/*- * Copyright (c) 2000 Whistle Communications, Inc. * All rights reserved. * * Subject to the following obligations and disclaimer of warranty, use and * redistribution of this software, in source or object code forms, with or * without modifications are expressly permitted by Whistle Communications; * provided, however, that: * 1. Any and all reproductions of the source or object code must include the * copyright notice above and the following disclaimer of warranties; and * 2. No rights are granted, in any manner or form, to use Whistle * Communications, Inc. trademarks, including the mark "WHISTLE * COMMUNICATIONS" on advertising, endorsements, or otherwise except as * such appears in the above copyright notice or in the software. * * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE, * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE. * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY * OF SUCH DAMAGE. * * Author: Archie Cobbs * * $FreeBSD$ */ /* * ng_bridge(4) netgraph node type * * The node performs standard intelligent Ethernet bridging over * each of its connected hooks, or links. A simple loop detection * algorithm is included which disables a link for priv->conf.loopTimeout * seconds when a host is seen to have jumped from one link to * another within priv->conf.minStableAge seconds. * * We keep a hashtable that maps Ethernet addresses to host info, * which is contained in struct ng_bridge_host's. These structures * tell us on which link the host may be found. A host's entry will * expire after priv->conf.maxStaleness seconds. * * This node is optimzed for stable networks, where machines jump * from one port to the other only rarely. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #if 0 /* not used yet */ #include #endif #include #include #include #include #ifdef NG_SEPARATE_MALLOC static MALLOC_DEFINE(M_NETGRAPH_BRIDGE, "netgraph_bridge", "netgraph bridge node"); #else #define M_NETGRAPH_BRIDGE M_NETGRAPH #endif /* Counter based stats */ struct ng_bridge_link_kernel_stats { counter_u64_t recvOctets; /* total octets rec'd on link */ counter_u64_t recvPackets; /* total pkts rec'd on link */ counter_u64_t recvMulticasts; /* multicast pkts rec'd on link */ counter_u64_t recvBroadcasts; /* broadcast pkts rec'd on link */ counter_u64_t recvUnknown; /* pkts rec'd with unknown dest addr */ counter_u64_t recvRunts; /* pkts rec'd less than 14 bytes */ counter_u64_t recvInvalid; /* pkts rec'd with bogus source addr */ counter_u64_t xmitOctets; /* total octets xmit'd on link */ counter_u64_t xmitPackets; /* total pkts xmit'd on link */ counter_u64_t xmitMulticasts; /* multicast pkts xmit'd on link */ counter_u64_t xmitBroadcasts; /* broadcast pkts xmit'd on link */ counter_u64_t loopDrops; /* pkts dropped due to loopback */ u_int64_t loopDetects; /* number of loop detections */ counter_u64_t memoryFailures; /* times couldn't get mem or mbuf */ }; /* Per-link private data */ struct ng_bridge_link { hook_p hook; /* netgraph hook */ u_int16_t loopCount; /* loop ignore timer */ unsigned int learnMac : 1, /* autolearn macs */ sendUnknown : 1;/* send unknown macs out */ struct ng_bridge_link_kernel_stats stats; /* link stats */ }; typedef struct ng_bridge_link const *link_cp; /* read only access */ /* Per-node private data */ struct ng_bridge_private { struct ng_bridge_bucket *tab; /* hash table bucket array */ struct ng_bridge_config conf; /* node configuration */ node_p node; /* netgraph node */ u_int numHosts; /* num entries in table */ u_int numBuckets; /* num buckets in table */ u_int hashMask; /* numBuckets - 1 */ int numLinks; /* num connected links */ unsigned int persistent : 1, /* can exist w/o hooks */ sendUnknown : 1;/* links receive unknowns by default */ struct callout timer; /* one second periodic timer */ }; typedef struct ng_bridge_private *priv_p; typedef