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 struct unrhdr *linkUnit; /* link unit number allocator */
128 struct unrhdr *uplinkUnit; /* uplink unit number allocator */
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 /* [up]link prefix matching */
146 struct ng_link_prefix {
147 const char * const prefix;
148 size_t len;
149 };
150
151 static const struct ng_link_prefix link_pfx = {
152 .prefix = NG_BRIDGE_HOOK_LINK_PREFIX,
153 .len = sizeof(NG_BRIDGE_HOOK_LINK_PREFIX) - 1,
154 };
155 static const struct ng_link_prefix uplink_pfx = {
156 .prefix = NG_BRIDGE_HOOK_UPLINK_PREFIX,
157 .len = sizeof(NG_BRIDGE_HOOK_UPLINK_PREFIX) - 1,
158 };
159
160 /* Netgraph node methods */
161 static ng_constructor_t ng_bridge_constructor;
162 static ng_rcvmsg_t ng_bridge_rcvmsg;
163 static ng_shutdown_t ng_bridge_shutdown;
164 static ng_newhook_t ng_bridge_newhook;
165 static ng_rcvdata_t ng_bridge_rcvdata;
166 static ng_disconnect_t ng_bridge_disconnect;
167
168 /* Other internal functions */
169 static const struct ng_link_prefix *ng_get_link_prefix(const char *name);
170 static void ng_bridge_free_link(link_p link);
171 static struct ng_bridge_host *ng_bridge_get(priv_cp priv, const u_char *addr);
172 static int ng_bridge_put(priv_p priv, const u_char *addr, link_p link);
173 static void ng_bridge_rehash(priv_p priv);
174 static void ng_bridge_remove_hosts(priv_p priv, link_p link);
175 static void ng_bridge_timeout(node_p node, hook_p hook, void *arg1, int arg2);
176 static const char *ng_bridge_nodename(node_cp node);
177
178 /* Ethernet broadcast */
179 static const u_char ng_bridge_bcast_addr[ETHER_ADDR_LEN] =
180 { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
181
182 /* Compare Ethernet addresses using 32 and 16 bit words instead of bytewise */
183 #define ETHER_EQUAL(a,b) (((const u_int32_t *)(a))[0] \
184 == ((const u_int32_t *)(b))[0] \
185 && ((const u_int16_t *)(a))[2] \
186 == ((const u_int16_t *)(b))[2])
187
188 /* Minimum and maximum number of hash buckets. Must be a power of two. */
189 #define MIN_BUCKETS (1 << 5) /* 32 */
190 #define MAX_BUCKETS (1 << 14) /* 16384 */
191
192 /* Configuration default values */
193 #define DEFAULT_LOOP_TIMEOUT 60
194 #define DEFAULT_MAX_STALENESS (15 * 60) /* same as ARP timeout */
195 #define DEFAULT_MIN_STABLE_AGE 1
196
197 /******************************************************************
198 NETGRAPH PARSE TYPES
199 ******************************************************************/
200
201 /*
202 * How to determine the length of the table returned by NGM_BRIDGE_GET_TABLE
203 */
204 static int
ng_bridge_getTableLength(const struct ng_parse_type * type,const u_char * start,const u_char * buf)205 ng_bridge_getTableLength(const struct ng_parse_type *type,
206 const u_char *start, const u_char *buf)
207 {
208 const struct ng_bridge_host_ary *const hary
209 = (const struct ng_bridge_host_ary *)(buf - sizeof(u_int32_t));
210
211 return hary->numHosts;
212 }
213
214 /* Parse type for struct ng_bridge_host_ary */
215 static const struct ng_parse_struct_field ng_bridge_host_type_fields[]
216 = NG_BRIDGE_HOST_TYPE_INFO(&ng_parse_enaddr_type);
217 static const struct ng_parse_type ng_bridge_host_type = {
218 &ng_parse_struct_type,
219 &ng_bridge_host_type_fields
220 };
221 static const struct ng_parse_array_info ng_bridge_hary_type_info = {
222 &ng_bridge_host_type,
223 ng_bridge_getTableLength
224 };
225 static const struct ng_parse_type ng_bridge_hary_type = {
226 &ng_parse_array_type,
227 &ng_bridge_hary_type_info
228 };
229 static const struct ng_parse_struct_field ng_bridge_host_ary_type_fields[]
230 = NG_BRIDGE_HOST_ARY_TYPE_INFO(&ng_bridge_hary_type);
231 static const struct ng_parse_type ng_bridge_host_ary_type = {
232 &ng_parse_struct_type,
233 &ng_bridge_host_ary_type_fields
234 };
235
236 /* Parse type for struct ng_bridge_config */
237 static const struct ng_parse_struct_field ng_bridge_config_type_fields[]
238 = NG_BRIDGE_CONFIG_TYPE_INFO;
239 static const struct ng_parse_type ng_bridge_config_type = {
240 &ng_parse_struct_type,
241 &ng_bridge_config_type_fields
242 };
243
244 /* Parse type for struct ng_bridge_link_stat */
245 static const struct ng_parse_struct_field ng_bridge_stats_type_fields[]
