sys/net/if_mib.c

   1 /*-
   2  * Copyright 1996 Massachusetts Institute of Technology
   3  *
   4  * Permission to use, copy, modify, and distribute this software and
   5  * its documentation for any purpose and without fee is hereby
   6  * granted, provided that both the above copyright notice and this
   7  * permission notice appear in all copies, that both the above
   8  * copyright notice and this permission notice appear in all
   9  * supporting documentation, and that the name of M.I.T. not be used
  10  * in advertising or publicity pertaining to distribution of the
  11  * software without specific, written prior permission.  M.I.T. makes
  12  * no representations about the suitability of this software for any
  13  * purpose.  It is provided "as is" without express or implied
  14  * warranty.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''.  M.I.T. DISCLAIMS
  17  * ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE,
  18  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  19  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT
  20  * SHALL M.I.T. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  21  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  22  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
  23  * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  24  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  25  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  26  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  */
  29
  30 #include <sys/param.h>
  31 #include <sys/systm.h>
  32 #include <sys/kernel.h>
  33 #include <sys/malloc.h>
  34 #include <sys/socket.h>
  35 #include <sys/sysctl.h>
  36
  37 #include <net/if.h>
  38 #include <net/if_var.h>
  39 #include <net/if_private.h>
  40 #include <net/if_mib.h>
  41 #include <net/vnet.h>
  42
  43 /*
  44  * A sysctl(3) MIB for generic interface information.  This information
  45  * is exported in the net.link.generic branch, which has the following
  46  * structure:
  47  *
  48  * net.link.generic     .system                 - system-wide control variables
  49  *                                                and statistics (node)
  50  *                      .ifdata.<ifindex>.general
  51  *                                              - what's in `struct ifdata'
  52  *                                                plus some other info
  53  *                      .ifdata.<ifindex>.linkspecific
  54  *                                              - a link-type-specific data
  55  *                                                structure (as might be used
  56  *                                                by an SNMP agent
  57  *
  58  * Perhaps someday we will make addresses accessible via this interface
  59  * as well (then there will be four such...).  The reason that the
  60  * index comes before the last element in the name is because it
  61  * seems more orthogonal that way, particularly with the possibility
  62  * of other per-interface data living down here as well (e.g., integrated
  63  * services stuff).
  64  */
  65
  66 static int
  67 sysctl_ifdata(SYSCTL_HANDLER_ARGS) /* XXX bad syntax! */
  68 {
  69         int *name = (int *)arg1;
  70         int error;
  71         u_int namelen = arg2;
  72         struct ifnet *ifp;
  73         struct ifmibdata ifmd;
  74         struct epoch_tracker et;
  75         size_t dlen;
  76         char *dbuf;
  77
  78         if (namelen != 2)
  79                 return EINVAL;
  80         if (name[0] <= 0)
  81                 return (ENOENT);
  82         NET_EPOCH_ENTER(et);
  83         ifp = ifnet_byindex_ref(name[0]);
  84         NET_EPOCH_EXIT(et);
  85         if (ifp == NULL)
  86                 return (ENOENT);
  87
  88         switch(name[1]) {
  89         default:
  90                 error = ENOENT;
  91                 goto out;
  92
  93         case IFDATA_GENERAL:
  94                 bzero(&ifmd, sizeof(ifmd));
  95                 strlcpy(ifmd.ifmd_name, ifp->if_xname, sizeof(ifmd.ifmd_name));
  96
  97                 ifmd.ifmd_pcount = ifp->if_pcount;
  98                 if_data_copy(ifp, &ifmd.ifmd_data);
  99
 100                 ifmd.ifmd_flags = ifp->if_flags | ifp->if_drv_flags;
 101                 ifmd.ifmd_snd_len = ifp->if_snd.ifq_len;
 102                 ifmd.ifmd_snd_maxlen = ifp->if_snd.ifq_maxlen;
 103                 ifmd.ifmd_snd_drops =
 104                     ifp->if_get_counter(ifp, IFCOUNTER_OQDROPS);
 105
 106                 error = SYSCTL_OUT(req, &ifmd, sizeof ifmd);
 107                 if (error)
 108                         goto out;
 109                 break;
 110
 111         case IFDATA_LINKSPECIFIC:
 112                 error = SYSCTL_OUT(req, ifp->if_linkmib, ifp->if_linkmiblen);
 113                 if (error || !req->newptr)
 114                         goto out;
 115                 break;
 116
 117         case IFDATA_DRIVERNAME:
 118                 /* 20 is enough for 64bit ints */
 119                 dlen = strlen(ifp->if_dname) + 20 + 1;
 120                 if ((dbuf = malloc(dlen, M_TEMP, M_NOWAIT)) == NULL) {
 121                         error = ENOMEM;
 122                         goto out;
 123                 }
 124                 if (ifp->if_dunit == IF_DUNIT_NONE)
 125                         strcpy(dbuf, ifp->if_dname);
 126                 else
 127                         sprintf(dbuf, "%s%d", ifp->if_dname, ifp->if_dunit);
 128
 129                 error = SYSCTL_OUT(req, dbuf, strlen(dbuf) + 1);
 130                 if (error == 0 && req->newptr != NULL)
 131                         error = EPERM;
 132                 free(dbuf, M_TEMP);
 133                 goto out;
 134         }
 135 out:
 136         if_rele(ifp);
 137         return error;
 138 }
 139
 140 SYSCTL_DECL(_net_link_generic);
 141 static SYSCTL_NODE(_net_link_generic, IFMIB_IFDATA, ifdata,
 142     CTLFLAG_RD | CTLFLAG_MPSAFE, sysctl_ifdata,
 143     "Interface table");