh(&ipv6_sk_ac_lock); |
| 155 | pac->acl_next = np->ipv6_ac_list; |
| 156 | np->ipv6_ac_list = pac; |
| 157 | write_unlock_bh(&ipv6_sk_ac_lock); |
| 158 | |
| 159 | dev_put(dev); |
| 160 | |
| 161 | return 0; |
| 162 | |
| 163 | out_dev_put: |
| 164 | dev_put(dev); |
| 165 | out_free_pac: |
| 166 | sock_kfree_s(sk, pac, sizeof(*pac)); |
| 167 | return err; |
| 168 | } |
| 169 | |
| 170 | /* |
| 171 | * socket leave an anycast group |
| 172 | */ |
| 173 | int ipv6_sock_ac_drop(struct sock *sk, int ifindex, struct in6_addr *addr) |
| 174 | { |
| 175 | struct ipv6_pinfo *np = inet6_sk(sk); |
| 176 | struct net_device *dev; |
| 177 | struct ipv6_ac_socklist *pac, *prev_pac; |
| 178 | |
| 179 | write_lock_bh(&ipv6_sk_ac_lock); |
| 180 | prev_pac = NULL; |
| 181 | for (pac = np->ipv6_ac_list; pac; pac = pac->acl_next) { |
| 182 | if ((ifindex == 0 || pac->acl_ifindex == ifindex) && |
| 183 | ipv6_addr_equal(&pac->acl_addr, addr)) |
| 184 | break; |
| 185 | prev_pac = pac; |
| 186 | } |
| 187 | if (!pac) { |
| 188 | write_unlock_bh(&ipv6_sk_ac_lock); |
| 189 | return -ENOENT; |
| 190 | } |
| 191 | if (prev_pac) |
| 192 | prev_pac->acl_next = pac->acl_next; |
| 193 | else |
| 194 | np->ipv6_ac_list = pac->acl_next; |
| 195 | |
| 196 | write_unlock_bh(&ipv6_sk_ac_lock); |
| 197 | |
| 198 | dev = dev_get_by_index(pac->acl_ifindex); |
| 199 | if (dev) { |
| 200 | ipv6_dev_ac_dec(dev, &pac->acl_addr); |
| 201 | dev_put(dev); |
| 202 | } |
| 203 | sock_kfree_s(sk, pac, sizeof(*pac)); |
| 204 | return 0; |
| 205 | } |
| 206 | |
| 207 | void ipv6_sock_ac_close(struct sock *sk) |
| 208 | { |
| 209 | struct ipv6_pinfo *np = inet6_sk(sk); |
| 210 | struct net_device *dev = NULL; |
| 211 | struct ipv6_ac_socklist *pac; |
| 212 | int prev_index; |
| 213 | |
| 214 | write_lock_bh(&ipv6_sk_ac_lock); |
| 215 | pac = np->ipv6_ac_list; |
| 216 | np->ipv6_ac_list = NULL; |
| 217 | write_unlock_bh(&ipv6_sk_ac_lock); |
| 218 | |
| 219 | prev_index = 0; |
| 220 | while (pac) { |
| 221 | struct ipv6_ac_socklist *next = pac->acl_next; |
| 222 | |
| 223 | if (pac->acl_ifindex != prev_index) { |
| 224 | if (dev) |
| 225 | dev_put(dev); |
| 226 | dev = dev_get_by_index(pac->acl_ifindex); |
| 227 | prev_index = pac->acl_ifindex; |
| 228 | } |
| 229 | if (dev) |
| 230 | ipv6_dev_ac_dec(dev, &pac->acl_addr); |
| 231 | sock_kfree_s(sk, pac, sizeof(*pac)); |
| 232 | pac = next; |
| 233 | } |
| 234 | if (dev) |
| 235 | dev_put(dev); |
| 236 | } |
| 237 | |
| 238 | #if 0 |
| 239 | /* The function is not used, which is funny. Apparently, author |
| 240 | * supposed to use it to filter out datagrams inside udp/raw but forgot. |
| 241 | * |
| 242 | * It is OK, anycasts are not special comparing to delivery to unicasts. |
| 243 | */ |