246 = NG_BRIDGE_STATS_TYPE_INFO;
247 static const struct ng_parse_type ng_bridge_stats_type = {
248 &ng_parse_struct_type,
249 &ng_bridge_stats_type_fields
250 };
251 /* Parse type for struct ng_bridge_move_host */
252 static const struct ng_parse_struct_field ng_bridge_move_host_type_fields[]
253 = NG_BRIDGE_MOVE_HOST_TYPE_INFO(&ng_parse_enaddr_type);
254 static const struct ng_parse_type ng_bridge_move_host_type = {
255 &ng_parse_struct_type,
256 &ng_bridge_move_host_type_fields
257 };
258
259 /* List of commands and how to convert arguments to/from ASCII */
260 static const struct ng_cmdlist ng_bridge_cmdlist[] = {
261 {
262 NGM_BRIDGE_COOKIE,
263 NGM_BRIDGE_SET_CONFIG,
264 "setconfig",
265 &ng_bridge_config_type,
266 NULL
267 },
268 {
269 NGM_BRIDGE_COOKIE,
270 NGM_BRIDGE_GET_CONFIG,
271 "getconfig",
272 NULL,
273 &ng_bridge_config_type
274 },
275 {
276 NGM_BRIDGE_COOKIE,
277 NGM_BRIDGE_RESET,
278 "reset",
279 NULL,
280 NULL
281 },
282 {
283 NGM_BRIDGE_COOKIE,
284 NGM_BRIDGE_GET_STATS,
285 "getstats",
286 &ng_parse_uint32_type,
287 &ng_bridge_stats_type
288 },
289 {
290 NGM_BRIDGE_COOKIE,
291 NGM_BRIDGE_CLR_STATS,
292 "clrstats",
293 &ng_parse_uint32_type,
294 NULL
295 },
296 {
297 NGM_BRIDGE_COOKIE,
298 NGM_BRIDGE_GETCLR_STATS,
299 "getclrstats",
300 &ng_parse_uint32_type,
301 &ng_bridge_stats_type
302 },
303 {
304 NGM_BRIDGE_COOKIE,
305 NGM_BRIDGE_GET_TABLE,
306 "gettable",
307 NULL,
308 &ng_bridge_host_ary_type
309 },
310 {
311 NGM_BRIDGE_COOKIE,
312 NGM_BRIDGE_SET_PERSISTENT,
313 "setpersistent",
314 NULL,
315 NULL
316 },
317 {
318 NGM_BRIDGE_COOKIE,
319 NGM_BRIDGE_MOVE_HOST,
320 "movehost",
321 &ng_bridge_move_host_type,
322 NULL
323 },
324 { 0 }
325 };
326
327 /* Node type descriptor */
328 static struct ng_type ng_bridge_typestruct = {
329 .version = NG_ABI_VERSION,
330 .name = NG_BRIDGE_NODE_TYPE,
331 .constructor = ng_bridge_constructor,
332 .rcvmsg = ng_bridge_rcvmsg,
333 .shutdown = ng_bridge_shutdown,
334 .newhook = ng_bridge_newhook,
335 .rcvdata = ng_bridge_rcvdata,
336 .disconnect = ng_bridge_disconnect,
337 .cmdlist = ng_bridge_cmdlist,
338 };
339 NETGRAPH_INIT(bridge, &ng_bridge_typestruct);
340
341 /******************************************************************
342 NETGRAPH NODE METHODS
343 ******************************************************************/
344
345 /*
346 * Node constructor
347 */
348 static int
ng_bridge_constructor(node_p node)349 ng_bridge_constructor(node_p node)
350 {
351 priv_p priv;
352
353 /* Allocate and initialize private info */
354 priv = malloc(sizeof(*priv), M_NETGRAPH_BRIDGE, M_WAITOK | M_ZERO);
355 ng_callout_init(&priv->timer);
356
357 /* Allocate and initialize hash table, etc. */
358 priv->tab = malloc(MIN_BUCKETS * sizeof(*priv->tab),
359 M_NETGRAPH_BRIDGE, M_WAITOK | M_ZERO);
360 priv->numBuckets = MIN_BUCKETS;
361 priv->hashMask = MIN_BUCKETS - 1;
362 priv->conf.debugLevel = 1;
363 priv->conf.loopTimeout = DEFAULT_LOOP_TIMEOUT;
364 priv->conf.maxStaleness = DEFAULT_MAX_STALENESS;
365 priv->conf.minStableAge = DEFAULT_MIN_STABLE_AGE;
366 priv->sendUnknown = 1; /* classic bridge */
367
368 NG_NODE_SET_PRIVATE(node, priv);
369 priv->node = node;
370
371 /* Allocators for links. Historically "uplink0" is not allowed. */
372 priv->linkUnit = new_unrhdr(0, INT_MAX, NULL);
373 priv->uplinkUnit = new_unrhdr(1, INT_MAX, NULL);
374
375 /* Start timer; timer is always running while node is alive */
376 ng_callout(&priv->timer, node, NULL, hz, ng_bridge_timeout, NULL, 0);
377
378 /* Done */
379 return (0);
380 }
381
382 /*
383 * Method for attaching a new hook
384 */
385 static int
ng_bridge_newhook(node_p node,hook_p hook,const char * name)386 ng_bridge_newhook(node_p node, hook_p hook, const char *name)
387 {
388 const priv_p priv = NG_NODE_PRIVATE(node);
389 link_p link;
390 bool isUplink;
391 uint32_t linkNum;
392 struct unrhdr *unit;
393
394 const struct ng_link_prefix *pfx = ng_get_link_prefix(name);
395 if (pfx == NULL)
396 return (EINVAL); /* not a valid prefix */
397
398 isUplink = (pfx == &uplink_pfx);
399 unit = isUplink ? priv->uplinkUnit : priv->linkUnit;
400
401 if (strlen(name) > pfx->len) { /* given number */
