1 /*- 2 * Copyright (c) 2000 Whistle Communications, Inc. 3 * All rights reserved. 4 * 5 * Subject to the following obligations and disclaimer of warranty, use and 6 * redistribution of this software, in source or object code forms, with or 7 * without modifications are expressly permitted by Whistle Communications; 8 * provided, however, that: 9 * 1. Any and all reproductions of the source or object code must include the 10 * copyright notice above and the following disclaimer of warranties; and 11 * 2. No rights are granted, in any manner or form, to use Whistle 12 * Communications, Inc. trademarks, including the mark "WHISTLE 13 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as 14 * such appears in the above copyright notice or in the software. 15 * 16 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND 17 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO 18 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE, 19 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF 20 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. 21 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY 22 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS 23 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE. 24 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES 25 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING 26 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 27 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR 28 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY 29 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 30 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 31 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY 32 * OF SUCH DAMAGE. 33 * 34 * Author: Archie Cobbs <archie@freebsd.org> 35 */ 36 37 /* 38 * ng_bridge(4) netgraph node type 39 * 40 * The node performs standard intelligent Ethernet bridging over 41 * each of its connected hooks, or links. A simple loop detection 42 * algorithm is included which disables a link for priv->conf.loopTimeout 43 * seconds when a host is seen to have jumped from one link to 44 * another within priv->conf.minStableAge seconds. 45 * 46 * We keep a hashtable that maps Ethernet addresses to host info, 47 * which is contained in struct ng_bridge_host's. These structures 48 * tell us on which link the host may be found. A host's entry will 49 * expire after priv->conf.maxStaleness seconds. 50 * 51 * This node is optimzed for stable networks, where machines jump 52 * from one port to the other only rarely. 53 */ 54 55 #include <sys/param.h> 56 #include <sys/systm.h> 57 #include <sys/kernel.h> 58 #include <sys/lock.h> 59 #include <sys/malloc.h> 60 #include <sys/mbuf.h> 61 #include <sys/errno.h> 62 #include <sys/rwlock.h> 63 #include <sys/syslog.h> 64 #include <sys/socket.h> 65 #include <sys/ctype.h> 66 #include <sys/types.h> 67 #include <sys/counter.h> 68 69 #include <net/if.h> 70 #include <net/if_var.h> 71 #include <net/ethernet.h> 72 #include <net/vnet.h> 73 74 #include <netinet/in.h> 75 #include <netgraph/ng_message.h> 76 #include <netgraph/netgraph.h> 77 #include <netgraph/ng_parse.h> 78 #include <netgraph/ng_bridge.h> 79 80 #ifdef NG_SEPARATE_MALLOC 81 static MALLOC_DEFINE(M_NETGRAPH_BRIDGE, "netgraph_bridge", 82 "netgraph bridge node"); 83 #else 84 #define M_NETGRAPH_BRIDGE M_NETGRAPH 85 #endif 86 87 /* Counter based stats */ 88 struct ng_bridge_link_kernel_stats { 89 counter_u64_t recvOctets; /* total octets rec'd on link */ 90 counter_u64_t recvPackets; /* total pkts rec'd on link */ 91 counter_u64_t recvMulticasts; /* multicast pkts rec'd on link */ 92 counter_u64_t recvBroadcasts; /* broadcast pkts rec'd on link */ 93 counter_u64_t recvUnknown; /* pkts rec'd with unknown dest addr */ 94 counter_u64_t recvRunts; /* pkts rec'd less than 14 bytes */ 95 counter_u64_t recvInvalid; /* pkts rec'd with bogus source addr */ 96 counter_u64_t xmitOctets; /* total octets xmit'd on link */ 97 counter_u64_t xmitPackets; /* total pkts xmit'd on link */ 98 counter_u64_t xmitMulticasts; /* multicast pkts xmit'd on link */ 99 counter_u64_t xmitBroadcasts; /* broadcast pkts xmit'd on link */ 100 counter_u64_t loopDrops; /* pkts dropped due to loopback */ 101 u_int64_t loopDetects; /* number of loop detections */ 102 counter_u64_t memoryFailures; /* times couldn't get mem or mbuf */ 103 }; 104 105 /* Per-link private data */ 106 struct ng_bridge_link { 107 hook_p hook; /* netgraph hook */ 108 u_int16_t loopCount; /* loop ignore timer */ 109 unsigned int learnMac : 1, /* autolearn macs */ 110 sendUnknown : 1;/* send unknown