#!/bin/bash
#written in bash for fewest prerequisites
function get_def_interface {
    #gethostbyname on `hostname` would be helpful, but since we
    #are in bash, the best alternative is to use ping to get at it
    #don't want to grep in /etc/hosts or presume DNS
    #we are, however, presuming ipv4 for the moment
    retval=$(ping -c 1 `hostname`|head -n 1|cut -d\( -f 2|cut -d\) -f 1)
    if [ -z "$retval" -o "127.0.0.1" = "$retval" ]; then #ok, that didn't pan out, now we grab the first address that looks sane
        #retval=`ifconfig|grep inet" " |grep -v addr:127.0.0.1|grep -v 'addr:169.254'|head -n 1|cut -d: -f 2|cut -d' ' -f 1`
        retval=`ip -4 -oneline addr show|grep -v "127.0.0.1"|grep -v '169.254'|head -n 1|awk -F 'inet ' '{print $2}'|awk -F '/' '{print $1}'`
    fi
    if [ -z "$retval" ]; then 
        echo "ERROR: Unable to reasonably guess the 'default' interface" >&2
        exit 1
    fi
    #iface=`ifconfig|grep -v inet6|egrep '(Link|inet)'|grep -B1 'addr:'$retval |head -n 1|awk '{print $1}'`
    iface=`ip -4 -oneline addr show|grep -i $retval|awk -F ':' '{print $2}'|awk -F ' ' '{print $1}'|grep -o "[^ ]\+\( \+[^ ]\+\)*"`
    if [ -z "$iface" ]; then
        echo "ERROR: Unable to reasonably guess the default interface" >&2
        exit 1
    fi
    if brctl show | grep ^$iface >& /dev/null; then #
        OIFS=$IFS
        IFS=$'\n'
        INMATCH=0
        for brline in $(brctl show); do
            IFS=$OIFS
            if [ $(expr match "$brline" $iface) == $(expr length $iface) ]; then
                INMATCH=1
                elif [ $(expr match "$brline" " ") != 1 ]; then
                INMATCH=0
            fi
            if [ "$INMATCH" == 1 ];  then
                if ! ethtool -i `echo $brline|awk '{print $NF}'`|grep "driver: tun" >& /dev/null; then
                    iface=`echo $brline|awk '{print $NF}'`
                    echo "$iface"
                    IFS=$OFIS
                    return
                fi
            fi
    done
    IFS=$OFIS
    else 
        echo "$iface"
    fi
}

#before modify the configuration on ubuntu/debian, should preparse the interface file
#By default, All nics configuration are saved into /etc/network/interfaces, it is difficult for xcat to configure nic
#So only use source /etc/network/interfaces.d/* in "/etc/network/interfaces"
#create files under /etc/network/interfaces.d/ for each nic, then it is similar with the readhat and sles
function debianpreconf(){
    #create the config sub dir
    if [ ! -d "/etc/network/interfaces.d" ];then
        mkdir -p "/etc/network/interfaces.d"
    fi
    #search xcat flag
    XCATFLAG=`grep "#XCAT_CONFIG" /etc/network/interfaces`
    if [ -n "$XCATFLAG" ];then
        return
    fi

    #back up the old interface configure
    if [ ! -e "/etc/network/interfaces.bak" ];then
        mv /etc/network/interfaces /etc/network/interfaces.bak
    fi

    #create the new config file
    echo "#XCAT_CONFIG" > /etc/network/interfaces
    echo "source /etc/network/interfaces.d/*" >> /etc/network/interfaces

    CONFFILE=''

    #read the backfile
    cat /etc/network/interfaces.bak | while read LINE
    do
        if [ ! "$LINE" ];then
            continue
        fi
        FIRSTCHAR=${LINE:0:1}
        if [ $FIRSTCHAR = '#' ];then
            continue
        fi

        CONFTYPE=`echo $LINE | cut -d" " -f1`
        if [ $CONFTYPE = 'auto' -o $CONFTYPE = 'allow-hotplug' ];then
            LINE=${LINE#$CONFTYPE}
            for NICNAME in $LINE; do
                echo "$CONFTYPE $NICNAME" > "/etc/network/interfaces.d/$NICNAME"
            done
        elif [ $CONFTYPE = 'iface' -o $CONFTYPE = 'mapping' ];then
            #find out the nic name, should think about the eth0:1
            NICNAME=`echo $LINE | cut -d" " -f 2 | cut -d":" -f 1`
            CONFFILE="/etc/network/interfaces.d/$NICNAME"
            if [ ! -e $CONFFILE ];then
                echo "auto $NICNAME" > $CONFFILE
            fi

