1 /* 2 * IP multicast routing support for mrouted 3.6/3.8 3 * 4 * (c) 1995 Alan Cox, <alan@redhat.com> 5 * Linux Consultancy and Custom Driver Development 6 * 7 * This program is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU General Public License 9 * as published by the Free Software Foundation; either version 10 * 2 of the License, or (at your option) any later version. 11 * 12 * Version: $Id: ipmr.c,v 1.65 2001/10/31 21:55:54 davem Exp $ 13 * 14 * Fixes: 15 * Michael Chastain : Incorrect size of copying. 16 * Alan Cox : Added the cache manager code 17 * Alan Cox : Fixed the clone/copy bug and device race. 18 * Mike McLagan : Routing by source 19 * Malcolm Beattie : Buffer handling fixes. 20 * Alexey Kuznetsov : Double buffer free and other fixes. 21 * SVR Anand : Fixed several multicast bugs and problems. 22 * Alexey Kuznetsov : Status, optimisations and more. 23 * Brad Parker : Better behaviour on mrouted upcall 24 * overflow. 25 * Carlos Picoto : PIMv1 Support 26 * Pavlin Ivanov Radoslavov: PIMv2 Registers must checksum only PIM header 27 * Relax this requrement to work with older peers. 28 * 29 */ 30 31 #include <asm/system.h> 32 #include <asm/uaccess.h> 33 #include <linux/types.h> 34 #include <linux/sched.h> 35 #include <linux/capability.h> 36 #include <linux/errno.h> 37 #include <linux/timer.h> 38 #include <linux/mm.h> 39 #include <linux/kernel.h> 40 #include <linux/fcntl.h> 41 #include <linux/stat.h> 42 #include <linux/socket.h> 43 #include <linux/in.h> 44 #include <linux/inet.h> 45 #include <linux/netdevice.h> 46 #include <linux/inetdevice.h> 47 #include <linux/igmp.h> 48 #include <linux/proc_fs.h> 49 #include <linux/seq_file.h> 50 #include <linux/mroute.h> 51 #include <linux/init.h> 52 #include <linux/if_ether.h> 53 #include <net/ip.h> 54 #include <net/protocol.h> 55 #include <linux/skbuff.h> 56 #include <net/route.h> 57 #include <net/sock.h> 58 #include <net/icmp.h> 59 #include <net/udp.h> 60 #include <net/raw.h> 61 #include <linux/notifier.h> 62 #include <linux/if_arp.h> 63 #include <linux/netfilter_ipv4.h> 64 #include <net/ipip.h> 65 #include <net/checksum.h> 66 67 #if defined(CONFIG_IP_PIMSM_V1) || defined(CONFIG_IP_PIMSM_V2) 68 #define CONFIG_IP_PIMSM 1 69 #endif 70 71 static struct sock *mroute_socket; 72 73 74 /* Big lock, protecting vif table, mrt cache and mroute socket state. 75 Note that the changes are semaphored via rtnl_lock. 76 */ 77 78 static DEFINE_RWLOCK(mrt_lock); 79 80 /* 81 * Multicast router control variables 82 */ 83 84 static struct vif_device vif_table[MAXVIFS]; /* Devices */ 85 static int maxvif; 86 87 #define VIF_EXISTS(idx) (vif_table[idx].dev != NULL) 88 89 static int mroute_do_assert; /* Set in PIM assert */ 90 static int mroute_do_pim; 91 92 static struct mfc_cache *mfc_cache_array[MFC_LINES]; /* Forwarding cache */ 93 94 static struct mfc_cache *mfc_unres_queue; /* Queue of unresolved entries */ 95 static atomic_t cache_resolve_queue_len; /* Size of unresolved */ 96 97 /* Special spinlock for queue of unresolved entries */ 98 static DEFINE_SPINLOCK(mfc_unres_lock); 99 100 /* We return to original Alan's scheme. Hash table of resolved 101 entries is changed only in process context and protected 102 with weak lock mrt_lock. Queue of unresolved entries is protected 103 with strong spinlock mfc_unres_lock. 104 105 In this case data path is free of exclusive locks at all. 106 */ 107 108 static struct kmem_cache *mrt_cachep __read_mostly; 109 110 static int ip_mr_forward(struct sk_buff *skb, struct mfc_cache *cache, int local); 111 static int ipmr_cache_report(struct sk_buff *pkt, vifi_t vifi, int assert); 112 static int ipmr_fill_mroute(struct sk_buff *skb, struct mfc_cache *c, struct rtmsg *rtm); 113 114 #ifdef CONFIG_IP_PIMSM_V2 115 static struct net_protocol pim_protocol; 116 #endif 117 118 static struct timer_list ipmr_expire_timer; 119 120 /* Service routines creating virtual interfaces: DVMRP tunnels and PIMREG */ 121 122 static 123 struct net_device *ipmr_new_tunnel(struct vifctl *v) 124 { 125 struct net_device *dev; 126 127 dev = __dev_get_by_name("tunl0"); 128 129 if (dev) { 130 int err; 131 struct ifreq ifr; 132 mm_segment_t oldfs; 133 struct ip_tunnel_parm p; 134 struct in_device *in_dev; 135 136 memset(&p, 0, sizeof(p)); 137 p.iph.daddr = v->vifc_rmt_addr.s_addr; 138 p.iph.saddr = v->vifc_lcl_addr.s_addr; 139 p.iph.version = 4; 140 p.iph.ihl = 5; 141 p.iph.protocol = IPPROTO_IPIP; 142 sprintf(p.name, "dvmrp%d", v->vifc_vifi); 143 ifr.ifr_ifru.ifru_data = (void*)&p; 144 145 oldfs = get_fs(); set_fs(KERNEL_DS); 146 err = dev->do_ioctl(dev, &ifr, SIOCADDTUNNEL); 147 set_fs(oldfs); 148 149 dev = NULL; 150 151 if (err == 0 && (dev = __dev_get_by_name(p.name)) != NULL) { 152 dev->flags |= IFF_MULTICAST; 153 154 in_dev = __in_dev_get_rtnl(dev); 155 if (in_dev == NULL && (in_dev = inetdev_init(dev)) == NULL) 156 goto failure; 157 in_dev->cnf.rp_filter = 0; 158 159 if (dev_open(dev)) 160 goto failure; 161 } 162 } 163 return dev; 164 165 failure: 166 /* allow the register to be completed before unregistering. */ 167 rtnl_unlock(); 168 rtnl_lock(); 169 170 unregister_netdevice(dev); 171 return NULL; 172 } 173 174 #ifdef CONFIG_IP_PIMSM 175 176 static int reg_vif_num = -1; 177 178 static int reg_vif_xmit(struct sk_buff *skb, struct net_device *dev) 179 { 180 read_lock(&mrt_lock); 181 ((struct net_device_stats*)netdev_priv(dev))->tx_bytes += skb->len; 182 ((struct net_device_stats*)netdev_priv(dev))->tx_packets++; 183 ipmr_cache_report(skb, reg_vif_num, IGMPMSG_WHOLEPKT); 184 read_unlock(&mrt_lock); 185 kfree_skb(skb); 186 return 0; 187 } 188 189 static struct net_device_stats *reg_vif_get_stats(struct net_device *dev) 190 { 191 return (struct net_device_stats*)netdev_priv(dev); 192 } 193 194 static void reg_vif_setup(struct net_device *dev) 195 { 196 dev->type = ARPHRD_PIMREG; 197 dev->mtu = ETH_DATA_LEN - sizeof(struct iphdr) - 8; 198 dev->flags = IFF_NOARP; 199 dev->hard_start_xmit = reg_vif_xmit; 200 dev->get_stats = reg_vif_get_stats; 201 dev->destructor = free_netdev; 202 } 203 204 static struct net_device *ipmr_reg_vif(void) 