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 <linux/config.h> 32 #include <asm/system.h> 33 #include <asm/uaccess.h> 34 #include <linux/types.h> 35 #include <linux/sched.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 <net/ip.h> 53 #include <net/protocol.h> 54 #include <linux/skbuff.h> 55 #include <net/sock.h> 56 #include <net/icmp.h> 57 #include <net/udp.h> 58 #include <net/raw.h> 59 #include <linux/notifier.h> 60 #include <linux/if_arp.h> 61 #include <linux/netfilter_ipv4.h> 62 #include <net/ipip.h> 63 #include <net/checksum.h> 64 65 #if defined(CONFIG_IP_PIMSM_V1) || defined(CONFIG_IP_PIMSM_V2) 66 #define CONFIG_IP_PIMSM 1 67 #endif 68 69 static struct sock *mroute_socket; 70 71 72 /* Big lock, protecting vif table, mrt cache and mroute socket state. 73 Note that the changes are semaphored via rtnl_lock. 74 */ 75 76 static DEFINE_RWLOCK(mrt_lock); 77 78 /* 79 * Multicast router control variables 80 */ 81 82 static struct vif_device vif_table[MAXVIFS]; /* Devices */ 83 static int maxvif; 84 85 #define VIF_EXISTS(idx) (vif_table[idx].dev != NULL) 86 87 static int mroute_do_assert; /* Set in PIM assert */ 88 static int mroute_do_pim; 89 90 static struct mfc_cache *mfc_cache_array[MFC_LINES]; /* Forwarding cache */ 91 92 static struct mfc_cache *mfc_unres_queue; /* Queue of unresolved entries */ 93 static atomic_t cache_resolve_queue_len; /* Size of unresolved */ 94 95 /* Special spinlock for queue of unresolved entries */ 96 static DEFINE_SPINLOCK(mfc_unres_lock); 97 98 /* We return to original Alan's scheme. Hash table of resolved 99 entries is changed only in process context and protected 100 with weak lock mrt_lock. Queue of unresolved entries is protected 101 with strong spinlock mfc_unres_lock. 102 103 In this case data path is free of exclusive locks at all. 104 */ 105 106 static kmem_cache_t *mrt_cachep __read_mostly; 107 108 static int ip_mr_forward(struct sk_buff *skb, struct mfc_cache *cache, int local); 109 static int ipmr_cache_report(struct sk_buff *pkt, vifi_t vifi, int assert); 110 static int ipmr_fill_mroute(struct sk_buff *skb, struct mfc_cache *c, struct rtmsg *rtm); 111 112 #ifdef CONFIG_IP_PIMSM_V2 113 static struct net_protocol pim_protocol; 114 #endif 115 116 static struct timer_list ipmr_expire_timer; 117 118 /* Service routines creating virtual interfaces: DVMRP tunnels and PIMREG */ 119 120 static 121 struct net_device *ipmr_new_tunnel(struct vifctl *v) 122 { 123 struct net_device *dev; 124 125 dev = __dev_get_by_name("tunl0"); 126 127 if (dev) { 128 int err; 129 struct ifreq ifr; 130 mm_segment_t oldfs; 131 struct ip_tunnel_parm p; 132 struct in_device *in_dev; 133 134 memset(&p, 0, sizeof(p)); 135 p.iph.daddr = v->vifc_rmt_addr.s_addr; 136 p.iph.saddr = v->vifc_lcl_addr.s_addr; 137 p.iph.version = 4; 138 p.iph.ihl = 5; 139 p.iph.protocol = IPPROTO_IPIP; 140 sprintf(p.name, "dvmrp%d", v->vifc_vifi); 141 ifr.ifr_ifru.ifru_data = (void*)&p; 142 143 oldfs = get_fs(); set_fs(KERNEL_DS); 144 err = dev->do_ioctl(dev, &ifr, SIOCADDTUNNEL); 145 set_fs(oldfs); 146 147 dev = NULL; 148 149 if (err == 0 && (dev = __dev_get_by_name(p.name)) != NULL) { 150 dev->flags |= IFF_MULTICAST; 151 152 in_dev = __in_dev_get_rtnl(dev); 153 if (in_dev == NULL && (in_dev = inetdev_init(dev)) == NULL) 154 goto failure; 155 in_dev->cnf.rp_filter = 0; 156 157 if (dev_open(dev)) 158 goto failure; 159 } 160 } 161 return dev; 162 163 failure: 164 /* allow the register to be completed before unregistering. */ 165 rtnl_unlock(); 166 rtnl_lock(); 167 168 unregister_netdevice(dev); 169 return NULL; 170 } 171 172 #ifdef CONFIG_IP_PIMSM 173 174 static int reg_vif_num = -1; 175 176 static int reg_vif_xmit(struct sk_buff *skb, struct net_device *dev) 177 { 178 read_lock(&mrt_lock); 179 ((struct net_device_stats*)dev->priv)->tx_bytes += skb->len; 180 ((struct net_device_stats*)dev->priv)->tx_packets++; 181 ipmr_cache_report(skb, reg_vif_num, IGMPMSG_WHOLEPKT); 182 read_unlock(&mrt_lock); 183 kfree_skb(skb); 184 return 0; 185 } 186 187 static struct net_device_stats *reg_vif_get_stats(struct net_device *dev) 188 { 189 return (struct net_device_stats*)dev->priv; 190 } 191 192 static void reg_vif_setup(struct net_device *dev) 193 { 194 dev->type = ARPHRD_PIMREG; 195 dev->mtu = 1500 - sizeof(struct iphdr) - 8; 196 dev->flags = IFF_NOARP; 197 dev->hard_start_xmit = reg_vif_xmit; 198 dev->get_stats = reg_vif_get_stats; 199 dev->destructor = free_netdev; 200 } 201 202 static struct net_device *ipmr_reg_vif(void) 203 { 204 struct net_device *dev; 205 struct in_device *in_dev; 206 207 dev = alloc_netdev(sizeof(struct net_device_stats), "pimreg", 208 reg_vif_setup); 209 210 if (dev == NULL) 211 return NULL; 212 213 if (register_netdevice(dev)) { 214 free_netdev(dev); 215 return NULL; 216 } 217 dev->iflink = 0; 218 219 if ((in_dev = inetdev_init(dev)) == NULL) 220 goto failure; 221 222 in_dev->cnf.rp_filter = 0; 223 224 if (dev_open(dev)) 225 goto failure; 226 227 return dev; 228 229 failure: 230 /* allow the register to be completed before unregistering. */ 231 rtnl_unlock(); 232 rtnl_lock(); 233 234 unregister_netdevice(dev); 235 return NULL; 236 } 237 #endif 238 239 /* 240 * Delete a VIF entry 241 */ 242 243 static int vif_delete(int vifi) 244 { 245 struct vif_device *v; 246 struct net_device *dev; 247 struct in_device *in_dev; 248 249 if (vifi < 0 || vifi >= maxvif) 250 return -EADDRNOTAVAIL; 251 252 v = &vif_table[vifi]; 253 254 write_lock_bh(&mrt_lock); 255 dev = v->dev; 256 v->dev = NULL; 257 258 if (!dev) { 259 write_unlock_bh(&mrt_lock); 260 return -EADDRNOTAVAIL; 261 } 262 263 #ifdef CONFIG_IP_PIMSM 264 if (vifi == reg_vif_num) 265 reg_vif_num = -1; 266 #endif 267 268 if (vifi+1 == maxvif) { 269 int tmp; 270 for (tmp=vifi-1; tmp>=0; tmp--) { 271 if (VIF_EXISTS(tmp)) 272 break; 273 } 274 maxvif = tmp+1; 275 } 276 277 write_unlock_bh(&mrt_lock); 278 279 dev_set_allmulti(dev, -1); 280 281 if ((in_dev = __in_dev_get_rtnl(dev)) != NULL) { 282 in_dev->cnf.mc_forwarding--; 283 ip_rt_multicast_event(in_dev); 284 } 285 286 if (v->flags&(VIFF_TUNNEL|VIFF_REGISTER)) 287 unregister_netdevice(dev); 288 289 dev_put(dev); 290 return 0; 291 } 292 293 /* Destroy an unresolved cache entry, killing queued skbs 294 and reporting error to netlink readers. 