1 /* 2 * NET3 IP device support routines. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License 6 * as published by the Free Software Foundation; either version 7 * 2 of the License, or (at your option) any later version. 8 * 9 * Derived from the IP parts of dev.c 1.0.19 10 * Authors: Ross Biro 11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> 12 * Mark Evans, <evansmp@uhura.aston.ac.uk> 13 * 14 * Additional Authors: 15 * Alan Cox, <gw4pts@gw4pts.ampr.org> 16 * Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> 17 * 18 * Changes: 19 * Alexey Kuznetsov: pa_* fields are replaced with ifaddr 20 * lists. 21 * Cyrus Durgin: updated for kmod 22 * Matthias Andree: in devinet_ioctl, compare label and 23 * address (4.4BSD alias style support), 24 * fall back to comparing just the label 25 * if no match found. 26 */ 27 28 29 #include <asm/uaccess.h> 30 #include <asm/system.h> 31 #include <linux/bitops.h> 32 #include <linux/capability.h> 33 #include <linux/module.h> 34 #include <linux/types.h> 35 #include <linux/kernel.h> 36 #include <linux/string.h> 37 #include <linux/mm.h> 38 #include <linux/socket.h> 39 #include <linux/sockios.h> 40 #include <linux/in.h> 41 #include <linux/errno.h> 42 #include <linux/interrupt.h> 43 #include <linux/if_addr.h> 44 #include <linux/if_ether.h> 45 #include <linux/inet.h> 46 #include <linux/netdevice.h> 47 #include <linux/etherdevice.h> 48 #include <linux/skbuff.h> 49 #include <linux/init.h> 50 #include <linux/notifier.h> 51 #include <linux/inetdevice.h> 52 #include <linux/igmp.h> 53 #include <linux/slab.h> 54 #ifdef CONFIG_SYSCTL 55 #include <linux/sysctl.h> 56 #endif 57 #include <linux/kmod.h> 58 59 #include <net/arp.h> 60 #include <net/ip.h> 61 #include <net/route.h> 62 #include <net/ip_fib.h> 63 #include <net/rtnetlink.h> 64 #include <net/net_namespace.h> 65 66 static struct ipv4_devconf ipv4_devconf = { 67 .data = { 68 [IPV4_DEVCONF_ACCEPT_REDIRECTS - 1] = 1, 69 [IPV4_DEVCONF_SEND_REDIRECTS - 1] = 1, 70 [IPV4_DEVCONF_SECURE_REDIRECTS - 1] = 1, 71 [IPV4_DEVCONF_SHARED_MEDIA - 1] = 1, 72 }, 73 }; 74 75 static struct ipv4_devconf ipv4_devconf_dflt = { 76 .data = { 77 [IPV4_DEVCONF_ACCEPT_REDIRECTS - 1] = 1, 78 [IPV4_DEVCONF_SEND_REDIRECTS - 1] = 1, 79 [IPV4_DEVCONF_SECURE_REDIRECTS - 1] = 1, 80 [IPV4_DEVCONF_SHARED_MEDIA - 1] = 1, 81 [IPV4_DEVCONF_ACCEPT_SOURCE_ROUTE - 1] = 1, 82 }, 83 }; 84 85 #define IPV4_DEVCONF_DFLT(net, attr) \ 86 IPV4_DEVCONF((*net->ipv4.devconf_dflt), attr) 87 88 static const struct nla_policy ifa_ipv4_policy[IFA_MAX+1] = { 89 [IFA_LOCAL] = { .type = NLA_U32 }, 90 [IFA_ADDRESS] = { .type = NLA_U32 }, 91 [IFA_BROADCAST] = { .type = NLA_U32 }, 92 [IFA_LABEL] = { .type = NLA_STRING, .len = IFNAMSIZ - 1 }, 93 }; 94 95 static void rtmsg_ifa(int event, struct in_ifaddr *, struct nlmsghdr *, u32); 96 97 static BLOCKING_NOTIFIER_HEAD(inetaddr_chain); 98 static void inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap, 99 int destroy); 100 #ifdef CONFIG_SYSCTL 101 static void devinet_sysctl_register(struct in_device *idev); 102 static void devinet_sysctl_unregister(struct in_device *idev); 103 #else 104 static inline void devinet_sysctl_register(struct in_device *idev) 105 { 106 } 107 static inline void devinet_sysctl_unregister(struct in_device *idev) 108 { 109 } 110 #endif 111 112 /* Locks all the inet devices. */ 113 114 static struct in_ifaddr *inet_alloc_ifa(void) 115 { 116 return kzalloc(sizeof(struct in_ifaddr), GFP_KERNEL); 117 } 118 119 static void inet_rcu_free_ifa(struct rcu_head *head) 120 { 121 struct in_ifaddr *ifa = container_of(head, struct in_ifaddr, rcu_head); 122 if (ifa->ifa_dev) 123 in_dev_put(ifa->ifa_dev); 124 kfree(ifa); 125 } 126 127 static inline void inet_free_ifa(struct in_ifaddr *ifa) 128 { 129 call_rcu(&ifa->rcu_head, inet_rcu_free_ifa); 130 } 131 132 void in_dev_finish_destroy(struct in_device *idev) 133 { 134 struct net_device *dev = idev->dev; 135 136 WARN_ON(idev->ifa_list); 137 WARN_ON(idev->mc_list); 138 #ifdef NET_REFCNT_DEBUG 139 printk(KERN_DEBUG "in_dev_finish_destroy: %p=%s\n", 140 idev, dev ? dev->name : "NIL"); 141 #endif 142 dev_put(dev); 143 if (!idev->dead) 144 pr_err("Freeing alive in_device %p\n", idev); 145 else 146 kfree(idev); 147 } 148 EXPORT_SYMBOL(in_dev_finish_destroy); 149 150 static struct in_device *inetdev_init(struct net_device *dev) 151 { 152 struct in_device *in_dev; 153 154 ASSERT_RTNL(); 155 156 in_dev = kzalloc(sizeof(*in_dev), GFP_KERNEL); 157 if (!in_dev) 158 goto out; 159 memcpy(&in_dev->cnf, dev_net(dev)->ipv4.devconf_dflt, 160 sizeof(in_dev->cnf)); 161 in_dev->cnf.sysctl = NULL; 162 in_dev->dev = dev; 163 in_dev->arp_parms = neigh_parms_alloc(dev, &arp_tbl); 164 if (!in_dev->arp_parms) 165 goto out_kfree; 166 if (IPV4_DEVCONF(in_dev->cnf, FORWARDING)) 167 dev_disable_lro(dev); 168 /* Reference in_dev->dev */ 169 dev_hold(dev); 170 /* Account for reference dev->ip_ptr (below) */ 171 in_dev_hold(in_dev); 172 173 devinet_sysctl_register(in_dev); 174 ip_mc_init_dev(in_dev); 175 if (dev->flags & IFF_UP) 176 ip_mc_up(in_dev); 177 178 /* we can receive as soon as ip_ptr is set -- do this last */ 179 rcu_assign_pointer(dev->ip_ptr, in_dev); 180 out: 181 return in_dev; 182 out_kfree: 183 kfree(in_dev); 184 in_dev = NULL; 185 goto out; 186 } 187 188 static void in_dev_rcu_put(struct rcu_head *head) 189 { 190 struct in_device *idev = container_of(head, struct in_device, rcu_head); 191 in_dev_put(idev); 192 } 193 194 static void inetdev_destroy(struct in_device *in_dev) 195 { 196 struct in_ifaddr *ifa; 197 struct net_device *dev; 198 199 ASSERT_RTNL(); 200 201 dev = in_dev->dev; 202 203 in_dev->dead = 1; 204 205 ip_mc_destroy_dev(in_dev); 206 207 while ((ifa = in_dev->ifa_list) != NULL) { 208 inet_del_ifa(in_dev, &in_dev->ifa_list, 0); 209 