Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)
[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]
FreeBSD/Linux Kernel Cross Reference
sys/netgraph/ng_bridge.c
Version:
- FREEBSD - FREEBSD-13-STABLE - FREEBSD-13-0 - FREEBSD-12-STABLE - FREEBSD-12-0 - FREEBSD-11-STABLE - FREEBSD-11-0 - FREEBSD-10-STABLE - FREEBSD-10-0 - FREEBSD-9-STABLE - FREEBSD-9-0 - FREEBSD-8-STABLE - FREEBSD-8-0 - FREEBSD-7-STABLE - FREEBSD-7-0 - FREEBSD-6-STABLE - FREEBSD-6-0 - FREEBSD-5-STABLE - FREEBSD-5-0 - FREEBSD-4-STABLE - FREEBSD-3-STABLE - FREEBSD22 - l41 - OPENBSD - linux-2.6 - MK84 - PLAN9 - xnu-8792
SearchContext: - none - 3 - 10
SearchContext: - none - 3 - 10
1 /* 2 * ng_bridge.c 3 */ 4 5 /*- 6 * Copyright (c) 2000 Whistle Communications, Inc. 7 * All rights reserved. 8 * 9 * Subject to the following obligations and disclaimer of warranty, use and 10 * redistribution of this software, in source or object code forms, with or 11 * without modifications are expressly permitted by Whistle Communications; 12 * provided, however, that: 13 * 1. Any and all reproductions of the source or object code must include the 14 * copyright notice above and the following disclaimer of warranties; and 15 * 2. No rights are granted, in any manner or form, to use Whistle 16 * Communications, Inc. trademarks, including the mark "WHISTLE 17 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as 18 * such appears in the above copyright notice or in the software. 19 * 20 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND 21 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO 22 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE, 23 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF 24 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. 25 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY 26 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS 27 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE. 28 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES 29 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING 30 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 31 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR 32 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY 33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 35 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY 36 * OF SUCH DAMAGE. 37 * 38 * Author: Archie Cobbs <archie@freebsd.org> 39 * 40 * $FreeBSD: releng/9.0/sys/netgraph/ng_bridge.c 220768 2011-04-18 09:12:27Z glebius $ 41 */ 42 43 /* 44 * ng_bridge(4) netgraph node type 45 * 46 * The node performs standard intelligent Ethernet bridging over 47 * each of its connected hooks, or links. A simple loop detection 48 * algorithm is included which disables a link for priv->conf.loopTimeout 49 * seconds when a host is seen to have jumped from one link to 50 * another within priv->conf.minStableAge seconds. 51 * 52 * We keep a hashtable that maps Ethernet addresses to host info, 53 * which is contained in struct ng_bridge_host's. These structures 54 * tell us on which link the host may be found. A host's entry will 55 * expire after priv->conf.maxStaleness seconds. 56 * 57 * This node is optimzed for stable networks, where machines jump 58 * from one port to the other only rarely. 59 */ 60 61 #include <sys/param.h> 62 #include <sys/systm.h> 63 #include <sys/kernel.h> 64 #include <sys/lock.h> 65 #include <sys/malloc.h> 66 #include <sys/mbuf.h> 67 #include <sys/errno.h> 68 #include <sys/rwlock.h> 69 #include <sys/syslog.h> 70 #include <sys/socket.h> 71 #include <sys/ctype.h> 72 73 #include <net/if.h> 74 #include <net/ethernet.h> 75 #include <net/vnet.h> 76 77 #include <netinet/in.h> 78 #if 0 /* not used yet */ 79 #include <netinet/ip_fw.h> 80 #endif 81 #include <netgraph/ng_message.h> 82 #include <netgraph/netgraph.h> 83 #include <netgraph/ng_parse.h> 84 #include <netgraph/ng_bridge.h> 85 86 #ifdef NG_SEPARATE_MALLOC 87 MALLOC_DEFINE(M_NETGRAPH_BRIDGE, "netgraph_bridge", "netgraph bridge node"); 