Steffen Klassert | ed1efb2 | 2013-08-19 08:07:34 +0200 | [diff] [blame] | 1 | /* |
| 2 | * IPv6 virtual tunneling interface |
| 3 | * |
| 4 | * Copyright (C) 2013 secunet Security Networks AG |
| 5 | * |
| 6 | * Author: |
| 7 | * Steffen Klassert <steffen.klassert@secunet.com> |
| 8 | * |
| 9 | * Based on: |
| 10 | * net/ipv6/ip6_tunnel.c |
| 11 | * |
| 12 | * This program is free software; you can redistribute it and/or |
| 13 | * modify it under the terms of the GNU General Public License |
| 14 | * as published by the Free Software Foundation; either version |
| 15 | * 2 of the License, or (at your option) any later version. |
| 16 | */ |
| 17 | |
| 18 | #include <linux/module.h> |
| 19 | #include <linux/capability.h> |
| 20 | #include <linux/errno.h> |
| 21 | #include <linux/types.h> |
| 22 | #include <linux/sockios.h> |
| 23 | #include <linux/icmp.h> |
| 24 | #include <linux/if.h> |
| 25 | #include <linux/in.h> |
| 26 | #include <linux/ip.h> |
| 27 | #include <linux/if_tunnel.h> |
| 28 | #include <linux/net.h> |
| 29 | #include <linux/in6.h> |
| 30 | #include <linux/netdevice.h> |
| 31 | #include <linux/if_arp.h> |
| 32 | #include <linux/icmpv6.h> |
| 33 | #include <linux/init.h> |
| 34 | #include <linux/route.h> |
| 35 | #include <linux/rtnetlink.h> |
| 36 | #include <linux/netfilter_ipv6.h> |
| 37 | #include <linux/slab.h> |
| 38 | #include <linux/hash.h> |
| 39 | |
| 40 | #include <linux/uaccess.h> |
| 41 | #include <linux/atomic.h> |
| 42 | |
| 43 | #include <net/icmp.h> |
| 44 | #include <net/ip.h> |
| 45 | #include <net/ip_tunnels.h> |
| 46 | #include <net/ipv6.h> |
| 47 | #include <net/ip6_route.h> |
| 48 | #include <net/addrconf.h> |
| 49 | #include <net/ip6_tunnel.h> |
| 50 | #include <net/xfrm.h> |
| 51 | #include <net/net_namespace.h> |
| 52 | #include <net/netns/generic.h> |
| 53 | |
| 54 | #define HASH_SIZE_SHIFT 5 |
| 55 | #define HASH_SIZE (1 << HASH_SIZE_SHIFT) |
| 56 | |
| 57 | static u32 HASH(const struct in6_addr *addr1, const struct in6_addr *addr2) |
| 58 | { |
| 59 | u32 hash = ipv6_addr_hash(addr1) ^ ipv6_addr_hash(addr2); |
| 60 | |
| 61 | return hash_32(hash, HASH_SIZE_SHIFT); |
| 62 | } |
| 63 | |
| 64 | static int vti6_dev_init(struct net_device *dev); |
| 65 | static void vti6_dev_setup(struct net_device *dev); |
| 66 | static struct rtnl_link_ops vti6_link_ops __read_mostly; |
| 67 | |
| 68 | static int vti6_net_id __read_mostly; |
| 69 | struct vti6_net { |
| 70 | /* the vti6 tunnel fallback device */ |
| 71 | struct net_device *fb_tnl_dev; |
| 72 | /* lists for storing tunnels in use */ |
| 73 | struct ip6_tnl __rcu *tnls_r_l[HASH_SIZE]; |
| 74 | struct ip6_tnl __rcu *tnls_wc[1]; |
| 75 | struct ip6_tnl __rcu **tnls[2]; |
| 76 | }; |
| 77 | |
| 78 | static struct net_device_stats *vti6_get_stats(struct net_device *dev) |
| 79 | { |
| 80 | struct pcpu_tstats sum = { 0 }; |
| 81 | int i; |
| 82 | |
| 83 | for_each_possible_cpu(i) { |
| 84 | const struct pcpu_tstats *tstats = per_cpu_ptr(dev->tstats, i); |
| 85 | |
| 86 | sum.rx_packets += tstats->rx_packets; |
| 87 | sum.rx_bytes += tstats->rx_bytes; |
| 88 | sum.tx_packets += tstats->tx_packets; |
| 89 | sum.tx_bytes += tstats->tx_bytes; |
| 90 | } |
| 91 | dev->stats.rx_packets = sum.rx_packets; |
| 92 | dev->stats.rx_bytes = sum.rx_bytes; |
| 93 | dev->stats.tx_packets = sum.tx_packets; |
| 94 | dev->stats.tx_bytes = sum.tx_bytes; |
| 95 | return &dev->stats; |
| 96 | } |
| 97 | |
| 98 | #define for_each_vti6_tunnel_rcu(start) \ |
| 99 | for (t = rcu_dereference(start); t; t = rcu_dereference(t->next)) |
| 100 | |
| 101 | /** |
| 102 | * vti6_tnl_lookup - fetch tunnel matching the end-point addresses |
| 103 | * @net: network namespace |
| 104 | * @remote: the address of the tunnel exit-point |
| 105 | * @local: the address of the tunnel entry-point |
| 106 | * |
| 107 | * Return: |
| 108 | * tunnel matching given end-points if found, |
| 109 | * else fallback tunnel if its device is up, |
| 110 | * else %NULL |
| 111 | **/ |
| 112 | static struct ip6_tnl * |
| 113 | vti6_tnl_lookup(struct net *net, const struct in6_addr *remote, |
| 114 | const struct in6_addr *local) |
| 115 | { |
| 116 | unsigned int hash = HASH(remote, local); |
| 117 | struct ip6_tnl *t; |