402 char linkName[NG_HOOKSIZ];
403 int rvnum __diagused;
404
405 linkNum = strtoul(name + pfx->len, NULL, 10);
406 /* Validate by comparing against the reconstucted name. */
407 snprintf(linkName, sizeof(linkName), "%s%u", pfx->prefix,
408 linkNum);
409 if (strcmp(linkName, name) != 0)
410 return (EINVAL);
411 if (linkNum == 0 && isUplink)
412 return (EINVAL);
413 rvnum = alloc_unr_specific(unit, linkNum);
414 MPASS(rvnum == linkNum);
415 } else {
416 /* auto-assign and update hook name */
417 linkNum = alloc_unr(unit);
418 MPASS(linkNum != -1);
419 snprintf(NG_HOOK_NAME(hook), NG_HOOKSIZ, "%s%u", pfx->prefix,
420 linkNum);
421 }
422
423 if (NG_PEER_NODE(hook) == node) {
424 free_unr(unit, linkNum);
425 return (ELOOP);
426 }
427
428 link = malloc(sizeof(*link), M_NETGRAPH_BRIDGE, M_NOWAIT | M_ZERO);
429 if (link == NULL) {
430 free_unr(unit, linkNum);
431 return (ENOMEM);
432 }
433
434 #define NG_BRIDGE_COUNTER_ALLOC(f) do { \
435 link->stats.f = counter_u64_alloc(M_NOWAIT); \
436 if (link->stats.f == NULL) \
437 goto nomem; \
438 } while (0)
439 NG_BRIDGE_COUNTER_ALLOC(recvOctets);
440 NG_BRIDGE_COUNTER_ALLOC(recvPackets);
441 NG_BRIDGE_COUNTER_ALLOC(recvMulticasts);
442 NG_BRIDGE_COUNTER_ALLOC(recvBroadcasts);
443 NG_BRIDGE_COUNTER_ALLOC(recvUnknown);
444 NG_BRIDGE_COUNTER_ALLOC(recvRunts);
445 NG_BRIDGE_COUNTER_ALLOC(recvInvalid);
446 NG_BRIDGE_COUNTER_ALLOC(xmitOctets);
447 NG_BRIDGE_COUNTER_ALLOC(xmitPackets);
448 NG_BRIDGE_COUNTER_ALLOC(xmitMulticasts);
449 NG_BRIDGE_COUNTER_ALLOC(xmitBroadcasts);
450 NG_BRIDGE_COUNTER_ALLOC(loopDrops);
451 NG_BRIDGE_COUNTER_ALLOC(memoryFailures);
452 #undef NG_BRIDGE_COUNTER_ALLOC
453
454 link->hook = hook;
455 if (isUplink) {
456 link->learnMac = 0;
457 link->sendUnknown = 1;
458 if (priv->numLinks == 0) /* if the first link is an uplink */
459 priv->sendUnknown = 0; /* switch to restrictive mode */
460 } else {
461 link->learnMac = 1;
462 link->sendUnknown = priv->sendUnknown;
463 }
464
465 NG_HOOK_SET_PRIVATE(hook, link);
466 priv->numLinks++;
467 return (0);
468
469 nomem:
470 free_unr(unit, linkNum);
471 ng_bridge_free_link(link);
472 return (ENOMEM);
473 }
474
475 /*
476 * Receive a control message
477 */
478 static void
ng_bridge_clear_link_stats(struct ng_bridge_link_kernel_stats * p)479 ng_bridge_clear_link_stats(struct ng_bridge_link_kernel_stats *p)
480 {
481 counter_u64_zero(p->recvOctets);
482 counter_u64_zero(p->recvPackets);
483 counter_u64_zero(p->recvMulticasts);
484 counter_u64_zero(p->recvBroadcasts);
485 counter_u64_zero(p->recvUnknown);
486 counter_u64_zero(p->recvRunts);
487 counter_u64_zero(p->recvInvalid);
488 counter_u64_zero(p->xmitOctets);
489 counter_u64_zero(p->xmitPackets);
490 counter_u64_zero(p->xmitMulticasts);
491 counter_u64_zero(p->xmitBroadcasts);
492 counter_u64_zero(p->loopDrops);
493 p->loopDetects = 0;
494 counter_u64_zero(p->memoryFailures);
495 }
496
497 static void
ng_bridge_free_link(link_p link)498 ng_bridge_free_link(link_p link)
499 {
500 counter_u64_free(link->stats.recvOctets);
501 counter_u64_free(link->stats.recvPackets);
502 counter_u64_free(link->stats.recvMulticasts);
503 counter_u64_free(link->stats.recvBroadcasts);
504 counter_u64_free(link->stats.recvUnknown);
505 counter_u64_free(link->stats.recvRunts);
506 counter_u64_free(link->stats.recvInvalid);
507 counter_u64_free(link->stats.xmitOctets);
508 counter_u64_free(link->stats.xmitPackets);
509 counter_u64_free(link->stats.xmitMulticasts);
510 counter_u64_free(link->stats.xmitBroadcasts);
511 counter_u64_free(link->stats.loopDrops);
512 counter_u64_free(link->stats.memoryFailures);
513 free(link, M_NETGRAPH_BRIDGE);
514 }
515
516 static int
ng_bridge_reset_link(hook_p hook,void * arg __unused)517 ng_bridge_reset_link(hook_p hook, void *arg __unused)
518 {
519 link_p priv = NG_HOOK_PRIVATE(hook);
520
521 priv->loopCount = 0;
522 ng_bridge_clear_link_stats(&priv->stats);
523 return (1);
524 }
525
526 static int
ng_bridge_rcvmsg(node_p node,item_p item,hook_p lasthook)527 ng_bridge_rcvmsg(node_p node, item_p item, hook_p lasthook)
528 {
529 const priv_p priv = NG_NODE_PRIVATE(node);
530 struct ng_mesg *resp = NULL;
531 int error = 0;
532 struct ng_mesg *msg;
533
534 NGI_GET_MSG(item, msg);
