#!/bin/bash
# Copyright (C) 2016 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.

set -eE -o pipefail
trap 'echo "$0:$LINENO:error: \"$BASH_COMMAND\" returned $?" >&2' ERR


usage() {
  cat <<EOF
usage: ${0##*/} [-h] [-t 2|test] [-m WIRELESS_MAC]
setup my router in general: dhcp, dns, etc.

Type 2 is for setting up a backup device. Type test is for setting up a
testing device.

Passing an empty string for WIRELESS_MAC will cause the device's native
mac to be used.

EOF

  exit $1
}


dev2=false
test=false
hostname=wrt
libremanage_host=wrt2

lanip=1
while getopts hm:t: opt; do
  case $opt in
    h) usage ;;
    t)
      case $2 in
        2)
          dev2=true
          lanip=4
          hostname=wrt2
          libremanage_host=wrt
          ;;
        test)
          test=true
          ;;
        *) echo "$0: unexpected arg to -t: $*" >&2; usage 1 ;;
      esac
      ;;
    m)  mac=$OPTARG ;;
    *) echo "$0: Internal error! unexpected args: $*" >&2 ; usage 1 ;;
  esac
done
shift "$((OPTIND-1))"   # Discard the options and sentinel --

if [[ ! $mac ]] && ! $test; then
  # if we wanted to increment it
  #WIRELESSMAC=${WIRELESSMAC:0: -1}$((${WIRELESSMAC: -1} + 2))
  mac=$WIRELESSMAC
fi

if (( $# != 0 )); then
  usage 1
fi


macpre=${mac:0: -1}
macsuf=${mac: -1}

pmirror() {
  # background: upgrading all packages is not recommended because it
  # doesn't go into the firmware. build new firmware if you want
  # lots of upgrades. I think /tmp/opkg-lists is a pre openwrt 14 location.
  f=(/var/opkg-lists/*)
  if ! (( $(date -r $f +%s) + 60*60*24 > $(date +%s) )); then
    opkg update
  fi
}

pi() {
  for x in "$@"; do
    if [[ ! $(opkg list-installed "$x") ]]; then
      pmirror
      opkg install "$@"
    fi
  done
}

v() {
  printf "+ %s\n" "$*"
  "$@"
}

######### uci example:#######
# # https://wiki.openwrt.org/doc/uci
# wan_index=$(uci show firewall | sed -rn 's/firewall\.@zone\[([0-9])+\]\.name=wan/\1/p')
# wan="firewall.@zone[$wan_index]"
# if [[ $(uci get firewall.@forwarding[0].dest) != $forward_dest ]]; then
#     # default is wan
#     v uci set firewall.@forwarding[0].dest=$forward_dest
#     uci commit firewall
#     firewall_restart=true
# fi
####### end uci example #####

uset() {
  local key="$1"
  local val="$2"
  local service="${key%%.*}"
  restart_var=${service}_restart
  if [[ ! ${!restart_var} ]]; then
    eval $restart_var=false
  fi
  if [[ $(uci get "$key") != "$val" ]]; then
    v uci set "$key"="$val"
    uci commit $service
    eval $restart_var=true
  fi
}


### network config
###
ssid="check out gnu.org"
lan=10.0.0.0
if $test; then
  ssid="gnuv3"
  lan=10.1.0.0
fi
mask=255.255.0.0
cidr=16
l=${lan%.0}

passwd -l root ||: #already locked fails

sed -ibak '/^root:/d' /etc/shadow
# /root/router created by manually running passwd then copying the resulting
# line. We have no mkpasswd on wrt/librecmc, then we scp it in.
cat /root/router >>/etc/shadow
# otherwise, serial console gets root login with no password
uset system.@system[0].ttylogin 1


cat >/usr/bin/archlike-pxe-mount <<'EOFOUTER'
#!/bin/bash
# symlinks are collapsed for nfs mount points, so use a bind mount.
# tried putting this in /etc/config/fstab,
# then doing block mount, it didn't work. This doesn't persist across reboots,
# todo: figure that out
rm -f /etc/fstab
for d in /run/{arch,parabola}iso/bootmnt; do
cat >>/etc/fstab <<EOF
/mnt/usb/tftpboot $d none bind 0 0
EOF
mount | grep $d &>/dev/null || mount $d
done
/etc/init.d/nfsd restart
EOFOUTER
chmod +x /usr/bin/archlike-pxe-mount

sed -i '/^root:/s,/bin/ash$,/bin/bash,' /etc/passwd
# usb, screen, relay are for libremanage
v pi kmod-usb-storage block-mount kmod-fs-ext4 nfs-kernel-server \
  tcpdump openvpn-openssl adblock libusb-compat /root/relay_1.0-1_mips_24kc.ipk \
  screen kmod-usb-serial-cp210x kmod-usb-serial-ftdi

cat >/etc/libremanage.conf <<EOF
${libremanage_host}_type=switch
${libremanage_host}_channel=1
EOF



v /etc/init.d/fstab enable ||:

# rebooting makes mounting work, but comparing lsmod,
# i'm guessing this will too. todo, test it.
# 255 == module already loaded
for mod in scsi_mod sd_mod; do v modprobe $mod || [[ $? == 255 ]]; done

# for archlike pxe. The default settings in the installer expect to find
# the NFS at one of these dirs
mkdir -p /run/archiso/bootmnt
mkdir -p /run/parabolaiso/bootmnt

# todo: at some later time, i found /mnt/usb not mounted, watch to see if
# that is the case after running this or rebooting.
# wiki says safe to do in case of fstab changes:

## ian: usb broke on old router. if that happens, can just comment this to disable problems
echo | cedit /etc/config/fstab ||:
cedit /etc/config/fstab <<EOF || { v block umount; v block mount; }
config global automount
      option from_fstab 1
      option anon_mount 1

config mount
# /overlay is an / overlay mount for installing extra packages, etc.
# https://openwrt.org/docs/guide-user/additional-software/extroot_configuration
      option target	/mnt/usb
#      option target	/overlay
      option device	/dev/sda1
      option fstype	ext4
      option options	rw,async,noatime,nodiratime
      option enabled	0
EOF


# ian: disabled because afaik I don't need it, no benefit.
# config global autoswap
#       option from_fstab 1
#       option anon_swap 1

# config swap
#       option device	/dev/sda1
#       option enabled	1




# exportfs -ra wont cut it when its the same path, but now a bind mount
# todo: restart nfs when nfs is enabled?
#cedit /etc/exports <<EOF || v /etc/init.d/nfsd restart ||:
cedit /etc/exports <<EOF ||:
/mnt/usb  $lan/$cidr(rw,no_root_squash,insecure,sync,no_subtree_check)
# for arch pxe
/run/archiso/bootmnt	$lan/$cidr(rw,no_root_squash,insecure,sync,no_subtree_check)
/run/parabolaiso/bootmnt	$lan/$cidr(rw,no_root_squash,insecure,sync,no_subtree_check)
EOF


# todo: enable nfs when we need it only.
# v /etc/init.d/portmap start
# v /etc/init.d/nfsd start
# v /etc/init.d/portmap enable
# v /etc/init.d/nfsd enable







uset dropbear.@dropbear[0].PasswordAuth 0
uset dropbear.@dropbear[0].RootPasswordAuth 0
uset dropbear.@dropbear[0].Port 2220
if ! cmp -s /root/dropbear_rsa_host_key /etc/dropbear/dropbear_rsa_host_key; then
  cp /root/dropbear_rsa_host_key /etc/dropbear/dropbear_rsa_host_key
  dropbear_restart=true
fi

wireless_restart=false
key=pictionary49
for x in 0 1; do
  uset wireless.default_radio$x.ssid "$ssid"
  uset wireless.default_radio$x.key $key
  uset wireless.default_radio$x.encryption psk2
  if [[ $mac ]]; then
    uset wireless.default_radio$x.macaddr $macpre$((macsuf + 2*x))
  fi
  # secondary device has wireless disabled
  uset wireless.radio$x.disabled $dev2
done

if $wireless_restart; then
  v wifi
fi


########## openvpn exampl
########## missing firewall settings for routing lan
########## traffic
# v /etc/init.d/openvpn start
# v /etc/init.d/openvpn enable

