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 #include <sys/param.h>
  26 #include <sys/ioctl.h>
  27
  28 #include <net/ethernet.h>
  29 #include <net/if.h>
  30 #include <net/if_bridgevar.h>
  31 #include <net/route.h>
  32
  33 #include <assert.h>
  34 #include <errno.h>
  35 #include <stdbool.h>
  36 #include <stdlib.h>
  37 #include <string.h>
  38
  39 #include "libifconfig.h"
  40 #include "libifconfig_internal.h"
  41
  42 /* Internal structure used for allocations and frees */
  43 struct _ifconfig_bridge_status {
  44         struct ifconfig_bridge_status inner;    /* wrapped bridge status */
  45         struct ifbropreq params;                /* operational parameters */
  46 };
  47
  48 static int
  49 ifconfig_bridge_ioctlwrap(ifconfig_handle_t *h, const char *name,
  50     unsigned long cmd, void *arg, size_t arglen, bool set)
  51 {
  52         struct ifdrv ifd = { 0 };
  53         unsigned long req = set ? SIOCSDRVSPEC : SIOCGDRVSPEC;
  54
  55         strlcpy(ifd.ifd_name, name, sizeof(ifd.ifd_name));
  56         ifd.ifd_cmd = cmd;
  57         ifd.ifd_data = arg;
  58         ifd.ifd_len = arglen;
  59
  60         return (ifconfig_ioctlwrap(h, AF_LOCAL, req, &ifd));
  61 }
  62
  63 int
  64 ifconfig_bridge_get_bridge_status(ifconfig_handle_t *h,
  65     const char *name, struct ifconfig_bridge_status **bridgep)
  66 {
  67         struct ifbifconf members;
  68         struct ifbrparam cache_param;
  69         struct _ifconfig_bridge_status *bridge;
  70         char *buf;
  71
  72         *bridgep = NULL;
  73
  74         bridge = calloc(1, sizeof(struct _ifconfig_bridge_status));
  75         if (bridge == NULL) {
  76                 h->error.errtype = OTHER;
  77                 h->error.errcode = ENOMEM;
  78                 return (-1);
  79         }
  80         bridge->inner.params = &bridge->params;
  81
  82         if (ifconfig_bridge_ioctlwrap(h, name, BRDGGCACHE,
  83             &cache_param, sizeof(cache_param), false) != 0) {
  84                 free(bridge);
  85                 return (-1);
  86         }
  87         bridge->inner.cache_size = cache_param.ifbrp_csize;
  88
  89         if (ifconfig_bridge_ioctlwrap(h, name, BRDGGTO,
  90             &cache_param, sizeof(cache_param), false) != 0) {
  91                 free(bridge);
  92                 return (-1);
  93         }
  94         bridge->inner.cache_lifetime = cache_param.ifbrp_ctime;
  95
  96         if (ifconfig_bridge_ioctlwrap(h, name, BRDGPARAM,
  97             &bridge->params, sizeof(bridge->params), false) != 0) {
  98                 free(bridge);
  99                 return (-1);
 100         }
 101
 102         members.ifbic_buf = NULL;
 103         for (size_t len = 8192;
 104             (buf = realloc(members.ifbic_buf, len)) != NULL;
 105             len *= 2) {
 106                 members.ifbic_buf = buf;
 107                 members.ifbic_len = len;
 108                 if (ifconfig_bridge_ioctlwrap(h, name, BRDGGIFS,
 109                     &members, sizeof(members), false) != 0) {
 110                         free(buf);
 111                         free(bridge);
 112                         return (-1);
 113                 }
 114                 if (members.ifbic_len <= len)
 115                         break;
 116         }
 117         if (buf == NULL) {
 118                 free(members.ifbic_buf);
 119                 free(bridge);
 120                 h->error.errtype = OTHER;
 121                 h->error.errcode = ENOMEM;
 122                 return (-1);
 123         }
 124         bridge->inner.members = members.ifbic_req;
 125         bridge->inner.members_count =
 126             members.ifbic_len / sizeof(*members.ifbic_req);
 127
 128         *bridgep = &bridge->inner;
 129
 130         return (0);
 131 }
 132
 133 void
 134 ifconfig_bridge_free_bridge_status(struct ifconfig_bridge_status *bridge)
 135 {
 136         if (bridge != NULL) {
 137                 free(bridge->members);
 138                 free(bridge);
 139         }
 140 }