inet_free_ifa(ifa); 210 } 211 212 rcu_assign_pointer(dev->ip_ptr, NULL); 213 214 devinet_sysctl_unregister(in_dev); 215 neigh_parms_release(&arp_tbl, in_dev->arp_parms); 216 arp_ifdown(dev); 217 218 call_rcu(&in_dev->rcu_head, in_dev_rcu_put); 219 } 220 221 int inet_addr_onlink(struct in_device *in_dev, __be32 a, __be32 b) 222 { 223 rcu_read_lock(); 224 for_primary_ifa(in_dev) { 225 if (inet_ifa_match(a, ifa)) { 226 if (!b || inet_ifa_match(b, ifa)) { 227 rcu_read_unlock(); 228 return 1; 229 } 230 } 231 } endfor_ifa(in_dev); 232 rcu_read_unlock(); 233 return 0; 234 } 235 236 static void __inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap, 237 int destroy, struct nlmsghdr *nlh, u32 pid) 238 { 239 struct in_ifaddr *promote = NULL; 240 struct in_ifaddr *ifa, *ifa1 = *ifap; 241 struct in_ifaddr *last_prim = in_dev->ifa_list; 242 struct in_ifaddr *prev_prom = NULL; 243 int do_promote = IN_DEV_PROMOTE_SECONDARIES(in_dev); 244 245 ASSERT_RTNL(); 246 247 /* 1. Deleting primary ifaddr forces deletion all secondaries 248 * unless alias promotion is set 249 **/ 250 251 if (!(ifa1->ifa_flags & IFA_F_SECONDARY)) { 252 struct in_ifaddr **ifap1 = &ifa1->ifa_next; 253 254 while ((ifa = *ifap1) != NULL) { 255 if (!(ifa->ifa_flags & IFA_F_SECONDARY) && 256 ifa1->ifa_scope <= ifa->ifa_scope) 257 last_prim = ifa; 258 259 if (!(ifa->ifa_flags & IFA_F_SECONDARY) || 260 ifa1->ifa_mask != ifa->ifa_mask || 261 !inet_ifa_match(ifa1->ifa_address, ifa)) { 262 ifap1 = &ifa->ifa_next; 263 prev_prom = ifa; 264 continue; 265 } 266 267 if (!do_promote) { 268 *ifap1 = ifa->ifa_next; 269 270 rtmsg_ifa(RTM_DELADDR, ifa, nlh, pid); 271 blocking_notifier_call_chain(&inetaddr_chain, 272 NETDEV_DOWN, ifa); 273 inet_free_ifa(ifa); 274 } else { 275 promote = ifa; 276 break; 277 } 278 } 279 } 280 281 /* 2. Unlink it */ 282 283 *ifap = ifa1->ifa_next; 284 285 /* 3. Announce address deletion */ 286 287 /* Send message first, then call notifier. 288 At first sight, FIB update triggered by notifier 289 will refer to already deleted ifaddr, that could confuse 290 netlink listeners. It is not true: look, gated sees 291 that route deleted and if it still thinks that ifaddr 292 is valid, it will try to restore deleted routes... Grr. 293 So that, this order is correct. 294 */ 295 rtmsg_ifa(RTM_DELADDR, ifa1, nlh, pid); 296 blocking_notifier_call_chain(&inetaddr_chain, NETDEV_DOWN, ifa1); 297 298 if (promote) { 299 300 if (prev_prom) { 301 prev_prom->ifa_next = promote->ifa_next; 302 promote->ifa_next = last_prim->ifa_next; 303 last_prim->ifa_next = promote; 304 } 305 306 promote->ifa_flags &= ~IFA_F_SECONDARY; 307 rtmsg_ifa(RTM_NEWADDR, promote, nlh, pid); 308 blocking_notifier_call_chain(&inetaddr_chain, 309 NETDEV_UP, promote); 310 for (ifa = promote->ifa_next; ifa; ifa = ifa->ifa_next) { 311 if (ifa1->ifa_mask != ifa->ifa_mask || 312 !inet_ifa_match(ifa1->ifa_address, ifa)) 313 continue; 314 fib_add_ifaddr(ifa); 315 } 316 317 } 318 if (destroy) 319 inet_free_ifa(ifa1); 320 } 321 322 static void inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap, 323 int destroy) 324 { 325 __inet_del_ifa(in_dev, ifap, destroy, NULL, 0); 326 } 327 328 static int __inet_insert_ifa(struct in_ifaddr *ifa, struct nlmsghdr *nlh, 329 u32 pid) 330 { 331 struct in_device *in_dev = ifa->ifa_dev; 332 struct in_ifaddr *ifa1, **ifap, **last_primary; 333 334 ASSERT_RTNL(); 335 336 if (!ifa->ifa_local) { 337 inet_free_ifa(ifa); 338 return 0; 339 } 340 341 ifa->ifa_flags &= ~IFA_F_SECONDARY; 342 last_primary = &in_dev->ifa_list; 343 344 for (ifap = &in_dev->ifa_list; (ifa1 = *ifap) != NULL; 345 ifap = &ifa1->ifa_next) { 346 if (!(ifa1->ifa_flags & IFA_F_SECONDARY) && 347 ifa->ifa_scope <= ifa1->ifa_scope) 348 last_primary = &ifa1->ifa_next; 349 if (ifa1->ifa_mask == ifa->ifa_mask && 350 inet_ifa_match(ifa1->ifa_address, ifa)) { 351 if (ifa1->ifa_local == ifa->ifa_local) { 352 inet_free_ifa(ifa); 353 return -EEXIST; 354 } 355 if (ifa1->ifa_scope != ifa->ifa_scope) { 356 inet_free_ifa(ifa); 357 return -EINVAL; 358 } 359 ifa->ifa_flags |= IFA_F_SECONDARY; 360 } 361 } 362 363 if (!(ifa->ifa_flags & IFA_F_SECONDARY)) { 364 net_srandom(ifa->ifa_local); 365 ifap = last_primary; 366 } 367 368 ifa->ifa_next = *ifap; 369 *ifap = ifa; 370 371 /* Send message first, then call notifier. 372 Notifier will trigger FIB update, so that 373 listeners of netlink will know about new ifaddr */ 374 rtmsg_ifa(RTM_NEWADDR, ifa, nlh, pid); 375 blocking_notifier_call_chain(&inetaddr_chain, NETDEV_UP, ifa); 376 377 return 0; 378 } 379 380 static int inet_insert_ifa(struct in_ifaddr *ifa) 381 { 382 return __inet_insert_ifa(ifa, NULL, 0); 383 } 384 385 static int inet_set_ifa(struct net_device *dev, struct in_ifaddr *ifa) 386 { 387 struct in_device *in_dev = __in_dev_get_rtnl(dev); 388 389 ASSERT_RTNL(); 390 391 if (!in_dev) { 392 inet_free_ifa(ifa); 393 return -ENOBUFS; 394 } 395 ipv4_devconf_setall(in_dev); 396 if (ifa->ifa_dev != in_dev) { 397 WARN_ON(ifa->ifa_dev); 398 in_dev_hold(in_dev); 399 ifa->ifa_dev = in_dev; 400 } 401 if (ipv4_is_loopback(ifa->ifa_local)) 402 ifa->ifa_scope = RT_SCOPE_HOST; 403 return inet_insert_ifa(ifa); 404 } 405 406 /* Caller must hold RCU or RTNL : 407 * We dont take a reference on found in_device 408 */ 409 struct in_device *inetdev_by_index(struct net *net, int ifindex) 410 { 411 struct net_device *dev; 412 struct in_device *in_dev = NULL; 413 414 rcu_read_lock(); 415 dev = dev_get_by_index_rcu(net, ifindex); 416 if (dev) 417 in_dev = rcu_dereference_rtnl(dev->ip_ptr); 418 rcu_read_unlock(); 419 return in_dev; 420 } 421 EXPORT_SYMBOL(inetdev_by_index); 422 423 /* Called only from RTNL semaphored context. No locks. */ 424 425 struct in_ifaddr *inet_ifa_byprefix(struct in_device *in_dev, __be32 prefix, 426 __be32 mask) 427 { 428 ASSERT_RTNL(); 429 430 for_primary_ifa(in_dev) { 431 if (ifa->ifa_mask == mask && inet_ifa_match(prefix, ifa)) 432 return ifa; 433 } endfor_ifa(in_dev); 434 return NULL; 435 } 436 437 static int inet_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg) 438 { 439 struct net *net = sock_net(skb->sk); 440 struct nlattr *tb[IFA_MAX+1]; 441 struct in_device *in_dev; 442 struct ifaddrmsg *ifm; 443 struct in_ifaddr *ifa, **ifap; 444 int err = -EINVAL; 445 446 ASSERT_RTNL(); 447 448 err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv4_policy); 449 if (err < 0) 450 goto errout; 451 452 ifm = nlmsg_data(nlh); 453 in_dev = inetdev_by_index(net, ifm->ifa_index); 454 if (in_dev == NULL) { 455 err = -ENODEV; 456 goto errout; 457 } 458 459 for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL; 460 ifap = &ifa->ifa_next) { 461 if (tb[IFA_LOCAL] && 462 ifa->ifa_local != nla_get_be32(tb[IFA_LOCAL])) 463 continue; 464 465 if (tb[IFA_LABEL] && nla_strcmp(tb[IFA_LABEL], ifa->ifa_label)) 466 continue; 467 468 if (tb[IFA_ADDRESS] && 469 (ifm->ifa_prefixlen != ifa->ifa_prefixlen || 470 !inet_ifa_match(nla_get_be32(tb[IFA_ADDRESS]), ifa))) 471 continue; 472 473 __inet_del_ifa(in_dev, ifap, 1, nlh, NETLINK_CB(skb).pid); 474 return 0; 475 } 476 477 err = -EADDRNOTAVAIL; 478 errout: 479 return err; 480 } 481 482 static struct in_ifaddr *rtm_to_ifaddr(struct net *net, struct nlmsghdr *nlh) 483 { 484 struct nlattr *tb[IFA_MAX+1]; 485 struct in_ifaddr *ifa; 486 struct ifaddrmsg *ifm; 487 struct net_device *dev; 488 struct in_device *in_dev; 489 int err; 490 491 err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv4_policy); 492 if (err < 0) 493 goto errout; 494 495 ifm = nlmsg_data(nlh); 496 err = -EINVAL; 497 if (ifm->ifa_prefixlen > 32 || tb[IFA_LOCAL] == NULL) 498 goto errout; 499 500 dev = __dev_get_by_index(net, ifm->ifa_index); 501 err = -ENODEV; 502 if (dev == NULL) 503 goto errout; 504 505 in_dev = __in_dev_get_rtnl(dev); 506 err = -ENOBUFS; 507 if (in_dev == NULL) 508 goto errout; 509 510 ifa = inet_alloc_ifa(); 511 if (ifa == NULL) 512 /* 513 * A potential indev allocation can be left alive, it stays 514 * assigned to its device and is destroy with it. 515 */ 516 goto errout; 517 518 ipv4_devconf_setall(in_dev); 519 in_dev_hold(in_dev); 520 521 if (tb[IFA_ADDRESS] == NULL) 522 tb[IFA_ADDRESS] = tb[IFA_LOCAL]; 523 524 ifa->ifa_prefixlen = ifm->ifa_prefixlen; 525 ifa->ifa_mask = inet_make_mask(ifm->ifa_prefixlen); 526 ifa->ifa_flags = ifm->ifa_flags; 527 ifa->ifa_scope = ifm->ifa_scope; 528 ifa->ifa_dev = in_dev; 529 530 ifa->ifa_local = nla_get_be32(tb[IFA_LOCAL]); 531 ifa->ifa_address = nla_get_be32(tb[IFA_ADDRESS]); 532 533 if (tb[IFA_BROADCAST]) 534 ifa->ifa_broadcast = nla_get_be32(tb[IFA_BROADCAST]); 535 536 if (tb[IFA_LABEL]) 537 nla_strlcpy(ifa->ifa_label, tb[IFA_LABEL], IFNAMSIZ); 538 else 539 memcpy(ifa->ifa_label, dev->name, IFNAMSIZ); 540 541 return ifa; 542 543 errout: 544 return ERR_PTR(err); 545 } 546 547 static int inet_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg) 548 { 549 struct net *net = sock_net(skb->sk); 550 struct in_ifaddr *ifa; 551 552 ASSERT_RTNL(); 553 554 ifa = rtm_to_ifaddr(net, nlh); 555 if (IS_ERR(ifa)) 556 return PTR_ERR(ifa); 557 558 return __inet_insert_ifa(ifa, nlh, NETLINK_CB(skb).pid); 559 } 560 561 /* 562 * Determine a default network mask, based on the IP address. 563 */ 564 565 static inline int inet_abc_len(__be32 addr) 566 { 567 int rc = -1; /* Something else, probably a multicast. */ 568 569 if (ipv4_is_zeronet(addr)) 570 rc = 0; 571 else { 572 __u32 haddr = ntohl(addr); 573 574 if (IN_CLASSA(haddr)) 575 rc = 8; 576 else if (IN_CLASSB(haddr)) 577 rc = 16; 578 else if (IN_CLASSC(haddr)) 579 rc = 24; 580 } 581 582 return rc; 583 } 584 585 586 int devinet_ioctl(struct net *net, unsigned int cmd, void __user *arg) 587 { 588 struct ifreq ifr; 589 struct sockaddr_in sin_orig; 590 struct sockaddr_in *sin = (struct sockaddr_in *)&ifr.ifr_addr; 591 struct in_device *in_dev; 592 struct in_ifaddr **ifap = NULL; 593 struct in_ifaddr *ifa = NULL; 594 struct net_device *dev; 595 char *colon; 596 int ret = -EFAULT; 597 int tryaddrmatch = 0; 598 599 /* 600 * Fetch the caller's info block into kernel space 601 */ 602 603 if (copy_from_user(&ifr, arg, sizeof(struct ifreq))) 604 goto out; 605 ifr.ifr_name[IFNAMSIZ - 1] = 0; 606 607 /* save original address for comparison */ 608 memcpy(&sin_orig, sin, sizeof(*sin)); 609 610 colon = strchr(ifr.ifr_name, ':'); 611 if (colon) 612 *colon = 0; 613 614 dev_load(net, ifr.ifr_name); 615 616 switch (cmd) { 617 case SIOCGIFADDR: /* Get interface address */ 618 case SIOCGIFBRDADDR: /* Get the broadcast address */ 619 case SIOCGIFDSTADDR: /* Get the destination address */ 620 case SIOCGIFNETMASK: /* Get the netmask for the interface */ 621 /* Note that these ioctls will not sleep, 622 so that we do not impose a lock. 623 One day we will be forced to put shlock here (I mean SMP) 624 */ 625 tryaddrmatch = (sin_orig.sin_family == AF_INET); 626 memset(sin, 0, sizeof(*sin)); 627 sin->sin_family = AF_INET; 628 break; 629 630 case SIOCSIFFLAGS: 631 ret = -EACCES; 632 if (!capable(CAP_NET_ADMIN)) 633 goto out; 634 break; 635 case SIOCSIFADDR: /* Set interface address (and family) */ 636 case SIOCSIFBRDADDR: /* Set the broadcast address */ 637 case SIOCSIFDSTADDR: /* Set the destination address */ 638 case SIOCSIFNETMASK: /* Set the netmask for the interface */ 639 ret = -EACCES; 640 if (!capable(CAP_NET_ADMIN)) 641 goto out; 642 ret = -EINVAL; 643 if (sin->sin_family != AF_INET) 644 goto out; 645 break; 646 default: 647 ret = -EINVAL; 648 goto out; 649 } 650 651 rtnl_lock(); 652 653 ret = -ENODEV; 654 dev = __dev_get_by_name(net, ifr.ifr_name); 655 if (!dev) 656 goto done; 657 658 if (colon) 