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10 * without modifications are expressly permitted by Whistle Communications;
11 * provided, however, that:
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37 * Author: Archie Cobbs <archie@freebsd.org>
39 * $FreeBSD: src/sys/netgraph/ng_bridge.c,v 1.1.2.5 2002/07/02 23:44:02 archie Exp $
40 * $DragonFly: src/sys/netgraph/bridge/ng_bridge.c,v 1.10 2007/06/03 20:51:12 dillon Exp $
44 * ng_bridge(4) netgraph node type
46 * The node performs standard intelligent Ethernet bridging over
47 * each of its connected hooks, or links. A simple loop detection
48 * algorithm is included which disables a link for priv->conf.loopTimeout
49 * seconds when a host is seen to have jumped from one link to
50 * another within priv->conf.minStableAge seconds.
52 * We keep a hashtable that maps Ethernet addresses to host info,
53 * which is contained in struct ng_bridge_host's. These structures
54 * tell us on which link the host may be found. A host's entry will
55 * expire after priv->conf.maxStaleness seconds.
57 * This node is optimzed for stable networks, where machines jump
58 * from one port to the other only rarely.
61 #include <sys/param.h>
62 #include <sys/systm.h>
63 #include <sys/kernel.h>
64 #include <sys/malloc.h>
66 #include <sys/errno.h>
67 #include <sys/syslog.h>
68 #include <sys/socket.h>
69 #include <sys/ctype.h>
70 #include <sys/thread2.h>
73 #include <net/ethernet.h>
75 #include <netinet/in.h>
76 #include <net/ipfw/ip_fw.h>
78 #include <netgraph/ng_message.h>
79 #include <netgraph/netgraph.h>
80 #include <netgraph/ng_parse.h>
81 #include "ng_bridge.h"
82 #include <netgraph/ether/ng_ether.h>
84 /* Per-link private data */
85 struct ng_bridge_link {
86 hook_p hook; /* netgraph hook */
87 u_int16_t loopCount; /* loop ignore timer */
88 struct ng_bridge_link_stats stats; /* link stats */
91 /* Per-node private data */
92 struct ng_bridge_private {
93 struct ng_bridge_bucket *tab; /* hash table bucket array */
94 struct ng_bridge_link *links[NG_BRIDGE_MAX_LINKS];
95 struct ng_bridge_config conf; /* node configuration */
96 node_p node; /* netgraph node */
97 u_int numHosts; /* num entries in table */
98 u_int numBuckets; /* num buckets in table */
99 u_int hashMask; /* numBuckets - 1 */
100 int numLinks; /* num connected links */
101 struct callout timer; /* one second periodic timer */
103 typedef struct ng_bridge_private *priv_p;
105 /* Information about a host, stored in a hash table entry */
106 struct ng_bridge_hent {
107 struct ng_bridge_host host; /* actual host info */
108 SLIST_ENTRY(ng_bridge_hent) next; /* next entry in bucket */
111 /* Hash table bucket declaration */
112 SLIST_HEAD(ng_bridge_bucket, ng_bridge_hent);
114 /* Netgraph node methods */
115 static ng_constructor_t ng_bridge_constructor;
116 static ng_rcvmsg_t ng_bridge_rcvmsg;
117 static ng_shutdown_t ng_bridge_rmnode;
118 static ng_newhook_t ng_bridge_newhook;
119 static ng_rcvdata_t ng_bridge_rcvdata;
120 static ng_disconnect_t ng_bridge_disconnect;
122 /* Other internal functions */
123 static struct ng_bridge_host *ng_bridge_get(priv_p priv, const u_char *addr);
124 static int ng_bridge_put(priv_p priv, const u_char *addr, int linkNum);
125 static void ng_bridge_rehash(priv_p priv);
126 static void ng_bridge_remove_hosts(priv_p priv, int linkNum);
127 static void ng_bridge_timeout(void *arg);
