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 * $FreeBSD$ 37 */ 38 39 /* 40 * ng_bridge(4) netgraph node type 41 * 42 * The node performs standard intelligent Ethernet bridging over 43 * each of its connected hooks, or links. A simple loop detection 44 * algorithm is included which disables a link for priv->conf.loopTimeout 45 * seconds when a host is seen to have jumped from one link to 46 * another within priv->conf.minStableAge seconds. 47 * 48 * We keep a hashtable that maps Ethernet addresses to host info, 49 * which is contained in struct ng_bridge_host's. These structures 50 * tell us on which link the host may be found. A host's entry will 51 * expire after priv->conf.maxStaleness seconds. 52 * 53 * This node is optimzed for stable networks, where machines jump 54 * from one port to the other only rarely. 55 */ 56 57 #include <sys/param.h> 58 #include <sys/systm.h> 59 #include <sys/kernel.h> 60 #include <sys/lock.h> 61 #include <sys/malloc.h> 62 #include <sys/mbuf.h> 63 #include <sys/errno.h> 64 #include <sys/rwlock.h> 65 #include <sys/syslog.h> 66 #include <sys/socket.h> 67 #include <sys/ctype.h> 68 #include <sys/types.h> 69 #include <sys/counter.h> 70 71 #include <net/if.h> 72 #include <net/if_var.h> 73 #include <net/ethernet.h> 74 #include <net/vnet.h> 75 76 #include <netinet/in.h> 77 #include <netgraph/ng_message.h> 78 #include <netgraph/netgraph.h> 79 #include <netgraph/ng_parse.h> 80 #include <netgraph/ng_bridge.h> 81 82 #ifdef NG_SEPARATE_MALLOC 83 static MALLOC_DEFINE(M_NETGRAPH_BRIDGE, "netgraph_bridge", 84 "netgraph bridge node"); 85 #else 86 #define M_NETGRAPH_BRIDGE M_NETGRAPH 87 #endif 88 89 /* Counter based stats */ 90 struct ng_bridge_link_kernel_stats { 91 counter_u64_t recvOctets; /* total octets rec'd on link */ 92 counter_u64_t recvPackets; /* total pkts rec'd on link */ 93 counter_u64_t recvMulticasts; /* multicast pkts rec'd on link */ 94 counter_u64_t recvBroadcasts; /* broadcast pkts rec'd on link */ 95 counter_u64_t recvUnknown; /* pkts rec'd with unknown dest addr */ 96 counter_u64_t recvRunts; /* pkts rec'd less than 14 bytes */ 97 counter_u64_t recvInvalid; /* pkts rec'd with bogus source addr */ 98 counter_u64_t xmitOctets; /* total octets xmit'd on link */ 99 counter_u64_t xmitPackets; /* total pkts xmit'd on link */ 100 counter_u64_t xmitMulticasts; /* multicast pkts xmit'd on link */ 101 counter_u64_t xmitBroadcasts; /* broadcast pkts xmit'd on link */ 102 counter_u64_t loopDrops; /* pkts dropped due to loopback */ 103 u_int64_t loopDetects; /* number of loop detections */ 104 counter_u64_t memoryFailures; /* times couldn't get mem or mbuf */ 105 }; 106 107 /* Per-link private data */ 108 struct ng_bridge_link { 109 hook_p hook; /* netgraph hook */ 110 u_int16_t loopCount; /* loop ignore timer */ 111 unsigned int learnMac : 1, /* autolearn macs */ 112 sendUnknown : 1;/* send unknown macs out */ 113 struct ng_bridge_link_kernel_stats stats; /* link stats */ 114 }; 115 typedef struct ng_bridge_link const *link_cp; /* read only access */ 116 117 /* Per-node private data */ 118 struct ng_bridge_private { 119 struct ng_bridge_bucket *tab; /* hash table bucket array */ 120 struct ng_bridge_config conf; /* node configuration */ 121 node_p node; /* netgraph node */ 122 u_int numHosts; /* num entries in table */ 123 u_int numBuckets; /* num buckets in table */ 124 u_int hashMask; /* numBuckets - 1 */ 125 int numLinks; /* num connected links */ 126 unsigned int persistent : 1, /* can exist w/o hooks */ 127 sendUnknown : 1;/* links receive unknowns by default */ 128 struct callout timer; /* one second periodic timer */ 129 }; 130 typedef struct ng_bridge_private *priv_p; 131 typedef struct ng_bridge_private const *priv_cp; /* read only access */ 132 133 /* Information about a host, stored in a hash table entry */ 134 struct ng_bridge_host { 135 u_char addr[6]; /* ethernet address */ 136 link_p link; /* link where addr can be found */ 137 u_int16_t age; /* seconds ago entry was created */ 138 u_int16_t staleness; /* seconds ago host last heard from */ 139 SLIST_ENTRY(ng_bridge_host) next; /* next entry in bucket */ 140 }; 141 142 /* Hash table bucket declaration */ 143 SLIST_HEAD(ng_bridge_bucket, ng_bridge_host); 144 145 /* Netgraph node methods */ 146 static ng_constructor_t ng_bridge_constructor; 147 static ng_rcvmsg_t ng_bridge_rcvmsg; 148 static