535 switch (msg->header.typecookie) {
536 case NGM_BRIDGE_COOKIE:
537 switch (msg->header.cmd) {
538 case NGM_BRIDGE_GET_CONFIG:
539 {
540 struct ng_bridge_config *conf;
541
542 NG_MKRESPONSE(resp, msg,
543 sizeof(struct ng_bridge_config), M_NOWAIT);
544 if (resp == NULL) {
545 error = ENOMEM;
546 break;
547 }
548 conf = (struct ng_bridge_config *)resp->data;
549 *conf = priv->conf; /* no sanity checking needed */
550 break;
551 }
552 case NGM_BRIDGE_SET_CONFIG:
553 {
554 struct ng_bridge_config *conf;
555
556 if (msg->header.arglen
557 != sizeof(struct ng_bridge_config)) {
558 error = EINVAL;
559 break;
560 }
561 conf = (struct ng_bridge_config *)msg->data;
562 priv->conf = *conf;
563 break;
564 }
565 case NGM_BRIDGE_RESET:
566 {
567 /* Flush all entries in the hash table */
568 ng_bridge_remove_hosts(priv, NULL);
569
570 /* Reset all loop detection counters and stats */
571 NG_NODE_FOREACH_HOOK(node, ng_bridge_reset_link, NULL);
572 break;
573 }
574 case NGM_BRIDGE_GET_STATS:
575 case NGM_BRIDGE_CLR_STATS:
576 case NGM_BRIDGE_GETCLR_STATS:
577 {
578 hook_p hook;
579 link_p link;
580 char linkName[NG_HOOKSIZ];
581 int linkNum;
582
583 /* Get link number */
584 if (msg->header.arglen != sizeof(u_int32_t)) {
585 error = EINVAL;
586 break;
587 }
588 linkNum = *((int32_t *)msg->data);
589 if (linkNum < 0)
590 snprintf(linkName, sizeof(linkName),
591 "%s%u", NG_BRIDGE_HOOK_UPLINK_PREFIX, -linkNum);
592 else
593 snprintf(linkName, sizeof(linkName),
594 "%s%u", NG_BRIDGE_HOOK_LINK_PREFIX, linkNum);
595
596 if ((hook = ng_findhook(node, linkName)) == NULL) {
597 error = ENOTCONN;
598 break;
599 }
600 link = NG_HOOK_PRIVATE(hook);
601
602 /* Get/clear stats */
603 if (msg->header.cmd != NGM_BRIDGE_CLR_STATS) {
604 struct ng_bridge_link_stats *rs;
605
606 NG_MKRESPONSE(resp, msg,
607 sizeof(link->stats), M_NOWAIT);
608 if (resp == NULL) {
609 error = ENOMEM;
610 break;
611 }
612 rs = (struct ng_bridge_link_stats *)resp->data;
613 #define FETCH(x) rs->x = counter_u64_fetch(link->stats.x)
614 FETCH(recvOctets);
615 FETCH(recvPackets);
616 FETCH(recvMulticasts);
617 FETCH(recvBroadcasts);
618 FETCH(recvUnknown);
619 FETCH(recvRunts);
620 FETCH(recvInvalid);
621 FETCH(xmitOctets);
622 FETCH(xmitPackets);
623 FETCH(xmitMulticasts);
624 FETCH(xmitBroadcasts);
625 FETCH(loopDrops);
626 rs->loopDetects = link->stats.loopDetects;
627 FETCH(memoryFailures);
628 #undef FETCH
629 }
630 if (msg->header.cmd != NGM_BRIDGE_GET_STATS)
631 ng_bridge_clear_link_stats(&link->stats);
632 break;
633 }
634 case NGM_BRIDGE_GET_TABLE:
635 {
636 struct ng_bridge_host_ary *ary;
637 struct ng_bridge_host *host;
638 int i = 0, bucket;
639
640 NG_MKRESPONSE(resp, msg, sizeof(*ary)
641 + (priv->numHosts * sizeof(*ary->hosts)), M_NOWAIT);
642 if (resp == NULL) {
643 error = ENOMEM;
644 break;
645 }
646 ary = (struct ng_bridge_host_ary *)resp->data;
647 ary->numHosts = priv->numHosts;
648 for (bucket = 0; bucket < priv->numBuckets; bucket++) {
649 SLIST_FOREACH(host, &priv->tab[bucket], next) {
650 memcpy(ary->hosts[i].addr,
651 host->addr,
652 sizeof(ary->hosts[i].addr));
653 ary->hosts[i].age = host->age;
654 ary->hosts[i].staleness = host->staleness;
655 strncpy(ary->hosts[i].hook,
656 NG_HOOK_NAME(host->link->hook),
657 sizeof(ary->hosts[i].hook));
658 i++;
659 }
660 }
661 break;
662 }
663 case NGM_BRIDGE_SET_PERSISTENT:
664 {
665 priv->persistent = 1;
666 break;
667 }
668 case NGM_BRIDGE_MOVE_HOST:
669 {
670 struct ng_bridge_move_host *mh;
671 hook_p hook;
672
673 if (msg->header.arglen < sizeof(*mh)) {
674 error = EINVAL;
675 break;
676 }
677 mh = (struct ng_bridge_move_host *)msg->data;
678 hook = (mh->hook[0] == 0)
679 ? lasthook
680 : ng_findhook(node, mh->hook);
681 if (hook == NULL) {
682 error = ENOENT;
683 break;
684 }
685 error = ng_bridge_put(priv, mh->addr, NG_HOOK_PRIVATE(hook));
686 break;
687 }
688 default:
689 error = EINVAL;
690 break;
691 }
692 break;
693 default:
694 error = EINVAL;
695 break;
696 }
697
698 /* Done */
699 NG_RESPOND_MSG(error, node, item, resp);
700 NG_FREE_MSG(msg);
701 return (error);
702 }
703
704 /*
705 * Receive data on a hook
706 */
707 struct ng_bridge_send_ctx {
708 link_p foundFirst, incoming;
709 struct mbuf * m;
