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11 * without modifications are expressly permitted by Whistle Communications;
12 * provided, however, that:
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35 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
38 * Author: Archie Cobbs <archie@freebsd.org>
40 * $FreeBSD: src/sys/netgraph/ng_bridge.c,v 1.31 2005/02/09 15:14:44 ru 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>
72 #include <net/ethernet.h>
74 #include <netinet/in.h>
75 #include <net/ipfw/ip_fw.h>
77 #include <netgraph7/ng_message.h>
78 #include <netgraph7/netgraph.h>
79 #include <netgraph7/ng_parse.h>
80 #include "ng_bridge.h"
82 #ifdef NG_SEPARATE_MALLOC
83 MALLOC_DEFINE(M_NETGRAPH_BRIDGE, "netgraph_bridge", "netgraph bridge node ");
85 #define M_NETGRAPH_BRIDGE M_NETGRAPH
88 /* Per-link private data */
89 struct ng_bridge_link {
90 hook_p hook; /* netgraph hook */
91 u_int16_t loopCount; /* loop ignore timer */
92 struct ng_bridge_link_stats stats; /* link stats */
95 /* Per-node private data */
96 struct ng_bridge_private {
97 struct ng_bridge_bucket *tab; /* hash table bucket array */
98 struct ng_bridge_link *links[NG_BRIDGE_MAX_LINKS];
99 struct ng_bridge_config conf; /* node configuration */
100 node_p node; /* netgraph node */
101 u_int numHosts; /* num entries in table */
102 u_int numBuckets; /* num buckets in table */
103 u_int hashMask; /* numBuckets - 1 */
104 int numLinks; /* num connected links */
105 struct callout timer; /* one second periodic timer */
107 typedef struct ng_bridge_private *priv_p;
109 /* Information about a host, stored in a hash table entry */
110 struct ng_bridge_hent {
111 struct ng_bridge_host host; /* actual host info */
112 SLIST_ENTRY(ng_bridge_hent) next; /* next entry in bucket */
115 /* Hash table bucket declaration */
116 SLIST_HEAD(ng_bridge_bucket, ng_bridge_hent);
118 /* Netgraph node methods */
119 static ng_constructor_t ng_bridge_constructor;
120 static ng_rcvmsg_t ng_bridge_rcvmsg;
121 static ng_shutdown_t ng_bridge_shutdown;
122 static ng_newhook_t ng_bridge_newhook;
123 static ng_rcvdata_t ng_bridge_rcvdata;
124 static ng_disconnect_t ng_bridge_disconnect;
126 /* Other internal functions */
127 static struct ng_bridge_host *ng_bridge_get(priv_p priv, const u_char *addr);
128 static int ng_bridge_put(priv_p priv, const u_char *addr, int linkNum);
129 static void ng_bridge_rehash(priv_p priv);
130 static void ng_bridge_remove_hosts(priv_p priv, int linkNum);
131 static void ng_bridge_timeout(node_p node, hook_p hook, void *arg1, int arg2);
132 static const char *ng_bridge_nodename(node_p node);
134 /* Ethernet broadcast */
135 static const u_char ng_bridge_bcast_addr[ETHER_ADDR_LEN] =
136 { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
138 /* Store each hook's link number in the private field */
139 #define LINK_NUM(hook) (*(u_int16_t *)(&(hook)->private))
141 /* Compare Ethernet addresses using 32 and 16 bit words instead of bytewise */
142 #define ETHER_EQUAL(a,b) (((const u_int32_t *)(a))[0] \
143 == ((const u_int32_t *)(b))[0] \
144 && ((const u_int16_t *)(a))[2] \
145 == ((const u_int16_t *)(b))[2])
147 /* Minimum and maximum number of hash buckets. Must be a power of two. */
148 #define MIN_BUCKETS (1 << 5) /* 32 */
149 #define MAX_BUCKETS (1 << 14) /* 16384 */
151 /* Configuration default values */
152 #define DEFAULT_LOOP_TIMEOUT 60
153 #define DEFAULT_MAX_STALENESS (15 * 60) /* same as ARP timeout */
154 #define DEFAULT_MIN_STABLE_AGE 1
156 /******************************************************************
158 ******************************************************************/
161 * How to determine the length of the table returned by NGM_BRIDGE_GET_TABLE
164 ng_bridge_getTableLength(const struct ng_parse_type *type,
