#!/bin/bash
# Copyright (C) 2018 Ian Kelling

# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.

# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.

# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

x="$(readlink -f "$BASH_SOURCE")"; source "${x%/*}/bash-trace"

[[ $EUID == 0 ]] || exec sudo "${BASH_SOURCE}" "$@"

usage() {
  cat <<EOF
usage: ${0##*/} [-h|--help]
install fai-server on the current machine

Initial setup of a fai server on debian. works on localhost.
Set's the current ip as the tftp server. I vaguely remember
that using a hostname does not work.
Separate from running this, faiserver needs to be setup in dns
to point to whatever host this is run on.

It expects $BASEFILE_DIR/STRETCH64.tar.gz to exist.

EOF
  exit $1
}
case $1 in
  -h|--help) usage ;;
esac


e() { echo "$@"; "$@"; }

# the automatic basefile getting will be for stretch
# instead of jessie, so if you install jessie, you need
# to setup the basefile and it\'s corresponding class.
base=stretch
sed="sed -ri --follow-symlinks"

if ! type -p wget &>/dev/null; then
  apt-get install -y wget
fi

armhf() {
  [[ $(dpkg --print-architecture) == armhf ]]
}

if armhf; then
  if apt-cache policy | grep o=Debian,a=testing,n=stretch &>/dev/null; then
    cat >/etc/apt/sources.list.d/testing.list <<'EOF'
deb http://http.us.debian.org/debian testing main contrib non-free
deb-src http://http.us.debian.org/debian testing main contrib non-free

deb http://security.debian.org/ testing/updates main contrib non-free
deb-src http://security.debian.org/ testing/updates main contrib non-free

deb http://http.us.debian.org/debian testing-updates main contrib non-free
deb-src http://http.us.debian.org/debian testing-updates main contrib non-free
EOF

    cat >/etc/apt/preferences.d/fai <<'EOF'
Package: fai-server fai-client fai-doc
Pin: release a=testing
Pin-Priority: 500

Package: *
Pin: release a=testing
Pin-Priority: -10
EOF
  fi
elif grep -xFq 'VERSION="8 (jessie)"' /etc/os-release; then
  gpg -a --recv-keys 2BF8D9FE074BCDE4; gpg -a --export 2BF8D9FE074BCDE4 | apt-key add -
  cat >/etc/apt/sources.list.d/fai.list <<'EOF'
deb http://fai-project.org/download jessie koeln
EOF
elif grep -xFq 'VERSION="9 (stretch)"' /etc/os-release || grep -iE 'flidas|xenail' /etc/os-release ; then
  # fai on ubuntu only has official support using the universe repo, but newer
  # tends to have less bugs.
  gpg --keyserver hkp://pool.sks-keyservers.net -a --recv-keys 2BF8D9FE074BCDE4; gpg -a --export 2BF8D9FE074BCDE4 | apt-key add -

  cat >/etc/apt/sources.list.d/fai.list <<'EOF'
deb http://fai-project.org/download stretch koeln
EOF
else
  rm -f /etc/apt/sources.list.d/fai.list
fi

apt-get update

# Relevant packages from fai-quickstart depends and fai-server recommends.
# I especially do not wait isc-dhcp-server or an inetd. Also excludes
# nfs-kernel-server. On an android chroot, we don\'t have nfs in the
# kernel, or the ability to install it.
# xorriso is for running fai-cd -a, not strictly need for fai-server
# perl-tk is for fai-monitor-gui
pkgs=(fai-doc tftpd-hpa tar reprepro squashfs-tools binutils xorriso)
if modprobe nfsd &>/dev/null; then
  pkgs+=(nfs-kernel-server)
else
  pkgs+=(apache2)
fi


apt-get install -y ${pkgs[@]}
# confnew since we edit /etc/fai/NFSROOT in an automated way
# fai-client is already a fai-server dependency, but make sure it gets upgraded
apt-get install --no-install-recommends -y -o Dpkg::Options::="--force-confnew" fai-server fai-client