710 int manycast, error;
711 };
712
713 /*
714 * Update stats and send out
715 */
716 static inline int
ng_bridge_send_data(link_cp dst,int manycast,struct mbuf * m,item_p item)717 ng_bridge_send_data(link_cp dst, int manycast, struct mbuf *m, item_p item) {
718 int error = 0;
719 size_t len = m->m_pkthdr.len;
720
721 if(item != NULL)
722 NG_FWD_NEW_DATA(error, item, dst->hook, m);
723 else
724 NG_SEND_DATA_ONLY(error, dst->hook, m);
725
726 if (error) {
727 if (error == ENOMEM)
728 counter_u64_add(dst->stats.memoryFailures, 1);
729 /* The packet is still ours */
730 if (item != NULL)
731 NG_FREE_ITEM(item);
732 if (m != NULL)
733 NG_FREE_M(m);
734 return (error);
735 }
736
737 counter_u64_add(dst->stats.xmitPackets, 1);
738 counter_u64_add(dst->stats.xmitOctets, len);
739 switch (manycast) {
740 default: /* unknown unicast */
741 break;
742 case 1: /* multicast */
743 counter_u64_add(dst->stats.xmitMulticasts, 1);
744 break;
745 case 2: /* broadcast */
746 counter_u64_add(dst->stats.xmitBroadcasts, 1);
747 break;
748 }
749 return (0);
750 }
751
752 /*
753 * Loop body for sending to multiple destinations
754 * return 0 to stop looping
755 */
756 static int
ng_bridge_send_ctx(hook_p dst,void * arg)757 ng_bridge_send_ctx(hook_p dst, void *arg)
758 {
759 struct ng_bridge_send_ctx *ctx = arg;
760 link_p destLink = NG_HOOK_PRIVATE(dst);
761 struct mbuf *m2 = NULL;
762 int error = 0;
763
764 /* Skip incoming link */
765 if (destLink == ctx->incoming) {
766 return (1);
767 }
768
769 /* Skip sending unknowns to undesired links */
770 if (!ctx->manycast && !destLink->sendUnknown)
771 return (1);
772
773 if (ctx->foundFirst == NULL) {
774 /*
775 * This is the first usable link we have found.
776 * Reserve it for the originals.
777 * If we never find another we save a copy.
778 */
779 ctx->foundFirst = destLink;
780 return (1);
781 }
782
783 /*
784 * It's usable link but not the reserved (first) one.
785 * Copy mbuf info for sending.
786 */
787 m2 = m_dup(ctx->m, M_NOWAIT);
788 if (m2 == NULL) {
789 counter_u64_add(ctx->incoming->stats.memoryFailures, 1);
790 ctx->error = ENOBUFS;
791 return (0); /* abort loop, do not try again and again */
792 }
793
794 /* Send packet */
795 error = ng_bridge_send_data(destLink, ctx->manycast, m2, NULL);
796 if (error)
797 ctx->error = error;
798 return (1);
799 }
800
801 static int
ng_bridge_rcvdata(hook_p hook,item_p item)802 ng_bridge_rcvdata(hook_p hook, item_p item)
803 {
804 const node_p node = NG_HOOK_NODE(hook);
805 const priv_p priv = NG_NODE_PRIVATE(node);
806 struct ng_bridge_host *host;
807 struct ether_header *eh;
808 struct ng_bridge_send_ctx ctx = { 0 };
809
810 NGI_GET_M(item, ctx.m);
811
812 ctx.incoming = NG_HOOK_PRIVATE(hook);
813 /* Sanity check packet and pull up header */
814 if (ctx.m->m_pkthdr.len < ETHER_HDR_LEN) {
815 counter_u64_add(ctx.incoming->stats.recvRunts, 1);
816 NG_FREE_ITEM(item);
817 NG_FREE_M(ctx.m);
818 return (EINVAL);
819 }
820 if (ctx.m->m_len < ETHER_HDR_LEN && !(ctx.m = m_pullup(ctx.m, ETHER_HDR_LEN))) {
821 counter_u64_add(ctx.incoming->stats.memoryFailures, 1);
822 NG_FREE_ITEM(item);
823 return (ENOBUFS);
824 }
825 eh = mtod(ctx.m, struct ether_header *);
826 if ((eh->ether_shost[0] & 1) != 0) {
827 counter_u64_add(ctx.incoming->stats.recvInvalid, 1);
828 NG_FREE_ITEM(item);
829 NG_FREE_M(ctx.m);
830 return (EINVAL);
831 }
832
833 /* Is link disabled due to a loopback condition? */
834 if (ctx.incoming->loopCount != 0) {
835 counter_u64_add(ctx.incoming->stats.loopDrops, 1);
836 NG_FREE_ITEM(item);
837 NG_FREE_M(ctx.m);
838 return (ELOOP);
839 }
840
841 /* Update stats */
842 counter_u64_add(ctx.incoming->stats.recvPackets, 1);
843 counter_u64_add(ctx.incoming->stats.recvOctets, ctx.m->m_pkthdr.len);
844 if ((ctx.manycast = (eh->ether_dhost[0] & 1)) != 0) {
845 if (ETHER_EQUAL(eh->ether_dhost, ng_bridge_bcast_addr)) {
846 counter_u64_add(ctx.incoming->stats.recvBroadcasts, 1);
847 ctx.manycast = 2;
848 } else
849 counter_u64_add(ctx.incoming->stats.recvMulticasts, 1);
850 }
851
852 /* Look up packet's source Ethernet address in hashtable */
853 if ((host = ng_bridge_get(priv, eh->ether_shost)) != NULL)
854 /* Update time since last heard from this host.