| 244 | |
| 245 | int inet6_ac_check(struct sock *sk, struct in6_addr *addr, int ifindex) |
| 246 | { |
| 247 | struct ipv6_ac_socklist *pac; |
| 248 | struct ipv6_pinfo *np = inet6_sk(sk); |
| 249 | int found; |
| 250 | |
| 251 | found = 0; |
| 252 | read_lock(&ipv6_sk_ac_lock); |
| 253 | for (pac=np->ipv6_ac_list; pac; pac=pac->acl_next) { |
| 254 | if (ifindex && pac->acl_ifindex != ifindex) |
| 255 | continue; |
| 256 | found = ipv6_addr_equal(&pac->acl_addr, addr); |
| 257 | if (found) |
| 258 | break; |
| 259 | } |
| 260 | read_unlock(&ipv6_sk_ac_lock); |
| 261 | |
| 262 | return found; |
| 263 | } |
| 264 | |
| 265 | #endif |
| 266 | |
| 267 | static void aca_put(struct ifacaddr6 *ac) |
| 268 | { |
| 269 | if (atomic_dec_and_test(&ac->aca_refcnt)) { |
| 270 | in6_dev_put(ac->aca_idev); |
| 271 | dst_release(&ac->aca_rt->u.dst); |
| 272 | kfree(ac); |
| 273 | } |
| 274 | } |
| 275 | |
| 276 | /* |
| 277 | * device anycast group inc (add if not found) |
| 278 | */ |
| 279 | int ipv6_dev_ac_inc(struct net_device *dev, struct in6_addr *addr) |
| 280 | { |
| 281 | struct ifacaddr6 *aca; |
| 282 | struct inet6_dev *idev; |
| 283 | struct rt6_info *rt; |
| 284 | int err; |
| 285 | |
| 286 | idev = in6_dev_get(dev); |
| 287 | |
| 288 | if (idev == NULL) |
| 289 | return -EINVAL; |
| 290 | |
| 291 | write_lock_bh(&idev->lock); |
| 292 | if (idev->dead) { |
| 293 | err = -ENODEV; |
| 294 | goto out; |
| 295 | } |
| 296 | |
| 297 | for (aca = idev->ac_list; aca; aca = aca->aca_next) { |
| 298 | if (ipv6_addr_equal(&aca->aca_addr, addr)) { |
| 299 | aca->aca_users++; |
| 300 | err = 0; |
| 301 | goto out; |
| 302 | } |
| 303 | } |
| 304 | |
| 305 | /* |
| 306 | * not found: create a new one. |
| 307 | */ |
| 308 | |
Ingo Oeser | 0c600ed | 2006-03-20 23:01:32 -0800 | [diff] [blame] | 309 | aca = kzalloc(sizeof(struct ifacaddr6), GFP_ATOMIC); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 310 | |
| 311 | if (aca == NULL) { |
| 312 | err = -ENOMEM; |
| 313 | goto out; |
| 314 | } |
| 315 | |
| 316 | rt = addrconf_dst_alloc(idev, addr, 1); |
| 317 | if (IS_ERR(rt)) { |
| 318 | kfree(aca); |
| 319 | err = PTR_ERR(rt); |
| 320 | goto out; |
| 321 | } |
| 322 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 323 | ipv6_addr_copy(&aca->aca_addr, addr); |
| 324 | aca->aca_idev = idev; |
| 325 | aca->aca_rt = rt; |
| 326 | aca->aca_users = 1; |
| 327 | /* aca_tstamp should be updated upon changes */ |
| 328 | aca->aca_cstamp = aca->aca_tstamp = jiffies; |
| 329 | atomic_set(&aca->aca_refcnt, 2); |
| 330 | spin_lock_init(&aca->aca_lock); |
| 331 | |
| 332 | aca->aca_next = idev->ac_list; |
| 333 | idev->ac_list = aca; |
| 334 | write_unlock_bh(&idev->lock); |
| 335 | |
