#!/bin/bash
#
# System installer.
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as
# published by the Free Software Foundation, either version 3 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 Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public
# License along with this program.  If not, see
# <http://www.gnu.org/licenses/>.

# Load.
source $APP_BASE/lib/hydra/functions || exit 1
hydra_config_load

# Create a logical volume.
function hydra_provision_lvcreate {
  local volume="$1"
  local size="$2"
  local space

  if [ -z "$volume" ] || [ "$size" == "0" ]; then
    return
  fi

  if ! lvdisplay $vg/$volume &> /dev/null; then
    echo "Creating logical volume $volume..."
    if [ "$size" == "-1" ]; then
      space="-l 100%FREE"
    else
      space="-L $size"
    fi

    # See http://forums.funtoo.org/viewtopic.php?id=1206
    #     https://bbs.archlinux.org/viewtopic.php?id=124615
    if [ "$disable_zeroing" == "y" ]; then
      hydra_sudo_run lvcreate -Z n $space -n $volume $vg
    else
      hydra_sudo_run lvcreate $space -n $volume $vg
    fi
  fi
}

# Cryptsetup wrapper.
function hydra_cryptsetup {
  if [ ! -z "$1" ] && [ -b "$1" ]; then
    hydra_sudo_run cryptsetup --cipher aes-xts-plain64:sha256 --key-size 512 --hash sha512 --iter-time 5000 --use-random -y -q luksFormat $1
  fi
}

# Create a physical volume.
function hydra_provision_create_volume {
  local volume="$1"

  if [ -z "$volume" ] || [ ! -b "/dev/mapper/$vg-$volume" ]; then
    return
  fi

  if [ "$encrypt" == "y" ]; then
    echo "Creating encrypted $volume device..."
    hydra_cryptsetup /dev/mapper/$vg-$volume
    hydra_sudo_run cryptsetup luksOpen /dev/mapper/$vg-$volume provision-$volume
    hydra_sudo_run mkfs.ext4 /dev/mapper/provision-$volume

    if [ "$volume" == "root" ]; then
      install_device="/dev/mapper/provision-root"
    fi
  else
    echo "Creating $volume device..."
    hydra_sudo_run mkfs.ext4 /dev/mapper/$vg-$volume

    if [ "$volume" == "root" ]; then
      install_device="/dev/mapper/$vg-root"
    fi
  fi
}

# Make sure there is provision config.
function hydra_provision_config {
  local base_arch="`uname -m`"

  if [ "$base_arch" == "x86_64" ]; then
    base_arch="amd64"
  else
    base_arch="i386"
  fi

  hydra_user_config   interactive       y                                "Interactive mode? (y/n)"
  hydra_user_config   device            /dev/sdb                         "Destination device"
  hydra_user_config   swap_size         2000                             "Swap size (in MB, 0 to not create it)"
  hydra_user_config   root_size         20G                              "Size of root partition (-1 for all free space)"
  hydra_user_config   home_size         20G                              "Size of home partition (0 to not create it, -1 for all free space)"
  hydra_user_config   var_size          20G                              "Size of var partition  (0 to not create it, -1 for all free space)"
  hydra_user_config   encrypt           y                                "Encrypt volumes? (y/n)"
  hydra_user_config   garbage           y                                "Pre-fill volumes with garbage? (y/n)"
  hydra_user_config   random_swap       y                                "Random swap? (y/n)"
  hydra_user_config   disable_zeroing   n                                "Disable zeroing of LVM volumes? (y/n)"
  hydra_user_config   hostname          machine                          "Hostname"
  hydra_user_config   domain            example.org                      "Domain"
  hydra_user_config   arch              $base_arch                       "System arch"
  hydra_user_config   version           jessie                           "Distro version"
  hydra_user_config   vg                $hostname                        "Install vg"
  hydra_user_config   grub              y                                "Setup GRUB? (y/n)"
  hydra_user_config   mirror            http://http.debian.net/debian/   "Debian mirror"

  # Check arch
  if [ "$arch" == "armel" ] || [ "$arch" == "armhf" ]; then
    echo "You probably want to run provision-raspi instead of provision"
    exit 1
  fi
}

# Load configuration
hydra_provision_config_load $1

# Parameters
WORK="/tmp/debootstrap"

# Set environment
export LC_ALL=C

# Get config parameters.
hydra_provision_config

# Check for requirements.
for req in debootstrap cryptsetup grub-pc lvm2 parted mdadm; do
  hydra_install_package $req
done