855 * This is safe without locking, because it's
856 * the only operation during shared access.
857 */
858 if (__predict_false(host->staleness > 0))
859 host->staleness = 0;
860
861 /*
862 * learnMac is 0 on uplink: neither insert a new host nor
863 * move an existing one from packets received there.
864 */
865 if (ctx.incoming->learnMac &&
866 (host == NULL || host->link != ctx.incoming)) {
867 struct ng_mesg *msg;
868 struct ng_bridge_move_host *mh;
869 int error = 0;
870
871 NG_MKMESSAGE(msg, NGM_BRIDGE_COOKIE, NGM_BRIDGE_MOVE_HOST,
872 sizeof(*mh), M_NOWAIT);
873 if (msg == NULL) {
874 counter_u64_add(ctx.incoming->stats.memoryFailures, 1);
875 NG_FREE_ITEM(item);
876 NG_FREE_M(ctx.m);
877 return (ENOMEM);
878 }
879 mh = (struct ng_bridge_move_host *)msg->data;
880 strncpy(mh->hook, NG_HOOK_NAME(ctx.incoming->hook),
881 sizeof(mh->hook));
882 memcpy(mh->addr, eh->ether_shost, sizeof(mh->addr));
883 NG_SEND_MSG_ID(error, node, msg, NG_NODE_ID(node),
884 NG_NODE_ID(node));
885 if (error)
886 counter_u64_add(ctx.incoming->stats.memoryFailures, 1);
887 }
888
889 if (host != NULL && host->link != ctx.incoming) {
890 if (host->age < priv->conf.minStableAge) {
891 /* Drop packet on instable links */
892 counter_u64_add(ctx.incoming->stats.loopDrops, 1);
893 NG_FREE_ITEM(item);
894 NG_FREE_M(ctx.m);
895 return (ELOOP);
896 }
897 }
898
899 /*
900 * If unicast and destination host known, deliver to host's link,
901 * unless it is the same link as the packet came in on.
902 */
903 if (!ctx.manycast) {
904 /* Determine packet destination link */
905 if ((host = ng_bridge_get(priv, eh->ether_dhost)) != NULL) {
906 link_p destLink = host->link;
907
908 /* If destination same as incoming link, do nothing */
909 if (destLink == ctx.incoming) {
910 NG_FREE_ITEM(item);
911 NG_FREE_M(ctx.m);
912 return (0);
913 }
914
915 /* Deliver packet out the destination link */
916 return (ng_bridge_send_data(destLink, ctx.manycast, ctx.m, item));
917 }
918
919 /* Destination host is not known */
920 counter_u64_add(ctx.incoming->stats.recvUnknown, 1);
921 }
922
923 /* Distribute unknown, multicast, broadcast pkts to all other links */
924 NG_NODE_FOREACH_HOOK(node, ng_bridge_send_ctx, &ctx);
925
926 /* Finally send out on the first link found */
927 if (ctx.foundFirst != NULL) {
928 int error = ng_bridge_send_data(ctx.foundFirst, ctx.manycast, ctx.m, item);
929 if (error)
930 ctx.error = error;
931 } else { /* nothing to send at all */
932 NG_FREE_ITEM(item);
933 NG_FREE_M(ctx.m);
934 }
935
936 return (ctx.error);
937 }
938
939 /*
940 * Shutdown node
941 */
942 static int
ng_bridge_shutdown(node_p node)943 ng_bridge_shutdown(node_p node)
944 {
945 const priv_p priv = NG_NODE_PRIVATE(node);
946
947 /*
948 * Shut down everything including the timer. Even if the
949 * callout has already been dequeued and is about to be
950 * run, ng_bridge_timeout() won't be fired as the node
951 * is already marked NGF_INVALID, so we're safe to free
952 * the node now.
953 */
954 KASSERT(priv->numLinks == 0 && priv->numHosts == 0,
955 ("%s: numLinks=%d numHosts=%d",
956 __func__, priv->numLinks, priv->numHosts));
957 ng_uncallout(&priv->timer, node);
958 delete_unrhdr(priv->linkUnit);
959 delete_unrhdr(priv->uplinkUnit);
960 NG_NODE_SET_PRIVATE(node, NULL);
961 NG_NODE_UNREF(node);
962 free(priv->tab, M_NETGRAPH_BRIDGE);
963 free(priv, M_NETGRAPH_BRIDGE);
964 return (0);
965 }
966
967 /*
968 * Hook disconnection.