88 #else 89 #define M_NETGRAPH_BRIDGE M_NETGRAPH 90 #endif 91 92 /* Per-link private data */ 93 struct ng_bridge_link { 94 hook_p hook; /* netgraph hook */ 95 u_int16_t loopCount; /* loop ignore timer */ 96 struct ng_bridge_link_stats stats; /* link stats */ 97 }; 98 99 /* Per-node private data */ 100 struct ng_bridge_private { 101 struct ng_bridge_bucket *tab; /* hash table bucket array */ 102 struct ng_bridge_link *links[NG_BRIDGE_MAX_LINKS]; 103 struct ng_bridge_config conf; /* node configuration */ 104 node_p node; /* netgraph node */ 105 u_int numHosts; /* num entries in table */ 106 u_int numBuckets; /* num buckets in table */ 107 u_int hashMask; /* numBuckets - 1 */ 108 int numLinks; /* num connected links */ 109 int persistent; /* can exist w/o hooks */ 110 struct callout timer; /* one second periodic timer */ 111 }; 112 typedef struct ng_bridge_private *priv_p; 113 114 /* Information about a host, stored in a hash table entry */ 115 struct ng_bridge_hent { 116 struct ng_bridge_host host; /* actual host info */ 117 SLIST_ENTRY(ng_bridge_hent) next; /* next entry in bucket */ 118 }; 119 120 /* Hash table bucket declaration */ 121 SLIST_HEAD(ng_bridge_bucket, ng_bridge_hent); 122 123 /* Netgraph node methods */ 124 static ng_constructor_t ng_bridge_constructor; 125 static ng_rcvmsg_t ng_bridge_rcvmsg; 126 static ng_shutdown_t ng_bridge_shutdown; 127 static ng_newhook_t ng_bridge_newhook; 128 static ng_rcvdata_t ng_bridge_rcvdata; 129 static ng_disconnect_t ng_bridge_disconnect; 130 131 /* Other internal functions */ 132 static struct ng_bridge_host *ng_bridge_get(priv_p priv, const u_char *addr); 133 static int ng_bridge_put(priv_p priv, const u_char *addr, int linkNum); 134 static void ng_bridge_rehash(priv_p priv); 135 static void ng_bridge_remove_hosts(priv_p priv, int linkNum); 136 static void ng_bridge_timeout(node_p node, hook_p hook, void *arg1, int arg2); 137 static const char *ng_bridge_nodename(node_p node); 138 139 /* Ethernet broadcast */ 140 static const u_char ng_bridge_bcast_addr[ETHER_ADDR_LEN] = 141 { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; 142 143 /* Store each hook's link number in the private field */ 144 #define LINK_NUM(hook) (*(u_int16_t *)(&(hook)->private)) 145 146 /* Compare Ethernet addresses using 32 and 16 bit words instead of bytewise */ 147 #define ETHER_EQUAL(a,b) (((const u_int32_t *)(a))[0] \ 148 == ((const u_int32_t *)(b))[0] \ 149 && ((const u_int16_t *)(a))[2] \ 150 == ((const u_int16_t *)(b))[2]) 151 152 /* Minimum and maximum number of hash buckets. Must be a power of two. */ 153 #define MIN_BUCKETS (1 << 5) /* 32 */ 154 #define MAX_BUCKETS (1 << 14) /* 16384 */ 155 156 /* Configuration default values */ 157 #define DEFAULT_LOOP_TIMEOUT 60 158 #define DEFAULT_MAX_STALENESS (15 * 60) /* same as ARP timeout */ 159 #define DEFAULT_MIN_STABLE_AGE 1 160 161 /****************************************************************** 162 NETGRAPH PARSE TYPES 163 ******************************************************************/ 164 165 /* 166 * How to determine the length of the table returned by NGM_BRIDGE_GET_TABLE 167 */ 168 static int 169 ng_bridge_getTableLength(const struct ng_parse_type *type, 170 const u_char *start, const u_char *buf) 171 { 172 const struct ng_bridge_host_ary *const hary 173 = (const struct ng_bridge_host_ary *)(buf - sizeof(u_int32_t)); 174 175 return hary->numHosts; 176 } 177 178 /* Parse type for struct ng_bridge_host_ary */ 179 static const struct ng_parse_struct_field ng_bridge_host_type_fields[] 180 = NG_BRIDGE_HOST_TYPE_INFO(&ng_parse_enaddr_type); 181 static const struct ng_parse_type ng_bridge_host_type = { 182 &ng_parse_struct_type, 183 &ng_bridge_host_type_fields 184 }; 185 static const struct ng_parse_array_info ng_bridge_hary_type_info = { 186 &ng_bridge_host_type, 187 ng_bridge_getTableLength 188 }; 189 static const struct ng_parse_type ng_bridge_hary_type = { 190 &ng_parse_array_type, 191 &ng_bridge_hary_type_info 192 }; 193 static