struct ng_bridge_private const *priv_cp; /* read only access */ /* Information about a host, stored in a hash table entry */ struct ng_bridge_host { u_char addr[6]; /* ethernet address */ link_p link; /* link where addr can be found */ u_int16_t age; /* seconds ago entry was created */ u_int16_t staleness; /* seconds ago host last heard from */ SLIST_ENTRY(ng_bridge_host) next; /* next entry in bucket */ }; /* Hash table bucket declaration */ SLIST_HEAD(ng_bridge_bucket, ng_bridge_host); /* Netgraph node methods */ static ng_constructor_t ng_bridge_constructor; static ng_rcvmsg_t ng_bridge_rcvmsg; static ng_shutdown_t ng_bridge_shutdown; static ng_newhook_t ng_bridge_newhook; static ng_rcvdata_t ng_bridge_rcvdata; static ng_disconnect_t ng_bridge_disconnect; /* Other internal functions */ static void ng_bridge_free_link(link_p link); static struct ng_bridge_host *ng_bridge_get(priv_cp priv, const u_char *addr); static int ng_bridge_put(priv_p priv, const u_char *addr, link_p link); static void ng_bridge_rehash(priv_p priv); static void ng_bridge_remove_hosts(priv_p priv, link_p link); static void ng_bridge_timeout(node_p node, hook_p hook, void *arg1, int arg2); static const char *ng_bridge_nodename(node_cp node); /* Ethernet broadcast */ static const u_char ng_bridge_bcast_addr[ETHER_ADDR_LEN] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; /* Compare Ethernet addresses using 32 and 16 bit words instead of bytewise */ #define ETHER_EQUAL(a,b) (((const u_int32_t *)(a))[0] \ == ((const u_int32_t *)(b))[0] \ && ((const u_int16_t *)(a))[2] \ == ((const u_int16_t *)(b))[2]) /* Minimum and maximum number of hash buckets. Must be a power of two. */ #define MIN_BUCKETS (1 << 5) /* 32 */ #define MAX_BUCKETS (1 << 14) /* 16384 */ /* Configuration default values */ #define DEFAULT_LOOP_TIMEOUT 60 #define DEFAULT_MAX_STALENESS (15 * 60) /* same as ARP timeout */ #define DEFAULT_MIN_STABLE_AGE 1 /****************************************************************** NETGRAPH PARSE TYPES ******************************************************************/ /* * How to determine the length of the table returned by NGM_BRIDGE_GET_TABLE */ static int ng_bridge_getTableLength(const struct ng_parse_type *type, const u_char *start, const u_char *buf) { const struct ng_bridge_host_ary *const hary = (const struct ng_bridge_host_ary *)(buf - sizeof(u_int32_t)); return hary->numHosts; } /* Parse type for struct ng_bridge_host_ary */ static const struct ng_parse_struct_field ng_bridge_host_type_fields[] = NG_BRIDGE_HOST_TYPE_INFO(&ng_parse_enaddr_type); static const struct ng_parse_type ng_bridge_host_type = { &ng_parse_struct_type, &ng_bridge_host_type_fields }; static const struct ng_parse_array_info ng_bridge_hary_type_info = { &ng_bridge_host_type, ng_bridge_getTableLength }; static const struct ng_parse_type ng_bridge_hary_type = { &ng_parse_array_type, &ng_bridge_hary_type_info }; static const struct ng_parse_struct_field ng_bridge_host_ary_type_fields[] = NG_BRIDGE_HOST_ARY_TYPE_INFO(&ng_bridge_hary_type); static const struct ng_parse_type ng_bridge_host_ary_type = { &ng_parse_struct_type, &ng_bridge_host_ary_type_fields }; /* Parse type for struct ng_bridge_config */ static const struct ng_parse_struct_field ng_bridge_config_type_fields[] = NG_BRIDGE_CONFIG_TYPE_INFO; static const struct ng_parse_type ng_bridge_config_type = { &ng_parse_struct_type, &ng_bridge_config_type_fields }; /* Parse type for struct ng_bridge_link_stat */ static const struct ng_parse_struct_field ng_bridge_stats_type_fields[] = NG_BRIDGE_STATS_TYPE_INFO; static const struct ng_parse_type ng_bridge_stats_type = { &ng_parse_struct_type, &ng_bridge_stats_type_fields }; /* Parse type for struct ng_bridge_move_host */ static const struct ng_parse_struct_field ng_bridge_move_host_type_fields[] = NG_BRIDGE_MOVE_HOST_TYPE_INFO(&ng_parse_enaddr_type); static