iankelling.org Git - automated-distro-installer/blob - pxe-server

   1 #!/bin/bash
   2 # Copyright (C) 2016 Ian Kelling
   3
   4 # This program is free software; you can redistribute it and/or
   5 # modify it under the terms of the GNU General Public License
   6 # as published by the Free Software Foundation; either version 2
   7 # of the License, or (at your option) any later version.
   8
   9 # This program is distributed in the hope that it will be useful,
  10 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 # GNU General Public License for more details.
  13
  14 # You should have received a copy of the GNU General Public License
  15 # along with this program; if not, write to the Free Software
  16 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  17
  18
  19 [[ $EUID == 0 ]] || exec sudo -E "${BASH_SOURCE[0]}" "$@"
  20
  21 x="$(readlink -f "$BASH_SOURCE")"; source "${x%/*}/bash-trace"
  22
  23
  24 usage() {
  25   cat <<EOF
  26 Usage: ${0##*/} [OPTIONS] [HOST] [TYPE]
  27 Configure dnsmasq boot options and fai-chboot if appropriate. This is
  28 not general purpose, it has code specific to dhcp servers I run.
  29
  30 Without TYPE, disable  server and fai server. In that case, HOST is only
  31 needed for fsf office network.
  32
  33 HOST       A hostname known to the dhcp server, or default for all.
  34 TYPE       One of arch, parabola, plain, fai.
  35
  36 -a         Don't setup pxe, just Wait for 2 dhcp acks, then disable the pxe
  37            server after a delay.  First ack is for pxe boot, 2nd ack is
  38            for os boot. Sometimes on debian, there is a 3rd one shortly
  39            after the 2nd. I can't remember exactly why this caused a
  40            problem, but I'm hoping the sleep will take care of it.
  41 -d         Don't alter dhcp config. Only make sense for fai type, and on network
  42            other than home or fsf.
  43 -k         Pass -k to myfai-chboot.
  44 -r         Don't redeploy fai config. For example, if there is a different host
  45            that is mid-install.
  46
  47 -S         sets FAI_ACTION=sysinfo, see myfai-chboot for more info.
  48 -w         Setup pxe, then wait like -a.
  49 -h|--help  Print help and exit
  50
  51
  52 Note, when switching between plain and arch or parabola, you will need to
  53 do something like:
  54 ssh wrt
  55 cd /mnt/usb
  56 rm tftpboot
  57 ln -s <arch/parabola/debian iso dir> tftpboot
  58
  59
  60 Notes on debugging pxe dhcp tftp:
  61
  62 For debugging dhcp, add to /etc/dnsmasq.conf: log-dhcp
  63
  64 Newer openwrt runs dnsmasq with a whitelist of readable files and dirs:
  65
  66 ps ww :
  67 /sbin/ujail -t 5 -n dnsmasq -u -l -r /bin/ubus -r /etc/TZ -r /etc/dnsmasq.conf -r /etc/ethers -r /etc/group -r /etc/hosts -r /etc/passwd -w /tmp/dhcp.leases -r /tmp/dnsmasq.d -r /tmp/hosts -r /tmp/resolv.conf.d -r /usr/bin/jshn -r /usr/lib/dnsmasq/dhcp-script.sh -r /usr/share/dnsmasq/dhcpbogushostname.conf -r /usr/share/dnsmasq/rfc6761.conf -r /usr/share/dnsmasq/trust-anchors.conf -r /usr/share/libubox/jshn.sh -r /var/etc/dnsmasq.conf.cfg01411c -w /var/run/dnsmasq/ -- /usr/sbin/dnsmasq -C /var/etc/dnsmasq.conf.cfg01411c -k -x /var/run/dnsmasq/dnsmasq.cfg01411c.pid
  68
  69 logging tftp requests:
  70 /etc/default/tftpd-hpa:
  71 add -vv:
  72 TFTP_OPTIONS="--secure -vv"
  73 jr -u tftpd-hpa -f
  74
  75 Note: Uses GNU getopt options parsing style
  76 EOF
  77   exit $1
  78 }
  79
  80 pre="${0##*/}:"
  81 m() { printf "$pre %s\n"  "$*"; "$@"; }
  82 e() { printf "$pre %s\n"  "$*"; }
  83 err() { echo "[$(date +'%Y-%m-%d %H:%M:%S%z')]: $pre: $*" >&2; }
  84
  85 PATH="/a/exe:$PATH"
  86
  87 ##### begin command line parsing ########
  88
  89 dhcp=true
  90 redep=true
  91 acks=2
  92 wait=false
  93 fsf=false
  94
  95 case $HOSTNAME in
  96   x3|kw) fsf=true ;;
  97 esac
  98
  99 chboot_args=()
 100 temp=$(getopt -l help adkrSwh "$@") || usage 1
 101 eval set -- "$temp"
 102 while true; do
 103   case $1 in
 104     -a) wait=true; set=false; shift ;;
 105     -d) dhcp=false; shift ;;
 106     -k) chboot_args+=(-k); shift ;;
 107     -r) redep=false; shift ;;
 108     -S) chboot_args+=(-S); shift ;;
 109     -w) wait=true; set=true; shift ;;
 110     -h|--help) usage ;;
 111     --) shift; break ;;
 112     *) echo "$0: Internal error!" ; exit 1 ;;
 113   esac
 114 done
 115
 116 read -r host type <<<"$@"
 117
 118 case $# in
 119   [01]);;
 120   2)
 121     case $type in
 122       arch|parabola) cmd=archlike ;;
 123       fai) cmd=fai ;;
 124       *)
 125         echo "$0: error expected type of arch|parabola|fai"
 126         echo
 127         usage 1
 128         ;;
 129     esac
 130     ;;
 131   *)
 132     echo "$0: error: expected 0-2 arguments"
 133     echo
 134     usage 1
 135     ;;
 136 esac
 137
 138
 139 if $wait && ! $dhcp; then
 140   echo "$0: error -w conflicts with -d, choose one or other"
 141   exit 1
 142 fi
 143
 144
 145 if [[ $host && $host != default ]]; then
 146   host_tag="tag:$host,"
 147 fi
 148
 149 ##### end command line parsing ########
 150
 151 archlike() {
 152   cat <<EOF
 153 ${host_tag}209,boot/syslinux/${type}iso.cfg
 154 ${host_tag}210,/${type}/
 155 ${host_tag}option:bootfile-name,/${type}/boot/syslinux/lpxelinux.0
 156 EOF
 157 }
 158
 159 plain() {
 160   # if arch based was used before, this additionally needs
 161   # the tftp link in /mnt/usb to be changed.