969 */
970 static int
ng_bridge_disconnect(hook_p hook)971 ng_bridge_disconnect(hook_p hook)
972 {
973 char *name = NG_HOOK_NAME(hook);
974 const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
975 link_p link = NG_HOOK_PRIVATE(hook);
976 const struct ng_link_prefix *pfx = ng_get_link_prefix(name);
977 uint32_t linkNum;
978
979 /* Remove all hosts associated with this link */
980 ng_bridge_remove_hosts(priv, link);
981
982 /* Free associated link information */
983 ng_bridge_free_link(link);
984 priv->numLinks--;
985
986 linkNum = strtoul(name + pfx->len, NULL, 10);
987 free_unr(pfx == &link_pfx ? priv->linkUnit: priv->uplinkUnit, linkNum);
988
989 /* If no more hooks, go away */
990 if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0)
991 && (NG_NODE_IS_VALID(NG_HOOK_NODE(hook)))
992 && !priv->persistent) {
993 ng_rmnode_self(NG_HOOK_NODE(hook));
994 }
995 return (0);
996 }
997
998 /******************************************************************
999 HASH TABLE FUNCTIONS
1000 ******************************************************************/
1001
1002 /*
1003 * Hash algorithm
1004 */
1005 #define HASH(addr,mask) ( (((const u_int16_t *)(addr))[0] \
1006 ^ ((const u_int16_t *)(addr))[1] \
1007 ^ ((const u_int16_t *)(addr))[2]) & (mask) )
1008
1009 /*
1010 * Find a host entry in the table.
1011 */
1012 static struct ng_bridge_host *
ng_bridge_get(priv_cp priv,const u_char * addr)1013 ng_bridge_get(priv_cp priv, const u_char *addr)
1014 {
1015 const int bucket = HASH(addr, priv->hashMask);
1016 struct ng_bridge_host *host;
1017
1018 SLIST_FOREACH(host, &priv->tab[bucket], next) {
1019 if (ETHER_EQUAL(host->addr, addr))
1020 return (host);
1021 }
1022 return (NULL);
1023 }
1024
1025 /*
1026 * Add a host entry to the table. If it already exists, move it
1027 * to the new link. Returns 0 on success.
1028 */
1029 static int
ng_bridge_put(priv_p priv,const u_char * addr,link_p link)1030 ng_bridge_put(priv_p priv, const u_char *addr, link_p link)
1031 {
1032 const int bucket = HASH(addr, priv->hashMask);
1033 struct ng_bridge_host *host;
1034
1035 if ((host = ng_bridge_get(priv, addr)) != NULL) {
1036 /* Host already on the correct link? */
1037 if (host->link == link)
1038 return 0;
1039
1040 /* Move old host over to new link */
1041 if (host->age >= priv->conf.minStableAge) {
1042 host->link = link;
1043 host->age = 0;
1044 return (0);
1045 }
1046 /*
1047 * If the host was recently moved to the old link and
1048 * it's now jumping to a new link, declare a loopback
1049 * condition.
1050 */
1051 if (priv->conf.debugLevel >= 2)
1052 log(LOG_WARNING, "ng_bridge: %s:"
1053 " loopback detected on %s\n",
1054 ng_bridge_nodename(priv->node),
1055 NG_HOOK_NAME(link->hook));
1056
1057 /* Mark link as linka non grata */
1058 link->loopCount = priv->conf.loopTimeout;
1059 link->stats.loopDetects++;
1060
1061 /* Forget all hosts on this link */
1062 ng_bridge_remove_hosts(priv, link);
1063 return (ELOOP);
1064 }
1065
1066 /* Allocate and initialize new hashtable entry */
1067 host = malloc(sizeof(*host), M_NETGRAPH_BRIDGE, M_NOWAIT);
1068 if (host == NULL)
1069 return (ENOMEM);
1070 bcopy(addr, host->addr, ETHER_ADDR_LEN);
1071 host->link = link;
1072 host->staleness = 0;
1073 host->age = 0;
1074
1075 /* Add new element to hash bucket */
1076 SLIST_INSERT_HEAD(&priv->tab[bucket], host, next);
1077 priv->numHosts++;
1078
1079 /* Resize table if necessary */
1080 ng_bridge_rehash(priv);
1081 return (0);
1082 }
1083
1084 /*
1085 * Resize the hash table. We try to maintain the number of buckets
1086 * such that the load factor is in the range 0.25 to 1.0.
1087 *
1088 * If we can't get the new memory then we silently fail. This is OK
1089 * because things will still work and we'll try again soon anyway.
1090 */
1091 static void
ng_bridge_rehash(priv_p priv)1092 ng_bridge_rehash(priv_p priv)
1093 {
1094 struct ng_bridge_bucket *newTab;
1095 int oldBucket, newBucket;
1096 int newNumBuckets;
1097 u_int newMask;
1098
1099 /* Is table too full or too empty? */
1100 if (priv->numHosts > priv->numBuckets
1101 && (priv->numBuckets << 1) <= MAX_BUCKETS)
1102 newNumBuckets = priv->numBuckets << 1;
1103 else if (priv->numHosts < (priv->numBuckets >> 2)
1104 && (priv->numBuckets >> 2) >= MIN_BUCKETS)
1105 newNumBuckets = priv->numBuckets >> 2;
1106 else
1107 return;
1108 newMask = newNumBuckets - 1;
1109
1110 /* Allocate and initialize new table */
1111 newTab = malloc(newNumBuckets * sizeof(*newTab),
1112 M_NETGRAPH_BRIDGE, M_NOWAIT | M_ZERO);
1113 if (newTab == NULL)
1114 return;
1115
1116 /* Move all entries from old table to new table */
1117 for (oldBucket = 0; oldBucket < priv->numBuckets; oldBucket++) {
1118 struct ng_bridge_bucket *const oldList = &priv->tab[oldBucket];
1119
1120 while (!SLIST_EMPTY(oldList)) {
1121 struct ng_bridge_host *const host
1122 = SLIST_FIRST(oldList);
1123
1124 SLIST_REMOVE_HEAD(oldList, next);
1125 newBucket = HASH(host->addr, newMask);
1126 SLIST_INSERT_HEAD(&newTab[newBucket], host, next);
1127 }
1128 }
1129
1130 /* Replace old table with new one */
1131 if (priv->conf.debugLevel >= 3) {
1132 log(LOG_INFO, "ng_bridge: %s: table size %d -> %d\n",
1133 ng_bridge_nodename(priv->node),
1134 priv->numBuckets, newNumBuckets);
1135 }
1136 free(priv->tab, M_NETGRAPH_BRIDGE);
1137 priv->numBuckets = newNumBuckets;
1138 priv->hashMask = newMask;
1139 priv->tab = newTab;
1140 return;
1141 }
1142
1143 /******************************************************************
1144 MISC FUNCTIONS
1145 ******************************************************************/
1146
1147 static const struct ng_link_prefix *
ng_get_link_prefix(const char * name)1148 ng_get_link_prefix(const char *name)
1149 {
1150 static const struct ng_link_prefix *pfxs[] =
1151 { &link_pfx, &uplink_pfx, };
1152
1153 for (u_int i = 0; i < nitems(pfxs); i++)
1154 if (strncmp(pfxs[i]->prefix, name, pfxs[i]->len) == 0)
1155 return (pfxs[i]);
1156
1157 return (NULL);
1158 }
1159
1160 /*
1161 * Remove all hosts associated with a specific link from the hashtable.