const struct ng_parse_type ng_bridge_move_host_type = { &ng_parse_struct_type, &ng_bridge_move_host_type_fields }; /* List of commands and how to convert arguments to/from ASCII */ static const struct ng_cmdlist ng_bridge_cmdlist[] = { { NGM_BRIDGE_COOKIE, NGM_BRIDGE_SET_CONFIG, "setconfig", &ng_bridge_config_type, NULL }, { NGM_BRIDGE_COOKIE, NGM_BRIDGE_GET_CONFIG, "getconfig", NULL, &ng_bridge_config_type }, { NGM_BRIDGE_COOKIE, NGM_BRIDGE_RESET, "reset", NULL, NULL }, { NGM_BRIDGE_COOKIE, NGM_BRIDGE_GET_STATS, "getstats", &ng_parse_uint32_type, &ng_bridge_stats_type }, { NGM_BRIDGE_COOKIE, NGM_BRIDGE_CLR_STATS, "clrstats", &ng_parse_uint32_type, NULL }, { NGM_BRIDGE_COOKIE, NGM_BRIDGE_GETCLR_STATS, "getclrstats", &ng_parse_uint32_type, &ng_bridge_stats_type }, { NGM_BRIDGE_COOKIE, NGM_BRIDGE_GET_TABLE, "gettable", NULL, &ng_bridge_host_ary_type }, { NGM_BRIDGE_COOKIE, NGM_BRIDGE_SET_PERSISTENT, "setpersistent", NULL, NULL }, { NGM_BRIDGE_COOKIE, NGM_BRIDGE_MOVE_HOST, "movehost", &ng_bridge_move_host_type, NULL }, { 0 } }; /* Node type descriptor */ static struct ng_type ng_bridge_typestruct = { .version = NG_ABI_VERSION, .name = NG_BRIDGE_NODE_TYPE, .constructor = ng_bridge_constructor, .rcvmsg = ng_bridge_rcvmsg, .shutdown = ng_bridge_shutdown, .newhook = ng_bridge_newhook, .rcvdata = ng_bridge_rcvdata, .disconnect = ng_bridge_disconnect, .cmdlist = ng_bridge_cmdlist, }; NETGRAPH_INIT(bridge, &ng_bridge_typestruct); /****************************************************************** NETGRAPH NODE METHODS ******************************************************************/ /* * Node constructor */ static int ng_bridge_constructor(node_p node) { priv_p priv; /* Allocate and initialize private info */ priv = malloc(sizeof(*priv), M_NETGRAPH_BRIDGE, M_WAITOK | M_ZERO); ng_callout_init(&priv->timer); /* Allocate and initialize hash table, etc. */ priv->tab = malloc(MIN_BUCKETS * sizeof(*priv->tab), M_NETGRAPH_BRIDGE, M_WAITOK | M_ZERO); priv->numBuckets = MIN_BUCKETS; priv->hashMask = MIN_BUCKETS - 1; priv->conf.debugLevel = 1; priv->conf.loopTimeout = DEFAULT_LOOP_TIMEOUT; priv->conf.maxStaleness = DEFAULT_MAX_STALENESS; priv->conf.minStableAge = DEFAULT_MIN_STABLE_AGE; priv->sendUnknown = 1; /* classic bridge */ NG_NODE_SET_PRIVATE(node, priv); priv->node = node; /* Start timer; timer is always running while node is alive */ ng_callout(&priv->timer, node, NULL, hz, ng_bridge_timeout, NULL, 0); /* Done */ return (0); } /* * Method for attaching a new hook */ static int ng_bridge_newhook(node_p node, hook_p hook, const char *name) { const priv_p priv = NG_NODE_PRIVATE(node); char linkName[NG_HOOKSIZ]; u_int32_t linkNum; link_p link; const char *prefix = NG_BRIDGE_HOOK_LINK_PREFIX; bool isUplink; /* Check for a link hook */ if (strlen(name) <= strlen(prefix)) return (EINVAL); /* Unknown hook name */ isUplink = (name[0] == 'u'); if (isUplink) prefix = NG_BRIDGE_HOOK_UPLINK_PREFIX; /* primitive parsing */ linkNum = strtoul(name + strlen(prefix), NULL, 10); /* validation by comparing against the reconstucted name */ snprintf(linkName, sizeof(linkName), "%s%u", prefix, linkNum); if (strcmp(linkName, name) != 0) return (EINVAL); if (linkNum == 0 && isUplink) return (EINVAL); if(NG_PEER_NODE(hook) == node) return (ELOOP); link = malloc(sizeof(*link), M_NETGRAPH_BRIDGE, M_NOWAIT | M_ZERO); if (link == NULL) return (ENOMEM); #define NG_BRIDGE_COUNTER_ALLOC(f) do { \ link->stats.f = counter_u64_alloc(M_NOWAIT); \ if (link->stats.f == NULL) \ goto nomem; \ } while (0) NG_BRIDGE_COUNTER_ALLOC(recvOctets); NG_BRIDGE_COUNTER_ALLOC(recvPackets); NG_BRIDGE_COUNTER_ALLOC(recvMulticasts); NG_BRIDGE_COUNTER_ALLOC(recvBroadcasts); NG_BRIDGE_COUNTER_ALLOC(recvUnknown); NG_BRIDGE_COUNTER_ALLOC(recvRunts); NG_BRIDGE_COUNTER_ALLOC(recvInvalid); NG_BRIDGE_COUNTER_ALLOC(xmitOctets); NG_BRIDGE_COUNTER_ALLOC(xmitPackets); NG_BRIDGE_COUNTER_ALLOC(xmitMulticasts); NG_BRIDGE_COUNTER_ALLOC(xmitBroadcasts); NG_BRIDGE_COUNTER_ALLOC(loopDrops); NG_BRIDGE_COUNTER_ALLOC(memoryFailures); #undef