205 { 206 struct net_device *dev; 207 struct in_device *in_dev; 208 209 dev = alloc_netdev(sizeof(struct net_device_stats), "pimreg", 210 reg_vif_setup); 211 212 if (dev == NULL) 213 return NULL; 214 215 if (register_netdevice(dev)) { 216 free_netdev(dev); 217 return NULL; 218 } 219 dev->iflink = 0; 220 221 if ((in_dev = inetdev_init(dev)) == NULL) 222 goto failure; 223 224 in_dev->cnf.rp_filter = 0; 225 226 if (dev_open(dev)) 227 goto failure; 228 229 return dev; 230 231 failure: 232 /* allow the register to be completed before unregistering. */ 233 rtnl_unlock(); 234 rtnl_lock(); 235 236 unregister_netdevice(dev); 237 return NULL; 238 } 239 #endif 240 241 /* 242 * Delete a VIF entry 243 */ 244 245 static int vif_delete(int vifi) 246 { 247 struct vif_device *v; 248 struct net_device *dev; 249 struct in_device *in_dev; 250 251 if (vifi < 0 || vifi >= maxvif) 252 return -EADDRNOTAVAIL; 253 254 v = &vif_table[vifi]; 255 256 write_lock_bh(&mrt_lock); 257 dev = v->dev; 258 v->dev = NULL; 259 260 if (!dev) { 261 write_unlock_bh(&mrt_lock); 262 return -EADDRNOTAVAIL; 263 } 264 265 #ifdef CONFIG_IP_PIMSM 266 if (vifi == reg_vif_num) 267 reg_vif_num = -1; 268 #endif 269 270 if (vifi+1 == maxvif) { 271 int tmp; 272 for (tmp=vifi-1; tmp>=0; tmp--) { 273 if (VIF_EXISTS(tmp)) 274 break; 275 } 276 maxvif = tmp+1; 277 } 278 279 write_unlock_bh(&mrt_lock); 280 281 dev_set_allmulti(dev, -1); 282 283 if ((in_dev = __in_dev_get_rtnl(dev)) != NULL) { 284 in_dev->cnf.mc_forwarding--; 285 ip_rt_multicast_event(in_dev); 286 } 287 288 if (v->flags&(VIFF_TUNNEL|VIFF_REGISTER)) 289 unregister_netdevice(dev); 290 291 dev_put(dev); 292 return 0; 293 } 294 295 /* Destroy an unresolved cache entry, killing queued skbs 296 and reporting error to netlink readers. 297 */ 298 299 static void ipmr_destroy_unres(struct mfc_cache *c) 300 { 301 struct sk_buff *skb; 302 struct nlmsgerr *e; 303 304 atomic_dec(&cache_resolve_queue_len); 305 306 while((skb=skb_dequeue(&c->mfc_un.unres.unresolved))) { 307 if (skb->nh.iph->version == 0) { 308 struct nlmsghdr *nlh = (struct nlmsghdr *)skb_pull(skb, sizeof(struct iphdr)); 309 nlh->nlmsg_type = NLMSG_ERROR; 310 nlh->nlmsg_len = NLMSG_LENGTH(sizeof(struct nlmsgerr)); 311 skb_trim(skb, nlh->nlmsg_len); 312 e = NLMSG_DATA(nlh); 313 e->error = -ETIMEDOUT; 314 memset(&e->msg, 0, sizeof(e->msg)); 315 316 rtnl_unicast(skb, NETLINK_CB(skb).pid); 317 } else 318 kfree_skb(skb); 319 } 320 321 kmem_cache_free(mrt_cachep, c); 322 } 323 324 325 /* Single timer process for all the unresolved queue. */ 326 327 static void ipmr_expire_process(unsigned long dummy) 328 { 329 unsigned long now; 330 unsigned long expires; 331 struct mfc_cache *c, **cp; 332 333 if (!spin_trylock(&mfc_unres_lock)) { 334 mod_timer(&ipmr_expire_timer, jiffies+HZ/10); 335 return; 336 } 337 338 if (atomic_read(&cache_resolve_queue_len) == 0) 339 goto out; 340 341 now = jiffies; 342 expires = 10*HZ; 343 cp = &mfc_unres_queue; 344 345 while ((c=*cp) != NULL) { 346 if (time_after(c->mfc_un.unres.expires, now)) { 347 unsigned long interval = c->mfc_un.unres.expires - now; 348 if (interval < expires) 349 expires = interval; 350 cp = &c->next; 351 continue; 352 } 353 354 *cp = c->next; 355 356 ipmr_destroy_unres(c); 357 } 358 359 if (atomic_read(&cache_resolve_queue_len)) 360 mod_timer(&ipmr_expire_timer, jiffies + expires); 361 362 out: 363 spin_unlock(&mfc_unres_lock); 364 } 365 366 /* Fill oifs list. It is called under write locked mrt_lock. */ 367 368 static void ipmr_update_thresholds(struct mfc_cache *cache, unsigned char *ttls) 369 { 370 int vifi; 371 372 cache->mfc_un.res.minvif = MAXVIFS; 373 cache->mfc_un.res.maxvif = 0; 374 memset(cache->mfc_un.res.ttls, 255, MAXVIFS); 375 376 for (vifi=0; vifi<maxvif; vifi++) { 377 if (VIF_EXISTS(vifi) && ttls[vifi] && ttls[vifi] < 255) { 378 cache->mfc_un.res.ttls[vifi] = ttls[vifi]; 379 if (cache->mfc_un.res.minvif > vifi) 380 cache->mfc_un.res.minvif = vifi; 381 if (cache->mfc_un.res.maxvif <= vifi) 382 cache->mfc_un.res.maxvif = vifi + 1; 383 } 384 } 385 } 386 387 static int vif_add(struct vifctl *vifc, int mrtsock) 388 { 389 int vifi = vifc->vifc_vifi; 390 struct vif_device *v = &vif_table[vifi]; 391 struct net_device *dev; 392 struct in_device *in_dev; 393 394 /* Is vif busy ? */ 395 if (VIF_EXISTS(vifi)) 396 return -EADDRINUSE; 397 398 switch (vifc->vifc_flags) { 399 #ifdef CONFIG_IP_PIMSM 400 case VIFF_REGISTER: 401 /* 402 * Special Purpose VIF in PIM 403 * All the packets will be sent to the daemon 404 */ 405 if (reg_vif_num >= 0) 406 return -EADDRINUSE; 407 dev = ipmr_reg_vif(); 408 if (!dev) 409 return -ENOBUFS; 410 break; 411 #endif 412 case VIFF_TUNNEL: 413 dev = ipmr_new_tunnel(vifc); 414 if (!dev) 415 return -ENOBUFS; 416 break; 417 case 0: 418 dev = ip_dev_find(vifc->vifc_lcl_addr.s_addr); 419 if (!dev) 420 return -EADDRNOTAVAIL; 421 dev_put(dev); 422 break; 423 default: 424 return -EINVAL; 425 } 426 427 if ((in_dev = __in_dev_get_rtnl(dev)) == NULL) 428 return -EADDRNOTAVAIL; 429 in_dev->cnf.mc_forwarding++; 430 dev_set_allmulti(dev, +1); 431 ip_rt_multicast_event(in_dev); 432 433 /* 434 * Fill in the VIF structures 435 */ 436 v->rate_limit=vifc->vifc_rate_limit; 437 v->local=vifc->vifc_lcl_addr.s_addr; 438 v->remote=vifc->vifc_rmt_addr.s_addr; 439 v->flags=vifc->vifc_flags; 440 if (!mrtsock) 441 v->flags |= VIFF_STATIC; 442 v->threshold=vifc->vifc_threshold; 443 v->bytes_in = 0; 444 v->bytes_out = 0; 445 v->pkt_in = 0; 446 v->pkt_out = 0; 447 v->link = dev->ifindex; 448 if (v->flags&(VIFF_TUNNEL|VIFF_REGISTER)) 449 v->link = dev->iflink; 450 451 /* And finish update writing critical data */ 452 write_lock_bh(&mrt_lock); 453 dev_hold(dev); 454 v->dev=dev; 455 #ifdef CONFIG_IP_PIMSM 456 if (v->flags&VIFF_REGISTER) 457 reg_vif_num = vifi; 458 #endif 459 if (vifi+1 > maxvif) 460 maxvif = vifi+1; 461 write_unlock_bh(&mrt_lock); 462 return 0; 463 } 464 465 static struct mfc_cache *ipmr_cache_find(__be32 origin, __be32 mcastgrp) 466 { 467 int line=MFC_HASH(mcastgrp,origin); 468 struct mfc_cache *c; 469 470 for (c=mfc_cache_array[line]; c; c = c->next) { 