| 336 | dst_hold(&rt->u.dst); |
Thomas Graf | 40e22e8 | 2006-08-22 00:00:45 -0700 | [diff] [blame] | 337 | if (ip6_ins_rt(rt)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 338 | dst_release(&rt->u.dst); |
| 339 | |
| 340 | addrconf_join_solict(dev, &aca->aca_addr); |
| 341 | |
| 342 | aca_put(aca); |
| 343 | return 0; |
| 344 | out: |
| 345 | write_unlock_bh(&idev->lock); |
| 346 | in6_dev_put(idev); |
| 347 | return err; |
| 348 | } |
| 349 | |
| 350 | /* |
| 351 | * device anycast group decrement |
| 352 | */ |
| 353 | int __ipv6_dev_ac_dec(struct inet6_dev *idev, struct in6_addr *addr) |
| 354 | { |
| 355 | struct ifacaddr6 *aca, *prev_aca; |
| 356 | |
| 357 | write_lock_bh(&idev->lock); |
| 358 | prev_aca = NULL; |
| 359 | for (aca = idev->ac_list; aca; aca = aca->aca_next) { |
| 360 | if (ipv6_addr_equal(&aca->aca_addr, addr)) |
| 361 | break; |
| 362 | prev_aca = aca; |
| 363 | } |
| 364 | if (!aca) { |
| 365 | write_unlock_bh(&idev->lock); |
| 366 | return -ENOENT; |
| 367 | } |
| 368 | if (--aca->aca_users > 0) { |
| 369 | write_unlock_bh(&idev->lock); |
| 370 | return 0; |
| 371 | } |
| 372 | if (prev_aca) |
| 373 | prev_aca->aca_next = aca->aca_next; |
| 374 | else |
| 375 | idev->ac_list = aca->aca_next; |
| 376 | write_unlock_bh(&idev->lock); |
| 377 | addrconf_leave_solict(idev, &aca->aca_addr); |
| 378 | |
| 379 | dst_hold(&aca->aca_rt->u.dst); |
David S. Miller | 72d3b2c | 2006-08-22 00:13:07 -0700 | [diff] [blame] | 380 | if (ip6_del_rt(aca->aca_rt)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 381 | dst_free(&aca->aca_rt->u.dst); |
| 382 | else |
| 383 | dst_release(&aca->aca_rt->u.dst); |
| 384 | |
| 385 | aca_put(aca); |
| 386 | return 0; |
| 387 | } |
| 388 | |
| 389 | static int ipv6_dev_ac_dec(struct net_device *dev, struct in6_addr *addr) |
| 390 | { |
| 391 | int ret; |
| 392 | struct inet6_dev *idev = in6_dev_get(dev); |
| 393 | if (idev == NULL) |
| 394 | return -ENODEV; |
| 395 | ret = __ipv6_dev_ac_dec(idev, addr); |
| 396 | in6_dev_put(idev); |
| 397 | return ret; |
| 398 | } |
YOSHIFUJI Hideaki | 1ab1457 | 2007-02-09 23:24:49 +0900 | [diff] [blame] | 399 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 400 | /* |
| 401 | * check if the interface has this anycast address |
| 402 | */ |
| 403 | static int ipv6_chk_acast_dev(struct net_device *dev, struct in6_addr *addr) |
| 404 | { |
| 405 | struct inet6_dev *idev; |
| 406 | struct ifacaddr6 *aca; |
| 407 | |
| 408 | idev = in6_dev_get(dev); |
| 409 | if (idev) { |
| 410 | read_lock_bh(&idev->lock); |
| 411 | for (aca = idev->ac_list; aca; aca = aca->aca_next) |
| 412 | if (ipv6_addr_equal(&aca->aca_addr, addr)) |
| 413 | break; |
| 414 | read_unlock_bh(&idev->lock); |
| 415 | in6_dev_put(idev); |