| 118 | struct vti6_net *ip6n = net_generic(net, vti6_net_id); |
| 119 | |
| 120 | for_each_vti6_tunnel_rcu(ip6n->tnls_r_l[hash]) { |
| 121 | if (ipv6_addr_equal(local, &t->parms.laddr) && |
| 122 | ipv6_addr_equal(remote, &t->parms.raddr) && |
| 123 | (t->dev->flags & IFF_UP)) |
| 124 | return t; |
| 125 | } |
| 126 | t = rcu_dereference(ip6n->tnls_wc[0]); |
| 127 | if (t && (t->dev->flags & IFF_UP)) |
| 128 | return t; |
| 129 | |
| 130 | return NULL; |
| 131 | } |
| 132 | |
| 133 | /** |
| 134 | * vti6_tnl_bucket - get head of list matching given tunnel parameters |
| 135 | * @p: parameters containing tunnel end-points |
| 136 | * |
| 137 | * Description: |
| 138 | * vti6_tnl_bucket() returns the head of the list matching the |
| 139 | * &struct in6_addr entries laddr and raddr in @p. |
| 140 | * |
| 141 | * Return: head of IPv6 tunnel list |
| 142 | **/ |
| 143 | static struct ip6_tnl __rcu ** |
| 144 | vti6_tnl_bucket(struct vti6_net *ip6n, const struct __ip6_tnl_parm *p) |
| 145 | { |
| 146 | const struct in6_addr *remote = &p->raddr; |
| 147 | const struct in6_addr *local = &p->laddr; |
| 148 | unsigned int h = 0; |
| 149 | int prio = 0; |
| 150 | |
| 151 | if (!ipv6_addr_any(remote) || !ipv6_addr_any(local)) { |
| 152 | prio = 1; |
| 153 | h = HASH(remote, local); |
| 154 | } |
| 155 | return &ip6n->tnls[prio][h]; |
| 156 | } |
| 157 | |
| 158 | static void |
| 159 | vti6_tnl_link(struct vti6_net *ip6n, struct ip6_tnl *t) |
| 160 | { |
| 161 | struct ip6_tnl __rcu **tp = vti6_tnl_bucket(ip6n, &t->parms); |
| 162 | |
| 163 | rcu_assign_pointer(t->next , rtnl_dereference(*tp)); |
| 164 | rcu_assign_pointer(*tp, t); |
| 165 | } |
| 166 | |
| 167 | static void |
| 168 | vti6_tnl_unlink(struct vti6_net *ip6n, struct ip6_tnl *t) |
| 169 | { |
| 170 | struct ip6_tnl __rcu **tp; |
| 171 | struct ip6_tnl *iter; |
| 172 | |
| 173 | for (tp = vti6_tnl_bucket(ip6n, &t->parms); |
| 174 | (iter = rtnl_dereference(*tp)) != NULL; |
| 175 | tp = &iter->next) { |
| 176 | if (t == iter) { |
| 177 | rcu_assign_pointer(*tp, t->next); |
| 178 | break; |
| 179 | } |
| 180 | } |
| 181 | } |
| 182 | |
| 183 | static void vti6_dev_free(struct net_device *dev) |
| 184 | { |
| 185 | free_percpu(dev->tstats); |
| 186 | free_netdev(dev); |
| 187 | } |
| 188 | |
| 189 | static int vti6_tnl_create2(struct net_device *dev) |
| 190 | { |
| 191 | struct ip6_tnl *t = netdev_priv(dev); |
| 192 | struct net *net = dev_net(dev); |
| 193 | struct vti6_net *ip6n = net_generic(net, vti6_net_id); |
| 194 | int err; |
| 195 | |
| 196 | err = vti6_dev_init(dev); |
| 197 | if (err < 0) |
| 198 | goto out; |
| 199 | |
| 200 | err = register_netdevice(dev); |
| 201 | if (err < 0) |
| 202 | goto out; |
| 203 | |
| 204 | strcpy(t->parms.name, dev->name); |
| 205 | dev->rtnl_link_ops = &vti6_link_ops; |
| 206 | |
| 207 | dev_hold(dev); |
| 208 | vti6_tnl_link(ip6n, t); |
| 209 | |
| 210 | return 0; |
| 211 | |
| 212 | out: |
| 213 | return err; |
| 214 | } |
| 215 | |
| 216 | static struct ip6_tnl *vti6_tnl_create(struct net *net, struct __ip6_tnl_parm *p) |
| 217 | { |
| 218 | struct net_device *dev; |
| 219 | struct ip6_tnl *t; |
| 220 | char name[IFNAMSIZ]; |
| 221 | int err; |
| 222 | |
| 223 | if (p->name[0]) |
| 224 | strlcpy(name, p->name, IFNAMSIZ); |
| 225 | else |
| 226 | sprintf(name, "ip6_vti%%d"); |
| 227 | |
| 228 | dev = alloc_netdev(sizeof(*t), name, vti6_dev_setup); |
| 229 | if (dev == NULL) |
| 230 | goto failed; |
| 231 | |
| 232 | dev_net_set(dev, net); |
| 233 | |
| 234 | t = netdev_priv(dev); |
| 235 | t->parms = *p; |
| 236 | t->net = dev_net(dev); |
| 237 | |
| 238 | err = vti6_tnl_create2(dev); |
| 239 | if (err < 0) |
| 240 | goto failed_free; |
| 241 | |
| 242 | return t; |
| 243 | |
| 244 | failed_free: |
| 245 | vti6_dev_free(dev); |
| 246 | failed: |
| 247 | return NULL; |
| 248 | } |
| 249 | |
| 250 | /** |
| 251 | * vti6_locate - find or create tunnel matching given parameters |
| 252 | * @net: network namespace |
| 253 | * @p: tunnel parameters |
| 254 | * @create: != 0 if allowed to create new tunnel if no match found |
| 255 | * |
| 256 | * Description: |
| 257 | * vti6_locate() first tries to locate an existing tunnel |