471 if (c->mfc_origin==origin && c->mfc_mcastgrp==mcastgrp) 472 break; 473 } 474 return c; 475 } 476 477 /* 478 * Allocate a multicast cache entry 479 */ 480 static struct mfc_cache *ipmr_cache_alloc(void) 481 { 482 struct mfc_cache *c=kmem_cache_alloc(mrt_cachep, GFP_KERNEL); 483 if(c==NULL) 484 return NULL; 485 memset(c, 0, sizeof(*c)); 486 c->mfc_un.res.minvif = MAXVIFS; 487 return c; 488 } 489 490 static struct mfc_cache *ipmr_cache_alloc_unres(void) 491 { 492 struct mfc_cache *c=kmem_cache_alloc(mrt_cachep, GFP_ATOMIC); 493 if(c==NULL) 494 return NULL; 495 memset(c, 0, sizeof(*c)); 496 skb_queue_head_init(&c->mfc_un.unres.unresolved); 497 c->mfc_un.unres.expires = jiffies + 10*HZ; 498 return c; 499 } 500 501 /* 502 * A cache entry has gone into a resolved state from queued 503 */ 504 505 static void ipmr_cache_resolve(struct mfc_cache *uc, struct mfc_cache *c) 506 { 507 struct sk_buff *skb; 508 struct nlmsgerr *e; 509 510 /* 511 * Play the pending entries through our router 512 */ 513 514 while((skb=__skb_dequeue(&uc->mfc_un.unres.unresolved))) { 515 if (skb->nh.iph->version == 0) { 516 struct nlmsghdr *nlh = (struct nlmsghdr *)skb_pull(skb, sizeof(struct iphdr)); 517 518 if (ipmr_fill_mroute(skb, c, NLMSG_DATA(nlh)) > 0) { 519 nlh->nlmsg_len = skb->tail - (u8*)nlh; 520 } else { 521 nlh->nlmsg_type = NLMSG_ERROR; 522 nlh->nlmsg_len = NLMSG_LENGTH(sizeof(struct nlmsgerr)); 523 skb_trim(skb, nlh->nlmsg_len); 524 e = NLMSG_DATA(nlh); 525 e->error = -EMSGSIZE; 526 memset(&e->msg, 0, sizeof(e->msg)); 527 } 528 529 rtnl_unicast(skb, NETLINK_CB(skb).pid); 530 } else 531 ip_mr_forward(skb, c, 0); 532 } 533 } 534 535 /* 536 * Bounce a cache query up to mrouted. We could use netlink for this but mrouted 537 * expects the following bizarre scheme. 538 * 539 * Called under mrt_lock. 540 */ 541 542 static int ipmr_cache_report(struct sk_buff *pkt, vifi_t vifi, int assert) 543 { 544 struct sk_buff *skb; 545 int ihl = pkt->nh.iph->ihl<<2; 546 struct igmphdr *igmp; 547 struct igmpmsg *msg; 548 int ret; 549 550 #ifdef CONFIG_IP_PIMSM 551 if (assert == IGMPMSG_WHOLEPKT) 552 skb = skb_realloc_headroom(pkt, sizeof(struct iphdr)); 553 else 554 #endif 555 skb = alloc_skb(128, GFP_ATOMIC); 556 557 if(!skb) 558 return -ENOBUFS; 559 560 #ifdef CONFIG_IP_PIMSM 561 if (assert == IGMPMSG_WHOLEPKT) { 562 /* Ugly, but we have no choice with this interface. 563 Duplicate old header, fix ihl, length etc. 564 And all this only to mangle msg->im_msgtype and 565 to set msg->im_mbz to "mbz" :-) 566 */ 567 msg = (struct igmpmsg*)skb_push(skb, sizeof(struct iphdr)); 568 skb->nh.raw = skb->h.raw = (u8*)msg; 569 memcpy(msg, pkt->nh.raw, sizeof(struct iphdr)); 570 msg->im_msgtype = IGMPMSG_WHOLEPKT; 571 msg->im_mbz = 0; 572 msg->im_vif = reg_vif_num; 573 skb->nh.iph->ihl = sizeof(struct iphdr) >> 2; 574 skb->nh.iph->tot_len = htons(ntohs(pkt->nh.iph->tot_len) + sizeof(struct iphdr)); 575 } else 576 #endif 577 { 578 579 /* 580 * Copy the IP header 581 */ 582 583 skb->nh.iph = (struct iphdr *)skb_put(skb, ihl); 584 memcpy(skb->data,pkt->data,ihl); 585 skb->nh.iph->protocol = 0; /* Flag to the kernel this is a route add */ 586 msg = (struct igmpmsg*)skb->nh.iph; 587 msg->im_vif = vifi; 588 skb->dst = dst_clone(pkt->dst); 589 590 /* 591 * Add our header 592 */ 593 594 igmp=(struct igmphdr *)skb_put(skb,sizeof(struct igmphdr)); 595 igmp->type = 596 msg->im_msgtype = assert; 597 igmp->code = 0; 598 skb->nh.iph->tot_len=htons(skb->len); /* Fix the length */ 599 skb->h.raw = skb->nh.raw; 600 } 601 602 if (mroute_socket == NULL) { 603 kfree_skb(skb); 604 return -EINVAL; 605 } 606 607 /* 608 * Deliver to mrouted 609 */ 610 if ((ret=sock_queue_rcv_skb(mroute_socket,skb))<0) { 611 if (net_ratelimit()) 612 printk(KERN_WARNING "mroute: pending queue full, dropping entries.\n"); 613 kfree_skb(skb); 614 } 615 616 return ret; 617 } 618 619 /* 620 * Queue a packet for resolution. It gets locked cache entry! 621 */ 622 623 static int 624 ipmr_cache_unresolved(vifi_t vifi, struct sk_buff *skb) 625 { 626 int err; 627 struct mfc_cache *c; 628 629 spin_lock_bh(&mfc_unres_lock); 630 for (c=mfc_unres_queue; c; c=c->next) { 631 if (c->mfc_mcastgrp == skb->nh.iph->daddr && 632 c->mfc_origin == skb->nh.iph->saddr) 633 break; 634 } 635 636 if (c == NULL) { 637 /* 638 * Create a new entry if allowable 639 */ 640 641 if (atomic_read(&cache_resolve_queue_len)>=10 || 642 (c=ipmr_cache_alloc_unres())==NULL) { 643 spin_unlock_bh(&mfc_unres_lock); 644 645 kfree_skb(skb); 646 return -ENOBUFS; 647 } 648 649 /* 650 * Fill in the new cache entry 651 */ 652 c->mfc_parent=-1; 653 c->mfc_origin=skb->nh.iph->saddr; 654 c->mfc_mcastgrp=skb->nh.iph->daddr; 655 656 /* 657 * Reflect first query at mrouted. 658 */ 659 if ((err = ipmr_cache_report(skb, vifi, IGMPMSG_NOCACHE))<0) { 660 /* If the report failed throw the cache entry 661 out - Brad Parker 662 */ 663 spin_unlock_bh(&mfc_unres_lock); 664 665 kmem_cache_free(mrt_cachep, c); 666 kfree_skb(skb); 667 return err; 668 } 669 670 atomic_inc(&cache_resolve_queue_len); 671 c->next = mfc_unres_queue; 672 mfc_unres_queue = c; 673 674 mod_timer(&ipmr_expire_timer, c->mfc_un.unres.expires); 675 } 676 677 /* 678 * See if we can append the packet 679 */ 680 if (c->mfc_un.unres.unresolved.qlen>3) { 681 kfree_skb(skb); 682 err = -ENOBUFS; 683 } else { 684 skb_queue_tail(&c->mfc_un.unres.unresolved,skb); 685 err = 0; 686 } 687 688 spin_unlock_bh(&mfc_unres_lock); 689 return err; 690 } 691 692 /* 693 * MFC cache manipulation by user space mroute daemon 694 */ 695 696 static int ipmr_mfc_delete(struct mfcctl *mfc) 697 { 698 int line; 699 struct mfc_cache *c, **cp; 700 701 line=MFC_HASH(mfc->mfcc_mcastgrp.s_addr, mfc->mfcc_origin.s_addr); 702 703 for (cp=&mfc_cache_array[line]; (c=*cp) != NULL; cp = &c->next) { 704 if (c->mfc_origin == mfc->mfcc_origin.s_addr && 705 c->mfc_mcastgrp == mfc->mfcc_mcastgrp.s_addr) { 706 write_lock_bh(&mrt_lock); 707 *cp = c->next; 708 write_unlock_bh(&mrt_lock); 709 710 kmem_cache_free(mrt_cachep, c); 711 return 0; 712 } 713 } 714 return -ENOENT; 715 } 716 717 static int