usr/src/cmd/xvm/ipagent/ipagent.ksh

   1 #!/bin/ksh
   2 #
   3 # CDDL HEADER START
   4 #
   5 # The contents of this file are subject to the terms of the
   6 # Common Development and Distribution License (the "License").
   7 # You may not use this file except in compliance with the License.
   8 #
   9 # You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10 # or http://www.opensolaris.org/os/licensing.
  11 # See the License for the specific language governing permissions
  12 # and limitations under the License.
  13 #
  14 # When distributing Covered Code, include this CDDL HEADER in each
  15 # file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16 # If applicable, add the following below this CDDL HEADER, with the
  17 # fields enclosed by brackets "[]" replaced with your own identifying
  18 # information: Portions Copyright [yyyy] [name of copyright owner]
  19 #
  20 # CDDL HEADER END
  21 #
  22
  23 # Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
  24 # Use is subject to license terms.
  25
  26 #
  27 # xVM PV domU IP address reporting agent. Reports IP address back to dom0.
  28 #
  29
  30 interval=$1
  31
  32 xs_ipaddr_path="guest/ipv4/0/address"
  33 xs_link_path="guest/ipv4/default-link"
  34 link=""
  35
  36 #
  37 # Look for a valid-seeming address for the given link. Return 0 on success.
  38 #
  39 link_to_addr()
  40 {
  41         tmp=`netstat -I $1 -in -f inet | awk '{print $4}' | grep -v Address`;
  42         if [ -z "$tmp" ] || [ "$tmp" = "0.0.0.0" ];
  43         then
  44                 addr="(none)";
  45                 return 1;
  46         fi
  47
  48         addr=$tmp;
  49         return 0;
  50 }
  51
  52 default_link()
  53 {
  54         #
  55         # Look in the store for a cached link name.
  56         #
  57         link=`/usr/lib/xen/bin/xenstore-read $xs_link_path 2>/dev/null`
  58         if [ -z "$link" ] || [ "$link" = "(none)" ]
  59         then
  60                 #
  61                 # If it's not there, try to determine what it is
  62                 # and add it to the store.
  63                 determine_default_link
  64         fi
  65 }
  66
  67 #
  68 # Determine the default link name and update xenstore with the details.
  69 #
  70 determine_default_link()
  71 {
  72         link="(none)";
  73         #
  74         # Choose the first up, non-loopback interface with a valid-looking
  75         # IP address.
  76         #
  77         dladm show-link -p -o link,state | while IFS=: read LINKNAME STATE;
  78         do
  79                 if [ "$STATE" = "up" ];
  80                 then
  81                         link_to_addr "$LINKNAME"
  82                         if [ $? -eq 0 ]; then link=$LINKNAME; break; fi
  83                 fi
  84
  85         done
  86
  87         /usr/lib/xen/bin/xenstore-write $xs_link_path $link
  88 }
  89
  90 while true; do
  91
  92         #
  93         # Determine the default link in use by this domU.
  94         #
  95         default_link;
  96
  97         #
  98         # If the link still has a valid-looking IP address, notify dom0 of its
  99         # address.
 100         #
 101         link_to_addr $link
 102         if [ $? -ne 0 ]
 103         then
 104                 #
 105                 # An address could not be determined for the currently cached
 106                 # default link so determine it again in case it has changed.
 107                 # We'll still sleep this iteration to rate-limit dladm calls.
 108                 #
 109                 determine_default_link;
 110         fi
 111
 112         /usr/lib/xen/bin/xenstore-write $xs_ipaddr_path $addr
 113
 114         sleep $interval
 115 done
 116