            #write lines into the conffile
            echo $LINE >> $CONFFILE
        else
            echo $LINE >> $CONFFILE
        fi

    done
}

if [ "storageprereq" = "$1"  ]; then
    MOUNTURI="$2"
    DIRNAME=`echo $MOUNTURI|sed -e 's!nfs://!nfs_!'`
    MOUNTPATH=`echo $DIRNAME|sed -e 's!nfs_!!'|sed -e 's!/!:/!'`
    if mount|grep $MOUNTPATH > /dev/null; then
        exit 0;
    fi
    mkdir -p /var/lib/xcat/vmnt/$DIRNAME
    mount $MOUNTPATH /var/lib/xcat/vmnt/$DIRNAME
elif [ "bridgeprereq" = "$1" ]; then
    # load the bridge module first
    modprobe bridge

    NETDESC="$2"
    # get the port for installation
    if [ -n "$INSTALLNIC" ]; then
        if [[ "$INSTALLNIC" = mac ]] || [[ "$INSTALLNIC" = MAC ]]; then
            #INSPORT=`ifconfig -a|grep -v inet6| grep -i 'HWaddr '$MACADDRESS|head -n 1|awk '{print $1}'`
            INSPORT=`ip -oneline link show|grep -i ether|grep -i $MACADDRESS|awk -F ':' '{print $2}'|grep -o "[^ ]\+\( \+[^ ]\+\)*"`
        else
            INSPORT=$INSTALLNIC
        fi
    fi

    if [ -z "$NETDESC" ]; then
        if [ -n "$INSTALLNIC" ]; then
          NETDESC=$INSPORT:default
        else
            echo "Incorrect usage"
            exit 1
        fi
    fi
    if echo "$NETDESC"|grep ':'> /dev/null; then
        PORTS=`echo "$NETDESC"|cut -d: -f 1`
        BNAME=`echo "$NETDESC"|cut -d: -f 2`
    else 
        if [ -n "$INSTALLNIC" ]; then
            PORTS=$INSPORT
        fi
        BNAME=$NETDESC
    fi
    if brctl showstp "$BNAME" > /dev/null; then
        echo "$BNAME"
        exit 0
    fi
    #Still here, that means we must build a bridge
    if [ -z "$PORTS" ]; then #No ports specified, default to whatever looks up
        PORTS=$(get_def_interface)
    fi
    if [ -z "$PORTS" ]; then #This has been checked many times before in theory, check again just in case
        exit 1
    fi
    #For now, we only support bridge name==network name.  This precludes
    #the config of the same vlan number on multiple fabrics, but
    #will cover that flexibility later if demanded (with 4k vlan ids, 
    #I think it would be unwise to reuse them as it could confuse anyway)
    if echo "$PORTS"|grep '&'; then #we have bonding... fun to be had
    #To be slack, going to just support one bond for now..
        modprobe bonding miimon=100 mode=4
        PORTS=`echo $PORTS |sed -e 's/&/ /'`
        ip link set bond0 up
        for p in $PORTS; do
            #TODO: we are only going to manage the default
            #route for now
            saveroutes=`ip route | grep default| grep "dev $p"|grep via|sed -e 's/dev .*//'`
            OIFS=$IFS
            IFS=$'\n'
            saveip=`ip addr show dev $p scope global|grep inet|grep -v dynamic|sed -e 's/inet.//'|sed -e 's/[^ ]*$//'`
            if [ ! -z "$saveip" ]; then
                for line in $saveip; do 
                    ip addr add dev bond0 $line
                done
            fi
            IFS=$OIFS
            ifenslave bond0 $p
            if [ ! -z "$saveroutes" ]; then
                ip route add $saveroutes
            fi 
        done
        PORTS=bond0
    fi
    if echo "$BNAME"|egrep '^vl(an)?[0123456789]' > /dev/null; then 
        vlan="yes"
        TNAME=${BNAME##vl}
        TNAME=${TNAME##an}
        #We have a vlan... more fun
        modprobe 8021q
        vconfig add $PORTS $TNAME
        vconfig set_flag $PORTS.$TNAME 2 1 #Turn on GVRP where supported
        ip link set $PORTS.$TNAME up
        PORTORG=$PORTS
        PORTS=$PORTS.$TNAME
    fi
    #Now, $PORTS is 'the' physical device to participate in a bridge
    #TODO: we are only going to manage the default
    #route for now
    brctl addbr $BNAME
    brctl setfd $BNAME 0 #fast forwarding
    ip link set $BNAME up
    saveroutes=`ip route | grep default| grep "dev $PORTS"|grep via|sed -e 's/dev .*//'`
    OIFS=$IFS
    IFS=$'\n'
    saveip=`ip addr show dev $PORTS scope global|grep inet|grep -v dynamic|sed -e 's/inet.//'|sed -e 's/[^ ]*$//'`
    #saveip=`ip addr show dev $PORTS scope global|grep inet|sed -e 's/inet.//'|sed -e 's/[^ ]*$//'`
    if [ ! -z "$saveip" ]; then
        for line in $saveip; do 
            IFS=$OIFS
            ip addr add dev $BNAME $line
        done
    else
        if [ ! -z "$3" ]; then
            ip addr add dev $BNAME $3 
        fi
    fi
    brctl addif $BNAME $PORTS
    if [ ! -z "$saveip" ]; then
        OIFS=$IFS
        IFS=$'\n'
        for line in $saveip; do 
            IFS=$OIFS
            ip addr del dev $PORTS $line
        done
       IFS=$OIFS
    fi
    IFS=$OIFS
    if [ ! -z "$saveroutes" ]; then
        ip route add $saveroutes
    fi
    