ipmr_mfc_add(struct mfcctl *mfc, int mrtsock) 718 { 719 int line; 720 struct mfc_cache *uc, *c, **cp; 721 722 line=MFC_HASH(mfc->mfcc_mcastgrp.s_addr, mfc->mfcc_origin.s_addr); 723 724 for (cp=&mfc_cache_array[line]; (c=*cp) != NULL; cp = &c->next) { 725 if (c->mfc_origin == mfc->mfcc_origin.s_addr && 726 c->mfc_mcastgrp == mfc->mfcc_mcastgrp.s_addr) 727 break; 728 } 729 730 if (c != NULL) { 731 write_lock_bh(&mrt_lock); 732 c->mfc_parent = mfc->mfcc_parent; 733 ipmr_update_thresholds(c, mfc->mfcc_ttls); 734 if (!mrtsock) 735 c->mfc_flags |= MFC_STATIC; 736 write_unlock_bh(&mrt_lock); 737 return 0; 738 } 739 740 if(!MULTICAST(mfc->mfcc_mcastgrp.s_addr)) 741 return -EINVAL; 742 743 c=ipmr_cache_alloc(); 744 if (c==NULL) 745 return -ENOMEM; 746 747 c->mfc_origin=mfc->mfcc_origin.s_addr; 748 c->mfc_mcastgrp=mfc->mfcc_mcastgrp.s_addr; 749 c->mfc_parent=mfc->mfcc_parent; 750 ipmr_update_thresholds(c, mfc->mfcc_ttls); 751 if (!mrtsock) 752 c->mfc_flags |= MFC_STATIC; 753 754 write_lock_bh(&mrt_lock); 755 c->next = mfc_cache_array[line]; 756 mfc_cache_array[line] = c; 757 write_unlock_bh(&mrt_lock); 758 759 /* 760 * Check to see if we resolved a queued list. If so we 761 * need to send on the frames and tidy up. 762 */ 763 spin_lock_bh(&mfc_unres_lock); 764 for (cp = &mfc_unres_queue; (uc=*cp) != NULL; 765 cp = &uc->next) { 766 if (uc->mfc_origin == c->mfc_origin && 767 uc->mfc_mcastgrp == c->mfc_mcastgrp) { 768 *cp = uc->next; 769 if (atomic_dec_and_test(&cache_resolve_queue_len)) 770 del_timer(&ipmr_expire_timer); 771 break; 772 } 773 } 774 spin_unlock_bh(&mfc_unres_lock); 775 776 if (uc) { 777 ipmr_cache_resolve(uc, c); 778 kmem_cache_free(mrt_cachep, uc); 779 } 780 return 0; 781 } 782 783 /* 784 * Close the multicast socket, and clear the vif tables etc 785 */ 786 787 static void mroute_clean_tables(struct sock *sk) 788 { 789 int i; 790 791 /* 792 * Shut down all active vif entries 793 */ 794 for(i=0; i<maxvif; i++) { 795 if (!(vif_table[i].flags&VIFF_STATIC)) 796 vif_delete(i); 797 } 798 799 /* 800 * Wipe the cache 801 */ 802 for (i=0;i<MFC_LINES;i++) { 803 struct mfc_cache *c, **cp; 804 805 cp = &mfc_cache_array[i]; 806 while ((c = *cp) != NULL) { 807 if (c->mfc_flags&MFC_STATIC) { 808 cp = &c->next; 809 continue; 810 } 811 write_lock_bh(&mrt_lock); 812 *cp = c->next; 813 write_unlock_bh(&mrt_lock); 814 815 kmem_cache_free(mrt_cachep, c); 816 } 817 } 818 819 if (atomic_read(&cache_resolve_queue_len) != 0) { 820 struct mfc_cache *c; 821 822 spin_lock_bh(&mfc_unres_lock); 823 while (mfc_unres_queue != NULL) { 824 c = mfc_unres_queue; 825 mfc_unres_queue = c->next; 826 spin_unlock_bh(&mfc_unres_lock); 827 828 ipmr_destroy_unres(c); 829 830 spin_lock_bh(&mfc_unres_lock); 831 } 832 spin_unlock_bh(&mfc_unres_lock); 833 } 834 } 835 836 static void mrtsock_destruct(struct sock *sk) 837 { 838 rtnl_lock(); 839 if (sk == mroute_socket) { 840 ipv4_devconf.mc_forwarding--; 841 842 write_lock_bh(&mrt_lock); 843 mroute_socket=NULL; 844 write_unlock_bh(&mrt_lock); 845 846 mroute_clean_tables(sk); 847 } 848 rtnl_unlock(); 849 } 850 851 /* 852 * Socket options and virtual interface manipulation. The whole 853 * virtual interface system is a complete heap, but unfortunately 854 * that's how BSD mrouted happens to think. Maybe one day with a proper 855 * MOSPF/PIM router set up we can clean this up. 856 */ 857 858 int ip_mroute_setsockopt(struct sock *sk,int optname,char __user *optval,int optlen) 859 { 860 int ret; 861 struct vifctl vif; 862 struct mfcctl mfc; 863 864 if(optname!=MRT_INIT) 865 { 866 if(sk!=mroute_socket && !capable(CAP_NET_ADMIN)) 867 return -EACCES; 868 } 869 870 switch(optname) 871 { 872 case MRT_INIT: 873 if (sk->sk_type != SOCK_RAW || 874 inet_sk(sk)->num != IPPROTO_IGMP) 875 return -EOPNOTSUPP; 876 if(optlen!=sizeof(int)) 877 return -ENOPROTOOPT; 878 879 rtnl_lock(); 880 if (mroute_socket) { 881 rtnl_unlock(); 882 return -EADDRINUSE; 883 } 884 885 ret = ip_ra_control(sk, 1, mrtsock_destruct); 886 if (ret == 0) { 887 write_lock_bh(&mrt_lock); 888 mroute_socket=sk; 889 write_unlock_bh(&mrt_lock); 890 891 ipv4_devconf.mc_forwarding++; 892 } 893 rtnl_unlock(); 894 return ret; 895 case MRT_DONE: 896 if (sk!=mroute_socket) 897 return -EACCES; 898 return ip_ra_control(sk, 0, NULL); 899 case MRT_ADD_VIF: 900 case MRT_DEL_VIF: 901 if(optlen!=sizeof(vif)) 902 return -EINVAL; 903 if (copy_from_user(&vif,optval,sizeof(vif))) 904 return -EFAULT; 905 if(vif.vifc_vifi >= MAXVIFS) 906 return -ENFILE; 907 rtnl_lock(); 908 if (optname==MRT_ADD_VIF) { 909 ret = vif_add(&vif, sk==mroute_socket); 910 } else { 911 ret = vif_delete(vif.vifc_vifi); 912 } 913 rtnl_unlock(); 914 return ret; 915 916 /* 917 * Manipulate the forwarding caches. These live 918 * in a sort of kernel/user symbiosis. 919 */ 920 case MRT_ADD_MFC: 921 case MRT_DEL_MFC: 922 if(optlen!=sizeof(mfc)) 923 return -EINVAL; 924 if (copy_from_user(&mfc,optval, sizeof(mfc))) 925 return -EFAULT; 926 rtnl_lock(); 927 if (optname==MRT_DEL_MFC) 928 ret = ipmr_mfc_delete(&mfc); 929 else 930 ret = ipmr_mfc_add(&mfc, sk==mroute_socket); 931 rtnl_unlock(); 932 return ret; 933 /* 934 * Control PIM assert. 935 */ 936 case MRT_ASSERT: 937 { 938 int v; 939 if(get_user(v,(int __user *)optval)) 940 return -EFAULT; 941 mroute_do_assert=(v)?1:0; 942 return 0; 943 } 944 #ifdef CONFIG_IP_PIMSM 945 case MRT_PIM: 946 { 947 int v, ret; 948 if(get_user(v,(int __user *)optval)) 949 return -EFAULT; 950 v = (v)?1:0; 951 rtnl_lock(); 952 ret = 0; 953 if (v != mroute_do_pim) { 954 mroute_do_pim = v; 955 mroute_do_assert = v; 956 #ifdef CONFIG_IP_PIMSM_V2 957 if (mroute_do_pim) 958 ret = inet_add_protocol(&pim_protocol, 959 IPPROTO_PIM); 960 else 961 ret = inet_del_protocol(&pim_protocol, 962 IPPROTO_PIM); 963 if (ret < 0) 964 ret = -EAGAIN; 965 #endif 966 } 967 rtnl_unlock(); 968 return ret; 969 } 970 #endif 971 /* 972 * Spurious command, or MRT_VERSION which you cannot 973 * set. 974 */ 975 default: 976 return -ENOPROTOOPT; 977 } 978 } 979 980 /* 981 * Getsock opt support for the multicast routing system. 