ng_shutdown_t ng_bridge_shutdown; 149 static ng_newhook_t ng_bridge_newhook; 150 static ng_rcvdata_t ng_bridge_rcvdata; 151 static ng_disconnect_t ng_bridge_disconnect; 152 153 /* Other internal functions */ 154 static void ng_bridge_free_link(link_p link); 155 static struct ng_bridge_host *ng_bridge_get(priv_cp priv, const u_char *addr); 156 static int ng_bridge_put(priv_p priv, const u_char *addr, link_p link); 157 static void ng_bridge_rehash(priv_p priv); 158 static void ng_bridge_remove_hosts(priv_p priv, link_p link); 159 static void ng_bridge_timeout(node_p node, hook_p hook, void *arg1, int arg2); 160 static const char *ng_bridge_nodename(node_cp node); 161 162 /* Ethernet broadcast */ 163 static const u_char ng_bridge_bcast_addr[ETHER_ADDR_LEN] = 164 { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; 165 166 /* Compare Ethernet addresses using 32 and 16 bit words instead of bytewise */ 167 #define ETHER_EQUAL(a,b) (((const u_int32_t *)(a))[0] \ 168 == ((const u_int32_t *)(b))[0] \ 169 && ((const u_int16_t *)(a))[2] \ 170 == ((const u_int16_t *)(b))[2]) 171 172 /* Minimum and maximum number of hash buckets. Must be a power of two. */ 173 #define MIN_BUCKETS (1 << 5) /* 32 */ 174 #define MAX_BUCKETS (1 << 14) /* 16384 */ 175 176 /* Configuration default values */ 177 #define DEFAULT_LOOP_TIMEOUT 60 178 #define DEFAULT_MAX_STALENESS (15 * 60) /* same as ARP timeout */ 179 #define DEFAULT_MIN_STABLE_AGE 1 180 181 /****************************************************************** 182 NETGRAPH PARSE TYPES 183 ******************************************************************/ 184 185 /* 186 * How to determine the length of the table returned by NGM_BRIDGE_GET_TABLE 187 */ 188 static int 189 ng_bridge_getTableLength(const struct ng_parse_type *type, 190 const u_char *start, const u_char *buf) 191 { 192 const struct ng_bridge_host_ary *const hary 193 = (const struct ng_bridge_host_ary *)(buf - sizeof(u_int32_t)); 194 195 return hary->numHosts; 196 } 197 198 /* Parse type for struct ng_bridge_host_ary */ 199 static const struct ng_parse_struct_field ng_bridge_host_type_fields[] 200 = NG_BRIDGE_HOST_TYPE_INFO(&ng_parse_enaddr_type); 201 static const struct ng_parse_type ng_bridge_host_type = { 202 &ng_parse_struct_type, 203 &ng_bridge_host_type_fields 204 }; 205 static const struct ng_parse_array_info ng_bridge_hary_type_info = { 206 &ng_bridge_host_type, 207 ng_bridge_getTableLength 208 }; 209 static const struct ng_parse_type ng_bridge_hary_type = { 210 &ng_parse_array_type, 211 &ng_bridge_hary_type_info 212 }; 213 static const struct ng_parse_struct_field ng_bridge_host_ary_type_fields[] 214 = NG_BRIDGE_HOST_ARY_TYPE_INFO(&ng_bridge_hary_type); 215 static const struct ng_parse_type ng_bridge_host_ary_type = { 216 &ng_parse_struct_type, 217 &ng_bridge_host_ary_type_fields 218 }; 219 220 /* Parse type for struct ng_bridge_config */ 221 static const struct ng_parse_struct_field ng_bridge_config_type_fields[] 222 = NG_BRIDGE_CONFIG_TYPE_INFO; 223 static const struct ng_parse_type ng_bridge_config_type = { 224 &ng_parse_struct_type, 225 &ng_bridge_config_type_fields 226 }; 227 228 /* Parse type for struct ng_bridge_link_stat */ 229 static const struct ng_parse_struct_field ng_bridge_stats_type_fields[] 230 = NG_BRIDGE_STATS_TYPE_INFO; 231 static const struct ng_parse_type ng_bridge_stats_type = { 232 &ng_parse_struct_type, 233 &ng_bridge_stats_type_fields 234 }; 235 /* Parse type for struct ng_bridge_move_host */ 236 static const struct ng_parse_struct_field ng_bridge_move_host_type_fields[] 237 = NG_BRIDGE_MOVE_HOST_TYPE_INFO(&ng_parse_enaddr_type); 238 static const struct ng_parse_type ng_bridge_move_host_type = { 239 &ng_parse_struct_type, 240 &ng_bridge_move_host_type_fields 241 }; 242 243 /* List of commands and how to convert arguments to/from ASCII */ 244 static const struct ng_cmdlist ng_bridge_cmdlist[] = { 245 { 246 NGM_BRIDGE_COOKIE, 247 NGM_BRIDGE_SET_CONFIG, 248 "setconfig", 249 &ng_bridge_config_type, 250 NULL 251 }, 252 { 253 NGM_BRIDGE_COOKIE, 254 NGM_BRIDGE_GET_CONFIG, 255 "getconfig", 256 NULL, 257 &ng_bridge_config_type 258 }, 259 { 260 NGM_BRIDGE_COOKIE, 261 NGM_BRIDGE_RESET, 262 "reset", 263 NULL, 264 NULL 265 }, 266 { 267 NGM_BRIDGE_COOKIE, 268 NGM_BRIDGE_GET_STATS, 269 "getstats", 270 &ng_parse_uint32_type, 271 &ng_bridge_stats_type 272 }, 273 { 274 NGM_BRIDGE_COOKIE, 