# # from https://wiki.openwrt.org/doc/uci/firewall
# # todo: not sure if /etc/init.d/network needs restarting.
# # I did, and I had to restart the vpn afterwards.
# # This maps a uci interface to a real interface which is
# # managed outside of uci.
# v cedit /etc/config/network <<'EOF' ||:
# config interface 'tun0'
#         option ifname 'tun0'
#         option proto 'none'
# EOF
# v cedit /etc/config/openvpn <<'EOF' || v /etc/init.d/openvpn restart
# config openvpn my_client_config
#         option enabled 1
#         option config /etc/openvpn/client.conf
# EOF



v cedit /etc/config/network <<EOF || v /etc/init.d/network reload
config 'route' 'transmission'
        option 'interface' 'lan'
        option 'target' '10.173.0.0'
        option 'netmask' '255.255.0.0'
        option 'gateway' '$l.3'
EOF

firewall_restart=false
v cedit /etc/config/firewall <<EOF || firewall_restart=true


config redirect
 option name ssh
 option src              wan
 option src_dport        22
 option dest_ip          $l.8
 option dest             lan
config rule
 option src              wan
 option target           ACCEPT
 option dest_port        22

config redirect
 option name sshalt
 option src              wan
 option src_dport        2222
 option dest_port        22
 option dest_ip          $l.3
 option dest             lan
config rule
 option src              wan
 option target           ACCEPT
 option dest_port        2222

config rule
 option src              wan
 option target           ACCEPT
 option dest_port        2220


config redirect
 option src              wan
 option src_dport        443
 option dest             lan
 option dest_ip          $l.8
 option proto            tcp
config rule
 option src              wan
 option target           ACCEPT
 option dest_port        443
 option proto            tcp

config redirect
 option src              wan
 option src_dport        1196
 option dest             lan
 option dest_ip          $l.8
 option proto            udp
config rule
 option src              wan
 option target           ACCEPT
 option dest_port        1196
 option proto            udp


config redirect
 option src              wan
 option src_dport        80
 option dest             lan
 option dest_ip          $l.8
 option proto            tcp
config rule
 option src              wan
 option target           ACCEPT
 option dest_port        80
 option proto            tcp

config redirect
 option name syncthing
 option src              wan
 option src_dport        22001
 option dest_ip          $l.8
 option dest             lan
config rule
 option src              wan
 option target           ACCEPT
 option dest_port        22001


config rule
 option name ssh-ipv6
 option src wan
 option dest lan
 # note, using mac transform, we could allow all traffic to a host like this,
 # replacing 1 as appropriate
 #option dest_ip ::111:11ff:fe11:1111/::ffff:ffff:ffff:ffff
 option dest_port 22
 option target ACCEPT
 option family ipv6

config rule
 option name http-ipv6
 option src wan
 option dest lan
 option dest_port 80
 option target ACCEPT
 option family ipv6

config rule
 option name http-ipv6
 option src wan
 option dest lan
 option dest_port 80
 option target ACCEPT
 option family ipv6

config rule
 option name node-exporter
 option src wan
 option dest lan
 option dest_port 9101
 option target ACCEPT
 option family ipv6

config rule
 option name mail587-ipv6
 option src wan
 option dest lan
 option dest_port 587
 option target ACCEPT
 option family ipv6


EOF




dnsmasq_restart=false
v cedit /etc/hosts <<EOF || dnsmasq_restart=true
127.0.1.1 wrt
$l.1 wrt
$l.2 kd
$l.3 frodo
$l.4 wrt2
$l.5 x2
$l.6 demohost
$l.7 x3
$l.8 tp b8.nz faiserver
$l.9 bb8
72.14.176.105 li

# netns creation looks for next free subnet starting at 10.173, but I only
# use one, and I would keep this one as the first created.
10.173.0.2 transmission
EOF

#mail_host=$(grep -F mail.iankelling.org /etc/hosts | awk '{print $1}')
# if [[ $mail_host ]]; then
#     sed -i '/^$mail_host/a mail.iankelling.org' /etc/hosts
# fi


# avoid using the dns servers that my isp tells me about.
if [[ $(uci get dhcp.@dnsmasq[0].resolvfile 2>/dev/null) ]]; then
  # default is '/tmp/resolv.conf.auto', we switch to the dnsmasq default of
  # /etc/resolv.conf. not sure why I did this.
  v uci delete dhcp.@dnsmasq[0].resolvfile
  uci commit dhcp
  dnsmasq_restart=true
fi

uset dhcp.@dnsmasq[0].domain b8.nz
uset dhcp.@dnsmasq[0].local /b8.nz/
uset system.@system[0].hostname $hostname

if [[ $(uci get adblock.global.adb_enabled) != 1 ]]; then
  v uci set adblock.global.adb_enabled=1
  uci commit adblock
  /etc/init.d/adblock restart
fi
# https://github.com/openwrt/packages/tree/master/net/adblock/files
cat >/etc/crontabs/root <<'EOF'
0 06 * * *    /etc/init.d/adblock reload
EOF