const struct ng_parse_struct_field ng_bridge_host_ary_type_fields[] 194 = NG_BRIDGE_HOST_ARY_TYPE_INFO(&ng_bridge_hary_type); 195 static const struct ng_parse_type ng_bridge_host_ary_type = { 196 &ng_parse_struct_type, 197 &ng_bridge_host_ary_type_fields 198 }; 199 200 /* Parse type for struct ng_bridge_config */ 201 static const struct ng_parse_fixedarray_info ng_bridge_ipfwary_type_info = { 202 &ng_parse_uint8_type, 203 NG_BRIDGE_MAX_LINKS 204 }; 205 static const struct ng_parse_type ng_bridge_ipfwary_type = { 206 &ng_parse_fixedarray_type, 207 &ng_bridge_ipfwary_type_info 208 }; 209 static const struct ng_parse_struct_field ng_bridge_config_type_fields[] 210 = NG_BRIDGE_CONFIG_TYPE_INFO(&ng_bridge_ipfwary_type); 211 static const struct ng_parse_type ng_bridge_config_type = { 212 &ng_parse_struct_type, 213 &ng_bridge_config_type_fields 214 }; 215 216 /* Parse type for struct ng_bridge_link_stat */ 217 static const struct ng_parse_struct_field ng_bridge_stats_type_fields[] 218 = NG_BRIDGE_STATS_TYPE_INFO; 219 static const struct ng_parse_type ng_bridge_stats_type = { 220 &ng_parse_struct_type, 221 &ng_bridge_stats_type_fields 222 }; 223 224 /* List of commands and how to convert arguments to/from ASCII */ 225 static const struct ng_cmdlist ng_bridge_cmdlist[] = { 226 { 227 NGM_BRIDGE_COOKIE, 228 NGM_BRIDGE_SET_CONFIG, 229 "setconfig", 230 &ng_bridge_config_type, 231 NULL 232 }, 233 { 234 NGM_BRIDGE_COOKIE, 235 NGM_BRIDGE_GET_CONFIG, 236 "getconfig", 237 NULL, 238 &ng_bridge_config_type 239 }, 240 { 241 NGM_BRIDGE_COOKIE, 242 NGM_BRIDGE_RESET, 243 "reset", 244 NULL, 245 NULL 246 }, 247 { 248 NGM_BRIDGE_COOKIE, 249 NGM_BRIDGE_GET_STATS, 250 "getstats", 251 &ng_parse_uint32_type, 252 &ng_bridge_stats_type 253 }, 254 { 255 NGM_BRIDGE_COOKIE, 256 NGM_BRIDGE_CLR_STATS, 257 "clrstats", 258 &ng_parse_uint32_type, 259 NULL 260 }, 261 { 262 NGM_BRIDGE_COOKIE, 263 NGM_BRIDGE_GETCLR_STATS, 264 "getclrstats", 265 &ng_parse_uint32_type, 266 &ng_bridge_stats_type 267 }, 268 { 269 NGM_BRIDGE_COOKIE, 270 NGM_BRIDGE_GET_TABLE, 271 "gettable", 272 NULL, 273 &ng_bridge_host_ary_type 274 }, 275 { 276 NGM_BRIDGE_COOKIE, 277 NGM_BRIDGE_SET_PERSISTENT, 278 "setpersistent", 279 NULL, 280 NULL 281 }, 282 { 0 } 283 }; 284 285 /* Node type descriptor */ 286 static struct ng_type ng_bridge_typestruct = { 287 .version = NG_ABI_VERSION, 288 .name = NG_BRIDGE_NODE_TYPE, 289 .constructor = ng_bridge_constructor, 290 .rcvmsg = ng_bridge_rcvmsg, 291 .shutdown = ng_bridge_shutdown, 292 .newhook = ng_bridge_newhook, 293 .rcvdata = ng_bridge_rcvdata, 294 .disconnect = ng_bridge_disconnect, 295 .cmdlist = ng_bridge_cmdlist, 296 }; 297 NETGRAPH_INIT(bridge, &ng_bridge_typestruct); 298 299 /****************************************************************** 300 NETGRAPH NODE METHODS 301 ******************************************************************/ 302 303 /* 304 * Node constructor 305 */ 306 static int 307 ng_bridge_constructor(node_p node) 308 { 309 priv_p priv; 310 311 /* Allocate and initialize private info */ 312 priv = malloc(sizeof(*priv), M_NETGRAPH_BRIDGE, M_WAITOK | M_ZERO); 313 ng_callout_init(&priv->timer); 314 315 /* Allocate and initialize hash table, etc. */ 316 priv->tab = malloc(MIN_BUCKETS * sizeof(*priv->tab), 317 M_NETGRAPH_BRIDGE, M_WAITOK | M_ZERO); 318 priv->numBuckets = MIN_BUCKETS; 319 priv->hashMask = MIN_BUCKETS - 1; 320 priv->conf.debugLevel = 1; 321 priv->conf.loopTimeout = DEFAULT_LOOP_TIMEOUT; 322 priv->conf.maxStaleness = DEFAULT_MAX_STALENESS; 323 priv->conf.minStableAge = DEFAULT_MIN_STABLE_AGE; 324 325 /* 326 * This node has all kinds of stuff that could be screwed by SMP. 327 * Until it gets it's own internal protection, we go through in 328 * single file. This could hurt a machine bridging beteen two 329 * GB ethernets so it should be fixed. 330 * When it's fixed the process SHOULD NOT SLEEP, spinlocks please! 