165 const u_char *start, const u_char *buf)
167 const struct ng_bridge_host_ary *const hary
168 = (const struct ng_bridge_host_ary *)(buf - sizeof(u_int32_t));
170 return hary->numHosts;
173 /* Parse type for struct ng_bridge_host_ary */
174 static const struct ng_parse_struct_field ng_bridge_host_type_fields[]
175 = NG_BRIDGE_HOST_TYPE_INFO(&ng_parse_enaddr_type);
176 static const struct ng_parse_type ng_bridge_host_type = {
177 &ng_parse_struct_type,
178 &ng_bridge_host_type_fields
180 static const struct ng_parse_array_info ng_bridge_hary_type_info = {
181 &ng_bridge_host_type,
182 ng_bridge_getTableLength
184 static const struct ng_parse_type ng_bridge_hary_type = {
185 &ng_parse_array_type,
186 &ng_bridge_hary_type_info
188 static const struct ng_parse_struct_field ng_bridge_host_ary_type_fields[]
189 = NG_BRIDGE_HOST_ARY_TYPE_INFO(&ng_bridge_hary_type);
190 static const struct ng_parse_type ng_bridge_host_ary_type = {
191 &ng_parse_struct_type,
192 &ng_bridge_host_ary_type_fields
195 /* Parse type for struct ng_bridge_config */
196 static const struct ng_parse_fixedarray_info ng_bridge_ipfwary_type_info = {
197 &ng_parse_uint8_type,
200 static const struct ng_parse_type ng_bridge_ipfwary_type = {
201 &ng_parse_fixedarray_type,
202 &ng_bridge_ipfwary_type_info
204 static const struct ng_parse_struct_field ng_bridge_config_type_fields[]
205 = NG_BRIDGE_CONFIG_TYPE_INFO(&ng_bridge_ipfwary_type);
206 static const struct ng_parse_type ng_bridge_config_type = {
207 &ng_parse_struct_type,
208 &ng_bridge_config_type_fields
211 /* Parse type for struct ng_bridge_link_stat */
212 static const struct ng_parse_struct_field ng_bridge_stats_type_fields[]
213 = NG_BRIDGE_STATS_TYPE_INFO;
214 static const struct ng_parse_type ng_bridge_stats_type = {
215 &ng_parse_struct_type,
216 &ng_bridge_stats_type_fields
219 /* List of commands and how to convert arguments to/from ASCII */
220 static const struct ng_cmdlist ng_bridge_cmdlist[] = {
223 NGM_BRIDGE_SET_CONFIG,
225 &ng_bridge_config_type,
230 NGM_BRIDGE_GET_CONFIG,
233 &ng_bridge_config_type
244 NGM_BRIDGE_GET_STATS,
246 &ng_parse_uint32_type,
247 &ng_bridge_stats_type
251 NGM_BRIDGE_CLR_STATS,
253 &ng_parse_uint32_type,
258 NGM_BRIDGE_GETCLR_STATS,
260 &ng_parse_uint32_type,
261 &ng_bridge_stats_type
265 NGM_BRIDGE_GET_TABLE,
268 &ng_bridge_host_ary_type
273 /* Node type descriptor */
274 static struct ng_type ng_bridge_typestruct = {
275 .version = NG_ABI_VERSION,
276 .name = NG_BRIDGE_NODE_TYPE,
277 .constructor = ng_bridge_constructor,
278 .rcvmsg = ng_bridge_rcvmsg,
279 .shutdown = ng_bridge_shutdown,
280 .newhook = ng_bridge_newhook,
281 .rcvdata = ng_bridge_rcvdata,
282 .disconnect = ng_bridge_disconnect,
283 .cmdlist = ng_bridge_cmdlist,
285 NETGRAPH_INIT(bridge, &ng_bridge_typestruct);
287 /******************************************************************
288 NETGRAPH NODE METHODS
289 ******************************************************************/
295 ng_bridge_constructor(node_p node)
299 /* Allocate and initialize private info */
300 priv = kmalloc(sizeof(*priv), M_NETGRAPH_BRIDGE,
301 M_WAITOK | M_NULLOK | M_ZERO);
304 ng_callout_init(&priv->timer);
306 /* Allocate and initialize hash table, etc. */
307 priv->tab = kmalloc(MIN_BUCKETS * sizeof(*priv->tab),
308 M_NETGRAPH_BRIDGE, M_WAITOK | M_NULLOK | M_ZERO);
309 if (priv->tab == NULL) {
310 kfree(priv, M_NETGRAPH_BRIDGE);
313 priv->numBuckets = MIN_BUCKETS;
314 priv->hashMask = MIN_BUCKETS - 1;
315 priv->conf.debugLevel = 1;
316 priv->conf.loopTimeout = DEFAULT_LOOP_TIMEOUT;
317 priv->conf.maxStaleness = DEFAULT_MAX_STALENESS;
318 priv->conf.minStableAge = DEFAULT_MIN_STABLE_AGE;
321 * This node has all kinds of stuff that could be screwed by SMP.