128 static const char *ng_bridge_nodename(node_p node);
130 /* Ethernet broadcast */
131 static const u_char ng_bridge_bcast_addr[ETHER_ADDR_LEN] =
132 { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
134 /* Store each hook's link number in the private field */
135 #define LINK_NUM(hook) (*(u_int16_t *)(&(hook)->private))
137 /* Compare Ethernet addresses using 32 and 16 bit words instead of bytewise */
138 #define ETHER_EQUAL(a,b) (((const u_int32_t *)(a))[0] \
139 == ((const u_int32_t *)(b))[0] \
140 && ((const u_int16_t *)(a))[2] \
141 == ((const u_int16_t *)(b))[2])
143 /* Minimum and maximum number of hash buckets. Must be a power of two. */
144 #define MIN_BUCKETS (1 << 5) /* 32 */
145 #define MAX_BUCKETS (1 << 14) /* 16384 */
147 /* Configuration default values */
148 #define DEFAULT_LOOP_TIMEOUT 60
149 #define DEFAULT_MAX_STALENESS (15 * 60) /* same as ARP timeout */
150 #define DEFAULT_MIN_STABLE_AGE 1
152 /******************************************************************
154 ******************************************************************/
157 * How to determine the length of the table returned by NGM_BRIDGE_GET_TABLE
160 ng_bridge_getTableLength(const struct ng_parse_type *type,
161 const u_char *start, const u_char *buf)
163 const struct ng_bridge_host_ary *const hary
164 = (const struct ng_bridge_host_ary *)(buf - sizeof(u_int32_t));
166 return hary->numHosts;
169 /* Parse type for struct ng_bridge_host_ary */
170 static const struct ng_parse_struct_field ng_bridge_host_type_fields[]
171 = NG_BRIDGE_HOST_TYPE_INFO(&ng_ether_enaddr_type);
172 static const struct ng_parse_type ng_bridge_host_type = {
173 &ng_parse_struct_type,
174 &ng_bridge_host_type_fields
176 static const struct ng_parse_array_info ng_bridge_hary_type_info = {
177 &ng_bridge_host_type,
178 ng_bridge_getTableLength
180 static const struct ng_parse_type ng_bridge_hary_type = {
181 &ng_parse_array_type,
182 &ng_bridge_hary_type_info
184 static const struct ng_parse_struct_field ng_bridge_host_ary_type_fields[]
185 = NG_BRIDGE_HOST_ARY_TYPE_INFO(&ng_bridge_hary_type);
186 static const struct ng_parse_type ng_bridge_host_ary_type = {
187 &ng_parse_struct_type,
188 &ng_bridge_host_ary_type_fields
191 /* Parse type for struct ng_bridge_config */
192 static const struct ng_parse_fixedarray_info ng_bridge_ipfwary_type_info = {
193 &ng_parse_uint8_type,
196 static const struct ng_parse_type ng_bridge_ipfwary_type = {
197 &ng_parse_fixedarray_type,
198 &ng_bridge_ipfwary_type_info
200 static const struct ng_parse_struct_field ng_bridge_config_type_fields[]
201 = NG_BRIDGE_CONFIG_TYPE_INFO(&ng_bridge_ipfwary_type);
202 static const struct ng_parse_type ng_bridge_config_type = {
203 &ng_parse_struct_type,
204 &ng_bridge_config_type_fields
207 /* Parse type for struct ng_bridge_link_stat */
208 static const struct ng_parse_struct_field ng_bridge_stats_type_fields[]
209 = NG_BRIDGE_STATS_TYPE_INFO;
210 static const struct ng_parse_type ng_bridge_stats_type = {
211 &ng_parse_struct_type,
212 &ng_bridge_stats_type_fields
215 /* List of commands and how to convert arguments to/from ASCII */
216 static const struct ng_cmdlist ng_bridge_cmdlist[] = {
219 NGM_BRIDGE_SET_CONFIG,
221 &ng_bridge_config_type,
226 NGM_BRIDGE_GET_CONFIG,
229 &ng_bridge_config_type
240 NGM_BRIDGE_GET_STATS,
242 &ng_parse_uint32_type,