macs out */ 111 struct ng_bridge_link_kernel_stats stats; /* link stats */ 112 }; 113 typedef struct ng_bridge_link const *link_cp; /* read only access */ 114 115 /* Per-node private data */ 116 struct ng_bridge_private { 117 struct ng_bridge_bucket *tab; /* hash table bucket array */ 118 struct ng_bridge_config conf; /* node configuration */ 119 node_p node; /* netgraph node */ 120 u_int numHosts; /* num entries in table */ 121 u_int numBuckets; /* num buckets in table */ 122 u_int hashMask; /* numBuckets - 1 */ 123 int numLinks; /* num connected links */ 124 unsigned int persistent : 1, /* can exist w/o hooks */ 125 sendUnknown : 1;/* links receive unknowns by default */ 126 struct callout timer; /* one second periodic timer */ 127 }; 128 typedef struct ng_bridge_private *priv_p; 129 typedef struct ng_bridge_private const *priv_cp; /* read only access */ 130 131 /* Information about a host, stored in a hash table entry */ 132 struct ng_bridge_host { 133 u_char addr[6]; /* ethernet address */ 134 link_p link; /* link where addr can be found */ 135 u_int16_t age; /* seconds ago entry was created */ 136 u_int16_t staleness; /* seconds ago host last heard from */ 137 SLIST_ENTRY(ng_bridge_host) next; /* next entry in bucket */ 138 }; 139 140 /* Hash table bucket declaration */ 141 SLIST_HEAD(ng_bridge_bucket, ng_bridge_host); 142 143 /* Netgraph node methods */ 144 static ng_constructor_t ng_bridge_constructor; 145 static ng_rcvmsg_t ng_bridge_rcvmsg; 146 static ng_shutdown_t ng_bridge_shutdown; 147 static ng_newhook_t ng_bridge_newhook; 148 static ng_rcvdata_t ng_bridge_rcvdata; 149 static ng_disconnect_t ng_bridge_disconnect; 150 151 /* Other internal functions */ 152 static void ng_bridge_free_link(link_p link); 153 static struct ng_bridge_host *ng_bridge_get(priv_cp priv, const u_char *addr); 154 static int ng_bridge_put(priv_p priv, const u_char *addr, link_p link); 155 static void ng_bridge_rehash(priv_p priv); 156 static void ng_bridge_remove_hosts(priv_p priv, link_p link); 157 static void ng_bridge_timeout(node_p node, hook_p hook, void *arg1, int arg2); 158 static const char *ng_bridge_nodename(node_cp node); 159 160 /* Ethernet broadcast */ 161 static const u_char ng_bridge_bcast_addr[ETHER_ADDR_LEN] = 162 { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; 163 164 /* Compare Ethernet addresses using 32 and 16 bit words instead of bytewise */ 165 #define ETHER_EQUAL(a,b) (((const u_int32_t *)(a))[0] \ 166 == ((const u_int32_t *)(b))[0] \ 167 && ((const u_int16_t *)(a))[2] \ 168 == ((const u_int16_t *)(b))[2]) 169 170 /* Minimum and maximum number of hash buckets. Must be a power of two. */ 171 #define MIN_BUCKETS (1 << 5) /* 32 */ 172 #define MAX_BUCKETS (1 << 14) /* 16384 */ 173 174 /* Configuration default values */ 175 #define DEFAULT_LOOP_TIMEOUT 60 176 #define DEFAULT_MAX_STALENESS (15 * 60) /* same as ARP timeout */ 177 #define DEFAULT_MIN_STABLE_AGE 1 178 179 /****************************************************************** 180 NETGRAPH PARSE TYPES 181 ******************************************************************/ 182 183 /* 184 * How to determine the length of the table returned by NGM_BRIDGE_GET_TABLE 185 */ 186 static int 187 ng_bridge_getTableLength(const struct ng_parse_type *type, 188 const u_char *start, const u_char *buf) 189 { 190 const struct ng_bridge_host_ary *const hary 191 = (const struct ng_bridge_host_ary *)(buf - sizeof(u_int32_t)); 192 193 return hary->numHosts; 194 } 195 196 /* Parse type for struct ng_bridge_host_ary */ 197 static const struct ng_parse_struct_field ng_bridge_host_type_fields[] 198 = NG_BRIDGE_HOST_TYPE_INFO(&ng_parse_enaddr_type); 199 static const struct ng_parse_type ng_bridge_host_type = { 200 &ng_parse_struct_type, 201 &ng_bridge_host_type_fields 202 }; 203 static const struct ng_parse_array_info ng_bridge_hary_type_info = { 204 &ng_bridge_host_type, 205 ng_bridge_getTableLength 206 }; 207 static const struct ng_parse_type ng_bridge_hary_type = { 208 &ng_parse_array_type, 209 &ng_bridge_hary_type_info 210 }; 211 static const struct ng_parse_struct_field ng_bridge_host_ary_type_fields[] 212 = NG_BRIDGE_HOST_ARY_TYPE_INFO(&ng_bridge_hary_type); 213 static const struct ng_parse_type ng_bridge_host_ary_type = { 214 &ng_parse_struct_type, 215 &ng_bridge_host_ary_type_fields 216 }; 217 218 /* Parse type for struct ng_bridge_config */ 219 static const struct ng_parse_struct_field ng_bridge_config_type_fields[] 220 = NG_BRIDGE_CONFIG_TYPE_INFO; 221 static const struct ng_parse_type ng_bridge_config_type = { 222 &ng_parse_struct_type, 223 &ng_bridge_config_type_fields 224 }; 225 226 /* Parse type for struct ng_bridge_link_stat */ 227 static const struct ng_parse_struct_field ng_bridge_stats_type_fields[] 228 = NG_BRIDGE_STATS_TYPE_INFO; 229 static const struct ng_parse_type ng_bridge_stats_type = { 230 &ng_parse_struct_type, 231 &ng_bridge_stats_type_fields 232 }; 233 /* Parse type for struct ng_bridge_move_host */ 234 static const struct ng_parse_struct_field ng_bridge_move_host_type_fields[] 235 = NG_BRIDGE_MOVE_HOST_TYPE_INFO(&ng_parse_enaddr_type); 236 static const struct ng_parse_type ng_bridge_move_host_type = { 237 &ng_parse_struct_type, 238 &ng_bridge_move_host_type_fields 239 }; 240 241 /* List of commands and how to convert arguments to/from ASCII */ 242 static const struct ng_cmdlist ng_bridge_cmdlist[] = { 243 { 244 NGM_BRIDGE_COOKIE, 245 NGM_BRIDGE_SET_CONFIG, 246 "setconfig", 247 &ng_bridge_config_type, 248 NULL 249 }, 250 { 251 NGM_BRIDGE_COOKIE, 252 NGM_BRIDGE_GET_CONFIG, 253 "getconfig", 254 NULL, 255 &ng_bridge_config_type 256 }, 257 { 258 NGM_BRIDGE_COOKIE, 259 NGM_BRIDGE_RESET, 260 "reset", 261 NULL, 262 NULL 263 }, 264 { 265 NGM_BRIDGE_COOKIE, 266 NGM_BRIDGE_GET_STATS, 267 "getstats", 268 &ng_parse_uint32_type, 269 &ng_bridge_stats_type 270 }, 271 { 272 NGM_BRIDGE_COOKIE, 273 NGM_BRIDGE_CLR_STATS, 274 "clrstats", 275 &ng_parse_uint32_type, 276 NULL 277 }, 278 { 279 NGM_BRIDGE_COOKIE, 280 NGM_BRIDGE_GETCLR_STATS, 281 "getclrstats", 282 &ng_parse_uint32_type, 283 &ng_bridge_stats_type 284 }, 285 { 286 NGM_BRIDGE_COOKIE, 287 NGM_BRIDGE_GET_TABLE, 288 "gettable", 289 NULL, 290 &ng_bridge_host_ary_type 291 }, 292 { 293 NGM_BRIDGE_COOKIE, 294 NGM_BRIDGE_SET_PERSISTENT, 295 "setpersistent", 296 NULL, 297 NULL 298 }, 299 { 300 NGM_BRIDGE_COOKIE, 301 NGM_BRIDGE_MOVE_HOST, 302 "movehost", 303 &ng_bridge_move_host_type, 304 NULL 305 }, 306 { 0 } 307 }; 308 309 /* Node type descriptor */ 310 static struct ng_type ng_bridge_typestruct = { 311 .version = NG_ABI_VERSION, 312 .name = NG_BRIDGE_NODE_TYPE, 313 .constructor = ng_bridge_constructor, 314 .rcvmsg = ng_bridge_rcvmsg, 315 .shutdown = ng_bridge_shutdown, 316 .newhook = ng_bridge_newhook, 317 .rcvdata = ng_bridge_rcvdata, 318 .disconnect = ng_bridge_disconnect, 319 .cmdlist = ng_bridge_cmdlist, 320 }; 321 NETGRAPH_INIT(bridge, &ng_bridge_typestruct); 322 323 /****************************************************************** 324 NETGRAPH NODE METHODS 325 ******************************************************************/ 326 327 /* 328 * Node constructor 329 */ 330 static int 331 ng_bridge_constructor(node_p node) 332 { 333 priv_p priv; 334 335 /* Allocate and initialize private info */ 336 priv = malloc(sizeof(*priv), M_NETGRAPH_BRIDGE, M_WAITOK | M_ZERO); 337 ng_callout_init(&priv->timer); 338 339 /* Allocate and initialize hash table, etc. */ 340 priv->tab = malloc(MIN_BUCKETS * sizeof(*priv->tab), 341 M_NETGRAPH_BRIDGE, M_WAITOK | M_ZERO); 342 priv->numBuckets = MIN_BUCKETS; 343 priv->hashMask = MIN_BUCKETS - 1; 344 priv->conf.debugLevel = 1; 345 priv->conf.loopTimeout = DEFAULT_LOOP_TIMEOUT; 346 priv->conf.maxStaleness = DEFAULT_MAX_STALENESS; 347 priv->conf.minStableAge = DEFAULT_MIN_STABLE_AGE; 348 priv->sendUnknown = 1; /* classic bridge */ 349 350 NG_NODE_SET_PRIVATE(node, priv); 351 priv->node = node; 352 353 /* Start timer; timer is always running while node is alive */ 354 ng_callout(&priv->timer, node, NULL, hz, ng_bridge_timeout, NULL, 0); 355 356 /* Done */ 357 return (0); 358 } 359 360 /* 361 * Method for attaching a new hook 362 */ 363 static int 364 ng_bridge_newhook(node_p node, hook_p hook, const char *name) 365 { 366 const priv_p priv = NG_NODE_PRIVATE(node); 367 char linkName[NG_HOOKSIZ]; 368 u_int32_t linkNum; 369 link_p link; 370 const char *prefix = NG_BRIDGE_HOOK_LINK_PREFIX; 371 bool isUplink; 372 373 /* Check for a link hook */ 374 if (strlen(name) <= strlen(prefix)) 375 return (EINVAL); /* Unknown hook name */ 376 377 isUplink = (name[0] == 'u'); 378 if (isUplink) 379 prefix = NG_BRIDGE_HOOK_UPLINK_PREFIX; 380 381 /* primitive parsing */ 382 linkNum = strtoul(name + strlen(prefix), NULL, 10); 383 /* validation by comparing against the reconstucted name */ 384 snprintf(linkName, sizeof(linkName), "%s%u", prefix, linkNum); 385 if (strcmp(linkName, name) != 0) 386 return (EINVAL); 387 388 if (linkNum == 0 && isUplink) 389 return (EINVAL); 390 391 if(NG_PEER_NODE(hook) == node) 392 return (ELOOP); 393 394 link = malloc(sizeof(*link), M_NETGRAPH_BRIDGE, M_NOWAIT | M_ZERO); 395 if (link == NULL) 396 return (ENOMEM); 397 398 #define