322 * Until it gets it's own internal protection, we go through in
323 * single file. This could hurt a machine bridging beteen two
324 * GB ethernets so it should be fixed.
325 * When it's fixed the process SHOULD NOT SLEEP, spinlocks please!
328 NG_NODE_FORCE_WRITER(node);
329 NG_NODE_SET_PRIVATE(node, priv);
332 /* Start timer; timer is always running while node is alive */
333 ng_callout(&priv->timer, node, NULL, hz, ng_bridge_timeout, NULL, 0);
340 * Method for attaching a new hook
343 ng_bridge_newhook(node_p node, hook_p hook, const char *name)
345 const priv_p priv = NG_NODE_PRIVATE(node);
347 /* Check for a link hook */
348 if (strncmp(name, NG_BRIDGE_HOOK_LINK_PREFIX,
349 strlen(NG_BRIDGE_HOOK_LINK_PREFIX)) == 0) {
354 cp = name + strlen(NG_BRIDGE_HOOK_LINK_PREFIX);
355 if (!isdigit(*cp) || (cp[0] == '0' && cp[1] != '\0'))
357 linkNum = strtoul(cp, &eptr, 10);
358 if (*eptr != '\0' || linkNum >= NG_BRIDGE_MAX_LINKS)
360 if (priv->links[linkNum] != NULL)
362 priv->links[linkNum] = kmalloc(sizeof(*priv->links[linkNum]),
364 M_WAITOK | M_NULLOK | M_ZERO);
365 if (priv->links[linkNum] == NULL)
367 priv->links[linkNum]->hook = hook;
368 NG_HOOK_SET_PRIVATE(hook, (void *)linkNum);
373 /* Unknown hook name */
378 * Receive a control message
381 ng_bridge_rcvmsg(node_p node, item_p item, hook_p lasthook)
383 const priv_p priv = NG_NODE_PRIVATE(node);
384 struct ng_mesg *resp = NULL;
388 NGI_GET_MSG(item, msg);
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_WAITOK | M_NULLOK);
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_WAITOK | M_NULLOK);
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_WAITOK | M_NULLOK);
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;
507 NG_RESPOND_MSG(error, node, item, resp);
513 * Receive data on a hook
516 ng_bridge_rcvdata(hook_p hook, item_p item)
518 const node_p node = NG_HOOK_NODE(hook);
519 const priv_p priv = NG_NODE_PRIVATE(node);
520 struct ng_bridge_host *host;
521 struct ng_bridge_link *link;
522 struct ether_header *eh;
523 int error = 0, linkNum, linksSeen;
526 struct ng_bridge_link *firstLink;
529 /* Get link number */
530 linkNum = (intptr_t)NG_HOOK_PRIVATE(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++;
543 if (m->m_len < ETHER_HDR_LEN && !(m = m_pullup(m, ETHER_HDR_LEN))) {
544 link->stats.memoryFailures++;
548 eh = mtod(m, struct ether_header *);
549 if ((eh->ether_shost[0] & 1) != 0) {
550 link->stats.recvInvalid++;
556 /* Is link disabled due to a loopback condition? */
557 if (link->loopCount != 0) {
558 link->stats.loopDrops++;
561 return (ELOOP); /* XXX is this an appropriate error? */
565 link->stats.recvPackets++;
566 link->stats.recvOctets += m->m_pkthdr.len;
567 if ((manycast = (eh->ether_dhost[0] & 1)) != 0) {
568 if (ETHER_EQUAL(eh->ether_dhost, ng_bridge_bcast_addr)) {
569 link->stats.recvBroadcasts++;
572 link->stats.recvMulticasts++;
575 /* Look up packet's source Ethernet address in hashtable */
576 if ((host = ng_bridge_get(priv, eh->ether_shost)) != NULL) {
578 /* Update time since last heard from this host */
581 /* Did host jump to a different link? */
582 if (host->linkNum != linkNum) {
585 * If the host's old link was recently established
586 * on the old link and it's already jumped to a new
587 * link, declare a loopback condition.