r=http://http.us.debian.org/debian
# like default, but scrap httpredir, and nonfree.
# All my systems should be able to get along without nonfree
# for a base working system afaik.
cat >/etc/fai/apt/sources.list <<EOF
deb $r $base main contrib
deb http://security.debian.org/debian-security $base/updates main contrib
EOF


case $base in
  jessie|stretch)
    cat >>/etc/fai/apt/sources.list <<EOF
# use fai repo. it's commented in the defaults. it's got bug fixes.
# and may contain newer packages.
deb http://fai-project.org/download $base koeln
EOF
    ;;
esac

if [[ $base == jessie ]]; then
  cat >>/etc/fai/apt/sources.list <<'EOF'
# fix tar https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=819978
deb http://ftp.debian.org/debian jessie-backports main
EOF
  # note, fai doesn\'t look at /etc/fai/apt/preferences.d
  cat >/etc/fai/apt/preferences <<'EOF'
Package: tar
Pin: release a=jessie-backports
Pin-Priority: 500
EOF
fi


# tried out a stretch base, doesn't work yet.
#
$sed -f - /etc/fai/nfsroot.conf <<EOF
$ a FAI_ROOTPW='$(</q/root/shadow/standard)'
/^\s*FAI_ROOTPW/d
$ a SSH_IDENTITY=/root/.ssh/home.pub
/^\s*SSH_IDENTITY/d
s,^( *FAI_DEBOOTSTRAP=).*,\1"$base $r",
# add --arch amd64. this is needed on arm system which is
# used to install amd64 clients. On amd64 servers, it's redundant.
# disabled for now, since creating fai nfsroot on my arm machine
# is not working
#/--arch amd64/!s/^(\s*FAI_DEBOOTSTRAP_OPTS=")/\1--arch amd64 /
EOF

$sed 's/#LOGUSER/LOGUSER/' /etc/fai/fai.conf
$sed -i '/^FAI_FLAGS=/d' /etc/fai/fai.conf
echo "FAI_FLAGS=verbose" >>/etc/fai/fai.conf

# from man fai-make-nfsroot,
# figured out after partitioning ignored my crypt partition


if ! grep cryptsetup /etc/fai/NFSROOT &>/dev/null; then
  cat >>/etc/fai/NFSROOT <<'EOF'
# inserted by faserver-setup
PACKAGES install
cryptsetup
EOF
fi

if armhf; then
  cd /srv/fai
  rm -rf nfsroot
  tar Jxf $BASEFILE_DIR/STRETCH64.tar.xz
  # background: Can't build the nfsroot on my arm system now.  First,
  # fai-make-nfsroot won't work out of the box. One idea to make it work
  # is by installing qemu-user-static, then copying qemu-x86_64-static
  # into the nfsroot, and prepending it to chroot commands in
  # fai-make-nfsroot, but that fails in odd ways. ls has permissions
  # problems on reading directories, various programs segfault
  # immediately, cat can't open a file, etc.

  NFSROOT=/srv/fai/nfsroot
  TFTPROOT=/srv/tftp/fai

  # test if our copy of setup_tftp has changed in fai-make-nfsroot,
  # and if not, run it.
  setup_tftp(){

    # tftp environment
    local pxebin

    # wheezy path
    if [ -f $NFSROOT/usr/lib/PXELINUX/pxelinux.0 ]; then
      pxebin=$NFSROOT/usr/lib/PXELINUX/pxelinux.0
    else
      # jessie/stretch path
      pxebin=$NFSROOT/usr/lib/syslinux/pxelinux.0
    fi

    rm -f $NFSROOT/boot/*.bak
    mkdir -p $TFTPROOT/pxelinux.cfg
    if ! chmod a+r $NFSROOT/boot/initrd.img-*; then
      echo "$0: error: No initrd was created. Check the package name of the linux-image package in /etc/fai/NFSROOT."
      exit 1
    fi
    cp -p $v $NFSROOT/boot/vmlinu?-* $NFSROOT/boot/initrd.img-* $TFTPROOT
    cp -u $pxebin $TFTPROOT
    if [ -f $NFSROOT/usr/lib/syslinux/modules/bios/ldlinux.c32 ]; then
      cp -u $NFSROOT/usr/lib/syslinux/modules/bios/ldlinux.c32 $TFTPROOT
    fi
    if [ X$verbose = X1 ]; then
      echo "TFTP environment prepared. Enable DHCP and start the TFTP daemon on root $TFTPROOT."
    fi
  }
  diff -u <(type setup_tftp) <(cat <(sed -n '/^setup_tftp(){/,/^}/p' $(which fai-make-nfsroot) ) - <<'EOF' |bash
type setup_tftp
EOF
                              )
  setup_tftp