| 258 | * based on @parms. If this is unsuccessful, but @create is set a new |
| 259 | * tunnel device is created and registered for use. |
| 260 | * |
| 261 | * Return: |
| 262 | * matching tunnel or NULL |
| 263 | **/ |
| 264 | static struct ip6_tnl *vti6_locate(struct net *net, struct __ip6_tnl_parm *p, |
| 265 | int create) |
| 266 | { |
| 267 | const struct in6_addr *remote = &p->raddr; |
| 268 | const struct in6_addr *local = &p->laddr; |
| 269 | struct ip6_tnl __rcu **tp; |
| 270 | struct ip6_tnl *t; |
| 271 | struct vti6_net *ip6n = net_generic(net, vti6_net_id); |
| 272 | |
| 273 | for (tp = vti6_tnl_bucket(ip6n, p); |
| 274 | (t = rtnl_dereference(*tp)) != NULL; |
| 275 | tp = &t->next) { |
| 276 | if (ipv6_addr_equal(local, &t->parms.laddr) && |
| 277 | ipv6_addr_equal(remote, &t->parms.raddr)) |
| 278 | return t; |
| 279 | } |
| 280 | if (!create) |
| 281 | return NULL; |
| 282 | return vti6_tnl_create(net, p); |
| 283 | } |
| 284 | |
| 285 | /** |
| 286 | * vti6_dev_uninit - tunnel device uninitializer |
| 287 | * @dev: the device to be destroyed |
| 288 | * |
| 289 | * Description: |
| 290 | * vti6_dev_uninit() removes tunnel from its list |
| 291 | **/ |
| 292 | static void vti6_dev_uninit(struct net_device *dev) |
| 293 | { |
| 294 | struct ip6_tnl *t = netdev_priv(dev); |
| 295 | struct net *net = dev_net(dev); |
| 296 | struct vti6_net *ip6n = net_generic(net, vti6_net_id); |
| 297 | |
| 298 | if (dev == ip6n->fb_tnl_dev) |
| 299 | RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL); |
| 300 | else |
| 301 | vti6_tnl_unlink(ip6n, t); |
| 302 | ip6_tnl_dst_reset(t); |
| 303 | dev_put(dev); |
| 304 | } |
| 305 | |
| 306 | static int vti6_rcv(struct sk_buff *skb) |
| 307 | { |
| 308 | struct ip6_tnl *t; |
| 309 | const struct ipv6hdr *ipv6h = ipv6_hdr(skb); |
| 310 | |
| 311 | rcu_read_lock(); |
| 312 | |
| 313 | if ((t = vti6_tnl_lookup(dev_net(skb->dev), &ipv6h->saddr, |
| 314 | &ipv6h->daddr)) != NULL) { |
| 315 | struct pcpu_tstats *tstats; |
| 316 | |
| 317 | if (t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) { |
| 318 | rcu_read_unlock(); |
| 319 | goto discard; |
| 320 | } |
| 321 | |
| 322 | if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) { |
| 323 | rcu_read_unlock(); |
| 324 | return 0; |
| 325 | } |
| 326 | |
| 327 | if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr)) { |
| 328 | t->dev->stats.rx_dropped++; |
| 329 | rcu_read_unlock(); |
| 330 | goto discard; |
| 331 | } |
| 332 | |
| 333 | tstats = this_cpu_ptr(t->dev->tstats); |
| 334 | tstats->rx_packets++; |
| 335 | tstats->rx_bytes += skb->len; |
| 336 | |
| 337 | skb->mark = 0; |
| 338 | secpath_reset(skb); |
| 339 | skb->dev = t->dev; |
| 340 | |
| 341 | rcu_read_unlock(); |
| 342 | return 0; |
| 343 | } |
| 344 | rcu_read_unlock(); |
| 345 | return 1; |
| 346 | |
| 347 | discard: |
| 348 | kfree_skb(skb); |
| 349 | return 0; |
| 350 | } |
| 351 | |
| 352 | /** |
| 353 | * vti6_addr_conflict - compare packet addresses to tunnel's own |
| 354 | * @t: the outgoing tunnel device |
| 355 | * @hdr: IPv6 header from the incoming packet |
| 356 | * |
| 357 | * Description: |
| 358 | * Avoid trivial tunneling loop by checking that tunnel exit-point |
| 359 | * doesn't match source of incoming packet. |
| 360 | * |
| 361 | * Return: |
| 362 | * 1 if conflict, |
| 363 | * 0 else |
| 364 | **/ |
| 365 | static inline bool |
| 366 | vti6_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr) |
| 367 | { |
| 368 | return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr); |
| 369 | } |
| 370 | |
| 371 | /** |
| 372 | * vti6_xmit - send a packet |
| 373 | * @skb: the outgoing socket buffer |
| 374 | * @dev: the outgoing tunnel device |
| 375 | **/ |
| 376 | static int vti6_xmit(struct sk_buff *skb, struct net_device *dev) |
| 377 | { |
| 378 | struct net *net = dev_net(dev); |
| 379 | struct ip6_tnl *t = netdev_priv(dev); |
| 380 | struct net_device_stats *stats = &t->dev->stats; |
| 381 | struct dst_entry *dst = NULL, *ndst = NULL; |
| 382 | struct flowi6 fl6; |
| 383 | struct ipv6hdr *ipv6h = ipv6_hdr(skb); |
| 384 | struct net_device *tdev; |
| 385 | int err = -1; |
| 386 | |
| 387 | if ((t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) || |
| 388 | !ip6_tnl_xmit_ctl(t) || vti6_addr_conflict(t, ipv6h)) |