| 416 | return aca != 0; |
| 417 | } |
| 418 | return 0; |
| 419 | } |
| 420 | |
| 421 | /* |
| 422 | * check if given interface (or any, if dev==0) has this anycast address |
| 423 | */ |
| 424 | int ipv6_chk_acast_addr(struct net_device *dev, struct in6_addr *addr) |
| 425 | { |
| 426 | if (dev) |
| 427 | return ipv6_chk_acast_dev(dev, addr); |
| 428 | read_lock(&dev_base_lock); |
| 429 | for (dev=dev_base; dev; dev=dev->next) |
| 430 | if (ipv6_chk_acast_dev(dev, addr)) |
| 431 | break; |
| 432 | read_unlock(&dev_base_lock); |
| 433 | return dev != 0; |
| 434 | } |
| 435 | |
| 436 | |
| 437 | #ifdef CONFIG_PROC_FS |
| 438 | struct ac6_iter_state { |
| 439 | struct net_device *dev; |
| 440 | struct inet6_dev *idev; |
| 441 | }; |
| 442 | |
| 443 | #define ac6_seq_private(seq) ((struct ac6_iter_state *)(seq)->private) |
| 444 | |
| 445 | static inline struct ifacaddr6 *ac6_get_first(struct seq_file *seq) |
| 446 | { |
| 447 | struct ifacaddr6 *im = NULL; |
| 448 | struct ac6_iter_state *state = ac6_seq_private(seq); |
| 449 | |
| 450 | for (state->dev = dev_base, state->idev = NULL; |
| 451 | state->dev; |
| 452 | state->dev = state->dev->next) { |
| 453 | struct inet6_dev *idev; |
| 454 | idev = in6_dev_get(state->dev); |
| 455 | if (!idev) |
| 456 | continue; |
| 457 | read_lock_bh(&idev->lock); |
| 458 | im = idev->ac_list; |
| 459 | if (im) { |
| 460 | state->idev = idev; |
| 461 | break; |
| 462 | } |
| 463 | read_unlock_bh(&idev->lock); |
| 464 | } |
| 465 | return im; |
| 466 | } |
| 467 | |
| 468 | static struct ifacaddr6 *ac6_get_next(struct seq_file *seq, struct ifacaddr6 *im) |
| 469 | { |
| 470 | struct ac6_iter_state *state = ac6_seq_private(seq); |
| 471 | |
| 472 | im = im->aca_next; |
| 473 | while (!im) { |
| 474 | if (likely(state->idev != NULL)) { |
| 475 | read_unlock_bh(&state->idev->lock); |
| 476 | in6_dev_put(state->idev); |
| 477 | } |
| 478 | state->dev = state->dev->next; |
| 479 | if (!state->dev) { |
| 480 | state->idev = NULL; |
| 481 | break; |
| 482 | } |
| 483 | state->idev = in6_dev_get(state->dev); |
| 484 | if (!state->idev) |
| 485 | continue; |
| 486 | read_lock_bh(&state->idev->lock); |
| 487 | im = state->idev->ac_list; |
| 488 | } |
| 489 | return im; |
| 490 | } |
| 491 | |
| 492 | static struct ifacaddr6 *ac6_get_idx(struct seq_file *seq, loff_t pos) |
| 493 | { |
| 494 | struct ifacaddr6 *im = ac6_get_first(seq); |
| 495 | if (im) |
| 496 | while (pos && (im = ac6_get_next(seq, im)) != NULL) |
| 497 | --pos; |
| 498 | return pos ? NULL : im; |
| 499 | } |
| 500 | |
| 501 | static void *ac6_seq_start(struct seq_file *seq, loff_t *pos) |
| 502 | { |
| 503 | read_lock(&dev_base_lock); |
| 504 | return ac6_get_idx(seq, *pos); |
| 505 | } |
| 506 | |