659 *colon = ':'; 660 661 in_dev = __in_dev_get_rtnl(dev); 662 if (in_dev) { 663 if (tryaddrmatch) { 664 /* Matthias Andree */ 665 /* compare label and address (4.4BSD style) */ 666 /* note: we only do this for a limited set of ioctls 667 and only if the original address family was AF_INET. 668 This is checked above. */ 669 for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL; 670 ifap = &ifa->ifa_next) { 671 if (!strcmp(ifr.ifr_name, ifa->ifa_label) && 672 sin_orig.sin_addr.s_addr == 673 ifa->ifa_address) { 674 break; /* found */ 675 } 676 } 677 } 678 /* we didn't get a match, maybe the application is 679 4.3BSD-style and passed in junk so we fall back to 680 comparing just the label */ 681 if (!ifa) { 682 for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL; 683 ifap = &ifa->ifa_next) 684 if (!strcmp(ifr.ifr_name, ifa->ifa_label)) 685 break; 686 } 687 } 688 689 ret = -EADDRNOTAVAIL; 690 if (!ifa && cmd != SIOCSIFADDR && cmd != SIOCSIFFLAGS) 691 goto done; 692 693 switch (cmd) { 694 case SIOCGIFADDR: /* Get interface address */ 695 sin->sin_addr.s_addr = ifa->ifa_local; 696 goto rarok; 697 698 case SIOCGIFBRDADDR: /* Get the broadcast address */ 699 sin->sin_addr.s_addr = ifa->ifa_broadcast; 700 goto rarok; 701 702 case SIOCGIFDSTADDR: /* Get the destination address */ 703 sin->sin_addr.s_addr = ifa->ifa_address; 704 goto rarok; 705 706 case SIOCGIFNETMASK: /* Get the netmask for the interface */ 707 sin->sin_addr.s_addr = ifa->ifa_mask; 708 goto rarok; 709 710 case SIOCSIFFLAGS: 711 if (colon) { 712 ret = -EADDRNOTAVAIL; 713 if (!ifa) 714 break; 715 ret = 0; 716 if (!(ifr.ifr_flags & IFF_UP)) 717 inet_del_ifa(in_dev, ifap, 1); 718 break; 719 } 720 ret = dev_change_flags(dev, ifr.ifr_flags); 721 break; 722 723 case SIOCSIFADDR: /* Set interface address (and family) */ 724 ret = -EINVAL; 725 if (inet_abc_len(sin->sin_addr.s_addr) < 0) 726 break; 727 728 if (!ifa) { 729 ret = -ENOBUFS; 730 ifa = inet_alloc_ifa(); 731 if (!ifa) 732 break; 733 if (colon) 734 memcpy(ifa->ifa_label, ifr.ifr_name, IFNAMSIZ); 735 else 736 memcpy(ifa->ifa_label, dev->name, IFNAMSIZ); 737 } else { 738 ret = 0; 739 if (ifa->ifa_local == sin->sin_addr.s_addr) 740 break; 741 inet_del_ifa(in_dev, ifap, 0); 742 ifa->ifa_broadcast = 0; 743 ifa->ifa_scope = 0; 744 } 745 746 ifa->ifa_address = ifa->ifa_local = sin->sin_addr.s_addr; 747 748 if (!(dev->flags & IFF_POINTOPOINT)) { 749 ifa->ifa_prefixlen = inet_abc_len(ifa->ifa_address); 750 ifa->ifa_mask = inet_make_mask(ifa->ifa_prefixlen); 751 if ((dev->flags & IFF_BROADCAST) && 752 ifa->ifa_prefixlen < 31) 753 ifa->ifa_broadcast = ifa->ifa_address | 754 ~ifa->ifa_mask; 755 } else { 756 ifa->ifa_prefixlen = 32; 757 ifa->ifa_mask = inet_make_mask(32); 758 } 759 ret = inet_set_ifa(dev, ifa); 760 break; 761 762 case SIOCSIFBRDADDR: /* Set the broadcast address */ 763 ret = 0; 764 if (ifa->ifa_broadcast != sin->sin_addr.s_addr) { 765 inet_del_ifa(in_dev, ifap, 0); 766 ifa->ifa_broadcast = sin->sin_addr.s_addr; 767 inet_insert_ifa(ifa); 768 } 769 break; 770 771 case SIOCSIFDSTADDR: /* Set the destination address */ 772 ret = 0; 773 if (ifa->ifa_address == sin->sin_addr.s_addr) 774 break; 775 ret = -EINVAL; 776 if (inet_abc_len(sin->sin_addr.s_addr) < 0) 777 break; 778 ret = 0; 779 inet_del_ifa(in_dev, ifap, 0); 780 ifa->ifa_address = sin->sin_addr.s_addr; 781 inet_insert_ifa(ifa); 782 break; 783 784 case SIOCSIFNETMASK: /* Set the netmask for the interface */ 785 786 /* 787 * The mask we set must be legal. 788 */ 789 ret = -EINVAL; 790 if (bad_mask(sin->sin_addr.s_addr, 0)) 791 break; 792 ret = 0; 793 if (ifa->ifa_mask != sin->sin_addr.s_addr) { 794 __be32 old_mask = ifa->ifa_mask; 795 inet_del_ifa(in_dev, ifap, 0); 796 ifa->ifa_mask = sin->sin_addr.s_addr; 797 ifa->ifa_prefixlen = inet_mask_len(ifa->ifa_mask); 798 799 /* See if current broadcast address matches 800 * with current netmask, then recalculate 801 * the broadcast address. Otherwise it's a 802 * funny address, so don't touch it since 803 * the user seems to know what (s)he's doing... 804 */ 805 if ((dev->flags & IFF_BROADCAST) && 806 (ifa->ifa_prefixlen < 31) && 807 (ifa->ifa_broadcast == 808 (ifa->ifa_local|~old_mask))) { 809 ifa->ifa_broadcast = (ifa->ifa_local | 810 ~sin->sin_addr.s_addr); 811 } 812 inet_insert_ifa(ifa); 813 } 814 break; 815 } 816 done: 817 rtnl_unlock(); 818 out: 819 return ret; 820 rarok: 821 rtnl_unlock(); 822 ret = copy_to_user(arg, &ifr, sizeof(struct ifreq)) ? -EFAULT : 0; 823 goto out; 824 } 825 826 static int inet_gifconf(struct net_device *dev, char __user *buf, int len) 827 { 828 struct in_device *in_dev = __in_dev_get_rtnl(dev); 829 struct in_ifaddr *ifa; 830 struct ifreq ifr; 831 int done = 0; 832 833 if (!in_dev) 834 goto out; 835 836 for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) { 837 if (!buf) { 838 done += sizeof(ifr); 839 continue; 840 } 841 if (len < (int) sizeof(ifr)) 842 break; 843 memset(&ifr, 0, sizeof(struct ifreq)); 844 if (ifa->ifa_label) 845 strcpy(ifr.ifr_name, ifa->ifa_label); 846 else 847 strcpy(ifr.ifr_name, dev->name); 848 849 (*(struct sockaddr_in *)&ifr.ifr_addr).sin_family = AF_INET; 850 (*(struct sockaddr_in *)&ifr.ifr_addr).sin_addr.s_addr = 851 ifa->ifa_local; 852 853 if (copy_to_user(buf, &ifr, sizeof(struct ifreq))) { 854 done = -EFAULT; 855 break; 856 } 857 buf += sizeof(struct ifreq); 858 len -= sizeof(struct ifreq); 859 done += sizeof(struct ifreq); 860 } 861 out: 862 return done; 863 } 864 865 __be32 inet_select_addr(const struct net_device *dev, __be32 dst, int scope) 866 { 867 __be32 addr = 0; 868 struct in_device *in_dev; 869 struct net *net = dev_net(dev); 870 871 rcu_read_lock(); 872 in_dev = __in_dev_get_rcu(dev); 873 if (!in_dev) 874 goto no_in_dev; 875 876 for_primary_ifa(in_dev) { 877 if (ifa->ifa_scope > scope) 878 continue; 879 if (!dst || inet_ifa_match(dst, ifa)) { 880 addr = ifa->ifa_local; 881 break; 882 } 883 if (!addr) 884 addr = ifa->ifa_local; 885 } endfor_ifa(in_dev); 886 887 if (addr) 888 goto out_unlock; 889 no_in_dev: 890 891 /* Not loopback addresses on loopback should be preferred 892 in this case. It is importnat that lo is the first interface 893 in dev_base list. 894 */ 895 for_each_netdev_rcu(net, dev) { 896 in_dev = __in_dev_get_rcu(dev); 897 if (!in_dev) 898 continue; 899 900 for_primary_ifa(in_dev) { 901 if (ifa->ifa_scope != RT_SCOPE_LINK && 902 ifa->ifa_scope <= scope) { 903 addr = ifa->ifa_local; 904 goto out_unlock; 905 } 906 } endfor_ifa(in_dev); 907 } 908 out_unlock: 909 rcu_read_unlock(); 910 return addr; 911 } 912 EXPORT_SYMBOL(inet_select_addr); 913 914 static __be32 confirm_addr_indev(struct in_device *in_dev, __be32 dst, 915 __be32 local, int scope) 916 { 917 int same = 0; 918 __be32 addr = 0; 919 920 for_ifa(in_dev) { 921 if (!addr && 922 (local == ifa->ifa_local || !local) && 923 ifa->ifa_scope <= scope) { 924 addr = ifa->ifa_local; 925 if (same) 926 break; 927 } 928 if (!same) { 929 same = (!local || inet_ifa_match(local, ifa)) && 930 (!dst || inet_ifa_match(dst, ifa)); 931 if (same && addr) { 932 if (local || !dst) 933 break; 934 /* Is the selected addr into dst subnet? */ 935 if (inet_ifa_match(addr, ifa)) 936 break; 937 /* No, then can we use new local src? */ 938 if (ifa->ifa_scope <= scope) { 939 addr = ifa->ifa_local; 940 break; 941 } 942 /* search for large dst subnet for addr */ 943 same = 0; 944 } 945 } 946 } endfor_ifa(in_dev); 947 948 return same ? addr : 0; 949 } 950 951 /* 952 * Confirm that local IP address exists using wildcards: 953 * - in_dev: only on this interface, 0=any interface 954 * - dst: only in the same subnet as dst, 0=any dst 955 * - local: address, 0=autoselect the local address 956 * - scope: maximum allowed scope value for the local address 957 */ 958 __be32 inet_confirm_addr(struct in_device *in_dev, 959 __be32 dst, __be32 local, int scope) 960 { 961 __be32 addr = 0; 962 struct net_device *dev; 963 struct net *net; 964 965 if (scope != RT_SCOPE_LINK) 966 return confirm_addr_indev(in_dev, dst, local, scope); 967 968 net = dev_net(in_dev->dev); 969 rcu_read_lock(); 970 for_each_netdev_rcu(net, dev) { 971 in_dev = __in_dev_get_rcu(dev); 972 if (in_dev) { 973 addr = confirm_addr_indev(in_dev, dst, local, scope); 974 if (addr) 975 break; 976 } 977 } 978 rcu_read_unlock(); 979 980 return addr; 981 } 982 983 /* 984 * Device notifier 985 */ 986 987 int register_inetaddr_notifier(struct notifier_block *nb) 988 { 989 return blocking_notifier_chain_register(&inetaddr_chain, nb); 990 } 991 EXPORT_SYMBOL(register_inetaddr_notifier); 992 993 int unregister_inetaddr_notifier(struct notifier_block *nb) 994 { 995 return blocking_notifier_chain_unregister(&inetaddr_chain, nb); 996 } 997 EXPORT_SYMBOL(unregister_inetaddr_notifier); 998 999 /* Rename ifa_labels for a device name change. Make some effort to preserve 1000 * existing alias numbering and to create unique labels if possible. 1001 */ 1002 static void inetdev_changename(struct net_device *dev, struct in_device *in_dev) 1003 { 1004 struct in_ifaddr *ifa; 1005 int named = 0; 1006 1007 for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) { 1008 char old[IFNAMSIZ], *dot; 1009 1010 memcpy(old, ifa->ifa_label, IFNAMSIZ); 1011 memcpy(ifa->ifa_label, dev->name, IFNAMSIZ); 1012 if (named++ == 0) 1013 goto skip; 1014 dot = strchr(old, ':'); 1015 if (dot == NULL) { 1016 sprintf(old, ":%d", named); 1017 dot = old; 1018 } 1019 if (strlen(dot) + strlen(dev->name) < IFNAMSIZ) 1020 strcat(ifa->ifa_label, dot); 1021 else 1022 strcpy(ifa->ifa_label + (IFNAMSIZ - strlen(dot) - 1), dot); 1023 skip: 1024 rtmsg_ifa(RTM_NEWADDR, ifa, NULL, 0); 1025 } 1026 } 1027 1028 static inline bool inetdev_valid_mtu(unsigned mtu) 1029 { 1030 return mtu >= 68; 1031 } 1032 1033 /* Called only under RTNL semaphore */ 1034 1035 static int inetdev_event(struct notifier_block *this, unsigned long event, 1036 void *ptr) 1037 { 1038 struct net_device *dev = ptr; 1039 struct in_device *in_dev = __in_dev_get_rtnl(dev); 1040 1041 ASSERT_RTNL(); 1042 1043 if (!in_dev) { 1044 if (event == NETDEV_REGISTER) { 1045 in_dev = inetdev_init(dev); 1046 if (!in_dev) 1047 return notifier_from_errno(-ENOMEM); 1048 if (dev->flags & IFF_LOOPBACK) { 1049 IN_DEV_CONF_SET(in_dev, NOXFRM, 1); 1050 IN_DEV_CONF_SET(in_dev, NOPOLICY, 1); 1051 } 1052 } else if (event == NETDEV_CHANGEMTU) { 1053 /* Re-enabling IP */ 1054 if (inetdev_valid_mtu(dev->mtu)) 1055 in_dev = inetdev_init(dev); 1056 } 1057 goto out; 1058 } 1059 1060 switch (event) { 1061 case NETDEV_REGISTER: 1062 printk(KERN_DEBUG "inetdev_event: bug\n"); 1063 rcu_assign_pointer(dev->ip_ptr, NULL); 1064 break; 1065 case NETDEV_UP: 1066 if (!inetdev_valid_mtu(dev->mtu)) 1067 break; 1068 if (dev->flags & IFF_LOOPBACK) { 1069 struct in_ifaddr *ifa = inet_alloc_ifa(); 1070 1071 if (ifa) { 1072 ifa->ifa_local = 1073 ifa->ifa_address = htonl(INADDR_LOOPBACK); 1074 ifa->ifa_prefixlen = 8; 1075 ifa->ifa_mask = inet_make_mask(8); 1076 in_dev_hold(in_dev); 1077 ifa->ifa_dev = in_dev; 1078 ifa->ifa_scope = RT_SCOPE_HOST; 1079 memcpy(ifa->ifa_label, dev->name, IFNAMSIZ); 1080 inet_insert_ifa(ifa); 1081 } 1082 } 1083 ip_mc_up(in_dev); 1084 /* fall through */ 1085 case NETDEV_NOTIFY_PEERS: 1086 case NETDEV_CHANGEADDR: 1087 /* Send gratuitous ARP to notify of link change */ 1088 if (IN_DEV_ARP_NOTIFY(in_dev)) { 1089 struct in_ifaddr *ifa = in_dev->ifa_list; 1090 1091 if (ifa) 1092 arp_send(ARPOP_REQUEST, ETH_P_ARP, 1093 ifa->ifa_address, dev, 1094 ifa->ifa_address, NULL, 1095 dev->dev_addr, NULL); 1096 } 1097 break; 1098 case NETDEV_DOWN: 1099 ip_mc_down(in_dev); 1100 break; 1101 case NETDEV_PRE_TYPE_CHANGE: 1102 ip_mc_unmap(in_dev); 1103 break; 1104 case NETDEV_POST_TYPE_CHANGE: 1105 ip_mc_remap(in_dev); 1106 break; 1107 case NETDEV_CHANGEMTU: 1108 if (inetdev_valid_mtu(dev->mtu)) 1109 break; 1110 /* disable IP when MTU is not enough */ 1111 case NETDEV_UNREGISTER: 1112 inetdev_destroy(in_dev); 1113 break; 1114 case NETDEV_CHANGENAME: 1115 /* Do not notify about label change, this event is 1116 * not interesting to applications using netlink. 