| 389 | return err; |
| 390 | |
| 391 | dst = ip6_tnl_dst_check(t); |
| 392 | if (!dst) { |
| 393 | memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); |
| 394 | |
| 395 | ndst = ip6_route_output(net, NULL, &fl6); |
| 396 | |
| 397 | if (ndst->error) |
| 398 | goto tx_err_link_failure; |
| 399 | ndst = xfrm_lookup(net, ndst, flowi6_to_flowi(&fl6), NULL, 0); |
| 400 | if (IS_ERR(ndst)) { |
| 401 | err = PTR_ERR(ndst); |
| 402 | ndst = NULL; |
| 403 | goto tx_err_link_failure; |
| 404 | } |
| 405 | dst = ndst; |
| 406 | } |
| 407 | |
| 408 | if (!dst->xfrm || dst->xfrm->props.mode != XFRM_MODE_TUNNEL) |
| 409 | goto tx_err_link_failure; |
| 410 | |
| 411 | tdev = dst->dev; |
| 412 | |
| 413 | if (tdev == dev) { |
| 414 | stats->collisions++; |
| 415 | net_warn_ratelimited("%s: Local routing loop detected!\n", |
| 416 | t->parms.name); |
| 417 | goto tx_err_dst_release; |
| 418 | } |
| 419 | |
| 420 | |
| 421 | skb_dst_drop(skb); |
| 422 | skb_dst_set_noref(skb, dst); |
| 423 | |
| 424 | ip6tunnel_xmit(skb, dev); |
| 425 | if (ndst) { |
| 426 | dev->mtu = dst_mtu(ndst); |
| 427 | ip6_tnl_dst_store(t, ndst); |
| 428 | } |
| 429 | |
| 430 | return 0; |
| 431 | tx_err_link_failure: |
| 432 | stats->tx_carrier_errors++; |
| 433 | dst_link_failure(skb); |
| 434 | tx_err_dst_release: |
| 435 | dst_release(ndst); |
| 436 | return err; |
| 437 | } |
| 438 | |
| 439 | static netdev_tx_t |
| 440 | vti6_tnl_xmit(struct sk_buff *skb, struct net_device *dev) |
| 441 | { |
| 442 | struct ip6_tnl *t = netdev_priv(dev); |
| 443 | struct net_device_stats *stats = &t->dev->stats; |
| 444 | int ret; |
| 445 | |
| 446 | switch (skb->protocol) { |
| 447 | case htons(ETH_P_IPV6): |
| 448 | ret = vti6_xmit(skb, dev); |
| 449 | break; |
| 450 | default: |
| 451 | goto tx_err; |
| 452 | } |
| 453 | |
| 454 | if (ret < 0) |
| 455 | goto tx_err; |
| 456 | |
| 457 | return NETDEV_TX_OK; |
| 458 | |
| 459 | tx_err: |
| 460 | stats->tx_errors++; |
| 461 | stats->tx_dropped++; |
| 462 | kfree_skb(skb); |
| 463 | return NETDEV_TX_OK; |
| 464 | } |
| 465 | |
| 466 | static void vti6_link_config(struct ip6_tnl *t) |
| 467 | { |
| 468 | struct dst_entry *dst; |
| 469 | struct net_device *dev = t->dev; |
| 470 | struct __ip6_tnl_parm *p = &t->parms; |
| 471 | struct flowi6 *fl6 = &t->fl.u.ip6; |
| 472 | |
| 473 | memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr)); |
| 474 | memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr)); |
| 475 | |
| 476 | /* Set up flowi template */ |
| 477 | fl6->saddr = p->laddr; |
| 478 | fl6->daddr = p->raddr; |
| 479 | fl6->flowi6_oif = p->link; |
| 480 | fl6->flowi6_mark = be32_to_cpu(p->i_key); |
| 481 | fl6->flowi6_proto = p->proto; |
| 482 | fl6->flowlabel = 0; |
| 483 | |
| 484 | p->flags &= ~(IP6_TNL_F_CAP_XMIT | IP6_TNL_F_CAP_RCV | |
| 485 | IP6_TNL_F_CAP_PER_PACKET); |
| 486 | p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr); |
| 487 | |
| 488 | if (p->flags & IP6_TNL_F_CAP_XMIT && p->flags & IP6_TNL_F_CAP_RCV) |
| 489 | dev->flags |= IFF_POINTOPOINT; |
| 490 | else |
| 491 | dev->flags &= ~IFF_POINTOPOINT; |
| 492 | |
| 493 | dev->iflink = p->link; |
| 494 | |
| 495 | if (p->flags & IP6_TNL_F_CAP_XMIT) { |
| 496 | |
| 497 | dst = ip6_route_output(dev_net(dev), NULL, fl6); |
| 498 | if (dst->error) |
| 499 | return; |
| 500 | |
| 501 | dst = xfrm_lookup(dev_net(dev), dst, flowi6_to_flowi(fl6), |
| 502 | NULL, 0); |
| 503 | if (IS_ERR(dst)) |
| 504 | return; |
| 505 | |
| 506 | if (dst->dev) { |
| 507 | dev->hard_header_len = dst->dev->hard_header_len; |
| 508 | |
| 509 | dev->mtu = dst_mtu(dst); |
| 510 | |
| 511 | if (dev->mtu < IPV6_MIN_MTU) |
| 512 | dev->mtu = IPV6_MIN_MTU; |
| 513 | } |
| 514 | dst_release(dst); |
| 515 | } |
| 516 | } |
| 517 | |
| 518 | /** |
| 519 | * vti6_tnl_change - update the tunnel parameters |
| 520 | * @t: tunnel to be changed |
| 521 | * @p: tunnel configuration parameters |
| 522 | * |
| 523 | * Description: |
| 524 | * vti6_tnl_change() updates the tunnel parameters |
| 525 | **/ |
| 526 | static int |
| 527 | vti6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p) |
| 528 | { |
| 529 | t->parms.laddr = p->laddr; |
| 530 | t->parms.raddr = p->raddr; |