| 507 | static void *ac6_seq_next(struct seq_file *seq, void *v, loff_t *pos) |
| 508 | { |
| 509 | struct ifacaddr6 *im; |
| 510 | im = ac6_get_next(seq, v); |
| 511 | ++*pos; |
| 512 | return im; |
| 513 | } |
| 514 | |
| 515 | static void ac6_seq_stop(struct seq_file *seq, void *v) |
| 516 | { |
| 517 | struct ac6_iter_state *state = ac6_seq_private(seq); |
| 518 | if (likely(state->idev != NULL)) { |
| 519 | read_unlock_bh(&state->idev->lock); |
| 520 | in6_dev_put(state->idev); |
| 521 | } |
| 522 | read_unlock(&dev_base_lock); |
| 523 | } |
| 524 | |
| 525 | static int ac6_seq_show(struct seq_file *seq, void *v) |
| 526 | { |
| 527 | struct ifacaddr6 *im = (struct ifacaddr6 *)v; |
| 528 | struct ac6_iter_state *state = ac6_seq_private(seq); |
| 529 | |
| 530 | seq_printf(seq, |
YOSHIFUJI Hideaki | 9343e79 | 2006-01-17 02:10:53 -0800 | [diff] [blame] | 531 | "%-4d %-15s " NIP6_SEQFMT " %5d\n", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 532 | state->dev->ifindex, state->dev->name, |
| 533 | NIP6(im->aca_addr), |
| 534 | im->aca_users); |
| 535 | return 0; |
| 536 | } |
| 537 | |
| 538 | static struct seq_operations ac6_seq_ops = { |
| 539 | .start = ac6_seq_start, |
| 540 | .next = ac6_seq_next, |
| 541 | .stop = ac6_seq_stop, |
| 542 | .show = ac6_seq_show, |
| 543 | }; |
| 544 | |
| 545 | static int ac6_seq_open(struct inode *inode, struct file *file) |
| 546 | { |
| 547 | struct seq_file *seq; |
| 548 | int rc = -ENOMEM; |
Ingo Oeser | 0c600ed | 2006-03-20 23:01:32 -0800 | [diff] [blame] | 549 | struct ac6_iter_state *s = kzalloc(sizeof(*s), GFP_KERNEL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 550 | |
| 551 | if (!s) |
| 552 | goto out; |
| 553 | |
| 554 | rc = seq_open(file, &ac6_seq_ops); |
| 555 | if (rc) |
| 556 | goto out_kfree; |
| 557 | |
| 558 | seq = file->private_data; |
| 559 | seq->private = s; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 560 | out: |
| 561 | return rc; |
| 562 | out_kfree: |
| 563 | kfree(s); |
| 564 | goto out; |
| 565 | } |
| 566 | |
Arjan van de Ven | 9a32144 | 2007-02-12 00:55:35 -0800 | [diff] [blame] | 567 | static const struct file_operations ac6_seq_fops = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 568 | .owner = THIS_MODULE, |
| 569 | .open = ac6_seq_open, |
| 570 | .read = seq_read, |
| 571 | .llseek = seq_lseek, |
| 572 | .release = seq_release_private, |
| 573 | }; |
| 574 | |
| 575 | int __init ac6_proc_init(void) |
| 576 | { |
| 577 | if (!proc_net_fops_create("anycast6", S_IRUGO, &ac6_seq_fops)) |
| 578 | return -ENOMEM; |
| 579 | |
| 580 | return 0; |
| 581 | } |
| 582 | |
| 583 | void ac6_proc_exit(void) |
| 584 | { |
| 585 | proc_net_remove("anycast6"); |
| 586 | } |
| 587 | #endif |
| 588 | |