    #now save the settings into the config files so that they will be persistent among reboots
    if [[ $OSVER = sles* ]] || [[ $OSVER = suse* ]] || [[ -f /etc/SuSE-release ]]; then
        nwdir="/etc/sysconfig/network"
        isSLES=1
    elif [ -f "/etc/debian_version" ];then
        debianpreconf
        nwdir="/etc/network/interfaces.d"
        isDebian=1
        getcap /usr/bin/qemu-system-x86_64 | grep cap_net_admin
        if [ $? ne 0 ];then
            setcap cap_net_admin=ei /usr/bin/qemu-system-x86_64
        fi
    else 
        nwdir="/etc/sysconfig/network-scripts"
    fi 
    
     #write into the network configuration file
    if [[ $isSLES -eq 1 ]]; then
        cat >$nwdir/ifcfg-$PORTS <<EOF
DEVICE='$PORTS'
ONBOOT='yes'
BRIDGE='$BNAME'
EOF
        mac=`ip addr show dev $PORTS scope global|grep link|sed -e 's/link\/ether//'|sed -e 's/brd.*$//'|sed -e 's/[ ]*//'`
        if [ ! -z "$mac" ]; then
            echo "HWADDR='$mac'" >> $nwdir/ifcfg-$PORTS
        fi
        if [ ! -z "$vlan" ]; then
            echo "VLAN='yes'" >> $nwdir/ifcfg-$PORTS
        fi
        cat >$nwdir/ifcfg-$BNAME <<EOF      
DEVICE='$BNAME'
TYPE='Bridge'
ONBOOT='yes'
PEERDNS='yes'
DELAY='0'
EOF
        if [ ! -z "$3" ]; then 
            echo "IPADDR='$3'" >> $nwdir/ifcfg-$BNAME 
            if [ ! -z "$4" ]; then
                echo "NETMASK='$4'" >> $nwdir/ifcfg-$BNAME
            fi
        else
            echo "BOOTPROTO=dhcp" >> $nwdir/ifcfg-$BNAME
        fi
    elif [ $isDebian ];then
        #ubuntu/debian
        echo "auto $PORTS" >$nwdir/$PORTS
        echo "iface $PORTS inet manual" >> $nwdir/$PORTS
        
        if [ ! -z "$vlan" ];then
            echo "  vlan-raw-device $PORTORG"
        fi

        echo "auto $BNAME" > $nwdir/$BNAME
        if [ ! -z "$3" ];then
            echo "iface $BNAME inet static" >> $nwdir/$BNAME
            echo "  address $3" >> $nwdir/$BNAME
            if [ ! -z "$4" ];then
                echo "  netmask $4" >> $nwdir/$BNAME
            else
                echo "  netmask 255.255.255.0" >> $nwdir/$BNAME
            fi
        else
            echo "iface $BNAME inet dhcp" >> $nwdir/$BNAME
        fi
        echo "  bridge_ports $PORTS" >> $nwdir/$BNAME
        echo "  bridge_stp off" >> $nwdir/$BNAME
        echo "  bridge_fd 0" >> $nwdir/$BNAME
        echo "  bridge_maxwait 0" >> $nwdir/$BNAME
    else
        cat >$nwdir/ifcfg-$PORTS <<EOF
DEVICE=$PORTS
ONBOOT=yes
BRIDGE=$BNAME
EOF
        mac=`ip addr show dev $PORTS scope global|grep link|sed -e 's/link\/ether//'|sed -e 's/brd.*$//'|sed -e 's/[ ]*//'`
        if [ ! -z "$mac" ]; then
            echo "HWADDR=$mac" >> $nwdir/ifcfg-$PORTS
        fi
        if [ ! -z "$vlan" ]; then
            echo "VLAN=yes" >> $nwdir/ifcfg-$PORTS
        fi
        cat >$nwdir/ifcfg-$BNAME <<EOF      
DEVICE=$BNAME
TYPE=Bridge
ONBOOT=yes
PEERDNS=yes
DELAY=0
EOF
        if [ ! -z "$3" ]; then 
            echo "IPADDR=$3" >> $nwdir/ifcfg-$BNAME 
            if [ ! -z "$4" ]; then
                echo "NETMASK=$4" >> $nwdir/ifcfg-$BNAME
            fi
        else
            echo "BOOTPROTO=dhcp" >> $nwdir/ifcfg-$BNAME
        fi
    fi 
 
    ifup $BNAME
fi #END bridge config.