#!/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_check29="2.9"
CHECK_TITLE_check29="[check29] Ensure VPC Flow Logging is Enabled in all VPCs"
CHECK_SCORED_check29="SCORED"
CHECK_TYPE_check29="LEVEL2"
CHECK_SEVERITY_check29="Medium"
CHECK_ASFF_TYPE_check29="Software and Configuration Checks/Industry and Regulatory Standards/CIS AWS Foundations Benchmark"
CHECK_ASFF_RESOURCE_TYPE_check29="AwsEc2Vpc"
CHECK_ALTERNATE_check209="check29"
CHECK_ASFF_COMPLIANCE_TYPE_check29="ens-op.mon.1.aws.flow.1"
CHECK_SERVICENAME_check29="vpc"
CHECK_RISK_check29='PC Flow Logs provide visibility into network traffic that traverses the VPC and can be used to detect anomalous traffic or insight during security workflows.'
CHECK_REMEDIATION_check29='It is recommended that VPC Flow Logs be enabled for packet "Rejects" for VPCs. '
CHECK_DOC_check29='http://docs.aws.amazon.com/AmazonVPC/latest/UserGuide/flow-logs.html '
CHECK_CAF_EPIC_check29='Logging and Monitoring'

check29(){
  # "Ensure VPC Flow Logging is Enabled in all VPCs (Scored)"
  for regx in $REGIONS; do
    AVAILABLE_VPC=$($AWSCLI ec2 describe-vpcs $PROFILE_OPT --region $regx --query 'Vpcs[?State==`available`].VpcId' --output text 2>&1)
    if [[ $(echo "$AVAILABLE_VPC" | grep AccessDenied) ]]; then
      textFail "$regx: Access Denied trying to describe VPCs" "$regx" "$vpcx"
      continue
    fi
    for vpcx in $AVAILABLE_VPC; do
      CHECK_FL=$($AWSCLI ec2 describe-flow-logs $PROFILE_OPT --region $regx --filter Name="resource-id",Values="${vpcx}" --query 'FlowLogs[?FlowLogStatus==`ACTIVE`].FlowLogId' --output text 2>&1)
      if [[ $(echo "$CHECK_FL" | grep AccessDenied) ]]; then
        textFail "$regx: VPC $vpcx Access Denied trying to describe flow logs" "$regx" "$vpcx"
        continue
      fi
      if [[ $CHECK_FL ]]; then
        for FL in $CHECK_FL; do
          textPass "$regx: VPC $vpcx VPCFlowLog is enabled for LogGroupName: $FL" "$regx" "$vpcx"
        done
      else
        textFail "$regx: VPC $vpcx VPCFlowLog is disabled" "$regx" "$vpcx"
      fi
    done
  done
}