1162 * If linkNum == -1, then remove all hosts in the table.
1163 */
1164 static void
ng_bridge_remove_hosts(priv_p priv,link_p link)1165 ng_bridge_remove_hosts(priv_p priv, link_p link)
1166 {
1167 int bucket;
1168
1169 for (bucket = 0; bucket < priv->numBuckets; bucket++) {
1170 struct ng_bridge_host **hptr = &SLIST_FIRST(&priv->tab[bucket]);
1171
1172 while (*hptr != NULL) {
1173 struct ng_bridge_host *const host = *hptr;
1174
1175 if (link == NULL || host->link == link) {
1176 *hptr = SLIST_NEXT(host, next);
1177 free(host, M_NETGRAPH_BRIDGE);
1178 priv->numHosts--;
1179 } else
1180 hptr = &SLIST_NEXT(host, next);
1181 }
1182 }
1183 }
1184
1185 /*
1186 * Handle our once-per-second timeout event. We do two things:
1187 * we decrement link->loopCount for those links being muted due to
1188 * a detected loopback condition, and we remove any hosts from
1189 * the hashtable whom we haven't heard from in a long while.
1190 */
1191 static int
ng_bridge_unmute(hook_p hook,void * arg)1192 ng_bridge_unmute(hook_p hook, void *arg)
1193 {
1194 link_p link = NG_HOOK_PRIVATE(hook);
1195 node_p node = NG_HOOK_NODE(hook);
1196 priv_p priv = NG_NODE_PRIVATE(node);
1197 int *counter = arg;
1198
1199 if (link->loopCount != 0) {
1200 link->loopCount--;
1201 if (link->loopCount == 0 && priv->conf.debugLevel >= 2) {
1202 log(LOG_INFO, "ng_bridge: %s:"
1203 " restoring looped back %s\n",
1204 ng_bridge_nodename(node), NG_HOOK_NAME(hook));
1205 }
1206 }
1207 (*counter)++;
1208 return (1);
1209 }
1210
1211 static void
ng_bridge_timeout(node_p node,hook_p hook,void * arg1,int arg2)1212 ng_bridge_timeout(node_p node, hook_p hook, void *arg1, int arg2)
1213 {
1214 const priv_p priv = NG_NODE_PRIVATE(node);
1215 int bucket;
1216 int counter = 0;
1217
1218 /* Update host time counters and remove stale entries */
1219 for (bucket = 0; bucket < priv->numBuckets; bucket++) {
1220 struct ng_bridge_host **hptr = &SLIST_FIRST(&priv->tab[bucket]);
1221
1222 while (*hptr != NULL) {
1223 struct ng_bridge_host *const host = *hptr;
1224
1225 /* Remove hosts we haven't heard from in a while */
1226 if (++host->staleness >= priv->conf.maxStaleness) {
1227 *hptr = SLIST_NEXT(host, next);
1228 free(host, M_NETGRAPH_BRIDGE);
1229 priv->numHosts--;
1230 } else {
1231 if (host->age < 0xffff)
1232 host->age++;
1233 hptr = &SLIST_NEXT(host, next);
1234 counter++;
1235 }
1236 }
1237 }
1238 KASSERT(priv->numHosts == counter,
1239 ("%s: hosts: %d != %d", __func__, priv->numHosts, counter));
1240
1241 /* Decrease table size if necessary */
1242 ng_bridge_rehash(priv);
1243
1244 /* Decrease loop counter on muted looped back links */
1245 counter = 0;
1246 NG_NODE_FOREACH_HOOK(node, ng_bridge_unmute, &counter);
1247 KASSERT(priv->numLinks == counter,
1248 ("%s: links: %d != %d", __func__, priv->numLinks, counter));
1249
1250 /* Register a new timeout, keeping the existing node reference */
1251 ng_callout(&priv->timer, node, NULL, hz, ng_bridge_timeout, NULL, 0);
1252 }
1253
1254 /*
1255 * Return node's "name", even if it doesn't have one.
1256 */
1257 static const char *
ng_bridge_nodename(node_cp node)1258 ng_bridge_nodename(node_cp node)
1259 {
1260 static char name[NG_NODESIZ];
1261
1262 if (NG_NODE_HAS_NAME(node))
1263 snprintf(name, sizeof(name), "%s", NG_NODE_NAME(node));
1264 else
1265 snprintf(name, sizeof(name), "[%x]", ng_node2ID(node));
1266 return name;
1267 }
1268