NG_BRIDGE_COUNTER_ALLOC(f) do { \ 399 link->stats.f = counter_u64_alloc(M_NOWAIT); \ 400 if (link->stats.f == NULL) \ 401 goto nomem; \ 402 } while (0) 403 NG_BRIDGE_COUNTER_ALLOC(recvOctets); 404 NG_BRIDGE_COUNTER_ALLOC(recvPackets); 405 NG_BRIDGE_COUNTER_ALLOC(recvMulticasts); 406 NG_BRIDGE_COUNTER_ALLOC(recvBroadcasts); 407 NG_BRIDGE_COUNTER_ALLOC(recvUnknown); 408 NG_BRIDGE_COUNTER_ALLOC(recvRunts); 409 NG_BRIDGE_COUNTER_ALLOC(recvInvalid); 410 NG_BRIDGE_COUNTER_ALLOC(xmitOctets); 411 NG_BRIDGE_COUNTER_ALLOC(xmitPackets); 412 NG_BRIDGE_COUNTER_ALLOC(xmitMulticasts); 413 NG_BRIDGE_COUNTER_ALLOC(xmitBroadcasts); 414 NG_BRIDGE_COUNTER_ALLOC(loopDrops); 415 NG_BRIDGE_COUNTER_ALLOC(memoryFailures); 416 #undef NG_BRIDGE_COUNTER_ALLOC 417 418 link->hook = hook; 419 if (isUplink) { 420 link->learnMac = 0; 421 link->sendUnknown = 1; 422 if (priv->numLinks == 0) /* if the first link is an uplink */ 423 priv->sendUnknown = 0; /* switch to restrictive mode */ 424 } else { 425 link->learnMac = 1; 426 link->sendUnknown = priv->sendUnknown; 427 } 428 429 NG_HOOK_SET_PRIVATE(hook, link); 430 priv->numLinks++; 431 return (0); 432 433 nomem: 434 ng_bridge_free_link(link); 435 return (ENOMEM); 436 } 437 438 /* 439 * Receive a control message 440 */ 441 static void 442 ng_bridge_clear_link_stats(struct ng_bridge_link_kernel_stats *p) 443 { 444 counter_u64_zero(p->recvOctets); 445 counter_u64_zero(p->recvPackets); 446 counter_u64_zero(p->recvMulticasts); 447 counter_u64_zero(p->recvBroadcasts); 448 counter_u64_zero(p->recvUnknown); 449 counter_u64_zero(p->recvRunts); 450 counter_u64_zero(p->recvInvalid); 451 counter_u64_zero(p->xmitOctets); 452 counter_u64_zero(p->xmitPackets); 453 counter_u64_zero(p->xmitMulticasts); 454 counter_u64_zero(p->xmitBroadcasts); 455 counter_u64_zero(p->loopDrops); 456 p->loopDetects = 0; 457 counter_u64_zero(p->memoryFailures); 458 } 459 460 static void 461 ng_bridge_free_link(link_p link) 462 { 463 counter_u64_free(link->stats.recvOctets); 464 counter_u64_free(link->stats.recvPackets); 465 counter_u64_free(link->stats.recvMulticasts); 466 counter_u64_free(link->stats.recvBroadcasts); 467 counter_u64_free(link->stats.recvUnknown); 468 counter_u64_free(link->stats.recvRunts); 469 counter_u64_free(link->stats.recvInvalid); 470 counter_u64_free(link->stats.xmitOctets); 471 counter_u64_free(link->stats.xmitPackets); 472 counter_u64_free(link->stats.xmitMulticasts); 473 counter_u64_free(link->stats.xmitBroadcasts); 474 counter_u64_free(link->stats.loopDrops); 475 counter_u64_free(link->stats.memoryFailures); 476 free(link, M_NETGRAPH_BRIDGE); 477 } 478 479 static int 480 ng_bridge_reset_link(hook_p hook, void *arg __unused) 481 { 482 link_p priv = NG_HOOK_PRIVATE(hook); 483 484 priv->loopCount = 0; 485 ng_bridge_clear_link_stats(&priv->stats); 486 return (1); 487 } 488 489 static int 490 ng_bridge_rcvmsg(node_p node, item_p item, hook_p lasthook) 491 { 492 const priv_p priv = NG_NODE_PRIVATE(node); 493 struct ng_mesg *resp = NULL; 494 int error = 0; 495 struct ng_mesg *msg; 496 497 NGI_GET_MSG(item, msg); 498 switch (msg->header.typecookie) { 499 case NGM_BRIDGE_COOKIE: 500 switch (msg->header.cmd) { 501 case NGM_BRIDGE_GET_CONFIG: 502 { 503 struct ng_bridge_config *conf; 504 505 NG_MKRESPONSE(resp, msg, 506 sizeof(struct ng_bridge_config), M_NOWAIT); 507 if (resp == NULL) { 508 error = ENOMEM; 509 break; 510 } 511 conf = (struct ng_bridge_config *)resp->data; 512 *conf = priv->conf; /* no sanity checking needed */ 513 break; 514 } 515 case NGM_BRIDGE_SET_CONFIG: 516 { 517 struct ng_bridge_config *conf; 518 519 if (msg->header.arglen 520 != sizeof(struct ng_bridge_config)) { 521 error = EINVAL; 522 break; 523 } 524 conf = (struct ng_bridge_config *)msg->data; 525 priv->conf = *conf; 526 break; 527 } 528 case NGM_BRIDGE_RESET: 529 { 530 /* Flush all entries in the hash table */ 531 ng_bridge_remove_hosts(priv, NULL); 532 533 /* Reset all loop detection counters and stats */ 534 NG_NODE_FOREACH_HOOK(node, ng_bridge_reset_link, NULL); 535 break; 536 } 537 case NGM_BRIDGE_GET_STATS: 538 case NGM_BRIDGE_CLR_STATS: 539 case NGM_BRIDGE_GETCLR_STATS: 540 { 541 hook_p hook; 542 link_p link; 543 char linkName[NG_HOOKSIZ]; 544 int linkNum; 545 546 /* Get link number */ 547 if (msg->header.arglen != sizeof(u_int32_t)) { 548 error = EINVAL; 549 break; 550 } 551 linkNum = *((int32_t *)msg->data); 552 if (linkNum < 0) 553 snprintf(linkName, sizeof(linkName), 554 "%s%u", NG_BRIDGE_HOOK_UPLINK_PREFIX, -linkNum); 555 else 556 snprintf(linkName, sizeof(linkName), 557 "%s%u", NG_BRIDGE_HOOK_LINK_PREFIX, linkNum); 558 559 if ((hook = ng_findhook(node, linkName)) == NULL) { 560 error = ENOTCONN; 561 break; 562 } 563 link = NG_HOOK_PRIVATE(hook); 564 565 /* Get/clear stats */ 566 if (msg->header.cmd != NGM_BRIDGE_CLR_STATS) { 567 struct ng_bridge_link_stats *rs; 568 569 NG_MKRESPONSE(resp, msg, 570 sizeof(link->stats), M_NOWAIT); 571 if (resp == NULL) { 572 error = ENOMEM; 573 break; 574 } 575 rs = (struct ng_bridge_link_stats *)resp->data; 576 #define FETCH(x) rs->x = counter_u64_fetch(link->stats.x) 577 FETCH(recvOctets); 578 FETCH(recvPackets); 579 FETCH(recvMulticasts); 580 FETCH(recvBroadcasts); 581 FETCH(recvUnknown); 582 FETCH(recvRunts); 583 FETCH(recvInvalid); 584 FETCH(xmitOctets); 585 FETCH(xmitPackets); 586 FETCH(xmitMulticasts); 587 FETCH(xmitBroadcasts); 588 FETCH(loopDrops); 589 rs->loopDetects = link->stats.loopDetects; 590 FETCH(memoryFailures); 591 #undef FETCH 592 } 593 if (msg->header.cmd != NGM_BRIDGE_GET_STATS) 594 ng_bridge_clear_link_stats(&link->stats); 595 break; 596 } 597 case NGM_BRIDGE_GET_TABLE: 598 { 599 struct ng_bridge_host_ary *ary; 600 struct ng_bridge_host *host; 601 int i = 0, bucket; 602 603 NG_MKRESPONSE(resp, msg, sizeof(*ary) 604 + (priv->numHosts * sizeof(*ary->hosts)), M_NOWAIT); 605 if (resp == NULL) { 606 error = ENOMEM; 607 break; 608 } 609 ary = (struct ng_bridge_host_ary *)resp->data; 610 ary->numHosts = priv->numHosts; 611 for (bucket = 0; bucket < priv->numBuckets; bucket++) { 612 SLIST_FOREACH(host, &priv->tab[bucket], next) { 613 memcpy(ary->hosts[i].addr, 614 host->addr, 615 sizeof(ary->hosts[i].addr)); 616 ary->hosts[i].age = host->age; 617 ary->hosts[i].staleness = host->staleness; 618 strncpy(ary->hosts[i].hook, 619 NG_HOOK_NAME(host->link->hook), 620 sizeof(ary->hosts[i].hook)); 621 i++; 622 } 623 } 624 break; 625 } 626 case NGM_BRIDGE_SET_PERSISTENT: 627 { 628 priv->persistent = 1; 629 break; 630 } 631 case NGM_BRIDGE_MOVE_HOST: 632 { 633 struct ng_bridge_move_host *mh; 634 hook_p hook; 635 636 if (msg->header.arglen < sizeof(*mh)) { 637 error = EINVAL; 638 break; 639 } 640 mh = (struct ng_bridge_move_host *)msg->data; 641 hook = (mh->hook[0] == 0) 642 ? lasthook 643 : ng_findhook(node, mh->hook); 644 if (hook == NULL) { 645 error = ENOENT; 646 break; 647 } 648 error = ng_bridge_put(priv, mh->addr, NG_HOOK_PRIVATE(hook)); 649 break; 650 } 651 default: 652 error = EINVAL; 653 break; 654 } 655 break; 656 default: 657 error = EINVAL; 658 break; 659 } 660 661 /* Done */ 662 NG_RESPOND_MSG(error, node, item, resp); 663 NG_FREE_MSG(msg); 664 return (error); 665 } 666 667 /* 668 * Receive data on a hook 669 */ 670 struct ng_bridge_send_ctx { 671 link_p foundFirst, incoming; 672 struct mbuf * m; 673 int manycast, error; 674 }; 675 676 /* 677 * Update stats and send out 678 */ 679 static inline int 680 ng_bridge_send_data(link_cp dst, int manycast, struct mbuf *m, item_p item) { 681 int error = 0; 682 size_t len = m->m_pkthdr.len; 683 684 if(item != NULL) 685 NG_FWD_NEW_DATA(error, item, dst->hook, m); 686 else 687 NG_SEND_DATA_ONLY(error, dst->hook, m); 688 689 if (error) { 690 if (error == ENOMEM) 691 counter_u64_add(dst->stats.memoryFailures, 1); 692 /* The packet is still ours */ 693 if (item != NULL) 694 NG_FREE_ITEM(item); 695 if (m != NULL) 696 NG_FREE_M(m); 697 return (error); 698 } 699 700 counter_u64_add(dst->stats.xmitPackets, 1); 701 counter_u64_add(dst->stats.xmitOctets, len); 702 switch (manycast) { 703 default: /* unknown unicast */ 704 break; 705 case 1: /* multicast */ 706 counter_u64_add(dst->stats.xmitMulticasts, 1); 707 break; 708 case 2: /* broadcast */ 709 counter_u64_add(dst->stats.xmitBroadcasts, 1); 710 break; 711 } 712 return (0); 713 } 714 715 /* 716 * Loop body for sending to multiple destinations 717 * return 0 to stop looping 718 */ 719 static int 720 ng_bridge_send_ctx(hook_p dst, void *arg) 721 { 722 struct ng_bridge_send_ctx *ctx = arg; 723 link_p destLink = NG_HOOK_PRIVATE(dst); 724 struct mbuf *m2 = NULL; 725 int error = 0; 726 727 /* Skip incoming link */ 728 if (destLink == ctx->incoming) { 729 return (1); 730 } 731 732 /* Skip sending unknowns to undesired links */ 733 if (!ctx->manycast && !destLink->sendUnknown) 734 return (1); 735 736 if (ctx->foundFirst == NULL) { 737 /* 738 * This is the first usable link we have found. 739 * Reserve it for the originals. 740 * If we never find another we save a copy. 741 */ 742 ctx->foundFirst = destLink; 743 return (1); 744 } 745 746 /* 747 * It's usable link but not the reserved (first) one. 748 * Copy mbuf info for sending. 