NG_BRIDGE_COUNTER_ALLOC link->hook = hook; if (isUplink) { link->learnMac = 0; link->sendUnknown = 1; if (priv->numLinks == 0) /* if the first link is an uplink */ priv->sendUnknown = 0; /* switch to restrictive mode */ } else { link->learnMac = 1; link->sendUnknown = priv->sendUnknown; } NG_HOOK_SET_PRIVATE(hook, link); priv->numLinks++; return (0); nomem: ng_bridge_free_link(link); return (ENOMEM); } /* * Receive a control message */ static void ng_bridge_clear_link_stats(struct ng_bridge_link_kernel_stats *p) { counter_u64_zero(p->recvOctets); counter_u64_zero(p->recvPackets); counter_u64_zero(p->recvMulticasts); counter_u64_zero(p->recvBroadcasts); counter_u64_zero(p->recvUnknown); counter_u64_zero(p->recvRunts); counter_u64_zero(p->recvInvalid); counter_u64_zero(p->xmitOctets); counter_u64_zero(p->xmitPackets); counter_u64_zero(p->xmitMulticasts); counter_u64_zero(p->xmitBroadcasts); counter_u64_zero(p->loopDrops); p->loopDetects = 0; counter_u64_zero(p->memoryFailures); } static void ng_bridge_free_link(link_p link) { counter_u64_free(link->stats.recvOctets); counter_u64_free(link->stats.recvPackets); counter_u64_free(link->stats.recvMulticasts); counter_u64_free(link->stats.recvBroadcasts); counter_u64_free(link->stats.recvUnknown); counter_u64_free(link->stats.recvRunts); counter_u64_free(link->stats.recvInvalid); counter_u64_free(link->stats.xmitOctets); counter_u64_free(link->stats.xmitPackets); counter_u64_free(link->stats.xmitMulticasts); counter_u64_free(link->stats.xmitBroadcasts); counter_u64_free(link->stats.loopDrops); counter_u64_free(link->stats.memoryFailures); free(link, M_NETGRAPH_BRIDGE); } static int ng_bridge_reset_link(hook_p hook, void *arg __unused) { link_p priv = NG_HOOK_PRIVATE(hook); priv->loopCount = 0; ng_bridge_clear_link_stats(&priv->stats); return (1); } static int ng_bridge_rcvmsg(node_p node, item_p item, hook_p lasthook) { const priv_p priv = NG_NODE_PRIVATE(node); struct ng_mesg *resp = NULL; int error = 0; struct ng_mesg *msg; NGI_GET_MSG(item, msg); switch (msg->header.typecookie) { case NGM_BRIDGE_COOKIE: switch (msg->header.cmd) { case NGM_BRIDGE_GET_CONFIG: { struct ng_bridge_config *conf; NG_MKRESPONSE(resp, msg, sizeof(struct ng_bridge_config), M_NOWAIT); if (resp == NULL) { error = ENOMEM; break; } conf = (struct ng_bridge_config *)resp->data; *conf = priv->conf; /* no sanity checking needed */ break; } case NGM_BRIDGE_SET_CONFIG: { struct ng_bridge_config *conf; if (msg->header.arglen != sizeof(struct ng_bridge_config)) { error = EINVAL; break; } conf = (struct ng_bridge_config *)msg->data; priv->conf = *conf; break; } case NGM_BRIDGE_RESET: { hook_p rethook; /* Flush all entries in the hash table */ ng_bridge_remove_hosts(priv, NULL); /* Reset all loop detection counters and stats */ NG_NODE_FOREACH_HOOK(node, ng_bridge_reset_link, NULL, rethook); break; } case NGM_BRIDGE_GET_STATS: case NGM_BRIDGE_CLR_STATS: case NGM_BRIDGE_GETCLR_STATS: { hook_p hook; link_p link; char linkName[NG_HOOKSIZ]; int linkNum; /* Get link number */ if (msg->header.arglen != sizeof(u_int32_t)) { error = EINVAL; break; } linkNum = *((int32_t *)msg->data); if (linkNum < 0) snprintf(linkName, sizeof(linkName), "%s%u", NG_BRIDGE_HOOK_UPLINK_PREFIX, -linkNum); else snprintf(linkName, sizeof(linkName), "%s%u", NG_BRIDGE_HOOK_LINK_PREFIX, linkNum); if ((hook = ng_findhook(node, linkName)) == NULL) { error = ENOTCONN; break; } link = NG_HOOK_PRIVATE(hook); /* Get/clear stats */ if (msg->header.cmd != NGM_BRIDGE_CLR_STATS) { struct ng_bridge_link_stats *rs; NG_MKRESPONSE(resp, msg, sizeof(link->stats), M_NOWAIT); if (resp == NULL) { error = ENOMEM; break; } rs = (struct