| 531 | t->parms.link = p->link; |
| 532 | t->parms.i_key = p->i_key; |
| 533 | t->parms.o_key = p->o_key; |
| 534 | t->parms.proto = p->proto; |
| 535 | ip6_tnl_dst_reset(t); |
| 536 | vti6_link_config(t); |
| 537 | return 0; |
| 538 | } |
| 539 | |
| 540 | static int vti6_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p) |
| 541 | { |
| 542 | struct net *net = dev_net(t->dev); |
| 543 | struct vti6_net *ip6n = net_generic(net, vti6_net_id); |
| 544 | int err; |
| 545 | |
| 546 | vti6_tnl_unlink(ip6n, t); |
| 547 | synchronize_net(); |
| 548 | err = vti6_tnl_change(t, p); |
| 549 | vti6_tnl_link(ip6n, t); |
| 550 | netdev_state_change(t->dev); |
| 551 | return err; |
| 552 | } |
| 553 | |
| 554 | static void |
| 555 | vti6_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm2 *u) |
| 556 | { |
| 557 | p->laddr = u->laddr; |
| 558 | p->raddr = u->raddr; |
| 559 | p->link = u->link; |
| 560 | p->i_key = u->i_key; |
| 561 | p->o_key = u->o_key; |
| 562 | p->proto = u->proto; |
| 563 | |
| 564 | memcpy(p->name, u->name, sizeof(u->name)); |
| 565 | } |
| 566 | |
| 567 | static void |
| 568 | vti6_parm_to_user(struct ip6_tnl_parm2 *u, const struct __ip6_tnl_parm *p) |
| 569 | { |
| 570 | u->laddr = p->laddr; |
| 571 | u->raddr = p->raddr; |
| 572 | u->link = p->link; |
| 573 | u->i_key = p->i_key; |
| 574 | u->o_key = p->o_key; |
| 575 | u->proto = p->proto; |
| 576 | |
| 577 | memcpy(u->name, p->name, sizeof(u->name)); |
| 578 | } |
| 579 | |
| 580 | /** |
| 581 | * vti6_tnl_ioctl - configure vti6 tunnels from userspace |
| 582 | * @dev: virtual device associated with tunnel |
| 583 | * @ifr: parameters passed from userspace |
| 584 | * @cmd: command to be performed |
| 585 | * |
| 586 | * Description: |
| 587 | * vti6_ioctl() is used for managing vti6 tunnels |
| 588 | * from userspace. |
| 589 | * |
| 590 | * The possible commands are the following: |
| 591 | * %SIOCGETTUNNEL: get tunnel parameters for device |
| 592 | * %SIOCADDTUNNEL: add tunnel matching given tunnel parameters |
| 593 | * %SIOCCHGTUNNEL: change tunnel parameters to those given |
| 594 | * %SIOCDELTUNNEL: delete tunnel |
| 595 | * |
| 596 | * The fallback device "ip6_vti0", created during module |
| 597 | * initialization, can be used for creating other tunnel devices. |
| 598 | * |
| 599 | * Return: |
| 600 | * 0 on success, |
| 601 | * %-EFAULT if unable to copy data to or from userspace, |
| 602 | * %-EPERM if current process hasn't %CAP_NET_ADMIN set |
| 603 | * %-EINVAL if passed tunnel parameters are invalid, |
| 604 | * %-EEXIST if changing a tunnel's parameters would cause a conflict |
| 605 | * %-ENODEV if attempting to change or delete a nonexisting device |
| 606 | **/ |
| 607 | static int |
| 608 | vti6_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) |
| 609 | { |
| 610 | int err = 0; |
| 611 | struct ip6_tnl_parm2 p; |
| 612 | struct __ip6_tnl_parm p1; |
| 613 | struct ip6_tnl *t = NULL; |
| 614 | struct net *net = dev_net(dev); |
| 615 | struct vti6_net *ip6n = net_generic(net, vti6_net_id); |
| 616 | |
| 617 | switch (cmd) { |
| 618 | case SIOCGETTUNNEL: |
| 619 | if (dev == ip6n->fb_tnl_dev) { |
| 620 | if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) { |
| 621 | err = -EFAULT; |
| 622 | break; |
| 623 | } |
| 624 | vti6_parm_from_user(&p1, &p); |
| 625 | t = vti6_locate(net, &p1, 0); |
| 626 | } else { |
| 627 | memset(&p, 0, sizeof(p)); |
| 628 | } |
| 629 | if (t == NULL) |
| 630 | t = netdev_priv(dev); |
| 631 | vti6_parm_to_user(&p, &t->parms); |
| 632 | if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) |
| 633 | err = -EFAULT; |
| 634 | break; |
| 635 | case SIOCADDTUNNEL: |
| 636 | case SIOCCHGTUNNEL: |
| 637 | err = -EPERM; |
| 638 | if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) |
| 639 | break; |
| 640 | err = -EFAULT; |
| 641 | if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) |
| 642 | break; |
| 643 | err = -EINVAL; |
| 644 | if (p.proto != IPPROTO_IPV6 && p.proto != 0) |
| 645 | break; |
| 646 | vti6_parm_from_user(&p1, &p); |
| 647 | t = vti6_locate(net, &p1, cmd == SIOCADDTUNNEL); |
| 648 | if (dev != ip6n->fb_tnl_dev && cmd == SIOCCHGTUNNEL) { |
| 649 | if (t != NULL) { |
| 650 | if (t->dev != dev) { |
