#!/usr/bin/env bash

# Prowler - the handy cloud security tool (copyright 2019) by Toni de la Fuente
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may not
# use this file except in compliance with the License. You may obtain a copy
# of the License at http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software distributed
# under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
# CONDITIONS OF ANY KIND, either express or implied. See the License for the
# specific language governing permissions and limitations under the License.

CHECK_ID_check43="4.3"
CHECK_TITLE_check43="[check43] Ensure the default security group of every VPC restricts all traffic (Scored)"
CHECK_SCORED_check43="SCORED"
CHECK_TYPE_check43="LEVEL2"
CHECK_SEVERITY_check43="High"
CHECK_ASFF_TYPE_check43="Software and Configuration Checks/Industry and Regulatory Standards/CIS AWS Foundations Benchmark"
CHECK_ASFF_RESOURCE_TYPE_check43="AwsEc2SecurityGroup"
CHECK_ALTERNATE_check403="check43"
CHECK_ASFF_COMPLIANCE_TYPE_check43="ens-mp.com.4.aws.sg.1"
CHECK_SERVICENAME_check43="ec2"
CHECK_RISK_check43='Even having a perimeter firewall; having security groups open allows any user or malware with vpc access to scan for well known and sensitive ports and gain access to instance.'
CHECK_REMEDIATION_check43='Apply Zero Trust approach. Implement a process to scan and remediate unrestricted or overly permissive security groups. Recommended best practices is to narrow the definition for the minimum ports required.'
CHECK_DOC_check43='https://docs.aws.amazon.com/eks/latest/userguide/sec-group-reqs.html'
CHECK_CAF_EPIC_check43='Infrastructure Security'

check43(){
  # "Ensure the default security group of every VPC restricts all traffic (Scored)"
  for regx in $REGIONS; do
    CHECK_SGDEFAULT_IDS=$($AWSCLI ec2 describe-security-groups $PROFILE_OPT --region $regx --filters Name=group-name,Values='default' --query 'SecurityGroups[*].GroupId[]' --output text)
    for CHECK_SGDEFAULT_ID in $CHECK_SGDEFAULT_IDS; do
      CHECK_SGDEFAULT_ID_OPEN=$($AWSCLI ec2 describe-security-groups $PROFILE_OPT --region $regx --group-ids $CHECK_SGDEFAULT_ID --query 'SecurityGroups[*].{IpPermissions:IpPermissions,IpPermissionsEgress:IpPermissionsEgress,GroupId:GroupId}' --output text |egrep '\s0.0.0.0|\:\:\/0')
      if [[ $CHECK_SGDEFAULT_ID_OPEN ]];then
        textFail "Default Security Groups ($CHECK_SGDEFAULT_ID) found that allow 0.0.0.0 IN or OUT traffic in Region $regx" "$regx" "$CHECK_SGDEFAULT_ID"
      else
        textPass "No Default Security Groups ($CHECK_SGDEFAULT_ID) open to 0.0.0.0 found in Region $regx" "$regx" "$CHECK_SGDEFAULT_ID"
      fi
    done
  done
}