ng_bridge_link_stats *)resp->data; #define FETCH(x) rs->x = counter_u64_fetch(link->stats.x) FETCH(recvOctets); FETCH(recvPackets); FETCH(recvMulticasts); FETCH(recvBroadcasts); FETCH(recvUnknown); FETCH(recvRunts); FETCH(recvInvalid); FETCH(xmitOctets); FETCH(xmitPackets); FETCH(xmitMulticasts); FETCH(xmitBroadcasts); FETCH(loopDrops); rs->loopDetects = link->stats.loopDetects; FETCH(memoryFailures); #undef FETCH } if (msg->header.cmd != NGM_BRIDGE_GET_STATS) ng_bridge_clear_link_stats(&link->stats); break; } case NGM_BRIDGE_GET_TABLE: { struct ng_bridge_host_ary *ary; struct ng_bridge_host *host; int i = 0, bucket; NG_MKRESPONSE(resp, msg, sizeof(*ary) + (priv->numHosts * sizeof(*ary->hosts)), M_NOWAIT); if (resp == NULL) { error = ENOMEM; break; } ary = (struct ng_bridge_host_ary *)resp->data; ary->numHosts = priv->numHosts; for (bucket = 0; bucket < priv->numBuckets; bucket++) { SLIST_FOREACH(host, &priv->tab[bucket], next) { memcpy(ary->hosts[i].addr, host->addr, sizeof(ary->hosts[i].addr)); ary->hosts[i].age = host->age; ary->hosts[i].staleness = host->staleness; strncpy(ary->hosts[i].hook, NG_HOOK_NAME(host->link->hook), sizeof(ary->hosts[i].hook)); i++; } } break; } case NGM_BRIDGE_SET_PERSISTENT: { priv->persistent = 1; break; } case NGM_BRIDGE_MOVE_HOST: { struct ng_bridge_move_host *mh; hook_p hook; if (msg->header.arglen < sizeof(*mh)) { error = EINVAL; break; } mh = (struct ng_bridge_move_host *)msg->data; hook = (mh->hook[0] == 0) ? lasthook : ng_findhook(node, mh->hook); if (hook == NULL) { error = ENOENT; break; } error = ng_bridge_put(priv, mh->addr, NG_HOOK_PRIVATE(hook)); break; } default: error = EINVAL; break; } break; default: error = EINVAL; break; } /* Done */ NG_RESPOND_MSG(error, node, item, resp); NG_FREE_MSG(msg); return (error); } /* * Receive data on a hook */ struct ng_bridge_send_ctx { link_p foundFirst, incoming; struct mbuf * m; int manycast, error; }; /* * Update stats and send out */ static inline int ng_bridge_send_data(link_cp dst, int manycast, struct mbuf *m, item_p item) { int error = 0; size_t len = m->m_pkthdr.len; if(item != NULL) NG_FWD_NEW_DATA(error, item, dst->hook, m); else NG_SEND_DATA_ONLY(error, dst->hook, m); if (error) { if (error == ENOMEM) counter_u64_add(dst->stats.memoryFailures, 1); /* The packet is still ours */ if (item != NULL) NG_FREE_ITEM(item); if (m != NULL) NG_FREE_M(m); return (error); } counter_u64_add(dst->stats.xmitPackets, 1); counter_u64_add(dst->stats.xmitOctets, len); switch (manycast) { default: /* unknown unicast */ break; case 1: /* multicast */ counter_u64_add(dst->stats.xmitMulticasts, 1); break; case 2: /* broadcast */ counter_u64_add(dst->stats.xmitBroadcasts, 1); break; } return (0); } /* * Loop body for sending to multiple destinations * return 0 to stop looping */ static int ng_bridge_send_ctx(hook_p dst, void *arg) { struct ng_bridge_send_ctx *ctx = arg; link_p destLink = NG_HOOK_PRIVATE(dst); struct mbuf *m2 = NULL; int error = 0; /* Skip incoming link */ if (destLink == ctx->incoming) { return (1); } /* Skip sending unknowns to undesired links */ if (!ctx->manycast && !destLink->sendUnknown) return (1); if (ctx->foundFirst == NULL) { /* * This is the first usable link we have found. * Reserve it for the originals. * If we never find another we save a copy. */ ctx->foundFirst = destLink; return (1); } /* * It's usable link but not the reserved (first) one. * Copy mbuf info for sending. */ m2 = m_dup(ctx->m, M_NOWAIT); if (m2 == NULL) { counter_u64_add(ctx->incoming->stats.memoryFailures, 1); ctx->error = ENOBUFS; return (0); /* abort loop, do not try again and again */ } /* Send packet */ error = ng_bridge_send_data(destLink, ctx->manycast, m2, NULL); if (error) ctx->error = error; return (1); } static int ng_bridge_rcvdata(hook_p hook, item_p item) { const node_p node = NG_HOOK_NODE(hook); const priv_p priv = NG_NODE_PRIVATE(node); struct ng_bridge_host *host; struct ether_header *eh; struct ng_bridge_send_ctx ctx = { 0 }; hook_p ret; NGI_GET_M(item, ctx.m); ctx.incoming = NG_HOOK_PRIVATE(hook); /* Sanity check packet and pull up header */ if (ctx.m->m_pkthdr.len < ETHER_HDR_LEN) { counter_u64_add(ctx.incoming->stats.recvRunts, 1); NG_FREE_ITEM(item); NG_FREE_M(ctx.m); return (EINVAL); } if (ctx.m->m_len < ETHER_HDR_LEN && !