749 */ 750 m2 = m_dup(ctx->m, M_NOWAIT); 751 if (m2 == NULL) { 752 counter_u64_add(ctx->incoming->stats.memoryFailures, 1); 753 ctx->error = ENOBUFS; 754 return (0); /* abort loop, do not try again and again */ 755 } 756 757 /* Send packet */ 758 error = ng_bridge_send_data(destLink, ctx->manycast, m2, NULL); 759 if (error) 760 ctx->error = error; 761 return (1); 762 } 763 764 static int 765 ng_bridge_rcvdata(hook_p hook, item_p item) 766 { 767 const node_p node = NG_HOOK_NODE(hook); 768 const priv_p priv = NG_NODE_PRIVATE(node); 769 struct ng_bridge_host *host; 770 struct ether_header *eh; 771 struct ng_bridge_send_ctx ctx = { 0 }; 772 773 NGI_GET_M(item, ctx.m); 774 775 ctx.incoming = NG_HOOK_PRIVATE(hook); 776 /* Sanity check packet and pull up header */ 777 if (ctx.m->m_pkthdr.len < ETHER_HDR_LEN) { 778 counter_u64_add(ctx.incoming->stats.recvRunts, 1); 779 NG_FREE_ITEM(item); 780 NG_FREE_M(ctx.m); 781 return (EINVAL); 782 } 783 if (ctx.m->m_len < ETHER_HDR_LEN && !(ctx.m = m_pullup(ctx.m, ETHER_HDR_LEN))) { 784 counter_u64_add(ctx.incoming->stats.memoryFailures, 1); 785 NG_FREE_ITEM(item); 786 return (ENOBUFS); 787 } 788 eh = mtod(ctx.m, struct ether_header *); 789 if ((eh->ether_shost[0] & 1) != 0) { 790 counter_u64_add(ctx.incoming->stats.recvInvalid, 1); 791 NG_FREE_ITEM(item); 792 NG_FREE_M(ctx.m); 793 return (EINVAL); 794 } 795 796 /* Is link disabled due to a loopback condition? */ 797 if (ctx.incoming->loopCount != 0) { 798 counter_u64_add(ctx.incoming->stats.loopDrops, 1); 799 NG_FREE_ITEM(item); 800 NG_FREE_M(ctx.m); 801 return (ELOOP); 802 } 803 804 /* Update stats */ 805 counter_u64_add(ctx.incoming->stats.recvPackets, 1); 806 counter_u64_add(ctx.incoming->stats.recvOctets, ctx.m->m_pkthdr.len); 807 if ((ctx.manycast = (eh->ether_dhost[0] & 1)) != 0) { 808 if (ETHER_EQUAL(eh->ether_dhost, ng_bridge_bcast_addr)) { 809 counter_u64_add(ctx.incoming->stats.recvBroadcasts, 1); 810 ctx.manycast = 2; 811 } else 812 counter_u64_add(ctx.incoming->stats.recvMulticasts, 1); 813 } 814 815 /* Look up packet's source Ethernet address in hashtable */ 816 if ((host = ng_bridge_get(priv, eh->ether_shost)) != NULL) 817 /* Update time since last heard from this host. 818 * This is safe without locking, because it's 819 * the only operation during shared access. 820 */ 821 if (__predict_false(host->staleness > 0)) 822 host->staleness = 0; 823 824 if ((host == NULL && ctx.incoming->learnMac) || 825 (host != NULL && host->link != ctx.incoming)) { 826 struct ng_mesg *msg; 827 struct ng_bridge_move_host *mh; 828 int error = 0; 829 830 NG_MKMESSAGE(msg, NGM_BRIDGE_COOKIE, NGM_BRIDGE_MOVE_HOST, 831 sizeof(*mh), M_NOWAIT); 832 if (msg == NULL) { 833 counter_u64_add(ctx.incoming->stats.memoryFailures, 1); 834 NG_FREE_ITEM(item); 835 NG_FREE_M(ctx.m); 836 return (ENOMEM); 837 } 838 mh = (struct ng_bridge_move_host *)msg->data; 839 strncpy(mh->hook, NG_HOOK_NAME(ctx.incoming->hook), 840 sizeof(mh->hook)); 841 memcpy(mh->addr, eh->ether_shost, sizeof(mh->addr)); 842 NG_SEND_MSG_ID(error, node, msg, NG_NODE_ID(node), 843 NG_NODE_ID(node)); 844 if (error) 845 counter_u64_add(ctx.incoming->stats.memoryFailures, 1); 846 } 847 848 if (host != NULL && host->link != ctx.incoming) { 849 if (host->age < priv->conf.minStableAge) { 850 /* Drop packet on instable links */ 851 counter_u64_add(ctx.incoming->stats.loopDrops, 1); 852 NG_FREE_ITEM(item); 853 NG_FREE_M(ctx.m); 854 return (ELOOP); 855 } 856 } 857 858 /* 859 * If unicast and destination host known, deliver to host's link, 860 * unless it is the same link as the packet came in on. 861 */ 862 if (!ctx.manycast) { 863 /* Determine packet destination link */ 864 if ((host = ng_bridge_get(priv, eh->ether_dhost)) != NULL) { 865 link_p destLink = host->link; 866 867 /* If destination same as incoming link, do nothing */ 868 if (destLink == ctx.incoming) { 869 NG_FREE_ITEM(item); 870 NG_FREE_M(ctx.m); 871 return (0); 872 } 873 874 /* Deliver packet out the destination link */ 875 return (ng_bridge_send_data(destLink, ctx.manycast, ctx.m, item)); 876 } 877 878 /* Destination host is not known */ 879 counter_u64_add(ctx.incoming->stats.recvUnknown, 1); 880 } 881 882 /* Distribute unknown, multicast, broadcast pkts to all other links */ 883 NG_NODE_FOREACH_HOOK(node, ng_bridge_send_ctx, &ctx); 884 885 /* Finally send out on the first link found */ 886 if (ctx.foundFirst != NULL) { 887 int error = ng_bridge_send_data(ctx.foundFirst, ctx.manycast, ctx.m, item); 888 if (error) 889 ctx.error = error; 890 } else { /* nothing to send at all */ 891 NG_FREE_ITEM(item); 892 NG_FREE_M(ctx.m); 893 } 894 895 return (ctx.error); 896 } 897 898 /* 899 * Shutdown