589 if (host->age < priv->conf.minStableAge) {
591 /* Log the problem */
592 if (priv->conf.debugLevel >= 2) {
593 struct ifnet *ifp = m->m_pkthdr.rcvif;
597 ksnprintf(suffix, sizeof(suffix),
598 " (%s)", ifp->if_xname);
601 log(LOG_WARNING, "ng_bridge: %s:"
602 " loopback detected on %s%s\n",
603 ng_bridge_nodename(node),
604 NG_HOOK_NAME(hook), suffix);
607 /* Mark link as linka non grata */
608 link->loopCount = priv->conf.loopTimeout;
609 link->stats.loopDetects++;
611 /* Forget all hosts on this link */
612 ng_bridge_remove_hosts(priv, linkNum);
615 link->stats.loopDrops++;
618 return (ELOOP); /* XXX appropriate? */
621 /* Move host over to new link */
622 host->linkNum = linkNum;
626 if (!ng_bridge_put(priv, eh->ether_shost, linkNum)) {
627 link->stats.memoryFailures++;
634 /* Run packet through ipfw processing, if enabled */
636 if (priv->conf.ipfw[linkNum] && fw_enable && ip_fw_chk_ptr != NULL) {
637 /* XXX not implemented yet */
642 * If unicast and destination host known, deliver to host's link,
643 * unless it is the same link as the packet came in on.
647 /* Determine packet destination link */
648 if ((host = ng_bridge_get(priv, eh->ether_dhost)) != NULL) {
649 struct ng_bridge_link *const destLink
650 = priv->links[host->linkNum];
652 /* If destination same as incoming link, do nothing */
653 KASSERT(destLink != NULL,
654 ("%s: link%d null", __func__, host->linkNum));
655 if (destLink == link) {
661 /* Deliver packet out the destination link */
662 destLink->stats.xmitPackets++;
663 destLink->stats.xmitOctets += m->m_pkthdr.len;
664 NG_FWD_NEW_DATA(error, item, destLink->hook, m);
668 /* Destination host is not known */
669 link->stats.recvUnknown++;
672 /* Distribute unknown, multicast, broadcast pkts to all other links */
674 for (linkNum = linksSeen = 0; linksSeen <= priv->numLinks; linkNum++) {
675 struct ng_bridge_link *destLink;
676 struct mbuf *m2 = NULL;
679 * If we have checked all the links then now
680 * send the original on its reserved link
682 if (linksSeen == priv->numLinks) {
683 /* If we never saw a good link, leave. */
684 if (firstLink == NULL) {
689 destLink = firstLink;
691 destLink = priv->links[linkNum];
692 if (destLink != NULL)
694 /* Skip incoming link and disconnected links */
695 if (destLink == NULL || destLink == link) {
698 if (firstLink == NULL) {
700 * This is the first usable link we have found.
701 * Reserve it for the originals.
702 * If we never find another we save a copy.
704 firstLink = destLink;
709 * It's usable link but not the reserved (first) one.
710 * Copy mbuf info for sending.
712 m2 = m_dup(m, MB_DONTWAIT); /* XXX m_copypacket() */
714 link->stats.memoryFailures++;
722 destLink->stats.xmitPackets++;
723 destLink->stats.xmitOctets += m->m_pkthdr.len;
725 case 0: /* unicast */
727 case 1: /* multicast */
728 destLink->stats.xmitMulticasts++;
730 case 2: /* broadcast */
731 destLink->stats.xmitBroadcasts++;
736 if (destLink == firstLink) {
738 * If we've sent all the others, send the original
739 * on the first link we found.
741 NG_FWD_NEW_DATA(error, item, destLink->hook, m);
742 break; /* always done last - not really needed. */
744 NG_SEND_DATA_ONLY(error, destLink->hook, m2);
754 ng_bridge_shutdown(node_p node)
756 const priv_p priv = NG_NODE_PRIVATE(node);
759 * Shut down everything including the timer. Even if the
760 * callout has already been dequeued and is about to be
761 * run, ng_bridge_timeout() won't be fired as the node
762 * is already marked NGF_INVALID, so we're safe to free
765 KASSERT(priv->numLinks == 0 && priv->numHosts == 0,
766 ("%s: numLinks=%d numHosts=%d",
767 __func__, priv->numLinks, priv->numHosts));
768 ng_uncallout(&priv->timer, node);
769 NG_NODE_SET_PRIVATE(node, NULL);
771 kfree(priv->tab, M_NETGRAPH_BRIDGE);
772 kfree(priv, M_NETGRAPH_BRIDGE);
777 * Hook disconnection.