  # -g causes skipping set_root_pw() in fai-make-nfsroot, -ag
  # is the only way to make it run without chrooting. the options
  # seem contradictory, but it works.
  fai-setup -evag

else # not armhf
  # note, this copies the -B arg to
  # /srv/fai/nfsroot/var/tmp/base.tar.xz
  e fai-setup -evf -B $BASEFILE_DIR/STRETCH64.tar.gz
  # fai-setup expert mode avoids writing to /var/log/fai/variables
  # at least config_src is needed for autodiscover
  $sed '/^FAI_CONFIGDIR|^FAI_CONFIG_SRC|^LOGUSER/d' /var/log/fai/variables
  tee -a /var/log/fai/variables <<'EOF'
LOGUSER=fai
FAI_CONFIGDIR=/srv/fai/config
FAI_CONFIG_SRC=nfs://faiserver/srv/fai/config
EOF
  # make the faiserver also the apt proxy server
  apt-get -y install apt-cacher-ng
fi

rm -f /srv/fai/nfsroot/root/.ssh/known_hosts
key=$(ssh-keyscan localhost |& grep -o "ecdsa-sha2-nistp256.*")
for ip in faiserver $(ip addr show up| grep -w '^ *inet' | awk '{print $2}'| cut -d / -f 1 | grep -vF 127.0.0.1); do
  echo "$ip $key" >>/srv/fai/nfsroot/root/.ssh/known_hosts
done


# serial console
# mainly from
# https://wiki.archlinux.org/index.php/working_with_the_serial_console
# at runtime, running this from ssh worked:
# https://unix.stackexchange.com/questions/242778/what-is-the-easiest-way-to-configure-serial-port-on-linux
# stty -F /dev/ttyS0 115200 cs8 -cstopb -parenb
# /sbin/agetty 115200 ttyS0 linux
# dated info, but validation that this might work on debian:
# https://help.ubuntu.com/community/SerialConsoleHowto
# note in the nfsroot, systemd is not running.
echo "c0:2345:respawn:/sbin/agetty 115200 ttyS0 linux" >>/srv/fai/nfsroot/etc/inittab

# initially did the basic fai-chboot -Iv $std_arg default
# but found in console that it wanted to mount nfsroot
# to be the same as my dhcp server.
# Figured out to change the root= parameter from googling,
# and seeing fai-chboot -L
# using hostname failed.
# for -f, combined the 2 defaults so it will reboot and print to screen.

# Add debug to -f flag for more verbose output.


# background on choosing apt-cacher-ng:
# googling around a bit finds 2 main solutions:
# http://askubuntu.com/questions/3503/best-way-to-cache-apt-downloads-on-a-lan
# apt-cacher-ng doesn\'t have zeroconf.
# It touts having minimal dependencies, but I don\'t care.
# The downside to squid-deb-proxy is that it\'s config is for specific repos,
# you have to add all the repos you use.
# That is the main reason I use apt-cacher-ng.
# It has a web portal, at http://faiserver:3142/acng-report.html


# random fai note: as far as I can tell, profiles are just for putting
# in a selectable boot menu, which I don\'t want.

# the logsave prompted because the hostname faiserver was uknown.
# Here it was faiserver.lan when running from a faiserver vm.
# When running from a normal host with faiserver alias, it was the normal hosts name.
$sed 's/(^[^,]+,)\S+/\1faiserver/' /srv/fai/nfsroot/root/.ssh/known_hosts
# ditch the logo banner up top which screws with less.
touch /srv/fai/nfsroot/.nocolorlogo