982 */ 983 984 int ip_mroute_getsockopt(struct sock *sk,int optname,char __user *optval,int __user *optlen) 985 { 986 int olr; 987 int val; 988 989 if(optname!=MRT_VERSION && 990 #ifdef CONFIG_IP_PIMSM 991 optname!=MRT_PIM && 992 #endif 993 optname!=MRT_ASSERT) 994 return -ENOPROTOOPT; 995 996 if (get_user(olr, optlen)) 997 return -EFAULT; 998 999 olr = min_t(unsigned int, olr, sizeof(int)); 1000 if (olr < 0) 1001 return -EINVAL; 1002 1003 if(put_user(olr,optlen)) 1004 return -EFAULT; 1005 if(optname==MRT_VERSION) 1006 val=0x0305; 1007 #ifdef CONFIG_IP_PIMSM 1008 else if(optname==MRT_PIM) 1009 val=mroute_do_pim; 1010 #endif 1011 else 1012 val=mroute_do_assert; 1013 if(copy_to_user(optval,&val,olr)) 1014 return -EFAULT; 1015 return 0; 1016 } 1017 1018 /* 1019 * The IP multicast ioctl support routines. 1020 */ 1021 1022 int ipmr_ioctl(struct sock *sk, int cmd, void __user *arg) 1023 { 1024 struct sioc_sg_req sr; 1025 struct sioc_vif_req vr; 1026 struct vif_device *vif; 1027 struct mfc_cache *c; 1028 1029 switch(cmd) 1030 { 1031 case SIOCGETVIFCNT: 1032 if (copy_from_user(&vr,arg,sizeof(vr))) 1033 return -EFAULT; 1034 if(vr.vifi>=maxvif) 1035 return -EINVAL; 1036 read_lock(&mrt_lock); 1037 vif=&vif_table[vr.vifi]; 1038 if(VIF_EXISTS(vr.vifi)) { 1039 vr.icount=vif->pkt_in; 1040 vr.ocount=vif->pkt_out; 1041 vr.ibytes=vif->bytes_in; 1042 vr.obytes=vif->bytes_out; 1043 read_unlock(&mrt_lock); 1044 1045 if (copy_to_user(arg,&vr,sizeof(vr))) 1046 return -EFAULT; 1047 return 0; 1048 } 1049 read_unlock(&mrt_lock); 1050 return -EADDRNOTAVAIL; 1051 case SIOCGETSGCNT: 1052 if (copy_from_user(&sr,arg,sizeof(sr))) 1053 return -EFAULT; 1054 1055 read_lock(&mrt_lock); 1056 c = ipmr_cache_find(sr.src.s_addr, sr.grp.s_addr); 1057 if (c) { 1058 sr.pktcnt = c->mfc_un.res.pkt; 1059 sr.bytecnt = c->mfc_un.res.bytes; 1060 sr.wrong_if = c->mfc_un.res.wrong_if; 1061 read_unlock(&mrt_lock); 1062 1063 if (copy_to_user(arg,&sr,sizeof(sr))) 1064 return -EFAULT; 1065 return 0; 1066 } 1067 read_unlock(&mrt_lock); 1068 return -EADDRNOTAVAIL; 1069 default: 1070 return -ENOIOCTLCMD; 1071 } 1072 } 1073 1074 1075 static int ipmr_device_event(struct notifier_block *this, unsigned long event, void *ptr) 1076 { 1077 struct vif_device *v; 1078 int ct; 1079 if (event != NETDEV_UNREGISTER) 1080 return NOTIFY_DONE; 1081 v=&vif_table[0]; 1082 for(ct=0;ct<maxvif;ct++,v++) { 1083 if (v->dev==ptr) 1084 vif_delete(ct); 1085 } 1086 return NOTIFY_DONE; 1087 } 1088 1089 1090 static struct notifier_block ip_mr_notifier={ 1091 .notifier_call = ipmr_device_event, 1092 }; 1093 1094 /* 1095 * Encapsulate a packet by attaching a valid IPIP header to it. 1096 * This avoids tunnel drivers and other mess and gives us the speed so 1097 * important for multicast video. 1098 */ 1099 1100 static void ip_encap(struct sk_buff *skb, __be32 saddr, __be32 daddr) 1101 { 1102 struct iphdr *iph = (struct iphdr *)skb_push(skb,sizeof(struct iphdr)); 1103 1104 iph->version = 4; 1105 iph->tos = skb->nh.iph->tos; 1106 iph->ttl = skb->nh.iph->ttl; 1107 iph->frag_off = 0; 1108 iph->daddr = daddr; 1109 iph->saddr = saddr; 1110 iph->protocol = IPPROTO_IPIP; 1111 iph->ihl = 5; 1112 iph->tot_len = htons(skb->len); 1113 ip_select_ident(iph, skb->dst, NULL); 1114 ip_send_check(iph); 1115 1116 skb->h.ipiph = skb->nh.iph; 1117 skb->nh.iph = iph; 1118 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); 1119 nf_reset(skb); 1120 } 1121 1122 static inline int ipmr_forward_finish(struct sk_buff *skb) 1123 { 1124 struct ip_options * opt = &(IPCB(skb)->opt); 1125 1126 IP_INC_STATS_BH(IPSTATS_MIB_OUTFORWDATAGRAMS); 1127 1128 if (unlikely(opt->optlen)) 1129 ip_forward_options(skb); 1130 1131 return dst_output(skb); 1132 } 1133 1134 /* 1135 * Processing handlers for ipmr_forward 1136 */ 1137 1138 static void ipmr_queue_xmit(struct sk_buff *skb, struct mfc_cache *c, int vifi) 1139 { 1140 struct iphdr *iph = skb->nh.iph; 1141 struct vif_device *vif = &vif_table[vifi]; 1142 struct net_device *dev; 1143 struct rtable *rt; 1144 int encap = 0; 1145 1146 if (vif->dev == NULL) 1147 goto out_free; 1148 1149 #ifdef CONFIG_IP_PIMSM 1150 if (vif->flags & VIFF_REGISTER) { 1151 vif->pkt_out++; 1152 vif->bytes_out+=skb->len; 1153 ((struct net_device_stats*)netdev_priv(vif->dev))->tx_bytes += skb->len; 1154 ((struct net_device_stats*)netdev_priv(vif->dev))->tx_packets++; 1155 ipmr_cache_report(skb, vifi, IGMPMSG_WHOLEPKT); 1156 kfree_skb(skb); 1157 return; 1158 } 1159 #endif 1160 1161 if (vif->flags&VIFF_TUNNEL) { 1162 struct flowi fl = { .oif = vif->link, 1163 .nl_u = { .ip4_u = 1164 { .daddr = vif->remote, 1165 .saddr = vif->local, 1166 .tos = RT_TOS(iph->tos) } }, 1167 .proto = IPPROTO_IPIP }; 1168 if (ip_route_output_key(&rt, &fl)) 1169 goto out_free; 1170 encap = sizeof(struct iphdr); 1171 } else { 1172 struct flowi fl = { .oif = vif->link, 1173 .nl_u = { .ip4_u = 1174 { .daddr = iph->daddr, 1175 .tos = RT_TOS(iph->tos) } }, 1176 .proto = IPPROTO_IPIP }; 1177 if (ip_route_output_key(&rt, &fl)) 1178 goto out_free; 1179 } 1180 1181 dev = rt->u.dst.dev; 1182 1183 if (skb->len+encap > dst_mtu(&rt->u.dst) && (ntohs(iph->frag_off) & IP_DF)) { 1184 /* Do not fragment multicasts. Alas, IPv4 does not 1185 allow to send ICMP, so that packets will disappear 1186 to blackhole. 1187 */ 1188 1189 IP_INC_STATS_BH(IPSTATS_MIB_FRAGFAILS); 1190 ip_rt_put(rt); 1191 goto out_free; 1192 } 1193 1194 encap += LL_RESERVED_SPACE(dev) + rt->u.dst.header_len; 1195 1196 if (skb_cow(skb, encap)) { 1197 ip_rt_put(rt); 1198 goto out_free; 1199 } 1200 1201 vif->pkt_out++; 1202 vif->bytes_out+=skb->len; 1203 1204 dst_release(skb->dst); 1205 skb->dst = &rt->u.dst; 1206 iph = skb->nh.iph; 1207 ip_decrease_ttl(iph); 1208 1209 /* FIXME: forward and output firewalls used to be called here. 1210 * What do we do with netfilter? -- RR */ 1211 if (vif->flags & VIFF_TUNNEL) { 1212 ip_encap(skb, vif->local, vif->remote); 1213 /* FIXME: extra output firewall step used to be here. --RR */ 1214 ((struct ip_tunnel *)netdev_priv(vif->dev))->stat.tx_packets++; 1215 ((struct ip_tunnel *)netdev_priv(vif->dev))->stat.tx_bytes+=skb->len; 1216 } 1217 1218 IPCB(skb)->flags |= IPSKB_FORWARDED; 1219 1220 /* 1221 * RFC1584 teaches, that DVMRP/PIM router must deliver packets locally 1222 * not only before forwarding, but after forwarding on all output 1223 * interfaces. It is clear, if mrouter runs a multicasting 1224 * program, it should receive packets not depending to what interface 1225 * program is joined. 