295 */ 296 297 static void ipmr_destroy_unres(struct mfc_cache *c) 298 { 299 struct sk_buff *skb; 300 struct nlmsgerr *e; 301 302 atomic_dec(&cache_resolve_queue_len); 303 304 while((skb=skb_dequeue(&c->mfc_un.unres.unresolved))) { 305 if (skb->nh.iph->version == 0) { 306 struct nlmsghdr *nlh = (struct nlmsghdr *)skb_pull(skb, sizeof(struct iphdr)); 307 nlh->nlmsg_type = NLMSG_ERROR; 308 nlh->nlmsg_len = NLMSG_LENGTH(sizeof(struct nlmsgerr)); 309 skb_trim(skb, nlh->nlmsg_len); 310 e = NLMSG_DATA(nlh); 311 e->error = -ETIMEDOUT; 312 memset(&e->msg, 0, sizeof(e->msg)); 313 netlink_unicast(rtnl, skb, NETLINK_CB(skb).dst_pid, MSG_DONTWAIT); 314 } else 315 kfree_skb(skb); 316 } 317 318 kmem_cache_free(mrt_cachep, c); 319 } 320 321 322 /* Single timer process for all the unresolved queue. */ 323 324 static void ipmr_expire_process(unsigned long dummy) 325 { 326 unsigned long now; 327 unsigned long expires; 328 struct mfc_cache *c, **cp; 329 330 if (!spin_trylock(&mfc_unres_lock)) { 331 mod_timer(&ipmr_expire_timer, jiffies+HZ/10); 332 return; 333 } 334 335 if (atomic_read(&cache_resolve_queue_len) == 0) 336 goto out; 337 338 now = jiffies; 339 expires = 10*HZ; 340 cp = &mfc_unres_queue; 341 342 while ((c=*cp) != NULL) { 343 if (time_after(c->mfc_un.unres.expires, now)) { 344 unsigned long interval = c->mfc_un.unres.expires - now; 345 if (interval < expires) 346 expires = interval; 347 cp = &c->next; 348 continue; 349 } 350 351 *cp = c->next; 352 353 ipmr_destroy_unres(c); 354 } 355 356 if (atomic_read(&cache_resolve_queue_len)) 357 mod_timer(&ipmr_expire_timer, jiffies + expires); 358 359 out: 360 spin_unlock(&mfc_unres_lock); 361 } 362 363 /* Fill oifs list. It is called under write locked mrt_lock. */ 364 365 static void ipmr_update_thresholds(struct mfc_cache *cache, unsigned char *ttls) 366 { 367 int vifi; 368 369 cache->mfc_un.res.minvif = MAXVIFS; 370 cache->mfc_un.res.maxvif = 0; 371 memset(cache->mfc_un.res.ttls, 255, MAXVIFS); 372 373 for (vifi=0; vifi<maxvif; vifi++) { 374 if (VIF_EXISTS(vifi) && ttls[vifi] && ttls[vifi] < 255) { 375 cache->mfc_un.res.ttls[vifi] = ttls[vifi]; 376 if (cache->mfc_un.res.minvif > vifi) 377 cache->mfc_un.res.minvif = vifi; 378 if (cache->mfc_un.res.maxvif <= vifi) 379 cache->mfc_un.res.maxvif = vifi + 1; 380 } 381 } 382 } 383 384 static int vif_add(struct vifctl *vifc, int mrtsock) 385 { 386 int vifi = vifc->vifc_vifi; 387 struct vif_device *v = &vif_table[vifi]; 388 struct net_device *dev; 389 struct in_device *in_dev; 390 391 /* Is vif busy ? */ 392 if (VIF_EXISTS(vifi)) 393 return -EADDRINUSE; 394 395 switch (vifc->vifc_flags) { 396 #ifdef CONFIG_IP_PIMSM 397 case VIFF_REGISTER: 398 /* 399 * Special Purpose VIF in PIM 400 * All the packets will be sent to the daemon 401 */ 402 if (reg_vif_num >= 0) 403 return -EADDRINUSE; 404 dev = ipmr_reg_vif(); 405 if (!dev) 406 return -ENOBUFS; 407 break; 408 #endif 409 case VIFF_TUNNEL: 410 dev = ipmr_new_tunnel(vifc); 411 if (!dev) 412 return -ENOBUFS; 413 break; 414 case 0: 415 dev=ip_dev_find(vifc->vifc_lcl_addr.s_addr); 416 if (!dev) 417 return -EADDRNOTAVAIL; 418 __dev_put(dev); 419 break; 420 default: 421 return -EINVAL; 422 } 423 424 if ((in_dev = __in_dev_get_rtnl(dev)) == NULL) 425 return -EADDRNOTAVAIL; 426 in_dev->cnf.mc_forwarding++; 427 dev_set_allmulti(dev, +1); 428 ip_rt_multicast_event(in_dev); 429 430 /* 431 * Fill in the VIF structures 432 */ 433 v->rate_limit=vifc->vifc_rate_limit; 434 v->local=vifc->vifc_lcl_addr.s_addr; 435 v->remote=vifc->vifc_rmt_addr.s_addr; 436 v->flags=vifc->vifc_flags; 437 if (!mrtsock) 438 v->flags |= VIFF_STATIC; 439 v->threshold=vifc->vifc_threshold; 440 v->bytes_in = 0; 441 v->bytes_out = 0; 442 v->pkt_in = 0; 443 v->pkt_out = 0; 444 v->link = dev->ifindex; 445 if (v->flags&(VIFF_TUNNEL|VIFF_REGISTER)) 446 v->link = dev->iflink; 447 448 /* And finish update writing critical data */ 449 write_lock_bh(&mrt_lock); 450 dev_hold(dev); 451 v->dev=dev; 452 #ifdef CONFIG_IP_PIMSM 453 if (v->flags&VIFF_REGISTER) 454 reg_vif_num = vifi; 455 #endif 456 if (vifi+1 > maxvif) 457 maxvif = vifi+1; 458 write_unlock_bh(&mrt_lock); 459 return 0; 460 } 461 462 static struct mfc_cache *ipmr_cache_find(__u32 origin, __u32 mcastgrp) 463 { 464 int line=MFC_HASH(mcastgrp,origin); 465 struct mfc_cache *c; 466 467 for (c=mfc_cache_array[line]; c; c = c->next) { 468 if (c->mfc_origin==origin && c->mfc_mcastgrp==mcastgrp) 469 break; 470 } 471 return c; 472 } 473 474 /* 475 * Allocate a multicast cache entry 476 */ 477 static struct mfc_cache *ipmr_cache_alloc(void) 478 { 479 struct mfc_cache *c=kmem_cache_alloc(mrt_cachep, GFP_KERNEL); 480 if(c==NULL) 481 return NULL; 482 memset(c, 0, sizeof(*c)); 483 c->mfc_un.res.minvif = MAXVIFS; 484 return c; 485 } 486 487 static struct mfc_cache *ipmr_cache_alloc_unres(void) 488 { 489 struct mfc_cache *c=kmem_cache_alloc(mrt_cachep, GFP_ATOMIC); 490 if(c==NULL) 491 return NULL; 492 memset(c, 0, sizeof(*c)); 493 skb_queue_head_init(&c->mfc_un.unres.unresolved); 494 c->mfc_un.unres.expires = jiffies + 10*HZ; 495 return c; 496 } 497 498 /* 499 * A cache entry has gone into a resolved state from queued 500 */ 501 502 static void ipmr_cache_resolve(struct mfc_cache *uc, struct mfc_cache *c) 503 { 504 struct sk_buff *skb; 505 struct nlmsgerr *e; 506 507 /* 508 * Play the pending entries through our router 509 */ 510 511 while((skb=__skb_dequeue(&uc->mfc_un.unres.unresolved))) { 512 if (skb->nh.iph->version == 0) { 513 int err; 514 struct nlmsghdr *nlh = (struct nlmsghdr *)skb_pull(skb, sizeof(struct iphdr)); 515 516 if (ipmr_fill_mroute(skb, c, NLMSG_DATA(nlh)) > 0) { 517 nlh->nlmsg_len = skb->tail - (u8*)nlh; 518 } else { 519 nlh->nlmsg_type = NLMSG_ERROR; 520 nlh->nlmsg_len = NLMSG_LENGTH(sizeof(struct nlmsgerr)); 521 skb_trim(skb, nlh->nlmsg_len); 522 e = NLMSG_DATA(nlh); 523 e->error = -EMSGSIZE; 524 memset(&e->msg, 0, sizeof(e->msg)); 525 } 526 err = netlink_unicast(rtnl, skb, NETLINK_CB(skb).dst_pid, MSG_DONTWAIT); 527 } else 528 ip_mr_forward(skb, c, 0); 529 } 530 } 531 532 /* 533 * Bounce a cache query up to mrouted. We could use netlink for this but mrouted 534 * expects the following bizarre scheme. 