# Warning.
if [ "$interactive" == "y" ]; then
  echo "WARNING: about to create partitions on $device!"
  echo "WARNING: make sure you have backups of the important data from this device!"
  echo "Press ENTER to continue, Ctrl-C to abort."
  read answer
fi

# Disk partitioning.
hydra_sudo_run parted -s -- $device mklabel gpt
hydra_sudo_run parted -s -- $device unit MB mkpart non-fs 2    3
hydra_sudo_run parted -s -- $device set 1 bios_grub on

if [ "$encrypt" == "y" ]; then
  hydra_sudo_run parted -s -- $device unit MB mkpart ext2   3    -1
  hydra_sudo_run parted -s -- $device set 2 lvm  on

  boot_device="$device"2
  syst_device="$device"2
else
  hydra_sudo_run parted -s -- $device unit MB mkpart ext2   3    200
  hydra_sudo_run parted -s -- $device unit MB mkpart ext2   200  -1
  hydra_sudo_run parted -s -- $device set 3 lvm  on

  boot_device="$device"2
  syst_device="$device"3

  # Use absolute path
  reboot_device="`blkid | grep ^$boot_device: | cut -d ' ' -f 2 | sed -e 's/"//g'`"
fi

hydra_sudo_run parted -s -- $device set 2 boot on

# Create volumes.
echo "Creating the needed disk volumes..."

if ! pvdisplay $syst_device &> /dev/null; then
  echo "Creating physical volume..."
  hydra_sudo_run pvcreate $syst_device
fi

if ! vgdisplay $vg &> /dev/null; then
  echo "Creating volume group..."
  hydra_sudo_run vgcreate $vg $syst_device
fi

# Activate volume group
hydra_sudo_run vgchange -a y $vg

# Create swap partition
if [ "$swap_size" != "0" ]; then
  hydra_provision_lvcreate swap $swap_size
fi

# Create root partition.
hydra_provision_lvcreate root $root_size

# Create home partition.
if [ "$home_size" != "0" ]; then
  hydra_provision_lvcreate home $home_size
fi

# Create var partition.
if [ "$var_size" != "0" ]; then
  hydra_provision_lvcreate var  $var_size
fi

# Garbage.
if [ "$garbage" == "y" ]; then
  echo "Filling volumes with garbage..."

  hydra_sudo_run dd if=/dev/urandom of=/dev/mapper/$vg-root

  if [ -b "/dev/mapper/$vg-home" ]; then
    hydra_sudo_run dd if=/dev/urandom of=/dev/mapper/$vg-home
  fi

  if [ -b "/dev/mapper/$vg-var" ]; then
    hydra_sudo_run dd if=/dev/urandom of=/dev/mapper/$vg-var
  fi

  if [ "$swap_size" != "0" ]; then
    hydra_sudo_run dd if=/dev/urandom of=/dev/mapper/$vg-swap
  fi
fi

# Make sure that the mountpoint exists
hydra_sudo_run mkdir -p $WORK

# Setup mountpoint and make sure it's not mounted due to a failed install.
if cat /proc/mounts | cut -d ' ' -f 2 | grep -q "^$WORK$"; then
  hydra_sudo_run umount $WORK

  for folder in proc dev home var boot sys; do
    if cat /proc/mounts | cut -d ' ' -f 2 | grep -q "^$WORK/$folder$"; then
      hydra_sudo_run umount $WORK/$folder
    fi
  done
fi

# Create swap fs.
if [ "$swap_size" != "0" ] && [ "$random_swap" != "y" ]; then
  hydra_cryptsetup                   /dev/mapper/$vg-swap
  hydra_sudo_run cryptsetup luksOpen /dev/mapper/$vg-swap provision-swap
  hydra_sudo_run mkswap              /dev/mapper/provision-swap
fi

# Create root fs
hydra_provision_create_volume root

# Create home fs.
if [ "$home_size" != "0" ]; then
  hydra_provision_create_volume home
fi

# Create var fs.
if [ "$var_size" != "0" ]; then
  hydra_provision_create_volume var
fi

# Mount root volume.
hydra_sudo_run mount $install_device $WORK/

# Mount additional volumes.
if [ "$home_size" != "0" ]; then
  mkdir $WORK/home

  if [ "$encrypt" == "y" ]; then
    hydra_sudo_run mount /dev/mapper/provision-home $WORK/home
  else
    hydra_sudo_run mount /dev/mapper/$vg-home $WORK/home
  fi
fi

if [ "$var_size" != "0" ]; then
  hydra_sudo_run mkdir $WORK/var

  if [ "$encrypt" == "y" ]; then
    hydra_sudo_run mount /dev/mapper/provision-var $WORK/var
  else
    hydra_sudo_run mount /dev/mapper/$vg-var $WORK/var
  fi
fi