1226 * If we will not make it, the program will have to join on all 1227 * interfaces. On the other hand, multihoming host (or router, but 1228 * not mrouter) cannot join to more than one interface - it will 1229 * result in receiving multiple packets. 1230 */ 1231 NF_HOOK(PF_INET, NF_IP_FORWARD, skb, skb->dev, dev, 1232 ipmr_forward_finish); 1233 return; 1234 1235 out_free: 1236 kfree_skb(skb); 1237 return; 1238 } 1239 1240 static int ipmr_find_vif(struct net_device *dev) 1241 { 1242 int ct; 1243 for (ct=maxvif-1; ct>=0; ct--) { 1244 if (vif_table[ct].dev == dev) 1245 break; 1246 } 1247 return ct; 1248 } 1249 1250 /* "local" means that we should preserve one skb (for local delivery) */ 1251 1252 static int ip_mr_forward(struct sk_buff *skb, struct mfc_cache *cache, int local) 1253 { 1254 int psend = -1; 1255 int vif, ct; 1256 1257 vif = cache->mfc_parent; 1258 cache->mfc_un.res.pkt++; 1259 cache->mfc_un.res.bytes += skb->len; 1260 1261 /* 1262 * Wrong interface: drop packet and (maybe) send PIM assert. 1263 */ 1264 if (vif_table[vif].dev != skb->dev) { 1265 int true_vifi; 1266 1267 if (((struct rtable*)skb->dst)->fl.iif == 0) { 1268 /* It is our own packet, looped back. 1269 Very complicated situation... 1270 1271 The best workaround until routing daemons will be 1272 fixed is not to redistribute packet, if it was 1273 send through wrong interface. It means, that 1274 multicast applications WILL NOT work for 1275 (S,G), which have default multicast route pointing 1276 to wrong oif. In any case, it is not a good 1277 idea to use multicasting applications on router. 1278 */ 1279 goto dont_forward; 1280 } 1281 1282 cache->mfc_un.res.wrong_if++; 1283 true_vifi = ipmr_find_vif(skb->dev); 1284 1285 if (true_vifi >= 0 && mroute_do_assert && 1286 /* pimsm uses asserts, when switching from RPT to SPT, 1287 so that we cannot check that packet arrived on an oif. 1288 It is bad, but otherwise we would need to move pretty 1289 large chunk of pimd to kernel. Ough... --ANK 1290 */ 1291 (mroute_do_pim || cache->mfc_un.res.ttls[true_vifi] < 255) && 1292 time_after(jiffies, 1293 cache->mfc_un.res.last_assert + MFC_ASSERT_THRESH)) { 1294 cache->mfc_un.res.last_assert = jiffies; 1295 ipmr_cache_report(skb, true_vifi, IGMPMSG_WRONGVIF); 1296 } 1297 goto dont_forward; 1298 } 1299 1300 vif_table[vif].pkt_in++; 1301 vif_table[vif].bytes_in+=skb->len; 1302 1303 /* 1304 * Forward the frame 1305 */ 1306 for (ct = cache->mfc_un.res.maxvif-1; ct >= cache->mfc_un.res.minvif; ct--) { 1307 if (skb->nh.iph->ttl > cache->mfc_un.res.ttls[ct]) { 1308 if (psend != -1) { 1309 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); 1310 if (skb2) 1311 ipmr_queue_xmit(skb2, cache, psend); 1312 } 1313 psend=ct; 1314 } 1315 } 1316 if (psend != -1) { 1317 if (local) { 1318 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); 1319 if (skb2) 1320 ipmr_queue_xmit(skb2, cache, psend); 1321 } else { 1322 ipmr_queue_xmit(skb, cache, psend); 1323 return 0; 1324 } 1325 } 1326 1327 dont_forward: 1328 if (!local) 1329 kfree_skb(skb); 1330 return 0; 1331 } 1332 1333 1334 /* 1335 * Multicast packets for forwarding arrive here 1336 */ 1337 1338 int ip_mr_input(struct sk_buff *skb) 1339 { 1340 struct mfc_cache *cache; 1341 int local = ((struct rtable*)skb->dst)->rt_flags&RTCF_LOCAL; 1342 1343 /* Packet is looped back after forward, it should not be 1344 forwarded second time, but still can be delivered locally. 1345 */ 1346 if (IPCB(skb)->flags&IPSKB_FORWARDED) 1347 goto dont_forward; 1348 1349 if (!local) { 1350 if (IPCB(skb)->opt.router_alert) { 1351 if (ip_call_ra_chain(skb)) 1352 return 0; 1353 } else if (skb->nh.iph->protocol == IPPROTO_IGMP){ 1354 /* IGMPv1 (and broken IGMPv2 implementations sort of 1355 Cisco IOS <= 11.2(8)) do not put router alert 1356 option to IGMP packets destined to routable 1357 groups. It is very bad, because it means 1358 that we can forward NO IGMP messages. 1359 */ 1360 read_lock(&mrt_lock); 1361 if (mroute_socket) { 1362 nf_reset(skb); 1363 raw_rcv(mroute_socket, skb); 1364 read_unlock(&mrt_lock); 1365 return 0; 1366 } 1367 read_unlock(&mrt_lock); 1368 } 1369 } 1370 1371 read_lock(&mrt_lock); 1372 cache = ipmr_cache_find(skb->nh.iph->saddr, skb->nh.iph->daddr); 1373 1374 /* 1375 * No usable cache entry 1376 */ 1377 if (cache==NULL) { 1378 int vif; 1379 1380 if (local) { 1381 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); 1382 ip_local_deliver(skb); 1383 if (skb2 == NULL) { 1384 read_unlock(&mrt_lock); 1385 return -ENOBUFS; 1386 } 1387 skb = skb2; 1388 } 1389 1390 vif = ipmr_find_vif(skb->dev); 1391 if (vif >= 0) { 1392 int err = ipmr_cache_unresolved(vif, skb); 1393 read_unlock(&mrt_lock); 1394 1395 return err; 1396 } 1397 read_unlock(&mrt_lock); 1398 kfree_skb(skb); 1399 return -ENODEV; 1400 } 1401 1402 ip_mr_forward(skb, cache, local); 1403 1404 read_unlock(&mrt_lock); 1405 1406 if (local) 1407 return ip_local_deliver(skb); 1408 1409 return 0; 1410 1411 dont_forward: 1412 if (local) 1413 return ip_local_deliver(skb); 1414 kfree_skb(skb); 1415 return 0; 1416 } 1417 1418 #ifdef CONFIG_IP_PIMSM_V1 1419 /* 1420 * Handle IGMP messages of PIMv1 1421 */ 1422 1423 int pim_rcv_v1(struct sk_buff * skb) 1424 { 1425 struct igmphdr *pim; 1426 struct iphdr *encap; 1427 struct net_device *reg_dev = NULL; 1428 1429 if (!pskb_may_pull(skb, sizeof(*pim) + sizeof(*encap))) 1430 goto drop; 1431 1432 pim = (struct igmphdr*)skb->h.raw; 1433 1434 if (!mroute_do_pim || 1435 skb->len < sizeof(*pim) + sizeof(*encap) || 1436 pim->group != PIM_V1_VERSION || pim->code != PIM_V1_REGISTER) 1437 goto drop; 1438 1439 encap = (struct iphdr*)(skb->h.raw + sizeof(struct igmphdr)); 1440 /* 1441 Check that: 1442 a. packet is really destinted to a multicast group 1443 b. packet is not