 162   cat <<EOF
 163 ${host_tag}option:bootfile-name,pxelinux.0
 164 EOF
 165 }
 166
 167 fai() {
 168   cat <<EOF
 169 ${host_tag}option:bootfile-name,pxelinux.0
 170 ${host_tag}option:server-ip-address,$faiserverip
 171 ${host_tag}option:tftp-server,$faiserverip
 172 EOF
 173   # Note, previously used normal dnsmasq option, but it requires dnsmasq
 174   # restart, which causes momentary dns failures, which can bork an
 175   # install.
 176   #
 177   # dhcp-boot=${host_tag}pxelinux.0,faiserver.b8.nz,faiserver.b8.nz
 178 }
 179
 180 ack-wait() {
 181   if $fsf; then
 182     wait_cmd="ssh tarantula.office.fsf.org tail -n0 -f /var/log/syslog"
 183   else
 184     wait_cmd="ssh cmc logread -f"
 185   fi
 186   wait_count=$1
 187   if [[ $host ]]; then
 188     if $fsf; then
 189       host_regex=" $(getent hosts kw | awk '{print $1}' | sed 's/\./\\./g')"
 190     else
 191       host_regex=" $host"
 192     fi
 193   fi
 194   regex=".*DHCPACK.*$host_regex\b"
 195   i=0
 196   while (( i != wait_count )) && read -r line; do
 197     if [[ $line =~ $regex ]]; then
 198       i=$((i+1))
 199       echo $line
 200     fi
 201   done < <($wait_cmd ||:) # tail returns 2 it seems
 202   m sleep 20
 203 }
 204
 205 set-pxe() {
 206   $dhcp || return 0
 207   if $fsf; then
 208     if [[ ! $cmd ]]; then
 209       e "removing pxe for $host on tarantula"
 210       ssh tarantula.office.fsf.org bash -e <<EOF
 211 sed -ri 's/^( *host +$host *\{).*/\1/' /etc/dhcp/dhcpd.conf
 212 systemctl restart isc-dhcp-server
 213 EOF
 214     elif [[ $cmd == fai ]]; then
 215       e "adding pxe for $host on tarantula"
 216       ssh tarantula.office.fsf.org bash -e <<EOF
 217 sed -ri 's/^( *host +$host *\{).*/\1 next-server faiserver.office.fsf.org; filename "pxelinux.0";/' /etc/dhcp/dhcpd.conf
 218 systemctl restart isc-dhcp-server
 219 EOF
 220     fi
 221   else
 222     e "updating dnsmasq.conf:"
 223     m $cmd
 224     ${cmd:-:}|ssh cmc "dd of=/var/run/dnsmasq/dhcpopts.conf; /etc/init.d/dnsmasq reload
 225 $([[ $type == arch || $type == parabola ]] && echo archlike-pxe-mount)"
 226   fi
 227 }
 228
 229 type -t host &>/dev/null || sudo apt-get -y install dnsutils
 230 faiserverip=$(host faiserver | sed -rn 's/^\S+ has address //p;T;q' ||:)
 231 if [[ ! $faiserverip || $faiserverip =~ [[:space:]] ]]; then
 232   echo "$0: error: failed to get \$faiserverip, got: $faiserverip"
 233   exit 1
 234 fi
 235
 236
 237 if $set; then
 238   set-pxe
 239   if [[ $type == fai ]]; then
 240     if $redep; then
 241       m fai-redep
 242     fi
 243     m myfai-chboot ${chboot_args[@]} $host
 244   else
 245     # This will fail if faiserver is not setup, so ignore any
 246     # failure and don't bother us about it.
 247     myfai-chboot &>/dev/null ||:
 248   fi
 249 fi
 250
 251 if $wait; then
 252   # fai's debian jessie 8.5ish does 2 dhcp requests when booting,
 253   # roughly 4 seconds apart. Earlier
 254   # versions did just 1. Now testing on a vm, it does 1.
 255   # bleh.
 256   echo "waiting for $acks dhcp acks then disabling pxe"
 257   ack-wait $acks
 258   type=
 259   unset cmd
 260   set-pxe
 261
 262   # previously tried waiting for one more ack then disabling faiserver,
 263   # since it can contain sensitive info, so turn it off when not in use,
 264   # but disabling that for now as it's inconvenient to clean this
 265   # up and run it in the background etc.
 266
 267   # if [[ $type == fai ]]; then
 268   #     echo "waiting for 1 dhcp ack then disabling fai server"
 269   #     ack-wait 1
 270   #     faiserver-disable
 271   # fi
 272 fi