Network script & bash ip validator

[Auke Kok]

hmmm

I think I'm gonna replace the regex with code that just passes the 
contents of that var directly to ifconfig... this type of validity 
checking is really out of place indeed (I also have the funny feeling 
that in bash-3.00 the left-associative binding of ')' in a case 
statement changed somehow...)

Anyway this would reduce the problem to: "User must provide valid 
input". Any errors displayed consequently will result in the iface not 
being brought up and a proper message by ifconfig itself, rather 
appropriate I'd say.

objections?

Auke


Stefan Wold wrote:

> Good idea, but wrong place to add it. A check is already done to see 
> if ifconfig successfully set an ipaddress, otherwise it will tell you 
> it failed. Ifconfig would not accept invalid ipaddress's, which is 
> something your little hack does.
> [0-9]{1,3}  would allow addresses like 999.999.999.999.
>
> If something like this really is needed a better place to add it would 
> be in the "lnet" tool, not in the start up scripts.
>
> Sincerely
> Stefan Wold
>
>
>
> n Thu, 3 Feb 2005, Couannette wrote:
>
>> Hi
>>
>> I modified /etc/init.d/network, adding an IP validator function.
>> What do you think of that ?
>>
>> Best regards,
>>
>> Couannette
>>
>> --- network    2003-12-18 11:07:08.000000000 +0100
>> +++ network.m    2005-02-03 12:16:19.757771241 +0100
>> @@ -6,10 +6,27 @@
>> # description: Activates/Deactivates all network interfaces 
>> configured to \
>> #              start at boot time.
>> # probe: true
>> -
>> +set -x
>> shopt -s extglob
>> CONFIGS=/etc/config.d/network
>>
>> +to_lower () { tr 'A-Z' 'a-z' <<< "$*"; }
>> +ip_validator () {
>> +    _IFS=$IFS
>> +    IFS=. numbers=( $1 )
>> +    IFS=$_IFS
>> +    if [ ${#numbers[@]} == 4 ] ; then
>> +    for i in ${numbers[*]} ; do
>> +        if [[ ! "$i" =~ "[0-9]{1,3}" ]] ; then
>> +        return 1
>> +        fi
>> +    done
>> +    else
>> +    return 1
>> +    fi
>> +    return 0
>> +}
>> +
>> chkresult() {
>>   if [ $? -eq "-1" ] ; then
>>       echo -e $RESULT_FAIL
>> @@ -67,23 +84,25 @@
>>         return -1;
>>     fi;
>>
>> -    case $ADDRESS in
>> -        [dD][hH][cC][pP])
>> +    address=$(to_lower $ADDRESS)
>> +    case $address in
>> +        dhcp)
>>             if [ -z $DHCP_CLIENT ]; then
>>             echo -n "DHCP client not specified";
>>             return -1;
>>         fi;
>> -        case $DHCP_CLIENT in
>> -            [dD][hH][cC][pP][cC][dD])
>> +        dhcp_client=$(to_lower $DHCP_CLIENT)
>> +        case $dhcp_client in
>> +            dhcpcd)
>>                 PIDFILE=/etc/dhcpc/dhcpcd-$1.pid
>>             RUNFILE=/usr/sbin/dhcpcd
>>             ;;
>> -            [dD][hH][cC][lL][iI][eE][nN][tT])
>> +            dhclient)
>>                 PIDFILE=/var/run/dhclient-$1.pid
>>             RUNFILE=/sbin/dhclient
>>             DHCP_OPTIONS="$DHCP_OPTIONS -pf $PIDFILE -lf 
>> /var/state/dhcp/dhclient-$1.leases"
>>             ;;
>> -            [uU][dD][hH][cC][pP][cC])
>> +            udhcpc)
>>                 PIDFILE=/var/run/udhcpc-$1.pid
>>             RUNFILE=/sbin/udhcpc
>>             DHCP_OPTIONS="$DHCP_OPTIONS -p $PIDFILE -i"
>> @@ -114,7 +133,11 @@
>>             fi;
>>         fi;
>>         ;;
>> - 
>> ?([0-9])?([0-9])[0-9].?([0-9])?([0-9])[0-9].?([0-9])?([0-9])[0-9].?([0-9])?([0-9])[0-9]) 
>>
>> +        *)  # we must validate IP addr
>> +        if ! ip_validator $address ; then
>> +            echo -n "IP address $address is not valid"
>> +            return -1
>> +        fi
>>         if [ ! -x /sbin/ifconfig ]; then
>>             echo -n "ifconfig not installed";
>>             return -1;
>> @@ -152,14 +175,16 @@
>>
>>     . $CONFIGS/$1;
>>
>> -    case $ADDRESS in
>> -        [dD][hH][cC][pP])
>> -            case $DHCP_CLIENT in
>> -            [dD][hH][cC][pP][cC][dD])
>> +    address=$(to_lower $ADDRESS)
>> +    case $address in
>> +        dhcp)
>> +        dhcp_client=$(to_lower $DHCP_CLIENT)
>> +            case $dhcp_client in
>> +            dhcpcd)
>>             KILLCMD="dhcpcd -k"
>>                 PIDFILE=/etc/dhcpc/dhcpcd-$1.pid
>>             ;;
>> -            [dD][hH][cC][lL][iI][eE][nN][tT])
>> +            dhclient)
>>                 PIDFILE=/var/run/dhclient-$1.pid
>>             ;;
>>         esac
>> @@ -187,7 +212,11 @@
>>             esac
>>             fi;
>>         ;;
>> - 
>> ?([0-9])?([0-9])[0-9].?([0-9])?([0-9])[0-9].?([0-9])?([0-9])[0-9].?([0-9])?([0-9])[0-9]) 
>>
>> +        *)  # we must validate IP addr
>> +        if ! ip_validator $address ; then
>> +            echo -n "IP address $address is not valid"
>> +            return -1
>> +        fi
>>         if [ `ifconfig | grep $1 | wc -l` -eq 1 ]; then
>>             if [ ! -x /sbin/ifconfig ]; then
>>                    echo -n "ifconfig not installed";
>
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