# Non-interactive installation
APT_INSTALL="hydra_sudo_run LC_ALL=C DEBIAN_FRONTEND=noninteractive chroot $WORK/ apt-get install"

# Initial system install.
echo "Installing base system..."
hydra_sudo_run LC_ALL=C DEBIAN_FRONTEND=noninteractive debootstrap --arch=$arch $version $WORK/ $mirror

# Initial configuration.
echo "Applying initial configuration..."
hydra_sudo_run mount none -t proc $WORK/proc
hydra_sudo_run mount none -t sysfs $WORK/sys
hydra_sudo_run mount -o bind /dev/ $WORK/dev
echo LANG=C | $SUDO tee $WORK/etc/default/locale > /dev/null

# Resolver configuration.
echo "domain $domain"            | $SUDO tee    $WORK/etc/resolv.conf > /dev/null
echo "search $hostname.$domain"  | $SUDO tee -a $WORK/etc/resolv.conf > /dev/null
grep nameserver /etc/resolv.conf | $SUDO tee -a $WORK/etc/resolv.conf > /dev/null

# Hostname configuration.
echo $hostname.$domain     | $SUDO tee    $WORK/etc/hostname > /dev/null
echo "127.0.0.1 localhost" | $SUDO tee -a $WORK/etc/hosts    > /dev/null

# This ordering is important for facter correctly guess the domain name
echo "127.0.0.1 $hostname.$domain $hostname" | $SUDO tee -a $WORK/etc/hosts > /dev/null

# Invert hostname contents to avoid http://projects.puppetlabs.com/issues/2533
tac $WORK/etc/hosts | $SUDO tee $WORK/etc/hosts.new > /dev/null
hydra_sudo_run mv $WORK/etc/hosts.new $WORK/etc/hosts

# Initial upgrade.
echo "Applying initial upgrades..."
hydra_sudo_run chroot $WORK/ apt-get update
hydra_sudo_run chroot $WORK/ apt-get upgrade -y
$APT_INSTALL locales cryptsetup lvm2 initramfs-tools -y

# Crypttab.
echo "Configuring crypttab..."
echo "# <target name> <source device>   <key file>  <options>" | $SUDO tee $WORK/etc/crypttab > /dev/null

if [ "$encrypt" == "y" ]; then
  cat <<-EOF | $SUDO tee $WORK/etc/crypttab > /dev/null
root            /dev/mapper/$vg-root      none            luks
EOF
fi

if [ "$home_size" != "0" ] && [ "$encrypt" == "y" ]; then
  cat <<-EOF | $SUDO tee -a $WORK/etc/crypttab > /dev/null
home            /dev/mapper/$vg-home      none            luks
EOF
fi

if [ "$var_size" != "0" ] && [ "$encrypt" == "y" ]; then
  cat <<-EOF | $SUDO tee -a $WORK/etc/crypttab > /dev/null
var             /dev/mapper/$vg-var       none            luks
EOF
fi

if [ "$swap_size" != "0" ] && [ "$random_swap" == "y" ]; then
  cat <<-EOF | $SUDO tee -a $WORK/etc/crypttab > /dev/null
swap            /dev/mapper/$vg-swap      /dev/random     swap,cipher=aes-xts-plain64:sha256
EOF
fi

if [ "$swap_size" != "0" ] && [ "$random_swap" != "y" ]; then
  cat <<-EOF | $SUDO tee -a $WORK/etc/crypttab > /dev/null
swap            /dev/mapper/$vg-swap      none        luks,swap
EOF
fi

# Fstab.
echo "Configuring fstab..."
echo "" | $SUDO tee $WORK/etc/fstab > /dev/null
if [ "$swap_size" != "0" ]; then
  cat <<-EOF | $SUDO tee -a $WORK/etc/fstab > /dev/null
/dev/mapper/swap      none           swap  sw                                 0 0
EOF
fi

if [ "$encrypt" == "y" ]; then
  cat <<-EOF | $SUDO tee -a $WORK/etc/fstab > /dev/null
/dev/mapper/root      /              ext4  defaults,errors=remount-ro         0 1
EOF
else
  cat <<-EOF | $SUDO tee -a $WORK/etc/fstab > /dev/null
/dev/mapper/$vg-root   /              ext4  defaults,errors=remount-ro         0 1
EOF
fi