535 * 536 * Called under mrt_lock. 537 */ 538 539 static int ipmr_cache_report(struct sk_buff *pkt, vifi_t vifi, int assert) 540 { 541 struct sk_buff *skb; 542 int ihl = pkt->nh.iph->ihl<<2; 543 struct igmphdr *igmp; 544 struct igmpmsg *msg; 545 int ret; 546 547 #ifdef CONFIG_IP_PIMSM 548 if (assert == IGMPMSG_WHOLEPKT) 549 skb = skb_realloc_headroom(pkt, sizeof(struct iphdr)); 550 else 551 #endif 552 skb = alloc_skb(128, GFP_ATOMIC); 553 554 if(!skb) 555 return -ENOBUFS; 556 557 #ifdef CONFIG_IP_PIMSM 558 if (assert == IGMPMSG_WHOLEPKT) { 559 /* Ugly, but we have no choice with this interface. 560 Duplicate old header, fix ihl, length etc. 561 And all this only to mangle msg->im_msgtype and 562 to set msg->im_mbz to "mbz" :-) 563 */ 564 msg = (struct igmpmsg*)skb_push(skb, sizeof(struct iphdr)); 565 skb->nh.raw = skb->h.raw = (u8*)msg; 566 memcpy(msg, pkt->nh.raw, sizeof(struct iphdr)); 567 msg->im_msgtype = IGMPMSG_WHOLEPKT; 568 msg->im_mbz = 0; 569 msg->im_vif = reg_vif_num; 570 skb->nh.iph->ihl = sizeof(struct iphdr) >> 2; 571 skb->nh.iph->tot_len = htons(ntohs(pkt->nh.iph->tot_len) + sizeof(struct iphdr)); 572 } else 573 #endif 574 { 575 576 /* 577 * Copy the IP header 578 */ 579 580 skb->nh.iph = (struct iphdr *)skb_put(skb, ihl); 581 memcpy(skb->data,pkt->data,ihl); 582 skb->nh.iph->protocol = 0; /* Flag to the kernel this is a route add */ 583 msg = (struct igmpmsg*)skb->nh.iph; 584 msg->im_vif = vifi; 585 skb->dst = dst_clone(pkt->dst); 586 587 /* 588 * Add our header 589 */ 590 591 igmp=(struct igmphdr *)skb_put(skb,sizeof(struct igmphdr)); 592 igmp->type = 593 msg->im_msgtype = assert; 594 igmp->code = 0; 595 skb->nh.iph->tot_len=htons(skb->len); /* Fix the length */ 596 skb->h.raw = skb->nh.raw; 597 } 598 599 if (mroute_socket == NULL) { 600 kfree_skb(skb); 601 return -EINVAL; 602 } 603 604 /* 605 * Deliver to mrouted 606 */ 607 if ((ret=sock_queue_rcv_skb(mroute_socket,skb))<0) { 608 if (net_ratelimit()) 609 printk(KERN_WARNING "mroute: pending queue full, dropping entries.\n"); 610 kfree_skb(skb); 611 } 612 613 return ret; 614 } 615 616 /* 617 * Queue a packet for resolution. It gets locked cache entry! 618 */ 619 620 static int 621 ipmr_cache_unresolved(vifi_t vifi, struct sk_buff *skb) 622 { 623 int err; 624 struct mfc_cache *c; 625 626 spin_lock_bh(&mfc_unres_lock); 627 for (c=mfc_unres_queue; c; c=c->next) { 628 if (c->mfc_mcastgrp == skb->nh.iph->daddr && 629 c->mfc_origin == skb->nh.iph->saddr) 630 break; 631 } 632 633 if (c == NULL) { 634 /* 635 * Create a new entry if allowable 636 */ 637 638 if (atomic_read(&cache_resolve_queue_len)>=10 || 639 (c=ipmr_cache_alloc_unres())==NULL) { 640 spin_unlock_bh(&mfc_unres_lock); 641 642 kfree_skb(skb); 643 return -ENOBUFS; 644 } 645 646 /* 647 * Fill in the new cache entry 648 */ 649 c->mfc_parent=-1; 650 c->mfc_origin=skb->nh.iph->saddr; 651 c->mfc_mcastgrp=skb->nh.iph->daddr; 652 653 /* 654 * Reflect first query at mrouted. 655 */ 656 if ((err = ipmr_cache_report(skb, vifi, IGMPMSG_NOCACHE))<0) { 657 /* If the report failed throw the cache entry 658 out - Brad Parker 659 */ 660 spin_unlock_bh(&mfc_unres_lock); 661 662 kmem_cache_free(mrt_cachep, c); 663 kfree_skb(skb); 664 return err; 665 } 666 667 atomic_inc(&cache_resolve_queue_len); 668 c->next = mfc_unres_queue; 669 mfc_unres_queue = c; 670 671 mod_timer(&ipmr_expire_timer, c->mfc_un.unres.expires); 672 } 673 674 /* 675 * See if we can append the packet 676 */ 677 if (c->mfc_un.unres.unresolved.qlen>3) { 678 kfree_skb(skb); 679 err = -ENOBUFS; 680 } else { 681 skb_queue_tail(&c->mfc_un.unres.unresolved,skb); 682 err = 0; 683 } 684 685 spin_unlock_bh(&mfc_unres_lock); 686 return err; 687 } 688 689 /* 690 * MFC cache manipulation by user space mroute daemon 691 */ 692 693 static int ipmr_mfc_delete(struct mfcctl *mfc) 694 { 695 int line; 696 struct mfc_cache *c, **cp; 697 698 line=MFC_HASH(mfc->mfcc_mcastgrp.s_addr, mfc->mfcc_origin.s_addr); 699 700 for (cp=&mfc_cache_array[line]; (c=*cp) != NULL; cp = &c->next) { 701 if (c->mfc_origin == mfc->mfcc_origin.s_addr && 702 c->mfc_mcastgrp == mfc->mfcc_mcastgrp.s_addr) { 703 write_lock_bh(&mrt_lock); 704 *cp = c->next; 705 write_unlock_bh(&mrt_lock); 706 707 kmem_cache_free(mrt_cachep, c); 708 return 0; 709 } 710 } 711 return -ENOENT; 712 } 713 714 static int ipmr_mfc_add(struct mfcctl *mfc, int mrtsock) 715 { 716 int line; 717 struct mfc_cache *uc, *c, **cp; 718 719 line=MFC_HASH(mfc->mfcc_mcastgrp.s_addr, mfc->mfcc_origin.s_addr); 720 721 for (cp=&mfc_cache_array[line]; (c=*cp) != NULL; cp = &c->next) { 722 if (c->mfc_origin == mfc->mfcc_origin.s_addr && 723 c->mfc_mcastgrp == mfc->mfcc_mcastgrp.s_addr) 724 break; 725 } 726 727 if (c != NULL) { 728 write_lock_bh(&mrt_lock); 729 c->mfc_parent = mfc->mfcc_parent; 730 ipmr_update_thresholds(c, mfc->mfcc_ttls); 731 if (!mrtsock) 732 c->mfc_flags |= MFC_STATIC; 733 write_unlock_bh(&mrt_lock); 734 return 0; 735 } 736 737 if(!MULTICAST(mfc->mfcc_mcastgrp.s_addr)) 738 return -EINVAL; 739 740 c=ipmr_cache_alloc(); 741 if (c==NULL) 742 return -ENOMEM; 743 744 c->mfc_origin=mfc->mfcc_origin.s_addr; 745 c->mfc_mcastgrp=mfc->mfcc_mcastgrp.s_addr; 746 c->mfc_parent=mfc->mfcc_parent; 747 ipmr_update_thresholds(c, mfc->mfcc_ttls); 748 if (!mrtsock) 749 