243 &ng_bridge_stats_type
247 NGM_BRIDGE_CLR_STATS,
249 &ng_parse_uint32_type,
254 NGM_BRIDGE_GETCLR_STATS,
256 &ng_parse_uint32_type,
257 &ng_bridge_stats_type
261 NGM_BRIDGE_GET_TABLE,
264 &ng_bridge_host_ary_type
269 /* Node type descriptor */
270 static struct ng_type ng_bridge_typestruct = {
274 ng_bridge_constructor,
282 ng_bridge_disconnect,
285 NETGRAPH_INIT(bridge, &ng_bridge_typestruct);
287 /* Depend on ng_ether so we can use the Ethernet parse type */
288 MODULE_DEPEND(ng_bridge, ng_ether, 1, 1, 1);
290 /******************************************************************
291 NETGRAPH NODE METHODS
292 ******************************************************************/
298 ng_bridge_constructor(node_p *nodep)
303 /* Allocate and initialize private info */
304 MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_NOWAIT);
307 bzero(priv, sizeof(*priv));
308 callout_init(&priv->timer);
310 /* Allocate and initialize hash table, etc. */
311 MALLOC(priv->tab, struct ng_bridge_bucket *,
312 MIN_BUCKETS * sizeof(*priv->tab), M_NETGRAPH, M_NOWAIT);
313 if (priv->tab == NULL) {
314 FREE(priv, M_NETGRAPH);
317 bzero(priv->tab, MIN_BUCKETS * sizeof(*priv->tab)); /* init SLIST's */
318 priv->numBuckets = MIN_BUCKETS;
319 priv->hashMask = MIN_BUCKETS - 1;
320 priv->conf.debugLevel = 1;
321 priv->conf.loopTimeout = DEFAULT_LOOP_TIMEOUT;
322 priv->conf.maxStaleness = DEFAULT_MAX_STALENESS;
323 priv->conf.minStableAge = DEFAULT_MIN_STABLE_AGE;
325 /* Call superclass constructor */
326 if ((error = ng_make_node_common(&ng_bridge_typestruct, nodep))) {
327 FREE(priv, M_NETGRAPH);
330 (*nodep)->private = priv;
333 /* Start timer; timer is always running while node is alive */
334 callout_reset(&priv->timer, hz, ng_bridge_timeout, priv->node);
341 * Method for attaching a new hook
344 ng_bridge_newhook(node_p node, hook_p hook, const char *name)
346 const priv_p priv = node->private;
348 /* Check for a link hook */
349 if (strncmp(name, NG_BRIDGE_HOOK_LINK_PREFIX,
350 strlen(NG_BRIDGE_HOOK_LINK_PREFIX)) == 0) {
355 cp = name + strlen(NG_BRIDGE_HOOK_LINK_PREFIX);
356 if (!isdigit(*cp) || (cp[0] == '0' && cp[1] != '\0'))
358 linkNum = strtoul(cp, &eptr, 10);
359 if (*eptr != '\0' || linkNum >= NG_BRIDGE_MAX_LINKS)
361 if (priv->links[linkNum] != NULL)
363 MALLOC(priv->links[linkNum], struct ng_bridge_link *,
364 sizeof(*priv->links[linkNum]), M_NETGRAPH, M_NOWAIT);
365 if (priv->links[linkNum] == NULL)
367 bzero(priv->links[linkNum], sizeof(*priv->links[linkNum]));
368 priv->links[linkNum]->hook = hook;
369 LINK_NUM(hook) = linkNum;
374 /* Unknown hook name */
379 * Receive a control message
382 ng_bridge_rcvmsg(node_p node, struct ng_mesg *msg,
383 const char *retaddr, struct ng_mesg **rptr)
385 const priv_p priv = node->private;
386 struct ng_mesg *resp = NULL;
389 switch (msg->header.typecookie) {
390 case NGM_BRIDGE_COOKIE:
391 switch (msg->header.cmd) {
392 case NGM_BRIDGE_GET_CONFIG:
394 struct ng_bridge_config *conf;
396 NG_MKRESPONSE(resp, msg,
397 sizeof(struct ng_bridge_config), M_NOWAIT);
402 conf = (struct ng_bridge_config *)resp->data;
403 *conf = priv->conf; /* no sanity checking needed */
406 case NGM_BRIDGE_SET_CONFIG:
408 struct ng_bridge_config *conf;
411 if (msg->header.arglen
412 != sizeof(struct ng_bridge_config)) {
416 conf = (struct ng_bridge_config *)msg->data;
418 for (i = 0; i < NG_BRIDGE_MAX_LINKS; i++)