1117 */ 1118 inetdev_changename(dev, in_dev); 1119 1120 devinet_sysctl_unregister(in_dev); 1121 devinet_sysctl_register(in_dev); 1122 break; 1123 } 1124 out: 1125 return NOTIFY_DONE; 1126 } 1127 1128 static struct notifier_block ip_netdev_notifier = { 1129 .notifier_call = inetdev_event, 1130 }; 1131 1132 static inline size_t inet_nlmsg_size(void) 1133 { 1134 return NLMSG_ALIGN(sizeof(struct ifaddrmsg)) 1135 + nla_total_size(4) /* IFA_ADDRESS */ 1136 + nla_total_size(4) /* IFA_LOCAL */ 1137 + nla_total_size(4) /* IFA_BROADCAST */ 1138 + nla_total_size(IFNAMSIZ); /* IFA_LABEL */ 1139 } 1140 1141 static int inet_fill_ifaddr(struct sk_buff *skb, struct in_ifaddr *ifa, 1142 u32 pid, u32 seq, int event, unsigned int flags) 1143 { 1144 struct ifaddrmsg *ifm; 1145 struct nlmsghdr *nlh; 1146 1147 nlh = nlmsg_put(skb, pid, seq, event, sizeof(*ifm), flags); 1148 if (nlh == NULL) 1149 return -EMSGSIZE; 1150 1151 ifm = nlmsg_data(nlh); 1152 ifm->ifa_family = AF_INET; 1153 ifm->ifa_prefixlen = ifa->ifa_prefixlen; 1154 ifm->ifa_flags = ifa->ifa_flags|IFA_F_PERMANENT; 1155 ifm->ifa_scope = ifa->ifa_scope; 1156 ifm->ifa_index = ifa->ifa_dev->dev->ifindex; 1157 1158 if (ifa->ifa_address) 1159 NLA_PUT_BE32(skb, IFA_ADDRESS, ifa->ifa_address); 1160 1161 if (ifa->ifa_local) 1162 NLA_PUT_BE32(skb, IFA_LOCAL, ifa->ifa_local); 1163 1164 if (ifa->ifa_broadcast) 1165 NLA_PUT_BE32(skb, IFA_BROADCAST, ifa->ifa_broadcast); 1166 1167 if (ifa->ifa_label[0]) 1168 NLA_PUT_STRING(skb, IFA_LABEL, ifa->ifa_label); 1169 1170 return nlmsg_end(skb, nlh); 1171 1172 nla_put_failure: 1173 nlmsg_cancel(skb, nlh); 1174 return -EMSGSIZE; 1175 } 1176 1177 static int inet_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb) 1178 { 1179 struct net *net = sock_net(skb->sk); 1180 int h, s_h; 1181 int idx, s_idx; 1182 int ip_idx, s_ip_idx; 1183 struct net_device *dev; 1184 struct in_device *in_dev; 1185 struct in_ifaddr *ifa; 1186 struct hlist_head *head; 1187 struct hlist_node *node; 1188 1189 s_h = cb->args[0]; 1190 s_idx = idx = cb->args[1]; 1191 s_ip_idx = ip_idx = cb->args[2]; 1192 1193 for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) { 1194 idx = 0; 1195 head = &net->dev_index_head[h]; 1196 rcu_read_lock(); 1197 hlist_for_each_entry_rcu(dev, node, head, index_hlist) { 1198 if (idx < s_idx) 1199 goto cont; 1200 if (h > s_h || idx > s_idx) 1201 s_ip_idx = 0; 1202 in_dev = __in_dev_get_rcu(dev); 1203 if (!in_dev) 1204 goto cont; 1205 1206 for (ifa = in_dev->ifa_list, ip_idx = 0; ifa; 1207 ifa = ifa->ifa_next, ip_idx++) { 1208 if (ip_idx < s_ip_idx) 1209 continue; 1210 if (inet_fill_ifaddr(skb, ifa, 1211 NETLINK_CB(cb->skb).pid, 1212 cb->nlh->nlmsg_seq, 1213 RTM_NEWADDR, NLM_F_MULTI) <= 0) { 1214 rcu_read_unlock(); 1215 goto done; 1216 } 1217 } 1218 cont: 1219 idx++; 1220 } 1221 rcu_read_unlock(); 1222 } 1223 1224 done: 1225 cb->args[0] = h; 1226 cb->args[1] = idx; 1227 cb->args[2] = ip_idx; 1228 1229 return skb->len; 1230 } 1231 1232 static void rtmsg_ifa(int event, struct in_ifaddr *ifa, struct nlmsghdr *nlh, 1233 u32 pid) 1234 { 1235 struct sk_buff *skb; 1236 u32 seq = nlh ? nlh->nlmsg_seq : 0; 1237 int err = -ENOBUFS; 1238 struct net *net; 1239 1240 net = dev_net(ifa->ifa_dev->dev); 1241 skb = nlmsg_new(inet_nlmsg_size(), GFP_KERNEL); 1242 if (skb == NULL) 1243 goto errout; 1244 1245 err = inet_fill_ifaddr(skb, ifa, pid, seq, event, 0); 1246 if (err < 0) { 1247 /* -EMSGSIZE implies BUG in inet_nlmsg_size() */ 1248 WARN_ON(err == -EMSGSIZE); 1249 kfree_skb(skb); 1250 goto errout; 1251 } 1252 rtnl_notify(skb, net, pid, RTNLGRP_IPV4_IFADDR, nlh, GFP_KERNEL); 1253 return; 1254 errout: 1255 if (err < 0) 1256 rtnl_set_sk_err(net, RTNLGRP_IPV4_IFADDR, err); 1257 } 1258 1259 static size_t inet_get_link_af_size(const struct net_device *dev) 1260 { 1261 struct in_device *in_dev = __in_dev_get_rtnl(dev); 1262 1263 if (!in_dev) 1264 return 0; 1265 1266 return nla_total_size(IPV4_DEVCONF_MAX * 4); /* IFLA_INET_CONF */ 1267 } 1268 1269 static int inet_fill_link_af(struct sk_buff *skb, const struct net_device *dev) 1270 { 1271 struct in_device *in_dev = __in_dev_get_rtnl(dev); 1272 struct nlattr *nla; 1273 int i; 1274 1275 if (!in_dev) 1276 return -ENODATA; 1277 1278 nla = nla_reserve(skb, IFLA_INET_CONF, IPV4_DEVCONF_MAX * 4); 1279 if (nla == NULL) 1280 return -EMSGSIZE; 1281 1282 for (i = 0; i < IPV4_DEVCONF_MAX; i++) 1283 ((u32 *) nla_data(nla))[i] = in_dev->cnf.data[i]; 1284 1285 return 0; 1286 } 1287 1288 static const struct nla_policy inet_af_policy[IFLA_INET_MAX+1] = { 1289 [IFLA_INET_CONF] = { .type = NLA_NESTED }, 1290 }; 1291 1292 static int inet_validate_link_af(const struct net_device *dev, 1293 const struct nlattr *nla) 1294 { 1295 struct nlattr *a, *tb[IFLA_INET_MAX+1]; 1296 int err, rem; 1297 1298 if (dev && !