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 "$file"
  20                 return
  21         fi
  22
  23         # Otherwise, TFTP using an appropriate host. Start with the
  24         # DHCP 'tftp' option:
  25         host=${tftp}
  26
  27         # next, try the DHCP next-server-address
  28         [ -z "$host" ] && host=${siaddr}
  29
  30         # finally, use the DHCP server we got this lease from:
  31         [ -z "$host" ] && host=${serverid}
  32
  33         echo "tftp://$host/$file"
  34 }
  35
  36 do_pxe() {
  37         basedir=$1
  38
  39         params="conf@${interface} method=dhcp"
  40
  41         # first, try by MAC
  42         mac=$(tr ':' '-' < /sys/class/$interface/address)
  43         pb-event $params url=$basedir/01-$mac
  44
  45         # try decreasing fragments of IP lease
  46         ip_hex=$(printf '%02X%02X%02X%02X' $(echo $ip | tr '.' ' '))
  47         for i in $(seq 8 -1 1)
  48         do
  49                 frag=${ip_hex:0:$i}
  50                 pb-event $params url=$basedir/$frag
  51         done
  52
  53         # last, use default
  54         pb-event $params url=$basedir/default
  55 }
  56
  57 pb_add () {
  58
  59         # Look for an explicit config file location in the DHCP config-file
  60         # parameter
  61         if [ -n "${conffile}" ]
  62         then
  63                 url=$(resolve_url ${conffile})
  64                 pb-event conf@${interface} url=$url method=dhcp
  65                 return
  66         fi
  67
  68         # Otherwise, we'll need the boot-file parameter. Looks like udhcpc
  69         # will give us different names, depending if the parameter was in
  70         # the header, or specified by options
  71         [ -z "$bootfile" ] && bootfile=${boot_file}
  72
  73         if [ -z "$bootfile" ]
  74         then
  75                 return
  76         fi
  77
  78         # PXE behaviour is to download the config file based on a file
  79         # structure relative to the pxelinux binary
  80         file=${bootfile}
  81         [ -z "$file" ] && file=${boot_file}
  82         if [ -n "$file" ]
  83         then
  84                 basedir=${file%%/*}
  85                 do_pxe $basedir
  86         fi
  87
  88         # Finally, add an option for the boot_file parameter
  89         k_server_ip=${rootpath%%:*}
  90         k_root_dir=${rootpath#*:}
  91
  92         args=
  93         if [ -n "$rootpath" ]
  94         then
  95                 [ ${k_server_ip} != ${rootpath} ] || k_server_ip=${serverid}
  96                 args="root=/dev/nfs ip=any nfsroot=${k_server_ip}:${k_root_dir}"
  97         fi
  98
  99         pb-event add@${interface} \
 100                 name=netboot \
 101                 image=tftp://${siaddr}/${boot_file} \
 102                 args="$args"
 103 }
 104
 105 pb_remove () {
 106         pb-event remove@${interface} name=netboot
 107 }
 108
 109 case "$1" in
 110 bound)
 111         pb_add
 112         ;;
 113 deconfig)
 114         pb_remove
 115         ;;
 116 *)
 117         ;;
 118 esac
 119
 120 printf "--- $1 ---\n" >> ${log}
 121 set >> ${log}
 122 printf "---------------\n" >> ${log}