275 NGM_BRIDGE_CLR_STATS, 276 "clrstats", 277 &ng_parse_uint32_type, 278 NULL 279 }, 280 { 281 NGM_BRIDGE_COOKIE, 282 NGM_BRIDGE_GETCLR_STATS, 283 "getclrstats", 284 &ng_parse_uint32_type, 285 &ng_bridge_stats_type 286 }, 287 { 288 NGM_BRIDGE_COOKIE, 289 NGM_BRIDGE_GET_TABLE, 290 "gettable", 291 NULL, 292 &ng_bridge_host_ary_type 293 }, 294 { 295 NGM_BRIDGE_COOKIE, 296 NGM_BRIDGE_SET_PERSISTENT, 297 "setpersistent", 298 NULL, 299 NULL 300 }, 301 { 302 NGM_BRIDGE_COOKIE, 303 NGM_BRIDGE_MOVE_HOST, 304 "movehost", 305 &ng_bridge_move_host_type, 306 NULL 307 }, 308 { 0 } 309 }; 310 311 /* Node type descriptor */ 312 static struct ng_type ng_bridge_typestruct = { 313 .version = NG_ABI_VERSION, 314 .name = NG_BRIDGE_NODE_TYPE, 315 .constructor = ng_bridge_constructor, 316 .rcvmsg = ng_bridge_rcvmsg, 317 .shutdown = ng_bridge_shutdown, 318 .newhook = ng_bridge_newhook, 319 .rcvdata = ng_bridge_rcvdata, 320 .disconnect = ng_bridge_disconnect, 321 .cmdlist = ng_bridge_cmdlist, 322 }; 323 NETGRAPH_INIT(bridge, &ng_bridge_typestruct); 324 325 /****************************************************************** 326 NETGRAPH NODE METHODS 327 ******************************************************************/ 328 329 /* 330 * Node constructor 331 */ 332 static int 333 ng_bridge_constructor(node_p node) 334 { 335 priv_p priv; 336 337 /* Allocate and initialize private info */ 338 priv = malloc(sizeof(*priv), M_NETGRAPH_BRIDGE, M_WAITOK | M_ZERO); 339 ng_callout_init(&priv->timer); 340 341 /* Allocate and initialize hash table, etc. */ 342 priv->tab = malloc(MIN_BUCKETS * sizeof(*priv->tab), 343 M_NETGRAPH_BRIDGE, M_WAITOK | M_ZERO); 344 priv->numBuckets = MIN_BUCKETS; 345 priv->hashMask = MIN_BUCKETS - 1; 346 priv->conf.debugLevel = 1; 347 priv->conf.loopTimeout = DEFAULT_LOOP_TIMEOUT; 348 priv->conf.maxStaleness = DEFAULT_MAX_STALENESS; 349 priv->conf.minStableAge = DEFAULT_MIN_STABLE_AGE; 350 priv->sendUnknown = 1; /* classic bridge */ 351 352 NG_NODE_SET_PRIVATE(node, priv); 353 priv->node = node; 354 355 /* Start timer; timer is always running while node is alive */ 356 ng_callout(&priv->timer, node, NULL, hz, ng_bridge_timeout, NULL, 0); 357 358 /* Done */ 359 return (0); 360 } 361 362 /* 363 * Method for attaching a new hook 364 */ 365 static int 366 ng_bridge_newhook(node_p node, hook_p hook, const char *name) 367 { 368 const priv_p priv = NG_NODE_PRIVATE(node); 369 char linkName[NG_HOOKSIZ]; 370 u_int32_t linkNum; 371 link_p link; 372 const char *prefix = NG_BRIDGE_HOOK_LINK_PREFIX; 373 bool isUplink; 374 375 /* Check for a link hook */ 376 if (strlen(name) <= strlen(prefix)) 377 return (EINVAL); /* Unknown hook name */ 378 379 isUplink = (name[0] == 'u'); 380 if (isUplink) 381 prefix = NG_BRIDGE_HOOK_UPLINK_PREFIX; 382 383 /* primitive parsing */ 384 linkNum = strtoul(name + strlen(prefix), NULL, 10); 385 /* validation by comparing against the reconstucted name */ 386 snprintf(linkName, sizeof(linkName), "%s%u", prefix, linkNum); 387 if (strcmp(linkName, name) != 0) 388 return (EINVAL); 389 390 if (linkNum == 0 && isUplink) 391 return (EINVAL); 392 393 if(NG_PEER_NODE(hook) == node) 394 return (ELOOP); 395 396 link = malloc(sizeof(*link), M_NETGRAPH_BRIDGE, M_NOWAIT | M_ZERO); 397 if (link == NULL) 398 return (ENOMEM); 399 400 #define NG_BRIDGE_COUNTER_ALLOC(f) do { \ 401 link->stats.f = counter_u64_alloc(M_NOWAIT); \ 402 if (link->stats.f == NULL) \ 403 goto nomem; \ 404 } while (0) 405 NG_BRIDGE_COUNTER_ALLOC(recvOctets); 406 NG_BRIDGE_COUNTER_ALLOC(recvPackets); 407 NG_BRIDGE_COUNTER_ALLOC(recvMulticasts); 408 NG_BRIDGE_COUNTER_ALLOC(recvBroadcasts); 409 NG_BRIDGE_COUNTER_ALLOC(recvUnknown); 410 NG_BRIDGE_COUNTER_ALLOC(recvRunts); 411 NG_BRIDGE_COUNTER_ALLOC(recvInvalid); 412 NG_BRIDGE_COUNTER_ALLOC(xmitOctets); 413 NG_BRIDGE_COUNTER_ALLOC(xmitPackets); 414 NG_BRIDGE_COUNTER_ALLOC(xmitMulticasts); 415 NG_BRIDGE_COUNTER_ALLOC(xmitBroadcasts); 416 NG_BRIDGE_COUNTER_ALLOC(loopDrops); 417 NG_BRIDGE_COUNTER_ALLOC(memoryFailures); 418 #undef NG_BRIDGE_COUNTER_ALLOC 419 420 link->hook = hook; 421 if (isUplink) { 422 link->learnMac = 0; 423 link->sendUnknown = 1; 424 if (priv->numLinks == 0) /* if the first link is an uplink */ 425 priv->sendUnknown = 0; /* switch to restrictive mode */ 426 } else { 427 link->learnMac = 1; 428 link->sendUnknown = priv->sendUnknown; 429 } 430 431 NG_HOOK_SET_PRIVATE(hook, link); 