__in_dev_get_rtnl(dev)) 1299 return -EAFNOSUPPORT; 1300 1301 err = nla_parse_nested(tb, IFLA_INET_MAX, nla, inet_af_policy); 1302 if (err < 0) 1303 return err; 1304 1305 if (tb[IFLA_INET_CONF]) { 1306 nla_for_each_nested(a, tb[IFLA_INET_CONF], rem) { 1307 int cfgid = nla_type(a); 1308 1309 if (nla_len(a) < 4) 1310 return -EINVAL; 1311 1312 if (cfgid <= 0 || cfgid > IPV4_DEVCONF_MAX) 1313 return -EINVAL; 1314 } 1315 } 1316 1317 return 0; 1318 } 1319 1320 static int inet_set_link_af(struct net_device *dev, const struct nlattr *nla) 1321 { 1322 struct in_device *in_dev = __in_dev_get_rtnl(dev); 1323 struct nlattr *a, *tb[IFLA_INET_MAX+1]; 1324 int rem; 1325 1326 if (!in_dev) 1327 return -EAFNOSUPPORT; 1328 1329 if (nla_parse_nested(tb, IFLA_INET_MAX, nla, NULL) < 0) 1330 BUG(); 1331 1332 if (tb[IFLA_INET_CONF]) { 1333 nla_for_each_nested(a, tb[IFLA_INET_CONF], rem) 1334 ipv4_devconf_set(in_dev, nla_type(a), nla_get_u32(a)); 1335 } 1336 1337 return 0; 1338 } 1339 1340 #ifdef CONFIG_SYSCTL 1341 1342 static void devinet_copy_dflt_conf(struct net *net, int i) 1343 { 1344 struct net_device *dev; 1345 1346 rcu_read_lock(); 1347 for_each_netdev_rcu(net, dev) { 1348 struct in_device *in_dev; 1349 1350 in_dev = __in_dev_get_rcu(dev); 1351 if (in_dev && !test_bit(i, in_dev->cnf.state)) 1352 in_dev->cnf.data[i] = net->ipv4.devconf_dflt->data[i]; 1353 } 1354 rcu_read_unlock(); 1355 } 1356 1357 /* called with RTNL locked */ 1358 static void inet_forward_change(struct net *net) 1359 { 1360 struct net_device *dev; 1361 int on = IPV4_DEVCONF_ALL(net, FORWARDING); 1362 1363 IPV4_DEVCONF_ALL(net, ACCEPT_REDIRECTS) = !on; 1364 IPV4_DEVCONF_DFLT(net, FORWARDING) = on; 1365 1366 for_each_netdev(net, dev) { 1367 struct in_device *in_dev; 1368 if (on) 1369 dev_disable_lro(dev); 1370 rcu_read_lock(); 1371 in_dev = __in_dev_get_rcu(dev); 1372 if (in_dev) 1373 IN_DEV_CONF_SET(in_dev, FORWARDING, on); 1374 rcu_read_unlock(); 1375 } 1376 } 1377 1378 static int devinet_conf_proc(ctl_table *ctl, int write, 1379 void __user *buffer, 1380 size_t *lenp, loff_t *ppos) 1381 { 1382 int ret = proc_dointvec(ctl, write, buffer, lenp, ppos); 1383 1384 if (write) { 1385 struct ipv4_devconf *cnf = ctl->extra1; 1386 struct net *net = ctl->extra2; 1387 int i = (int *)ctl->data - cnf->data; 1388 1389 set_bit(i, cnf->state); 1390 1391 if (cnf == net->ipv4.devconf_dflt) 1392 devinet_copy_dflt_conf(net, i); 1393 } 1394 1395 return ret; 1396 } 1397 1398 static int devinet_sysctl_forward(ctl_table *ctl, int write, 1399 void __user *buffer, 1400 size_t *lenp, loff_t *ppos) 1401 { 1402 int *valp = ctl->data; 1403 int val = *valp; 1404 loff_t pos = *ppos; 1405 int ret = proc_dointvec(ctl, write, buffer, lenp, ppos); 1406 1407 if (write && *valp != val) { 1408 struct net *net = ctl->extra2; 1409 1410 if (valp != &IPV4_DEVCONF_DFLT(net, FORWARDING)) { 1411 if (!rtnl_trylock()) { 1412 /* Restore the original values before restarting */ 1413 *valp = val; 1414 *ppos = pos; 1415 return restart_syscall(); 1416 } 1417 if (valp == &IPV4_DEVCONF_ALL(net, FORWARDING)) { 1418 inet_forward_change(net); 1419 } else if (*valp) { 1420 struct ipv4_devconf *cnf = ctl->extra1; 1421 struct in_device *idev = 1422 container_of(cnf, struct in_device, cnf); 1423 dev_disable_lro(idev->dev); 1424 } 1425 rtnl_unlock(); 1426 rt_cache_flush(net, 0); 1427 } 1428 } 1429 1430 return ret; 1431 } 1432 1433 static int ipv4_doint_and_flush(ctl_table *ctl, int write, 1434 void __user *buffer, 1435 size_t *lenp, loff_t *ppos) 1436 { 1437 int *valp = ctl->data; 1438 int val = *valp; 1439 int ret = proc_dointvec(ctl, write, buffer, lenp, ppos); 1440 struct net *net = ctl->extra2; 1441 1442 if (write && *valp != val) 1443 rt_cache_flush(net, 0); 1444 1445 return ret; 1446 } 1447 1448 #define DEVINET_SYSCTL_ENTRY(attr, name, mval, proc) \ 1449 { \ 1450 .procname = name, \ 1451 .data = ipv4_devconf.data + \ 1452 IPV4_DEVCONF_ ## attr - 1, \ 1453 .maxlen = sizeof(int), \ 1454 .mode = mval, \ 1455 .proc_handler = proc, \ 1456 .extra1 = &ipv4_devconf, \ 1457 } 1458 1459 #define DEVINET_SYSCTL_RW_ENTRY(attr, name) \ 1460 DEVINET_SYSCTL_ENTRY(attr, name, 0644, devinet_conf_proc) 1461 1462 #define DEVINET_SYSCTL_RO_ENTRY(attr, name) \ 1463 DEVINET_SYSCTL_ENTRY(attr, name, 0444, devinet_conf_proc) 1464 1465 #define DEVINET_SYSCTL_COMPLEX_ENTRY(attr, name, proc) \ 1466 DEVINET_SYSCTL_ENTRY(attr, name, 0644, proc) 1467 1468 #define DEVINET_SYSCTL_FLUSHING_ENTRY(attr, name) \ 1469 DEVINET_SYSCTL_COMPLEX_ENTRY(attr, name, ipv4_doint_and_flush) 1470 1471 static struct devinet_sysctl_table { 1472 struct ctl_table_header *sysctl_header; 1473 struct ctl_table devinet_vars[__IPV4_DEVCONF_MAX]; 1474 char *dev_name; 1475 } devinet_sysctl = { 1476 .devinet_vars = { 1477 DEVINET_SYSCTL_COMPLEX_ENTRY(FORWARDING, "forwarding", 1478 devinet_sysctl_forward), 1479 DEVINET_SYSCTL_RO_ENTRY(MC_FORWARDING, "mc_forwarding"), 1480 1481 DEVINET_SYSCTL_RW_ENTRY(ACCEPT_REDIRECTS, "accept_redirects"), 1482 DEVINET_SYSCTL_RW_ENTRY(SECURE_REDIRECTS, "secure_redirects"), 1483 DEVINET_SYSCTL_RW_ENTRY(SHARED_MEDIA, "shared_media"), 1484 DEVINET_SYSCTL_RW_ENTRY(RP_FILTER, "rp_filter"), 1485 DEVINET_SYSCTL_RW_ENTRY(SEND_REDIRECTS, "send_redirects"), 1486 DEVINET_SYSCTL_RW_ENTRY(ACCEPT_SOURCE_ROUTE, 1487 "accept_source_route"), 1488 DEVINET_SYSCTL_RW_ENTRY(ACCEPT_LOCAL, "accept_local"), 1489 DEVINET_SYSCTL_RW_ENTRY(SRC_VMARK, "src_valid_mark"), 1490 DEVINET_SYSCTL_RW_ENTRY(PROXY_ARP, "proxy_arp"), 1491 DEVINET_SYSCTL_RW_ENTRY(MEDIUM_ID, "medium_id"), 1492 DEVINET_SYSCTL_RW_ENTRY(BOOTP_RELAY, "bootp_relay"), 1493 DEVINET_SYSCTL_RW_ENTRY(LOG_MARTIANS, "log_martians"), 1494 DEVINET_SYSCTL_RW_ENTRY(TAG, "tag"), 1495 DEVINET_SYSCTL_RW_ENTRY(ARPFILTER, "arp_filter"), 1496 DEVINET_SYSCTL_RW_ENTRY(ARP_ANNOUNCE, "arp_announce"), 1497 DEVINET_SYSCTL_RW_ENTRY(ARP_IGNORE, "arp_ignore"), 1498 DEVINET_SYSCTL_RW_ENTRY(ARP_ACCEPT, "arp_accept"), 1499 DEVINET_SYSCTL_RW_ENTRY(ARP_NOTIFY, "arp_notify"), 1500 DEVINET_SYSCTL_RW_ENTRY(PROXY_ARP_PVLAN, "proxy_arp_pvlan"), 1501 1502 DEVINET_SYSCTL_FLUSHING_ENTRY(NOXFRM, "disable_xfrm"), 1503 DEVINET_SYSCTL_FLUSHING_ENTRY(NOPOLICY, "disable_policy"), 1504 DEVINET_SYSCTL_FLUSHING_ENTRY(FORCE_IGMP_VERSION, 1505 "force_igmp_version"), 1506 