c->mfc_flags |= MFC_STATIC; 750 751 write_lock_bh(&mrt_lock); 752 c->next = mfc_cache_array[line]; 753 mfc_cache_array[line] = c; 754 write_unlock_bh(&mrt_lock); 755 756 /* 757 * Check to see if we resolved a queued list. If so we 758 * need to send on the frames and tidy up. 759 */ 760 spin_lock_bh(&mfc_unres_lock); 761 for (cp = &mfc_unres_queue; (uc=*cp) != NULL; 762 cp = &uc->next) { 763 if (uc->mfc_origin == c->mfc_origin && 764 uc->mfc_mcastgrp == c->mfc_mcastgrp) { 765 *cp = uc->next; 766 if (atomic_dec_and_test(&cache_resolve_queue_len)) 767 del_timer(&ipmr_expire_timer); 768 break; 769 } 770 } 771 spin_unlock_bh(&mfc_unres_lock); 772 773 if (uc) { 774 ipmr_cache_resolve(uc, c); 775 kmem_cache_free(mrt_cachep, uc); 776 } 777 return 0; 778 } 779 780 /* 781 * Close the multicast socket, and clear the vif tables etc 782 */ 783 784 static void mroute_clean_tables(struct sock *sk) 785 { 786 int i; 787 788 /* 789 * Shut down all active vif entries 790 */ 791 for(i=0; i<maxvif; i++) { 792 if (!(vif_table[i].flags&VIFF_STATIC)) 793 vif_delete(i); 794 } 795 796 /* 797 * Wipe the cache 798 */ 799 for (i=0;i<MFC_LINES;i++) { 800 struct mfc_cache *c, **cp; 801 802 cp = &mfc_cache_array[i]; 803 while ((c = *cp) != NULL) { 804 if (c->mfc_flags&MFC_STATIC) { 805 cp = &c->next; 806 continue; 807 } 808 write_lock_bh(&mrt_lock); 809 *cp = c->next; 810 write_unlock_bh(&mrt_lock); 811 812 kmem_cache_free(mrt_cachep, c); 813 } 814 } 815 816 if (atomic_read(&cache_resolve_queue_len) != 0) { 817 struct mfc_cache *c; 818 819 spin_lock_bh(&mfc_unres_lock); 820 while (mfc_unres_queue != NULL) { 821 c = mfc_unres_queue; 822 mfc_unres_queue = c->next; 823 spin_unlock_bh(&mfc_unres_lock); 824 825 ipmr_destroy_unres(c); 826 827 spin_lock_bh(&mfc_unres_lock); 828 } 829 spin_unlock_bh(&mfc_unres_lock); 830 } 831 } 832 833 static void mrtsock_destruct(struct sock *sk) 834 { 835 rtnl_lock(); 836 if (sk == mroute_socket) { 837 ipv4_devconf.mc_forwarding--; 838 839 write_lock_bh(&mrt_lock); 840 mroute_socket=NULL; 841 write_unlock_bh(&mrt_lock); 842 843 mroute_clean_tables(sk); 844 } 845 rtnl_unlock(); 846 } 847 848 /* 849 * Socket options and virtual interface manipulation. The whole 850 * virtual interface system is a complete heap, but unfortunately 851 * that's how BSD mrouted happens to think. Maybe one day with a proper 852 * MOSPF/PIM router set up we can clean this up. 853 */ 854 855 int ip_mroute_setsockopt(struct sock *sk,int optname,char __user *optval,int optlen) 856 { 857 int ret; 858 struct vifctl vif; 859 struct mfcctl mfc; 860 861 if(optname!=MRT_INIT) 862 { 863 if(sk!=mroute_socket && !capable(CAP_NET_ADMIN)) 864 return -EACCES; 865 } 866 867 switch(optname) 868 { 869 case MRT_INIT: 870 if (sk->sk_type != SOCK_RAW || 871 inet_sk(sk)->num != IPPROTO_IGMP) 872 return -EOPNOTSUPP; 873 if(optlen!=sizeof(int)) 874 return -ENOPROTOOPT; 875 876 rtnl_lock(); 877 if (mroute_socket) { 878 rtnl_unlock(); 879 return -EADDRINUSE; 880 } 881 882 ret = ip_ra_control(sk, 1, mrtsock_destruct); 883 if (ret == 0) { 884 write_lock_bh(&mrt_lock); 885 mroute_socket=sk; 886 write_unlock_bh(&mrt_lock); 887 888 ipv4_devconf.mc_forwarding++; 889 } 890 rtnl_unlock(); 891 return ret; 892 case MRT_DONE: 893 if (sk!=mroute_socket) 894 return -EACCES; 895 return ip_ra_control(sk, 0, NULL); 896 case MRT_ADD_VIF: 897 case MRT_DEL_VIF: 898 if(optlen!=sizeof(vif)) 899 return -EINVAL; 900 if (copy_from_user(&vif,optval,sizeof(vif))) 901 return -EFAULT; 902 if(vif.vifc_vifi >= MAXVIFS) 903 return -ENFILE; 904 rtnl_lock(); 905 if (optname==MRT_ADD_VIF) { 906 ret = vif_add(&vif, sk==mroute_socket); 907 } else { 908 ret = vif_delete(vif.vifc_vifi); 909 } 910 rtnl_unlock(); 911 return ret; 912 913 /* 914 * Manipulate the forwarding caches. These live 915 * in a sort of kernel/user symbiosis. 916 */ 917 case MRT_ADD_MFC: 918 case MRT_DEL_MFC: 919 if(optlen!=sizeof(mfc)) 920 return -EINVAL; 921 if (copy_from_user(&mfc,optval, sizeof(mfc))) 922 return -EFAULT; 923 rtnl_lock(); 924 if (optname==MRT_DEL_MFC) 925 ret = ipmr_mfc_delete(&mfc); 926 else 927 ret = ipmr_mfc_add(&mfc, sk==mroute_socket); 928 rtnl_unlock(); 929 return ret; 930 /* 931 * Control PIM assert. 932 */ 933 case MRT_ASSERT: 934 { 935 int v; 936 if(get_user(v,(int __user *)optval)) 937 return -EFAULT; 938 mroute_do_assert=(v)?1:0; 939 return 0; 940 } 941 #ifdef CONFIG_IP_PIMSM 942 case MRT_PIM: 943 { 944 int v, ret; 945 if(get_user(v,(int __user *)optval)) 946 return -EFAULT; 947 v = (v)?1:0; 948 rtnl_lock(); 949 ret = 0; 950 if (v != mroute_do_pim) { 951 mroute_do_pim = v; 952 mroute_do_assert = v; 953 #ifdef CONFIG_IP_PIMSM_V2 954 if (mroute_do_pim) 955 ret = inet_add_protocol(&pim_protocol, 956 IPPROTO_PIM); 957 else 958 ret = inet_del_protocol(&pim_protocol, 959 IPPROTO_PIM); 960 if (ret < 0) 961 ret = -EAGAIN; 962 #endif 963 } 964 rtnl_unlock(); 965 return ret; 966 } 967 #endif 968 /* 969 * Spurious command, or MRT_VERSION which you cannot 970 * set. 971 */ 972 default: 973 return -ENOPROTOOPT; 974 } 975 } 976 977 /* 978 * Getsock opt support for the multicast routing system. 979 */ 980 981 int ip_mroute_getsockopt(struct sock *sk,int optname,char __user *optval,int __user *optlen) 982 { 983 int olr; 984 int val; 985 986 if(optname!=MRT_VERSION && 987 #ifdef CONFIG_IP_PIMSM 988 optname!=MRT_PIM && 989 #endif 990 optname!=MRT_ASSERT) 991 return -ENOPROTOOPT; 992 993 if (get_user(olr, optlen)) 994 return -EFAULT; 995 996 olr = min_t(unsigned int, olr, sizeof(int)); 997 if (olr < 0) 998 return -EINVAL; 999 1000 if(put_user(olr,optlen)) 1001 return -EFAULT; 1002 if(optname==MRT_VERSION) 1003 val=0x0305; 1004 #ifdef CONFIG_IP_PIMSM 1005 else if(optname==MRT_PIM) 1006 val=mroute_do_pim; 1007 #endif 1008 else 1009 val=mroute_do_assert; 1010 if(copy_to_user(optval,&val,olr)) 1011 return -EFAULT; 1012 return 0; 1013 } 1014 1015 /* 1016 * The IP multicast ioctl support routines. 