bsd/net/multicast_list.c

   1 /*
   2  * Copyright (c) 2006 Apple Computer, Inc. All Rights Reserved.
   3  *
   4  * @APPLE_LICENSE_OSREFERENCE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License.  The rights granted to you under the
  10  * License may not be used to create, or enable the creation or
  11  * redistribution of, unlawful or unlicensed copies of an Apple operating
  12  * system, or to circumvent, violate, or enable the circumvention or
  13  * violation of, any terms of an Apple operating system software license
  14  * agreement.
  15  *
  16  * Please obtain a copy of the License at
  17  * http://www.opensource.apple.com/apsl/ and read it before using this
  18  * file.
  19  *
  20  * The Original Code and all software distributed under the License are
  21  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  22  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  23  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  24  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  25  * Please see the License for the specific language governing rights and
  26  * limitations under the License.
  27  *
  28  * @APPLE_LICENSE_OSREFERENCE_HEADER_END@
  29  */
  30
  31 /*
  32  * multicast_util.c:
  33  * - keep track of multicast addresses added to one interface based on the
  34  *   actual multicast addresses in another
  35  * - used by VLAN and BOND
  36  */
  37
  38 /*
  39  * Modification History:
  40  *
  41  * April 29, 2004       Dieter Siegmund (dieter@apple.com)
  42  * - created
  43  */
  44
  45 #include <net/multicast_list.h>
  46 #include <sys/param.h>
  47 #include <sys/systm.h>
  48 #include <sys/malloc.h>
  49 #include <net/if_dl.h>
  50
  51 __private_extern__ void
  52 multicast_list_init(struct multicast_list * mc_list)
  53 {
  54     SLIST_INIT(mc_list);
  55     return;
  56 }
  57
  58 /*
  59  * Function: multicast_list_remove
  60  * Purpose:
  61  *   Remove the given list of multicast addresses from the interface and from
  62  *   the multicast list structure.
  63  */
  64 __private_extern__ int
  65 multicast_list_remove(struct multicast_list * mc_list)
  66 {
  67     int                         error;
  68     struct multicast_entry *    mc;
  69     int                         result = 0;
  70
  71     while ((mc = SLIST_FIRST(mc_list)) != NULL) {
  72         error = ifnet_remove_multicast(mc->mc_ifma);
  73         if (error != 0) {
  74             result = error;
  75         }
  76         SLIST_REMOVE_HEAD(mc_list, mc_entries);
  77         ifmaddr_release(mc->mc_ifma);
  78         FREE(mc, M_DEVBUF);
  79     }
  80     return (result);
  81 }
  82
  83 /*
  84  * Function: multicast_list_program
  85  * Purpose:
  86  *   Program the multicast filter on "target_ifp" using the values from
  87  *   "source_ifp", and saving the result in "mc_list"
  88  *
  89  *   We build a new list of multicast addresses while programming the new list.
  90  *   If that completes successfully, we remove the old list, and return the
  91  *   new list.
  92  *
  93  *   If it fails, we remove what we've added to the new list, and
  94  *   return an error.
  95  */
  96 __private_extern__ int
  97 multicast_list_program(struct multicast_list * mc_list,
  98                        struct ifnet * source_ifp,
  99                        struct ifnet * target_ifp)
 100 {
 101     int                         alen;
 102     int                         error = 0;
 103     int                         i;
 104     struct multicast_entry *    mc = NULL;
 105     struct multicast_list       new_mc_list;
 106     struct sockaddr_dl          source_sdl;
 107     ifmultiaddr_t *             source_multicast_list;
 108     struct sockaddr_dl          target_sdl;
 109
 110     alen = target_ifp->if_addrlen;
 111     bzero((char *)&target_sdl, sizeof(target_sdl));
 112     target_sdl.sdl_len = sizeof(target_sdl);
 113     target_sdl.sdl_family = AF_LINK;
 114     target_sdl.sdl_type = target_ifp->if_type;
 115     target_sdl.sdl_alen = alen;
 116     target_sdl.sdl_index = target_ifp->if_index;
 117
 118     /* build a new list */
 119     multicast_list_init(&new_mc_list);
 120     error = ifnet_get_multicast_list(source_ifp, &source_multicast_list);
 121     if (error != 0) {
 122         printf("multicast_list_program: "
 123                "ifnet_get_multicast_list(%s%d) failed, %d\n",
 124                source_ifp->if_name, source_ifp->if_unit, error);
 125         return (error);
 126     }
 127     for (i = 0; source_multicast_list[i] != NULL; i++) {
 128         if (ifmaddr_address(source_multicast_list[i],
 129                             (struct sockaddr *)&source_sdl,
 130                             sizeof(source_sdl)) != 0
 131             || source_sdl.sdl_family != AF_LINK) {
 132             continue;
 133         }
 134         mc = _MALLOC(sizeof(struct multicast_entry), M_DEVBUF, M_WAITOK);
 135         bcopy(LLADDR(&source_sdl), LLADDR(&target_sdl), alen);
 136         error = ifnet_add_multicast(target_ifp, (struct sockaddr *)&target_sdl,
 137                                     &mc->mc_ifma);
 138         if (error != 0) {
 139             FREE(mc, M_DEVBUF);
 140             break;
 141         }
 142         SLIST_INSERT_HEAD(&new_mc_list, mc, mc_entries);
 143     }
 144     if (error != 0) {
 145         /* restore previous state */
 146         (void)multicast_list_remove(&new_mc_list);
 147     } else {
 148         /* remove the old entries, and return the new list */
 149         (void)multicast_list_remove(mc_list);
 150         *mc_list = new_mc_list;
 151     }
 152     return (error);
 153 }