331 * (and atomic ops ) 332 */ 333 NG_NODE_FORCE_WRITER(node); 334 NG_NODE_SET_PRIVATE(node, priv); 335 priv->node = node; 336 337 /* Start timer; timer is always running while node is alive */ 338 ng_callout(&priv->timer, node, NULL, hz, ng_bridge_timeout, NULL, 0); 339 340 /* Done */ 341 return (0); 342 } 343 344 /* 345 * Method for attaching a new hook 346 */ 347 static int 348 ng_bridge_newhook(node_p node, hook_p hook, const char *name) 349 { 350 const priv_p priv = NG_NODE_PRIVATE(node); 351 352 /* Check for a link hook */ 353 if (strncmp(name, NG_BRIDGE_HOOK_LINK_PREFIX, 354 strlen(NG_BRIDGE_HOOK_LINK_PREFIX)) == 0) { 355 const char *cp; 356 char *eptr; 357 u_long linkNum; 358 359 cp = name + strlen(NG_BRIDGE_HOOK_LINK_PREFIX); 360 if (!isdigit(*cp) || (cp[0] == '' && cp[1] != '\0')) 361 return (EINVAL); 362 linkNum = strtoul(cp, &eptr, 10); 363 if (*eptr != '\0' || linkNum >= NG_BRIDGE_MAX_LINKS) 364 return (EINVAL); 365 if (priv->links[linkNum] != NULL) 366 return (EISCONN); 367 priv->links[linkNum] = malloc(sizeof(*priv->links[linkNum]), 368 M_NETGRAPH_BRIDGE, M_NOWAIT|M_ZERO); 369 if (priv->links[linkNum] == NULL) 370 return (ENOMEM); 371 priv->links[linkNum]->hook = hook; 372 NG_HOOK_SET_PRIVATE(hook, (void *)linkNum); 373 priv->numLinks++; 374 return (0); 375 } 376 377 /* Unknown hook name */ 378 return (EINVAL); 379 } 380 381 /* 382 * Receive a control message 383 */ 384 static int 385 ng_bridge_rcvmsg(node_p node, item_p item, hook_p lasthook) 386 { 387 const priv_p priv = NG_NODE_PRIVATE(node); 388 struct ng_mesg *resp = NULL; 389 int error = 0; 390 struct ng_mesg *msg; 391 392 NGI_GET_MSG(item, msg); 393 switch (msg->header.typecookie) { 394 case NGM_BRIDGE_COOKIE: 395 switch (msg->header.cmd) { 396 case NGM_BRIDGE_GET_CONFIG: 397 { 398 struct ng_bridge_config *conf; 399 400 NG_MKRESPONSE(resp, msg, 401 sizeof(struct ng_bridge_config), M_NOWAIT); 402 if (resp == NULL) { 403 error = ENOMEM; 404 break; 405 } 406 conf = (struct ng_bridge_config *)resp->data; 407 *conf = priv->conf; /* no sanity checking needed */ 408 break; 409 } 410 case NGM_BRIDGE_SET_CONFIG: 411 { 412 struct ng_bridge_config *conf; 413 int i; 414 415 if (msg->header.arglen 416 != sizeof(struct ng_bridge_config)) { 417 error = EINVAL; 418 break; 419 } 420 conf = (struct ng_bridge_config *)msg->data; 421 priv->conf = *conf; 422 for (i = 0; i < NG_BRIDGE_MAX_LINKS; i++) 423 priv->conf.ipfw[i] = !!priv->conf.ipfw[i]; 424 break; 425 } 426 case NGM_BRIDGE_RESET: 427 { 428 int i; 429 430 /* Flush all entries in the hash table */ 431 ng_bridge_remove_hosts(priv, -1); 432 433 /* Reset all loop detection counters and stats */ 434 for (i = 0; i < NG_BRIDGE_MAX_LINKS; i++) { 435 if (priv->links[i] == NULL) 436 continue; 437 priv->links[i]->loopCount = 0; 438 bzero(&priv->links[i]->stats, 439 sizeof(priv->links[i]->stats)); 440 } 441 break; 442 } 443 case NGM_BRIDGE_GET_STATS: 444 case NGM_BRIDGE_CLR_STATS: 445 case NGM_BRIDGE_GETCLR_STATS: 446 { 447 struct ng_bridge_link *link; 448 int linkNum; 449 450 /* Get link number */ 451 if (msg->header.arglen != sizeof(u_int32_t)) { 452 error = EINVAL; 453 break; 454 } 455 linkNum = *((u_int32_t *)msg->data); 456 if (linkNum < 0 || linkNum >= NG_BRIDGE_MAX_LINKS) { 457 error = EINVAL; 458 break; 459 } 460 if ((link = priv->links[linkNum]) == NULL) { 461 error = ENOTCONN; 462 break; 463 } 464 465 /* Get/clear stats */ 466 if (msg->header.cmd != NGM_BRIDGE_CLR_STATS) { 467 NG_MKRESPONSE(resp, msg, 468 sizeof(link->stats), M_NOWAIT); 469 if (resp == NULL) { 470 error = ENOMEM; 471 break; 472 } 473 bcopy(&link->stats, 474 resp->data, sizeof(link->stats)); 475 } 476 if (msg->header.cmd != NGM_BRIDGE_GET_STATS) 477 bzero(&link->stats, sizeof(link->stats)); 478 break; 479 } 480 case NGM_BRIDGE_GET_TABLE: 481 { 482 struct ng_bridge_host_ary *ary; 483 struct ng_bridge_hent *hent; 484 int i = 0, bucket; 485 486 NG_MKRESPONSE(resp, msg, sizeof(*ary) 487 + (priv->numHosts * sizeof(*ary->hosts)), M_NOWAIT); 488 if (resp == NULL) { 489 error = ENOMEM; 490 break; 491 } 492 ary = (struct ng_bridge_host_ary *)resp->data; 493 ary->numHosts = priv->numHosts; 494 for (bucket = 0; bucket < priv->numBuckets; bucket++) { 495 SLIST_FOREACH(hent, &priv->tab[bucket], next) 496 ary->hosts[i++] = hent->host; 497 } 498 break; 499 } 500 case NGM_BRIDGE_SET_PERSISTENT: 501 { 502 priv->persistent = 1; 503 break; 504 } 505 default: 506 error = EINVAL; 507 break; 508 } 509 break; 510 default: 511 error = EINVAL; 512 break; 513 } 514 515 /* Done */ 516 NG_RESPOND_MSG(error, node, item, resp); 517 NG_FREE_MSG(msg); 518 return (error); 519 } 520 521 /* 522 * Receive data on a hook 523 */ 524 static int 525 ng_bridge_rcvdata(hook_p hook, item_p item) 526 { 527 const node_p node = NG_HOOK_NODE(hook); 528 const priv_p priv = NG_NODE_PRIVATE(node); 529 struct ng_bridge_host *host; 530 struct ng_bridge_link *link; 531 struct ether_header *eh; 532 int error = 0, linkNum, linksSeen; 533 int manycast; 534 struct mbuf *m; 535 struct ng_bridge_link *firstLink; 536 537 NGI_GET_M(item, m); 538 /* Get link number */ 539 linkNum = (intptr_t)NG_HOOK_PRIVATE(hook); 540 KASSERT(linkNum >= 0 && linkNum < NG_BRIDGE_MAX_LINKS, 541 ("%s: linkNum=%u", __func__, linkNum)); 542 link = priv->links[linkNum]; 543 KASSERT(link != NULL, ("%s: link%d null", __func__, linkNum)); 544 545 /* Sanity check packet and pull up header */ 546 if (m->m_pkthdr.len < ETHER_HDR_LEN) { 547 link->stats.recvRunts++; 548 NG_FREE_ITEM(item); 549 NG_FREE_M(m); 550 return (EINVAL); 551 } 552 if (m->m_len < ETHER_HDR_LEN && !(m = m_pullup(m, ETHER_HDR_LEN))) { 553 link->stats.memoryFailures++; 554 NG_FREE_ITEM(item); 555 return (ENOBUFS); 556 } 557 eh = mtod(m, struct ether_header *); 558 if ((eh->ether_shost[0] & 1) != 0) { 559 link->stats.recvInvalid++; 560 NG_FREE_ITEM(item); 561 NG_FREE_M(m); 562 return (EINVAL); 563 } 564 565 /* Is link disabled due to a loopback condition? */ 566 if (link->loopCount != 0) { 567 link->stats.loopDrops++; 568 NG_FREE_ITEM(item); 569 NG_FREE_M(m); 570 return (ELOOP); /* XXX is this an appropriate error? */ 571 } 572 573 /* Update stats */ 574 link->stats.recvPackets++; 575 link->stats.recvOctets += m->m_pkthdr.len; 576 if ((manycast = (eh->ether_dhost[0] & 1)) != 0) { 577 if (ETHER_EQUAL(eh->ether_dhost, ng_bridge_bcast_addr)) { 578 link->stats.recvBroadcasts++; 579 manycast = 2; 580 } else 581 link->stats.recvMulticasts++; 582 } 583 584 /* Look up packet's source Ethernet address in hashtable */ 585 if ((host = ng_bridge_get(priv, eh->ether_shost)) != NULL) { 586 587 /* Update time since last heard from this host */ 588 host->staleness = 0; 589 590 /* Did host jump to a different link? */ 591 if (host->linkNum != linkNum) { 592 593 /* 594 * If the host's old link was recently established 595 * on the old link and it's already jumped to a new 596 * link, declare a loopback condition. 597 */ 598 if (host->age < priv->conf.minStableAge) { 599 600 /* Log the problem */ 601 if (priv->conf.debugLevel >= 2) { 602 struct ifnet *ifp = m->m_pkthdr.rcvif; 603 char suffix[32]; 604 605 if (ifp != NULL) 606 snprintf(suffix, sizeof(suffix), 607 " (%s)", ifp->if_xname); 608 else 609 *suffix = '\0'; 610 log(LOG_WARNING, "ng_bridge: %s:" 611 " loopback detected on %s%s\n", 612 ng_bridge_nodename(node), 613 NG_HOOK_NAME(hook), suffix); 614 } 615 616 /* Mark link as linka non grata */ 617 link->loopCount = priv->conf.loopTimeout; 618 link->stats.loopDetects++; 619 620 /* Forget all hosts on this link */ 621 ng_bridge_remove_hosts(priv, linkNum); 622 623 /* Drop packet */ 624 link->stats.loopDrops++; 625 NG_FREE_ITEM(item); 626 NG_FREE_M(m); 627 return (ELOOP); /* XXX appropriate? */ 628 } 629 630 /* Move host over to new link */ 631 host->linkNum = linkNum; 632 host->age = 0; 633 } 634 } else { 635 if (!ng_bridge_put(priv, eh->ether_shost, linkNum)) { 636 link->stats.memoryFailures++; 637 NG_FREE_ITEM(item); 638 NG_FREE_M(m); 639 return (ENOMEM); 640 } 641 } 642 643 /* Run packet through ipfw processing, if enabled */ 644 #if 0 645 if (priv->conf.ipfw[linkNum] && V_fw_enable && V_ip_fw_chk_ptr != NULL) { 646 /* XXX not implemented yet */ 647 } 648 #endif 649 650 /* 651 * If unicast and destination host known, deliver to host's link, 652 * unless it is the same link as the packet came in on. 653 */ 654 if (!manycast) { 655 656 /* Determine packet destination link */ 657 if ((host = ng_bridge_get(priv, eh->ether_dhost)) != NULL) { 658 struct ng_bridge_link *const destLink 659 = priv->links[host->linkNum]; 660 661 /* If destination same as incoming link, do nothing */ 662 KASSERT(destLink != NULL, 663 ("%s: link%d null", __func__, host->linkNum)); 664 if (destLink == link) { 665 NG_FREE_ITEM(item); 666 NG_FREE_M(m); 667 return (0); 668 } 669 670 /* Deliver packet out the destination link */ 671 destLink->stats.xmitPackets++; 672 destLink->stats.xmitOctets += m->m_pkthdr.len; 673 NG_FWD_NEW_DATA(error, item, destLink->hook, m); 674 return (error); 675 } 676 677 /* Destination host is not known */ 678 link->stats.recvUnknown++; 679 } 680 681 /* Distribute unknown, multicast, broadcast pkts to all other links */ 682 firstLink = NULL; 683 for (linkNum = linksSeen = 0; linksSeen <= priv->numLinks; linkNum++) { 684 struct ng_bridge_link *destLink; 685 struct mbuf *m2 = NULL; 686 687 /* 688 * If we have checked all the links then now 689 * send the original on its reserved link 690 */ 691 if (linksSeen == priv->numLinks) { 692 /* If we never saw a good link, leave. */ 693 if (firstLink == NULL) { 694 NG_FREE_ITEM(item); 695 NG_FREE_M(m); 696 return (0); 697 } 698 destLink = firstLink; 699 } else { 700 destLink = priv->links[linkNum]; 701 if (destLink != NULL) 702 linksSeen++; 703 /* Skip incoming link and disconnected links */ 704 if (destLink == NULL || destLink == link) { 705 continue; 706 } 707 if (firstLink == NULL) { 708 /* 709 * This is the first usable link we have found. 710 * Reserve it for the originals. 711 * If we never find another we save a copy. 712 */ 713 firstLink = destLink; 714 continue; 715 } 716 717 /* 718 * It's usable link but not the reserved (first) one. 719 * Copy mbuf info for sending. 720 */ 721 m2 = m_dup(m, M_DONTWAIT); /* XXX m_copypacket() */ 722 if (m2 == NULL) { 723 link->stats.memoryFailures++; 724 NG_FREE_ITEM(item); 725 NG_FREE_M(m); 726 return (ENOBUFS); 727 } 728 } 729 730 /* Update stats */ 731 destLink->stats.xmitPackets++; 732 destLink->stats.xmitOctets += m->m_pkthdr.len; 733 switch (manycast) { 734 case 0: /* unicast */ 735 break; 736 case 1: /* multicast */ 737 destLink->stats.xmitMulticasts++; 738 break; 739 case 2: /* broadcast */ 740 destLink->stats.xmitBroadcasts++; 741 break; 742 } 743 744 /* Send packet */ 745 if (destLink == firstLink) { 746 /* 747 * If we've sent all the others, send the original 748 * on the first link we found. 749 */ 750 NG_FWD_NEW_DATA(error, item, destLink->hook, m); 751 break; /* always done last - not really needed. */ 752 } else { 753 NG_SEND_DATA_ONLY(error, destLink->hook, m2); 754 } 755 } 756 return (error); 757 } 758 759 /* 760 * Shutdown node 761 */ 762 static int 763 ng_bridge_shutdown(node_p node) 764 { 765 const priv_p priv = NG_NODE_PRIVATE(node); 766 767 /* 768 * Shut down everything including the timer. Even if the 769 * callout has already been dequeued and is about to be 770 * run, ng_bridge_timeout() won't be fired as the node 771 * is already marked NGF_INVALID, so we're safe to free 772 * the node now. 773 */ 774 KASSERT(priv->numLinks == 0 && priv->numHosts == 0, 775 ("%s: numLinks=%d numHosts=%d", 776 __func__, priv->numLinks, priv->numHosts)); 777 ng_uncallout(&priv->timer, node); 778 NG_NODE_SET_PRIVATE(node, NULL); 779 NG_NODE_UNREF(node); 780 free(priv->tab, M_NETGRAPH_BRIDGE); 781 free(priv, M_NETGRAPH_BRIDGE); 782 return (0); 783 } 784 785 /* 786 * Hook disconnection. 