432 priv->numLinks++; 433 return (0); 434 435 nomem: 436 ng_bridge_free_link(link); 437 return (ENOMEM); 438 } 439 440 /* 441 * Receive a control message 442 */ 443 static void 444 ng_bridge_clear_link_stats(struct ng_bridge_link_kernel_stats *p) 445 { 446 counter_u64_zero(p->recvOctets); 447 counter_u64_zero(p->recvPackets); 448 counter_u64_zero(p->recvMulticasts); 449 counter_u64_zero(p->recvBroadcasts); 450 counter_u64_zero(p->recvUnknown); 451 counter_u64_zero(p->recvRunts); 452 counter_u64_zero(p->recvInvalid); 453 counter_u64_zero(p->xmitOctets); 454 counter_u64_zero(p->xmitPackets); 455 counter_u64_zero(p->xmitMulticasts); 456 counter_u64_zero(p->xmitBroadcasts); 457 counter_u64_zero(p->loopDrops); 458 p->loopDetects = 0; 459 counter_u64_zero(p->memoryFailures); 460 } 461 462 static void 463 ng_bridge_free_link(link_p link) 464 { 465 counter_u64_free(link->stats.recvOctets); 466 counter_u64_free(link->stats.recvPackets); 467 counter_u64_free(link->stats.recvMulticasts); 468 counter_u64_free(link->stats.recvBroadcasts); 469 counter_u64_free(link->stats.recvUnknown); 470 counter_u64_free(link->stats.recvRunts); 471 counter_u64_free(link->stats.recvInvalid); 472 counter_u64_free(link->stats.xmitOctets); 473 counter_u64_free(link->stats.xmitPackets); 474 counter_u64_free(link->stats.xmitMulticasts); 475 counter_u64_free(link->stats.xmitBroadcasts); 476 counter_u64_free(link->stats.loopDrops); 477 counter_u64_free(link->stats.memoryFailures); 478 free(link, M_NETGRAPH_BRIDGE); 479 } 480 481 static int 482 ng_bridge_reset_link(hook_p hook, void *arg __unused) 483 { 484 link_p priv = NG_HOOK_PRIVATE(hook); 485 486 priv->loopCount = 0; 487 ng_bridge_clear_link_stats(&priv->stats); 488 return (1); 489 } 490 491 static int 492 ng_bridge_rcvmsg(node_p node, item_p item, hook_p lasthook) 493 { 494 const priv_p priv = NG_NODE_PRIVATE(node); 495 struct ng_mesg *resp = NULL; 496 int error = 0; 497 struct ng_mesg *msg; 498 499 NGI_GET_MSG(item, msg); 500 switch (msg->header.typecookie) { 501 case NGM_BRIDGE_COOKIE: 502 switch (msg->header.cmd) { 503 case NGM_BRIDGE_GET_CONFIG: 504 { 505 struct ng_bridge_config *conf; 506 507 NG_MKRESPONSE(resp, msg, 508 sizeof(struct ng_bridge_config), M_NOWAIT); 509 if (resp == NULL) { 510 error = ENOMEM; 511 break; 512 } 513 conf = (struct ng_bridge_config *)resp->data; 514 *conf = priv->conf; /* no sanity checking needed */ 515 break; 516 } 517 case NGM_BRIDGE_SET_CONFIG: 518 { 519 struct ng_bridge_config *conf; 520 521 if (msg->header.arglen 522 != sizeof(struct ng_bridge_config)) { 523 error = EINVAL; 524 break; 525 } 526 conf = (struct ng_bridge_config *)msg->data; 527 priv->conf = *conf; 528 break; 529 } 530 case NGM_BRIDGE_RESET: 531 { 532 /* Flush all entries in the hash table */ 533 ng_bridge_remove_hosts(priv, NULL); 534 535 /* Reset all loop detection counters and stats */ 536 NG_NODE_FOREACH_HOOK(node, ng_bridge_reset_link, NULL); 537 break; 538 } 539 case NGM_BRIDGE_GET_STATS: 540 case NGM_BRIDGE_CLR_STATS: 541 case NGM_BRIDGE_GETCLR_STATS: 542 { 543 hook_p hook; 544 link_p link; 545 char linkName[NG_HOOKSIZ]; 546 int linkNum; 547 548 /* Get link number */ 549 if (msg->header.arglen != sizeof(u_int32_t)) { 550 error = EINVAL; 551 break; 552 } 553 linkNum = *((int32_t *)msg->data); 554 if (linkNum < 0) 555 snprintf(linkName, sizeof(linkName), 556 "%s%u", NG_BRIDGE_HOOK_UPLINK_PREFIX, -linkNum); 557 else 558 snprintf(linkName, sizeof(linkName), 559 "%s%u", NG_BRIDGE_HOOK_LINK_PREFIX, linkNum); 560 561 if ((hook = ng_findhook(node, linkName)) == NULL) { 562 error = ENOTCONN; 563 break; 564 } 565 link = NG_HOOK_PRIVATE(hook); 566 567 /* Get/clear stats */ 568 if (msg->header.cmd != NGM_BRIDGE_CLR_STATS) { 569 struct ng_bridge_link_stats *rs; 570 571 NG_MKRESPONSE(resp, msg, 572 sizeof(link->stats), M_NOWAIT); 573 if (resp == NULL) { 574 error = ENOMEM; 575 break; 576 } 577 rs = (struct ng_bridge_link_stats *)resp->data; 578 #define FETCH(x) rs->x = counter_u64_fetch(link->stats.x) 579 FETCH(recvOctets); 580 FETCH(recvPackets); 581 FETCH(recvMulticasts); 582 FETCH(recvBroadcasts); 583 FETCH(recvUnknown); 584 FETCH(recvRunts); 585 FETCH(recvInvalid); 586 FETCH(xmitOctets); 587 FETCH(xmitPackets); 588 FETCH(xmitMulticasts); 589 FETCH(xmitBroadcasts); 590 FETCH(loopDrops); 591 rs->loopDetects = link->stats.loopDetects; 592 FETCH(memoryFailures); 