419 priv->conf.ipfw[i] = !!priv->conf.ipfw[i];
422 case NGM_BRIDGE_RESET:
426 /* Flush all entries in the hash table */
427 ng_bridge_remove_hosts(priv, -1);
429 /* Reset all loop detection counters and stats */
430 for (i = 0; i < NG_BRIDGE_MAX_LINKS; i++) {
431 if (priv->links[i] == NULL)
433 priv->links[i]->loopCount = 0;
434 bzero(&priv->links[i]->stats,
435 sizeof(priv->links[i]->stats));
439 case NGM_BRIDGE_GET_STATS:
440 case NGM_BRIDGE_CLR_STATS:
441 case NGM_BRIDGE_GETCLR_STATS:
443 struct ng_bridge_link *link;
446 /* Get link number */
447 if (msg->header.arglen != sizeof(u_int32_t)) {
451 linkNum = *((u_int32_t *)msg->data);
452 if (linkNum < 0 || linkNum >= NG_BRIDGE_MAX_LINKS) {
456 if ((link = priv->links[linkNum]) == NULL) {
461 /* Get/clear stats */
462 if (msg->header.cmd != NGM_BRIDGE_CLR_STATS) {
463 NG_MKRESPONSE(resp, msg,
464 sizeof(link->stats), M_NOWAIT);
470 resp->data, sizeof(link->stats));
472 if (msg->header.cmd != NGM_BRIDGE_GET_STATS)
473 bzero(&link->stats, sizeof(link->stats));
476 case NGM_BRIDGE_GET_TABLE:
478 struct ng_bridge_host_ary *ary;
479 struct ng_bridge_hent *hent;
482 NG_MKRESPONSE(resp, msg, sizeof(*ary)
483 + (priv->numHosts * sizeof(*ary->hosts)), M_NOWAIT);
488 ary = (struct ng_bridge_host_ary *)resp->data;
489 ary->numHosts = priv->numHosts;
490 for (bucket = 0; bucket < priv->numBuckets; bucket++) {
491 SLIST_FOREACH(hent, &priv->tab[bucket], next)
492 ary->hosts[i++] = hent->host;
509 else if (resp != NULL)
510 FREE(resp, M_NETGRAPH);
511 FREE(msg, M_NETGRAPH);
516 * Receive data on a hook
519 ng_bridge_rcvdata(hook_p hook, struct mbuf *m, meta_p meta)
521 const node_p node = hook->node;
522 const priv_p priv = node->private;
523 struct ng_bridge_host *host;
524 struct ng_bridge_link *link;
525 struct ether_header *eh;
526 int error = 0, linkNum;
529 /* Get link number */
530 linkNum = LINK_NUM(hook);
531 KASSERT(linkNum >= 0 && linkNum < NG_BRIDGE_MAX_LINKS,
532 ("%s: linkNum=%u", __func__, linkNum));
533 link = priv->links[linkNum];
534 KASSERT(link != NULL, ("%s: link%d null", __func__, linkNum));
536 /* Sanity check packet and pull up header */
537 if (m->m_pkthdr.len < ETHER_HDR_LEN) {
538 link->stats.recvRunts++;
539 NG_FREE_DATA(m, meta);
542 if (m->m_len < ETHER_HDR_LEN && !(m = m_pullup(m, ETHER_HDR_LEN))) {
543 link->stats.memoryFailures++;
547 eh = mtod(m, struct ether_header *);
548 if ((eh->ether_shost[0] & 1) != 0) {
549 link->stats.recvInvalid++;
550 NG_FREE_DATA(m, meta);
554 /* Is link disabled due to a loopback condition? */
555 if (link->loopCount != 0) {
556 link->stats.loopDrops++;
557 NG_FREE_DATA(m, meta);
558 return (ELOOP); /* XXX is this an appropriate error? */
562 link->stats.recvPackets++;
563 link->stats.recvOctets += m->m_pkthdr.len;
564 if ((manycast = (eh->ether_dhost[0] & 1)) != 0) {
565 if (ETHER_EQUAL(eh->ether_dhost, ng_bridge_bcast_addr)) {
566 link->stats.recvBroadcasts++;
569 link->stats.recvMulticasts++;
572 /* Look up packet's source Ethernet address in hashtable */
573 if ((host = ng_bridge_get(priv, eh->ether_shost)) != NULL) {
575 /* Update time since last heard from this host */
578 /* Did host jump to a different link? */
579 if (host->linkNum != linkNum) {
582 * If the host's old link was recently established
583 * on the old link and it's already jumped to a new
584 * link, declare a loopback condition.
