Repoint AWS EC2 Security Group inbound access to my current IP address

aws_repoint_to_my_ip.sh

#!/bin/bash

# Summary:
# Bash script repoints all inbound access for a given AWS EC2 security group
# to your current IP addr(v4) as provided by ifconfig.me/ip 

# To use this script: 
# Pass the name of a security group as a command line argument
# e.g. $ aws_repoint_to_my_ip.sh SECURITYGROUPNAME

# Notes:
# You need to have AWS CLI installed and configured. See http://aws.amazon.com/cli/
# To setup, see this page http://docs.aws.amazon.com/cli/latest/userguide/cli-chap-getting-set-up.html
# See also: http://www.joyofdata.de/blog/guide-to-aws-ec2-on-cli/

if [ $# -eq 0 ] 
  then
    echo -e 'Please provide the name of a security group\n\te.g.  . aws_repoint_to_my_ip.sh SECURITYGROUPNAME'
    return 1
fi

# Search for the group-id based on the Group Name provided
MYGROUPNAME=$1 # $1 is SECURITYGROUPNAME argument passed to the script

# Get my IP addr(v4) alternatives: curl icanhazip.com; curl ifconfig.me/ip
MYIP=$(curl checkip.amazonaws.com)

# Print all existing inbound access 
echo ''
echo 'Current entries for group: '$MYGROUPNAME 
aws ec2 describe-security-groups \
        --filters Name=group-name,Values=$MYGROUPNAME \
        --query 'SecurityGroups[0].IpPermissions[*].{ip:IpRanges[0].CidrIp,protocol:IpProtocol,from:FromPort,to:ToPort}' \
        --output table

# Revoke all existing inbound access
echo ''
aws ec2 describe-security-groups \
        --filters Name=group-name,Values=$MYGROUPNAME \
        --query 'SecurityGroups[0].IpPermissions[*].[IpRanges[0].CidrIp,IpProtocol,FromPort,ToPort]' \
        --output text \
    | awk -v grpnm=${MYGROUPNAME} -v newip=${MYIP} '{ 
    print   "aws ec2 revoke-security-group-ingress    --group-name "grpnm" --cidr "$1" --protocol "$2" --port "$3;
    system ("aws ec2 revoke-security-group-ingress --group-name "grpnm" --cidr "$1" --protocol "$2" --port "$3" > /dev/null 2>&1");
    print   "aws ec2 authorize-security-group-ingress --group-name "grpnm" --cidr "newip"/32 --protocol "$2" --port "$3;
    system ("aws ec2 authorize-security-group-ingress --group-name "grpnm" --cidr "newip"/32 --protocol "$2" --port "$3" > /dev/null 2>&1");
    }'  # " > /dev/null 2>&1" : This pipes stdin and stderr responses to dev/null. Remove if you would like to see the
        # response from the server printed on screen    

# Print all new inbound access
echo ''
echo ''
echo 'New entries for group: '$MYGROUPNAME 
aws ec2 describe-security-groups \
        --filters Name=group-name,Values=$MYGROUPNAME \
        --query 'SecurityGroups[0].IpPermissions[*].{ip:IpRanges[0].CidrIp,protocol:IpProtocol,from:FromPort,to:ToPort}' \
        --output table