787 */ 788 static int 789 ng_bridge_disconnect(hook_p hook) 790 { 791 const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook)); 792 int linkNum; 793 794 /* Get link number */ 795 linkNum = (intptr_t)NG_HOOK_PRIVATE(hook); 796 KASSERT(linkNum >= 0 && linkNum < NG_BRIDGE_MAX_LINKS, 797 ("%s: linkNum=%u", __func__, linkNum)); 798 799 /* Remove all hosts associated with this link */ 800 ng_bridge_remove_hosts(priv, linkNum); 801 802 /* Free associated link information */ 803 KASSERT(priv->links[linkNum] != NULL, ("%s: no link", __func__)); 804 free(priv->links[linkNum], M_NETGRAPH_BRIDGE); 805 priv->links[linkNum] = NULL; 806 priv->numLinks--; 807 808 /* If no more hooks, go away */ 809 if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0) 810 && (NG_NODE_IS_VALID(NG_HOOK_NODE(hook))) 811 && !priv->persistent) { 812 ng_rmnode_self(NG_HOOK_NODE(hook)); 813 } 814 return (0); 815 } 816 817 /****************************************************************** 818 HASH TABLE FUNCTIONS 819 ******************************************************************/ 820 821 /* 822 * Hash algorithm 823 */ 824 #define HASH(addr,mask) ( (((const u_int16_t *)(addr))[0] \ 825 ^ ((const u_int16_t *)(addr))[1] \ 826 ^ ((const u_int16_t *)(addr))[2]) & (mask) ) 827 828 /* 829 * Find a host entry in the table. 830 */ 831 static struct ng_bridge_host * 832 ng_bridge_get(priv_p priv, const u_char *addr) 833 { 834 const int bucket = HASH(addr, priv->hashMask); 835 struct ng_bridge_hent *hent; 836 837 SLIST_FOREACH(hent, &priv->tab[bucket], next) { 838 if (ETHER_EQUAL(hent->host.addr, addr)) 839 return (&hent->host); 840 } 841 return (NULL); 842 } 843 844 /* 845 * Add a new host entry to the table. This assumes the host doesn't 846 * already exist in the table. Returns 1 on success, 0 if there 847 * was a memory allocation failure. 848 */ 849 static int 850 ng_bridge_put(priv_p priv, const u_char *addr, int linkNum) 851 { 852 const int bucket = HASH(addr, priv->hashMask); 853 struct ng_bridge_hent *hent; 854 855 #ifdef INVARIANTS 856 /* Assert that entry does not already exist in hashtable */ 857 SLIST_FOREACH(hent, &priv->tab[bucket], next) { 858 KASSERT(!ETHER_EQUAL(hent->host.addr, addr), 859 ("%s: entry %6D exists in table", __func__, addr, ":")); 860 } 861 #endif 862 863 /* Allocate and initialize new hashtable entry */ 864 hent = malloc(sizeof(*hent), M_NETGRAPH_BRIDGE, M_NOWAIT); 865 if (hent == NULL) 866 return (0); 867 bcopy(addr, hent->host.addr, ETHER_ADDR_LEN); 868 hent->host.linkNum = linkNum; 869 hent->host.staleness = 0; 870 hent->host.age = 0; 871 872 /* Add new element to hash bucket */ 873 SLIST_INSERT_HEAD(&priv->tab[bucket], hent, next); 874 priv->numHosts++; 875 876 /* Resize table if necessary */ 877 ng_bridge_rehash(priv); 878 return (1); 879 } 880 881 /* 882 * Resize the hash table. We try to maintain the number of buckets 883 * such that the load factor is in the range 0.25 to 1.0. 884 * 885 * If we can't get the new memory then we silently fail. This is OK 886 * because things will still work and we'll try again soon anyway. 887 */ 888 static void 889 ng_bridge_rehash(priv_p priv) 890 { 891 struct ng_bridge_bucket *newTab; 892 int oldBucket, newBucket; 893 int newNumBuckets; 894 u_int newMask; 895 896 /* Is table too full or too empty? */ 897 if (priv->numHosts > priv->numBuckets 898 && (priv->numBuckets << 1) <= MAX_BUCKETS) 899 newNumBuckets = priv->numBuckets << 1; 900 else if (priv->numHosts < (priv->numBuckets >> 2) 901 && (priv->numBuckets >> 2) >= MIN_BUCKETS) 902 newNumBuckets = priv->numBuckets >> 2; 903 else 904 return; 905 newMask = newNumBuckets - 1; 906 907 /* Allocate and initialize new table */ 908 newTab = malloc(newNumBuckets * sizeof(*newTab), 909 M_NETGRAPH_BRIDGE, M_NOWAIT | M_ZERO); 910 if (newTab == NULL) 911 return; 912 913 /* Move all entries from old table to new table */ 914 for (oldBucket = 0; oldBucket < priv->numBuckets; oldBucket++) { 915 struct ng_bridge_bucket *const oldList = &priv->tab[oldBucket]; 916 917 while (!SLIST_EMPTY(oldList)) { 918 struct ng_bridge_hent *const hent 919 = SLIST_FIRST(oldList); 920 921 SLIST_REMOVE_HEAD(oldList, next); 922 newBucket = HASH(hent->host.addr, newMask); 923 SLIST_INSERT_HEAD(&newTab[newBucket], hent, next); 924 } 925 } 926 927 /* Replace old table with new one */ 928 if (priv->conf.debugLevel >= 3) { 929 log(LOG_INFO, "ng_bridge: %s: table size %d -> %d\n", 930 ng_bridge_nodename(priv->node), 931 priv->numBuckets, newNumBuckets); 932 } 933 free(priv->tab, M_NETGRAPH_BRIDGE); 934 priv->numBuckets = newNumBuckets; 935 priv->hashMask = newMask; 936 priv->tab = newTab; 937 return; 938 } 939 940 /****************************************************************** 941 MISC FUNCTIONS 942 ******************************************************************/ 943 944 /* 945 * Remove all hosts associated with a specific link from the hashtable. 946 * If linkNum == -1, then remove all hosts in the table. 947 */ 948 static void 949 ng_bridge_remove_hosts(priv_p priv, int linkNum) 950 { 951 int bucket; 952 953 for (bucket = 0; bucket < priv->numBuckets; bucket++) { 954 struct ng_bridge_hent **hptr = &SLIST_FIRST(&priv->tab[bucket]); 955 956 while (*hptr != NULL) { 957 struct ng_bridge_hent *const hent = *hptr; 958 959 if (linkNum == -1 || hent->host.linkNum == linkNum) { 960 *hptr = SLIST_NEXT(hent, next); 961 free(hent, M_NETGRAPH_BRIDGE); 962 priv->numHosts--; 963 } else 964 hptr = &SLIST_NEXT(hent, next); 965 } 966 } 967 } 968 969 /* 970 * Handle our once-per-second timeout event. We do two things: 971 * we decrement link->loopCount for those links being muted due to 972 * a detected loopback condition, and we remove any hosts from 973 * the hashtable whom we haven't heard from in a long while. 974 */ 975 static void 976 ng_bridge_timeout(node_p node, hook_p hook, void *arg1, int arg2) 977 { 978 const priv_p priv = NG_NODE_PRIVATE(node); 979 int bucket; 980 int counter = 0; 981 int linkNum; 982 983 /* Update host time counters and remove stale entries */ 984 for (bucket = 0; bucket < priv->numBuckets; bucket++) { 985 struct ng_bridge_hent **hptr = &SLIST_FIRST(&priv->tab[bucket]); 986 987 while (*hptr != NULL) { 988 struct ng_bridge_hent *const hent = *hptr; 989 990 /* Make sure host's link really exists */ 991 KASSERT(priv->links[hent->host.linkNum] != NULL, 992 ("%s: host %6D on nonexistent link %d\n", 993 __func__, hent->host.addr, ":", 994 hent->host.linkNum)); 995 996 /* Remove hosts we haven't heard from in a while */ 997 if (++hent->host.staleness >= priv->conf.maxStaleness) { 998 *hptr = SLIST_NEXT(hent, next); 999 free(hent, M_NETGRAPH_BRIDGE); 1000 priv->numHosts--; 1001 } else { 1002 if (hent->host.age < 0xffff) 1003 hent->host.age++; 1004 hptr = &SLIST_NEXT(hent, next); 1005 counter++; 1006 } 1007 } 1008 } 1009 KASSERT(priv->numHosts == counter, 1010 ("%s: hosts: %d != %d", __func__, priv->numHosts, counter)); 1011 1012 /* Decrease table size if necessary */ 1013 ng_bridge_rehash(priv); 1014 1015 /* Decrease loop counter on muted looped back links */ 1016 for (counter = linkNum = 0; linkNum < NG_BRIDGE_MAX_LINKS; linkNum++) { 1017 struct ng_bridge_link *const link = priv->links[linkNum]; 1018 1019 if (link != NULL) { 1020 if (link->loopCount != 0) { 1021 link->loopCount--; 1022 if (link->loopCount == 0 1023 && priv->conf.debugLevel >= 2) { 1024 log(LOG_INFO, "ng_bridge: %s:" 1025 " restoring looped back link%d\n", 1026 ng_bridge_nodename(node), linkNum); 1027 } 1028 } 1029 counter++; 1030 } 1031 } 1032 KASSERT(priv->numLinks == counter, 1033 ("%s: links: %d != %d", __func__, priv->numLinks, counter)); 1034 1035 /* Register a new timeout, keeping the existing node reference */ 1036 ng_callout(&priv->timer, node, NULL, hz, ng_bridge_timeout, NULL, 0); 1037 } 1038 1039 /* 1040 * Return node's "name", even if it doesn't have one. 1041 */ 1042 static const char * 1043 ng_bridge_nodename(node_p node) 1044 { 1045 static char name[NG_NODESIZ]; 1046 1047 if (NG_NODE_NAME(node) != NULL) 1048 snprintf(name, sizeof(name), "%s", NG_NODE_NAME(node)); 1049 else 1050 snprintf(name, sizeof(name), "[%x]", ng_node2ID(node)); 1051 return name; 1052 } 1053
Cache object: 366a3cc7dfbf990ef8348913aa1ae900
[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]