(ctx.m = m_pullup(ctx.m, ETHER_HDR_LEN))) { counter_u64_add(ctx.incoming->stats.memoryFailures, 1); NG_FREE_ITEM(item); return (ENOBUFS); } eh = mtod(ctx.m, struct ether_header *); if ((eh->ether_shost[0] & 1) != 0) { counter_u64_add(ctx.incoming->stats.recvInvalid, 1); NG_FREE_ITEM(item); NG_FREE_M(ctx.m); return (EINVAL); } /* Is link disabled due to a loopback condition? */ if (ctx.incoming->loopCount != 0) { counter_u64_add(ctx.incoming->stats.loopDrops, 1); NG_FREE_ITEM(item); NG_FREE_M(ctx.m); return (ELOOP); } /* Update stats */ counter_u64_add(ctx.incoming->stats.recvPackets, 1); counter_u64_add(ctx.incoming->stats.recvOctets, ctx.m->m_pkthdr.len); if ((ctx.manycast = (eh->ether_dhost[0] & 1)) != 0) { if (ETHER_EQUAL(eh->ether_dhost, ng_bridge_bcast_addr)) { counter_u64_add(ctx.incoming->stats.recvBroadcasts, 1); ctx.manycast = 2; } else counter_u64_add(ctx.incoming->stats.recvMulticasts, 1); } /* Look up packet's source Ethernet address in hashtable */ if ((host = ng_bridge_get(priv, eh->ether_shost)) != NULL) /* Update time since last heard from this host. * This is safe without locking, because it's * the only operation during shared access. */ if (__predict_false(host->staleness > 0)) host->staleness = 0; if ((host == NULL && ctx.incoming->learnMac) || (host != NULL && host->link != ctx.incoming)) { struct ng_mesg *msg; struct ng_bridge_move_host *mh; int error = 0; NG_MKMESSAGE(msg, NGM_BRIDGE_COOKIE, NGM_BRIDGE_MOVE_HOST, sizeof(*mh), M_NOWAIT); if (msg == NULL) { counter_u64_add(ctx.incoming->stats.memoryFailures, 1); NG_FREE_ITEM(item); NG_FREE_M(ctx.m); return (ENOMEM); } mh = (struct ng_bridge_move_host *)msg->data; strncpy(mh->hook, NG_HOOK_NAME(ctx.incoming->hook), sizeof(mh->hook)); memcpy(mh->addr, eh->ether_shost, sizeof(mh->addr)); NG_SEND_MSG_ID(error, node, msg, NG_NODE_ID(node), NG_NODE_ID(node)); if (error) counter_u64_add(ctx.incoming->stats.memoryFailures, 1); } if (host != NULL && host->link != ctx.incoming) { if (host->age < priv->conf.minStableAge) { /* Drop packet on instable links */ counter_u64_add(ctx.incoming->stats.loopDrops, 1); NG_FREE_ITEM(item); NG_FREE_M(ctx.m); return (ELOOP); } } /* Run packet through ipfw processing, if enabled */ #if 0 if (priv->conf.ipfw[linkNum] && V_fw_enable && V_ip_fw_chk_ptr != NULL) { /* XXX not implemented yet */ } #endif /* * If unicast and destination host known, deliver to host's link, * unless it is the same link as the packet came in on. */ if (!ctx.manycast) { /* Determine packet destination link */ if ((host = ng_bridge_get(priv, eh->ether_dhost)) != NULL) { link_p destLink = host->link; /* If destination same as incoming link, do nothing */ if (destLink == ctx.incoming) { NG_FREE_ITEM(item); NG_FREE_M(ctx.m); return (0); } /* Deliver packet out the destination link */ return (ng_bridge_send_data(destLink, ctx.manycast, ctx.m, item)); } /* Destination host is not known */ counter_u64_add(ctx.incoming->stats.recvUnknown, 1); } /* Distribute unknown, multicast, broadcast pkts to all other links */ NG_NODE_FOREACH_HOOK(node, ng_bridge_send_ctx, &ctx, ret); /* Finally send out on the first link found */ if (ctx.foundFirst != NULL) { int error = ng_bridge_send_data(ctx.foundFirst, ctx.manycast, ctx.m, item); if (error) ctx.error = error; } else { /* nothing to send at all */ NG_FREE_ITEM(item); NG_FREE_M(ctx.m); } return (ctx.error); } /* * Shutdown node */ static int ng_bridge_shutdown(node_p