586 if (host->age < priv->conf.minStableAge) {
588 /* Log the problem */
589 if (priv->conf.debugLevel >= 2) {
590 struct ifnet *ifp = m->m_pkthdr.rcvif;
594 ksnprintf(suffix, sizeof(suffix),
595 " (%s)", ifp->if_xname);
598 log(LOG_WARNING, "ng_bridge: %s:"
599 " loopback detected on %s%s\n",
600 ng_bridge_nodename(node),
604 /* Mark link as linka non grata */
605 link->loopCount = priv->conf.loopTimeout;
606 link->stats.loopDetects++;
608 /* Forget all hosts on this link */
609 ng_bridge_remove_hosts(priv, linkNum);
612 link->stats.loopDrops++;
613 NG_FREE_DATA(m, meta);
614 return (ELOOP); /* XXX appropriate? */
617 /* Move host over to new link */
618 host->linkNum = linkNum;
622 if (!ng_bridge_put(priv, eh->ether_shost, linkNum)) {
623 link->stats.memoryFailures++;
624 NG_FREE_DATA(m, meta);
629 /* Run packet through ipfw processing, if enabled */
630 if (priv->conf.ipfw[linkNum] && fw_enable && ip_fw_chk_ptr != NULL) {
631 /* XXX not implemented yet */
635 * If unicast and destination host known, deliver to host's link,
636 * unless it is the same link as the packet came in on.
640 /* Determine packet destination link */
641 if ((host = ng_bridge_get(priv, eh->ether_dhost)) != NULL) {
642 struct ng_bridge_link *const destLink
643 = priv->links[host->linkNum];
645 /* If destination same as incoming link, do nothing */
646 KASSERT(destLink != NULL,
647 ("%s: link%d null", __func__, host->linkNum));
648 if (destLink == link) {
649 NG_FREE_DATA(m, meta);
653 /* Deliver packet out the destination link */
654 destLink->stats.xmitPackets++;
655 destLink->stats.xmitOctets += m->m_pkthdr.len;
656 NG_SEND_DATA(error, destLink->hook, m, meta);
660 /* Destination host is not known */
661 link->stats.recvUnknown++;
664 /* Distribute unknown, multicast, broadcast pkts to all other links */
665 for (linkNum = i = 0; i < priv->numLinks - 1; linkNum++) {
666 struct ng_bridge_link *const destLink = priv->links[linkNum];
670 /* Skip incoming link and disconnected links */
671 if (destLink == NULL || destLink == link)
674 /* Copy mbuf and meta info */
675 if (++i == priv->numLinks - 1) { /* last link */
679 m2 = m_dup(m, M_NOWAIT); /* XXX m_copypacket() */
681 link->stats.memoryFailures++;
682 NG_FREE_DATA(m, meta);
686 && (meta2 = ng_copy_meta(meta)) == NULL) {
687 link->stats.memoryFailures++;
689 NG_FREE_DATA(m, meta);
695 destLink->stats.xmitPackets++;
696 destLink->stats.xmitOctets += m->m_pkthdr.len;
698 case 0: /* unicast */
700 case 1: /* multicast */
701 destLink->stats.xmitMulticasts++;
703 case 2: /* broadcast */
704 destLink->stats.xmitBroadcasts++;
709 NG_SEND_DATA(error, destLink->hook, m2, meta2);
718 ng_bridge_rmnode(node_p node)
720 const priv_p priv = node->private;
723 * Shut down everything except the timer. There's no way to
724 * avoid another possible timeout event (it may have already
725 * been dequeued), so we can't free the node yet.
728 ng_cutlinks(node); /* frees all link and host info */
729 KASSERT(priv->numLinks == 0 && priv->numHosts == 0,
730 ("%s: numLinks=%d numHosts=%d",
731 __func__, priv->numLinks, priv->numHosts));
732 FREE(priv->tab, M_NETGRAPH);
734 /* NG_INVALID flag is now set so node will be freed at next timeout */
739 * Hook disconnection.