a NULL-REGISTER 1444 c. packet is not truncated 1445 */ 1446 if (!MULTICAST(encap->daddr) || 1447 encap->tot_len == 0 || 1448 ntohs(encap->tot_len) + sizeof(*pim) > skb->len) 1449 goto drop; 1450 1451 read_lock(&mrt_lock); 1452 if (reg_vif_num >= 0) 1453 reg_dev = vif_table[reg_vif_num].dev; 1454 if (reg_dev) 1455 dev_hold(reg_dev); 1456 read_unlock(&mrt_lock); 1457 1458 if (reg_dev == NULL) 1459 goto drop; 1460 1461 skb->mac.raw = skb->nh.raw; 1462 skb_pull(skb, (u8*)encap - skb->data); 1463 skb->nh.iph = (struct iphdr *)skb->data; 1464 skb->dev = reg_dev; 1465 skb->protocol = htons(ETH_P_IP); 1466 skb->ip_summed = 0; 1467 skb->pkt_type = PACKET_HOST; 1468 dst_release(skb->dst); 1469 skb->dst = NULL; 1470 ((struct net_device_stats*)netdev_priv(reg_dev))->rx_bytes += skb->len; 1471 ((struct net_device_stats*)netdev_priv(reg_dev))->rx_packets++; 1472 nf_reset(skb); 1473 netif_rx(skb); 1474 dev_put(reg_dev); 1475 return 0; 1476 drop: 1477 kfree_skb(skb); 1478 return 0; 1479 } 1480 #endif 1481 1482 #ifdef CONFIG_IP_PIMSM_V2 1483 static int pim_rcv(struct sk_buff * skb) 1484 { 1485 struct pimreghdr *pim; 1486 struct iphdr *encap; 1487 struct net_device *reg_dev = NULL; 1488 1489 if (!pskb_may_pull(skb, sizeof(*pim) + sizeof(*encap))) 1490 goto drop; 1491 1492 pim = (struct pimreghdr*)skb->h.raw; 1493 if (pim->type != ((PIM_VERSION<<4)|(PIM_REGISTER)) || 1494 (pim->flags&PIM_NULL_REGISTER) || 1495 (ip_compute_csum((void *)pim, sizeof(*pim)) != 0 && 1496 csum_fold(skb_checksum(skb, 0, skb->len, 0)))) 1497 goto drop; 1498 1499 /* check if the inner packet is destined to mcast group */ 1500 encap = (struct iphdr*)(skb->h.raw + sizeof(struct pimreghdr)); 1501 if (!MULTICAST(encap->daddr) || 1502 encap->tot_len == 0 || 1503 ntohs(encap->tot_len) + sizeof(*pim) > skb->len) 1504 goto drop; 1505 1506 read_lock(&mrt_lock); 1507 if (reg_vif_num >= 0) 1508 reg_dev = vif_table[reg_vif_num].dev; 1509 if (reg_dev) 1510 dev_hold(reg_dev); 1511 read_unlock(&mrt_lock); 1512 1513 if (reg_dev == NULL) 1514 goto drop; 1515 1516 skb->mac.raw = skb->nh.raw; 1517 skb_pull(skb, (u8*)encap - skb->data); 1518 skb->nh.iph = (struct iphdr *)skb->data; 1519 skb->dev = reg_dev; 1520 skb->protocol = htons(ETH_P_IP); 1521 skb->ip_summed = 0; 1522 skb->pkt_type = PACKET_HOST; 1523 dst_release(skb->dst); 1524 ((struct net_device_stats*)netdev_priv(reg_dev))->rx_bytes += skb->len; 1525 ((struct net_device_stats*)netdev_priv(reg_dev))->rx_packets++; 1526 skb->dst = NULL; 1527 nf_reset(skb); 1528 netif_rx(skb); 1529 dev_put(reg_dev); 1530 return 0; 1531 drop: 1532 kfree_skb(skb); 1533 return 0; 1534 } 1535 #endif 1536 1537 static int 1538 ipmr_fill_mroute(struct sk_buff *skb, struct mfc_cache *c, struct rtmsg *rtm) 1539 { 1540 int ct; 1541 struct rtnexthop *nhp; 1542 struct net_device *dev = vif_table[c->mfc_parent].dev; 1543 u8 *b = skb->tail; 1544 struct rtattr *mp_head; 1545 1546 if (dev) 1547 RTA_PUT(skb, RTA_IIF, 4, &dev->ifindex); 1548 1549 mp_head = (struct rtattr*)skb_put(skb, RTA_LENGTH(0)); 1550 1551 for (ct = c->mfc_un.res.minvif; ct < c->mfc_un.res.maxvif; ct++) { 1552 if (c->mfc_un.res.ttls[ct] < 255) { 1553 if (skb_tailroom(skb) < RTA_ALIGN(RTA_ALIGN(sizeof(*nhp)) + 4)) 1554 goto rtattr_failure; 1555 nhp = (struct rtnexthop*)skb_put(skb, RTA_ALIGN(sizeof(*nhp))); 1556 nhp->rtnh_flags = 0; 1557 nhp->rtnh_hops = c->mfc_un.res.ttls[ct]; 1558 nhp->rtnh_ifindex = vif_table[ct].dev->ifindex; 1559 nhp->rtnh_len = sizeof(*nhp); 1560 } 1561 } 1562 mp_head->rta_type = RTA_MULTIPATH; 1563 mp_head->rta_len = skb->tail - (u8*)mp_head; 1564 rtm->rtm_type = RTN_MULTICAST; 1565 return 1; 1566 1567 rtattr_failure: 1568 skb_trim(skb, b - skb->data); 1569 return -EMSGSIZE; 1570 } 1571 1572 int ipmr_get_route(struct sk_buff *skb, struct rtmsg *rtm, int nowait) 1573 { 1574 int err; 1575 struct mfc_cache *cache; 1576 struct rtable *rt = (struct rtable*)skb->dst; 1577 1578 read_lock(&mrt_lock); 1579 cache = ipmr_cache_find(rt->rt_src, rt->rt_dst); 1580 1581 if (cache==NULL) { 1582 struct sk_buff *skb2; 1583 struct net_device *dev; 1584 int vif; 1585 1586 if (nowait) { 1587 read_unlock(&mrt_lock); 1588 return -EAGAIN; 1589 } 1590 1591 dev = skb->dev; 1592 if (dev == NULL || (vif = ipmr_find_vif(dev)) < 0) { 1593 read_unlock(&mrt_lock); 1594 return -ENODEV; 1595 } 1596 skb2 = skb_clone(skb, GFP_ATOMIC); 1597 if (!skb2) { 1598 read_unlock(&mrt_lock); 1599 return -ENOMEM; 1600 } 1601 1602 skb2->nh.raw = skb_push(skb2, sizeof(struct iphdr)); 1603 skb2->nh.iph->ihl = sizeof(struct iphdr)>>2; 1604 skb2->nh.iph->saddr = rt->rt_src; 1605 skb2->nh.iph->daddr = rt->rt_dst; 1606 skb2->nh.iph->version = 0; 1607 err = ipmr_cache_unresolved(vif, skb2); 1608 read_unlock(&mrt_lock); 1609 return err; 1610 } 1611 1612 if (!nowait && (rtm->rtm_flags&RTM_F_NOTIFY)) 1613 cache->mfc_flags |= MFC_NOTIFY; 1614 err = ipmr_fill_mroute(skb, cache, rtm); 1615 read_unlock(&mrt_lock); 1616 return err; 1617 } 1618 1619 #ifdef CONFIG_PROC_FS 1620 /* 1621 * The /proc interfaces to multicast routing /proc/ip_mr_cache /proc/ip_mr_vif 1622 */ 1623 struct ipmr_vif_iter { 1624 int ct; 1625 }; 1626 1627 static struct vif_device *ipmr_vif_seq_idx(struct ipmr_vif_iter *iter, 1628 loff_t pos) 1629 { 1630 for (iter->ct = 0; iter->ct < maxvif; ++iter->ct) { 1631 if(!VIF_EXISTS(iter->ct)) 1632 continue; 1633 if (pos-- == 0) 1634 return &vif_table[iter->ct]; 1635 } 1636 return NULL; 1637 } 1638 1639 static void *ipmr_vif_seq_start(struct seq_file *seq, loff_t *pos) 1640 { 1641 read_lock(&mrt_lock); 1642 return *pos ? ipmr_vif_seq_idx(seq->private, *pos - 1) 1643 : SEQ_START_TOKEN; 1644 } 1645 1646 static void *ipmr_vif_seq_next(struct seq_file *seq, void *v, loff_t *pos) 1647 { 1648 struct ipmr_vif_iter *iter = seq->private; 1649 1650 ++*pos; 1651 if (v == SEQ_START_TOKEN) 1652 return ipmr_vif_seq_idx(iter, 0); 1653 1654 while (++iter->ct < maxvif) { 1655 if(!VIF_EXISTS(iter->ct)) 1656 continue; 1657 return &vif_table[iter->ct]; 1658 } 1659 return NULL; 1660 } 1661 1662 static void ipmr_vif_seq_stop(struct seq_file *seq, void *v) 1663 { 1664 read_unlock(&mrt_lock); 