Chip 2007 January, February, March & April/Chip-Cover-CD-2007-02.iso/boot/i386/root/usr/lib/YaST2/servers_non_y2/ag_hostnames

Text File | 2006-11-29 | 4.6 KB | 200 lines

#!/bin/bash

# File:        ag_hostnames
# Package:    Network configuration
# Summary:    Agent for reading hostnames from local network
# Authors:    Michal Svec, Martin Vidner
#
# $Id: ag_hostnames 17789 2004-06-11 12:13:04Z visnov $
#
# Agent for reading
# - hostnames from local network
# - hostnames of hosts that have a particular TCP port open
# - hostnames of hosts that have a particular RPC service open
# - hostnames of samba servers
#
# Note: hostnames are not sorted.

if [ x$1 = x-d ]; then
    set -x
else
    exec 2>/dev/null
fi

# We want to parse English output
export LC_ALL=C

# this function is duplicated in ag_showexports and ag_hostnames
# after $1 seconds, kill $2 and all its children
# return $2's exit status
function kill_after() {
    local TIMEOUT=$1
    local LONG_PID=$2

    {
    sleep $TIMEOUT
    LONG_CHILDREN_PIDS=`ps --ppid $LONG_PID --no-headers -o pid`
    kill $LONG_PID $LONG_CHILDREN_PIDS
    } &
    SLEEP_PID=$!

    # now wait until the long command finishes or is killed
    wait $LONG_PID
    local RET=$?
    # if it did not exit because of a signal,
    # then the killer is useless and we will kill him instead
    if [ $RET -lt 128 ]; then
    kill $SLEEP_PID
    fi
    return $RET
}

# RETVAL convention avoids passing return values as stdout
# and thus spawning new processes

# uses RETVAL
function ycp_item() {
    RETVAL="\"$1\", "
}

function lookup_ip() {
    local ip=$1
    if [ $BADLOOKUP != 4 ] ; then
#    NAME=$(dig +short +tries=1 +time=1 -x $ip | sed -e 's/\.$//')
#    NAME=$(dig +short -x $ip | sed -e 's/\.$//')
#    NAME=$(host -W1 $ip | sed -n '/.*domain name pointer \(.*\)\.$/s//\1/p')
    NAME="$(getent hosts "$ip" | sed -e 's/^[0-9. ]*//')"
    [ -z "$NAME" ] && BADLOOKUP=$(expr $BADLOOKUP + 1)
    NAME="${NAME:-$ip}"
    else
    NAME="$ip"
    fi
    RETVAL="$NAME"
}

# uses RETVAL
function broadcast_addr() {
    # may be empty
    local INTERFACE=$1
    RETVAL=$(/sbin/ifconfig $INTERFACE | sed -n '/.*Bcast:\([0-9.]*\).*/s//\1/p' | head -n 1)
}

# uses RETVAL
function broadcast_ping() {
    # wait long enough to gather as many hosts as possible, #40582
    RETVAL=$(ping -b -w 10 "$BROADCAST" | sed -n '/.*from \([0-9.]\+\).*/s//\1/p'  | sort -u)
}

# uses exit status
# is_port_open $ADDR $PORT
function is_port_open() {
    /usr/bin/netcat -w 1 -z $1 $2
}

# uses exit status
# is_rpc_service_open_long $ADDR $SERVICE
function is_rpc_service_open_long() {
    #hack: not quoting $2 enables scanning for a particular version
    /usr/sbin/rpcinfo -u "$1" $2 >/dev/null || \
    /usr/sbin/rpcinfo -t "$1" $2 >/dev/null
}

# uses exit status
# is_rpc_service_open $ADDR $SERVICE
# calls is_rpc_service_open but kills it if it takes too long
function is_rpc_service_open() {
    is_rpc_service_open_long "$1" "$2" &
    kill_after 2 $!
#    local RET=$?
#    echo "result: $RET" >&2
#    return $RET
}

# hostnames [-p portnum|-r rpcservice] [interface]
# echoes the output
function hostnames() {
    local PORT
    local SERVICE
    local INTERFACE
    if [ x$1 = x-p ]; then
    PORT=$2
    shift 2
    elif [ x$1 = x-r ]; then
    SERVICE="$2"
    shift 2
    fi
    INTERFACE=$1

    BADLOOKUP=0
    if [ $IP_ONLY != 0 ]; then
    BADLOOKUP=4
    fi
    broadcast_addr $INTERFACE; BROADCAST=$RETVAL
    if [ "$BROADCAST" ] ; then
    broadcast_ping; IPS=$RETVAL
    ANSWER=
    for IP in $IPS ; do
        # filter out hosts that do not have the wanted service
        if [ -n "$PORT" ]; then
        is_port_open $IP $PORT || IP=""
        elif [ -n "$SERVICE" ]; then
        is_rpc_service_open $IP "$SERVICE" || IP=""
        fi

        if [ -n "$IP" ] ; then
        lookup_ip $IP; ycp_item $RETVAL; ANSWER="$ANSWER $RETVAL"
        fi
    done
    echo '[' "$ANSWER" ']'
    else
    echo '[]'
    fi
}

while true ; do
    IFS=
    read COMMAND || exit
    unset IFS
    # strip leading backquote introduced by NI
    COMMAND=${COMMAND#\`}

    IP_ONLY=0
    case "$COMMAND" in
    "result ("*)
        exit
        ;;
    'Dir (.)')
        echo '[ "rpc", "interface", "samba" ]'
        ;;
    'Read (.)')
        hostnames
        ;;
    'Read (.,'*)
        PORT=$(echo "$COMMAND" | sed 's/^Read (., *\(.*\))/\1/')
        hostnames -p $PORT
        ;;
    'Read (.rpc,'*)
        SERVICE=$(echo "$COMMAND" | sed 's/^Read (.rpc, *"\(.*\)")/\1/')
        hostnames -r "$SERVICE"
        ;;
    'Read (.ip.rpc,'*)
        SERVICE=$(echo "$COMMAND" | sed 's/^Read (.ip.rpc, *"\(.*\)")/\1/')
        IP_ONLY=1
        hostnames -r "$SERVICE"
        ;;
    'Read (.interface,'*)
        INTERFACE=$(echo "$COMMAND" | sed 's/^Read (.interface, *"\(.*\)")/\1/')
        hostnames $INTERFACE
        ;;
    'Read (.samba)')
        echo -n [
        nmblookup -M -T - | awk -F '[, \t]+' '/<01>/ { printf "\"%s\", ", $1; }'
        echo ]
        ;;
    *)
        echo nil
    esac
done

# EOF