#!/bin/bash
# postinst script for #PACKAGE#
#
# see: dh_installdeb(1)

set -e

# summary of how this script can be called:
#        * <postinst> `configure' <most-recently-configured-version>
#        * <old-postinst> `abort-upgrade' <new version>
#        * <conflictor's-postinst> `abort-remove' `in-favour' <package>
#          <new-version>
#        * <postinst> `abort-remove'
#        * <deconfigured's-postinst> `abort-deconfigure' `in-favour'
#          <failed-install-package> <version> `removing'
#          <conflicting-package> <version>
# for details, see https://www.debian.org/doc/debian-policy/ or
# the debian-policy package


case "$1" in
    configure)


     ### START gather all the info from the box and generate the variabels

        export LOOPBACKv4=$(dig a +short ${HOSTNAME})
        export LOOPBACKv6=$(dig aaaa +short ${HOSTNAME})
        NODEASN=$(dig txt +short asn.${HOSTNAME})
        NODEASN="${NODEASN%\"}"
        NODEASN="${NODEASN#\"}"
        export NODEASN

        if [ -z $LOOPBACKv4 ] || [ -z $LOOPBACKv6 ] || [ -z $NODEASN ]; then
            echo "unable to find my LOOPBACK IP and/or ASN: $LOOPBACKv4/$LOOPBACKv6/$NODEASN"
            exit 2
        fi

        declare -A MACS
        for if in mgmt feth1 feth2 feth3 fet4 up1 up2 up3 up4 ibgp1 ibgp2 ibgp3 ibgp4
          do
            MACS["$if"]=$(dig txt +short mac.$if.$HOSTNAME)    ## careful mac will be wrapped in quotes, but we don't care since we'll need it again wrapped in quotes (so far)
        done

     ## END variables


     ## START writing config files


      # disable password logins on ssh
        sed -i -e '/#*\s*PasswordAuthentication /d' /etc/ssh/sshd_config
        echo "PasswordAuthentication no" >>/etc/ssh/sshd_config



      # set network interface configurations
        cat <<-EOF >/etc/network/interfaces
		source-directory /etc/network/interfaces.d
	EOF

        cat <<-EOF >/etc/network/interfaces.d/lo
		auto lo
		iface lo inet loopback

		iface lo inet static
		    address ${LOOPBACKv4}/32

		iface lo inet6 static
		    address ${LOOPBACKv6}/128
	EOF

	cat <<-"EOF" >/etc/network/interfaces.d/mgmt1
		auto mgmt1
		iface mgmt1 inet dhcp
		    pre-up /bin/ip link add mgmt type vrf table mgmt
		    pre-up /bin/ip link set up dev mgmt
		    pre-up /bin/ip link set master mgmt dev mgmt1
		    post-down /bin/ip link del dev mgmt
		iface mgmt1 inet6 auto
	EOF

	cat <<-"EOF" >/etc/network/interfaces.d/feth
	auto feth1
	iface feth1 inet manual
	    mtu 9000

	auto feth2
	iface feth2 inet manual
	    mtu 9000
	EOF




      # set frr config
        sed -i -e "s/FRRROUTERID/${LOOPBACKv4}/" -e "s/NODEASN/${NODEASN}/" /etc/frr/frr.conf.wit 
        chown frr.frr /etc/frr/frr.conf.wit /etc/frr/daemons.wit




      # set ipsec config
        sed -i -e "s/FQHOSTNAME/${HOSTNAME}/" /etc/ipsec.conf.wit
        echo ": RSA ${HOSTNAME}.key" >/etc/ipsec.secrets




      # write udev rules for device names
        for if in ${!MACS[@]}
          do
            ifmac=${MACS[$if]}
            [ "$if" == "mgmt" ] && if=mgmt1
            [ -z "$ifmac" ] || echo 'SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=='$ifmac', ATTR{type}=="1", NAME="'${if}'"'
        done >/etc/udev/rules.d/70-persistent-net.rules




      # wite grub rules for serial terminal
        sed -i -e '/GRUB_CMDLINE_LINUX_DEFAULT=/d' -e '/GRUB_CMDLINE_LINUX=/d' -e '/GRUB_SERIAL_COMMAND=/d' -e '/GRUB_TERMINAL=/d' /etc/default/grub
	cat <<-EOF >>/etc/default/grub
		GRUB_CMDLINE_LINUX_DEFAULT=""
		GRUB_CMDLINE_LINUX="console=tty0 console=ttyS1,115200n8"
		GRUB_TERMINAL=serial
		GRUB_SERIAL_COMMAND="serial --speed=115200 --unit=1 --word=8 --parity=no --stop=1"
	EOF


    ## END config file section


    ## START configuring services as we need it

        systemctl enable firewall
        systemctl restart systemd-timesyncd
        systemctl restart ssh
        
        update-grub
        
        sysctl -p /etc/sysctl.d/10-frr.conf

    ## END services section


    ;;

    abort-upgrade|abort-remove|abort-deconfigure)
    ;;

    *)
        echo "postinst called with unknown argument \`$1'" >&2
        exit 1
    ;;
esac

# dh_installdeb will replace this with shell code automatically
# generated by other debhelper scripts.

#DEBHELPER#

exit 0