1017 */ 1018 1019 int ipmr_ioctl(struct sock *sk, int cmd, void __user *arg) 1020 { 1021 struct sioc_sg_req sr; 1022 struct sioc_vif_req vr; 1023 struct vif_device *vif; 1024 struct mfc_cache *c; 1025 1026 switch(cmd) 1027 { 1028 case SIOCGETVIFCNT: 1029 if (copy_from_user(&vr,arg,sizeof(vr))) 1030 return -EFAULT; 1031 if(vr.vifi>=maxvif) 1032 return -EINVAL; 1033 read_lock(&mrt_lock); 1034 vif=&vif_table[vr.vifi]; 1035 if(VIF_EXISTS(vr.vifi)) { 1036 vr.icount=vif->pkt_in; 1037 vr.ocount=vif->pkt_out; 1038 vr.ibytes=vif->bytes_in; 1039 vr.obytes=vif->bytes_out; 1040 read_unlock(&mrt_lock); 1041 1042 if (copy_to_user(arg,&vr,sizeof(vr))) 1043 return -EFAULT; 1044 return 0; 1045 } 1046 read_unlock(&mrt_lock); 1047 return -EADDRNOTAVAIL; 1048 case SIOCGETSGCNT: 1049 if (copy_from_user(&sr,arg,sizeof(sr))) 1050 return -EFAULT; 1051 1052 read_lock(&mrt_lock); 1053 c = ipmr_cache_find(sr.src.s_addr, sr.grp.s_addr); 1054 if (c) { 1055 sr.pktcnt = c->mfc_un.res.pkt; 1056 sr.bytecnt = c->mfc_un.res.bytes; 1057 sr.wrong_if = c->mfc_un.res.wrong_if; 1058 read_unlock(&mrt_lock); 1059 1060 if (copy_to_user(arg,&sr,sizeof(sr))) 1061 return -EFAULT; 1062 return 0; 1063 } 1064 read_unlock(&mrt_lock); 1065 return -EADDRNOTAVAIL; 1066 default: 1067 return -ENOIOCTLCMD; 1068 } 1069 } 1070 1071 1072 static int ipmr_device_event(struct notifier_block *this, unsigned long event, void *ptr) 1073 { 1074 struct vif_device *v; 1075 int ct; 1076 if (event != NETDEV_UNREGISTER) 1077 return NOTIFY_DONE; 1078 v=&vif_table[0]; 1079 for(ct=0;ct<maxvif;ct++,v++) { 1080 if (v->dev==ptr) 1081 vif_delete(ct); 1082 } 1083 return NOTIFY_DONE; 1084 } 1085 1086 1087 static struct notifier_block ip_mr_notifier={ 1088 .notifier_call = ipmr_device_event, 1089 }; 1090 1091 /* 1092 * Encapsulate a packet by attaching a valid IPIP header to it. 1093 * This avoids tunnel drivers and other mess and gives us the speed so 1094 * important for multicast video. 1095 */ 1096 1097 static void ip_encap(struct sk_buff *skb, u32 saddr, u32 daddr) 1098 { 1099 struct iphdr *iph = (struct iphdr *)skb_push(skb,sizeof(struct iphdr)); 1100 1101 iph->version = 4; 1102 iph->tos = skb->nh.iph->tos; 1103 iph->ttl = skb->nh.iph->ttl; 1104 iph->frag_off = 0; 1105 iph->daddr = daddr; 1106 iph->saddr = saddr; 1107 iph->protocol = IPPROTO_IPIP; 1108 iph->ihl = 5; 1109 iph->tot_len = htons(skb->len); 1110 ip_select_ident(iph, skb->dst, NULL); 1111 ip_send_check(iph); 1112 1113 skb->h.ipiph = skb->nh.iph; 1114 skb->nh.iph = iph; 1115 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); 1116 nf_reset(skb); 1117 } 1118 1119 static inline int ipmr_forward_finish(struct sk_buff *skb) 1120 { 1121 struct ip_options * opt = &(IPCB(skb)->opt); 1122 1123 IP_INC_STATS_BH(IPSTATS_MIB_OUTFORWDATAGRAMS); 1124 1125 if (unlikely(opt->optlen)) 1126 ip_forward_options(skb); 1127 1128 return dst_output(skb); 1129 } 1130 1131 /* 1132 * Processing handlers for ipmr_forward 1133 */ 1134 1135 static void ipmr_queue_xmit(struct sk_buff *skb, struct mfc_cache *c, int vifi) 1136 { 1137 struct iphdr *iph = skb->nh.iph; 1138 struct vif_device *vif = &vif_table[vifi]; 1139 struct net_device *dev; 1140 struct rtable *rt; 1141 int encap = 0; 1142 1143 if (vif->dev == NULL) 1144 goto out_free; 1145 1146 #ifdef CONFIG_IP_PIMSM 1147 if (vif->flags & VIFF_REGISTER) { 1148 vif->pkt_out++; 1149 vif->bytes_out+=skb->len; 1150 ((struct net_device_stats*)vif->dev->priv)->tx_bytes += skb->len; 1151 ((struct net_device_stats*)vif->dev->priv)->tx_packets++; 1152 ipmr_cache_report(skb, vifi, IGMPMSG_WHOLEPKT); 1153 kfree_skb(skb); 1154 return; 1155 } 1156 #endif 1157 1158 if (vif->flags&VIFF_TUNNEL) { 1159 struct flowi fl = { .oif = vif->link, 1160 .nl_u = { .ip4_u = 1161 { .daddr = vif->remote, 1162 .saddr = vif->local, 1163 .tos = RT_TOS(iph->tos) } }, 1164 .proto = IPPROTO_IPIP }; 1165 if (ip_route_output_key(&rt, &fl)) 1166 goto out_free; 1167 encap = sizeof(struct iphdr); 1168 } else { 1169 struct flowi fl = { .oif = vif->link, 1170 .nl_u = { .ip4_u = 1171 { .daddr = iph->daddr, 1172 .tos = RT_TOS(iph->tos) } }, 1173 .proto = IPPROTO_IPIP }; 1174 if (ip_route_output_key(&rt, &fl)) 1175 goto out_free; 1176 } 1177 1178 dev = rt->u.dst.dev; 1179 1180 if (skb->len+encap > dst_mtu(&rt->u.dst) && (ntohs(iph->frag_off) & IP_DF)) { 1181 /* Do not fragment multicasts. Alas, IPv4 does not 1182 allow to send ICMP, so that packets will disappear 1183 to blackhole. 1184 */ 1185 1186 IP_INC_STATS_BH(IPSTATS_MIB_FRAGFAILS); 1187 ip_rt_put(rt); 1188 goto out_free; 1189 } 1190 1191 encap += LL_RESERVED_SPACE(dev) + rt->u.dst.header_len; 1192 1193 if (skb_cow(skb, encap)) { 1194 ip_rt_put(rt); 1195 goto out_free; 1196 } 1197 1198 vif->pkt_out++; 1199 vif->bytes_out+=skb->len; 1200 1201 dst_release(skb->dst); 1202 skb->dst = &rt->u.dst; 1203 iph = skb->nh.iph; 1204 ip_decrease_ttl(iph); 1205 1206 /* FIXME: forward and output firewalls used to be called here. 1207 * What do we do with netfilter? -- RR */ 1208 if (vif->flags & VIFF_TUNNEL) { 1209 ip_encap(skb, vif->local, vif->remote); 1210 /* FIXME: extra output firewall step used to be here. --RR */ 1211 ((struct ip_tunnel *)vif->dev->priv)->stat.tx_packets++; 1212 ((struct ip_tunnel *)vif->dev->priv)->stat.tx_bytes+=skb->len; 1213 } 1214 1215 IPCB(skb)->flags |= IPSKB_FORWARDED; 1216 1217 /* 1218 * RFC1584 teaches, that DVMRP/PIM router must deliver packets locally 1219 * not only before forwarding, but after forwarding on all output 1220 * interfaces. It is clear, if mrouter runs a multicasting 1221 * program, it should receive packets not depending to what interface 1222 * program is joined. 1223 * If we will not make it, the program will have to join on all 1224 * interfaces. On the other hand, multihoming host (or router, but 1225 * not mrouter) cannot join to more than one interface - it will 1226 * result in receiving multiple packets. 