780 ng_bridge_disconnect(hook_p hook)
782 const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
785 /* Get link number */
786 linkNum = (intptr_t)NG_HOOK_PRIVATE(hook);
787 KASSERT(linkNum >= 0 && linkNum < NG_BRIDGE_MAX_LINKS,
788 ("%s: linkNum=%u", __func__, linkNum));
790 /* Remove all hosts associated with this link */
791 ng_bridge_remove_hosts(priv, linkNum);
793 /* Free associated link information */
794 KASSERT(priv->links[linkNum] != NULL, ("%s: no link", __func__));
795 kfree(priv->links[linkNum], M_NETGRAPH_BRIDGE);
796 priv->links[linkNum] = NULL;
799 /* If no more hooks, go away */
800 if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0)
801 && (NG_NODE_IS_VALID(NG_HOOK_NODE(hook)))) {
802 ng_rmnode_self(NG_HOOK_NODE(hook));
807 /******************************************************************
809 ******************************************************************/
814 #define HASH(addr,mask) ( (((const u_int16_t *)(addr))[0] \
815 ^ ((const u_int16_t *)(addr))[1] \
816 ^ ((const u_int16_t *)(addr))[2]) & (mask) )
819 * Find a host entry in the table.
821 static struct ng_bridge_host *
822 ng_bridge_get(priv_p priv, const u_char *addr)
824 const int bucket = HASH(addr, priv->hashMask);
825 struct ng_bridge_hent *hent;
827 SLIST_FOREACH(hent, &priv->tab[bucket], next) {
828 if (ETHER_EQUAL(hent->host.addr, addr))
829 return (&hent->host);
835 * Add a new host entry to the table. This assumes the host doesn't
836 * already exist in the table. Returns 1 on success, 0 if there
837 * was a memory allocation failure.
840 ng_bridge_put(priv_p priv, const u_char *addr, int linkNum)
842 const int bucket = HASH(addr, priv->hashMask);
843 struct ng_bridge_hent *hent;
844 char ethstr[ETHER_ADDRSTRLEN + 1] __debugvar;
847 /* Assert that entry does not already exist in hashtable */
848 SLIST_FOREACH(hent, &priv->tab[bucket], next) {
849 KASSERT(!ETHER_EQUAL(hent->host.addr, addr),
850 ("%s: entry %s exists in table", __func__, kether_ntoa(addr, ethstr)));
854 /* Allocate and initialize new hashtable entry */
855 hent = kmalloc(sizeof(*hent), M_NETGRAPH_BRIDGE, M_WAITOK | M_NULLOK);
858 bcopy(addr, hent->host.addr, ETHER_ADDR_LEN);
859 hent->host.linkNum = linkNum;
860 hent->host.staleness = 0;
863 /* Add new element to hash bucket */
864 SLIST_INSERT_HEAD(&priv->tab[bucket], hent, next);
867 /* Resize table if necessary */
868 ng_bridge_rehash(priv);
873 * Resize the hash table. We try to maintain the number of buckets
874 * such that the load factor is in the range 0.25 to 1.0.
876 * If we can't get the new memory then we silently fail. This is OK
877 * because things will still work and we'll try again soon anyway.
880 ng_bridge_rehash(priv_p priv)
882 struct ng_bridge_bucket *newTab;
883 int oldBucket, newBucket;
887 /* Is table too full or too empty? */
888 if (priv->numHosts > priv->numBuckets
889 && (priv->numBuckets << 1) <= MAX_BUCKETS)
890 newNumBuckets = priv->numBuckets << 1;
891 else if (priv->numHosts < (priv->numBuckets >> 2)
892 && (priv->numBuckets >> 2) >= MIN_BUCKETS)
893 newNumBuckets = priv->numBuckets >> 2;
896 newMask = newNumBuckets - 1;
898 /* Allocate and initialize new table */
899 newTab = kmalloc(newNumBuckets * sizeof(*newTab), M_NETGRAPH_BRIDGE,
904 /* Move all entries from old table to new table */
905 for (oldBucket = 0; oldBucket < priv->numBuckets; oldBucket++) {
906 struct ng_bridge_bucket *const oldList = &priv->tab[oldBucket];
908 while (!SLIST_EMPTY(oldList)) {
909 struct ng_bridge_hent *const hent
910 = SLIST_FIRST(oldList);
912 SLIST_REMOVE_HEAD(oldList, next);
913 newBucket = HASH(hent->host.addr, newMask);
914 SLIST_INSERT_HEAD(&newTab[newBucket], hent, next);
918 /* Replace old table with new one */
919 if (priv->conf.debugLevel >= 3) {
920 log(LOG_INFO, "ng_bridge: %s: table size %d -> %d\n",
921 ng_bridge_nodename(priv->node),
922 priv->numBuckets, newNumBuckets);
924 kfree(priv->tab, M_NETGRAPH_BRIDGE);
925 priv->numBuckets = newNumBuckets;
926 priv->hashMask = newMask;
931 /******************************************************************
933 ******************************************************************/
936 * Remove all hosts associated with a specific link from the hashtable.