742 ng_bridge_disconnect(hook_p hook)
744 const priv_p priv = hook->node->private;
747 /* Get link number */
748 linkNum = LINK_NUM(hook);
749 KASSERT(linkNum >= 0 && linkNum < NG_BRIDGE_MAX_LINKS,
750 ("%s: linkNum=%u", __func__, linkNum));
752 /* Remove all hosts associated with this link */
753 ng_bridge_remove_hosts(priv, linkNum);
755 /* Free associated link information */
756 KASSERT(priv->links[linkNum] != NULL, ("%s: no link", __func__));
757 FREE(priv->links[linkNum], M_NETGRAPH);
758 priv->links[linkNum] = NULL;
761 /* If no more hooks, go away */
762 if (hook->node->numhooks == 0)
763 ng_rmnode(hook->node);
767 /******************************************************************
769 ******************************************************************/
774 * Only hashing bytes 3-6 of the Ethernet address is sufficient and fast.
776 #define HASH(addr,mask) ( (((const u_int16_t *)(addr))[0] \
777 ^ ((const u_int16_t *)(addr))[1] \
778 ^ ((const u_int16_t *)(addr))[2]) & (mask) )
781 * Find a host entry in the table.
783 static struct ng_bridge_host *
784 ng_bridge_get(priv_p priv, const u_char *addr)
786 const int bucket = HASH(addr, priv->hashMask);
787 struct ng_bridge_hent *hent;
789 SLIST_FOREACH(hent, &priv->tab[bucket], next) {
790 if (ETHER_EQUAL(hent->host.addr, addr))
791 return (&hent->host);
797 * Add a new host entry to the table. This assumes the host doesn't
798 * already exist in the table. Returns 1 on success, 0 if there
799 * was a memory allocation failure.
802 ng_bridge_put(priv_p priv, const u_char *addr, int linkNum)
804 const int bucket = HASH(addr, priv->hashMask);
805 struct ng_bridge_hent *hent;
808 /* Assert that entry does not already exist in hashtable */
809 SLIST_FOREACH(hent, &priv->tab[bucket], next) {
810 KASSERT(!ETHER_EQUAL(hent->host.addr, addr),
811 ("%s: entry %6D exists in table", __func__, addr, ":"));
815 /* Allocate and initialize new hashtable entry */
816 MALLOC(hent, struct ng_bridge_hent *,
817 sizeof(*hent), M_NETGRAPH, M_NOWAIT);
820 bcopy(addr, hent->host.addr, ETHER_ADDR_LEN);
821 hent->host.linkNum = linkNum;
822 hent->host.staleness = 0;
825 /* Add new element to hash bucket */
826 SLIST_INSERT_HEAD(&priv->tab[bucket], hent, next);
829 /* Resize table if necessary */
830 ng_bridge_rehash(priv);
835 * Resize the hash table. We try to maintain the number of buckets
836 * such that the load factor is in the range 0.25 to 1.0.
838 * If we can't get the new memory then we silently fail. This is OK
839 * because things will still work and we'll try again soon anyway.
842 ng_bridge_rehash(priv_p priv)
844 struct ng_bridge_bucket *newTab;
845 int oldBucket, newBucket;
849 /* Is table too full or too empty? */
850 if (priv->numHosts > priv->numBuckets
851 && (priv->numBuckets << 1) <= MAX_BUCKETS)
852 newNumBuckets = priv->numBuckets << 1;
853 else if (priv->numHosts < (priv->numBuckets >> 2)
854 && (priv->numBuckets >> 2) >= MIN_BUCKETS)
855 newNumBuckets = priv->numBuckets >> 2;
858 newMask = newNumBuckets - 1;
860 /* Allocate and initialize new table */
861 MALLOC(newTab, struct ng_bridge_bucket *,
862 newNumBuckets * sizeof(*newTab), M_NETGRAPH, M_NOWAIT);
865 bzero(newTab, newNumBuckets * sizeof(*newTab));
867 /* Move all entries from old table to new table */
868 for (oldBucket = 0; oldBucket < priv->numBuckets; oldBucket++) {
869 struct ng_bridge_bucket *const oldList = &priv->tab[oldBucket];
871 while (!SLIST_EMPTY(oldList)) {
872 struct ng_bridge_hent *const hent
873 = SLIST_FIRST(oldList);
875 SLIST_REMOVE_HEAD(oldList, next);
876 newBucket = HASH(hent->host.addr, newMask);
877 SLIST_INSERT_HEAD(&newTab[newBucket], hent, next);
881 /* Replace old table with new one */
882 if (priv->conf.debugLevel >= 3) {
883 log(LOG_INFO, "ng_bridge: %s: table size %d -> %d\n",
884 ng_bridge_nodename(priv->node),
885 priv->numBuckets, newNumBuckets);
887 FREE(priv->tab, M_NETGRAPH);
888 priv->numBuckets = newNumBuckets;
889 priv->hashMask = newMask;
894 /******************************************************************
896 ******************************************************************/
899 * Remove all hosts associated with a specific link from the hashtable.