DEVINET_SYSCTL_FLUSHING_ENTRY(PROMOTE_SECONDARIES, 1507 "promote_secondaries"), 1508 }, 1509 }; 1510 1511 static int __devinet_sysctl_register(struct net *net, char *dev_name, 1512 struct ipv4_devconf *p) 1513 { 1514 int i; 1515 struct devinet_sysctl_table *t; 1516 1517 #define DEVINET_CTL_PATH_DEV 3 1518 1519 struct ctl_path devinet_ctl_path[] = { 1520 { .procname = "net", }, 1521 { .procname = "ipv4", }, 1522 { .procname = "conf", }, 1523 { /* to be set */ }, 1524 { }, 1525 }; 1526 1527 t = kmemdup(&devinet_sysctl, sizeof(*t), GFP_KERNEL); 1528 if (!t) 1529 goto out; 1530 1531 for (i = 0; i < ARRAY_SIZE(t->devinet_vars) - 1; i++) { 1532 t->devinet_vars[i].data += (char *)p - (char *)&ipv4_devconf; 1533 t->devinet_vars[i].extra1 = p; 1534 t->devinet_vars[i].extra2 = net; 1535 } 1536 1537 /* 1538 * Make a copy of dev_name, because '.procname' is regarded as const 1539 * by sysctl and we wouldn't want anyone to change it under our feet 1540 * (see SIOCSIFNAME). 1541 */ 1542 t->dev_name = kstrdup(dev_name, GFP_KERNEL); 1543 if (!t->dev_name) 1544 goto free; 1545 1546 devinet_ctl_path[DEVINET_CTL_PATH_DEV].procname = t->dev_name; 1547 1548 t->sysctl_header = register_net_sysctl_table(net, devinet_ctl_path, 1549 t->devinet_vars); 1550 if (!t->sysctl_header) 1551 goto free_procname; 1552 1553 p->sysctl = t; 1554 return 0; 1555 1556 free_procname: 1557 kfree(t->dev_name); 1558 free: 1559 kfree(t); 1560 out: 1561 return -ENOBUFS; 1562 } 1563 1564 static void __devinet_sysctl_unregister(struct ipv4_devconf *cnf) 1565 { 1566 struct devinet_sysctl_table *t = cnf->sysctl; 1567 1568 if (t == NULL) 1569 return; 1570 1571 cnf->sysctl = NULL; 1572 unregister_sysctl_table(t->sysctl_header); 1573 kfree(t->dev_name); 1574 kfree(t); 1575 } 1576 1577 static void devinet_sysctl_register(struct in_device *idev) 1578 { 1579 neigh_sysctl_register(idev->dev, idev->arp_parms, "ipv4", NULL); 1580 __devinet_sysctl_register(dev_net(idev->dev), idev->dev->name, 1581 &idev->cnf); 1582 } 1583 1584 static void devinet_sysctl_unregister(struct in_device *idev) 1585 { 1586 __devinet_sysctl_unregister(&idev->cnf); 1587 neigh_sysctl_unregister(idev->arp_parms); 1588 } 1589 1590 static struct ctl_table ctl_forward_entry[] = { 1591 { 1592 .procname = "ip_forward", 1593 .data = &ipv4_devconf.data[ 1594 IPV4_DEVCONF_FORWARDING - 1], 1595 .maxlen = sizeof(int), 1596 .mode = 0644, 1597 .proc_handler = devinet_sysctl_forward, 1598 .extra1 = &ipv4_devconf, 1599 .extra2 = &init_net, 1600 }, 1601 { }, 1602 }; 1603 1604 static __net_initdata struct ctl_path net_ipv4_path[] = { 1605 { .procname = "net", }, 1606 { .procname = "ipv4", }, 1607 { }, 1608 }; 1609 #endif 1610 1611 static __net_init int devinet_init_net(struct net *net) 1612 { 1613 int err; 1614 struct ipv4_devconf *all, *dflt; 1615 #ifdef CONFIG_SYSCTL 1616 struct ctl_table *tbl = ctl_forward_entry; 1617 struct ctl_table_header *forw_hdr; 1618 #endif 1619 1620 err = -ENOMEM; 1621 all = &ipv4_devconf; 1622 dflt = &ipv4_devconf_dflt; 1623 1624 if (!net_eq(net, &init_net)) { 1625 all = kmemdup(all, sizeof(ipv4_devconf), GFP_KERNEL); 1626 if (all == NULL) 1627 goto err_alloc_all; 1628 1629 dflt = kmemdup(dflt, sizeof(ipv4_devconf_dflt), GFP_KERNEL); 1630 if (dflt == NULL) 1631 goto err_alloc_dflt; 1632 1633 #ifdef CONFIG_SYSCTL 1634 tbl = kmemdup(tbl, sizeof(ctl_forward_entry), GFP_KERNEL); 1635 if (tbl == NULL) 1636 goto err_alloc_ctl; 1637 1638 tbl[0].data = &all->data[IPV4_DEVCONF_FORWARDING - 1]; 1639 tbl[0].extra1 = all; 1640 tbl[0].extra2 = net; 1641 #endif 1642 } 1643 1644 #ifdef CONFIG_SYSCTL 1645 err = __devinet_sysctl_register(net, "all", all); 1646 if (err < 0) 1647 goto err_reg_all; 1648 1649 err = __devinet_sysctl_register(net, "default", dflt); 1650 if (err < 0) 1651 goto err_reg_dflt; 1652 1653 err = -ENOMEM; 1654 forw_hdr = register_net_sysctl_table(net, net_ipv4_path, tbl); 1655 if (forw_hdr == NULL) 1656 goto err_reg_ctl; 1657 net->ipv4.forw_hdr = forw_hdr; 1658 #endif 1659 1660 net->ipv4.devconf_all = all; 1661 net->ipv4.devconf_dflt = dflt; 1662 return 0; 1663 1664 #ifdef CONFIG_SYSCTL 1665 err_reg_ctl: 1666 __devinet_sysctl_unregister(dflt); 1667 err_reg_dflt: 1668 __devinet_sysctl_unregister(all); 1669 err_reg_all: 1670 if (tbl != ctl_forward_entry) 1671 kfree(tbl); 1672 err_alloc_ctl: 1673 #endif 1674 if (dflt != &ipv4_devconf_dflt) 1675 kfree(dflt); 1676 err_alloc_dflt: 1677 if (all != &ipv4_devconf) 1678 kfree(all); 1679 err_alloc_all: 1680 return err; 1681 } 1682 1683 static __net_exit void devinet_exit_net(struct net *net) 1684 { 1685 #ifdef CONFIG_SYSCTL 1686 struct ctl_table *tbl; 1687 1688 tbl = net->ipv4.forw_hdr->ctl_table_arg; 1689 unregister_net_sysctl_table(net->ipv4.forw_hdr); 1690 __devinet_sysctl_unregister(net->ipv4.devconf_dflt); 1691 __devinet_sysctl_unregister(net->ipv4.devconf_all); 1692 kfree(tbl); 1693 #endif 1694 kfree(net->ipv4.devconf_dflt); 1695 kfree(net->ipv4.devconf_all); 1696 } 1697 1698 static __net_initdata struct pernet_operations devinet_ops = { 1699 .init = devinet_init_net, 1700 .exit = devinet_exit_net, 1701 }; 1702 1703 static struct rtnl_af_ops inet_af_ops = { 1704 .family = AF_INET, 1705 .fill_link_af = inet_fill_link_af, 1706 .get_link_af_size = inet_get_link_af_size, 1707 .validate_link_af = inet_validate_link_af, 1708 .set_link_af = inet_set_link_af, 1709 }; 1710 1711 void __init devinet_init(void) 1712 { 1713 register_pernet_subsys(&devinet_ops); 1714 1715 register_gifconf(PF_INET, inet_gifconf); 1716 register_netdevice_notifier(&ip_netdev_notifier); 1717 1718 rtnl_af_register(&inet_af_ops); 1719 1720 rtnl_register(PF_INET, RTM_NEWADDR, inet_rtm_newaddr, NULL); 1721 rtnl_register(PF_INET, RTM_DELADDR, inet_rtm_deladdr, NULL); 1722 rtnl_register(PF_INET, RTM_GETADDR, NULL, inet_dump_ifaddr); 1723 } 1724 1725