I need a script that, among other things, presents a menu to the user, checks the user input for an IP address (in quad dotted notation), and then "redirects" (with sed) that IP address to the Firewall script.
The script must check that all of the inputs are valid IP addresses (numeric, within 1-255 range, etc).
Well, I have found here on this Forums a magnificent script that does just that. The script is posted bellow.
But the script has a problem... Whenever the user introduces an invalid IP address the script just exits.
I would like another kind of behaviour: When the user introduces an invalid IP address the script should go back, presenting the menu again to the user and re-asking him to introduce a valid IP address.
Could someone please help me? Please someone modify the script bellow in order to accomplish the desired behaviour. I need this to terminate a professional work.
Code:
#!/bin/sh
echo "Enter IP address"
read quad
oldIFS=$IFS
IFS=.
set -- $quad
if [ "$#" -ne "4" ]; then
echo "Must have 4 parts"
exit 1
fi
for oct in $1 $2 $3 $4; do
echo $oct | egrep "^[0-9]+$" >/dev/null 2>&1
if [ "$?" -ne "0" ]; then
echo "$oct: Not numeric"
exit 1
else
if [ "$oct" -lt "0" -o "$oct" -gt "255" ]; then
echo "$oct: Out of range"
exit 1
fi
fi
done
echo "$quad" | grep "\.$" >/dev/null 2>&1
if [ "$?" -eq "0" ]; then
echo "Trailing period - invalid"
exit 1
fi
if [ "$1" -eq "0" ]
then
echo "First octet must not be zero (0)..."
exit 1
fi
# if we're here, we're validated
echo "$quad validates OK!"
exit 0
Last edited by pludi; 12-04-2009 at 03:07 AM..
Reason: code tags, please...
OK I brushed it up a little bit so that is handles ".1.1.1" :
Code:
#!/bin/sh
set -x
oldIFS=$IFS
while : ; do
IFS=$oldIFS
echo "Enter IP address"
read quad
IFS=.
set -- $quad
if [ $# -ne 4 ]; then
echo "Must have 4 parts"
continue
fi
for oct in $1 $2 $3 $4; do
echo $oct | egrep "^[0-9]+$" >/dev/null 2>&1
if [ "$?" -ne "0" ]; then
echo "$oct: Not numeric"
continue 2
else
if [ "$oct" -lt "0" -o "$oct" -gt "255" ]; then
echo "$oct: Out of range"
continue 2
fi
fi
done
echo "$quad" | grep "\.$" >/dev/null 2>&1
if [ "$?" -eq "0" ]; then
echo "Trailing period - invalid"
continue
fi
if [ -n $1 ] || [ $1 -eq 0 ]
then
echo "First octet must not be zero (0)..."
continue
fi
# if we're here, we're validated
echo "$quad validates OK!"
exit 0
done
Not my cup of tea though. Check CFA Johnson's solution:
Last edited by Scrutinizer; 12-04-2009 at 04:02 AM..
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I need a simple script to do the following.
I need to check the user input for
1. quad dotted notation.
2. check that all of the inputs are numeric and within 1-255 range.
Could someone please help me?
I tried to use egrep to check for dotted notation.
quad=1.1.1.12
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12-03-2009
Validate an IP address - Return to menu