node) { const priv_p priv = NG_NODE_PRIVATE(node); /* * Shut down everything including the timer. Even if the * callout has already been dequeued and is about to be * run, ng_bridge_timeout() won't be fired as the node * is already marked NGF_INVALID, so we're safe to free * the node now. */ KASSERT(priv->numLinks == 0 && priv->numHosts == 0, ("%s: numLinks=%d numHosts=%d", __func__, priv->numLinks, priv->numHosts)); ng_uncallout(&priv->timer, node); NG_NODE_SET_PRIVATE(node, NULL); NG_NODE_UNREF(node); free(priv->tab, M_NETGRAPH_BRIDGE); free(priv, M_NETGRAPH_BRIDGE); return (0); } /* * Hook disconnection. */ static int ng_bridge_disconnect(hook_p hook) { const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook)); link_p link = NG_HOOK_PRIVATE(hook); /* Remove all hosts associated with this link */ ng_bridge_remove_hosts(priv, link); /* Free associated link information */ ng_bridge_free_link(link); priv->numLinks--; /* If no more hooks, go away */ if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0) && (NG_NODE_IS_VALID(NG_HOOK_NODE(hook))) && !priv->persistent) { ng_rmnode_self(NG_HOOK_NODE(hook)); } return (0); } /****************************************************************** HASH TABLE FUNCTIONS ******************************************************************/ /* * Hash algorithm */ #define HASH(addr,mask) ( (((const u_int16_t *)(addr))[0] \ ^ ((const u_int16_t *)(addr))[1] \ ^ ((const u_int16_t *)(addr))[2]) & (mask) ) /* * Find a host entry in the table. */ static struct ng_bridge_host * ng_bridge_get(priv_cp priv, const u_char *addr) { const int bucket = HASH(addr, priv->hashMask); struct ng_bridge_host *host; SLIST_FOREACH(host, &priv->tab[bucket], next) { if (ETHER_EQUAL(host->addr, addr)) return (host); } return (NULL); } /* * Add a host entry to the table. If it already exists, move it * to the new link. Returns 0 on success. */ static int ng_bridge_put(priv_p priv, const u_char *addr, link_p link) { const int bucket = HASH(addr, priv->hashMask); struct ng_bridge_host *host; if ((host = ng_bridge_get(priv, addr)) != NULL) { /* Host already on the correct link? */ if (host->link == link) return 0; /* Move old host over to new link */ if (host->age >= priv->conf.minStableAge) { host->link = link; host->age = 0; return (0); } /* * If the host was recently moved to the old link and * it's now jumping to a new link, declare a loopback * condition. */ if (priv->conf.debugLevel >= 2) log(LOG_WARNING, "ng_bridge: %s:" " loopback detected on %s\n", ng_bridge_nodename(priv->node), NG_HOOK_NAME(link->hook)); /* Mark link as linka non grata */ link->loopCount = priv->conf.loopTimeout; link->stats.loopDetects++; /* Forget all hosts on this link */ ng_bridge_remove_hosts(priv, link); return (ELOOP); } /* Allocate and initialize new hashtable entry */ host = malloc(sizeof(*host), M_NETGRAPH_BRIDGE, M_NOWAIT); if (host == NULL) return (ENOMEM); bcopy(addr, host->addr, ETHER_ADDR_LEN); host->link = link; host->staleness = 0; host->age = 0; /* Add new element to hash bucket */ SLIST_INSERT_HEAD(&priv->tab[bucket], host, next); priv->numHosts++; /* Resize table if necessary */ ng_bridge_rehash(priv); return (0); } /* * Resize the hash table. We try to maintain the number of buckets * such that the load factor is in the range 0.25 to 1.0. * * If we can't get the new memory then we silently fail. This is OK * because things will still work and we'll try again soon anyway. */ static void ng_bridge_rehash(priv_p priv) { struct ng_bridge_bucket *newTab; int oldBucket, newBucket; int newNumBuckets; u_int newMask; /* Is table too full or too empty? */ if (priv->numHosts > priv->numBuckets && (priv->numBuckets << 1) <= MAX_BUCKETS) newNumBuckets = priv->numBuckets << 1; else if (priv->numHosts < (priv->numBuckets >> 2) && (priv->numBuckets >> 2) >= MIN_BUCKETS) newNumBuckets = priv->numBuckets >> 2; else return; newMask = newNumBuckets - 1; /* Allocate and initialize new table */ newTab = malloc(newNumBuckets * sizeof(*newTab), M_NETGRAPH_BRIDGE, M_NOWAIT | M_ZERO); if (newTab == NULL) return; /* Move all entries from old table to new table */ for (oldBucket = 0; oldBucket < priv->numBuckets; oldBucket++) { struct ng_bridge_bucket *const oldList = &priv->tab[oldBucket]; while (!SLIST_EMPTY(oldList)) { struct ng_bridge_host *const host = SLIST_FIRST(oldList); SLIST_REMOVE_HEAD(oldList, next); newBucket = HASH(host->addr, newMask); SLIST_INSERT_HEAD(&newTab[newBucket], host, next); } } /* Replace old table with new one */ if (priv->conf.debugLevel >= 3) { log(LOG_INFO, "ng_bridge: %s: table size %d -> %d\n", ng_bridge_nodename(priv->node), priv->numBuckets, newNumBuckets); } free(priv->tab, M_NETGRAPH_BRIDGE); priv->numBuckets = newNumBuckets; priv->hashMask = newMask; priv->tab = newTab; return; } /****************************************************************** MISC FUNCTIONS ******************************************************************/ /* * Remove all hosts associated with a specific link from the hashtable. * If linkNum == -1, then remove all hosts in the table. */ static void ng_bridge_remove_hosts(priv_p priv, link_p link) { int bucket; for (bucket = 0; bucket < priv->numBuckets; bucket++) { struct ng_bridge_host **hptr = &SLIST_FIRST(&priv->tab[bucket]); while (*hptr != NULL) { struct ng_bridge_host *const host = *hptr; if (link == NULL || host->link == link) { *hptr = SLIST_NEXT(host, next); free(host, M_NETGRAPH_BRIDGE); priv->numHosts--; } else hptr = &SLIST_NEXT(host, next); } } } /* * Handle our once-per-second timeout event. We do two things: * we decrement link->loopCount for those links being muted due to * a detected loopback condition, and we remove any hosts from * the hashtable whom we haven't heard from in a long while. */ static int ng_bridge_unmute(hook_p hook, void *arg) { link_p link = NG_HOOK_PRIVATE(hook); node_p node = NG_HOOK_NODE(hook); priv_p priv = NG_NODE_PRIVATE(node); int *counter = arg; if (link->loopCount != 0) { link->loopCount--; if (link->loopCount == 0 && priv->conf.debugLevel >= 2) { log(LOG_INFO, "ng_bridge: %s:" " restoring looped back %s\n", ng_bridge_nodename(node), NG_HOOK_NAME(hook)); } } (*counter)++; return (1); } static void ng_bridge_timeout(node_p node, hook_p hook, void *arg1, int arg2) { const priv_p priv = NG_NODE_PRIVATE(node); int bucket; int counter = 0; hook_p ret; /* Update host time counters and remove stale entries */ for (bucket = 0; bucket < priv->numBuckets; bucket++) { struct ng_bridge_host **hptr = &SLIST_FIRST(&priv->tab[bucket]); while (*hptr != NULL) { struct ng_bridge_host *const host = *hptr; /* Remove hosts we haven't heard from in a while */ if (++host->staleness >= priv->conf.maxStaleness) { *hptr = SLIST_NEXT(host, next); free(host, M_NETGRAPH_BRIDGE); priv->numHosts--; } else { if (host->age < 0xffff) host->age++; hptr = &SLIST_NEXT(host, next); counter++; } } } KASSERT(priv->numHosts == counter, ("%s: hosts: %d != %d", __func__, priv->numHosts, counter)); /* Decrease table size if necessary */ ng_bridge_rehash(priv); /* Decrease loop counter on muted looped back links */ counter = 0; NG_NODE_FOREACH_HOOK(node, ng_bridge_unmute, &counter, ret); KASSERT(priv->numLinks == counter, ("%s: links: %d != %d", __func__, priv->numLinks, counter)); /* Register a new timeout, keeping the existing node reference */ ng_callout(&priv->timer, node, NULL, hz, ng_bridge_timeout, NULL, 0); } /* * Return node's "name", even if it doesn't have one. */ static const char * ng_bridge_nodename(node_cp node) { static char name[NG_NODESIZ]; if (NG_NODE_HAS_NAME(node)) snprintf(name, sizeof(name), "%s", NG_NODE_NAME(node)); else snprintf(name, sizeof(name), "[%x]", ng_node2ID(node)); return name; }