git.ozlabs.org Git - petitboot/blob - utils/pb-udhcpc

   1 #!/bin/sh
   2 #
   3 # Petitboot udhcpc user script.  Should be run by udhcpc when
   4 # there is a change in the dhcp configuration.  For more info
   5 # see the udhcpc man page and the Linux kernel source file
   6 # Documentation/filesystems/nfsroot.txt.
   7 #
   8
   9 PBOOT_USER_EVENT_SOCKET="/tmp/petitboot.ev"
  10 log="/var/log/petitboot/pb-udhcpc.log"
  11
  12 resolve_url() {
  13         file="$1"
  14
  15         # URL? use as-is.
  16         tmp=${file#://*}
  17         if [ "$tmp" != "$file" ]
  18         then
  19                 echo "$file"
  20         fi
  21
  22         # Otherwise, TFTP using an appropriate host. Start with the
  23         # DHCP 'tftp' option:
  24         host=${tftp}
  25
  26         # next, try the DHCP next-server-address
  27         [ -z "$host" ] && host=${siaddr}
  28
  29         # finally, use the DHCP server we got this lease from:
  30         [ -z "$host" ] && host=${serverid}
  31
  32         echo "tftp://$host/$file"
  33 }
  34
  35 do_pxe() {
  36         basedir=$1
  37
  38         params="conf@/net/${interface} method=dhcp"
  39
  40         # first, try by MAC
  41         mac=$(cat /sys/class/net/$interface/address)
  42         pb-event $params url=$basedir/$mac
  43
  44         # try decreasing fragments of IP lease
  45         ip_hex=$(printf '%02X%02X%02X%02X' $(echo $ip | tr '.' ' '))
  46         for i in $(seq 8 -1 1)
  47         do
  48                 frag=${hex_ip:0:$i}
  49                 pb-event $params url=$basedir/$frag
  50         done
  51
  52         # last, use default
  53         pb-event $params url=$basedir/default
  54 }
  55
  56 pb_add () {
  57
  58         # Look for an explicit config file location in the DHCP config-file
  59         # parameter
  60         if [ -n ${conffile} ]
  61         then
  62                 url=$(resolve_url ${conffile})
  63                 pb-event conf@/net/${interface} url=$url method=dhcp
  64                 return
  65         fi
  66
  67         # Otherwise, we'll need the boot-file parameter. Looks like udhcpc
  68         # will give us different names, depending if the parameter was in
  69         # the header, or specified by options
  70         [ -n "$bootfile" ] && bootfile=${boot_file}
  71
  72         if [ -z "$bootfile" ]
  73         then
  74                 return
  75         fi
  76
  77         # PXE behaviour is to download the config file based on a file
  78         # structure relative to the pxelinux binary
  79         file=${bootfile}
  80         [ -z "$file" ] && file=${boot_file}
  81         if [ -n "$file" ]
  82         then
  83                 basedir=${file%%/*}
  84                 do_pxe $basedir
  85         fi
  86
  87         # Finally, add an option for the boot_file parameter
  88         k_server_ip=${rootpath%%:*}
  89         k_root_dir=${rootpath#*:}
  90
  91         args=
  92         if [ -n $rootpath ]
  93         then
  94                 [ ${k_server_ip} != ${rootpath} ] || k_server_ip=${serverid}
  95                 args="root=/dev/nfs ip=any nfsroot=${k_server_ip}:${k_root_dir}"
  96         fi
  97
  98         pb-event add@/net/${interface} \
  99                 name=netboot \
 100                 image=tftp://${siaddr}/${boot_file} \
 101                 args="$args"
 102 }
 103
 104 pb_remove () {
 105         pb-event remove@/net/${interface} name=netboot
 106 }
 107
 108 case "$1" in
 109 bound | renew)
 110         pb_add
 111         ;;
 112 deconfig)
 113         pb_remove
 114         ;;
 115 *)
 116         ;;
 117 esac
 118
 119 printf "--- $1 ---\n" >> ${log}
 120 set >> ${log}
 121 printf "---------------\n" >> ${log}