node 900 */ 901 static int 902 ng_bridge_shutdown(node_p node) 903 { 904 const priv_p priv = NG_NODE_PRIVATE(node); 905 906 /* 907 * Shut down everything including the timer. Even if the 908 * callout has already been dequeued and is about to be 909 * run, ng_bridge_timeout() won't be fired as the node 910 * is already marked NGF_INVALID, so we're safe to free 911 * the node now. 912 */ 913 KASSERT(priv->numLinks == 0 && priv->numHosts == 0, 914 ("%s: numLinks=%d numHosts=%d", 915 __func__, priv->numLinks, priv->numHosts)); 916 ng_uncallout(&priv->timer, node); 917 NG_NODE_SET_PRIVATE(node, NULL); 918 NG_NODE_UNREF(node); 919 free(priv->tab, M_NETGRAPH_BRIDGE); 920 free(priv, M_NETGRAPH_BRIDGE); 921 return (0); 922 } 923 924 /* 925 * Hook disconnection. 926 */ 927 static int 928 ng_bridge_disconnect(hook_p hook) 929 { 930 const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook)); 931 link_p link = NG_HOOK_PRIVATE(hook); 932 933 /* Remove all hosts associated with this link */ 934 ng_bridge_remove_hosts(priv, link); 935 936 /* Free associated link information */ 937 ng_bridge_free_link(link); 938 priv->numLinks--; 939 940 /* If no more hooks, go away */ 941 if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0) 942 && (NG_NODE_IS_VALID(NG_HOOK_NODE(hook))) 943 && !priv->persistent) { 944 ng_rmnode_self(NG_HOOK_NODE(hook)); 945 } 946 return (0); 947 } 948 949 /****************************************************************** 950 HASH TABLE FUNCTIONS 951 ******************************************************************/ 952 953 /* 954 * Hash algorithm 955 */ 956 #define HASH(addr,mask) ( (((const u_int16_t *)(addr))[0] \ 957 ^ ((const u_int16_t *)(addr))[1] \ 958 ^ ((const u_int16_t *)(addr))[2]) & (mask) ) 959 960 /* 961 * Find a host entry in the table. 962 */ 963 static struct ng_bridge_host * 964 ng_bridge_get(priv_cp priv, const u_char *addr) 965 { 966 const int bucket = HASH(addr, priv->hashMask); 967 struct ng_bridge_host *host; 968 969 SLIST_FOREACH(host, &priv->tab[bucket], next) { 970 if (ETHER_EQUAL(host->addr, addr)) 971 return (host); 972 } 973 return (NULL); 974 } 975 976 /* 977 * Add a host entry to the table. If it already exists, move it 978 * to the new link. Returns 0 on success. 979 */ 980 static int 981 ng_bridge_put(priv_p priv, const u_char *addr, link_p link) 982 { 983 const int bucket = HASH(addr, priv->hashMask); 984 struct ng_bridge_host *host; 985 986 if ((host = ng_bridge_get(priv, addr)) != NULL) { 987 /* Host already on the correct link? */ 988 if (host->link == link) 989 return 0; 990 991 /* Move old host over to new link */ 992 if (host->age >= priv->conf.minStableAge) { 993 host->link = link; 994 host->age = 0; 995 return (0); 996 } 997 /* 998 * If the host was recently moved to the old link and 999 * it's now jumping to a new link, declare a loopback 1000 * condition. 1001 */ 1002 if (priv->conf.debugLevel >= 2) 1003 log(LOG_WARNING, "ng_bridge: %s:" 1004 " loopback detected on %s\n", 1005 ng_bridge_nodename(priv->node), 1006 NG_HOOK_NAME(link->hook)); 1007 1008 /* Mark link as linka non grata */ 1009 link->loopCount = priv->conf.loopTimeout; 1010 link->stats.loopDetects++; 1011 1012 /* Forget all hosts on this link */ 1013 ng_bridge_remove_hosts(priv, link); 1014 return (ELOOP); 1015 } 1016 1017 /* Allocate and initialize new hashtable entry */ 1018 host = malloc(sizeof(*host), M_NETGRAPH_BRIDGE, M_NOWAIT); 1019 if (host == NULL) 1020 return (ENOMEM); 1021 bcopy(addr, host->addr, ETHER_ADDR_LEN); 1022 host->link = link; 1023 host->staleness = 0; 1024 host->age = 0; 1025 1026 /* Add new element to hash bucket */ 1027 SLIST_INSERT_HEAD(&priv->tab[bucket], host, next); 1028 priv->numHosts++; 1029 1030 /* Resize table if necessary */ 1031 ng_bridge_rehash(priv); 1032 return (0); 1033 } 1034 1035 /* 1036 * Resize the hash table. We try to maintain the number of buckets 1037 * such that the load factor is in the range 0.25 to 1.0. 1038 * 1039 * If we can't get the new memory then we silently fail. This is OK 1040 * because things will still work and we'll try again soon anyway. 