937 * If linkNum == -1, then remove all hosts in the table.
940 ng_bridge_remove_hosts(priv_p priv, int linkNum)
944 for (bucket = 0; bucket < priv->numBuckets; bucket++) {
945 struct ng_bridge_hent **hptr = &SLIST_FIRST(&priv->tab[bucket]);
947 while (*hptr != NULL) {
948 struct ng_bridge_hent *const hent = *hptr;
950 if (linkNum == -1 || hent->host.linkNum == linkNum) {
951 *hptr = SLIST_NEXT(hent, next);
952 kfree(hent, M_NETGRAPH_BRIDGE);
955 hptr = &SLIST_NEXT(hent, next);
961 * Handle our once-per-second timeout event. We do two things:
962 * we decrement link->loopCount for those links being muted due to
963 * a detected loopback condition, and we remove any hosts from
964 * the hashtable whom we haven't heard from in a long while.
967 ng_bridge_timeout(node_p node, hook_p hook, void *arg1, int arg2)
969 const priv_p priv = NG_NODE_PRIVATE(node);
973 char ethstr[ETHER_ADDRSTRLEN + 1] __debugvar;
975 /* Update host time counters and remove stale entries */
976 for (bucket = 0; bucket < priv->numBuckets; bucket++) {
977 struct ng_bridge_hent **hptr = &SLIST_FIRST(&priv->tab[bucket]);
979 while (*hptr != NULL) {
980 struct ng_bridge_hent *const hent = *hptr;
982 /* Make sure host's link really exists */
983 KASSERT(priv->links[hent->host.linkNum] != NULL,
984 ("%s: host %s on nonexistent link %d",
985 __func__, kether_ntoa(hent->host.addr, ethstr),
986 hent->host.linkNum));
988 /* Remove hosts we haven't heard from in a while */
989 if (++hent->host.staleness >= priv->conf.maxStaleness) {
990 *hptr = SLIST_NEXT(hent, next);
991 kfree(hent, M_NETGRAPH_BRIDGE);
994 if (hent->host.age < 0xffff)
996 hptr = &SLIST_NEXT(hent, next);
1001 KASSERT(priv->numHosts == counter,
1002 ("%s: hosts: %d != %d", __func__, priv->numHosts, counter));
1004 /* Decrease table size if necessary */
1005 ng_bridge_rehash(priv);
1007 /* Decrease loop counter on muted looped back links */
1008 for (counter = linkNum = 0; linkNum < NG_BRIDGE_MAX_LINKS; linkNum++) {
1009 struct ng_bridge_link *const link = priv->links[linkNum];
1012 if (link->loopCount != 0) {
1014 if (link->loopCount == 0
1015 && priv->conf.debugLevel >= 2) {
1016 log(LOG_INFO, "ng_bridge: %s:"
1017 " restoring looped back link%d\n",
1018 ng_bridge_nodename(node), linkNum);
1024 KASSERT(priv->numLinks == counter,
1025 ("%s: links: %d != %d", __func__, priv->numLinks, counter));
1027 /* Register a new timeout, keeping the existing node reference */
1028 ng_callout(&priv->timer, node, NULL, hz, ng_bridge_timeout, NULL, 0);
1032 * Return node's "name", even if it doesn't have one.
1035 ng_bridge_nodename(node_p node)
1037 static char name[NG_NODESIZ];
1039 if (NG_NODE_NAME(node) != NULL)
1040 ksnprintf(name, sizeof(name), "%s", NG_NODE_NAME(node));
1042 ksnprintf(name, sizeof(name), "[%x]", ng_node2ID(node));