1227 */ 1228 NF_HOOK(PF_INET, NF_IP_FORWARD, skb, skb->dev, dev, 1229 ipmr_forward_finish); 1230 return; 1231 1232 out_free: 1233 kfree_skb(skb); 1234 return; 1235 } 1236 1237 static int ipmr_find_vif(struct net_device *dev) 1238 { 1239 int ct; 1240 for (ct=maxvif-1; ct>=0; ct--) { 1241 if (vif_table[ct].dev == dev) 1242 break; 1243 } 1244 return ct; 1245 } 1246 1247 /* "local" means that we should preserve one skb (for local delivery) */ 1248 1249 static int ip_mr_forward(struct sk_buff *skb, struct mfc_cache *cache, int local) 1250 { 1251 int psend = -1; 1252 int vif, ct; 1253 1254 vif = cache->mfc_parent; 1255 cache->mfc_un.res.pkt++; 1256 cache->mfc_un.res.bytes += skb->len; 1257 1258 /* 1259 * Wrong interface: drop packet and (maybe) send PIM assert. 1260 */ 1261 if (vif_table[vif].dev != skb->dev) { 1262 int true_vifi; 1263 1264 if (((struct rtable*)skb->dst)->fl.iif == 0) { 1265 /* It is our own packet, looped back. 1266 Very complicated situation... 1267 1268 The best workaround until routing daemons will be 1269 fixed is not to redistribute packet, if it was 1270 send through wrong interface. It means, that 1271 multicast applications WILL NOT work for 1272 (S,G), which have default multicast route pointing 1273 to wrong oif. In any case, it is not a good 1274 idea to use multicasting applications on router. 1275 */ 1276 goto dont_forward; 1277 } 1278 1279 cache->mfc_un.res.wrong_if++; 1280 true_vifi = ipmr_find_vif(skb->dev); 1281 1282 if (true_vifi >= 0 && mroute_do_assert && 1283 /* pimsm uses asserts, when switching from RPT to SPT, 1284 so that we cannot check that packet arrived on an oif. 1285 It is bad, but otherwise we would need to move pretty 1286 large chunk of pimd to kernel. Ough... --ANK 1287 */ 1288 (mroute_do_pim || cache->mfc_un.res.ttls[true_vifi] < 255) && 1289 time_after(jiffies, 1290 cache->mfc_un.res.last_assert + MFC_ASSERT_THRESH)) { 1291 cache->mfc_un.res.last_assert = jiffies; 1292 ipmr_cache_report(skb, true_vifi, IGMPMSG_WRONGVIF); 1293 } 1294 goto dont_forward; 1295 } 1296 1297 vif_table[vif].pkt_in++; 1298 vif_table[vif].bytes_in+=skb->len; 1299 1300 /* 1301 * Forward the frame 1302 */ 1303 for (ct = cache->mfc_un.res.maxvif-1; ct >= cache->mfc_un.res.minvif; ct--) { 1304 if (skb->nh.iph->ttl > cache->mfc_un.res.ttls[ct]) { 1305 if (psend != -1) { 1306 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); 1307 if (skb2) 1308 ipmr_queue_xmit(skb2, cache, psend); 1309 } 1310 psend=ct; 1311 } 1312 } 1313 if (psend != -1) { 1314 if (local) { 1315 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); 1316 if (skb2) 1317 ipmr_queue_xmit(skb2, cache, psend); 1318 } else { 1319 ipmr_queue_xmit(skb, cache, psend); 1320 return 0; 1321 } 1322 } 1323 1324 dont_forward: 1325 if (!local) 1326 kfree_skb(skb); 1327 return 0; 1328 } 1329 1330 1331 /* 1332 * Multicast packets for forwarding arrive here 1333 */ 1334 1335 int ip_mr_input(struct sk_buff *skb) 1336 { 1337 struct mfc_cache *cache; 1338 int local = ((struct rtable*)skb->dst)->rt_flags&RTCF_LOCAL; 1339 1340 /* Packet is looped back after forward, it should not be 1341 forwarded second time, but still can be delivered locally. 1342 */ 1343 if (IPCB(skb)->flags&IPSKB_FORWARDED) 1344 goto dont_forward; 1345 1346 if (!local) { 1347 if (IPCB(skb)->opt.router_alert) { 1348 if (ip_call_ra_chain(skb)) 1349 return 0; 1350 } else if (skb->nh.iph->protocol == IPPROTO_IGMP){ 1351 /* IGMPv1 (and broken IGMPv2 implementations sort of 1352 Cisco IOS <= 11.2(8)) do not put router alert 1353 option to IGMP packets destined to routable 1354 groups. It is very bad, because it means 1355 that we can forward NO IGMP messages. 1356 */ 1357 read_lock(&mrt_lock); 1358 if (mroute_socket) { 1359 nf_reset(skb); 1360 raw_rcv(mroute_socket, skb); 1361 read_unlock(&mrt_lock); 1362 return 0; 1363 } 1364 read_unlock(&mrt_lock); 1365 } 1366 } 1367 1368 read_lock(&mrt_lock); 1369 cache = ipmr_cache_find(skb->nh.iph->saddr, skb->nh.iph->daddr); 1370 1371 /* 1372 * No usable cache entry 1373 */ 1374 if (cache==NULL) { 1375 int vif; 1376 1377 if (local) { 1378 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); 1379 ip_local_deliver(skb); 1380 if (skb2 == NULL) { 1381 read_unlock(&mrt_lock); 1382 return -ENOBUFS; 1383 } 1384 skb = skb2; 1385 } 1386 1387 vif = ipmr_find_vif(skb->dev); 1388 if (vif >= 0) { 1389 int err = ipmr_cache_unresolved(vif, skb); 1390 read_unlock(&mrt_lock); 1391 1392 return err; 1393 } 1394 read_unlock(&mrt_lock); 1395 kfree_skb(skb); 1396 return -ENODEV; 1397 } 1398 1399 ip_mr_forward(skb, cache, local); 1400 1401 read_unlock(&mrt_lock); 1402 1403 if (local) 1404 return ip_local_deliver(skb); 1405 1406 return 0; 1407 1408 dont_forward: 1409 if (local) 1410 return ip_local_deliver(skb); 1411 kfree_skb(skb); 1412 return 0; 1413 } 1414 1415 #ifdef CONFIG_IP_PIMSM_V1 1416 /* 1417 * Handle IGMP messages of PIMv1 1418 */ 1419 1420 int pim_rcv_v1(struct sk_buff * skb) 1421 { 1422 struct igmphdr *pim; 1423 struct iphdr *encap; 1424 struct net_device *reg_dev = NULL; 1425 1426 if (!pskb_may_pull(skb, sizeof(*pim) + sizeof(*encap))) 1427 goto drop; 1428 1429 pim = (struct igmphdr*)skb->h.raw; 1430 1431 if (!mroute_do_pim || 1432 skb->len < sizeof(*pim) + sizeof(*encap) || 1433 pim->group != PIM_V1_VERSION || pim->code != PIM_V1_REGISTER) 1434 goto drop; 1435 1436 encap = (struct iphdr*)(skb->h.raw + sizeof(struct igmphdr)); 1437 /* 1438 Check that: 1439 a. packet is really destinted to a multicast group 1440 b. packet is not a NULL-REGISTER 1441 c. packet is not truncated 1442 */ 1443 if (!MULTICAST(encap->daddr) || 1444 encap->tot_len == 0 || 1445 ntohs(encap->tot_len) + sizeof(*pim) > skb->len) 1446 goto drop; 1447 1448 read_lock(&mrt_lock); 1449 if (reg_vif_num >= 0) 1450 reg_dev = vif_table[reg_vif_num].dev; 1451 if (reg_dev) 1452 dev_hold(reg_dev); 1453 read_unlock(&mrt_lock); 1454 1455 if (reg_dev == NULL) 1456 goto drop; 1457 1458 skb->mac.raw = skb->nh.raw; 1459 skb_pull(skb, (u8*)encap - skb->data); 1460 skb->nh.iph = (struct iphdr *)skb->data; 1461 skb->dev = reg_dev; 1462 memset(&(IPCB(skb)->opt), 0, sizeof(struct ip_options)); 1463 skb->protocol = htons(ETH_P_IP); 1464 skb->ip_summed = 0; 1465 skb->pkt_type = PACKET_HOST; 1466 dst_release(skb->dst); 1467 skb->dst = NULL; 1468 ((struct net_device_stats*)reg_dev->priv)->rx_bytes += skb->len; 1469 ((struct net_device_stats*)reg_dev->priv)->rx_packets++; 1470 nf_reset(skb); 1471 netif_rx(skb); 1472 dev_put(reg_dev); 1473 return 0; 1474 drop: 1475 kfree_skb(skb); 1476 return 0; 1477 } 1478 #endif 1479 1480 #ifdef CONFIG_IP_PIMSM_V2 1481 static int pim_rcv(struct sk_buff * skb) 1482 { 1483 struct pimreghdr *pim; 1484 struct iphdr *encap; 1485 struct net_device *reg_dev = NULL; 1486 1487 if (!pskb_may_pull(skb, sizeof(*pim) + sizeof(*encap))) 1488 goto drop; 1489 1490 pim = (struct pimreghdr*)skb->h.raw; 1491 if (pim->type != ((PIM_VERSION<<4)|(PIM_REGISTER)) || 1492 (pim->flags&PIM_NULL_REGISTER) || 1493 (ip_compute_csum((void *)pim, sizeof(*pim)) != 0 && 1494 (u16)csum_fold(skb_checksum(skb, 0, skb->len, 0)))) 1495 goto drop; 1496 1497 /* check if the inner packet is destined to mcast group */ 1498 encap = (struct iphdr*)(skb->h.raw + sizeof(struct pimreghdr)); 1499 if (!MULTICAST(encap->daddr) || 1500 encap->tot_len == 0 || 1501 ntohs(encap->tot_len) + sizeof(*pim) > skb->len) 1502 goto drop; 1503 1504 read_lock(&mrt_lock); 1505 if (reg_vif_num >= 0) 1506 reg_dev = vif_table[reg_vif_num].dev; 1507 if (reg_dev) 1508 dev_hold(reg_dev); 1509 read_unlock(&mrt_lock); 1510 1511 if (reg_dev == NULL) 1512 goto drop; 1513 1514 skb->mac.raw = skb->nh.raw; 1515 skb_pull(skb, (u8*)encap - skb->data); 1516 skb->nh.iph = (struct iphdr *)skb->data; 1517 skb->dev = reg_dev; 1518 memset(&(IPCB(skb)->opt), 0, sizeof(struct ip_options)); 1519 skb->protocol = htons(ETH_P_IP); 1520 skb->ip_summed = 0; 1521 skb->pkt_type = PACKET_HOST; 1522 dst_release(skb->dst); 1523 ((struct net_device_stats*)reg_dev->priv)->rx_bytes += skb->len; 1524 ((struct net_device_stats*)reg_dev->priv)->rx_packets++; 1525 skb->dst = NULL; 1526 nf_reset(skb); 1527 netif_rx(skb); 1528 dev_put(reg_dev); 1529 return 0; 1530 drop: 1531 kfree_skb(skb); 1532 return 0; 1533 } 1534 #endif 1535 1536 static int 1537 ipmr_fill_mroute(struct sk_buff *skb, struct mfc_cache *c, struct rtmsg *rtm) 1538 { 1539 int ct; 1540 struct rtnexthop *nhp; 1541 struct net_device *dev = vif_table[c->mfc_parent].dev; 1542 u8 *b = skb->tail; 1543 struct rtattr *mp_head; 1544 1545 if (dev) 1546 RTA_PUT(skb, RTA_IIF, 4, &dev->ifindex); 1547 1548 mp_head = (struct rtattr*)skb_put(skb, RTA_LENGTH(0)); 1549 1550 for (ct = c->mfc_un.res.minvif; ct < c->mfc_un.res.maxvif; ct++) { 1551 if (c->mfc_un.res.ttls[ct] < 255) { 1552 if (skb_tailroom(skb) < RTA_ALIGN(RTA_ALIGN(sizeof(*nhp)) + 4)) 1553 goto rtattr_failure; 1554 nhp = (struct rtnexthop*)skb_put(skb, RTA_ALIGN(sizeof(*nhp))); 1555 nhp->rtnh_flags = 0; 1556 nhp->rtnh_hops = c->mfc_un.res.ttls[ct]; 1557 nhp->rtnh_ifindex = vif_table[ct].dev->ifindex; 1558 nhp->rtnh_len = sizeof(*nhp); 1559 } 1560 } 1561 mp_head->rta_type = RTA_MULTIPATH; 1562 mp_head->rta_len = skb->tail - (u8*)mp_head; 1563 rtm->rtm_type = RTN_MULTICAST; 1564 return 1; 1565 1566 rtattr_failure: 1567 skb_trim(skb, b - skb->data); 1568 return -EMSGSIZE; 1569 } 1570 1571 int ipmr_get_route(struct sk_buff *skb, struct rtmsg *rtm, int nowait) 1572 { 1573 int err; 1574 struct mfc_cache *cache; 1575 struct rtable *rt = (struct rtable*)skb->dst; 1576 1577 read_lock(&mrt_lock); 1578 cache = ipmr_cache_find(rt->rt_src, rt->rt_dst); 1579 1580 if (cache==NULL) { 1581 struct net_device *dev; 1582 int vif; 1583 1584 if (nowait) { 1585 read_unlock(&mrt_lock); 1586 return -EAGAIN; 1587 } 1588 1589 dev = skb->dev; 1590 if (dev == NULL || (vif = ipmr_find_vif(dev)) < 0) { 1591 read_unlock(&mrt_lock); 1592 return -ENODEV; 1593 } 1594 skb->nh.raw = skb_push(skb, sizeof(struct iphdr)); 1595 skb->nh.iph->ihl = sizeof(struct iphdr)>>2; 1596 skb->nh.iph->saddr = rt->rt_src; 1597 skb->nh.iph->daddr = rt->rt_dst; 1598 skb->nh.iph->version = 0; 1599 err = ipmr_cache_unresolved(vif, skb); 1600 read_unlock(&mrt_lock); 1601 return err; 1602 } 1603 1604 if (!nowait && (rtm->rtm_flags&RTM_F_NOTIFY)) 1605 cache->mfc_flags |= MFC_NOTIFY; 1606 err = ipmr_fill_mroute(skb, cache, rtm); 1607 read_unlock(&mrt_lock); 1608 return err; 1609 } 1610 1611 #ifdef CONFIG_PROC_FS 1612 /* 1613 * The /proc interfaces to multicast routing /proc/ip_mr_cache /proc/ip_mr_vif 1614 */ 1615 struct ipmr_vif_iter { 1616 int ct; 1617 }; 1618 1619 static struct vif_device *ipmr_vif_seq_idx(struct ipmr_vif_iter *iter, 1620 loff_t pos) 1621 { 1622 for (iter->ct = 0; iter->ct < maxvif; ++iter->ct) { 1623 if(!VIF_EXISTS(iter->ct)) 1624 continue; 1625 if (pos-- == 0) 1626 return &vif_table[iter->ct]; 1627 } 1628 return NULL; 1629 } 1630 1631 static void *ipmr_vif_seq_start(struct seq_file *seq, loff_t *pos) 1632 { 1633 read_lock(&mrt_lock); 1634 return *pos ? ipmr_vif_seq_idx(seq->private, *pos - 1) 1635 : SEQ_START_TOKEN; 1636 } 1637 1638 static void *ipmr_vif_seq_next(struct seq_file *seq, void *v, loff_t *pos) 1639 { 1640 struct ipmr_vif_iter *iter = seq->private; 1641 1642 ++*pos; 1643 if (v == SEQ_START_TOKEN) 1644 return ipmr_vif_seq_idx(iter, 0); 1645 1646 while (++iter->ct < maxvif) { 1647 if(!VIF_EXISTS(iter->ct)) 1648 continue; 1649 return &vif_table[iter->ct]; 1650 } 1651 return NULL; 1652 } 1653 1654 static void ipmr_vif_seq_stop(struct seq_file *seq, void *v) 1655 { 1656 read_unlock(&mrt_lock); 1657 } 1658 1659 static int ipmr_vif_seq_show(struct seq_file *seq, void *v) 1660 { 1661 if (v == SEQ_START_TOKEN) { 1662 seq_puts(seq, 1663 "Interface BytesIn PktsIn BytesOut PktsOut Flags Local Remote\n"); 1664 } else { 1665 const struct