1041 */ 1042 static void 1043 ng_bridge_rehash(priv_p priv) 1044 { 1045 struct ng_bridge_bucket *newTab; 1046 int oldBucket, newBucket; 1047 int newNumBuckets; 1048 u_int newMask; 1049 1050 /* Is table too full or too empty? */ 1051 if (priv->numHosts > priv->numBuckets 1052 && (priv->numBuckets << 1) <= MAX_BUCKETS) 1053 newNumBuckets = priv->numBuckets << 1; 1054 else if (priv->numHosts < (priv->numBuckets >> 2) 1055 && (priv->numBuckets >> 2) >= MIN_BUCKETS) 1056 newNumBuckets = priv->numBuckets >> 2; 1057 else 1058 return; 1059 newMask = newNumBuckets - 1; 1060 1061 /* Allocate and initialize new table */ 1062 newTab = malloc(newNumBuckets * sizeof(*newTab), 1063 M_NETGRAPH_BRIDGE, M_NOWAIT | M_ZERO); 1064 if (newTab == NULL) 1065 return; 1066 1067 /* Move all entries from old table to new table */ 1068 for (oldBucket = 0; oldBucket < priv->numBuckets; oldBucket++) { 1069 struct ng_bridge_bucket *const oldList = &priv->tab[oldBucket]; 1070 1071 while (!SLIST_EMPTY(oldList)) { 1072 struct ng_bridge_host *const host 1073 = SLIST_FIRST(oldList); 1074 1075 SLIST_REMOVE_HEAD(oldList, next); 1076 newBucket = HASH(host->addr, newMask); 1077 SLIST_INSERT_HEAD(&newTab[newBucket], host, next); 1078 } 1079 } 1080 1081 /* Replace old table with new one */ 1082 if (priv->conf.debugLevel >= 3) { 1083 log(LOG_INFO, "ng_bridge: %s: table size %d -> %d\n", 1084 ng_bridge_nodename(priv->node), 1085 priv->numBuckets, newNumBuckets); 1086 } 1087 free(priv->tab, M_NETGRAPH_BRIDGE); 1088 priv->numBuckets = newNumBuckets; 1089 priv->hashMask = newMask; 1090 priv->tab = newTab; 1091 return; 1092 } 1093 1094 /****************************************************************** 1095 MISC FUNCTIONS 1096 ******************************************************************/ 1097 1098 /* 1099 * Remove all hosts associated with a specific link from the hashtable. 1100 * If linkNum == -1, then remove all hosts in the table. 1101 */ 1102 static void 1103 ng_bridge_remove_hosts(priv_p priv, link_p link) 1104 { 1105 int bucket; 1106 1107 for (bucket = 0; bucket < priv->numBuckets; bucket++) { 1108 struct ng_bridge_host **hptr = &SLIST_FIRST(&priv->tab[bucket]); 1109 1110 while (*hptr != NULL) { 1111 struct ng_bridge_host *const host = *hptr; 1112 1113 if (link == NULL || host->link == link) { 1114 *hptr = SLIST_NEXT(host, next); 1115 free(host, M_NETGRAPH_BRIDGE); 1116 priv->numHosts--; 1117 } else 1118 hptr = &SLIST_NEXT(host, next); 1119 } 1120 } 1121 } 1122 1123 /* 1124 * Handle our once-per-second timeout event. We do two things: 1125 * we decrement link->loopCount for those links being muted due to 1126 * a detected loopback condition, and we remove any hosts from 1127 * the hashtable whom we haven't heard from in a long while. 1128 */ 1129 static int 1130 ng_bridge_unmute(hook_p hook, void *arg) 1131 { 1132 link_p link = NG_HOOK_PRIVATE(hook); 1133 node_p node = NG_HOOK_NODE(hook); 1134 priv_p priv = NG_NODE_PRIVATE(node); 1135 int *counter = arg; 1136 1137 if (link->loopCount != 0) { 1138 link->loopCount--; 1139 if (link->loopCount == 0 && priv->conf.debugLevel >= 2) { 1140 log(LOG_INFO, "ng_bridge: %s:" 1141 " restoring looped back %s\n", 1142 ng_bridge_nodename(node), NG_HOOK_NAME(hook)); 1143 } 1144 } 1145 (*counter)++; 1146 return (1); 1147 } 1148 1149 static void 1150 ng_bridge_timeout(node_p node, hook_p hook, void *arg1, int arg2) 1151 { 1152 const priv_p priv = NG_NODE_PRIVATE(node); 1153 int bucket; 1154 int counter = 0; 1155 1156 /* Update host time counters and remove stale entries */ 1157 for (bucket = 0; bucket < priv->numBuckets; bucket++) { 1158 struct ng_bridge_host **hptr = &SLIST_FIRST(&priv->tab[bucket]); 1159 1160 while (*hptr != NULL) { 1161 struct ng_bridge_host *const host = *hptr; 1162 1163 /* Remove hosts we haven't heard from in a while */ 1164 if (++host->staleness >= priv->conf.maxStaleness) { 1165 *hptr = SLIST_NEXT(host, next); 1166 free(host, M_NETGRAPH_BRIDGE); 1167 priv->numHosts--; 1168 } else { 1169 if (host->age < 0xffff) 1170 host->age++; 1171 hptr = &SLIST_NEXT(host, next); 1172 counter++; 1173 } 1174 } 1175 } 1176 KASSERT(priv->numHosts == counter, 1177 ("%s: hosts: %d != %d", __func__, priv->numHosts, counter)); 1178 1179 /* Decrease table size if necessary */ 1180 ng_bridge_rehash(priv); 1181 1182 /* Decrease loop counter on muted looped back links */ 1183 counter = 0; 1184 NG_NODE_FOREACH_HOOK(node, ng_bridge_unmute, &counter); 1185 KASSERT(priv->numLinks == counter, 1186 ("%s: links: %d != %d", __func__, priv->numLinks, counter)); 1187 1188 /* Register a new timeout, keeping the existing node reference */ 1189 ng_callout(&priv->timer, node, NULL, hz, ng_bridge_timeout, NULL, 0); 1190 } 1191 1192 /* 1193 * Return node's "name", even if it doesn't have one. 1194 */ 1195 static const char * 1196 ng_bridge_nodename(node_cp node) 1197 { 1198 static char name[NG_NODESIZ]; 1199 1200 if (NG_NODE_HAS_NAME(node)) 1201 snprintf(name, sizeof(name), "%s", NG_NODE_NAME(node)); 1202 else 1203 snprintf(name, sizeof(name), "[%x]", ng_node2ID(node)); 1204 return name; 1205 } 1206