593 #undef FETCH 594 } 595 if (msg->header.cmd != NGM_BRIDGE_GET_STATS) 596 ng_bridge_clear_link_stats(&link->stats); 597 break; 598 } 599 case NGM_BRIDGE_GET_TABLE: 600 { 601 struct ng_bridge_host_ary *ary; 602 struct ng_bridge_host *host; 603 int i = 0, bucket; 604 605 NG_MKRESPONSE(resp, msg, sizeof(*ary) 606 + (priv->numHosts * sizeof(*ary->hosts)), M_NOWAIT); 607 if (resp == NULL) { 608 error = ENOMEM; 609 break; 610 } 611 ary = (struct ng_bridge_host_ary *)resp->data; 612 ary->numHosts = priv->numHosts; 613 for (bucket = 0; bucket < priv->numBuckets; bucket++) { 614 SLIST_FOREACH(host, &priv->tab[bucket], next) { 615 memcpy(ary->hosts[i].addr, 616 host->addr, 617 sizeof(ary->hosts[i].addr)); 618 ary->hosts[i].age = host->age; 619 ary->hosts[i].staleness = host->staleness; 620 strncpy(ary->hosts[i].hook, 621 NG_HOOK_NAME(host->link->hook), 622 sizeof(ary->hosts[i].hook)); 623 i++; 624 } 625 } 626 break; 627 } 628 case NGM_BRIDGE_SET_PERSISTENT: 629 { 630 priv->persistent = 1; 631 break; 632 } 633 case NGM_BRIDGE_MOVE_HOST: 634 { 635 struct ng_bridge_move_host *mh; 636 hook_p hook; 637 638 if (msg->header.arglen < sizeof(*mh)) { 639 error = EINVAL; 640 break; 641 } 642 mh = (struct ng_bridge_move_host *)msg->data; 643 hook = (mh->hook[0] == 0) 644 ? lasthook 645 : ng_findhook(node, mh->hook); 646 if (hook == NULL) { 647 error = ENOENT; 648 break; 649 } 650 error = ng_bridge_put(priv, mh->addr, NG_HOOK_PRIVATE(hook)); 651 break; 652 } 653 default: 654 error = EINVAL; 655 break; 656 } 657 break; 658 default: 659 error = EINVAL; 660 break; 661 } 662 663 /* Done */ 664 NG_RESPOND_MSG(error, node, item, resp); 665 NG_FREE_MSG(msg); 666 return (error); 667 } 668 669 /* 670 * Receive data on a hook 671 */ 672 struct ng_bridge_send_ctx { 673 link_p foundFirst, incoming; 674 struct mbuf * m; 675 int manycast, error; 676 }; 677 678 /* 679 * Update stats and send out 680 */ 681 static inline int 682 ng_bridge_send_data(link_cp dst, int manycast, struct mbuf *m, item_p item) { 683 int error = 0; 684 size_t len = m->m_pkthdr.len; 685 686 if(item != NULL) 687 NG_FWD_NEW_DATA(error, item, dst->hook, m); 688 else 689 NG_SEND_DATA_ONLY(error, dst->hook, m); 690 691 if (error) { 692 if (error == ENOMEM) 693 counter_u64_add(dst->stats.memoryFailures, 1); 694 /* The packet is still ours */ 695 if (item != NULL) 696 NG_FREE_ITEM(item); 697 if (m != NULL) 698 NG_FREE_M(m); 699 return (error); 700 } 701 702 counter_u64_add(dst->stats.xmitPackets, 1); 703 counter_u64_add(dst->stats.xmitOctets, len); 704 switch (manycast) { 705 default: /* unknown unicast */ 706 break; 707 case 1: /* multicast */ 708 counter_u64_add(dst->stats.xmitMulticasts, 1); 709 break; 710 case 2: /* broadcast */ 711 counter_u64_add(dst->stats.xmitBroadcasts, 1); 712 break; 713 } 714 return (0); 715 } 716 717 /* 718 * Loop body for sending to multiple destinations 719 * return 0 to stop looping 720 */ 721 static int 722 ng_bridge_send_ctx(hook_p dst, void *arg) 723 { 724 struct ng_bridge_send_ctx *ctx = arg; 725 link_p destLink = NG_HOOK_PRIVATE(dst); 726 struct mbuf *m2 = NULL; 727 int error = 0; 728 729 /* Skip incoming link */ 730 if (destLink == ctx->incoming) { 731 return (1); 732 } 733 734 /* Skip sending unknowns to undesired links */ 735 if (!ctx->manycast && !destLink->sendUnknown) 736 return (1); 737 738 if (ctx->foundFirst == NULL) { 739 /* 740 * This is the first usable link we have found. 741 * Reserve it for the originals. 742 * If we never find another we save a copy. 743 */ 744 ctx->foundFirst = destLink; 745 return (1); 746 } 747 748 /* 749 * It's usable link but not the reserved (first) one. 750 * Copy mbuf info for sending. 751 */ 752 m2 = m_dup(ctx->m, M_NOWAIT); 753 if (m2 == NULL) { 754 counter_u64_add(ctx->incoming->stats.memoryFailures, 1); 755 ctx->error = ENOBUFS; 756 return (0); /* abort loop, do not try again and again */ 757 } 758 759 /* Send packet */ 760 error = ng_bridge_send_data(destLink, ctx->manycast, m2, NULL); 761 if (error) 762 ctx->error = error; 763 return (1); 764 } 765 766 static int 767 ng_bridge_rcvdata(hook_p hook, item_p item) 768 { 769 const node_p node = NG_HOOK_NODE(hook); 770 const priv_p priv = NG_NODE_PRIVATE(node); 771 struct ng_bridge_host *host; 772 struct ether_header *eh; 773 struct ng_bridge_send_ctx ctx = { 0 }; 774 775 NGI_GET_M(item, ctx.m); 776 777 ctx.incoming = NG_HOOK_PRIVATE(hook); 778 /* Sanity check packet and pull up header */ 779 if (ctx.m->m_pkthdr.len < ETHER_HDR_LEN) { 780 counter_u64_add(ctx.incoming->stats.recvRunts, 1); 781 NG_FREE_ITEM(item); 782 NG_FREE_M(ctx.m); 783 return (EINVAL); 784 } 785 if (ctx.m->m_len < ETHER_HDR_LEN && !