| 651 | err = -EEXIST; |
| 652 | break; |
| 653 | } |
| 654 | } else |
| 655 | t = netdev_priv(dev); |
| 656 | |
| 657 | err = vti6_update(t, &p1); |
| 658 | } |
| 659 | if (t) { |
| 660 | err = 0; |
| 661 | vti6_parm_to_user(&p, &t->parms); |
| 662 | if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) |
| 663 | err = -EFAULT; |
| 664 | |
| 665 | } else |
| 666 | err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT); |
| 667 | break; |
| 668 | case SIOCDELTUNNEL: |
| 669 | err = -EPERM; |
| 670 | if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) |
| 671 | break; |
| 672 | |
| 673 | if (dev == ip6n->fb_tnl_dev) { |
| 674 | err = -EFAULT; |
| 675 | if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) |
| 676 | break; |
| 677 | err = -ENOENT; |
| 678 | vti6_parm_from_user(&p1, &p); |
| 679 | t = vti6_locate(net, &p1, 0); |
| 680 | if (t == NULL) |
| 681 | break; |
| 682 | err = -EPERM; |
| 683 | if (t->dev == ip6n->fb_tnl_dev) |
| 684 | break; |
| 685 | dev = t->dev; |
| 686 | } |
| 687 | err = 0; |
| 688 | unregister_netdevice(dev); |
| 689 | break; |
| 690 | default: |
| 691 | err = -EINVAL; |
| 692 | } |
| 693 | return err; |
| 694 | } |
| 695 | |
| 696 | /** |
| 697 | * vti6_tnl_change_mtu - change mtu manually for tunnel device |
| 698 | * @dev: virtual device associated with tunnel |
| 699 | * @new_mtu: the new mtu |
| 700 | * |
| 701 | * Return: |
| 702 | * 0 on success, |
| 703 | * %-EINVAL if mtu too small |
| 704 | **/ |
| 705 | static int vti6_change_mtu(struct net_device *dev, int new_mtu) |
| 706 | { |
| 707 | if (new_mtu < IPV6_MIN_MTU) |
| 708 | return -EINVAL; |
| 709 | |
| 710 | dev->mtu = new_mtu; |
| 711 | return 0; |
| 712 | } |
| 713 | |
| 714 | static const struct net_device_ops vti6_netdev_ops = { |
| 715 | .ndo_uninit = vti6_dev_uninit, |
| 716 | .ndo_start_xmit = vti6_tnl_xmit, |
| 717 | .ndo_do_ioctl = vti6_ioctl, |
| 718 | .ndo_change_mtu = vti6_change_mtu, |
| 719 | .ndo_get_stats = vti6_get_stats, |
| 720 | }; |
| 721 | |
| 722 | /** |
| 723 | * vti6_dev_setup - setup virtual tunnel device |
| 724 | * @dev: virtual device associated with tunnel |
| 725 | * |
| 726 | * Description: |
| 727 | * Initialize function pointers and device parameters |
| 728 | **/ |
| 729 | static void vti6_dev_setup(struct net_device *dev) |
| 730 | { |
| 731 | struct ip6_tnl *t; |
| 732 | |
| 733 | dev->netdev_ops = &vti6_netdev_ops; |
| 734 | dev->destructor = vti6_dev_free; |
| 735 | |
| 736 | dev->type = ARPHRD_TUNNEL6; |
| 737 | dev->hard_header_len = LL_MAX_HEADER + sizeof(struct ipv6hdr); |
| 738 | dev->mtu = ETH_DATA_LEN; |
| 739 | t = netdev_priv(dev); |
| 740 | dev->flags |= IFF_NOARP; |
| 741 | dev->addr_len = sizeof(struct in6_addr); |
| 742 | dev->features |= NETIF_F_NETNS_LOCAL; |
| 743 | dev->priv_flags &= ~IFF_XMIT_DST_RELEASE; |
| 744 | } |
| 745 | |
| 746 | /** |
| 747 | * vti6_dev_init_gen - general initializer for all tunnel devices |
| 748 | * @dev: virtual device associated with tunnel |
| 749 | **/ |
| 750 | static inline int vti6_dev_init_gen(struct net_device *dev) |
| 751 | { |
| 752 | struct ip6_tnl *t = netdev_priv(dev); |
| 753 | |
| 754 | t->dev = dev; |
| 755 | t->net = dev_net(dev); |
| 756 | dev->tstats = alloc_percpu(struct pcpu_tstats); |
| 757 | if (!dev->tstats) |
| 758 | return -ENOMEM; |
| 759 | return 0; |
| 760 | } |
| 761 | |
| 762 | /** |
| 763 | * vti6_dev_init - initializer for all non fallback tunnel devices |
| 764 | * @dev: virtual device associated with tunnel |
| 765 | **/ |
| 766 | static int vti6_dev_init(struct net_device *dev) |
| 767 | { |
| 768 | struct ip6_tnl *t = netdev_priv(dev); |
| 769 | int err = vti6_dev_init_gen(dev); |
| 770 | |
| 771 | if (err) |
| 772 | return err; |
| 773 | vti6_link_config(t); |
| 774 | return 0; |
| 775 | } |
| 776 | |
| 777 | /** |
| 778 | * vti6_fb_tnl_dev_init - initializer for fallback tunnel device |
| 779 | * @dev: fallback device |
| 780 | * |
| 781 | * Return: 0 |
| 782 | **/ |
| 783 | static int __net_init vti6_fb_tnl_dev_init(struct net_device *dev) |
| 784 | { |
| 785 | struct ip6_tnl *t = netdev_priv(dev); |
| 786 | struct net *net = dev_net(dev); |
| 787 | struct vti6_net *ip6n = net_generic(net, vti6_net_id); |