if [ "$home_size" != "0" ]; then
  if [ "$encrypt" == "y" ]; then
  cat <<-EOF | $SUDO tee -a $WORK/etc/fstab > /dev/null
/dev/mapper/home      /home          ext4  defaults,errors=remount-ro         0 2
EOF
  else
  cat <<-EOF | $SUDO tee -a $WORK/etc/fstab > /dev/null
/dev/mapper/$vg-home   /home          ext4  defaults,errors=remount-ro         0 2
EOF
  fi
fi

if [ "$var_size" != "0" ]; then
  if [ "$encrypt" == "y" ]; then
  cat <<-EOF | $SUDO tee -a $WORK/etc/fstab > /dev/null
/dev/mapper/var       /var           ext4  defaults,errors=remount-ro         0 2
EOF
  else
  cat <<-EOF | $SUDO tee -a $WORK/etc/fstab > /dev/null
/dev/mapper/$vg-var    /var           ext4  defaults,errors=remount-ro         0 2
EOF
  fi
fi

# Kernel.
echo "Installing kernel..."
cat <<-EOF | $SUDO tee $WORK/etc/initramfs-tools/modules > /dev/null
dm-mod
dm-crypt
dm-raid
aes
twofish
sha256
EOF

cat <<-EOF | $SUDO tee $WORK/etc/kernel-img.conf > /dev/null
do_initrd = Yes
EOF

if [ "$arch" == "i386" ]; then
  kernel_arch="686"
else
  kernel_arch="$arch"
fi

# Kernel.
$APT_INSTALL linux-image-$kernel_arch -y

# Initramfs.
echo "Creating initramfs..."
hydra_sudo_run chroot $WORK update-initramfs -v -u

# Grub.
if [ "$grub" == "y" ]; then
  if [ "$encrypt" != "y" ]; then
    echo "Boot device setup..."
    hydra_sudo_run mkfs.ext4 $boot_device
    hydra_sudo_run mount $boot_device $WORK/boot
    echo "$reboot_device /boot ext4 defaults,errors=remount-ro 0 2" | $SUDO tee -a $WORK/etc/fstab > /dev/null
  fi

  echo "Setting up GRUB..."
  $APT_INSTALL grub-pc -y

  if [ "$encrypt" == "y" ]; then
    echo ''                                               | $SUDO tee -a $WORK/etc/default/grub > /dev/null
    echo '# Full Disk Encryption Support'                 | $SUDO tee -a $WORK/etc/default/grub > /dev/null
    echo 'GRUB_ENABLE_CRYPTODISK=y'                       | $SUDO tee -a $WORK/etc/default/grub > /dev/null
    echo 'GRUB_PRELOAD_MODULES="lvm cryptodisk mdraid1x"' | $SUDO tee -a $WORK/etc/default/grub > /dev/null
    hydra_sudo_run chroot $WORK/ update-grub
    hydra_sudo_run chroot $WORK/ grub-install --recheck --force $device

    # Fix menu entry
    hydra_sudo_run sed -i -e "s|root=/dev/mapper/provision-root|root=/dev/mapper/root|g" $WORK/boot/grub/grub.cfg
  fi
fi

# Utils.
echo "Installing basic utilities..."
$APT_INSTALL screen cron lsb-release openssl -y

# Networking.
hydra_provision_networking

# Ssh.
echo "Installing OpenSSH daemon..."
$APT_INSTALL openssh-server -y
hydra_sudo_run chroot $WORK/ service ssh stop

# Sudo.
echo "Installing sudo..."
$APT_INSTALL sudo -y
echo "%sudo ALL=NOPASSWD: ALL" | $SUDO tee $WORK/etc/sudoers.d/local > /dev/null
$SUDO chmod 440 $WORK/etc/sudoers.d/local

echo "Choose a root password."
hydra_sudo_run chroot $WORK passwd root

# Fingerprints
hydra_provision_fingerprints

echo "Umounting installation device..."
hydra_sudo_run umount $WORK/sys $WORK/proc $WORK/dev $WORK
hydra_sudo_run cryptsetup luksClose provision-swap
hydra_sudo_run cryptsetup luksClose provision-root
hydra_sudo_run vgchange -a n $vg

cat <<-EOF

Now proceeed with final steps:

  - Create an user account with sudo privileges.
  - Network setup.
  - Review fstab, crypttab and optional GRUB configuration.

See https://padrao.fluxo.info/install for more information.
EOF