lib/libifconfig/libifconfig_bridge.c

   1 /*
   2  * Copyright (c) 2020, Ryan Moeller <freqlabs@FreeBSD.org>
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  * 1. Redistributions of source code must retain the above copyright
   8  *    notice, this list of conditions and the following disclaimer.
   9  * 2. Redistributions in binary form must reproduce the above copyright
  10  *    notice, this list of conditions and the following disclaimer in the
  11  *    documentation and/or other materials provided with the distribution.
  12  *
  13  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  14  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  16  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  17  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  18  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  19  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  20  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  21  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  22  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  23  * SUCH DAMAGE.
  24  *
  25  * $FreeBSD$
  26  */
  27 #include <sys/param.h>
  28 #include <sys/ioctl.h>
  29
  30 #include <net/ethernet.h>
  31 #include <net/if.h>
  32 #include <net/if_bridgevar.h>
  33 #include <net/route.h>
  34
  35 #include <assert.h>
  36 #include <errno.h>
  37 #include <stdbool.h>
  38 #include <stdlib.h>
  39 #include <string.h>
  40
  41 #include "libifconfig.h"
  42 #include "libifconfig_internal.h"
  43
  44 /* Internal structure used for allocations and frees */
  45 struct _ifconfig_bridge_status {
  46         struct ifconfig_bridge_status inner;    /* wrapped bridge status */
  47         struct ifbropreq params;                /* operational parameters */
  48 };
  49
  50 static int
  51 ifconfig_bridge_ioctlwrap(ifconfig_handle_t *h, const char *name,
  52     unsigned long cmd, void *arg, size_t arglen, bool set)
  53 {
  54         struct ifdrv ifd = { 0 };
  55         unsigned long req = set ? SIOCSDRVSPEC : SIOCGDRVSPEC;
  56
  57         strlcpy(ifd.ifd_name, name, sizeof(ifd.ifd_name));
  58         ifd.ifd_cmd = cmd;
  59         ifd.ifd_data = arg;
  60         ifd.ifd_len = arglen;
  61
  62         return (ifconfig_ioctlwrap(h, AF_LOCAL, req, &ifd));
  63 }
  64
  65 int
  66 ifconfig_bridge_get_bridge_status(ifconfig_handle_t *h,
  67     const char *name, struct ifconfig_bridge_status **bridgep)
  68 {
  69         struct ifbifconf members;
  70         struct ifbrparam cache_param;
  71         struct _ifconfig_bridge_status *bridge;
  72         char *buf;
  73
  74         *bridgep = NULL;
  75
  76         bridge = calloc(1, sizeof(struct _ifconfig_bridge_status));
  77         if (bridge == NULL) {
  78                 h->error.errtype = OTHER;
  79                 h->error.errcode = ENOMEM;
  80                 return (-1);
  81         }
  82         bridge->inner.params = &bridge->params;
  83
  84         if (ifconfig_bridge_ioctlwrap(h, name, BRDGGCACHE,
  85             &cache_param, sizeof(cache_param), false) != 0) {
  86                 free(bridge);
  87                 return (-1);
  88         }
  89         bridge->inner.cache_size = cache_param.ifbrp_csize;
  90
  91         if (ifconfig_bridge_ioctlwrap(h, name, BRDGGTO,
  92             &cache_param, sizeof(cache_param), false) != 0) {
  93                 free(bridge);
  94                 return (-1);
  95         }
  96         bridge->inner.cache_lifetime = cache_param.ifbrp_ctime;
  97
  98         if (ifconfig_bridge_ioctlwrap(h, name, BRDGPARAM,
  99             &bridge->params, sizeof(bridge->params), false) != 0) {
 100                 free(bridge);
 101                 return (-1);
 102         }
 103
 104         members.ifbic_buf = NULL;
 105         for (size_t len = 8192;
 106             (buf = realloc(members.ifbic_buf, len)) != NULL;
 107             len *= 2) {
 108                 members.ifbic_buf = buf;
 109                 members.ifbic_len = len;
 110                 if (ifconfig_bridge_ioctlwrap(h, name, BRDGGIFS,
 111                     &members, sizeof(members), false) != 0) {
 112                         free(buf);
 113                         free(bridge);
 114                         return (-1);
 115                 }
 116                 if (members.ifbic_len <= len)
 117                         break;
 118         }
 119         if (buf == NULL) {
 120                 free(members.ifbic_buf);
 121                 free(bridge);
 122                 h->error.errtype = OTHER;
 123                 h->error.errcode = ENOMEM;
 124                 return (-1);
 125         }
 126         bridge->inner.members = members.ifbic_req;
 127         bridge->inner.members_count =
 128             members.ifbic_len / sizeof(*members.ifbic_req);
 129
 130         *bridgep = &bridge->inner;
 131
 132         return (0);
 133 }
 134
 135 void
 136 ifconfig_bridge_free_bridge_status(struct ifconfig_bridge_status *bridge)
 137 {
 138         if (bridge != NULL) {
 139                 free(bridge->members);
 140                 free(bridge);
 141         }
 142 }