(ctx.m = m_pullup(ctx.m, ETHER_HDR_LEN))) { 786 counter_u64_add(ctx.incoming->stats.memoryFailures, 1); 787 NG_FREE_ITEM(item); 788 return (ENOBUFS); 789 } 790 eh = mtod(ctx.m, struct ether_header *); 791 if ((eh->ether_shost[0] & 1) != 0) { 792 counter_u64_add(ctx.incoming->stats.recvInvalid, 1); 793 NG_FREE_ITEM(item); 794 NG_FREE_M(ctx.m); 795 return (EINVAL); 796 } 797 798 /* Is link disabled due to a loopback condition? */ 799 if (ctx.incoming->loopCount != 0) { 800 counter_u64_add(ctx.incoming->stats.loopDrops, 1); 801 NG_FREE_ITEM(item); 802 NG_FREE_M(ctx.m); 803 return (ELOOP); 804 } 805 806 /* Update stats */ 807 counter_u64_add(ctx.incoming->stats.recvPackets, 1); 808 counter_u64_add(ctx.incoming->stats.recvOctets, ctx.m->m_pkthdr.len); 809 if ((ctx.manycast = (eh->ether_dhost[0] & 1)) != 0) { 810 if (ETHER_EQUAL(eh->ether_dhost, ng_bridge_bcast_addr)) { 811 counter_u64_add(ctx.incoming->stats.recvBroadcasts, 1); 812 ctx.manycast = 2; 813 } else 814 counter_u64_add(ctx.incoming->stats.recvMulticasts, 1); 815 } 816 817 /* Look up packet's source Ethernet address in hashtable */ 818 if ((host = ng_bridge_get(priv, eh->ether_shost)) != NULL) 819 /* Update time since last heard from this host. 820 * This is safe without locking, because it's 821 * the only operation during shared access. 822 */ 823 if (__predict_false(host->staleness > 0)) 824 host->staleness = 0; 825 826 if ((host == NULL && ctx.incoming->learnMac) || 827 (host != NULL && host->link != ctx.incoming)) { 828 struct ng_mesg *msg; 829 struct ng_bridge_move_host *mh; 830 int error = 0; 831 832 NG_MKMESSAGE(msg, NGM_BRIDGE_COOKIE, NGM_BRIDGE_MOVE_HOST, 833 sizeof(*mh), M_NOWAIT); 834 if (msg == NULL) { 835 counter_u64_add(ctx.incoming->stats.memoryFailures, 1); 836 NG_FREE_ITEM(item); 837 NG_FREE_M(ctx.m); 838 return (ENOMEM); 839 } 840 mh = (struct ng_bridge_move_host *)msg->data; 841 strncpy(mh->hook, NG_HOOK_NAME(ctx.incoming->hook), 842 sizeof(mh->hook)); 843 memcpy(mh->addr, eh->ether_shost, sizeof(mh->addr)); 844 NG_SEND_MSG_ID(error, node, msg, NG_NODE_ID(node), 845 NG_NODE_ID(node)); 846 if (error) 847 counter_u64_add(ctx.incoming->stats.memoryFailures, 1); 848 } 849 850 if (host != NULL && host->link != ctx.incoming) { 851 if (host->age < priv->conf.minStableAge) { 852 /* Drop packet on instable links */ 853 counter_u64_add(ctx.incoming->stats.loopDrops, 1); 854 NG_FREE_ITEM(item); 855 NG_FREE_M(ctx.m); 856 return (ELOOP); 857 } 858 } 859 860 /* 861 * If unicast and destination host known, deliver to host's link, 862 * unless it is the same link as the packet came in on. 863 */ 864 if (!ctx.manycast) { 865 /* Determine packet destination link */ 866 if ((host = ng_bridge_get(priv, eh->ether_dhost)) != NULL) { 867 link_p destLink = host->link; 868 869 /* If destination same as incoming link, do nothing */ 870 if (destLink == ctx.incoming) { 871 NG_FREE_ITEM(item); 872 NG_FREE_M(ctx.m); 873 return (0); 874 } 875 876 /* Deliver packet out the destination link */ 877 return (ng_bridge_send_data(destLink, ctx.manycast, ctx.m, item)); 878 } 879 880 /* Destination host is not known */ 881 counter_u64_add(ctx.incoming->stats.recvUnknown, 1); 882 } 883 884 /* Distribute unknown, multicast, broadcast pkts to all other links */ 885 NG_NODE_FOREACH_HOOK(node, ng_bridge_send_ctx, &ctx); 886 887 /* Finally send out on the first link found */ 888 if (ctx.foundFirst != NULL) { 889 int error = ng_bridge_send_data(ctx.foundFirst, ctx.manycast, ctx.m, item); 890 if (error) 891 ctx.error = error; 892 } else { /* nothing to send at all */ 893 NG_FREE_ITEM(item); 894 NG_FREE_M(ctx.m); 895 } 896 897 return (ctx.error); 898 } 899 900 /* 901 * Shutdown node 902 */ 903 static int 904 ng_bridge_shutdown(node_p node) 905 { 906 const priv_p priv = NG_NODE_PRIVATE(node); 907 908 /* 909 * Shut down everything including the timer. Even if the 910 * callout has already been dequeued and is about to be 911 * run, ng_bridge_timeout() won't be fired as the node 912 * is already marked NGF_INVALID, so we're safe to free 913 * the node now. 914 */ 915 KASSERT(priv->numLinks == 0 && priv->numHosts == 0, 916 ("%s: numLinks=%d numHosts=%d", 917 __func__, priv->numLinks, priv->numHosts)); 918 ng_uncallout(&priv->timer, node); 919 NG_NODE_SET_PRIVATE(node, NULL); 920 NG_NODE_UNREF(node); 921 free(priv->tab, M_NETGRAPH_BRIDGE); 922 free(priv, M_NETGRAPH_BRIDGE); 923 return (0); 924 } 925 926 /* 927 * Hook disconnection. 