# useful: http://wiki.openwrt.org/doc/howto/dhcp.dnsmasq

# sometimes /mnt/usb fails, cuz it's just a flash drive,
# so make sure we have this dir or else dnsmasq will fail
# to start.
mkdir -p /mnt/usb/tftpboot
v cedit /etc/dnsmasq.conf <<EOF || dnsmasq_restart=true

# https://ret2got.wordpress.com/2018/01/19/how-your-ethereum-can-be-stolen-using-dns-rebinding/
stop-dns-rebind

# this says the ip of default gateway and dns server,
# but I think they are unneded and default
#dhcp-option=3,$l.1
#dhcp-option=6,$l.1



# results from googling around dnsmasq optimizations
# about 50k in memory. router has 62 megs.
# in a browsing session, I probably won't ever do 5000 lookups
# before the ttl expiration or whatever does expiration.
cache-size=10000

# ask all servers, use the one which responds first.
# http://ma.ttwagner.com/make-dns-fly-with-dnsmasq-all-servers/
all-servers

# namebench benchmarks dns servers. google's dns was only
# slightly less fast than some others, and I trust it more
# to give accurate results, stay relatively fast, and
# not do anythin too malicious, so just use that.
# download namebench and run it like this:
# for x in all regional isp global preferred nearby; do ./namebench.py -s \$x -c US -i firefox -m weighted -J 10 -w; echo \$x; hr;  done
# google
server=8.8.4.4
server=8.8.8.8
server=2001:4860:4860::8888
server=2001:4860:4860::8844


# to fixup existin ips, on the client you can do
# sudo dhclient -r; sudo dhclient <interface-name>

# default dhcp range is 100-150
# bottom port,  iPXE (PCI 03:00.0) in seabios boot menu
dhcp-host=c8:60:00:31:6b:75,set:kd,$l.2,kd
# top port, iPXE (PCI 04:00.0) in seabios boot menu
#dhcp-host=c8:60:00:2b:15:07,set:kd,$l.2,kd
dhcp-host=00:26:18:97:bb:16,set:frodo,$l.3,frodo
# 4 is reserved for a staticly configured host.
dhcp-host=00:1f:16:16:39:24,set:x2,$l.5,x2
# This is so fai can have an explicit name to use for testing,
# or else any random machine which did a pxe boot would get
# reformatted. The mac is from doing a virt-install, cancelling it,
# and copying the generated mac, so it should be randomish.
dhcp-host=52:54:00:9c:ef:ad,set:demohost,$l.6,demohost
dhcp-host=00:1f:16:14:01:d8,set:tp,$l.7,x3
dhcp-host=80:fa:5b:1c:6e:cf,set:tp,$l.8,tp

# faiserver vm
dhcp-host=52:54:00:56:09:f9,set:faiserver,$l.15,faiserver

# This is the ip it picks by default if dhcp fails,
# so might as well use it.
# hostname is the name it uses according to telnet
dhcp-host=b4:75:0e:94:29:ca,set:switch9429ca,$l.251,switch9429ca

# template
# dhcp-host=,$l.,

# Just leave the tftp server up even if we aren't doing pxe boot.
# It has no sensitive info.
enable-tftp=br-lan
tftp-root=/mnt/usb/tftpboot
EOF

uset network.lan.ipaddr $l.$lanip
uset network.lan.netmask $mask
uset dhcp.wan.ignore $dev2 # default is false
uset dhcp.lan.ignore $dev2 # default is false
if $dev2; then
  uset network.lan.gateway $l.1
  uset network.wan.proto none
  uset network.wan6.proto none
else
  # these are the defaults
  uset network.lan.gateway ''
  uset network.wan.proto dhcp
  uset network.wan6.proto dhcpv6
fi


if $dnsmasq_restart; then
  v /etc/init.d/dnsmasq restart
fi

if $firewall_restart; then
  v /etc/init.d/firewall restart
fi



if $network_restart; then
  reboot
fi
if $dropbear_restart; then
  v /etc/init.d/dropbear restart
fi

exit 0