| 788 | int err = vti6_dev_init_gen(dev); |
| 789 | |
| 790 | if (err) |
| 791 | return err; |
| 792 | |
| 793 | t->parms.proto = IPPROTO_IPV6; |
| 794 | dev_hold(dev); |
| 795 | |
| 796 | vti6_link_config(t); |
| 797 | |
| 798 | rcu_assign_pointer(ip6n->tnls_wc[0], t); |
| 799 | return 0; |
| 800 | } |
| 801 | |
| 802 | static int vti6_validate(struct nlattr *tb[], struct nlattr *data[]) |
| 803 | { |
| 804 | return 0; |
| 805 | } |
| 806 | |
| 807 | static void vti6_netlink_parms(struct nlattr *data[], |
| 808 | struct __ip6_tnl_parm *parms) |
| 809 | { |
| 810 | memset(parms, 0, sizeof(*parms)); |
| 811 | |
| 812 | if (!data) |
| 813 | return; |
| 814 | |
| 815 | if (data[IFLA_VTI_LINK]) |
| 816 | parms->link = nla_get_u32(data[IFLA_VTI_LINK]); |
| 817 | |
| 818 | if (data[IFLA_VTI_LOCAL]) |
| 819 | nla_memcpy(&parms->laddr, data[IFLA_VTI_LOCAL], |
| 820 | sizeof(struct in6_addr)); |
| 821 | |
| 822 | if (data[IFLA_VTI_REMOTE]) |
| 823 | nla_memcpy(&parms->raddr, data[IFLA_VTI_REMOTE], |
| 824 | sizeof(struct in6_addr)); |
| 825 | |
| 826 | if (data[IFLA_VTI_IKEY]) |
| 827 | parms->i_key = nla_get_be32(data[IFLA_VTI_IKEY]); |
| 828 | |
| 829 | if (data[IFLA_VTI_OKEY]) |
| 830 | parms->o_key = nla_get_be32(data[IFLA_VTI_OKEY]); |
| 831 | } |
| 832 | |
| 833 | static int vti6_newlink(struct net *src_net, struct net_device *dev, |
| 834 | struct nlattr *tb[], struct nlattr *data[]) |
| 835 | { |
| 836 | struct net *net = dev_net(dev); |
| 837 | struct ip6_tnl *nt; |
| 838 | |
| 839 | nt = netdev_priv(dev); |
| 840 | vti6_netlink_parms(data, &nt->parms); |
| 841 | |
| 842 | nt->parms.proto = IPPROTO_IPV6; |
| 843 | |
| 844 | if (vti6_locate(net, &nt->parms, 0)) |
| 845 | return -EEXIST; |
| 846 | |
| 847 | return vti6_tnl_create2(dev); |
| 848 | } |
| 849 | |
| 850 | static int vti6_changelink(struct net_device *dev, struct nlattr *tb[], |
| 851 | struct nlattr *data[]) |
| 852 | { |
| 853 | struct ip6_tnl *t; |
| 854 | struct __ip6_tnl_parm p; |
| 855 | struct net *net = dev_net(dev); |
| 856 | struct vti6_net *ip6n = net_generic(net, vti6_net_id); |
| 857 | |
| 858 | if (dev == ip6n->fb_tnl_dev) |
| 859 | return -EINVAL; |
| 860 | |
| 861 | vti6_netlink_parms(data, &p); |
| 862 | |
| 863 | t = vti6_locate(net, &p, 0); |
| 864 | |
| 865 | if (t) { |
| 866 | if (t->dev != dev) |
| 867 | return -EEXIST; |
| 868 | } else |
| 869 | t = netdev_priv(dev); |
| 870 | |
| 871 | return vti6_update(t, &p); |
| 872 | } |
| 873 | |
| 874 | static size_t vti6_get_size(const struct net_device *dev) |
| 875 | { |
| 876 | return |
| 877 | /* IFLA_VTI_LINK */ |
| 878 | nla_total_size(4) + |
| 879 | /* IFLA_VTI_LOCAL */ |
| 880 | nla_total_size(sizeof(struct in6_addr)) + |
| 881 | /* IFLA_VTI_REMOTE */ |
| 882 | nla_total_size(sizeof(struct in6_addr)) + |
| 883 | /* IFLA_VTI_IKEY */ |
| 884 | nla_total_size(4) + |
| 885 | /* IFLA_VTI_OKEY */ |
| 886 | nla_total_size(4) + |
| 887 | 0; |
| 888 | } |
| 889 | |
| 890 | static int vti6_fill_info(struct sk_buff *skb, const struct net_device *dev) |
| 891 | { |
| 892 | struct ip6_tnl *tunnel = netdev_priv(dev); |
| 893 | struct __ip6_tnl_parm *parm = &tunnel->parms; |
| 894 | |
| 895 | if (nla_put_u32(skb, IFLA_VTI_LINK, parm->link) || |
| 896 | nla_put(skb, IFLA_VTI_LOCAL, sizeof(struct in6_addr), |
| 897 | &parm->laddr) || |
| 898 | nla_put(skb, IFLA_VTI_REMOTE, sizeof(struct in6_addr), |
| 899 | &parm->raddr) || |
| 900 | nla_put_be32(skb, IFLA_VTI_IKEY, parm->i_key) || |
| 901 | nla_put_be32(skb, IFLA_VTI_OKEY, parm->o_key)) |
| 902 | goto nla_put_failure; |
| 903 | return 0; |
| 904 | |
| 905 | nla_put_failure: |
| 906 | return -EMSGSIZE; |
| 907 | } |
| 908 | |
| 909 | static const struct nla_policy vti6_policy[IFLA_VTI_MAX + 1] = { |
| 910 | [IFLA_VTI_LINK] = { .type = NLA_U32 }, |
| 911 | [IFLA_VTI_LOCAL] = { .len = sizeof(struct in6_addr) }, |
| 912 | [IFLA_VTI_REMOTE] = { .len = sizeof(struct in6_addr) }, |
| 913 | [IFLA_VTI_IKEY] = { .type = NLA_U32 }, |
| 914 | [IFLA_VTI_OKEY] = { .type = NLA_U32 }, |
| 915 | }; |
| 916 | |
| 917 | static struct rtnl_link_ops vti6_link_ops __read_mostly = { |
| 918 | .kind = "vti6", |
| 919 | .maxtype = IFLA_VTI_MAX, |
| 920 | .policy = vti6_policy, |
| 921 | .priv_size = sizeof(struct ip6_tnl), |