928 */ 929 static int 930 ng_bridge_disconnect(hook_p hook) 931 { 932 const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook)); 933 link_p link = NG_HOOK_PRIVATE(hook); 934 935 /* Remove all hosts associated with this link */ 936 ng_bridge_remove_hosts(priv, link); 937 938 /* Free associated link information */ 939 ng_bridge_free_link(link); 940 priv->numLinks--; 941 942 /* If no more hooks, go away */ 943 if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0) 944 && (NG_NODE_IS_VALID(NG_HOOK_NODE(hook))) 945 && !priv->persistent) { 946 ng_rmnode_self(NG_HOOK_NODE(hook)); 947 } 948 return (0); 949 } 950 951 /****************************************************************** 952 HASH TABLE FUNCTIONS 953 ******************************************************************/ 954 955 /* 956 * Hash algorithm 957 */ 958 #define HASH(addr,mask) ( (((const u_int16_t *)(addr))[0] \ 959 ^ ((const u_int16_t *)(addr))[1] \ 960 ^ ((const u_int16_t *)(addr))[2]) & (mask) ) 961 962 /* 963 * Find a host entry in the table. 964 */ 965 static struct ng_bridge_host * 966 ng_bridge_get(priv_cp priv, const u_char *addr) 967 { 968 const int bucket = HASH(addr, priv->hashMask); 969 struct ng_bridge_host *host; 970 971 SLIST_FOREACH(host, &priv->tab[bucket], next) { 972 if (ETHER_EQUAL(host->addr, addr)) 973 return (host); 974 } 975 return (NULL); 976 } 977 978 /* 979 * Add a host entry to the table. If it already exists, move it 980 * to the new link. Returns 0 on success. 981 */ 982 static int 983 ng_bridge_put(priv_p priv, const u_char *addr, link_p link) 984 { 985 const int bucket = HASH(addr, priv->hashMask); 986 struct ng_bridge_host *host; 987 988 if ((host = ng_bridge_get(priv, addr)) != NULL) { 989 /* Host already on the correct link? */ 990 if (host->link == link) 991 return 0; 992 993 /* Move old host over to new link */ 994 if (host->age >= priv->conf.minStableAge) { 995 host->link = link; 996 host->age = 0; 997 return (0); 998 } 999 /* 1000 * If the host was recently moved to the old link and 1001 * it's now jumping to a new link, declare a loopback 1002 * condition. 1003 */ 1004 if (priv->conf.debugLevel >= 2) 1005 log(LOG_WARNING, "ng_bridge: %s:" 1006 " loopback detected on %s\n", 1007 ng_bridge_nodename(priv->node), 1008 NG_HOOK_NAME(link->hook)); 1009 1010 /* Mark link as linka non grata */ 1011 link->loopCount = priv->conf.loopTimeout; 1012 link->stats.loopDetects++; 1013 1014 /* Forget all hosts on this link */ 1015 ng_bridge_remove_hosts(priv, link); 1016 return (ELOOP); 1017 } 1018 1019 /* Allocate and initialize new hashtable entry */ 1020 host = malloc(sizeof(*host), M_NETGRAPH_BRIDGE, M_NOWAIT); 1021 if (host == NULL) 1022 return (ENOMEM); 1023 bcopy(addr, host->addr, ETHER_ADDR_LEN); 1024 host->link = link; 1025 host->staleness = 0; 1026 host->age = 0; 1027 1028 /* Add new element to hash bucket */ 1029 SLIST_INSERT_HEAD(&priv->tab[bucket], host, next); 1030 priv->numHosts++; 1031 1032 /* Resize table if necessary */ 1033 ng_bridge_rehash(priv); 1034 return (0); 1035 } 1036 1037 /* 1038 * Resize the hash table. We try to maintain the number of buckets 1039 * such that the load factor is in the range 0.25 to 1.0. 1040 * 1041 * If we can't get the new memory then we silently fail. This is OK 1042 * because things will still work and we'll try again soon anyway. 1043 */ 1044 static void 1045 ng_bridge_rehash(priv_p priv) 1046 { 1047 struct ng_bridge_bucket *newTab; 1048 int oldBucket, newBucket; 1049 int newNumBuckets; 1050 u_int newMask; 1051 1052 /* Is table too full or too empty? */ 1053 if (priv->numHosts > priv->numBuckets 1054 && (priv->numBuckets << 1) <= MAX_BUCKETS) 1055 newNumBuckets = priv->numBuckets << 1; 1056 else if (priv->numHosts < (priv->numBuckets >> 2) 1057 && (priv->numBuckets >> 2) >= MIN_BUCKETS) 1058 newNumBuckets = priv->numBuckets >> 2; 1059 else 1060 return; 1061 newMask = newNumBuckets - 1; 1062 1063 /* Allocate and initialize new table */ 1064 newTab = malloc(newNumBuckets * sizeof(*newTab), 1065 M_NETGRAPH_BRIDGE, M_NOWAIT | M_ZERO); 1066 if (newTab == NULL) 1067 return; 1068 1069 /* Move all entries from old table to new table */ 1070 for (oldBucket = 0; oldBucket < priv->numBuckets; oldBucket++) { 1071 struct ng_bridge_bucket *const oldList = &priv->tab[oldBucket]; 1072 1073 while (!SLIST_EMPTY(oldList)) { 1074 struct ng_bridge_host *const host 1075 = SLIST_FIRST(oldList); 1076 1077 SLIST_REMOVE_HEAD(oldList, next); 1078 newBucket = HASH(host->addr, newMask); 1079 SLIST_INSERT_HEAD(&newTab[newBucket], host, next); 1080 } 1081 } 1082 1083 /* Replace old table with new one */ 1084 if (priv->conf.debugLevel >= 3) { 1085 log(LOG_INFO, "ng_bridge: %s: table size %d -> %d\n", 1086 ng_bridge_nodename(priv->node), 1087 priv->numBuckets, newNumBuckets); 1088 } 1089 free(priv->tab, M_NETGRAPH_BRIDGE); 1090 priv->numBuckets = newNumBuckets; 1091 priv->hashMask = newMask; 1092 priv->tab = newTab; 1093 return; 1094 } 1095 1096 /****************************************************************** 1097 MISC FUNCTIONS 1098 ******************************************************************/ 1099 1100 /* 1101 * Remove all hosts associated with a specific link from the hashtable. 1102 * If linkNum == -1, then remove all hosts in the table. 1103 */ 1104 static void 1105 ng_bridge_remove_hosts(priv_p priv, link_p link) 1106 { 1107 int bucket; 1108 1109 for (bucket = 0; bucket < priv->numBuckets; bucket++) { 1110 struct ng_bridge_host **hptr = &SLIST_FIRST(&priv->tab[bucket]); 1111 1112 while (*hptr != NULL) { 1113 struct ng_bridge_host *const host = *hptr; 1114 1115 if (link == NULL || host->link == link) { 1116 *hptr = SLIST_NEXT(host, next); 1117 free(host, M_NETGRAPH_BRIDGE); 1118 priv->numHosts--; 1119 } else 1120 hptr = &SLIST_NEXT(host, next); 1121 } 1122 } 1123 } 1124 1125 /* 1126 * Handle our once-per-second timeout event. We do two things: 1127 * we decrement link->loopCount for those links being muted due to 1128 * a detected loopback condition, and we remove any hosts from 1129 * the hashtable whom we haven't heard from in a long while. 1130 */ 1131 static int 1132 ng_bridge_unmute(hook_p hook, void *arg) 1133 { 1134 link_p link = NG_HOOK_PRIVATE(hook); 1135 node_p node = NG_HOOK_NODE(hook); 1136 priv_p priv = NG_NODE_PRIVATE(node); 1137 int *counter = arg; 1138 1139 if (link->loopCount != 0) { 1140 link->loopCount--; 1141 if (link->loopCount == 0 && priv->conf.debugLevel >= 2) { 1142 log(LOG_INFO, "ng_bridge: %s:" 1143 " restoring looped back %s\n", 1144 ng_bridge_nodename(node), NG_HOOK_NAME(hook)); 1145 } 1146 } 1147 (*counter)++; 1148 return (1); 1149 } 1150 1151 static void 1152 ng_bridge_timeout(node_p node, hook_p hook, void *arg1, int arg2) 1153 { 1154 const priv_p priv = NG_NODE_PRIVATE(node); 1155 int bucket; 1156 int counter = 0; 1157 1158 /* Update host time counters and remove stale entries */ 1159 for (bucket = 0; bucket < priv->numBuckets; bucket++) { 1160 struct ng_bridge_host **hptr = &SLIST_FIRST(&priv->tab[bucket]); 1161 1162 while (*hptr != NULL) { 1163 struct ng_bridge_host *const host = *hptr; 1164 1165 /* Remove hosts we haven't heard from in a while */ 1166 if (++host->staleness >= priv->conf.maxStaleness) { 1167 *hptr = SLIST_NEXT(host, next); 1168 free(host, M_NETGRAPH_BRIDGE); 1169 priv->numHosts--; 1170 } else { 1171 if (host->age < 0xffff) 1172 host->age++; 1173 hptr = &SLIST_NEXT(host, next); 1174 counter++; 1175 } 1176 } 1177 } 1178 KASSERT(priv->numHosts == counter, 1179 ("%s: hosts: %d != %d", __func__, priv->numHosts, counter)); 1180 1181 /* Decrease table size if necessary */ 1182 ng_bridge_rehash(priv); 1183 1184 /* Decrease loop counter on muted looped back links */ 1185 counter = 0; 1186 NG_NODE_FOREACH_HOOK(node, ng_bridge_unmute, &counter); 1187 KASSERT(priv->numLinks == counter, 1188 ("%s: links: %d != %d", __func__, priv->numLinks, counter)); 1189 1190 /* Register a new timeout, keeping the existing node reference */ 1191 ng_callout(&priv->timer, node, NULL, hz, ng_bridge_timeout, NULL, 0); 1192 } 1193 1194 /* 1195 * Return node's "name", even if it doesn't have one. 1196 */ 1197 static const char * 1198 ng_bridge_nodename(node_cp node) 1199 { 1200 static char name[NG_NODESIZ]; 1201 1202 if (NG_NODE_HAS_NAME(node)) 1203 snprintf(name, sizeof(name), "%s", NG_NODE_NAME(node)); 1204 else 1205 snprintf(name, sizeof(name), "[%x]", ng_node2ID(node)); 1206 return name; 1207 } 1208