usr.sbin/vknetd/bridge.c

   1 /*
   2  * Copyright (c) 2008 The DragonFly Project.  All rights reserved.
   3  *
   4  * This code is derived from software contributed to The DragonFly Project
   5  * by Matthew Dillon <dillon@backplane.com>
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  *
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in
  15  *    the documentation and/or other materials provided with the
  16  *    distribution.
  17  * 3. Neither the name of The DragonFly Project nor the names of its
  18  *    contributors may be used to endorse or promote products derived
  19  *    from this software without specific, prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  *
  34  * $DragonFly: src/usr.sbin/vknetd/bridge.c,v 1.1 2008/05/27 01:58:01 dillon Exp $
  35  */
  36 /*
  37  * Bridging code (serialized)
  38  */
  39 #include "vknetd.h"
  40
  41 static TAILQ_HEAD(, bridge) BridgeList = TAILQ_HEAD_INITIALIZER(BridgeList);
  42
  43 /*
  44  * Add the unix domain descriptor to our bridge
  45  */
  46 bridge_t
  47 bridge_add(ioinfo_t io)
  48 {
  49         bridge_t bridge;
  50
  51         bridge = malloc(sizeof(struct bridge));
  52         bzero(bridge, sizeof(*bridge));
  53         bridge->io = io;
  54         TAILQ_INIT(&bridge->mac_list);
  55         TAILQ_INSERT_TAIL(&BridgeList, bridge, entry);
  56
  57         return(bridge);
  58 }
  59
  60 /*
  61  * Remove the unix domain descriptor from our bridge
  62  */
  63 void
  64 bridge_del(bridge_t bridge)
  65 {
  66         mac_t mac;
  67
  68         TAILQ_REMOVE(&BridgeList, bridge, entry);
  69
  70         while ((mac = TAILQ_FIRST(&bridge->mac_list)) != NULL)
  71                 mac_delete(mac);
  72
  73         free(bridge);
  74 }
  75
  76 /*
  77  * Bridge a packet.  The packet is in the following form:
  78  *
  79  *      [src_mac:6][dst_mac:6][packet]
  80  */
  81 void
  82 bridge_packet(bridge_t bridge, u_int8_t *pkt, int bytes)
  83 {
  84         bridge_t scan;
  85         mac_t mac;
  86
  87         if (mac_broadcast(pkt + 6) == 0) {
  88                 mac = mac_find(pkt + 6);
  89                 if (mac == NULL) {
  90                         mac_add(bridge, pkt + 6);
  91                 } else if (mac->bridge != bridge) {
  92                         mac_delete(mac);
  93                         mac_add(bridge, pkt + 6);
  94                 }
  95         }
  96         if (mac_broadcast(pkt + 0) == 0 && (mac = mac_find(pkt + 0)) != NULL) {
  97                 if (mac->bridge != bridge &&
  98                     (mac->bridge->io->istap == 0 || filter_ok(pkt, bytes))) {
  99                         write(mac->bridge->io->fd, pkt, bytes);
 100                 }
 101         } else {
 102                 TAILQ_FOREACH(scan, &BridgeList, entry) {
 103                         if (scan != bridge &&
 104                             (scan->io->istap == 0 || filter_ok(pkt, bytes))) {
 105                                 write(scan->io->fd, pkt, bytes);
 106                         }
 107                 }
 108         }
 109 }
 110