vif_device *vif = v; 1666 const char *name = vif->dev ? vif->dev->name : "none"; 1667 1668 seq_printf(seq, 1669 "%2Zd %-10s %8ld %7ld %8ld %7ld %05X %08X %08X\n", 1670 vif - vif_table, 1671 name, vif->bytes_in, vif->pkt_in, 1672 vif->bytes_out, vif->pkt_out, 1673 vif->flags, vif->local, vif->remote); 1674 } 1675 return 0; 1676 } 1677 1678 static struct seq_operations ipmr_vif_seq_ops = { 1679 .start = ipmr_vif_seq_start, 1680 .next = ipmr_vif_seq_next, 1681 .stop = ipmr_vif_seq_stop, 1682 .show = ipmr_vif_seq_show, 1683 }; 1684 1685 static int ipmr_vif_open(struct inode *inode, struct file *file) 1686 { 1687 struct seq_file *seq; 1688 int rc = -ENOMEM; 1689 struct ipmr_vif_iter *s = kmalloc(sizeof(*s), GFP_KERNEL); 1690 1691 if (!s) 1692 goto out; 1693 1694 rc = seq_open(file, &ipmr_vif_seq_ops); 1695 if (rc) 1696 goto out_kfree; 1697 1698 s->ct = 0; 1699 seq = file->private_data; 1700 seq->private = s; 1701 out: 1702 return rc; 1703 out_kfree: 1704 kfree(s); 1705 goto out; 1706 1707 } 1708 1709 static struct file_operations ipmr_vif_fops = { 1710 .owner = THIS_MODULE, 1711 .open = ipmr_vif_open, 1712 .read = seq_read, 1713 .llseek = seq_lseek, 1714 .release = seq_release_private, 1715 }; 1716 1717 struct ipmr_mfc_iter { 1718 struct mfc_cache **cache; 1719 int ct; 1720 }; 1721 1722 1723 static struct mfc_cache *ipmr_mfc_seq_idx(struct ipmr_mfc_iter *it, loff_t pos) 1724 { 1725 struct mfc_cache *mfc; 1726 1727 it->cache = mfc_cache_array; 1728 read_lock(&mrt_lock); 1729 for (it->ct = 0; it->ct < MFC_LINES; it->ct++) 1730 for(mfc = mfc_cache_array[it->ct]; mfc; mfc = mfc->next) 1731 if (pos-- == 0) 1732 return mfc; 1733 read_unlock(&mrt_lock); 1734 1735 it->cache = &mfc_unres_queue; 1736 spin_lock_bh(&mfc_unres_lock); 1737 for(mfc = mfc_unres_queue; mfc; mfc = mfc->next) 1738 if (pos-- == 0) 1739 return mfc; 1740 spin_unlock_bh(&mfc_unres_lock); 1741 1742 it->cache = NULL; 1743 return NULL; 1744 } 1745 1746 1747 static void *ipmr_mfc_seq_start(struct seq_file *seq, loff_t *pos) 1748 { 1749 struct ipmr_mfc_iter *it = seq->private; 1750 it->cache = NULL; 1751 it->ct = 0; 1752 return *pos ? ipmr_mfc_seq_idx(seq->private, *pos - 1) 1753 : SEQ_START_TOKEN; 1754 } 1755 1756 static void *ipmr_mfc_seq_next(struct seq_file *seq, void *v, loff_t *pos) 1757 { 1758 struct mfc_cache *mfc = v; 1759 struct ipmr_mfc_iter *it = seq->private; 1760 1761 ++*pos; 1762 1763 if (v == SEQ_START_TOKEN) 1764 return ipmr_mfc_seq_idx(seq->private, 0); 1765 1766 if (mfc->next) 1767 return mfc->next; 1768 1769 if (it->cache == &mfc_unres_queue) 1770 goto end_of_list; 1771 1772 BUG_ON(it->cache != mfc_cache_array); 1773 1774 while (++it->ct < MFC_LINES) { 1775 mfc = mfc_cache_array[it->ct]; 1776 if (mfc) 1777 return mfc; 1778 } 1779 1780 /* exhausted cache_array, show unresolved */ 1781 read_unlock(&mrt_lock); 1782 it->cache = &mfc_unres_queue; 1783 it->ct = 0; 1784 1785 spin_lock_bh(&mfc_unres_lock); 1786 mfc = mfc_unres_queue; 1787 if (mfc) 1788 return mfc; 1789 1790 end_of_list: 1791 spin_unlock_bh(&mfc_unres_lock); 1792 it->cache = NULL; 1793 1794 return NULL; 1795 } 1796 1797 static void ipmr_mfc_seq_stop(struct seq_file *seq, void *v) 1798 { 1799 struct ipmr_mfc_iter *it = seq->private; 1800 1801 if (it->cache == &mfc_unres_queue) 1802 spin_unlock_bh(&mfc_unres_lock); 1803 else if (it->cache == mfc_cache_array) 1804 read_unlock(&mrt_lock); 1805 } 1806 1807 static int ipmr_mfc_seq_show(struct seq_file *seq, void *v) 1808 { 1809 int n; 1810 1811 if (v == SEQ_START_TOKEN) { 1812 seq_puts(seq, 1813 "Group Origin Iif Pkts Bytes Wrong Oifs\n"); 1814 } else { 1815 const struct mfc_cache *mfc = v; 1816 const struct ipmr_mfc_iter *it = seq->private; 1817 1818 seq_printf(seq, "%08lX %08lX %-3d %8ld %8ld %8ld", 1819 (unsigned long) mfc->mfc_mcastgrp, 1820 (unsigned long) mfc->mfc_origin, 1821 mfc->mfc_parent, 1822 mfc->mfc_un.res.pkt, 1823 mfc->mfc_un.res.bytes, 1824 mfc->mfc_un.res.wrong_if); 1825 1826 if (it->cache != &mfc_unres_queue) { 1827 for(n = mfc->mfc_un.res.minvif; 1828 n < mfc->mfc_un.res.maxvif; n++ ) { 1829 if(VIF_EXISTS(n) 1830 && mfc->mfc_un.res.ttls[n] < 255) 1831 seq_printf(seq, 1832 " %2d:%-3d", 1833 n, mfc->mfc_un.res.ttls[n]); 1834 } 1835 } 1836 seq_putc(seq, '\n'); 1837 } 1838 return 0; 1839 } 1840 1841 static struct seq_operations ipmr_mfc_seq_ops = { 1842 .start = ipmr_mfc_seq_start, 1843 .next = ipmr_mfc_seq_next, 1844 .stop = ipmr_mfc_seq_stop, 1845 .show = ipmr_mfc_seq_show, 1846 }; 1847 1848 static int ipmr_mfc_open(struct inode *inode, struct file *file) 1849 { 1850 struct seq_file *seq; 1851 int rc = -ENOMEM; 1852 struct ipmr_mfc_iter *s = kmalloc(sizeof(*s), GFP_KERNEL); 1853 1854 if (!s) 1855 goto out; 1856 1857 rc = seq_open(file, &ipmr_mfc_seq_ops); 1858 if (rc) 1859 goto out_kfree; 1860 1861 seq = file->private_data; 1862 seq->private = s; 1863 out: 1864 return rc; 1865 out_kfree: 1866 kfree(s); 1867 goto out; 1868 1869 } 1870 1871 static struct file_operations ipmr_mfc_fops = { 1872 .owner = THIS_MODULE, 1873 .open = ipmr_mfc_open, 1874 .read = seq_read, 1875 .llseek = seq_lseek, 1876 .release = seq_release_private, 1877 }; 1878 #endif 1879 1880 #ifdef CONFIG_IP_PIMSM_V2 1881 static struct net_protocol pim_protocol = { 1882 .handler = pim_rcv, 1883 }; 1884 #endif 1885 1886 1887 /* 1888 * Setup for IP multicast routing 1889 */ 1890 1891 void __init ip_mr_init(void) 1892 { 1893 mrt_cachep = kmem_cache_create("ip_mrt_cache", 1894 sizeof(struct mfc_cache), 1895 0, SLAB_HWCACHE_ALIGN, 1896 NULL, NULL); 1897 if (!mrt_cachep) 1898 panic("cannot allocate ip_mrt_cache"); 1899 1900 init_timer(&ipmr_expire_timer); 1901 ipmr_expire_timer.function=ipmr_expire_process; 1902 register_netdevice_notifier(&ip_mr_notifier); 1903 #ifdef CONFIG_PROC_FS 1904 proc_net_fops_create("ip_mr_vif", 0, &ipmr_vif_fops); 1905 proc_net_fops_create("ip_mr_cache", 0, &ipmr_mfc_fops); 1906 #endif 1907 } 1908