1665 } 1666 1667 static int ipmr_vif_seq_show(struct seq_file *seq, void *v) 1668 { 1669 if (v == SEQ_START_TOKEN) { 1670 seq_puts(seq, 1671 "Interface BytesIn PktsIn BytesOut PktsOut Flags Local Remote\n"); 1672 } else { 1673 const struct vif_device *vif = v; 1674 const char *name = vif->dev ? vif->dev->name : "none"; 1675 1676 seq_printf(seq, 1677 "%2Zd %-10s %8ld %7ld %8ld %7ld %05X %08X %08X\n", 1678 vif - vif_table, 1679 name, vif->bytes_in, vif->pkt_in, 1680 vif->bytes_out, vif->pkt_out, 1681 vif->flags, vif->local, vif->remote); 1682 } 1683 return 0; 1684 } 1685 1686 static struct seq_operations ipmr_vif_seq_ops = { 1687 .start = ipmr_vif_seq_start, 1688 .next = ipmr_vif_seq_next, 1689 .stop = ipmr_vif_seq_stop, 1690 .show = ipmr_vif_seq_show, 1691 }; 1692 1693 static int ipmr_vif_open(struct inode *inode, struct file *file) 1694 { 1695 struct seq_file *seq; 1696 int rc = -ENOMEM; 1697 struct ipmr_vif_iter *s = kmalloc(sizeof(*s), GFP_KERNEL); 1698 1699 if (!s) 1700 goto out; 1701 1702 rc = seq_open(file, &ipmr_vif_seq_ops); 1703 if (rc) 1704 goto out_kfree; 1705 1706 s->ct = 0; 1707 seq = file->private_data; 1708 seq->private = s; 1709 out: 1710 return rc; 1711 out_kfree: 1712 kfree(s); 1713 goto out; 1714 1715 } 1716 1717 static struct file_operations ipmr_vif_fops = { 1718 .owner = THIS_MODULE, 1719 .open = ipmr_vif_open, 1720 .read = seq_read, 1721 .llseek = seq_lseek, 1722 .release = seq_release_private, 1723 }; 1724 1725 struct ipmr_mfc_iter { 1726 struct mfc_cache **cache; 1727 int ct; 1728 }; 1729 1730 1731 static struct mfc_cache *ipmr_mfc_seq_idx(struct ipmr_mfc_iter *it, loff_t pos) 1732 { 1733 struct mfc_cache *mfc; 1734 1735 it->cache = mfc_cache_array; 1736 read_lock(&mrt_lock); 1737 for (it->ct = 0; it->ct < MFC_LINES; it->ct++) 1738 for(mfc = mfc_cache_array[it->ct]; mfc; mfc = mfc->next) 1739 if (pos-- == 0) 1740 return mfc; 1741 read_unlock(&mrt_lock); 1742 1743 it->cache = &mfc_unres_queue; 1744 spin_lock_bh(&mfc_unres_lock); 1745 for(mfc = mfc_unres_queue; mfc; mfc = mfc->next) 1746 if (pos-- == 0) 1747 return mfc; 1748 spin_unlock_bh(&mfc_unres_lock); 1749 1750 it->cache = NULL; 1751 return NULL; 1752 } 1753 1754 1755 static void *ipmr_mfc_seq_start(struct seq_file *seq, loff_t *pos) 1756 { 1757 struct ipmr_mfc_iter *it = seq->private; 1758 it->cache = NULL; 1759 it->ct = 0; 1760 return *pos ? ipmr_mfc_seq_idx(seq->private, *pos - 1) 1761 : SEQ_START_TOKEN; 1762 } 1763 1764 static void *ipmr_mfc_seq_next(struct seq_file *seq, void *v, loff_t *pos) 1765 { 1766 struct mfc_cache *mfc = v; 1767 struct ipmr_mfc_iter *it = seq->private; 1768 1769 ++*pos; 1770 1771 if (v == SEQ_START_TOKEN) 1772 return ipmr_mfc_seq_idx(seq->private, 0); 1773 1774 if (mfc->next) 1775 return mfc->next; 1776 1777 if (it->cache == &mfc_unres_queue) 1778 goto end_of_list; 1779 1780 BUG_ON(it->cache != mfc_cache_array); 1781 1782 while (++it->ct < MFC_LINES) { 1783 mfc = mfc_cache_array[it->ct]; 1784 if (mfc) 1785 return mfc; 1786 } 1787 1788 /* exhausted cache_array, show unresolved */ 1789 read_unlock(&mrt_lock); 1790 it->cache = &mfc_unres_queue; 1791 it->ct = 0; 1792 1793 spin_lock_bh(&mfc_unres_lock); 1794 mfc = mfc_unres_queue; 1795 if (mfc) 1796 return mfc; 1797 1798 end_of_list: 1799 spin_unlock_bh(&mfc_unres_lock); 1800 it->cache = NULL; 1801 1802 return NULL; 1803 } 1804 1805 static void ipmr_mfc_seq_stop(struct seq_file *seq, void *v) 1806 { 1807 struct ipmr_mfc_iter *it = seq->private; 1808 1809 if (it->cache == &mfc_unres_queue) 1810 spin_unlock_bh(&mfc_unres_lock); 1811 else if (it->cache == mfc_cache_array) 1812 read_unlock(&mrt_lock); 1813 } 1814 1815 static int ipmr_mfc_seq_show(struct seq_file *seq, void *v) 1816 { 1817 int n; 1818 1819 if (v == SEQ_START_TOKEN) { 1820 seq_puts(seq, 1821 "Group Origin Iif Pkts Bytes Wrong Oifs\n"); 1822 } else { 1823 const struct mfc_cache *mfc = v; 1824 const struct ipmr_mfc_iter *it = seq->private; 1825 1826 seq_printf(seq, "%08lX %08lX %-3d %8ld %8ld %8ld", 1827 (unsigned long) mfc->mfc_mcastgrp, 1828 (unsigned long) mfc->mfc_origin, 1829 mfc->mfc_parent, 1830 mfc->mfc_un.res.pkt, 1831 mfc->mfc_un.res.bytes, 1832 mfc->mfc_un.res.wrong_if); 1833 1834 if (it->cache != &mfc_unres_queue) { 1835 for(n = mfc->mfc_un.res.minvif; 1836 n < mfc->mfc_un.res.maxvif; n++ ) { 1837 if(VIF_EXISTS(n) 1838 && mfc->mfc_un.res.ttls[n] < 255) 1839 seq_printf(seq, 1840 " %2d:%-3d", 1841 n, mfc->mfc_un.res.ttls[n]); 1842 } 1843 } 1844 seq_putc(seq, '\n'); 1845 } 1846 return 0; 1847 } 1848 1849 static struct seq_operations ipmr_mfc_seq_ops = { 1850 .start = ipmr_mfc_seq_start, 1851 .next = ipmr_mfc_seq_next, 1852 .stop = ipmr_mfc_seq_stop, 1853 .show = ipmr_mfc_seq_show, 1854 }; 1855 1856 static int ipmr_mfc_open(struct inode *inode, struct file *file) 1857 { 1858 struct seq_file *seq; 1859 int rc = -ENOMEM; 1860 struct ipmr_mfc_iter *s = kmalloc(sizeof(*s), GFP_KERNEL); 1861 1862 if (!s) 1863 goto out; 1864 1865 rc = seq_open(file, &ipmr_mfc_seq_ops); 1866 if (rc) 1867 goto out_kfree; 1868 1869 seq = file->private_data; 1870 seq->private = s; 1871 out: 1872 return rc; 1873 out_kfree: 1874 kfree(s); 1875 goto out; 1876 1877 } 1878 1879 static struct file_operations ipmr_mfc_fops = { 1880 .owner = THIS_MODULE, 1881 .open = ipmr_mfc_open, 1882 .read = seq_read, 1883 .llseek = seq_lseek, 1884 .release = seq_release_private, 1885 }; 1886 #endif 1887 1888 #ifdef CONFIG_IP_PIMSM_V2 1889 static struct net_protocol pim_protocol = { 1890 .handler = pim_rcv, 1891 }; 1892 #endif 1893 1894 1895 /* 1896 * Setup for IP multicast routing 1897 */ 1898 1899 void __init ip_mr_init(void) 1900 { 1901 mrt_cachep = kmem_cache_create("ip_mrt_cache", 1902 sizeof(struct mfc_cache), 1903 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, 1904 NULL, NULL); 1905 init_timer(&ipmr_expire_timer); 1906 ipmr_expire_timer.function=ipmr_expire_process; 1907 register_netdevice_notifier(&ip_mr_notifier); 1908 #ifdef CONFIG_PROC_FS 1909 proc_net_fops_create("ip_mr_vif", 0, &ipmr_vif_fops); 1910 proc_net_fops_create("ip_mr_cache", 0, &ipmr_mfc_fops); 1911 #endif 1912 } 1913