900 * If linkNum == -1, then remove all hosts in the table.
903 ng_bridge_remove_hosts(priv_p priv, int linkNum)
907 for (bucket = 0; bucket < priv->numBuckets; bucket++) {
908 struct ng_bridge_hent **hptr = &SLIST_FIRST(&priv->tab[bucket]);
910 while (*hptr != NULL) {
911 struct ng_bridge_hent *const hent = *hptr;
913 if (linkNum == -1 || hent->host.linkNum == linkNum) {
914 *hptr = SLIST_NEXT(hent, next);
915 FREE(hent, M_NETGRAPH);
918 hptr = &SLIST_NEXT(hent, next);
924 * Handle our once-per-second timeout event. We do two things:
925 * we decrement link->loopCount for those links being muted due to
926 * a detected loopback condition, and we remove any hosts from
927 * the hashtable whom we haven't heard from in a long while.
929 * If the node has the NG_INVALID flag set, our job is to kill it.
932 ng_bridge_timeout(void *arg)
934 const node_p node = arg;
935 const priv_p priv = node->private;
940 /* If node was shut down, this is the final lingering timeout */
942 if ((node->flags & NG_INVALID) != 0) {
943 FREE(priv, M_NETGRAPH);
944 node->private = NULL;
950 /* Register a new timeout, keeping the existing node reference */
951 callout_reset(&priv->timer, hz, ng_bridge_timeout, node);
953 /* Update host time counters and remove stale entries */
954 for (bucket = 0; bucket < priv->numBuckets; bucket++) {
955 struct ng_bridge_hent **hptr = &SLIST_FIRST(&priv->tab[bucket]);
957 while (*hptr != NULL) {
958 struct ng_bridge_hent *const hent = *hptr;
960 /* Make sure host's link really exists */
961 KASSERT(priv->links[hent->host.linkNum] != NULL,
962 ("%s: host %6D on nonexistent link %d\n",
963 __func__, hent->host.addr, ":",
964 hent->host.linkNum));
966 /* Remove hosts we haven't heard from in a while */
967 if (++hent->host.staleness >= priv->conf.maxStaleness) {
968 *hptr = SLIST_NEXT(hent, next);
969 FREE(hent, M_NETGRAPH);
972 if (hent->host.age < 0xffff)
974 hptr = &SLIST_NEXT(hent, next);
979 KASSERT(priv->numHosts == counter,
980 ("%s: hosts: %d != %d", __func__, priv->numHosts, counter));
982 /* Decrease table size if necessary */
983 ng_bridge_rehash(priv);
985 /* Decrease loop counter on muted looped back links */
986 for (counter = linkNum = 0; linkNum < NG_BRIDGE_MAX_LINKS; linkNum++) {
987 struct ng_bridge_link *const link = priv->links[linkNum];
990 if (link->loopCount != 0) {
992 if (link->loopCount == 0
993 && priv->conf.debugLevel >= 2) {
994 log(LOG_INFO, "ng_bridge: %s:"
995 " restoring looped back link%d\n",
996 ng_bridge_nodename(node), linkNum);
1002 KASSERT(priv->numLinks == counter,
1003 ("%s: links: %d != %d", __func__, priv->numLinks, counter));
1010 * Return node's "name", even if it doesn't have one.
1013 ng_bridge_nodename(node_p node)
1015 static char name[NG_NODESIZ];
1017 if (node->name != NULL)
1018 ksnprintf(name, sizeof(name), "%s", node->name);
1020 ksnprintf(name, sizeof(name), "[%x]", ng_node2ID(node));