| 922 | .setup = vti6_dev_setup, |
| 923 | .validate = vti6_validate, |
| 924 | .newlink = vti6_newlink, |
| 925 | .changelink = vti6_changelink, |
| 926 | .get_size = vti6_get_size, |
| 927 | .fill_info = vti6_fill_info, |
| 928 | }; |
| 929 | |
| 930 | static struct xfrm_tunnel_notifier vti6_handler __read_mostly = { |
| 931 | .handler = vti6_rcv, |
| 932 | .priority = 1, |
| 933 | }; |
| 934 | |
| 935 | static void __net_exit vti6_destroy_tunnels(struct vti6_net *ip6n) |
| 936 | { |
| 937 | int h; |
| 938 | struct ip6_tnl *t; |
| 939 | LIST_HEAD(list); |
| 940 | |
| 941 | for (h = 0; h < HASH_SIZE; h++) { |
| 942 | t = rtnl_dereference(ip6n->tnls_r_l[h]); |
| 943 | while (t != NULL) { |
| 944 | unregister_netdevice_queue(t->dev, &list); |
| 945 | t = rtnl_dereference(t->next); |
| 946 | } |
| 947 | } |
| 948 | |
| 949 | t = rtnl_dereference(ip6n->tnls_wc[0]); |
| 950 | unregister_netdevice_queue(t->dev, &list); |
| 951 | unregister_netdevice_many(&list); |
| 952 | } |
| 953 | |
| 954 | static int __net_init vti6_init_net(struct net *net) |
| 955 | { |
| 956 | struct vti6_net *ip6n = net_generic(net, vti6_net_id); |
| 957 | struct ip6_tnl *t = NULL; |
| 958 | int err; |
| 959 | |
| 960 | ip6n->tnls[0] = ip6n->tnls_wc; |
| 961 | ip6n->tnls[1] = ip6n->tnls_r_l; |
| 962 | |
| 963 | err = -ENOMEM; |
| 964 | ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6_vti0", |
| 965 | vti6_dev_setup); |
| 966 | |
| 967 | if (!ip6n->fb_tnl_dev) |
| 968 | goto err_alloc_dev; |
| 969 | dev_net_set(ip6n->fb_tnl_dev, net); |
| 970 | |
| 971 | err = vti6_fb_tnl_dev_init(ip6n->fb_tnl_dev); |
| 972 | if (err < 0) |
| 973 | goto err_register; |
| 974 | |
| 975 | err = register_netdev(ip6n->fb_tnl_dev); |
| 976 | if (err < 0) |
| 977 | goto err_register; |
| 978 | |
| 979 | t = netdev_priv(ip6n->fb_tnl_dev); |
| 980 | |
| 981 | strcpy(t->parms.name, ip6n->fb_tnl_dev->name); |
| 982 | return 0; |
| 983 | |
| 984 | err_register: |
| 985 | vti6_dev_free(ip6n->fb_tnl_dev); |
| 986 | err_alloc_dev: |
| 987 | return err; |
| 988 | } |
| 989 | |
| 990 | static void __net_exit vti6_exit_net(struct net *net) |
| 991 | { |
| 992 | struct vti6_net *ip6n = net_generic(net, vti6_net_id); |
| 993 | |
| 994 | rtnl_lock(); |
| 995 | vti6_destroy_tunnels(ip6n); |
| 996 | rtnl_unlock(); |
| 997 | } |
| 998 | |
| 999 | static struct pernet_operations vti6_net_ops = { |
| 1000 | .init = vti6_init_net, |
| 1001 | .exit = vti6_exit_net, |
| 1002 | .id = &vti6_net_id, |
| 1003 | .size = sizeof(struct vti6_net), |
| 1004 | }; |
| 1005 | |
| 1006 | /** |
| 1007 | * vti6_tunnel_init - register protocol and reserve needed resources |
| 1008 | * |
| 1009 | * Return: 0 on success |
| 1010 | **/ |
| 1011 | static int __init vti6_tunnel_init(void) |
| 1012 | { |
| 1013 | int err; |
| 1014 | |
| 1015 | err = register_pernet_device(&vti6_net_ops); |
| 1016 | if (err < 0) |
| 1017 | goto out_pernet; |
| 1018 | |
| 1019 | err = xfrm6_mode_tunnel_input_register(&vti6_handler); |
| 1020 | if (err < 0) { |
| 1021 | pr_err("%s: can't register vti6\n", __func__); |
| 1022 | goto out; |
| 1023 | } |
| 1024 | err = rtnl_link_register(&vti6_link_ops); |
| 1025 | if (err < 0) |
| 1026 | goto rtnl_link_failed; |
| 1027 | |
| 1028 | return 0; |
| 1029 | |
| 1030 | rtnl_link_failed: |
| 1031 | xfrm6_mode_tunnel_input_deregister(&vti6_handler); |
| 1032 | out: |
| 1033 | unregister_pernet_device(&vti6_net_ops); |
| 1034 | out_pernet: |
| 1035 | return err; |
| 1036 | } |
| 1037 | |
| 1038 | /** |
| 1039 | * vti6_tunnel_cleanup - free resources and unregister protocol |
| 1040 | **/ |
| 1041 | static void __exit vti6_tunnel_cleanup(void) |
| 1042 | { |
| 1043 | rtnl_link_unregister(&vti6_link_ops); |
| 1044 | if (xfrm6_mode_tunnel_input_deregister(&vti6_handler)) |
| 1045 | pr_info("%s: can't deregister vti6\n", __func__); |
| 1046 | |
| 1047 | unregister_pernet_device(&vti6_net_ops); |
| 1048 | } |
| 1049 | |
| 1050 | module_init(vti6_tunnel_init); |
| 1051 | module_exit(vti6_tunnel_cleanup); |
| 1052 | MODULE_LICENSE("GPL"); |
| 1053 | MODULE_ALIAS_RTNL_LINK("vti6"); |
| 1054 | MODULE_ALIAS_NETDEV("ip6_vti0"); |
| 1055 | MODULE_AUTHOR("Steffen Klassert"); |
| 1056 | MODULE_DESCRIPTION("IPv6 virtual tunnel interface"); |